US3759069A

US3759069A - Control apparatus for the pattern drum of a knitting machine

Info

Publication number: US3759069A
Application number: US00243325A
Authority: US
Inventors: I Ziprian; H Scheffler; K Bannehr
Original assignee: Wirkmaschinenbau Karl Marx Veb
Current assignee: Wirkmaschinenbau Karl Marx Veb
Priority date: 1972-04-12
Filing date: 1972-04-12
Publication date: 1973-09-18
Anticipated expiration: 1990-09-18

Abstract

A pattern drum is intermittently rotated forward or backward, by variable numbers of steps, by a control star rotor having uniformly spaced pins. A pair of pin engaging control members can be set to control such a pin for forward motion (by activating one member of the pair), or for backward motion (by activating the other member of the pair), or for zero motion (by deactivating both members). For these purposes, the control members rotate with an annular guide system past the control star and drum.

Description

States atent 1 Scheffier et al.

[ 1 Sept. 18, 1973 CONTROL APPARATUS FOR THE PATTERN DRUM OF A KNITTING MACHINE [75] Inventors: Ilolger Scheffler, Lichtenstein;

Konrad Bannehr, Leukersdorf; Ingo Ziprian, Gersdorf, all of Germany [73] Assignee: VEB Wirkmaschinenbau,

Karl-Marx-Stadt, Germany [22] Filed: Apr. 12, 1972 [21] Appl. No.: 243,325

[52] U.S. Cl 66/50 B [51] Int. Cl D04b 9/00 [58] Field of Search 66/50 B, 24, 25, 66/154, 156

[56] References Cited UNITED STATES PATENTS 3,416,332 l2/l968 Joseph 66/50 B 3,587,253 6/1971 Guell 66/50 B Primary Examiner-Ronald Feldbaum Attorney-Albert C. Nolte, Jr. et al.

[57] ABSTRACT A pattern drum is intermittently rotated forward or backward, by variable numbers of steps, by a control star rotor having uniformly spaced pins. A pair of pin engaging control members can be set to control such a pin for forward motion (by activating one member of the pair), or for backward motion (by activating the other member of the pair), or for zero motion (by deactivating both members). For these purposes, the control members rotate with an annular guide system past the control star and drum. 7

9 Claims, 7 Drawing Figures Patented Sept. 18, 1973 3,759,069

3 Sheets-Sheet l T :1- l' mfg Patented Sept. 18, 1973 5 Sheets-Sheet 2 Patented Sept. 18, 1973 3 Sheets-Sheet 5 CONTROL APPARATUS FOR THE PATTERN DRUM OF A KNITTING MACHINE BACKGROUND AND NATURE OF THE INVENTION For driving the pattern drum of a machine which produces pattern knitwear, mechanisms have been used thus far which had serious problems and defects. In the first place, it always was difficult to turn the pattern drum by a step or steps of uniform angular length. Most of the devices for limiting such a step were brakes; these are subject to heavy wear and tear and therefore are in need of frequent andexpensive readjustment. Another problem is that, when the machine runs fast, jolts are encountered when starting or ending a turning step. I

The invention overcomes these difficulties by a new construction of the so-called control star and of the systems utilized for moving it. In a preferred embodiment of the invention this star has four pins. Two of them normally are held in an annular channel, which rotates relative thereto, while the other two ride on the outside of the channel. At one point the channel is interrupted by insertion of a star turning mechanism, comprising four pin engaging members. One or two of these are raised into engagement with successive pins of the star. If one of these members is raised the star is turned by 90; if two are raised it is turned by 180. The drum is correspondingly promoted by one or two control steps. Preferably, the pin engaging parts of the control members have pin impact and pin guiding surfaces corresponding respectively to the impact path of one pin and the corresponding motion of'a followingpin, thereby preventing uncontrolled impact motions even in the case of very rapid operation.

IN THE DRAWINGS FIG. 1 is an elevational sectional view of apparatus incorporating the invention, the section being taken along lines l1 in FIG} 3;

FIG. v2 is a fragmentary sectional view taken along lines 2-2 in FIG. 1;

FIGS. 3 6 are plan views of the apparatus showing successive positions of relatively movable parts thereof; and

FIG. 7 is a top view of the apparatus.

DETAILED DESCRIPTION In the preferred embodiment described herein actual rotary motion is performed by annular groove or channel 21 and control members 17 to 20 thereof, while pattern drum land control star 12 are stationary, the motion of the first-mentioned parts being performed in the direction of arrow A, shown in each plan view figure. In order to avoid the need for an over-sized illustration, we assume that the observer moves along with the parts 17 to 21 which accordingly appear'i'n the same position in the successive plan view figures, while accordingly

parts

1 and 12 appear to move in a direction opposite to the arrow A.

Pattern drum 1, best shown in FIG. 1, is mounted on vertical shaft 2 for the purpose of turning the drum in successive steps. The turning steps of the drum are performed in order to reciprocate pushers which in turn move knitting needles according to a predetermined program for the production of pattern fabric; these lat ter parts and products need not be shown herein, as

I art.

many types of them are known to persons skilled in the A simple gear mechanism described hereinafter connects drum I with control star 12 so that this star can turn the drum. The star is built in the form of a circular plate P, having four pins 13 to 16 secured to the periphery thereof at uniform angular distances from one another and projecting a short distance from the underside of the plate.

In a location generally below these pins there are provided four control members 17 to 20. One of them (19) is shown only in part in FIG. I. They are vertically movable between certain limits, by mechanisms known by persons skilled in the art, in a guide system shown only schematically as G (FIGS. 1 and 2). As already indicated, these members are inserted as part of annular channel 21. Control members 17, 18 are generally inside the circle of this channel while the other two are outside of this circle (FIGS. 3 to 6).

When all control members 17 to 20 are in their lower position, none of them engages any of pins 13 to 16. Therefore, in such position of the control members there occurs no motion of control star 12 and pattern drum 1 but the control members merely pass the control star.

The operation is different when, for example, control member 17 is lifted into the position shown in FIG. 1. This member then encounters pin surfaces of the control star during the relative motion of these parts and turns the star and thereby the drum. If both members 17 and 18 are in such position (FIG. 3) as shown, thestar is turned by two successive steps, in the rotary direction indicated byarcuate arrow B in FIG. 4. On the other hand, if inner control members 17, 18 were lowered and outer control member 19 and/or 20 were raised, the star would be turned to make one or two' steps in the opposite rotary direction.

According to the invention two diametrically opposite pins of the control star,

forexample pins

13 and 16 according to FIG. 3, are normally guided in annular groove 21A of guide channel 21. This guidance protects control star 12 and pattern drum 1 against any accidental, for example vibratory turning throughout the normal operation of the machine, particularly since the star is additionally guided by pins l4, 15 which slide or run along the outsides of channel 21.

The successive relative motions will be understood readilyon consideration of FIGS. 3 to 6. As shown in FIG. 3, control star 12 still is guided by channel 21.

However, the channel is aboutto free the pins of the star for rotary motion, in the rightward travel A of channel and control members, and there is a short gap C between the illustrated leftwardly facing end of the channel and the opposite right-hand end of the control members 17 to 20.

'As these members come closer to the control star, FIG. 4, an impact surface 22, upstanding from a right surface part of raised control member 18, encounters pin 15 and initiates clockwise turning B of the control star. No interfering impact occurs on opposite control member 20, which is in low position and does not engage any of the pins of the control star.

As shown in FIG. 5, pin 15 has performed part of its clockwise motion and thereby pin 13 has engaged upstanding contact surface 23, the two

surfaces

22, 23 being the two sides of an impact and control lug 23A on the upper surface of control member 18. On further leftward relative motion of star 12 coupled with clockwise rotary motion thereof, pin 15 is driven further downward while pin 13 slides along surface 23. In this way any serious vibration of star 13 is prevented by lug 23A, as it was previously presented by the walls of channel 21.

Control members 17 and 18 are of similar surface structure. In order to avoid useless repetitions, further relative motions will be discussed with reference to control member 17 and guide lug 25 upstanding from a left part of the upper surface thereof (FIG. and 6). (It will be understood similar motions occur along guide lug 24 in the left part of control member 18. It will also be understood that, when the control star left member 18, a further impact occurred on lug 23B of raised member 17, producing a further partial clockwise rotation as already described. The impact at 18 has brought pin into a position aligned with the circular center line D of guide groove 21, and in the relative motion of the control star the centered pin 15 then was preceded by pin 14 also aligned with this center line. The further impact at control member 17 imparted further clockwise rotation to the control star). Pins 13, 14 then are, respectively, in positions inside and outside guide lug 25, as shown in FIG. 6. Directly thereafter these pins reach guide groove 21A again, wherein they move in the same way that was shown in FIG. 3, except that they have been turned clockwise by 180.

If only one of control members 17, 18 had been raised, the star would have been turned 90. As already indicated, similar turning by one or two steps, but in counterclockwise direction, could be performed by raising one or two

outer control members

19, 20. Obviously the raising and lowering control for the control members, not shown herein, must be such that at no time inner and outer control members, for example 18, 20, are raised at the same time, since the mechanism would be broken by the impact ensuing in that case.

It will be understood that the forward or backward turning of control star 12 causes corresponding turning, preferably by fewer degrees, of drum 1 (FIG. 1). For this purpose, shaft 2 has a disk 3 secured thereto which has upstanding pins 4; these are so received in drum 1 as to make the drum rigid with the disk. The upper end of the drum has a disk 5, secured against rotation by a dowel 4A. Disk 5 is pressed downwards to press drum 1 against lower disk 3, by the bottom washer 6 of a compression spring 7, the upper end of which is retained by washer 8 on a coaxial top member 9 of shaft 2. Control star 12 has a shaft 12A which at its upper end carries pinion l0, meshing with larger gear 10A. That gear is inserted between disk 3 and drum 1, to rotate them as the gear is rotated by control star pinion 10. Both shafts 2 and 12A are pivoted in a supprt 5 (also shown in FIG. 3, but omitted in FIGS. 4-6). In order to avoid even the slightest, detrimental jolts of star 12, the shaft 12A is guided in a bearing B depending from support S (FIG. I).

It will be understood that, when the knitting machine has a number of pattern systems, each system can have a drum constructed in this same way. In this case each system of course has a control star 12, while a single annular groove 21 and a system of control members 17 to 20 sufi'lces.

The new mechanism turns pattern drums in steps of exactly such length as has been predetermined, even when relative motions of drum and control members are very rapid. Regardless of speed, the new mechanism operates without any objectionable jolt. Persons skilled in the art will appreciate that it, at the same time, is no more complex than the earlier machines for the same purpose.

What is claimed is:

1. Apparatus for the control of a pattern drum in a knitting machine, particularly in a large circular knitting machine, comprising: a control star for the drum, said star having two pairs of pins secured to the star and projecting from it; a substantially annular guide channel rotatable about its center, past the control star, and disposed to normally keep one pair of mutually opposite pins of said star in the channel and the other pair outside the same; and a control system on and rotatable with said guide channel for turning the star by a predetermined angle when the control system encounters a pin of the star.

2. Apparatus according to claim 1 wherein said guide channel is disposed to contact pins of said star, kept inside and one member outside the channel.

3. Apparatus according to claim 1 wherein said control system has at least one pair of control means, one for turning the star in one direction and the other for turning it in the opposite direction.-

4. Apparatus according to claim 3 wherein said control system has a second pair of control means, similar to the first pairs.

5. Apparatus according to claim 1 wherein said pins are uniformly spaced from one another.

6. Apparatus according to claim 3 wherein each control means has an impact surface for deflecting one of said pins and also has a guide surface for guiding, during at least part of said deflecting, another one of said pins.

7. Apparatus according to claim 6 wherein said impact and guide surfaces have such curvature as to slide along the respective pins, incident to the pin motions produced by relative motions of the star and the control system.

8. Apparatus according to claim 7 wherein each control means also has guide means for guiding a pin of the impact-deflected star back into said channel.

9. Apparatus according to claim 1 wherein said guide channel has a short gap adjacent said control system,

to provide space for turning said star.

i l i

Claims

3. Apparatus according to claim 1 wherein said control system has at least one pair of control means, one for turning the star in one direction and the other for turning it in the opposite direction.

9. Apparatus according to claim 1 wherein said guide channel has a short gap adjacent said control system, to provide space for turning said star.