US 2448639 A
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Description (OCR text may contain errors)
Sept. 7, 1948. w c s 2,448,639
FABRIC CONTACTING CIRCUIT CLOSER FOR KNITTING MACHINES Filed Aug. 10, 1946 2 Sheets-Sheet 1 INVENTOR Sept. 7, 1948. w c s AN 2,448,639
FABRIC CONTACTING CIRCUIT CLOSER FOR KNITTING MACHINES Filed Aug. 10, 1946 2 Sheets-Sheet 2 M/(H/YEL WA (HS/7H INVENTOR BY l Patented Sept. 7, 1948 OFFICE FABRIC CQNTACTING CIRCUIT CLOSER FOR KNITTING MACHINES Michael Wachsman, Brooklyn, N. Y.
Application August 10, 1946, Serial No. 689,735
' 1 Claim. 1
The object of this invention is to provide a novel and improved fabric contacting circuit closer for knitting machines for closing anelectric stop circuit to actuate a knitting machine stopping device when a tear, run, a droppedstitch or other irregular or abnormal condition appears or occurs in the knitted fabric.
In the operation of knitting machines which include electric circuit closing devices it is of the utmost importance that such devices be most carefully protected against deposits and accumulations of dirt, paraffin, fluff from the fabrics and yarns which unavoidably result from the operation of the machines and hinder or even prevent the efiicient operation of the electric circuit to stop the machine promptly in cases of trouble. It is a prime object of this invention to provide electric circuit closers in which the contacting terminals are adequately enclosed and protected. The invention is embodied in fabric contacting circuit closers as hereinafter described and as illustrated in the accompanying drawings in which Fig. 1 is a view of a circuit closer enclosed in a protecting box, the cover of the box being removed.
Fig. 2 is a sectional view of Fig. 1 taken on the line 22 thereof with details omitted.
Fig. 3 is a view similar to Fig. 1 but shows a circuit closer having two fabric contacting detectors.
Fig. t shows a circuit closer having a single fabric contacting detector with the circuit closing mechanism enclosed in a special inner protective casing.
Fig. 5 illustrates a modification of the circuit closer shown in Fig. 4.
Fig. 6 shows a circuit closer adapted for high voltage operation to avoid the use of batteries and transformers.
Fig. '7 is a diagrammatic view of circuit closing device in which fabric contacting detectors eral disclosure and operation of suchdevices'. A knitting machine is provided with a mechanism for shifting the belt or clutch whereby to -stop the machine when troubles occur. Such mechanism is actuated by an electric circuitwhic'h is normally open. Certain elements inconta'ct with the fabric are employed to close the stop circuit when abnormal conditions occur in the fabric and such abnormalities are detected by such elements. This, in brief, is the underlying principle of operation of knitting machine stop motions whether they be yarn detectors or 'fabridcontacting detectors.
Referring to the drawings the fabric is represented at it In Fig. 1, a detector I2 is slidably mounted ina box it. The detector carries an insulated contact l5 which is connected by a spring 7 if: to an-adjustable springsupport ll in'thr'eaded engagement with a screw shaft 18 operable from outside the box by a hand knob [9 to adjust-the tension of the spring. A fixed contact 20 is adjustably mounted in the box. The contact is movable in a slot 2i and secured by a nut 22 in adjusted position. The contact 29 is completely insulated by insulating members 24 which also serve to close the slot 21 to prevent the entrance of dirt.
The box may have an attaching'lug 25 for mounting the device in a suitable position on the knitting machine. The detector I2 is preferably a thin flat member having a bent contact head 26. The contact 26 is connected via a battery to an electromagnet 28 which, when energized, operates theshipping lever 38, or clutch lever as the case may be, of the usual stop mechanism, not shown. The operation is well known in the art. The other side of the circuit is grounded on the machine.
The detector I2 is held in normal frictional contact with the fabric by the spring I 6-;- When a fault occurs in'the fabric the spring operates the detector to move the contact [5 into-engagement with thecontact 29 to close the circuit to energize the magnet'and the knitting machine stops.
Fig. 3 illustrates a device in which twodetectors are mounted in the box [4. In addition to the mechanism shown in Fig. 1, the device in Fig. 3 includes a detector 32 which is relatively long and extends upward into contact with the fabric. Thus a double protection is provided and a greater area of fabric is under control, the detector 32 being offset with respect to the detector 12 as shown. The detector 32 is mounted on a shaft 33 under the control of a spring 34 attached to a spring support 35 adjustably carried by a screw shaft 36. The shaft 33 also carries a contact 31 two insulated terminals 62 and 63.
adapted to engage a fixed contact 38 which is similar to the contact 26. The operation by either or both detectors i2 and 32 serves to close the electric circuit to stop the machine.
In Fig. 4 the detecting mechanism includes contact members which are completely enclosed within a separate protective casing. In this illustration the detector 46 is of circular form ending in a pointed detector head 4!. To the detector is secured a toothed contact member 42 in the form of a ring and the detector is urged into contact with the fabric by a spring 13. The contact 42 is grounded on the machine and is adapted to engage a second similar fixed contact M. The latter is wholly insulated by suitable insulation as at 45, 45. The contact 44 is adjustable with respect to the contact 42 by means of a spring 'll and threaded nut 48, the spring acting between the casing 46 and the contact &4. The nut 48 carries a terminal 49 for the electric connection to the stop circuit. The entire unit is placed within a box 50 for attachment to the knitting machine. The casing 46 serves the double purpose of protecting the contacting elements against dirt and also in preventing ill advised attempts to repair and tamper with the mechanism by unskilledlabor. The casing is preferably made of thin metal and the end 52 is soldered to the casing after the other parts have been placed within the same.
In the modification illustrated in Fig. the
one ring formed contact member 55 is in the form of a cup having an annular wall 56 adapted to enter a circular groove 57 in the other contact element 58. The toothed contact elements in Fig. 4 as well as the elements 55 and 58 inv Fig. 5 afford unusual good contact for closing the circuit.
In Fig. 6 the electric current supply is direct from the line wires 66 to the magnet BI and to The detector 96 may have any suitable form. It carries a negative and a positive contact disk 64 and 65, respectively. The disks are insulated as shown at 66 and 6?. The detector with the contact disks 64 and 65 is held in frictional contact with the fabric I6 by a spring 68. The circuit is closed by a contact bridging fixed contact member 69 which is adjustable by a spring 16 and threaded nut H as shown. The contact 69 is wholly insulated by insulation as at l2, 73. The contact members 64 and 65 have contacting flanges l4 and 15, respectively. 7 When a fault occurs in the fabric the spring 63 operates the detector to the right in the drawing. The two flanges M and 75 contact with the two terminals 62 and 63, the current passing to the two contacting disks 64 and 65. The latter are bridged and the circuit closed by the disks contacting the fixed element 69 as will be understood. The entire circuit closing unit is enclosed within a dustproof casing 18 and no electric current passes through the knitting machine. Batteries and transformers are therefore not required.
In Fig. 7 fabric contacting detectors are used 4 on both sides of the fabric. To the usual dial shaft 86 of the knitting machine there is secured an inner contact ring 8i and to the needle cylinder frame, indicated at 82, there is secured an outer contact ring 83. Each ring, Fig. forms an annular chamber 84, Fig. 9, in which there are mounted as many detectors as may be required. Each detector carries a contact 86 and is controlled by a spring 8l. Within each circular chamber at there is mounted an insulated contact ring 86 to which current is supplied as shown. The detectors are placed in staggered relation as shown in Fig. 8.
When a fault occurs in the fabric, one or more tive springs 87 to close the circuit by engagement of the contacts 86 with the electric ring 88. Obviously, a greater area of fabric may be brought under control by the closely placed detectors 85.
In Fig. 10, the detector 96 within the box 9| is connected by a chain, wire orlink 94 to the shipping lever 36 so that when the detector is operated as described above in connection with Fig. 1 not only will the circuit be closed to actuate the shipping lever, but the latter will be mechanically operated. This feature is provided for double protection in operation.
The circuit closers disclosed herein may be used with stationary or rotary knitting machines in any combination desired. The enclosing of the contacting elements insures freedom from dirt and insures efficient operation.
A fabric contacting circuit closer for knitting machines comprising a box, a detector slidably supported in the box, a spring in said box secured to said detector for holding the same in normal frictional contact with the fabric, a normally open electric stop circuit for the knitting machine, a fixed contact in said circuit supported in the said box, a contact member carried by said detector and adapted to engage the said fixed contact to close the said circuit when an abnormal condition in the fabric causes a termination of the said normal frictional contact between the detector and the fabric and means in the said box for regulating the tension of the said spring, said means comprising a spring tension regulating member secured to said spring. a shaft in threaded engagement with said member to actuate the same and a knob on said shaft for operating the later from outside the said box.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,286,913 Barratt Dec. 10, 1918 2,091,467 Carhart Aug. 31, 1937 2,357,712 Vossen et a1 Sept. 5, 1944