US 2166636 A
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y 1939- s. s. MARCUS ET AL 2,166,636
WIRE KNOTTING MACHINE Filed Oct. 27, 1937 2 Sheets-Sheet 1 INVENTORS Samuel 5. Marcus amuel Kra/cauer ATTO RN EYS July 18, 1933.
s. s. MARCUS El AL 2,156,635
WIRE KNQTTING MACHINE Filed Oct. 27, 1937 2 Sheets-Sheet 2 INVENTORS Samuel S. Marcus SamueZ Krakauer M ra ATTORN EYS Patented July 18, 1939 UNITED STATES PATENT OFFICE WIRE KNOTTING MACHINE Application October 2'7, 1937, Serial No. 171,258
This invention has relation to wire wrap knotting machines of the type which are generally employed for the purpose of anchoring free ends of coiled upholstery or furniture springs to the convolutions adjacent said ends by wrapping or coiling the same thereabout and the invention comprehends improvements therein for overcoming certain difficulties hereinafter enumerated.
In the types of these machines which are now in general use the clutch is controlled by a foot actuated pedal and it has been observed that considerable waste results from the tendency of even the highest skilled operators to actuate the pedal before the end of wire terminal and/ or the adjacent convolution are properly positioned, it being essential that both be precisely emplac'ed to avoid spoilage of the spring.
Another frequent shortcoming on part of an operator is his failure to hold the spring in proper position until the automatic clamp grips and retains the same in place. This failure is due mainly to the fact that the table bed upon which the end convolutions of the spring are seated initially moves rearwardly a short distance before the clamp functions and it is, therefore, necessary for the operator to continue to hold the spring in position during said initial movement of the table bed. By experience it has been found that it requires not less than three and frequently as long as six months for the average operator to become proficient in learning to operate the machine, While the spoilage of springs and the waste resulting from improper positioning of the spring coils and failure to hold the same a in position until clamped, averages from five percent to twenty per-cent of the total output depending upon the length of service of the operator.
In order to overcome the above recited disadvantages and to render the machine more efiicient and safer, and less tiring on the operator, the invention comprehends the elimination of the foot pedal actuation of the clutch and the provision of an electrically operated means for actuating the clutch which means is arranged in an electrical circuit having one or more switches located at the critical points where they are employed for the closing of the circuit only when the spring coils and terminals are properly positioned.
As a further feature, the invention comprehends an auxiliary clamp means which is instantly rendered effective to clamp and retain the spring in position on the table bed when the clutch is rendered active and prior to the movement of the table bed so as to clamp and retain the spring in position until the usual automatic clamp functions. This auxiliary clamp means is so constructed and arranged as to be actuated by a cam provided on the present machine thereby obviating the necessity of providing any additional working parts for the actuating of the auxiliary clamp.
Other objects of the invention reside in the provision of the specified improvements and their construction and arrangement in such a manner as to require but slight alteration in the existing machines when applied thereto as an attachment therefor, or the incorporation of the same in newly built machines, while said improvements are capable of economical production and attachment or incorporation.
With the above enumerated and other objects in view, the invention is more particularly disclosed in the following specification, illustrated in the accompanying drawings and pointed out in the appended claims which cover variations and modifications falling within the scope of the invention.
In the drawings:
Fig. 1 is a fragmentary front view of a knotting machine embodying the improved features constituting the present invention.
Fig. 2 is a fragmentary side view thereof.
Fig. 3 is a fragmentary plan view of the same.
Fig. 4 is a fragmentary perspective view of a spring illustrating the wire knot connecting the terminal of the end convolution with the next adjacent convolution.
Referring to the drawings by characters of reference, Ill designates the frame of the wire wrap knotting machine, ll the table bed which is carried by a support l2 pivoted as at I3 to the frame and provided with a rearwardly directed arm I4 which is provided with a cam roller l5 engaging in the cam groove I6 of a rotary cam l1 0 which is secured to a transverse shaft l8 journaled for rotation in the frame.
The table bed has secured on its upper surface, a block I9 having a groove in its upper surface which groove together with the rear face 2| of the block constitute gage means for properly positioning a coil spring thereon for wrapping or knotting the terminal of the spring about the second convolution, it being understood that the end convolution is seated on the upper surface of the table bed II and against the rear surface of the block IS with the second or next adjacent convolution disposed within the groove 20.
The bending or wrapping die or element which is of generally cylindrical form having peripheral gear teeth 26 is journaled for rotation in a fixed bearing carried by the frame of the machine and is provided with a slot 21 extending from the axial center thereof radially outward and opening through its periphery. The
terminal wrapping or coiling element is also provided with a shoulder 28 parallel to the slot 2'! and alongside thereof, it being understood that, as usual, the slot '21 receives therethrough the second convolution A of the spring, while the shoulder 28 is adapted to engage with the terminal B of the end convolution C after said terminal has been bent at an angle by the rearward movement of the table bed which rearward movement is effected by the rotation of the cam H.
In the present machine, the transverse shaft I8 is coupled with a rotary power shaft .35 by means of a clutch 36 which is rendered active by an electrically operated device such as a solenoid 31, as distinguished from the ordinary knotting machine in which the clutch is actuated by the foot of the operator. In this instance, the solenoid 31 is arranged in a circuit including a source of supply 38 from which a conductor 39 leads through the winding of the solenoid and thence extends to the fixed arm 40 of a switch, the movable arm 4| of which is normally disposed out of contact with the fixed arm and is controlled by a push rod 42. The push rod 42 is provided with an abutment terminal 43 which is so arranged as to be engaged by the end of the terminal B of the end convolution C to effect the flexing of the movable switch arm 4| and its contact with the fixed arm 40 when the spring terminal is in a proper position to be bent and wrapped by the bending and wrapping die 25.
From the switch arm 4| a conductor 44 leads to a fixed switch arm 45. of a second switch. The second switch has a movable switch arm 46 which is actuated by a push rod 41, the terminal of which push rod is located in the bottom of the slot 20 of the block l9 on the table bed so that the movable switch arm is moved into contact with the fixed switch arm 45 only when the second convolution A of thespring is properly positioned within the groove 20. From the movable switch arm 46 of the second switch, a conductor wire 48 leads to the other side of the source of supply and it will thereby be observed that the solenoid and the two switches are arranged in series in the electrical circuit and that the circuit will be closed to actuate the solenoid only when the terminal B and convolution C are properly positioned on the table bed. When the operator has thus properly positioned the spring, the circuit will be closed and the solenoid will actuate the clutch 36 to couple the power shaft 35 with the shaft 8. This obviates the necessity of the tiresome practice of the operator having to bear his weight on one foot while actuating a foot pedal, while the arrangement of the switches at the critical points of contact of the terminal and spring convolution insures the production of a perfect spring and knot having the required number of wraps, thereby greatly reducing, if not entirely eliminating, spoilage of the springs and the waste incident thereto.
The machine is provided with the usual clamp 50 at the terminal of a lever fulcrumed as at 52 on the arm I 4 and which clamp is swung downwardly into clamping position as the table bed is swung rearwardly by'the riding of the upper edge of the clamp lever 5| under an actuating roller 53 journaled on a fixed pin 54. In practice it has been found that the clamping action is delayed until the table bed has partially moved rearwardly thus requiring the operator to hold the spring convolutions in place on the bed I against the rear surface 2| of the block and in the groove while the table bed is moving rearwardly and up to the time when the clamp 50 becomes efiective. This has presented a major difiiculty to new operators and not infrequently accounts for a considerable amount of spoilage of springs even to experienced operators. In order to overcome this difliculty, an auxiliary means is provided for causing the clamp 50 to become effective immediately and independent of and prior to the engagement of the clamp lever 5| with the roller 53, This auxiliary means consists of an arm 55 which is fulcrumed intermediate its ends as at 56 to the frame of the machine and which is provided with a cam pin 51 at its rear terminal engaging the outer periphery 58 of the cam H at a point where the initial movement of said cam will cause the forward downturned end 59 of the arm 55 to move the clamp 50 downwardly into efiective position. This instantly causes the spring to be clamped in position on the table bed II and relieves the operator of the difficulty of manually holding the spring in place while the table bed is moving.
From the foregoing it will, therefore, be observed that the number of difficulties in the operation of a wire wrap knotting machine have been overcome by the improvements specified.
What is claimed is:
1. In a wire wrap knottlng machine of the type which includes a rotary device for wrapping the terminal of the wire about an adjacent portion thereof, a movable table bed having gage means thereon against which the wire is impinged when located in proper position for wrapping a predetermined length of the free end, drive means for actuating the table bed and wrapping device, a clutch for connecting said drive means to actuate the table bed and wrapping device; an electrical circuit including an electrical device for rendering said clutch active, and a normally open switch adapted to be closed by the impingement of the end of the terminal of the wire thereagainst so as to effect the wrapping of a uniform predetermined length of the terminal about the adjacent portion of the wire.
2. In a wire wrap knotting machine, the combination with the swingable table bed thereof having gage means against which a portion of the wire is adapted to be impinged and a fixed member having a rotary wire wrapping element and a stop against which the terminals of the wire impinge to gage the length of the terminal portion to be wrapped about an adjacent portion of the wire, and mechanism for efiecting the swinging of the table and the rotation of the wrapping element; of an electrically actuated device for rendering said mechanism active, a circuit including in series said device, and a pair of normally opened switches, one located adjacent the table bed gage means and the other located adjacent the fixed member wire terminal stop, said switches adapted to be actuated to close the circuit when the wire and its terminal are impinged against the table bed gage means and the fixed member terminal stop.
3. In a machine for knotting the terminal of the end convolution of a coiled spring about the next adjacent convolution including an electrically actuated clutch for rendering the machine active, an electric circuit including said clutch and a switch so located as to be engaged and closed by contact of the end of the wire terminal therewith when the same is positioned in the machine to wrap a uniform predetermined length thereof about said next adjacent convolution.
SAMUEL S. MARCUS. SAMUEL KRAKAUER.