|Publication number||US2977170 A|
|Publication date||Mar 28, 1961|
|Filing date||Apr 8, 1957|
|Priority date||Apr 8, 1957|
|Publication number||US 2977170 A, US 2977170A, US-A-2977170, US2977170 A, US2977170A|
|Inventors||Hochman Julius C|
|Original Assignee||Hochman Julius C|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (5), Referenced by (3), Classifications (9)|
|External Links: USPTO, USPTO Assignment, Espacenet|
March 28, 1961 J. c. HOCHMAN 2,977,
LID-OPERATED ACTUATOR MECHANISM FOR CONTROLLING THE LIFT AND RETURN OF DROP-HEAD MACHINES AND MACHINES INCORPORATING THE SAME 5 Sheets-Sheet 1 Filed April 8, 1957 INVENTOR Julius djyockman g .2 f ATTORNEYS March 28, 1961 J. c. HOCHMAN 2,977,170
LID-OPERATED ACTUATOR MECHANISM FOR CONTROLLING THE.
LIFT AND RETURN OF DROP-HEAD MACHINES AND MACHINES INCORPORATING THE SAME Filed April 8, 1957 5 Sheets-Sheet 2 INVENTOR Julzusafiockman ATTORNEYS March 28, 1961 J. c. HOCHMAN 2,977,170
LID-OPERATED ACTUATOR MECHANISM FOR CONTROLLING THE LIFT AND RETURN OF DROP-HEAD MACHINES AND MACHINES INCORPORATING THE SAME Filed April 8, 1957 5 Sheets-Sheet 5 INVENTOR Jalzzzsaflockmam BY ofla/n/ JW- W ATTORNEYS M r 1961 J. c. HOCHMAN LID-OPERATED ACTUATOR MECHANISM FOR CONTROLLING THE LIFT AND RETURN OF DROP-HEAD MACHINES AND MACHINES INCORPORATING THE SAME 5 Sheets-Sheet 4 Filed April 8, 1957 INVENTOR JzzZz/as afiocizmarz/ mafw ATTORNEYS March 28, 1961 J. c. HOCHMAN 2,977, 7
LID-OPERATED ACTUATOR MECHANISM FOR CONTROLLING THE LIFT AND RETURN OF DROP-HEAD MACHINES AND MACHINES INCORPORATING THE SAME Filed April 8, 1957 5 Sheets-Sheet 5 INVENTOR Jalzas afiockman ATTORNEYS Unite Julius C. Hochman, 891 Park Ave, New York, NY.
Filed Apr. s,19s7, Set. No. 651,283
as Claims. c1. 312-26) The present invention is concerned with cabinets for drop head machines and while in its more general field of use it is applicable to typewriting and other machines,
it has particular utility in a sewing machine cabinet in which it is shown embodied.
The invention is more particularly concerned with machines of the above type in which a displaceable lid, generally a hinged lid for the cabinet, serves as the handle through which the lifting and return movement of the drop-head machine is automatically controlled, without the need for any other manipulationof any character whatsoever.
The invention relates not only to the machine assembly for its intended purpose, but to a simple mechanical unit to be affixed to the substantially conventional machine cabinet and by which the lifting and return of the drophead machine may be effected in the simple opening and closing movement of the lid.
An object of the invention is to provide a lid-operated mechanism for a drop-head machine of the above type such as a sewing machine, which is devoid of electric, spring motor or other auxiliary power drive, and devoid of dash pots, or gearing of any character whatsoever and which yet effects the desired lifting and dropping movement of the machine head in thoroughly reliable manner by the mere movement of the lid of the cabinet without material lifting effort on the part of the user, beyond f it that required to move the lid itself between closed and open positions.
It is among other objects to provide a drop head cabinet mounted machine such as a home sewing machine equipped with a lid movably (generally hingedly mounted to one end of the cabinet top), which, through a simple self-contained mechanism inconspicuously mounted within the cabinet, serves to automatically raise the sewing machine head, pivoted to the cabinet top, from dropped or dependent to raised or operative position, and which may do so without the need for a separate manual operation of raising or lowering the hinged front cover flap in order to elevate the machine, but which also has. means automatically to raise and tilt that front flap to and beyond operative position in order to permit the rise of the sewing machine head, the return of the front cover flap to horizontal position and thereupon the return of the sewing machine head to rest at the forward edge of its base upon the front cover flap, all in correctly timed sequence, without any likelihood or possibility of binding,
clashing or jamming, and to perform automatically subperform the sequence of operations previously set forth,
2 all by the simple opening and closing of the hinged lid of the machine.
Another object is to provide mechanism of the above type which may conveniently utilize, but is by no means limited to the utilization of substantially the booster construction made the subject of my previous U.S. Letters Patent No. 2,711,940, granted June 28, 1955.
Another object is to provide a mechanism of the type noted, which precludes the lifting or return of the drop head machine by manipulation of the head itself, but admits of such operation only by the opening and closing of the lid and is thus substantially proof against derangement by an impulsive user.
Another object is to provide a mechanism of such efiiciency and free operation, that it may be easily and conveniently operated, to .open a closed cabinet type machine to operative condition, or to shut an open cabinet type machine to closed condition, by a person seated before the machine inoperating position, the only manipulation required being the free swinging of the machine lid.
Another object is to provide mechanism of the above type which may be incorporated in a conventional drop type cabinet, with the mechanism so disposed within the cabinet as to leave the central well area completely free for. receiving the drop head, and without any of the mechanism visible from the exterior of the cabinet.
Another object is to provide a mechanism of the above type which admits of simple disconnection of the operative connection to the drop-head machine, so that when the machine is to be removed from the cabinet for adjustment, repair or replacement, the closing and opening of the lid may be effected without strain or interference from the mechanism, now unrestrained by the weight of the sewing machine head or the like.
Features of the invention are the substantially self-contained mechanism unit which comprises an actuating lever, desirably a bar, pivotally aflixed in the lid near the outer hinged end thereof, and extending through the top of the cabinet to the mechanism to be operated therefrom, .which latter mechanism extends transversely of the cabinet or at right angles to the actuating lever, the thrust being transmitted at such angle by the trunnions of a suitable sliding rotatable crosshead connection to an actuating plate structure pivoted to a main bracket, desirably suitable linkage to a lifting lever pivoted to the main bracket, which lifting lever engages the lower face of the machine head and serves to control the lifting and return movement of such head.
Another feature of the invention is the correct timing relationship in the movement of the lid and machine head to assure retarding of the lifting of the machine head at the beginning of the opening movement of the lid and to accelerate that lifting movement thereafter, in order to bring the machine head to the desired upwardly and backwardly tilted limiting position afterthe lid has been moved out of the range of travel of the machine head. To this end the actuating plate structure may include, in addition to the actuating plate proper, a driven plate which is cam driven therefrom and which in turn actuates the lifting lever, the cam connection being such as to effect the retarded initial movement and the accelerated final movement of the lifting lever in raising the machine head. Of course, a similar accelerating and retarding action and like clearance occurs in the return or closing movement of the lid.
Another feature is the means for effecting the correctly.
timed lifting of the hinged front cover flap of the cabinet to afford clearance for the automatic lifting of the machine head tobackwardly tilted position beyond its position of rest in the opening movement of the lid. That lifting is effected by an operating or connecting strip extending forward from the main bracket along a carrier bar which pivotally mounts a flap-lifting finger at its outer end, said finger also having a pivot connection to the connecting strip movable through an arcuate slot in the carrier bar, during the lifting action effected by a sliding movement of the strip. That sliding movement is effected by a cam on one of the plates, desirably the actuating plate which engages a roller near the inner end of the strip. Desirably the flap is automatically returned to closed position after displacement by the cam action, following the extreme backward tilted raising movement of the machine head, by means of a coil spring connected to the flap and the cabinet and stressed in' the lifting of the flap.
In the accompanying drawings in which are shown one or more of various possible embodiments of the several features of the invention,
Fig. l is a view in longitudinal cross section of the cabinet in closed position, showing the contained mechanism in side elevation viewed from the left hand side of the machine,
Fig. 2 is a view similar to Fig. l, viewed from the right hand side of the machine,
Fig. 3 is a view similar to Fig. 2, showing the machine at one stage of the lifting operation with the hinged front cover flap partly tilted upwardly,
Fig. 4 is a view similar to Fig. 3, showing successive stages of operation, in which the machine head protrudes above the top of the cabinet with the hinged cover flap raised to the limit.
Fig. 5 is a view similar to Fig. 4, showing the mechanism in substantially the extreme upwardly tilted position of the head with the front cover flap dropping downward and showing in dotted and dash lines the machine head base resting at its forward edge upon the front cover flap in its operative or horizontal position,
Fig. 6 is a view in longitudinal cross section, taken on line 6-6 of Fig. 1,
Fig. 7 is a view in longitudinal cross section, taken on line 77 of Fig. 1,
Fig. 8 is a perspective view of the bracket element that supports the operating and driven plates, and the carrier bar,
Fig. 9 is a perspective view of the actuating plate, and
Fig. 10 is a perspective view of the driven plate.
Referring now to the accompanying drawings, there is shown the outline of a generally conventional cabinet such as a sewing machine cabinet having a front wall 10, a rear wall 11, and a top platform 12 with a large generally rectangular central opening 13 therein, through which the heavy sewing machine head H is raised from its pendent position shown in Figs. 1 and 2 to the elevated position shown in Figs. 4 and 5 and lowered from the latter to the former. The conventional sewing machine cabinet top 12 also has the usual front support flap 14 which may be hinged as at 15 to the platform or top 12 to move between horizontal or support position shown in dot and dash lines in Fig. 5 and upward, raised or clearing position best shown in Fig. 4.
The conventional cabinet also has a lid 16 which in closed or idle position of the machine, covers the top 12 as shown in Figs. 1 and 2, and which in open or operating position, extends outward from one end of the cabinet, illustratively to the left of the cabinet top, as shown in dot and dash lines in Fig. 7. Desirably the lid is hinged as at 17 at its edge to the left edge of the machine platform or top 12.
The mechanism for moving the machine head automatically in the opening movement of the lid, and preferably also for automatically moving the flap 14 in correctly timed relation for clearance of the machine head in raising the same to its extreme upward backwardly tilted position and then returning the flap to horizontal position preparatory to return of the machine head to rest at the forward edge of its base upon the edge of the flap, is automatically controlled in timed relation, by the simple movement of the lid to open position, and substantially reverse sequence of operations is automatically effected in the closing movement of the lid.
The base B of the machine head H is hingedly mounted in conventional manner at its rear edge to the top platform 12 near the front of the rear wall of the cabinet, as at 18.
The actuating mechanism attached to the machine cabinet (which cabinet as thus far described is substantially conventional), will now be set forth.
The actuating device or mechanism for effecting displacement of the machine head and preferably also to effect displacement of the associated movable parts of the conventional cabinet by the usual opening and closing movement of the lid, preferably comprises a main bracket U, which desirably consists essentially of a bracket plate 24 desirably having a flange 21 at right angles thereto at its upper edge, by which it may be attached as by screws (not shown), to the under face of the cabinet top 12, and also has a similar flange 22 at its lower end. That main bracket is preferably near the left end of the rear wall 11 of the cabinet and the bracket plate 20 extends preferably parallel to the end edge of the platform or the hinged edge of the lid 16. The main bracket U is desirably stiffened by an angle bar 88 along its rear edge which angle bar is fastened as by screws 88' to the rear wall 11 of the cabinet.
The actuating transmission between the hinged lid (extending usually from the left side edge of the cabinet) and the hinged base B of the drop machine (which in the embodiment shown is a sewing machine and extends in dropped position downward from the rear portion of the sewing machine platform or top 12), thus transmits the" lifting effort from lateral or longitudinal movement of the lid in opening and closing the cabinet to forward and backward or movement transversely of the cabinet in lifting or dropping the drop-head machine.
To this end (referring to Fig. 7), an actuating lever 25 is desirably hinged by a suitable pin 26 across a longitudinal kerf or groove 27 near the rear edge of the lid 16 and of depth materially less than the thickness of the lid, so that the exposed face of the closed lid remains intact.
Lever 25 may be and preferably is of resilient flat stock and extends through a longitudinal slot 28 through the top wall or platform 12 of the cabinet to the mechanism actuated thereby, and presently to be described. That mechanism is mounted upon the main bracket U, and extends generally forward from the bracket for coaction with the booster acting upon the drop-head machine base to eifect the lifting action in opening the lid and the release or drop action in closing the lid.
In a preferred embodiment shown, the mechanism carried by the main bracket U, is connected to the inner end of said lever in a manner to transmit the effort exerted from the lid upon the actuating lever in plane at right angles to that in which the actuating lever is moved.
In a preferred embodiment shown, this right angle transmission may be accomplished by a sliding rotating crosshead connection between the actuating lever 25 and movable plate means, which means includes an actuating plate 30 that may-be pivoted at 19 in substantially faceto-face relation against the bracket structure U. In the specific embodiment shown, the main bracket U has a bracket plate element 23 which may be unitary therewith, but is shown as a plate with an angle bar flange 24 afiixed by rivets 24' to the main bracket U. If desired, the bracket 23 may be applied to the cabinet itself, independently of the main bracket U.
For the right angular tnansmission set forth, the
actuating plate 30 is preferably formed with an angle plate conformation, whichconformation has a leftwardly extending web 31 at right angles to the bracket plate 20, the outer edge of which has an upstanding flange 32 parallel to the bracket plate. Referring to Figs. 7 and 9,
a transverse pin 33 is afiixed at one end in the upstanding flange 32 of the actuating plate and at its other end in an extension lug 34 extending parallel to the plate generally upward along the bracket face 20 from the lower end of a rearwardly extending lug 35 near one end of the web 31 of the angle plate conformation.
The inner end of the actuating lever 25 is formed as a clevis 36, which straddles and is hingedly mounted by trunnions 37 to a sliding and rotatable crosshead 38 about the transverse pin 33.
The actuating lever 25 carries a roller 40 pivotally affixed thereto near the root of the clevis and extending forward therefrom for rolling engagement with the under face of the upper bracket flange 21 when the lid :is in open position, and for rolling along said flange for a portion of the opening and closing movements of the lid and the hinging movement of the actuating lever 25 therewith to move the crosshead 38 to the left toward the lid and toward the flange 32 of the angle plate conformation of the actuating plate. In the closing movement of the lid, thrust is transmitted through the actuating lever 25 and the crosshead slides toward the extension lug 34 rising from the Web 31, and as the lid approaches substantially the vertical, the heel of the forward arm of the clevis abuts against extension lug 34, arresting the sliding movement of the crosshead, and the actuating lever 25 then exerts a substantiallydownward thrust in the further closing of the lid to effect a rotatory movement of the actuating plate 30 about its pivot 19. The domed head (not shown) of the cross piece 33, and a pair of small domed projections 89 in lug 34, reduce the friction of the actuating plate 30 against the main bracket plate 20.
The actuating plate 30 in its rotary movement about its pivot 19 or pivot hole 19, operates linkage (herewith described), also carried by the main bracket U and. extending preferably transversely or rearwardly from the front of the cabinet substantially parallel to the actuating plate 30.
By suitable linkage hereinafter described, a lifting lever '45 which may desirably be V-shaped in form, is moved about its pivot 46 which extends through the main bracket U near the free end of theupper partof its bracket plate 20. This lever 45 has a roller 47 arranged to ride along the drop-head base B-near its free edge to lift the head from its lowermost or "dropped position, shown in Fig. 2, to its uppermost position in finally placing the machine head in operative position of use, as shown in dot and dash lines in Figs. 4 and 5.
For facility of lifting, a spring 48 may be coiled about pin 46 held near the upper flange 21 ofthe bracket U, to react at one end 48' against the horizontal part of upper flange 21 of bracket U, with its other end 48 hooked about pin 49 protruding outward from the side of lifting lever 45 through a toggle link 50 pivoted at 51 to a toggle lever 52 which is pivoted at its lower end about a pin 53 which extends transversely across the lower channel 22 of the main bracket U, that is, between the bracket 20 and the ledge 22' which rises from the outer edge of the lower flange 22 of the bracket.v A spring 53 coiled about pin 53" reacts at one end 53' against fiange 22 and at the other 53 against toggle lever 52.
To prevent the machine head from striking the under surface of the lid in the opening and closing motions, means is provided toretard the rise of the machine head during the first portion of the opening operation, and to accelerate it during the latter portion of its motion. Conversely, in the closing operation, the motion of the head is accelerated during the first. portion of the swinging of the lid, and retarded during the latter ,portion.
To accomplish this objective, a driven plate 60 may be employed, desirably in t'ace-to-face engagement with the actuating plate 30. That driven plate 60 in a preferred embodiment shown, is interposed between the actuating plate 30 'andthe bracket plate member 23, the drivenplate illustratively riding in face-to-face engagement with the bracket plate 23, and the actuating plate 30 in face-to-face engagement with said driven plate 60.
The driven plate 60 is desirably pivoted to the main bracket U, and in the embodiment shown, to the bracket plate 23 thereof,'by means of a pivot pin 61 spaced laterally, as shown, from the pivot 19 of the actuating plate 30.
The driving connection between the actuating plate 30 and the driven plate 60 is desirably by a roller and camslotconnection. ,This connection maylinvolve a cam slot 62. in the driven plate, the outer portion of the slot of which is desirably substantially concentric with the pivot axis 19 of the operating plate, while the left-' ward portion of the length of the cam slot 62, as shown in Fig. 10, is in a more nearly radial relation to effect accelerated movement of the driven plate 60 relative to the motion of the actuating plate 30 for the desired purpose.
The drive from the actuating to the drivenplate is desirably eifected by a roller 63, riding in the cam slot 62 and mounted atthe lower end of a pin 64 extending through a bearing at the lower part of the actuating plate 36 near the end that carries roller 63 and extending near its other end through flange 32. A coil spring 65 about the pin 64 urges the roller 63 into the cam slot 62. The initially retarded lifting of the drop-head and the-finally accelerated movement in, that stroke (and conversely as above set forth), is brought to pass by driving the lifting lever, not directly from thev actuating plate,,but through the cam of the driven plate 60. This drive may be effected by a short transmission link or vpitrnan 66 pivoted at its forward end to the lug 67 of the drivenplate 60 which approaches the main bracket 'U by its offset root, said link being connected at its other end to the lifting lever 45, desirably at the fixed pivot pin-46 for the toggle link 50.
-, To afford clearance in the movement of the actuating plate 30 and the driven plate 60 relative to each other, pivotpin 61 (which passes, through a bearing, aperture 61 of said driven plate), rides in an arcuate slot 67 coaxial with the mounting pin 19 (which passes through I aperture '19 of, said, actuating plate).
the actuating plate 30 rides in an arcuate slot 68 coaxial with the axis 6-1, 61' of the driven plate 60. I
While the transmission between the actuating plate and the drop machine base has been described as such, it will be understood that the present invention may incorporate substantially, the booster construction of my .prior Patent 2,711,940, granted June 28, 1955, entitled ,Drop Head Machine and Booster, substantially as ,shown in the drawings. Thus the main bracket U, the lifting lever 45, the toggle lever 50, the toggle link 52 and the associated springs '48 and 53 may be substantially those of that patent, so that the booster construction of said prior patent, instead of being brought into effective operation by manually lifting or lowering the drop-head machine after the cabinet lid has first been opened, is automatically actuated from the cabinet lid 16 in its opening or closing movements, the various lifting and lowering forces being applied through the lid by the transmission described, by way of the short link 66 pivoted to the fixed pin in the booster lifting lever 45.
All of the advantages of the booster mechanism made the subject of my prior Patent 2,711,940 are maintained in the present application, with the additional utility,
however, that the mere manual movement of the machine Pivot pin 19 of to the booster effective for raising the drop-head to operative position and the closing movement of the lid effects the required initial raising and then the lowering or dropping of the drop-head machine H into the cabinet without sacrifice of any of the advantages set forth in my said prior patent.
While in the disclosure of my prior Patent 2,711,940, it was necessary to raise the flap 14 of the cabinet top manually, for clearance in raising or lowering the ma: chine head, and then to lower the flap to seat the forward edge of the machine base upon theflap from its extended tilted back position, the present invention affords means for automatically operating the cover flap 14 in the opening and closing movements of the lid with no further attention on the part of the operator.
To this end, the invention may include means controlled from the actuating plate 30 for lifting the cover flap in correctly timed relation to the lifting of the machine head and for then releasing said flap, so that the machine head may then be returned from its extreme back tilted position to become seated in the final portion of the lid opening movement at the forward edge of its base upon the fiap M, such flap lifting mechanism also to operate to raise and lower the flap at the correct time automatically in the closing movement of the lid to permit dropping or depressing movement of the head H.
To this end, means is provided, generally shown at F (controlled from the actuating plate 30), which extends forward from the actuating plate 30 and generally parallel to the bracket plate and has a lifting finger 70 to apply the lifting thrust to the under side of the hinged front flap 14.
A preferred embodiment of the flap-operating mechanism is shown in the drawings,. It includes a carrier bar 71, which'at its rear end may desirably be mounted upon the two pivot pins 19 and 61, but need not be secured with absolute immovability thereabout. That carrier bar 71 serves as a cover plate for the bracket to maintain the actuating plate and the driven plate 60 in position on bracket plate 23. Near the forward end of that carrier bar, there is pivotally mounted about pin 72, the shank 70' of the flap-lifting finger 70, that finger desirably being curved at its outer or flap-engaging end, as shown. The carrier bar 71 desirably has a stifiening flange 71' turned inward from its upper edge, and extending to a terminal bracket 71 at the forward e1;- tremity of the mounting bar, which bracket serves for affixing that end to the under face of the top wall or platform 12 of the cabinet.
Slidably mounted on the carrier bar 71 is a flap fingeroperating thrust strip '73 which is guided between guide fingers 74 struck out from the carrier bar 71 and extending over the respective edges of the thrust strip 73. Near its free or forward end, the thrust strip 73 is desirably connected to the flap-lifting finger 7% by a pivot pin 75 aflixed at one end to the shank 70' of the flap-lifting finger 7i and movable in an arcuate slot 76 in the carrier bar, concentric with finger mounting pivot pin 72.
The lifting thrust is transmitted to flap 14 in timed relation by means of arroller 77, affixed to the thrust strip and operated in timed relation by a cam edge 78 on the actuating plate 30 and slidable in a slot 79 in the carrier bar 71.
With the machine in open position, it is possible manually to tilt the machine head above the cabinet top and manually to raise the front flap 14. With the front flap open, an uninformed or impulsive user might attempt manually to lower the machine head down into the cabinet in the same manner as is required where a booster such as that of my prior patent, not actuated from the lid of the cabinet, is used. Were the equipment devoid of means to prevent such manual lowering of the machine head with the lid open, the short connecting link or pitman 66 which passes outward beyond dead center position when the machine head is lowered to horizontal or 8 operative position, would continue in this outward'direu tion and would tend to force the driven plate 60 downward beyond its normal position and thereby lock or strain the actuator mechanism. Such mismanipulation is prevented by forming the toggle link 5% with a projecting shoulder50, against which a side edge of the link 66 would abut in such attempted downward forcing of the machine head, thus precluding the actuator mechanism from being forced into a locked or jammed position. Thus the machine head can be lowered only by the pivoting movement of the cabinet lid 16 and the incidental operation of the actuator mechanism therefrom.
While the operation may be understood from the foregoing description, it will now be set forth for ease of understanding.
As the lid 16 of the cabinet is opened, the hinged upper end 26 of the actuating lever 25 moves with the lid through 180 degrees. In this movement, lever 25 is pulled upward and through the slot 28 in the platform 12, turning therewith through the sliding rotating crosshead connection 36, 37, 38, the actuating plate 30 which moves about its pivot 19. In this movement, as the actuating lever 25 approaches its final nearly horizontal position in the fully open position of the lid 16, the roller 40 on said lever 25 rides along the under surface of the flange 21 on the bracket U and the crosshead moves to the right on its pin 33.
In the first portion of the movement of the actuating plate 30, there is little or no movement of the driven plate 66 so that there will be no premature lift of the machine head to strike the lid. As the roller 63 mounted on the actuating plate, passes the sharp bend in the cam slot '62 of the driven plate 66., that plate accelerates in its rotation about its pivot pin 61 relative to the actuating plate 30 and through the link 66, it pivots the lifting lever 45 upward as far as it will go, thereby moving the drophead -H upward to and beyond operative position to tilt it to extreme back position, as shownin Fig. 5. The highest point of the machine head is reached when the driven plate 60 and the link or pitman 66 reach a straight line or dead center position.
While this is occurring, the cam edge 78 of the actuat- I ing plate 30 forces the roller 77 on the thrust strip 73 forwardly to cause its pin 75 to shift the lifting finger '70 about its pivot 72, thereby engaging the under face or" the hinged flap 14 and tilting it upward to raised position. By the time the machine head has reached its extreme upper position, the thrust strip roller 77 will have been cleared by its operating cam 78 and the coil spring s that has been stretched in this lifting motion will urge the cover flap 14 downward to horizontal position preparatory to release of the backwardly tilted head. In the final portion of the lid opening movement, the lifting lever 45 will be drawn downward as driven plate 69 and link or pitman 66 in'the continuance of their forward motion, pass their straight line or dead center position, so that the machine head will come to rest with the forward edge of its base upon the horizontal front flap l4 and the machine is ready for use.
In this lifting operation, as set forth in my prior Patent 2,711,940, in a desirable embodiment of the invention, thefsprings 48 and 53 assist in the lifting movement and thus do not necessitate the need for exerting much more lifting force to the lid 16 in moving the same from closed to open position than is required by the weight of the lid itself.
In the open position of the lid, the actuating lever 25 rests, near its middle, upon the metal fulcrum bracket 87 afiixed preferably to the side of the cabinet, under the slot 28 of the platform 12, with the roller it} and the inner end of actuating lever 25 pressing upward against the undersurface of main bracket 21, the lever 25 thus serving as a brace for the lid when in open position and relieving the lid hinges of excmsive strain. In the open or sewing position, the weight of the lid 16 partially counteracts the upward or lifting power of the. lifting springs 48 and 53 and contributes to a more firm and vibrationless rest for the machine head on the cabinet top.
To close the machine, all that is necessary is to move the lid 16 from open to closed position. As the lid 16 is lifted, the lower end of the actuating lever 25 is drawn to the left, the roller 49 rolls along the bracket portion 21 and the crosshead 38 moves toward the left portion of its supporting pin 33. The actuating lever inclines downward, causing the clevis and crosshead to move downward, and immediately commence the downward pivotal movement of the actuating plate 30. As the actuating lever 25 in its continued tilting movement, progresses with closing movement of the lid, the crosshead then moves along the slide rod to the right until the edge of clevis 36 strikes the lug 34 of the actuating plate 36. In the continued movement of the lid, the clevis 36 still in contact with the lug 34 of the actuating plate, pivots that plate about its pivot pin 19 downward sharply, until as the lid approaches completely closed position, the actuating lever. 25 is nearly vertical. In the downward movement of the actuating plate 30, the driven plate 60 is accelerated to maximum speed at the beginning relative to the actuating plate 36 and the lifting lever 4-5 is rapidly lifted, the driven plate 60 and linkor pitman 66 reaching dead center position to tilt the machine head H upward and backward and then as the rapid movement proceeds, the driven plate '66 and link 66 draw the lifting lever 45 downward in time to prevent the machine head being struck by the closing lid, the base of the drop-head H engaging on roller 45 of the lifting lever, during all these movements.
Occasionally the service department of the sewing machine agency is required for service or repair of the sewing machine, for which purposes the sewing machine head may be removed by such service man for taking to the shop. With the weight of the sewing machine head no longer present to restrain the springs 43 and 52, it becomes important to disengage the lid actuated linkage from the lifting lever 45 in order to guard the hinges "of the lid from objectionable stress, aswhen the lid is lowered on the empty cabinet. This is important to avoid disfiguring the living room of the user by the necessity for keeping the lid open while the sewing machine head is absent. To attain the objective, the driving connection from the lid to the lifting lever must be interrupted and the lifting lever mustbe locked in partially downward position.
For this purpose, the lifting lever 45 may be hooked down in partially depressed position by the hook end 85 of the restraining hook 83 in the opening 86 of the lifting lever 45. vThereupon the cam roller 63 which constitutes the driving connection between the actuating plate 30 and the driven plate 60 and which normally rides in the cam slot 62 is retracted.
To render possible these operations, it is first necessary toraise the lid 14 to substantially a vertical position while simultaneously depressing the lifting lever 45 manually sufficiently to permit introducing the hooked end 85 of wire link 83 into the hole 86 of the lifting lever to lock the same into position below the platform top. I
The raising of the lid' just set forth, results in a rearward or inward motion of the linkage comprising driven plate 60 and link 66 past their dead center position, similar to their motion in closing the'cabinet. The manual depression of the lifting lever 45 simultaneously with the closing movement of the lid, prevents objectionable straining of the lid hinges in the absence of the machine head, pending the engagement of the wire hook 85.
Thereupon the driving roller 63 is disengaged from cam slot 62 in driven plate 60 to interrupt the driving connection from the lid to the booster linkage. For this purpose a handle rod 80 is preferably affixed to pin 64 lodged in notch 82' by spring 65 which normally urges 10 the driving roller 63 to driving position." Notch 82 is located between two bent up lugs 82 onledge 32 of the actuating plate 30. One of the lugs 82 has a rest notch 81 for retaining the pin 64 in withdrawn or disconnect position.
After the lifting lever has thus been hooked and the retractable cam roller has thus been withdrawn from the cam slot 62, the machine head may be removed from the cabinet or, as is generallypreferred, it may so be re moved by the mechanic before the hooking of the lifting lever and the retraction of the cam roller.
The means to lock the lifting lever, as above described, is desirably substantially that shown on Sheet 3 of the prior Hochman patent above referred to. This means comprises the wire link 83 above alluded to which is pivoted on lug 84 on the main bracket U, the hooked end 35 of which link, when raised, Will register with and may be introduced in the hole 86 in the lifting lever 4-5.
Thus the swinging movement of the lid 16 will transmit no impulse to the driven plate 60 and therefore will not release the lifting lever 45 from its downwardly locked position. The lid may be freely swung between open and closed position without possibility of strain or injury or any effect upon the disengaged position in which the actuating linkage and booster has been left by the mechanic.
Upon reinstallation of the machine head H into the cabinet, the driven plate actuating roller 63 is readily restored to operative position by lifting the handle 86 out of notch 81 and restoring it to its normal position in which the coil spring 65 will urge the roller 63 back into its cam slot 62 in driven plate 60. At such time the wire hook '83 also is released and the machine has been restored to operative position.
It will thus be seen that the present invention affords a relatively compact and inexpensive construction made of a few stampings of sheet steel, a few small screw machine parts, and coil springs, readily assembled, without the need for close tolerances, and which is substantially proof against derangement.
All that is needed for moving the machine from dropped to operative position is to open the lid. All that is needed to restore it to dropped position is to close the lid. All of the operations are automatically performed in predetermined correct timed sequence, as set forth, without striking of the machine head or other part against the lid.
While in the construction shown in the drawings, as above described, the booster of my prior patent is a component element of the sewing machine lid actuated mechanism (with the minor structural modifications pre viously described), for positioning the sewing machine head as described, and the bracket U of said booster serves as the primary mounting structure for the entire operating mechanism, it will of course be understood that some or all those elements that perform the function of the booster, as in my earlier Patent No. 2,711,940, could be incorporated in the actuator mechanismwithout constituting substantially a sub-assembly which corresponds to the booster of said prior patent.
It will also be understood that a separate actuator unit comprising a bracket plate 23 andassociated elements can be made, as a completely independent mechanism, itself affixed to the cabinet, with only an actuating element (such as link 66), serving operatively to connect the actuator unit to a booster unit. As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope of the claims, it is intended that all matter contained in the above description, or shown in the accompanying drawings, shall be interpreted as illustrative andnot in a limiting sense.
Having thus described my invention, what I claim 11 as new and desire'to secure by Letters Patent of the United States is:
1. In a drop-head machine of the type comprising a cabinet having a top, a machine head having a base to be positioned upon said top for use and displaceable from said position of use, to drop to idle position wholly below said position of use, such cabinet having a lid hinged to one end thereof and movable about said hinge through a straight angle to expose the top of the cabinet, and a connecting linkage between said lid and the base of the machine head for elevating and maintaining the machine head in position of use by movement of the lid to extended position and for returning the machine to dropped position within the cabinet by the return of the lid to closed position; the combination in which the machine head rests directly upon the cabinet top for use and in which the linkage includes an actuating lever extending across the thickness of the cabinet top and pivoted at one end to the lid, a bracket aflixed to the cabinet, and transmission linkage mounted on said bracket and extending in such cabinet generally at right angles to said actuating lever, said linkage including a lifting lever pivoted to said bracket for engagement with the base of the drop-head machine, said linkage including a rigid driving connection from the actuating lever carried by the bracket and serving to actuate the linkage in a plane generally at right angles to that of the actuating lever.
2. The combination recited in claim 1 in which means are provided for engaging and disengaging the linkage,
whereby the opening and closing movements of the lid will be transmitted to the lifting lever when the linkage is engaged and will not be transmitted to the lifting lever when the linkage is disengaged.
3. The combination recited in claim 2, including means for maintaining the end of the lifting lever below the cabinet top when the linkage is disengaged.
4. The combination recited in claim 1 in which the lifting lever has associated linkage and spring means to constitute in coaction a booster for assisting the rise of the drop-head machine and for cushioning its drop and maintaining the drop-head machine in the dropped position against undesired lift thereof, and in which the transmission linkage includes means intervening between the actuating lever and the booster for actuating the latter.
5. The combination recited in claim 1 in which the transmission linkage includes a plate having a horizontal pivot mount substantially at right angles to the lid hinge, said plate having a yoke connection to the inner end of the actuating lever, and a link connected between said plate and said booster unit for transmitting thrust to the latter.
6. The combination recited in claim 1 in which the top of the bracket is aflixed to the undersurface of the cabinet top, and in which the actuating lever extends downward through a slot in the cabinet top, a roller being mounted on one side of said actuating lever near its inner end, said roller and inner end of said lever passing underneath said bracket top, and in which a metallic fulcrum member is fixed to the top of the side panel of the cabinet and extends across the width of said slot, the middle portion of the actuating lever resting on the fulcrum member, with said roller and said inner end pressing upward against said bracket when the lid is in open position, whereby the actuating lever forms a rigid lid brace to prevent inadvertent forcing below the horizontal.
7. In a drop-head machine of the type comprising a cabinet having a top, a lid movably mounted between position of superposition to close the top and open position outward from the top, a machine head having a base to be positioned upon said top for use, hinged thereto and displaceable from such position of use to dropped idle position wholly below said position of use, the cabinet top having a hinge flap for supporting the forward edge of the drop-head machine supporting base for use, and
displaceable to open position for affording room to permit dropping of the machine head to inoperative position; the combination therewith of actuating linkage intervening between the lid and the drop-head machine, said linkage including a lifting lever for engaging and lifting the drop-head machine base from idle to backwardly tilted uppermost position, and also including a thrust strap for raising and-then releasing the flap to horizontal position, and resting the edge of the machine base upon the flap, and in moving the lid to closed position, first lifting the machine base above position of use, lifting the flap, releasing the machine head to dropped position and releasing the flap to normal position, all of said operations in sequence, free from interference or clashing.
8. The combination recited in claim 7 in which the lid has a pivot mount at one end of the cabinet and is movable through a straight angle between closed and open position; in which the actuating linkage includes an actuating lever movable in a plane at right angles to the pivot mount at one end of the lid, a bracket aflixed to the cabinet, extending generally parallel to the pivot mount, an actuating plate pivoted to said bracket and substantially parallel thereto, a crosshead connection between the inner end of said actuating lever and said actuating plate for movement of the latter from the former, a lifting lever pivoted to said bracket for engagement with the base of the drop-head machine, means controlled from said actuating plate to actuate said lifting lever, and means controlled from said actuating plate for actuating said flap-lifting means, in timed relation, preparatory to raising and to lowering the machine head.
9. The combination recited in claim 8 in which the top of the bracket is affixed to the undersurface of the cabinet top, and in which the actuating lever extends downward through a slot in the cabinet top, a roller being mounted on one side of said actuating lever near its inner end, said roller and inner end of said lever passing underneath said bracket top, and in which a metallic fulcrum member fixed to the top of the side panel of the cabinet extends across the width of said slot, the middle portion of the actuating lever resting on the fulcrum member, with said roller and said inner end pressing upward against said bracket when the lid is in open position, whereby the actuating lever forms a rigid lid brace to prevent inadvertent forcing below the horizontal.
10. The combination recited in claim 8 in which means are provided for engaging and disengaging the actuating linkage, whereby the opening and closing movements of the lid will be transmitted to the lifting lever when the linkage is engaged and will not be transmitted to the lifting lever when the linkage is disengaged.
11. The combination recited in claim 8, including means for maintaining the end of the lifting lever below the cabinet top when the connecting element is disengaged.
12. The combination recited in claim 8 in which a bracket is affixed to the cabinet, transmission linkage is mounted on said bracket, said transmission linkage including a plate pivoted to said bracket on a substantially horizontal axis, said actuating plate having a crosspin and said actuating lever having a crosshead equipped with trunnions at its inner end slidable on said cross-pin for pivotal movement of said actuating plate from said actuating lever, a driven plate in substantially face-toface relation with said actuating plate, a cam drive con nection from said actuating to said driven plate for retardation of the latter at one phase of its movement and acceleration at another phase thereof, a booster assembly for aiding the lift and restraining the drop of cabinet of the type equipped with a lid movable from closed position with the machine in dropped position, to extended position, in which the conventional base of themachine rests in operative elevated position directly on the cabinet top for use; said unit serving automatically to displace'the machine from dropped to operative position in opening the lid and from operative to dropped position in closing the lid; said unit comprising abracket adapted for mounting within the cabinet, actuating mechanism comprising an assemblage of stamped metal cams mounted on said bracket and linkage including a rigidly coacting with said actuating mechanism foroperation as set forth, respectively, by the manipulation of the lid to opening or closing position.
- 14. The'com-bination recited in claim 13 in which means are provided for connecting and disconnecting the assemblage, whereby the opening and closing movements of the lid will be transmitted to the lifting lever when the assemblage is connected and will not be transmitted to the lifting lever when the assemblage is disconnected.
15. The combination recited in claim 14, including means for maintaining the end of the lifting lever below the cabinet top when the connecting element is disconnected. Y
16. A unit for incorporation in a drop-head machine cabinet of the type equipped with a lidhinged to one lateral edge of the cabinet and limited for movement about the hinge through a straight angle between closed position and extended or open position of the lid; said unit comprising a bracket adapted for mounting within the cabinet, mechanism mounted on the bracket comprising sheet metal cams and links and including a lifting lever adapted for engagement with the base of the drophead machine to apply thereto a lifting thrust and to release the same by the mere movement of the lid, an actuating lever for applying the machine lifting and releasing impulse to the mechanism, means adapted to pivot the outer end of said lever to the hinged lid, said lever having a rigidly operative connection at its inner end to the mechanism for raising the machine to' operative position by the mere opening of the lid and for dropping the machine to depressed position by the mere closing of the lid. 17. In a dropped-head sewing machine cabinet of the type having a platform, a sewing machine head having a base extending lengthwise of said platform and hinged thereto, a lid hinged to one side edge of the platform and movable through a straight angle between closed and extended or open position, and mechanism for pivoting the machine head upward to operative position by the mere opening of the lid, and pivoting the machine head to depressed position by the mere closing of the lid; said mechanism comprising bracket means for installation within the cabinet, an assembly of sheet metal parts carried at one end by said bracket and extending generally indirection parallel to the end of the cabinet, said linkage including a lifting lever engaging the base of '14 18. The combination recited in claim 17 in which means are provided for engaging and disengaging an element normally connecting two of the moving parts, whereby the opening and closing movements of the lid will be transmitted to the lifting lever when the connecting element is engaged and will not be transmitted to the lifting lever when the connecting element is disengaged.
*19. The combination recited in claim 18, including means for maintaining the end of the lifting lever below the cabinet top when the connecting element is disengaged. 20. The combination recited in claim 17 in which the top of the bracket is afiixed to the undersurface of the cabinet top, and in which the actuating lever extends downward through a slot in the cabinet top, a roller being mounted on one side of said actuating lever near its inner end, said roller and inner end' of said lever passing underneath saidbracket top, and in which a metallic fulcrum member fixed to the top of the side panel of the cabinet fills the width of said slot, the middle portion of the actuating lever resting on the fulcrum member, with said roller and said inner end pressing upward against said bracket when the lid is in open position, whereby the actuating lever forms a rigid lid brace to prevent inadvertent forcing below the horizontal.
21. The combination recited in claim 17 in which the .machine cabinet is of the type provided with a hinged flap longitudinally thereof in its platform, adapted to be raised in lifting the machine head to extreme upper backward tilted position and adapted to be returned'to closed position for sustaining the forward edge of the machine base in operative position; the combination therewith of means incorporated in the mechanism for automatically lifting to extreme upper backward tilted position and releasing the said flap in timed relation in the mere opening and closing of the lid..
22. The combination recited in claim 21 in which said flap-operating mechanism comprises a thrust strip, asupport therefor, operating means for coaction with said thrust strip to move the same outwardly, and means actuated by said thrust strip in such outward-movement,
for raising the flap, and means for automatically return- ,ing thefiap to horizontal position.
.23. The combination recited in claim 22 in which the .means for returning the flap is a spring connected at lifting of a machine head from dropped to operative the machine head, and means for actuating the mechaposition and conversely, said unit comprising two levers, two springs connected to the respective levers, one of the springs being stressed to assist the lifting of such head and to oppose dropping the same, the second of the springs being arranged with respect to'such head to assist in the lifting operation and to become reversed in the direction of its thrust during the final part of the depression movement of the head to oppose the other spring and thereby assist in maintaining the head in depressed and idle position; the mechanism including a transmission from the actuating lever to the booster unit comprising driving plate means extending parallel to and pivotally mounted upon said bracket and operatively connected for rotation by the movement of the actuating lever in the opening and closing movement of the lid, and a connection between said driving plate means and said booster unit for actuating the latter from the former.
25. The combination recited in claim 24 in which a link pivoted near its opposite ends respectively to the driving plate means and to the lifting lever serves to transmit raising and lowering impulses, respectively, to the booster unit.
26. In a droppedhead sewing machine cabinet, actuating plate means, a bracket, a booster structure including linkage mounted on said bracket, which linkage includes alifting lever forengaging the base of the dropped head machine, and a pair of coil springs mounted on' said bracket, one of said springs being directly connected to said lifting lever, and linkage connecting the other of said springs to said lever; said elements being arranged for operating in timed relation for assisting each other during the lifting movement and opposing each other during the dropping movement, a link connected from said actuating plate means to said lifting lever for actuation of the booster means, an actuating lever for connection near one end to the movable lid of a drop-head machine, and having a crosshead near the other end, a cross-pin carried by the actuating plate means for mounting said cross-head, whereby thrust from the actuating lever is transmitted to shift the actuating plate means in a direction at right angles thereto for operation of the mechanism.
27. The combination recited in claim 26, which includes a conventional hinged cover flap that supports the front end of the machine base and means for automatically controlling the opening and closing of said flap.
28. The combination recited in claim 27 in which said means comprises a carrier member, a flap-lifting finger pivoted to said member, a thrust strip movably mounted on said member and pivoted at its forward end to said finger, said actuating plate structure having a cam conformation and a follower afiixed on said strip for operation from said cam conformation in timed relation to effect the lifting of the cover flap.
29. A mechanism of the character described comprising a bracket plate structure, an actuating plate pivoted to said bracket structure and parallel thereto, a driven plate pivoted to said bracket structure and substantially against said actuating plate, a cam driving connection for turning said driven plate from said actuating plate, a lifting lever pivoted to said bracket plate structure and serving to apply and relieve thrust for lifting or releasing a drop-head machine, booster linkage mounted on said bracket plate means and connected to said lifting lever, and a pivoted connecting link controlling the motion of the lifting lever and its associated booster linkage from the driven plate.
30. The combination recited in claim 29 in which the mechanism includes cover flap-control means, said means comprising a carrier, a flap-lifting finger pivotally mounted thereon, a thrust strip having a roller near the inner end thereof, one of said plates having a cam periphery coacting with said roller for operating the flaplifting finger in timed relation.
31. A mechanism of the character described, comprising a bracket plate structure adapted to be afiixed in the cabinet of a drop-head sewing machine, a driving plate and a driven plate pivoted in substantially superposed relation against the face of said bracket plate structure, a cam connection between said driving and said driven. plates for turning the latter in the turning movement of said driving plate, means adapted to be connected to the hinged lid of a sewing machine cabinet for turning the driving plate as an incident to the movement of the hinged lid, said mechanism including a lifting lever pivoted to said bracket plate structure, a link connected at one end to said driven plate and at the other to said lifting lever, and spring-actuated booster linkage carried by said bracket plate and connected to said lifting lever.
32. The combination recited in claim 31, in which a carrier extends forwardly from the bracket structure and a thrust strip is mounted thereon for movement longitudinally thereof, a cover flap-lifting finger is pivoted to said carrier, the end portion of said strip being pivotally affixed to said lifting finger for pivoting the same upward in the longitudinal movement of said strip, said strip having an operating roller near its inner end and a cam conformation on said actuating plate for shifting said strip in the course of rotation of said actuating plate, and an actuating lever connected at its inner, end to said actuating plate for movement of the latter in a plane at right angles to said actuating lever, said connection comprising a crosshead on the inner end of said actuating lever, and a cross-pin on said actuating plate for mounting said crosshead.
33. The combination recited in claim 31 in which the mechanism comprises a bracket frame plate having an upper and a lower flange thereon, pins intervening between the bracket and the respective flanges, a lifting lever pivoted on one of said pins, a toggle linkage having one arm pivoted on the other of said pins and the other arm pivoted to said lifting lever, springs about the respective pins connected for booster action in the operation of the lifting lever and an actuator for said boosteroperated lifting lever, said actuator comprising an actuating plate and a superposed driven plate pivoted in superposed relation to the bracket plate, said actuating plate having an angle beam formation at one side thereof, a pin across said angle beam formation, an actuating lever having a pivot means at its outer end for connection to the lid of the cabinet of a drop-head machine and having a yoke at its opposite end, a cross head at the inner end of said actuating lever and about said cross-pin, a roller on one side of said actuating lever near the yoke and adapted in the movement of said actuating lever to roll along the upper flange of said bracket, said actuating plate having a pivot mount substantially against said bracket means, a driven plate against said actuating plate and having a pivot mount with respect to said bracket laterally displaced from that of said actuating plate, each of said plates having an arcuate slot for accommodating thepivot movement of the adjacent plate, a roller and cam slot connection between the actuating plate and the driven plate for moving the latter at variable speed in the movement of the actuating plate at fixed speed, a link pivoted to the driven plate at one end and to the lifting lever at the other for actuating the latter from the driven plate, and means for automatically controlling the lift and return of a cover flap, said means comprising a substantially fixed carrier bar extending forward from the actuating plate, a cover flap-lifting finger pivoted to said carrier bar, a thrust strip mounted on said carrier bar and having a pivot connection at its free end to said operating finger and a roller on said thrust strip, said actuating plate having a cam conformation for coaetion with said roller to shift said strip to raise said flap-operating finger in the movement of said actuating plate;
34. The combination recited in claim 33 in which the cam drive between the actuating and the driven plate comprises a spring-urged roller, a slidable pin on the actuating plate mounting said roller and a cam slot in the driven plate accommodating said roller, and in which a handle rod at the end of the pin permits sliding of the latter to disengage the roller from the cam slot, and means for releasably retaining the handle in roller-disengaged position, thereby to interrupt the driving connection from the actuating plate to the driven plate.
35. The combination recited in claim 33, including means for maintaining the lifting lever in partially depressed position.
36. A preassembled unit adapted for installation in a drop type cabinet that has a hinged lid, and a frontcover flap,'said unit comprising a bracket, interconnected driving and driven members including a lifting lever pivoted to said bracket, actuator means adapted for connection to said hinged lid for transmitting a pull to said driving means for moving said lifting lever during one portion of an operating cycle, and for transmitting a push to said driving means for moving said lifting lever during another portion of the cycle, a lifting finger for said front cover flap and means for automatically raising and lowering said lifting finger in timed relation with the movements of said lifting lever.
37. The combination recited in claim 36 in which the 17 18 dn'ving means is connected to move both the lifting lever References Cited in the file of this patent and the lifting finger above their position of use in both UNITED STATES PATENTS their raising and lowering movements. u, T 38. The combination recited in claim 36 which in- 1 gig-g ;i':::'":::'ga eludes spring actuated booster means to facilitate the 5 Smith 1936 lifting of a machine from dropped to operative position, 2,711,940 Hochman June 28, 1955 and 2,712,973 James July 12, 1955
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US861451 *||Apr 5, 1904||Jul 30, 1907||William C Free||Sewing-machine cabinet.|
|US1057809 *||Jun 16, 1906||Apr 1, 1913||Singer Mfg Co||Sewing-machine stand.|
|US2066017 *||Dec 9, 1935||Dec 29, 1936||Nat Sewing Machine Co||Sewing machine support|
|US2711940 *||May 19, 1954||Jun 28, 1955||Hochman Julius C||Drop head machine and booster|
|US2712973 *||Dec 18, 1951||Jul 12, 1955||James Charles C||Sewing machine cabinets and means for elevating sewing machine heads|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US3264046 *||Oct 31, 1963||Aug 2, 1966||Mpi Ind Inc||Appliance supporting cabinet|
|US3986755 *||Aug 25, 1975||Oct 19, 1976||Maruzen Sewing Machine Co., Ltd.||Means for mounting sewing machine in cabinet|
|US4018487 *||Mar 25, 1976||Apr 19, 1977||Keystone Consolidated Industries, Inc.||Cam adjustment for tension spring of sewing machine head lifter mechanism|
|U.S. Classification||312/26, 312/276|
|International Classification||D05B75/06, D05B75/00, A47B29/00|
|Cooperative Classification||D05B75/06, A47B29/00|
|European Classification||A47B29/00, D05B75/06|