US2667771A - Straight knitting machine and method of operating the same - Google Patents

Description

Feb. 2, 1954 J. vAcLAvfi STRAIGHT KNITTING MACHINE AND METHOD OF OPERATING THE SAME 3 Sheets-Sheet 1 Filed Sept. 25, 1948 INVENTOR: 7

Feb. 2, 1954 J. vAcLAvlk STRAIGHT KNITTING MACHINE AND METHOD OF QPERATING THE SAME Filed Sept. 25, 1948 '3 Sheets-Sheet 2 fi u. -HL

n H H w H. H .n. n-

Feb. 2, 1954 J. vAcLAvl'K STRAIGHT KNITTING MACHINE AND METHOD OF OPERATING THE SAME 5 Sheets-Sheet 3 Filed Sept. 25, 1948 INVENTOR.

HTTORNEYS.

Patented Feb. 2, 1954 STRAIGHT KNITTTNG MACHINE AND METHOD OF OPERATING THE SAME Jaroslav Vaclavik, Zlin, Czechoslovakia, assignor to Bata, narodni podnik,'Zlin, Czechoslovakia Application September 23,1948, Serial No. 50,794

Claims priority, application Czechoslovakia December 12,, 1947 14 Claims.

The present invention relates to straight knitting machines, with draw-off or welt rods housed in magazines, and more particularly to a method and an apparatus for inserting the draw-oii or welt rods into. the'knitted fabric manufactured on straight knitting machines.

The methods hitherto known for inserting the welt or draw-01f rods are automatic in part only, and moreover are relatively complicated and require careful assistance. The assistant has to bring each of the welt rods, during the'operation of the machine, by hand to a preparatory position, from whichthe rod is removed, either by hand or automatically, and placed in front of the hooks oi the draw-01f device.

More recently an arrangement for inserting the welt rods has been proposed which represents an improvement overthe prior arrangements in that instead of placing each welt rod by hand in preparatory position, a set of welt rods are introduced at a time into magazines which are located on either side of the needle bank above the combs for the picot edge. From the magazines, the individual welt rods are advanced by a special device first to a preparatory position, 1. e. into special holders fastened directly on the picot edge combs. During the knitting of a part, of the double welt of a stocking the assistant moves by hand the picot edge comb to its operative position, .i. .e. above the knitting needles, whereby also the holders with theindividual welt rods are transferred from their preparatory position to a position in front of the hooks of the draw-off belts. By a vertical idle stroke of the narrowing device, and thus also of the picot edge combs, in the direction towards the knitting needles and by the back stroke .to inactive position, i. e. away from the knitting needles, the endsv of the welt rods are taken automatically out. of the holders by the hooks of the draw-off device and are ,drawn away from the needles by the knitted fabric.

This method of inserting the rods requires, in

. addition to the manualoperations, a special device for transferring the individual rods from the' magazines to the auxiliary holders on the picot edge combs, and further requires turning them by hand from the preparatory position and then imparting, lateral movement to the maincam [shaft with verticalmovement oithe whole of the idle movement in a downward direction of 2 the picot edge combs,-the narrowing needles are caused to come incontact between the slnkers with the knitting needles and with the meshes hung on the same, causing the meshes to be tensioned without transferring them sidewise. The construction of the machine as a whole becomes complicated, apart from the greater effort of the assistants and responsibility required from them.

If the assistants have a plurality of machines with a small number of needle banks entrusted to their care, the knitting operations of the individual machine are not synchronous, so that it is necessary to put in operation by hand the picot edge combs and thus introduce the welt rods at different moments, whereby particular care is required on the part of the assistant since by failing to put in operation the picot edge combs and with them the welt rods, ware of lower quality may be produced.

The invention disclosed hereinafter permits to eliminate the above mentioned disadvantages, and consists substantially in causing the welt rods, which have been introduced at any desired time into a magazine, to occupy successively and quite automatically their working position in front on the hooks of the draw-off device. Thereby the assistants work is considerably simplified since theassistant, who needs not be particularly skilled, merely has to pull out the rods from the finished ware and to introduce them again in the magazines at any desired time. In addition the'output of the machines is increased and a larger number of machines may be entrusted to a single assistant, thereby shown at the moment when the draw-01f or welt rods are in inoperative position and the knitted fabric is being drawnaway directly by the hooks of the draw-off device;

Fig. 2 is a detail view corresponding to Fig. 1, but showing the welt rods in their working position, the lowermost rod having been withdrawn from the magazine by the hooks of the draw-off device;

Fig, 3 is a view similar to Fig. 2, but the remaining welt rods are shown again out of their working position, the lowermost rod together with the knitted fabric being pulled away by the hooks of the draw-off device;

Fig. 4' shows the apparatus in elevation as viewed in the direction of the arrow S shown in Fig. 1, and the magazine in section along the line 44 of Fig. 1, with the welt rods in their inoperative position;

Fig. 5 is a detail view of a part of Fig. 4 and shows at a larger scale the right hand magazine in inoperative position with the chamber opened, and the feeding device;

Fig. 6 is a cross-sectional view of the magazineand the chamber along the line 66 of Fig. 4;

Fig. 7 is an axonometric view of the driving device for the apparatus; and

Fig. 8 is a detail view at a larger scale showing the switching or change-over lever.

The apparatus shown for carrying out the method of the invention is mounted on a straight knitting machine of which only the knitting needles I, the cooperating sinkers 2, the knitted fabric 3, and the draw-ofi hooks 4 of a comb 5 are shown in Figs. 1 to 3. The comb is moved by means of a roller 6 and a spring I connected at its both ends to the said comb 5, as may be seen in Fig. 1. In the working table 8 there is mounted a transverse shaft 9 provided with a holder III on either side of the needle bank, the holders I having chambers I I fastened thereon, as is shown also in Figs. 4 and '7. Magazines I2 may be displaced within said chambers under the action of a feeding device, as shown in Fig. 5. To make the access more easy, each chamber is provided with a lid I4, as shown in Fig. 4. Each magazine I2 is provided with a groove I3, as is shown more clearly in Fig. 6, for guiding the ends of the draw-off or welt rods I which are in contact with each other by means of their spacing rings I 6 so as to leave a. gap II of suflicient size between adjacent rods, as may be seen in Fig. 5. The lowermost rod bears with its ends against the bottom of the groove I3 on the magazine I2. The number of the superposed welt rods I 5 depends on the size of the magazine and may be chosen according to requirements in any particular case. In another groove I8 provided in the magazine I2 opposite to the longitudinal groove I3, as is shown in Fig. 5, a locking member 20 is mounted on a fulcrum I9, a pin 2I provided on the locking member being guided in a groove 22 of the chamber II, as is shown in Fig. 4. .The free end of the locking member 20 is formed as a nose 23 (Fig. 5) which under the pressure of a fiat spring 24 fastened to the magazine, engages for a time into the gap ll between the end of the lowermost draw-off rod and the end of the adjacent rod.

The feeding device for advancing the magazines and their welt or draw-01f rods I5 from the inactive position A to the working position B (Figs. 4 and 5), and in reverse direction, comprises a small single arm lever 25 mounted for rocking movement on a fulcrum 26 in the chamber II. A flat spring 21, fastened with its one end to the inner wall of the chamber II, exerts pressure by its free end on the single arm lever 25, as is shown also in Fig. 6. The free rounded end 28 of the lever 25 engages in a recess 29 formed in the magazine I 2, as is shown more particularly in Fig. 5; the lever 25 is provided with a longitudinal groove 30 to receive a driving pin 3I secured to the end of a link 32 mounted movably in the chamber II. The opposite end of the link 32 is guided in a groove provided in a small single arm lever 33 by means of a pin 34, as is shown in Figures 1, 4 and 7. The small lever 33 is fastened on a shaft 35 which is mounted loosely in holders 36 secured to t transverse shaft 9 adjacent to the side members 31, as is shown more particularly in Figs. 4 and '7.

One end of the shaft 35 has fastened thereon a small holder 38 provided with a pin on which one end of a tension spring 39 is secured, the other end of the spring being held by a hanger 49 fastened in the holder 36. A pin 4I screwed into the end face of the transverse shaft 9 carries rotatably a single arm switching or changeover lever 42, as is shown also in Fig. 8, the free end of the lever being formed as a nose 43. In the arm of the lever 42 there is mounted a pin 44 with a head 45 for securing a steel strip 45 which connects the head 45 with the holder 38. Adjustment of the pin 44, and thus of the steel strip 46, is made possible by two nuts 41 on the other end of the pin 44. The hub of the change-over lever 42 is provided in a portion of its periphery with two teeth 48 and 49, and a pawl 50 (Fig. 7) mounted rotatably on a pin 5| screwed in the wall of the holder 36 is adapted to engage alternately with the said teeth 48 and 49. The latter are located in unequal distances from the center of the hub of the lever 42, the tooth 48 being spaced a smaller distance from the center of the hub. The pawl 50 is held against the tooth 48 or 49 by a torsion spring 52 secured to a pin 53 on the holder 36, as is shown in Figures 7 and 8. The arm 54 of the pawl 59 is adapted to be subjected for a time to the action of the bent end 55 of a releasing link 56 which is fastened adjustably by means of screws 5! on a single arm lever 58. In the end of the lever 58, which is fastened on a shaft 59, there is mounted rotatably a pin provided with a head 60 having a notch 6I formed therein to serve as a guideway for a thin rod 62 held firmly in a holder 63. The latter is fastened on the one end of a pin 64 which is mounted rotatably in a small bracket 65 and whose other end has secured thereon a pusher 66 which at a certain time acts upon the nose 43 of the'change-over lever 42. The bracket 65 is fastened on a reciprocating slide 61 of the sinker device of the knitting machine, as is shown also in Fig. 1. The sinker mechanism employed is described in detail in the co-pending application, Ser. No. 25,606, filed May 7, 1948, now U. S. Patent 2,571,314, issued October 16, 1951, and is not further illustrated here since its details are not necessary to an understanding of the present invention.

An impulse for the operation of the apparatus in accordance with the present invention is transmitted at the suitable moment from a pattern drum 63 (Figs. 1, 4 and 7) which is rotatably mounted in the side member 31 and has on its periphery a series of cam projections of different heights and lengths, of which a low projection 69 or a high projection ID, for instance, co-operates at a definite time with a small lever II mounted for rocking movement about a fulcrum which is not shown. A link I2 connected with the lever II has its other end connected to a single arm lever 13 which is fastened to a shaft 59 mounted for free rotation in the side members 31.

Of the set of welt or draw-off rods I5 which are in the working position B shown in Fig. l, the ends of the lowermost rods resting on the knitted fabric? cooperate with the respective hooks I4 (asg is shown also in Fig. 2) of the belts I5 of thedraw-ofl device which belts have both their ends fixed to a bar I6 (Fig. 7) connecting the hooks I4. The draw-off belts 15 are guided over rollers TI (Fig. l) freely rotatable on holders 18,

which are fastened on. the working, table ll. The winding and unwinding. of the draw-off. belts I5 is efiected by the draw-off roller It? and the discs 8.0.

The apparatus as far described operates. in the following manner:

During the tim of knitting the first half of the double welt of a stocking, when the apparatus in accordance with the present invention has. not yet been put in operation, as. is shown in Fig- 1, the knitted fabric is held by the hooks. t and is pulled away by the comb 5 which is being moved by means of the rollers 6 and springs l in. the corresponding guideway in a direction away from theneedles I.

At this stage the. pattern drum. t3 occupiesv just the position. in which the lever H rests on a low cam projection 59 (Figs. 1 and '7), so that the pusher 66 carried along by the reciprocating slide 8? does not abut against. the nose 13 of the change-over lever 52, and moves without obstruction' in the recess of the lever 4-2. as is shown in Fig. 4. In the position of the pattern drum 88 the bent end 55 (Fig. '7) of the releasing link 55 is held out of contact with the arm 5d of the pawl 58, and the latter, being urged by the torsion spring 52, engages with the tooth which is spaced a smaller distance from the center of the hub of lever 42.

In the position. shown in 'Z the change-over lever 42 through the intermediary of the tensioned steel strip 46, the holder 38, the shaft 35, the lever 33, the link 32 and the lever 25, keeps the magazine I 2 with the set of welt rods located in the latter in the inoperative position A (Figs. 45 and 5). The hooks I l of the draw-ofi belts 15 at this stage also occupy their inoperative position between the needles I and the welt rods it, as is shown in 1.

When. the picot edge been completed, or during the following period of knitting the second half of the double Welt of a stocking, the apparatus described will be brought in operation by the effect of the pattern drum tit, which is driven by the main cam shaft (not shown). of the pattern drum 68 in the direction of the rrow in Figures 1 and 7, the lever l! slips down from a low cam projection 63 on to the periphery of the drum 68. The link '62 connected to the lever 'Ii' is moved downwards causes the lever 73, the shaft 553 and the lever 58- to turn downwards through a certain angle. Due to the angular movement of the lever the 68 together with the rod 62 guided in the slot 5i (as is shown also in 4:) are moved down. As a consequence the holder 83 and pin 6d are caused to turn, thereby deflecting the arm of the pusher 66 away from th nose :3 of the change-over lever 42, as shown in dotted lines in Fig. l. By the rocking movement of the lever 56 the releasing link 55 is moved down. and the. bent end. 55 of the same comes to bear against the arm 54 of the pawl 5!! which becomes disengaged from the tooth d8 of the lever 52. Under the action of the steel. strip 46 and the tension spring 39, the holder is caused. to turn downwards and the lever #22 rotates toward. the holder 35 till the tooth 45% of the lever i2 is brought in engagement with the pawl 5t. By the downward rotation of the holder 3-8 andv thus of the shaft. 35 with the lever 33, the link 32 is pulled out of the chamber II (Fig. 1). By engagement of the driving pin 3! of the link 3'2 in the longitudinal groove 39 of the lever 25 and under the pressure of the flat spring-2.7.- on the said lever 25, th latter is caused to rock down By rotation about the pin 26 (Fig. 5). The magazine I2, being entrained. by the rounded end 28' of the lever 25 together with. the set of welt rods I5 located in the magazine, is advanced from the inactive position A to the working position B, as is shown also in Fig; 5. During this movement of the. magazinel2, the pin. of the locking lever 29 carried along with the magazine slides in th corresponding groove 22' (Fig. 4'') of the chamber ll, whereby th nose 23' of the lever 25 under the. pressure of the flat spring 24. engages in the gap IT... 1. e.. between the end I4 of the lowermost welt rod. I5 and that of the adjacent: welt rod, as is. shown in liig.v 52.

The tooth 23 of' the locking lever 20 separates the lowermost weltrod I5 from the adjacent rod and maintains the rest of the welt rods in the working position 3' (Fig. 2). The lowermost rod bearing with its ends against the bottom of the groove. [.3 in. the. magazine I2 is in the working p.osition.B,.i. e.. in front of the hooks- 4 of the comb 5. in the position. shown in dotted lines in Fig. 1. On. the main. draw-ofi. operation being automatically initiated, i. eby rotationof the draw-off roller '19 in the direction. of the. arrow in Fig. 1, the draw-off belts. I5 are wound up and the hooks 1-4 are moved. towards the draw-off roller 59; The withdrawn hooks l4 seize automatically the lowermost rodv l5 and pull. it,. while still guided in the grooves of th magazines, away from the needles I until the rod leaves the magazines (Fig. 2). The rod. thus held by the hook I4 draws off the fabric 3 until the stocking. is completely knitted. The comb: 5 remains stationary and the leading end of the knitted fabric 3, which. end ishung'on the hooks. 4 or the comb 5. iscaused to slide by the tension of the rod [5 along the stems of the hooks 4 towards the comb. 5' where the said end bears against the backsof the hooks, as is shown in Fig. 3.

Since the set. of welt rod's I5 occupying the working position B would hinder th automatic hanging over of the double welt, i.. e. the free passage of the comb 5 with the leading row of meshes towards the needles 5, the remaining rods must be moved to the inoperative position A, where they shouldv remain until the next insertion step, that is till. the welt of the next stocking will have to be knitted.

When the lowermost rod I5 has been pulled out of the magazine I2, the apparatus in accordance. with the present invention is again operated by the step by step rotation of the pattern drum 68. The lever 7| which rests on the periphery of the drum 68 encounters a high projection Ill whereby the link I2 is moved up and the lever I3, the shaft 59 and the lever 53 are rotated upwards (Figures 1, l and 7). Owing to the lever. 58 being rocked, the head 60 is moved up together with the r0d' 62 guided in the slot 61,-. Turning, of the holder 63 and pin 64 takes place, thereby deflecting the arm of the pusher 6G in the. direction towards-the nose of the lever 42. Due to the movement of the slide iii of the sinker device towards the commanding drum b3, the arm of the pusher 68 comes to bear against the nose 43 of the change-over lever 42 causing the latter to turn in the direction to the pattern drum 68 till the tooth 48 of the lever engages again with the pawl 50; The steel strip it; carried. along with the lever"'42-'is tensioned and causes. the holder 38", the shaft 35 and the lever 33 to be rotated upwards, so that the link 32 enters the chamber H. By the link 32 being introduced into the chamber II' the lever 25 is caused to rock up about the pin 26 to its original bers H, the pin 2| of the locking lever 20 slides in the corresponding groove 22 of the chamber H, thereby causing the nose 23 of the locking lever 20 to be moved against the pressure of the fiat spring 24 from within the gap I! to its original position (Fig. The set of welt rods l5, which until now has been held by the nose 23 of the locking lever in the magazine l2 (Fig. 2), falls to the bottom of the groove I3 of the magazine l2 whereby the rods are in a position ready for further automatic insertion (Fig. 3). The magazines 12, which are gradually emptied during the operation of the knitting machine, are refilled when required by introducing a number of rods at a time. The further step by step rotation of the pattern drum 68 will cause the lever TI to slip from a high cam projection It again on a low projection 69 where it will remain up to the moment when the rods will have to be inserted again in the knitted fabric.

When the second half of the welt has been completed, the comb 5 is moved automatically under the action of the usual mechanism for hanging over the double welt, together with the leading end of the knitted fabric 3, towards the needles I and hangs over the first row of meshes on the knitting needles I. The type of device for automatically hanging over the double welt, with which the machine is equipped, is of no importance for the present invention, and it is also immaterial whether the draw-01f combs are arranged in a lying position or in the direction of the axes of the knitting needles.

What I claim is:

1. In a method of inserting the draw-off rods for the double welts of stockings to be knitted on a straight knitting machine having sets of drawolf rods contained in magazines and take-up devices operable to engage draw-off rods in the magazines, which comprises advancing the magazines to position the, lowermost draw-oi rods therein in the path of the take-up devices and effecting the transfer of the lowermost draw-off rods from the magazines to the welt of the knitted fabric in a fully automatic manner in timed relation with the operation of the knitting machine.

2. In a method of inserting the draw-off rods for the double welts of stockings to be knitted on a straight knitting machine having sets of drawoii rods contained in magazines and take-up devices operable to engage draw-off rods in the magazines, which comprises advancing the magazines to position the lowermost draw-off rods therein in the path of the take-up devices and effecting the transfer of the lowermost drawoff rods fromithe magazines to the welt of the knitted fabric in a fully automatic manner in timed relation with the operation of the knitting machine and controlling by the movement of the sinker mechanism of the knitting machine the transfer of the magazines with the draw-off rods from their inoperative position to their operative position and vice versa.

3. In a method of inserting the draw-01f rods for the double welts of stockings to be knitted on a straight knitting machine having sets of drawofl rods contained in magazines and take-up devices operable to engage draw-off rods inthe magazines, which comprises advancing the magazines to position the lowermost draw-off rods therein in the path of the take-up devices and effecting the transfer of the lowermost draw-off rods from the magazines to the welt of the knitted fabric in a fully automatic manner in timed relation with the operation of the knitting machine by a feeding device and a changeover device connected to the latter and adapted to co-operate with a pusher device fastened on the reciprocating slide of the sinker mechanism of the knitting machine and operated by a pattern drum.

4. In a straight knitting machine, an apparatus for inserting the draw-off rods for the double welts of stockings in theprocess of manufacturing the latter, the apparatus comprising magazines, sets of draw-off rods in the magazines, means for transferring the magazines between inoperative and operative positions, means which during the transfer of the magazines with the draw-off rods from the inoperative into operative positions, are adapted to separate the lowermost draw-01f rod of each set from the remaining draw-off rods of that set, and take-up devices, adapted to engage and remove the lowermost draw-01f rod from each magazine upon movement of the latter into operative position. 7

5. In a straight knitting machine, an apparatus for inserting the draw-ofl rods for the double welts of stockings in the process of manufacturing the latter, the apparatus comprising magazines, sets of draw-off rods in the magazines, means for transferring the magazines between inoperative and operative positions, means which during the transfer of the magazines with the draW-ofi rods from the inoperative into operative position are adapted to separate the lowermost draw-off rod of each set from the remaining draw-01f rods of that set, take-up devices adapted to engage and remove the lowermost draw-off rod from each magazine upon movement of the latter to operative position, and means which during the return movement of the magazines from the operative to inoperative position are adapted to cause the remainder of each of the set of draw-off. rods to fall on to the bottoms of the magazines.

6. In a straight knitting machine, an apparatus for inserting the draw-off rods for the double welts of stocking in the process of manufacturing the latter, the apparatus comprising magazines, sets of draw-ofi rods in the magazines, shifting means for transferring the magazines between inoperative and operative positions, means which during the transfer of the magazines with the draw-oif rods from the inoperative into operative position are adapted to seperate the lowermost draw-ofi rod of each set from the remaining draw-off rods of that set comprising locking means carried along with the magazines and adapted to engage for a time between the ends of the bottom two draw-off rods of each set and retain each set of rods above the lowermost one thereof from moving down in the magazine, take-up devices, adapted to engage and remove the lowermost draw-off rod fromeach magazine upon movement of the latter to operative position. means which during the return movement of the magazines from the operative to inoperative position are adapted to release the locking means to cause the remainder of each of the set of draw-01f rods to fall on to the bottoms of the magazines, and means for nun controlling the operation of each of the looking means carried along with the corresponding magazine.

'7. i he apparatus as set forth in claim 6, which further includes chambers within which said magazines are displaced, and wherein the means for controlling operation of each of said looking means is comprised of a profiled groove in a chamber and a pin on said locking means slidable in said groove.

8. In a straight knitting machine, an apparatus for inserting the draw-off rods for the double weits of stockings in the process of manufacturing the latter, the apparatus comprising magazines, sets of draw-off rods in the magazines, shifting means for transferring the magazines between inoperative and operative positions, means which during the transfer of the magazines with the draw-off rods from the inoperative into operative position are adapted to separate the lowermost draw-off rod of each set from the remaining draw-off rods of that set comprising locking means carried along with the magazines and adapted to engage for a time between the ends of the bottom two draw-oil rods of each set and retain each set of rods above the lowermost one thereof from moving down in the magazine, take-up devices adapted to engage and remove the lowermost draw-off rod from each magazine upon movement of the latter to operative position, means which during the return movement of the magazine from the operative into inoperative position are adapted to release the locking means to cause the remainder of each of the set of draw-on? rods to fall on to the bottoms of the magazines, means for controlling the operation of each of the locking means carried along with the corresponding magazine, and chambers in which the magazines with the sets of draw-01f rods in the same are guided and which are arranged on both sides of the needle banks of the knitting machine adjacent to the knitted fabric.

9. The apparatus as set forth in claim 8, in which a shifting device for transferring the magazines with the draw-off rods is mounted on each chamber, a changeover device is provided and links connect the changeover device with the shifting devices.

10. The apparatus as set forth in claim 9, in which the shifting device comprises a single arm locking lever mounted on the said chamber and having its free end in engagement with a recess 10 in the said magazine, and the connection with the link comprises a groove in the said lever in engagement with a driving pin on the said link.

11. The apparatus as set forth in claim 10, in which said change-over device comprises a rocking change-over lever connected with the link of the shifting device and having a hub provided with two teeth at different spacings from its center, a pawl adapted to engage alternately with the said teeth, said lever provided at its end with a nose, and a pusher device adapted to bear at times against said nose to rock said lever.

12. The apparatus as set forth in claim 11, in which the said pawl by engagement with the teeth of the said change-over lever, which the said pusher device is adapted to deflect at a suitable moment, serves to secure the changeover lever in positions corresponding to the inoperative and operative positions of the magazines for the draw-off rods.

13. The apparatus as set forth in claim 12, in which said pusher device comprises a bracket fastened upon the reciprocating slide of the sinker device of the knitting machine, a pin rotatable about its axis carried by said bracket, a pusher element adapted to bear against the nose of said change-over lever, a holder, said pusher element and holder being mounted rigidly on said pin for rotation about the pin axis, and a rod fastened rigidly to said holder, said rod being disposed laterally of said pin and being movable to rotate said holder and pusher element so as to alternatively clear or bear against said nose.

14. The apparatus as set forth in claim 13 and which further includes a pattern drum having cam projections of different height thereon is provided and in which the cam projections control the rotative position of said pusher element with respect to the nose of the change-over lever so that the pusher element clears the nose when the magazine is to be moved to operative position and engages the nose to actuate the lever to return the magazine to inoperative position after insertion of a draw-oil rod.

JAROSLAV VACLAVI K.

References Cited in the file of this patent UNITED STATES PATENTS Number

Images