US3771329A

US3771329A - Adjusting device for the tightness of the knitting on knitting machines

Info

Publication number: US3771329A
Application number: US00222067A
Authority: US
Inventors: E Krause
Original assignee: SCHIEBER R GmbH
Current assignee: SCHIEBER R GmbH
Priority date: 1971-03-10
Filing date: 1972-01-31
Publication date: 1973-11-13
Anticipated expiration: 1990-11-13
Also published as: SU464130A3; CS157725B2; JPS5138829B1; DE2111553A1; GB1361562A; IT953384B; DE2111553B2

Abstract

Knitting machine needle cam adjusting arrangements wherein a transport nut is moved along a shaft which is turned by a motor which also moves a potentiometer element forming a part of a bridge circuit which controls the motor to one of several optionally selectable positions. The transport nut is arranged to engage a stop on which a spring biased needle cam is mounted, to set the cam position.

Description

United States Patent Krause Nov. 13, 1973 ADJUSTING DEVICE FOR THE TIGHTNESS [5 6] References Cited OF THE KNITTING ON KNITTING UNITED STATES PATENTS MACHINES 1,571,765 2/1926 Felsl 66/75 [75] Inventor; Erich Krause Bopfingen Ge -many 3,035,426 5/1962 Maqueen 66/76 [73] Assignee: Universal Maschinenfabrik Dr. Primary Examiner Ronald Feldbaum Rudolf Schleber Att0rneyJ0seph M. Fitapatrick et a].

Westhausen, Germany [22] Filed: Jan. 31, 1972 57 ABSTRACT PP 222,067 Knitting machine needle cam adjusting arrangements wherein a transport nut is moved along a shaft which [30] Foreign Application Priority Data is turned by a motor Wl'llCh also moves a potentiometer element forming a part of a bridge circuit WhlCl'l Mar. 10, 1971 Germany t. P 21 ll 553.7 controls the motor to one of Several optionally Se]ecta [52] U S Cl 66/78 ble positions. The transport nut is arranged to engage n I s s I s 1 u a on a S rin cam 51] Int. CL... D04b 7/00, D04b 15/36, D 0i1 3 5 /9 9 mounfed to set the campposgition [58] Field of Search 66/77, 78, 76

6 Claims, 4 Drawing Figures 2| @111111111 llr-ill 1/ lo 1k 22 A I, H 33 i r"- J V A PATENTEnnuv 13 I975 3.771, 329

SHEET 2 BF 2 l: z /A ADJUSTING DEVICE FOR THE TIGHTNESS OF THE KNITTING ON KNITTING MACHINES The present invention relates to a device for adjusting the tightness of knitting produced on knitting machines, and particularly flat-bed knitting machines, by changing the position of the knitting machines stitch cams.

In known flat-bed knitting machines the tightness of knitting is adjusted by means of a device of complicated construction provided on the carriage which carries the stitch cams of the machine. The heavy elements of this adjustment device must continuously be moved together with the carriage. In known adjustment devices, wherein a selected stitch cam is shifted in position by means of shift bolts, guidance of the stitch cam presents particularly great difficulties. Since the place for the adjustment of the device must be readily accessible, the shift bolts rest via setting tabs on the surface of the carriage and must transmit the value set to the cam stitch present above the needle bed. Since the shiftable bolts lie in between, the transmission of movement is both difficult and inaccurate. An indication for the reading of the position must furthermore be arranged in a readily visible place, whereby further difficulties in construction and movement transmission result.

It is an object of the present invention to provide a device for adjusting the position of a stitch cam which does not have the disadvantages indicated above and which makes possible an easy and accurate transmission of a preselected position of the stitch cams.

This object is obtained, in accordance with the present invention, by means of an electrically controlled or regulated electric motor which is arranged to effect displacement of the stitch cams.

In one suitableembodiment of the invention the adjustment device comprises a continuously operating electric motor for adjustment of the stitch cams and an electric bridge circuit including an electric displacement pickup and at least one individually adjustable electric setting device by means of which the electric motor is controlled.

The electric setting devices may be potentiometers mounted in a conveniently accessible location. The electric displacement pickup is preferably firmly connected to the stitch cam. The adjustment device of the present invention is preferably so developed that the different electric setting devices are automatically connected in optionally controllable manner with the control apparatus of the knitting machine.

Apparatus according to the present invention can be so constructed that the stitch cam together with its entire adjustment device is supported in such a manner that it can be moved upward against spring action in a lock in a vertical direction by the needle butts of the knitting machine needles. The adjusting device comprises in this connection, for instance, means supporting and guiding of the stitch cam, an adjusting spindle, a displacement pickup and an electric motor.

One advantage of the apparatus in accordance with the invention resides in the fact that the adjusting devices are no longer contained on the carriage, while the electric motor itself together with its corresponding measuring and actuating means is arranged on the carriage.

There has thus been outlined rather broadly the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures for carrying out the several purposes of the invention. It is important, therefore, that the claims be regarded as including such equivalent construction as do not depart from the spirit and scope of the invention.

A specific embodiment of the invention has been chosen for purposes of illustration and description, and is shown in the accompanying drawings, forming a part of the specification, wherein:

FIG. 1 is a schematic wiring diagram for a stitch cam adjustment device according to one embodiment of the present invention;

FIG. 2 is a schematic top view of a removeable part of an adjustment device according to the present invention and showing a control and measuring unit for the positioning of a stitch cam;

FIG. 3 is a top view of an adjusting knob with a vernier scale, for making adjustments to the circuit of FIG.

FIG. 4 is a view, partially in section, of an adjusting device in accordance with the present invention, and showing that device in its upward position.

As shown in the wiring diagram of FIG. I, there is provided a bridge circuit 9 for supplying current to a continuously operating electric motor for the displacement of stitch cams. One half of the bridge circuit 9 comprises one of four manually adjustable selection potentiometers l, 2, 3 and 4 which are arranged in easily accessible fashion on the main body of the knitting machine. Each of the potentiometers l, 2, 3 or 4 can be connected optionally into the bridge circuit 9 by means of a

switch

5, 6, 7 or 8 associated with it. The

switches

5, 6, 7 and 8 are located in the control apparatus of the knitting machine and are, if necessary, automatically selected and actuated. The remaining half of the bridge circuit 9 comprises a displacement pickup 10 which is, for instance, also a potentiometer and is connected with the connected selection potentiometer l, 2, 3 or 4 to complete the bridge. The bridge circuit 9 is fed by a source of voltage 9a.

The displacement pickup 10 which, as is shown in FIG. 2, is firmly connected with the stitch cam 11, is displaced by the rotation of a motor 12 which is controlled via an amplifier 13 corresponding to the detuning of the bridge circuit 9. The motor 12 rotates in a given direction until equalization of voltage has been obtained in the bridge circuit 9 corresponding to the adjustment of the potentiometer l, 2, 3 or 4 connected at the time.

As can be noted from FIG. 2, the stitch cam isguided in a cam plate 14, and is pulled firmly by a tension spring 15 via a stop 16 against a transport nut 17. The transport nut 17 travels on an adjustment spindle 18 which is lightly supported in

bearings

19 and 20. A bevel gear 22, firmly connected with the adjustment spindle 18, is driven by a bevel gear 21 which is firmly seated on the shaft of the motor 12 so that, depending on the direction of the rotation of the motor 12, the transport nut 17, and thus the stitch cam 11, is moved up or down. The displacement pickup is rigidly connected with the stitch cam 11 so that it indicates the exact position thereof.

The potentiometers l, 2, 3 and 4 are each adjusted by means of individual rotary knobs 24 bearing a vernier scale 23, as shown in FIG. 3. The rotary knobs for this adjustment are arranged on the main frame of the knitting machine at a place which is readily accessible.

In FIG. 4 there is shown a view, partially in section, of the adjusting device in accordance with the invention. Since upon the knitting the leading stitch cam must always be swung so high that it does not pull the needles down below cam level, it would be disadvantageous if the stitch cam had to move over a large distance at each point of reversal of the carriage and if its displacement time differed from the actual adjustment time. The entire adjusting device 24 is therefore fastened to two

guide bolts

27 and 28 which are guided in the carriage 26 and are pulled downwardly by a spring 29 at all times in the direction of an arrow A shown in FIG. 4. It remains in this position if the stitch cam lags, i.e. when it pulls down the needles for the stitching. At the point of reversal of the carriage the adjusting device is pressed by an inclined surface (not shown) in the direction opposite that of the arrow A shown in FIG. 4, and an electromagnet 30 shifts a detent bolt 31 into a detent groove 32 in the guide bolt 28. The entire adjusting device is so held that the switch cam 11 can no longer reach a needle butt 33. By this lifting it is possible to effect a new displacement of the stitch cam 11 for the corresponding adjustment of the tightness of the knitting during the stroke of the carriage during which the stitch cam leads.

Having thus described the invention with particular reference to the preferred form thereof, it will be obvious to those skilled in the art to which the invention pertains, after understanding the invention, that various changes and modifications may be made therein without departing from the spirit and scope of the invention, as defined by the claims appended hereto.

What is claimed is:

1. Apparatus for adjusting the tightness of the knitting by changing the position of the stitch cams on knitting machines, such as flat-bed knitting machines, said apparatus comprising an electric motor mounted adjacent to a stitch cam to be adjusted and said motor being coupled to said cam to adjust the position thereof, and an electric motor control circuit for controlling the operation of said motor to adjust said cam to a predetermined position, said control circuit comprising an electric bridge circuit, said bridge circuit including, on one side thereof, an electric displacement pickup firmly connected with the stitch cam, and on the other side, at least one individually adjustable electric setting device via which the electric motor can be controlled.

2. Apparatus according to claim 1, by the fact that the electric setting devices are otentiometers.

3. Apparatus according to claim 1 wherein the electric displacement pickup is rigidly connected with the stitch cam.

4. Apparatus according to claim 1, wherein the electric setting devices are connectable in automatically optionally controlled manner with the control apparatus of the knitting machine.

5. Apparatus according to claim 1, wherein there is provided supporting means by which the entire adjusting device, including said stitch cam, is supported vertically under spring action in a carriage lock in such a manner that it can be moved upward by the needle butts.

6. Apparatus according to claim 5, wherein said supporting means includes guide elements mounted to permit the stitch cam to be adjusted upon movement of the adjusting device to an upward position.

UNITED STATES PATENT OFFICE I, I CERTIFICATE OF. CORRECTION Patent No 3 771,329 Dated November 13 1973 Inventor) ERICH KRAUSE It is certified that error appears in the above identifie d pat ent and that said Letters Patent are hereby corrected as shown below:

Title page I Column 1, item [731 delete "G. m .b.H."

and substitute --KG-. Signed and sealed this 9th day of July 197 (SEAL) V Attest:

I c. MARSHALL DANN MccQr lg I. GIBSON IR. I Attesting Officer 5 Commissioner of Patents FORM PO'IOSO 0'59,

Claims

2. Apparatus according to claim 1, by the fact that the electric setting devices are potentiometers.