US3890807A

US3890807A - Driving mechanism for knitting needle displacement in warp knitting machines, such as raschel machines, particularly

Info

Publication number: US3890807A
Application number: US420795A
Authority: US
Inventors: Johannes Socha; Wolfgang Groth
Original assignee: W Schlafhorst AG and Co
Current assignee: Oerlikon Textile GmbH and Co KG
Priority date: 1972-12-02
Filing date: 1973-12-03
Publication date: 1975-06-24
Anticipated expiration: 1992-06-24

Abstract

A drive arrangement for knitting needles in warp knitting machines. In addition to the up and down motion, a tilting motion is imparted to the knitting needles with the fulcrum at the height of the casting-off edge of a stationary casting-off bar. The drive linkage comprises a crank drive whose rocker arm is connected to a link which is the carrier of the knitting needles. The carrier is rigidly connected to the link at an angle of 110* to 160*. The link has an intermediate pivotally mounted support.

Description

[ June 24, 1975 United States Socha et a].

Patent DRIVING MECHANISM FOR KNITTING 66/86 R 66/86 R 66/86 R 3 570,269 3/1971 Wenrich......... 1.. NEEDLE DISPLACEMENT IN WARP 3,587,252 6/1971 Kohl............. Kohl....................................

MACHINES, PARTICULARLY.

FOREIGN PATENTS OR APPLICATIONS mt t w m 3 mm 0 9 M. t 0 r. 3G m a w 0 8 MW .ah a .Mb e r O t n e V H I H 7 Attorney, Agent, or Firm-Herbert L. Lerner Y n a m r e G o 9 c m &k b i fl a Tw o mmr en Ine h h & m wmm .& e n g i S v A M 7 ABSTRACT 22 Filed: Dec. 3, 1973 121 App]. No.: 420,795

A drive arrangement for knitting needles in warp knitting machines. In addition to the up and down motion, Foreign Appllcauon Priority Dam a tilting motion is imparted to the knitting needles Dec. 2, I972 with the fulcrum at the height of the casting-off edge of a stationary casting-off bar. The drive linkage com- 'Germany.................,.......'... 2259170 prises a crank drive whose rocker arm is connected to a link which is the carrier of the knitting needles. The carrier is rigidly connected to the link at an angle of 110 to 160. The link has an intermediate pivotally mounted support.

[58] Field of 66/86-89 [52] US. [51] Int.

References Cited UNITED STATES PATENTS 4 Claims, 4 Drawing Figures 3,375,682 4/1968 Wcnrich.......;...................... 66/86 R PATENTEDJUN 24 I975 SHEET F/Gjf 1 l DRIVING MECHANISM FOR KNITTING NEEDLE DISPLACEMENT IN WARP KNITTING MACHINES, SUCH AS RASCHEL MACHINES, PARTICULARLY The invention relates to a drive arrangement for the motion of the knitting needles in warp knitting machines, and in particular, Raschel machines, wherein in addition to the up and down motion. a tilting motion is imparted to the knitting needles with their fulcrum at the height of the casting-off edge of a stationary casting-off bar.

More particularly, the invention relates to a novel four lever linkage which is driven by an eccentric mounted crank arm at high speed. The crank arm drives a rocker arm which is pivotally mounted 'on the frame. The rocker arm is connected to and drives a link which is mounted on an arm which is pivotally mounted on the frame, the dimensions of the linkage members are chosen so as to produce a desired compound motion of the knitting needles.

The tilting motion additionally imparted to the knitting needles produces a counter movement of the knitting needles relative to the eye-pointed needles and prevents the mass forces of the guide bars from increasing during the swinging motion of the guide bars. Therefore. it becomes possible to shorten the swing of theiguide bars with a knitting motion which is equivalent to the present knitting process.

It is already known to tilt the knitting needles about a fulcrum at the height of the casting-off edge of the stationary casting-off bar sufficiently far so that the guide bars need to execute only the displacement movement. In this prior device, the tilting motion is generated by a cam mechanism.

The disadvantage of this prior device is the cam mechanism mentioned, which presents considerable difficulties at the high machine speeds now desired because of the high inertial force situation.

It is further known to drive the needle bar with its knitting needles and the casting-off bar, on the one hand, and the guide bar, on the other hand, in such a manner that these elements execute an exclusively counterrotating movement with opposite phase, and therefore produce the counter movement mentioned above. A major shortcoming of the last-mentioned device is caused by the fact that the casting-off bar is not stationary, but participates in the swinging motion of the knitting needles. In addition to an increase of the mass forces, the danger exists here that the loops hanging on the needle shanks are overstretched by several millimeters. Furthermore, the functioning of linear guides, such as are used in the known devices, is restricted at high machine speed due to the inertial forces that appear.

It is an object of the invention to eliminate the shortcomings described above in a drive arrangement for the motion of the knitting needles in warp knitting machines and in particular, Raschel machines.

According to the invention, this problem is solved by providing that the drive arrangement comprises a fourlever linkage which is connected to a crank, which is connected to a rocker arm, which is part of a doublerocker. The double-rocker is connected to a link which is the carrier of the knitting needles. The carrier elements of the knitting needles are rigidly connected with the link at an angle of l lto 160. The use of a fourlever linkage makes possible very high machine speeds. The four-lever linkage is furthermore less sensitive to dust, which can lead to jamming of devices with linear guides.

If according to a further advantageous feature of the invention, a line connecting the frame fulcrum of the rocker, which predominantly determines the tilting motion of the knitting needle, to the head of the knitting needle is approximately perpendicular to the line connecting the two end positions of the linkage points of the rocker-link junction, the remaining movement of the needle at the casting-off edge is only a few tenths of a millimeter. Overstretching of the loops hanging on the needle shanks is thereby avoided and a pronounced dwell at the highest point of the knitting needle movement is obtained.

Accordingly, a principal object of the invention is to provide new and improved knitting machine means.

Another object of the invention is to provide new and improved knitting machine means which provides a compound lifting and tilting motion to the knitting needles.

Another object of the invention is to provide new and improved knitting machine means which provides a combined lifting and tilting motion to the knitting needles comprising a four lever linkage driven by an eccentric drive at high speed.

Other features which are considered as characteristic of the invention are set forth in the appended claims.

Although the invention is illustrated and described herein as embodied in a particular embodiment. it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.

The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. 1 is a side view of a drive arrangement, partly in cross section, with a knitting needle in the lowest position.

FIG. 2 is a side view according to FIG. 1, in which the knitting needle is in the uppermost position.

FIG. 3 is a motion diagram for the knitting needle and swinging motion of the guide bars, and

FIG. 4 is a polar diagram of the knitting needle motion.

FIG. 1 shows a crank drivel, comprising the main shaft 2, an eccentric 2' firmly connected therewith and the connecting rod 3. The four-lever linkage 4 consists of the rocker arms 5 and '6, mounted on frameconnected fulcrum points 7 and 8, respectively. The

arms

5 and 6 are connected to the link 9 at the linkage joints l0 and 11 respectively. The rocker arm 5 is provided with an extension 5, which makes a connection with the crank drive 1 via the pin 12. The link 9 also has an extension 9' mounting the carrier elements for the knitting needles 13.

The carrier elements consist of the support post 14 firmly connected in the extension 9 and a fastening rail 15 connected thereto, for the needle bar 16. The mountings 17 for the knitting needles 13, which in the embodiment shown here consist of latch needles, are tightly bolted to the needle bar 16. The stationary casting-off bar 18 is mounted next to the knitting needle 13. The eye-pointed needles 19 of two guide bars, not shown, are shown guiding the thread above the castingoff bar 18. Mounted next to the casting-off bar 18 is the take-off cylinder for the weaved product.

Elastic diaphragms

23 and 24, for protection against dust and flying lint, are connected to the support post 14 and

member

21, 22 of the drive housing.

In FIG. 1 the junction point 10 has reached its end position. which determines the lowest position of the knitting needle 13. FIG. 2 shows the highest end position of the four-lever linkage 4, the junction point 10, and the other, already mentioned parts. In FIG. 2, the knitting needle 13 has reached its highest position and also the farthest excursion of the tilting motion of the needles about an assumed fulcrum at the height of the stationary casting-off edge 18.

In FIG. I the end position of the junction point 10' reached in FIG. 2, is indicated by dash-dotted lines. It will be seen clearly that the line connecting the frame point 7 and the head 13' of the knitting needle 13 is approximately perpendicular to the connecting line 25 between the junction points l0, 10 in the two end positions. In FIG. 2 the angular position of the rigid connection between the link 9 and the carrier elements for the knitting needles 13 is shown by the angle 26.

FIG. 3 shows the motion of the knitting needles 13 resulting from theindividual phases of the knitting process by means of a motion diagram. The motion consists of a component in the direction x and a component in the perpendicular direction v as functions of rotation indicates the curve of the swing of the eyepointed needles 19. The motion diagram shows that up to the angle of rotation a 80, corresponding to the position of the main shaft 2, the knitting needle is moved only in the direction y, i.e.. the knitting needle is moved vertically .upward. In the position a 80 the underlaying motion is completed. The eye-pointed needles 19 then swing in the direction toward the head of the knitting needle. The head of the knitting needle 13 in turn moves toward the eye-pointed needles 19 be cause of the motion now beginning in the direction FIG. 4 shows particularly clearly the entire cycle of the resulting knitting needle motion in .r and v directions in a polar diagram.

The drive arrangement according to the invention has the already mentioned advantage, which is that the residual motion of the knitting needle at the casting-off edge is only a few tenths of a millimeter and overstretching of the loops hanging on the needle shanks is avoided. This makes additionally possible a particularly great latitude in placing the drive with a warp knitting machine or Raschel machine. Thus, for instance, a mirror-inverted arrangement of the coupling of the rocker arm 6 with the crank drive 1 producing the drive motion is also possible. The drive arrangement can of course, be used in addition, to latch and point needles, also for capillary, slider or other known needle types.

We claim:

1. Drive means to provide a tilting motion in addition to an up and down motion to knitting needles, comprising a crank drive, including a crank shaft, a first frame mounted rocker arm connected to the crank shaft, a link member having one end connected to the other end of said first rocker arm. a second frame mounted rocker arm pivotally connected to an intermediate point on said link, a carrier of knitting needles rigidly connected to the other end of said link at an angle of 1 10 to to the axis of said link, the lengths of said crank shaft, rocker arms and link being chosen to impart an up and down motion and a tilting motion to said carrier.

2. Drive means according to claim I, wherein the line connecting the frame point of said rocker arm, which predominantly determines the tilting motion of the knitting needle, with the head of the knitting needle is approximately perpendicular to a line connecting two end positions of the junction point of the rocker arm and link.

3. Drive means as in claim I, wherein an intermediate point on said link is pivotally mounted on a member, the other end of said member being pivotally mounted on the frame.

4. Driver means as in claim I, wherein said crank shaft is driven by an eccentric drive.

i l l=

Claims

1. Drive means to provide a tilting motion in addition to an up and down motion to knitting needles, comprising a crank drive, including a crank shaft, a first frame mounted rocker arm connected to the crank shaft, a link member having one end connected to the other end of said first rocker arm, a second frame mounted rocker arm pivotally connected to an intermediate point on said link, a carrier of knitting needles rigidly connected to the other end of said link at an angle of 110* to 160* to the axis of said link, the lengths of said crank shaft, rocker arms and link being chosen to impart an up and down motion and a tilting motion to said carrier.

2. Drive means according to claim 1, wherein the line connecting the frame point of said rocker arm, which predominantly determines the tilting motion of the knitting needle, with the head of the knitting needle is approximately perpendicular to a line connecting two end positions of the junction point of the rocker arm and link.

3. Drive means as in claim 1, wherein an intermediate point on said link is pivotally mounted on a member, the other end of said member being pivotally mounted on the frame.

4. Driver means as in claim 1, wherein said crank shaft is driven by an eccentric drive.