US 2483138 A
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Description (OCR text may contain errors)
Sept. 27, 1949.
s. H. HELMER AUTOMATIC ACCESSORY F0R1 SEWING MACHINES 5 Sheets-Sheet 1 Filed April 23, 1947 m 12 I L a:
0 w, A W L H n 8 a W m 3% M 0. m 7 m n 2 A J 5 g nn v m H r0 I p 1949- G. H. HELMER 2,483,138
AUTOMATIC ACCESSORY FOR SEWING MACHINES Filed April 23, 1947 s Sheets-Sheet 2 W14, MML
ATT ENEYJ Sept. 27, 1949. G. H. HELMER 2,483,138
AUTOMATIC ACCESSORY FOR SEWING MACHINES Filed April 23, 1947 5 Sheets-Shet s 87ATION#1 sTAT/0-#2 8 ESTHER HELE H ADM/MIST ATR/X- ATTOZNEK! G. H. HELMER AUTOMATIC ACCESSORY FOR SEWING MACHINES Sept. 27, 1949. i
5 Sheets-Sheet 4 Filed vApril 23, 1947 m m 2 H5 Maw RHM m mm 66 N Patented Sept. 27, 1949 UNITED STATES OFFICE AUTOMATIC ACCESSORY FOR SEWING MACHINES Grover H. Helmer, deceased, late of St. Louis Park, Minn., by Esther Helen Helmer, special administratrix, St. Louis Park, Minn., assignor to Munsingwear, Inc., Minneapolis, Minn., a
corporation of Delaware Application April 23, 1947, Serial No. 743,300
This invention relates to improvements in control and auxiliary mechanisms of sewing macontrols for starting and stopping the sewing machine. Thus, in routine stitching operations, it is not only necessary for the operator to insert the material but then to start the machine at the 7 leading edge of the material, guide the same during stitching, and then to stop the machine at the trailing edge. Close coordination and considerable manual dexterity has been a prerequisite for operators doing these routine tasks.
It is an object of the invention to provide improved controls for initiating starting when the material is inserted to be sewn and for providing a controlled stop as soon as the trailing garment edge has passed beyond the stitching position in the machine.
In other routine operations, as in applying bindings, headings, decorations, strips or the like, or where certain seam operations are carried out, it is desirable to cut the binding or trim or to cut or notch the garment edge just as the trailing edge of the garment or garment piece passes beyond the stitching position. To accomplish this it has previously been the practice to provide a cutter in the form of a stationary and cooperating movable shear blade situated immediately behind the position of the needle bar or presser foot and to provide a manual or pedal actuator by means of which the operator may accomplish the severance or notching as the trailing garment edge has been stitched. The timing of this operation has been entirely under operator control and consequently this added, necessarily precisely timed operation has imposed still another burden on the already burdened operator, with the result that irregular work and excessive waste (which has had to be removed in subsequent operations) has more frequently been the result than otherwise.
. t is another object of the invention to provide an improved control for sewing machines and 12 Claims. (Cl. 112219) cutting or notching of individual pieces of material or the pieces in a series while sewing is carried out.
In addition to the foregoing, it is also an object to provide a combined automatic and superimposed operator control so that the operator may instantly superimpose operator control upon the automatic operations.
Additional objects include the provision of improved control, photo-electric and combined electrical and mechanical mechanism.
Other and further objects of the invention are those inherent in the apparatus herein illustrated, described and claimed.
The invention is illustrated with reference to the drawings in which Figure 1 is a front elevational view of a sewing machine in which the invention is incorporated;
Figure 2 is a partial sectional view taken in the direction of arrows 22 of Figure l, illustrating certain of the controls;
Figure 3 is a fragmentary side sectional view taken in the direction of arrows 3-3 of Figure 1;
Figure 4 is a partial rear elevational view taken in the directionof arrows 4-4 of Figure 3;
Figure 5 is afragmentary sectional plan view taken in the direction of arrows 5-5 of Figures 3 and 4;
Figures 6 and 7 are a pair of isometric views of the stitching, feeding and cut-01f mechanisms and certain of the'photo-control devices, illustrating various phases of operation of the invention; and
Figures 8 and 9 are related wiring diagrams of the apparatus.
Throughout the drawings corresponding numerals refer to the same parts.
Referring to the drawings, particularly Figures 1 through 5, the factory type or high-speed sewing machines to which the invention is applicable consist of a usual frame composed of legs H] which are fastened together by a rear frame l! and a top work board l2 upon which the sewing machine head mechanism generally designated I3 is mounted. A frame 15 carries'a hinge mounting it of the drive motor generally designated l8. As usually constructed, the drive motor is of the constantly rotating type and is provided with a built-in clutch-brake mechanism is operating through suitable controls, hereinafter described, quickly to start and stop the drive pulley as which, through the belt 2|, drives the sewing machine operating pulley 22.
The sewing machine head mechanism has the tion. If desired, a presser foot lifter mechanism can be used.
The quick-starting, high-speed operation and quick-stopping of the pulley 2B: is accomplished by the clutch-brake mechanism generally designated i9. mounted a bracket 48 which serves as an anchor for the spring 41. The lower end of the spring 4! is connected to the clutch-brake operating member 42 which has an outwardly extending apertured extension 44 through which a control L rod 65 extends; The control rod 45 is coupled to the member M by a pairof initially compressed springs d! and -48, the Spring 48 being adjustably tensioned by the nut 39 which holds the spring through the washer 50; Similarly, spring 41 is held by the adjustably positionable stop collar 55 which holds the washer 52. The lower end of rod 45 hooks into an eye in lever 53-.
Referring to Figures 1, 2 and 3 particularly, it will be noted that the mounting board which is a part of the machine frame, is provided with two bifurcated pivot brackets, viz. brackets 55 and 56. Upon the bracket 55 there is pivotally mounted a lever 58 which has its left end, as shown in Figures 1 and 2', pivoted at 5? to the movable core Bl of a solenoid 62, the solenoid 62 being mounted underneath the board 32. When the solenoidv 62 is energized the lever 58 is moved up in the direction of arrow 63 to the position shown in Figure l, and when de-energized the lever 58 falls in the direction of arrow 64, thus allowing the core of the solenoid to drop to the dotted line position. The end 85 of the lever 58 carries a pivot bolt 66 which serves as a floating or movable pivot for the lever 53 to the left end of which, as shown in Figure 2, the clutch-brake operating rod 45 of the motor drive is attached. The right end of lever 53, as shown in Figure is pivotally connected at 53 to the right end 69 of a lever ill which is: pivoted at its mid-portion to the bifurcated mounting bracket 58. The left end H of the lever ii! is connected b means of the link 12' to the clutch-brake pedal control 14 which is also pivoted for pedal operation on frame rod 36.v
The operation of these linkages is as follows: Since lever is pivotally mounted at E5 and 58 upon the levers 58 and; Hi. respectively, it follows that the left end of lever 53 is under the joint control of the levers 58 and ill. When the solenoid E2 is (ls-energized, there is no a preciable retaining force on the core 51.. and hence the left end of the lever 58 is free to move up and down, due to its weight and to the reactions hereinafter explained, it moves downwardly in the direction of arrow (54. to the dotted line position of core. Under these conditions, if the pedal id is depressed to the: Run position, the machine nevertheless does not start. Depressing pedal M nulls rod #2 downwardly and moves the left end 1! of the lever 19 downwardly and raises the right end 69, which accordingly tends to pivot the lever 53 about either the control link 45 or the pivot bolt 65. The. resistance of spring ll (motor control Figure 3) is sufficient that it holds Upon the motor there is fixedly 1.-
rection of the arrow marked Run.
the clutch-brake operating member 44 at a datum position (brake on; clutch disengaged), as shown in Figure 3. Accordingly, the rod 35 is fairly well held and, therefore, the movement of the pivot 88, Figure 2,. upwardly due to pedal movement as explanied merely causes the pivot 65 to move upwardly a proportionately smaller amount and the solenoid 6i depressed a little lower. Therefore, unless solenoid B2 is energized, the depression .of operator pedal 74 does not initiate operation of the machine.
When solenoid $2 is energized, the core 6! is pulled upwardly in the direction of arrow 63 to the full line position shown in Figure l, which then establishes the pivot Ell at a fixed position, and hence, since the bracket 55 is likewise fixed, the pivot 56 therefore also becomes fixed so far as this phase of the operation is concerned. If, under these conditions, the pedal M is depressed to the Run position and the rod 72 drawn down, the upward movement of the right end 69 of the love l9 causes the corresponding right end of lever 53 likewise to be moved upwardly, and since the pivot 66 isfixed, the left end. of the lever 53 is depressed and the operating rod 435 drawn down until the spring 48 overcomes the resistance of spring ti and moves the lever mechanism l ld2 downwardly in the di- When this occurs, the clutch of drive l9 is engaged and the brake of the drive is released with the result that rotation of the constantly rotating motor is transmitted through the operating clutch to the pulley 2d and the sewing machine is rapidly driven. Likewise, assuming the solenoid 62 to be energized, if the pedal 74 is lifted to the Stop position, the rod 45 and intervening linkages move the lever 44 inthe direction of the arrow marked Stop (Figure 3) and the clutch of drive I9 is disengaged, the brake of the drive mechanism is engaged and the pulley 20 is brought rapidly to a complete stop. If, while the machine is running and while pedal M is held down in the Run position, the solenoid 62 should be tie-energized, the effect of springs ii! and 4!, as transmitted through the linkages, immediately causes the left end of lever 53 to move downwardly even though pedal 74 is continued in the depressed or Run condition. This allows the pivot 55 on lever 58 to move upwardly and permits the rod 45 to'move upwardly to the top position, thereby causing the drive pulley iii! to stop, regardless of whether the foot pedal M is or is not likewise raised. It will thus be apparent that deenergization of the solenoid 62 causes immediate stopping of the machine and that the operator likewise immcdiaetly stop the machine by raising pedal M. In order that the machine may operate it is necessary that the solenoid. 52 be energized and that the pedal M be simultaneously depressed to the Run position.
When in the sewing operation, it is desirable to cut off or notch a portion of the material at a definite place with reference to the trailing edge or a portion of the trailing edge of the material, there is provided a cut-01f mechanism generally designated 29. The cut-oil mechanism consists of a bracket 30 which is solidly mounted upon the machine frame. Upon the bracket there is a solidly mounted stationary cutting knife 3! and a pivotally mounted cooperating cutting knife 32. The knife 32 is pivoted at 33 and is provided with a coil spring 34 which normally raises the cutting end of the knife 32 in the direction'of the arrow 35. Opposite the cutting end; the knife 32 is provided with an operating foot 36 under which the end 3! of the operating lever 38 protrudes, the lever 38 being pivoted at 39 to the frame 30 of the cut-off mechanism. The free end of the lever 33 is connected by an operating rod I5 which extends downwardly and is connected to the front end of a lever I6 that is pivotally mounted at 'I'! on the bracket I8. From this same end of the bracket there is downwardly extending rod 80 which is coupled to the operator treadle 8!, the treadle 8! being pivoted on the frame rod 36 so that when the rear portion of the treadle is depressed so as to pull the rod 89 downwardly in the direction of arrow 82, the motion is transmitted through the links 80 and I5, thus causing the free end of lever 38 of the cut-off mechanism to be likewise drawn down in the direction of arrow 84. This lifts the end 3'! of that same lever and lifts the operating foot 36 of the cut-off blade 32, thus causing the cutting edge 85 to be moved downwardly scissors-like against the cooperating cutting knife 3 I. Accordingly, any material running through the space 8! between the cutting edges is cut. If the edge only of a wide strip of material is running through this space, it is notched or slit. The cooperating cutting knives 3! and 85 may be shaped as desired to cut merely a slit or to form any configuration of notch needed for the particular garment operation.
The operating lever'lfi has its rear portion 89 connected to thecore 90 of a cutting solenoid 9!. When the solenoid 9! is energized, the core 90 is pulled upwardly, and this causes the front end of the lever "IE to be pushed down in the same manner as would be accomplished by treadle operation, and the cutting blades arelikewise actuated for the cutting operation. The lever IE is provided with a side arm 92 which is ar} ranged to press downwardly upon the operating stem 93 of a microswitch 94 when the lever I6 is actuated to cutting position. Thus, when the treadle 8! is depressed or when the solenoidfi! is energized, thelever I5 is moved downwardly at its front end to accomplish the cutting operation and the microswitch 94 is simultaneously actuated to open the circuit it controls. When the cutter knife 32 is up (not cutting) switch 94 is closed.
The photo-electric controls for the starting, stopping and cutting operations include a first or station No. 1 light source 95 which is suitably mounted by means of bracket 9! on the head of the machine. The light source 95 projects a light beam 99 downwardly upon the highly polished spot I on the sewing machine. If desired, a metal part of the sewing machine may be chromium plated and polished to high brilliance or a mirror may be set in at the spot I00. The spot I00 is in the path of movement of the material being sewn as it moves along the line I!!! against the presser foot 28 to. the stitching station defined by the needle bar 26. The light of beam 99 is normally reflected by the spot"!!! so long as no material is passing throughthe machine and after reflection follows along the path I832 to the station No. 1 photocell I03. The photocell I83 is likewise suitably mounted by means of bracket use on the sewing head.
A second light source I at station No. 2' is mounted by means of bracket I56 on the sewing head and projects light in the direction/of beam 38 against a highly polished surface I09 closely adjacent the end of the stationary cutting knife 3! and from the reflected surface I09 the light is returned in the direction of beam I III to the second or station No. 2 photocell I I I which likewise is mounted by means of bracket I I2 upon the cutter head. The polished reflective surface I89 may likewise be a chromium plated or silvered mirror or reflecting prism and is in a position such that it is normally covered by the material being. sewn as the material leaves the presser foot 28; The reflective surface IE9 is positioned so that when the trailing edge of the garment uncovers the reflective surface and light is again transmitted from light source I05 to the photoe cell III, actuationof the cutting or notching knife 32 ensues. The knife 32 is down when the station No. 2 photocell is lighted and up when that photocell is dark.
For purposes of illustration herein, a garment H4 is illustrated as having an edging strip or heading H5 in the process of being attached thereto. The heading material H5 is arranged to be'fed by means of a guide II? which feeds the heading material as a flat strip to the material piece !!4 immediately in advance of the presser foot 28. The, guide I I! extends around to the front and to the right, as shown in Figure 1, to a spool stand II8 upon which the edging or heading strip H5 is carried in spool form. It will be appreciated, of course, that the specifically illustrated operation is only one of a wide number of operations which can be carried out in accordance with the principles of this invention. Thus, decorative material in strip form may be applied at the edge or at any portion of a garment. Also, headings oredgings may be applied or the edge of a garment merely folded over to form a seam edge, all depending upon the particular operation carried out.
Referring to the wiring diagrams, Figures 8 and 9, Figure 8 illustrates the power supply re lays and various controls and the method in which they operate theclutch and cutting solenoids to manage the operation of the machine. At the right, as shown in Figure 8, there are pro- I vided two terminal blocks H3 and H9 having six terminals each. Terminal block H3 connectsto terminal IIB of station No. 1 and terminal block H9 connects to terminal N9 of station No. 2. There is a light source, photocell and preamplifier for each station No. l and No. 2, and as these are identical, only one need be described. Figure 9. illustrates the photocells, light sources and pre-amplifiers of each of the stations No. land No. 2. It will be understood that'two diagrams, as' shown in Figure 9, are required to complete the entire circuit arrangements, one. being connected to the terminal block II8 of Figure 8 and the other being connected to' the terminal block H9 of Figure 8, one of the'diagrams of Figure 9 being for the first light source and the" first photocell I53 and theother being for the second light source I05 and the second photocell i I I.
Referring to Figures 8 and 9, the circuits are supplied through an ordinary llil-volt or 220- volt alternating current power source L! and L2 which feed through fuses I253 to a threepole, double-rthrow manual switch indicated under the bracket I2! which serves to connect the apparatus for automatic or manual operation, as hereinafter described. When the common operating lever I22 of switch I2! is pushed, the individual switches I23, I24 and I 25 are simultaneously moved downwardly from the automatic to the manual contacts, and when in the down position the circuits are energized for purely manual operation.
Line LI is connected to switch blades I23 and W2, whereas line L2 is connected to switch blade I25. Line LI also extends at I5I through the amplifier on-01f switch I58 and thence through line I51 and fuse I26 to the primary winding I21 of transformer generally designated I28 and thence by line I29 and then through the second pole I38 of the on-off switch and line I3I to the power supply L2. Whenever the machine is to be used for automatic operation, the amplifier on-off switch mil-I39 is closed and the transformer I28 and amplifier circuits are energized. From the automatic contact I33 of the switch I2I, line I 32 extends through the coil I35 of the cutter operating solenoid 9| and thence to junction I36 from which the circuit continues through line I31 to contact I38 of three-pole, double-throw gang switch generally designated I48, thence through blade IQI of said switch and line I 32 to the blade I i i of relay contacts generally designated B2B (relay B2B contacts). The blade I62 of relay R23 is in the up position when the station N0. 2 photocell H8 adjacent the cutter blade is darkened, as when material is passing through the machine; the circuit is continued through contact Hi5, line I 66, junction I41 and thence through line I48 to automatic terminal I69 of switch I2I and thence to line L2. Referring back to junction I36 (shown in Figure 8 immediately under cutter operator solenoid), a circuit also extends over line I58 to the movable contact blade I52 of the relay contact group generally designated RIB (relay I; B contacts), which is responsive to the lighting of the station No. 1 photocell I93. When the photocell I63 is dark, which occurs when material is passing into the machine to be sewn, the contact blade I52 of relay RI is likewise in the up position and thus in engagement with the contact I53 from which a circuit extends through line I54 to the contact I55 which cooperates with blade I4I of the gang switch I68.
From junction I 58 on line LI a circuit extends to contact blades I24 of the automatic-manual switch I2I, and from blade I24 a circuit continues when the switch I2I is in the up or automatic position to contact I59 and thence over line I69 to the contact I6I on line I62. A circuit is also established from line LI to junction I6I when the automatic-manual switch I2! is in the depressed position, in which case the blade I23 of that switch is in contact with the manual setting contact I93, which is connected by line I 94 to the junction 16!. Hence, junction I6I is energized at the potential of line LI for either automatic or manua condition and a circuit extends over line I62 to the coil I65 of the drive clutch colenoid 62 which, when energized, lifts its solenoid core SI up- Wardly, as previously described. From the coil I65 the circuit extends to junction I66. From junction I66 there are four circuits. Thus, a circuit extends from over line I61, junctions I83 and I98, through continuation of line I91 to the manual contact I69 which cooperates with the switch blade I 25 of the manual-automatic switch I2I.
When the switch I2I is depressed to the manua position, the blade I25 is brought into engagement with contact 59 and line L2 potential is thus applied to the drive clutch solenoid coil I65. As previously explained, line LI potential is also applied through contact I63 and .8 hence in the manual position of switch I2I the drive clutch solenoid coil is continuously energized.
From junction I66 a circuit also extends through line I61 to junction I68, thence to contact I10 of the relay contacts generally designated RZA (relay R2; A contacts). When the relay contact I of the group RZA is in the up position (which occurs when the station No. 2 photocell III] is dark, as when material is passing through that station), contact III is in engagement with contact I18 and the circuit thence continues over line I12 to junction I13, thence through junction I14 to contact I15 of the gang switch I99. When the gang switch is moved to the left, viz. to the method No. 1 position, the cooperating blade I16 engages contact I15 and the circuit then continues over line I11 to junction I41 from which the circuit continues via line I48 to automatic contact I49 of "switch I2I and then through blade I25 to line L2.
From junction I13 the circuit extends to the method No. 1 contact I18 which cooperates with the blade I19 of the gang switch I60. From lblade I19 the circuit extends through line I88 to the contact blade IBI of the relay contact roup RIA (relay RI; A contact) which is in the up position when the first photocell I93 of station No. 1 is in the darkened condition which occurs when material is in the machine to be stitched. The circuit continues from blades i8I to contact I82 and thence to junction I83 on line I61.
From junction I14 on line I12 a circuit extends to the contact blade I85 of microswitch generally designated 94 which is operated by the lever 16 of the cutter solenoid, Figure 2, as previously described. When the cutter operating solenoid is energized, the contact blade I85 is down and no circuit is completed therethrough. When the cutter solenoid is not energized the contact blade t 85 is up and completes a circuit through ccntact I86 to line I61.
In Figure 8 relay RI has two contacts A and B. Likewise, relay R2 has two contacts A and B. All of these contacts are in their up positions when the photocells which control the energizetion of these relays are in their darkened condition, as occurs when material interrupts the light supply to the corresponding photocell.
The transformer I28 is provided with a secohdary coil I88 which is connected through line I99 to the coil I90 of relay RI, the opposite terminal of which is connected through line I9] to terminal AI of the connector block II8 for station No. 1. From terminal BI of the connector block a circuit extends through line I92 to junction I93 (which is connected through condenser I94 to ground I95) and from junction I93 through line I96 to the opposite terminal of the secondary windin I88. The transformer likewise has a secondary Winding I98 which connects through the line I99 to one terminal of the relay coil 269 of relay R2 which is connected through line 25H to the contact A2 of the connector block H9 for station No. 2. From contact B2 of the connecting block a circuit extends over line 262 to junction 293 (which is connected through the condenser 266 to ground 205) and from junction 293 the circuit extendsover line 2I6 to the opposite terminal of the secondary winding I98.
The remaining terminals of the connector blocks H8 and. I I9 are voltage supply terminals. Thus, the filament winding 286 of the transformer is connected through lines 261 and 228 to the filament terminals Fil. of both of the connector blocks H8 and H9 and thus supp y fil ment voltage to the light sources and all tubes in the pre-amplifiers at stations No. 1 and No. 2. It will be understood, of course, that the filament transformer also supplies the filaments of all tubes in the control apparatus. The transformer secondary winding 209, which is grounded at its mid-point 2H), operates through the full wave rectifier tub 2I I to supply direct current to line 2 I 2 which is smoothed out and regulated through the network H3 and voltage regulator tube 2E5 so as to supply direct current positive at about 150 volts to line 2I4 which is connected to the D. C.+ terminal of each of the connector blocks I I8 and H9. The ground terminal G of the connector block is the negative line of the direct current supply.
Referring to Figure 9, from the filament terminals of the connector blocks I It (or I as) lines 220 and 22I extend to the light source 55 (or I55) at stations No. 1 and No. 2. It must be understood that an identical diagram as in Figure 9 is used for each light source photocell and preamplifier, stations No. 1 and No. 2. The light from source 95 (or I05) is projected through the lens system 222 onto the reflective surface which is either the surface IE0 or surface I59, Figures 6 and 7, and is thence reflected back against the photocell I52 (or III). The direct current positive terminals of the connector block H8 or M9 is connected through line 224 and junction 225 to the positive terminal 226 of a potentiometer resistor 22! which is grounded at terminal 228 within the apparatus and also to the ground terminal G of the connector block. From midpoint 229, line 230 extends to the anode 232 of the photocell I03 (or III) and from the cathode 233 of the photocell the line 234 extends through junctions 235 and 236 to the control grid 237 of the pentode amplifier tube generally designated 238. The cathode 239 of the tube is connected through junction 240 and resistor 24H to terminal 228. Grid bias potential is maintained by an adjustable point 242 on the resistor 24! from which a line extends through the resistor 243 to junction 236. The resistor 243 is variable by means of the shunt 244 connected to junction 235. Suppressor grid 245 of the pentode is connected to the cathode. Screen grid 245 which is maintained positive via line 224, junction 225 and line 270, is also connected through line 24! and junctions 248 and 249 to the anode 256. The anode 25E! of tube 238 is coupled by condenser 252 to junction 253 on the control grid 254 of second stage amplifier generally designated 256. Negative bias of grid 254 is maintained by a circuit extending from junction 253 through the resistor 25! and line 258 to junction 240 and thence through resistor 24I to negative terminal 228 of the potentiometer. The cathode 26!) of tube 255 is connected through junction 26I and line 252 to 6 Operation Figure 9 is representative of the light sources, photocells and pre-amplifiers of both stations Nos. 1 and 2, and as they operate in the same manner only one need be explained. The explanation will, therefore, refer to station No. 1 having light source and to cooperating cell H53 which ultimately control relay RI through circuits established through the connector block ii8-Ii8'. In the following explanation it will be assumed that the on-ofi switch I55, Figure 8, is closed and with the automatic-manual switch l2I in the upper or automatic position. The transformer I28 of Figure 8 and all circuits served by it are therefore energized, and filament voltage is accordingly impressed upon the terminals Fil. of Figures 8 and 9 with the result that the cathodes of the amplifier tubes 23% and 255 and the light sources of both stations Nos. 1 and 2 are energized. The operation of the stations No. l and No. 2 light sources and pre-amplifiers is therefore as follows:
A light beam is normally returned against the photocell 153 of station No. 1 when no material is passing through the machine and the photocell signal from photocell I53 is impressed upon the grid of tube 238 and is amplified and the amplified signal impressed upon the control grid 254 of tube 255 causing the latter tube to become conductive or to fire (thyratron tube), thereby in effect establishing a circuit between terminals AI and B5. A circuit is thus completed from terminal A! of connector II8 through line I9I, coil I95 of relay RI, line I89, transformer secondary 288, line I96 to terminal 13! and is closed through the cathode-anode circuit of tube 255 in the pre-amplifier Figure 9. Relay winding I95 of relay R1 is accordingly energized and moves its RIA contacts IBI and its RiB contact l52 to the down position in Figure 8. It may be noted parenthetically that all of the relay contacts l'II, IBI, I52 and M4 for both relays are in the down position of Figure 8 when the photocells which actuate them are lighted and are up when the photocells are dark.
Photocell ill of station No. 2, being similarly illuminated, in effect establishes a circuit between terminals A2 and B2 of connector H9, thus similarly energizing the coil 280 of relay R2. This serves to move the RZA movable contact Ill and the R215 movable contact I44 to the down position inFig'ure 8.
Method No. 1.In the following explanation it will be further assumed that the gang switch I4!) is moved to the left as shown in Figure 8 to the method No. 1 position, in which position contact I4I engages I55, I16 engages H5 and I19 engages I18. 'It is also assumed that the operator holds treadle M in the down position. In the method No. 1 mode of operation one piece at a time is handled by the machine. The piece is entered into the machine and a tape, decorative strip or heading is stitched on, the machine being automatically started as the leading edge of the piece is entered at station No. 1 and the piece is then run through until the trailing edge of the piece reaches the station No. 2 photocell III. The machine then automatically stops and the trim, binding or heading I5 is automatically cut off. This mode of operation is accomplished as follows:
With the photocells both illuminated and before the material H4 is entered (position 2', Figure 6), both relays RI and R2 are energized and their contacts therefore assume the down position of Figure 8. Under these conditions a circuit is established from line LI, contact I22 of switch I2I to contact I33, line I34, coil I35 of the cutter operating solenoid, junction I35, line I 55, relay contact I52 which is then down and in engagement with contact I53, line Id,"
contact I55, which is then engaged by gang switch contact I lI, line I42, relay contact Ice (B2B) which is likewise down and in engagement with contact I45, lines I46 and I48, through contacts ms and I25 to line L2. The'cutter solenoid is hence energized and the knife blade 32 is down. When the cutter solenoid I35 is energized, the microswitch 94 has its contact 685 in the down position (Figure 8) and hence does not establish any circuit through line 61.
The garment III! of Figure 6 is initially held in the full line position 2' of Figure 6. In this position both photocells are illuminated and the previously described relay positions therefore are maintained. As the garment is entered to position 272 it covers reflecting surface I60 and therefore darkens photocell I 03. Consequently, the coil i851 of relay BI is deenergized and relay contacts lSI (RIA) and I52 (RIB) are moved to their up positions in Figure 8, the relay contacts l'iI (REA) and His (R213) meanwhile being maintained in the previously described down positions. As relay RI de-energizes and RIA contact IBI closes upon I82, a circuit is established from line LI, junction I58, switch I2I, contacts 124-459, line I60, junction IEI, line IE2, clutch solenoid coil I65, junction I68, junction H33, contacts I82 and I8I (RIA), line I88, contacts H9 and I78 of gang switch IQO, through junctions I73 and I14 and contacts H5 and lit of gang switch I48, line I'I'I, junction I ll, line I ls, contacts M9 and I25 to line L2. The clutch and brake mechanism I9 is therefore operated and the sewing and material feeding operations ensue. At the same time the opening of B5B contacts I52 and I 53 breaks the cutter solenoid circuit previously described, thus permitting the cutting knife 32 to lift as the leading edge of the material IM and the binding II 5 approach station No. 2. The de-energization of the cutting solenoid also operates microswitch as causing its contact I85 to close on contact I86, which establishes a shunt circuit from terminal E66 of the clutch solenoid winding I65, through line 567, contacts 185 and I86 of the microswitch, to junction I14. This parallels the previously described circuit through contacts HH and I82 (REA), line I80 and contacts I18 and IE9 of gang switch I 40.
As the material II- assumes position 273, photocell III of station No. 2 is also darkened causing relay R2 to die-energize and move its contacts R-ZA and R213 to the up positions of Figure 8. Contact RZA establishes another shunt circuit to maintain the clutch solenoid energized, this circuit being from terminal I66 of the clutch solenoid winding t65, through line I 6! to junction I68, thence through contacts no and Ill (R2A), line I12, etc., as previously described. This has no immediate effect. Relay contacts I64 and I45 (B2B) also open, but this likewise has no immediate effect because the cutter solenoid circuit was previously opened by the opening of contacts 52-453 (RIB) when relay RI was de-energized.
As the trailing edge of the material passes be yond station No. 1, thus uncovering reflective surface IIlIl, relay RI is again energized. This causes contacts NH and I82 (RIA) to open, but since the clutch solenoid circuit is maintained via contacts I19 and I'll (RZA) and. also by microswitch contacts I85 and I86, the clutch solenoid remains energized and the sewing operation continues. The closure of relay contacts I52 and E53 (RIB) prepares but does not establish the previously described circuit to thecutting solenoid winding 535 since this circuit is still maintained open at contacts I44 and I45 (B2B).
As the stitching of the material Iill is completed and it reaches position 27 3 of Figure 6, the trailing edge of the material uncovers the reflective surface I89 of station No. 2, thus causing relay R2 to be re-energized and its contacts R2A and R23 to be moved to their down positions of Figure 8. When this occurs, contacts Ill? and H! (R2A) open to break one of the two remaining previously described parallel circuits which has maintained the clutch solenoid winding i635 energized. The closure of the B2B contacts Hi l and I45 of relay R2 establishes a circuit for the cutter solenoid winding I35 as follows: From line LI switch contacts I23 and I33, line I3 3, winding I35 of the cutter solenoid, terminal l36, line I50, RIB contacts I52 and I53, line I 54, contacts MI and I55 of gang switch MEI, line I 32, B2B contacts I54 and H35, line 546, junction I47, line M8, switch contacts I59 and I25 to line L2. The cutter solenoid then operates and cuts the material II and/or the binding, heading or decorative strip I I 5. The energization of the cutter solenoid !35 also causes the opening contacts I and E86 of microswitch 94 and the clutch solenoid IE5 is therefore de-energized to stop the machine and hold the stop.
The operation is thus completely automatic and can be repeated time after time. The operator may, however, superimpose control on the operation by movement of treadle I4, for upward movement of treadle at any time causes the sewing operation to stop and starting can be delayed as desired until the treadle it is depressed.
Method No. 2.--In this type of operation the pieces of material being sewn are fed in one at a time as the work progresses with a little space, preferably one-half inch to three-quarters inch, between the trailing edge of one piece and the leading edge of the preceding piece so as to allow a little opening between them. The binding, heading or trim II 5 is, of course, continuous and the material pieces sewed to it thus form a continuity up to station No. 2. In this operation the leading edge of the first piece initiates the sewing operation by covering the reflective spot at station No. 1 and sewing continues (of course, under operator control by treadle 14) as lon as subsequent pieces of material continue to cover Station No. 1. As each break between the pieces reaches station No. 2, the strip H5 is automatically severed and as the trailing edge of the last piece reaches station No. 2, the operation ceases. This operation is achieved as follows:
The gang switch I40 is moved to the right to the method No. 2 position with the result that contact I79 closes upon contact 275, contact E16 closes upon contact 211 and contact IGI closes upon contact I38. It will be observed that this isolates relay contact RIB (I52 and I53), relay contacts R2A (I?!) and I'll) and the mircoswitch contacts I 85 and 86, all of which serve no purpose in method No. 2 operation. The automaticmanual switch I2I is, of course, still in the up or automatic position and switch I56I3il is closed. It is also assumed that the operator holds treadle I l down, thus conditioning the clutch control for starting or pushes treadle I l down after the first piece of material in the series is positioned inplace adjacent the tape binding or strip II5 and starts the operation, which is initiated by the joint operation of the operator treadle 14 and theenergization of clutch 13' solenoid 62 (winding I), the circuit for which is as follows:
Before the first piece of material is moved into position, the photocells at both stations No. 1 and No. 2 are illuminated and relays RI and R2 are energized, as previously described, causing contacts RIA (contacts IBI and I82) and RZB (contacts Hid and I65) to move to the down position. The cutter solenoid is thus energized through a circuit from line LI, contacts I23 and I33, line I30, winding I35, line I31, gang switch contacts I38 and iii, line I42, relay contacts Hi l-I05 (B2B), line M6, junction I41, line I08, switch contacts I49 and I to lin L2. The cutter sole-- noid winding I is thus energized and the knife 32 is down. With contacts RIA (I8! and I82) in the down position, the clutch solenoid is de-energized, with the result that the machine is stopped, but as soon as the leading edge of the first piece of material IM is in place (position 212, Figure 6), the photocell I03 at station No. 1 is darkened, relay R2 is die-energized and contacts RIA (ISI and I82) close and establish a circuit to the clutch solenoid from line LI, contacts I20 and I59 of switch I2I, line I60, junction IGI, line I62, clutch solenoid winding I 65, junction I06, line I6? to junction I83, RIA contacts WI and I82; line I80, gang switch contacts I10 and 275, line 2176, gang switch contacts 2?! and I76, line I'll, junction Idl, line I48, contacts I49 and I25 of switch I2I to line L2. This energizes the clutch solenoid and if the operator then moves treadle I0 to the down or Run position, or does so as the material is arranged, the sewing operation starts.
As the leading edge of the material reaches station No. 2 and covers the reflective surface I09, photocell III is darkened and relay R2 is deenergized, thus breaking the previously described circuit through contacts R23 to the cutter solenoid winding I35. This raises knife 32 and the leading edge of the material 0, and strip II5 sewed thereon enters space 81 between the cutter elements.
The sewing operation continues until the trailing edge of the first piece of material I I4 uncovers the reflective surface I00 of station No. 1, whereupon photocell I03 is illuminated and relay BI is energized and RIA contacts I8I and I82 open, thus stopping the sewing operation with the trailing edge of the first piece of material H0 just beyond the refiective spot I00. The operator then inserts another or second piece of material immediately behind the first piece with just a little space therebetween (one-half inch to three-quarters inch) and as photocell I03 of station No. 1 is again darkened, relay RI is again de-energized and contacts RIA (I8I and I82) close, to again energize the clutch solenoid winding I65 and sewing is resumed. Skillful operators become so adept at inserting successive pieces of material that there is scarcely a halt in the sewing operation, yet the machine does halt for the unskillful or tired operator so that there is never an excessive amount of space between successive pieces.
As the trailing edge of each piece in the succession reaches station No. 2, light is momentarily reflected from mirror I09, thus illuminating photocell I I I at station No. 2. This causes energization of relay R2 and consequent closure of contacts B2B (I and I) to re-establish the circuit to cutting solenoid winding I35 which, therefore, operates to move knife 32 downwardly to sever the strip III between successive pieces. The severance is made while sewing continues,
since operation of the cutting solenoid does not interrupt the clutch solenoid circuit.
Manual operation-For purely manual operation switch I2I is moved to the down or manual position which establishes a circuit from line LI, through switch contacts I23 and IE3, line I64, line I32, clutch solenoid winding I65, junction I66, line I61, switch contacts I59 and I25 to line L2. The clutch solenoid is thus energized and moves the clutch control linkages so that by appropriate operation of treadle I0 the machine can be started and stopped at will. When thus operating manually, any cutting or severing action is accomplished by treadle 8|, since the cutting solenoid winding is maintained open at contacts I33 and I43 of switch I2I. Switch I56-I30 is, of course, opened to de-energize transformer I28 and all circuits served thereby.
As many apparently widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood the invention is not limited to the specific embodiments herein except as defined in the appended claims.
What is claimed is:
1. In a sewing machine having means for feeding the material therethrough and simultaneously sewing it, the combination comprising a cutting device mounted on the machine for cutting the material after it has been sewn, and spaced light source means and cooperating photocell means having a light path between them that is in the path of movement of the material when it is moved through the sewing machine, and means responsive when the material fed through the machine changes the amount of light transmitted from the light source to the photocell for operating said cutting device.
2. Theapparatus of claim 1 further characterized in that the light source and photocell are both mounted above the path along which the material is fed through the machine, and a light reflective surface is mounted below said path for reflecting the light from the light source back to the photocell when not covered by the material fed through the machine.
3. In a sewing machine having a power source, stitching and material feeding mechanisms op erated by the power source, the combination comprising a first light source and photocell mounted on the machine and having a first light path therebetween which is capable of being interrupted by the material fed through the machine as it approaches the stitching mechanism, a second light source and photocell mounted on the machine and having a second light path therebetween which is capable of being interrupted as the material leaves the stitching mechanism, cooperating means responsive when the material fed through the machine interrupts the first light path for causing the power source to operate the material feeding and stitching mechanism and responsive when neither the first or second light paths are interrupted for discontinuing the operation of the machine.
4. The apparatus of claim 3 further characterized in that the power source is constantly rotatable and the stitching and feeding mechanisms are driven therefrom through a clutch controlled by said cooperating means.
5. The apparatus of claim 4 further characterized in that said clutch is provided with a manual control which in one position enables the cooperating means to effect operation of the machine and in another position stops the maaasaacs 15 chine regardless of the operating conditions of said photocells and cooperatingmeans.
6. The apparatus of claim 3 further characterized in that material severing means is provided for severing at least a portion of'the material as it leaves the stitching means, said cooperating means being operable to cause operation of said material severing means while the feeding and stitching are in progress when a discontinuity in the material causes a change in light transmitted along the second light path as the material is fed through the machine.
7. The apparatus of claim 6 further characterized in that manual means is provided which in one position enables the cooperating means and light sources to control the operation of the feeding, stitching and severing mechanisms and which in another position completely stops the operation of the machine.
8. hi a sewing machine having a constantly rotating power source, stitching and material feeding mechanisms, a clutch connecting said power source and mechanisms for operating the same, an operator control, a photo-electric control having a light source means and light responsive means with light paths therebetween, said photo-electric control being characterized in that the light Source means and light responsive means include a first light source and a cooperating photocell positioned so that a first light path therebetween is in a position to be interrupted by the leading edge of a piece of material being entered into the machine for sewing and a second light source and cooperating photocell positioned so that a second light path therebee tween is in a position to be interrupted as the leading edge of a piece of material being sewn leaves the stitching mechanism and which interruption ceases when the trailing edge of the material leaves said stitching mechanism, and means connecting the operator control, the photoelectric control and the clutch which is conditioned to engage the clutch when the operator control is operated and the first light path .is interrupted by movement of a piece of material to be sewn through the normal path of movement for sewing and to disengage the clutch When either the operator control is operated .to disengaging position or the material being sewn moves so as to leave the second light path free as the material leaves the sewing position.
9. The apparatus of claim 8 further characterized in that the machine is equipped with a material severing arrangement in the path of movement of the sewn material as it leaves the stitching mechanism and means operable when the second light path is not interrupted to actuate said material severing arrangement.
'10. The apparatus of claim 9 further characterized in that the material severing arrangement comprises a stationary knife mounted in the path of movement of sewn material and immediately behind the stitching mechanism and a cooperating movable cutter knife actuated by electromagnetic means, said second light path including a light reflective surface adjacent the tip of the stationary knife.
11. The apparatus of claim 10 further characterized in that the material severing arrangement is also provided with a mechanical connection to a foot treadle for direct mechanical operation.
12. The apparatus of claim 8 further characterized in that the means connecting the operator control, the photo-electric control and the clutch includes a levering arrangement comprising a first lever pivoted to the machine and connected to the operator control so as to be operated thereby, a second lever likewise pivoted to the machine and operated by electromagnetic means which is connected to and responsive to change in condition of the light path of ,the photo-electric control, and a third lever pivoted to the first and second levers and linked to the clutch.
ESTHER HELEN HELMER, Special .Admim'stratrizr of the Estate of Grover H. Helmer, Deceased.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,800,629 Helwig Apr. 14, 1931 1,989,294 Ross et .al Nov. 13, 1934 2,418,356 Kleber Apr. 1, 194.7