US3186242A

US3186242A - Driving mechanism of circular knitting machines

Info

Publication number: US3186242A
Application number: US229455A
Authority: US
Inventors: Frederick E Deans; Carlyle H Wainwright
Original assignee: Bentley Engineering Co Ltd
Current assignee: Bentley Engineering Co Ltd
Priority date: 1961-10-11
Filing date: 1962-10-09
Publication date: 1965-06-01
Anticipated expiration: 1982-06-01
Also published as: GB1040021A; DE1291845B

Description

F. E. DEANS ETAL June 1, 1965 DRIVING MECHANISM OF CIRCULAR KNITTING MACHINES Filed Oct. 9, 1962 5 Sheets-Sheet 1 PK: Imam-ens:

FREnERscK Exam DEANS AND CQRLYLE l-kaasrz'r MEIQRT Amway June 1, 1965 F. E. DEANS ETAL 3,185,242

DRIVING MECHANISM OF CIRCULAR KNITTING MACHINES Filed Oct. .9, 1962 5 Sheets-Sheet 2 ATTORNEY June 1965 F. E. DEANS ETAL 3,185,242

DRIVING MECHANISM OF CIRCULAR KNITTING MACHINES Filed 001;. 9, 1 962 5 Sheets-Sheet s \NVENToRs; FREDER\Q\ unman DEANS PHD Q'PRLYLE 5355GT wmem ATPKERNEY June 1, 1965 F. E. DEANS ETAL DRIVING MECHANISM OF CIRCULA R KNITTING MACHINES Filed Oct. 9, 1962 5 Sfieets-Sheet 4 (mam-0 5 FREDEFUQK Emma bar-w: m1) (g Enema-r @mduaewr I m 6 mm mufi-m m .m a 3: m E f m a AFPPQRN Y June 1, 1965 F. E. DEANS ETAL 3,186,242

DRIVING MECHANISM OF CIRCULAR KNITTING MACHINES Filed Oct. 9, 1962 5 Sheets-Sheet 5 United States Patent Thisinvention is for improvements in or relating to driving mechanism of circular knitting machines and has for one of its objects to provide a driving mechanism'by which reciprocatory knitting motion as well as continuous rotary knitting motion can be effected in a reliable and efficient manner.

In the operation of circular knitting machines for producing hose and of certain other machines for producing patterned fabric, the knitting motion is required to be performed sometimes as a continuous rotary motion and at other times as a reciprocatory or oscillatory motion with alternating swings in opposite directions, as for example in knitting heel and toe pouches. It is usual in forming heel and toe pouches of hose for relative oscillation to be caused to take place between the needle cylinder and the cam box in such manner that knitting will take place on one group of needles usually extending around approximately one half of the needle circle, while the remaining needles hold their loops. Such reciprocatory knitting is necessarily slow compared with continuous rotary knitting and imposes a substantial limitation on the' rate of overall output of a machine. The change from rotary movement to oscillating movement is normally effected by means of a clutch interposed in the drive of-the cylinder or cam box enabling the drive to be taken alternatively from a shaft which is driven continuously in the same direction or from a rack and pinion drive usually provided by an oscillating gear or quadrant engaging a driven pinion. The oscillating gear is caused to move to and fro continuously during the operation of the machine and the usual manner of driving it is by a crank and connecting rod. This manner of driving a quadrant does not permit attainment of thehighest possible efiiciency because it is inherent in a crank motion that the movement transmitted through, the connecting rod only attains maximum speed for a very short proportion of the cycle, the remaining portions of the quadrant movement being occupied by periods of acceleration and deceleration.

Attempts have been made to shorten the periods of acceleration and deceleration and at the same time shorten the duration of the stroke of the oscillating gear and provide a longer period of movement at the fastest speed, by employment of a disc cam suitably shaped to provide the required speed changes in oscillatory movement. Such attempts have not, however, up to the present time, resulted in producing a form of construction which is completely satisfactory in practice. In the earlier constructions an undesirable feature is present which is found to hamper increase of speed of oscillatory knitting, namely that the drive transmitting members operate to apply the driving force to the oscillating gear out of alignment with the latter with creation of a tendency for rocking of parts transversely in relation to their plane of motion. The invention seeks to provide an improved form of drive 'whereby the foregoing disadvantages are overcome and an increase in speeds of reciprocatory knitting can be secured.

In accordance with the invention. there is provided, a circular knitting machine, driving meansfor performing reciprocatory knitting comprising an oscillatory gear, two complementary cams for oscillating said gear, and cam 3,136,242 Patented June 1, 1965 followers co-operating respectively with said cams and coupled to the oscillatory gear at positions which are in balanced arrangement in relation to the central plane of the oscillatory gear. The two complementary cams have their cam tracks so formed as to provide the required short periods of acceleration and deceleration with a lengthened period of maximum speed movement between them and to operate the oscillating gear in its opposite directions of movement respectively. In the preferred form the cams are edge cams. k

In a convenient form of the improved driving mechanism the oscillatory gear or quadrant is of hollow form With sides spaced apart in the direction along its pivotal FIGURE 1 is a perspective View from the rear, showing part of the'driving mechanism of a circular knitting machine,with certain parts broken away;

FIGURE 2 is a back view of part of the frame of the machine showing in detail an oscillatory quadrant and its mating pinion and the quadrant cams carried on the main cam shaft of the machine;

FIGURE 3 is a cross sectional view showing the quadrant and quadrant cams and cam followers taken on the line III-III of FIGURE 2;

FIGURE 4 is a view showing in detail the means for adjusting one of the followers to remove play;

FIGURE 5 is a view showing a means for timing the quadrant cams with respect to the cam shaft gear in order to obtain alignment of the clutch dogs;

FIGURE 5 is a side elevation view of the parts shown in FIGURE 5; and

FIGURE 7 shows graphically the rate of travel of a cam driven quadrant as in comparison with the rate of travel of a crank driven quadrant.

FIGURE 1 shows the driving gearing for use on a circular knitting machine having a rotary needle cylinder or two rotary co-axial needle cylinders. The needle cylinder, or each needle cylinder, is gear driven from a vertical shaft which in turnis driven by a bevel gear 8 carried on a horizontal shaft 9 which is mounted in bearings in the walls of a frame 4 (FIG. 2).

Freely mounted on the shaft are two pinions 1t) and 11 each of which has clutch dogs respectively shown at 12 and 13 formed on one face, with such dogs projecting towards one another; Between the two pinions is mounted a clutch body 7 having

dogs

14 and 15 formed on oppositely directed end faces. The clutch body is mounted on splines formed locally on the shaft so that it can be slid along the shaft to engage either of the clutch dogs of the pinions thus coupling the shaft to one or the other of the pinions 10, 11.

FIGURES l and 2 show the clutch body 7 in engagement with the pinion 11 which is meshed with pinion 16 (FIG. 1) fixed to a lay shaft 17. Lay shaft 17 (shown broken in FIG. 1) is driven .by any one of three

speed change gears

18, 19 or'Zil which mate respectively with three gears 21, 22. and 23 mounted on a pulley shaft 24.

by a pulley which is itself driven through a friction clutch from the main power supply. It may be mentioned here that the friction clutch takes the place of the idle pulley commonly used in this type of machine.

The foregoing description explains how rotary motion is imparted to the needle cylinder cylinders and also describes the clutch arrangement. In order to change to oscillating motion of the needle cylinders the clutch body must be shipped to disengage dogs from dogs 13 of the pinion 11 (FIG. 2) and bring dogs 14 of the clutch body 7 into engagement with dogs 12 of the pinion 10. The latter is driven first in one direction and then in the other by a quadrant 29 which is caused to oscillate with shaft 30 on which it is mounted. The quadrant 29 is driven constantly (even during rotary knitting) in a manner which will be described later.

With the clutch in engagement with the quadrant pinion 10 the shaft 9 is now changed from rotary motion to oscillating motion and this motion is transmitted through bevel pinion 8 to the needle cylinder or cylinders.

The drive to the quadrant will now be described. As can be seen in FIGURES 1, 2 and 3 the quadrant 29 is of open construction allowing it to straddle a cam shaft 31. It is firmly secured to the shaft 30, the ends of which are located in bearings in the walls of a frame 4. This construction, by spacing the two bearings far apart, ensures a minimum of play in the quadrant. There are two

cams

32 and 33 and these are fixed together and secured to revolve with the shaft 31. Secured to the quadrant are two spindles carrying respectively cam followers 34- and 35 which follow the peripheries of cams 3?. and 33 respectively. The cams are so designed that they are complementary to one another, i.e., in making a complete revolution therollers are both always maintained in contact with their respective cams. By referring to FIGURE 3 it will be seen that with the cams being driven in a clockwise direction cam followers 34 will be moved in a counter clockwise direction by the slope 32a of the cam 32 thus driving the quadrant 29 in a counterclockwise direction about the axis of the shaft 30. A counterclockwise movement of the quadrant will continue until the peak of the cam 32 is past the followers 34 and then the cam 33 will take over the drive, the slope 33a moving the follower 35 and the quadrant in a clockwise direction. I

Cam follower 35 is adjustable as shown in detail in FIGURE 4 so that any discrepancies in manufacture of the various components which could result in play between the cams and followers can be counteracted. The spindle of follower 35 is provided with fiats which locate in a slotted hole in the quadrant and a screw 44 is positioned to bear onto the spindle to adjust its position in the slot. Screw 44 is adjusted until the follower 35 is contacting cam 33 while the follower 34 is also in contact with cam 32. The nut 45 on the spindle is then tightened to lock the spindle to the quadrant (FIG. 3).

The cam shaft 31 has a spline formed locally, upon which a gear 3? is mounted and this gear is driven through an intermediate gear by a gear which is fixed to the lay shaft 17. As explained earlier the lay shaft 17 is driven through the three speed change gears and is revolving constantly whether the cylinders are rotating or oscillating.

It will be appreciated that in order to ship the clutch to change from rotation to oscillation it is necessary that the dogs of the clutch body 7 be in alignment with the dogs of the quadrant pinion 19 when the change is made. As the clutch body 7 and the quadrant 29 are revolving at different speeds the timing of the disengagement from the one set of dogs and engagement with the other set must be very precise. The quadrant pinion 10 is assembled in mesh with the quadrant teeth and with the clutch dogs of the pinion in the correct position to receive the dogs of the clutch body at the moment of shipping the clutch. This positioning is only accurate however, to a tooth pitch and in order to obtain finer adjustment the quadrant earns 32 and 33 are provided with means by which they may be adjusted angularly with respect to the gear 39 which drives the cam shaft. This will now be described with reference to FIGURES 5 and 6.

The

cams

32 and 33 are located with respect to one another by means of a stud or pin 36 the said cams being locked together between the shoulder of the stud and the nut 3'7, with a spacer 38 between them. The shaft 31 is shouldered and the cam assembly is pushed up to this shoulder. The end of shaft 31 is splined to be driven by the gear 39 which is mounted adjacent to the cam assembly. Gear 39 has a block 40 fixed to it in a position where it straddles the stud 36 protruding from the cams. The block carries two

screws

41 and 42 which contact the stud 36 on opposite sides and by adjusting these screws the cams may be rotated to a limited extent with respect to the gear. This will have the effect of altering the position of the quadrant teeth with respect to the gear teeth, thus altering the angular position of the quadrant pinion 10 with respect to the pinion 11 so that upon disengagement of the clutch body from pinion 11, pinion 10 can be positioned correctly to be engaged by the clutch as it is moved across.

Having timed the cams with respect to the gears the cams and gear 39 are clamped up to the shoulder of the shaft 31 by the nut and washer 43, through the inner race of a bearing in the wall of the frame 4 (FIG. 2). FIG- URE 2 also shows a cam 44 used for other purposes, which may be plined to the shaft and locked between the inner race and the nut washer 43.

It can be seen from the drawings, particularly in FIG- URE 2, that the illustrated construction provides aquadrant and quadrant drive mechanism which is compact, with the forces contained in the plane of motion, the cams and followers being located within the side walls of the quadrant body. The improved efiiciency obtained from this form of construction with suitably designed cams can readily be seen in comparison with that of a quadrant driven by a crank through a connecting rod, by reference to FIG. 7. In this figure the horizontal scale indicates of turning movement of the cam or crank and the vertical scale shows the rates of travel of quadrants driven by the two methods. Line B denotes the rate of travel by the crank method and line A by the cam method, with the crank and cam shafts revolving at the same speed, It can readily be seen that the stroke of the crank driven quadrant is composed nearly entirely of acceleration and deceleration, the peak speed being maintained for only an instant, whereas the speed of the cam driven quadrant is maintained at a maximum for the majority of the stroke. It is obvious that the maximum speed of the cam driven quadrant may be increased to the peak speed of the crank driven quadrant by increasing the speed of the cam shaft, thus increasing the speed of the knitting cycle when knitting by oscillation, and reducing the time taken to produce a pouch by oscillatory knitting.

What we claim is:

1. A driving mechanism for performing reciprocatory knitting on circular knitting machines comprising an oscillatory gear of hollow form, a shaft on which said oscillatory gear is mounted, a rotatable cam shaft disposed through the hollow form of said oscillatory gear, two complementary cams for oscillating the oscillatory gear in opposite directions mounted thereon within the hollow form, two cam followers cooperative with their respective cams coupled to said oscillatory gear, mounting means supporting the shafts of said oscillatory gear and cams, a first pinion in mesh with said oscillatory gear having a clutch dog on one face, a supported shaft passing through said pinion and clutch dog, a bevel gear attached to one end of said shaft, 21 second pinion attached to the other end of said shaft and having a clutch dog on one face, a clutch body disposed between said clutch dogs on said shaft and movable to engage one of said clutch dogs, speed change gears, a supported lay shaft on which said speed change gears are mounted, a third pinion mounted on said lay shaft in mesh with said second pinion, drive means connected to said speed change gears, whereby rotary knitting motion is changed to oscillatory knitting motion by disengaging said clutch body from the clutch dog on said second pinion and moving it into engagement with the clutch dog on said first pinion.

2. A driving mechanism according to claim 1 wherein said cam followers are at balanced positions in relation to the central plane of said oscillatory gear, and further wherein the two complementary cams have their cam track-s formed to provide short periods of acceleration and deceleration with a longer period of maximum speed movement between said short periods, and are mounted to operate the oscillatory gear in its opposite directions of movement respectively.

3. A driving mechanism according to claim 1 wherein the mounting means for said cam fol-lowers provides facility for accurate adjustment of the cams about the shaft for timing engagement of the clutch body with the clutch dogs on the two pinions.

4. A driving mechanism according to claim 3, wherein said mounting means includes a block formed with an elongated aperture, a stud engaging in the aperture in said block, adjusting screws for fixing the stud in adjusted position in the elongated aperture, and means connecting the block and stud one to the driving wheel and the other to the cams.

5. Driving mechanism according to claim 1 wherein the complementary cams are edge cams.

6. Driving mechanism according to claim 2 wherein the mounting for the follower for one of the cams is provided on one side of the oscillatory gear and the mounting for the follower of the other of the cams is provided on the other side of the oscillatory gear.

7. Driving mechanism according to claim 6 further comprising mounting means for one of the followers wherein it is adjustable on the oscillatory gear in a direction transversely of a line joining the follower to the pivotal axis of the oscillatory gear.

References Cited by the Examiner UNITED STATES PATENTS 651,828 6/00 Copland 7454 1,118,411 11/1'4 Gr-anz 7454 1,254,617 1/18 Montgomery 74125 2,103,825 12/37 Robertson 7490 X BROUGHTON G. DURHAM, Primary Examiner.

Claims

1. A DRIVING MECHANISM FOR PERFORMING RECIPROCATORY KNITTING ON CIRCULAR KNITTING MACHINES COMPRISING AN OSCILLATORY GEAR OF HOLLOW FORM, A SHAFT ON WHICH SAID OSCILLATORY GEAR IS MOUNTED, A ROTATABLE CAM SHAFT DISPOSED THROUGH THE HOLLOW FORM OF SAID OSCILLATORY GEAR, TWO COMPLEMENTARY CAMS FOR OSCILLATING THE OSCILLATORY GEAR IN OPPOSITE DIRECTIONS MOUNTED THEREON WITHIN THE HOLLOW FORM, TWO CAM FOLLOWERS COOPERATIVE WITH THEIR RESPECTIVE CAMS COUPLED TO SAID OSCILLATORY GEAR, MOUNTING MEANS SUPPORTING THE SHAFTS OF SAID OSCILLATORY GEAR AND CAMS, A FIRST PINION IN MESH WITH SAID OSCILLATORY GEAR HAVING A CLUTCH DOG ON ONE FACE, A SUPPORTED SHAFT PASSING THROUGH SAID PINION AND CLUTCH DOG, A BEVEL GEAR ATTACHED TO ONE END OF SAID SHAFT, A SECOND PINION ATTACHED TO THE OTHER END OF SAID SHAFT AND HAVING A CLUTCH DOG ON ONE FACE, A CLUTCH BODY DISPOSED BETWEEN SAID CLUTCH DOGS ON SAID SHAFT AND MOVABLE TO ENGAGE ONE OF SAID CLUTCH DOGS, SPEED CHANGE GEARS, A SUPPORTED LAY SHAFT ON WHICH SAID SPEED CHANGE GEARS ARE MOUNTED, A THIRD PINION MOUNTED ON SAID LAY SHAFT IN MESH WITH SAID SECOND PINION, DRIVE MEANS CONNECTED TO SAID SPEED CHANGE GEARS, WHEREBY ROTARY KNITTING MOTION IS CHANGED TO OSCILLATORY KNITTING MOTION BY DISENGAGING SAID CLUTCH BODY FROM THE CLUTCH DOG ON SAID SECOND PINION AND MOVING IT INTO ENGAGEMENT WITH THE CLUTCH DOG ON SAID FIRST PINION.