US2964971A

US2964971A - Variable drive apparatus

Info

Publication number: US2964971A
Application number: US588153A
Authority: US
Inventors: Blydenburgh Walter
Original assignee: RCA Corp
Current assignee: RCA Corp
Priority date: 1956-05-29
Filing date: 1956-05-29
Publication date: 1960-12-20
Anticipated expiration: 1977-12-20

Description

Dec. 20, 1960 w. BLYDENBURGH 2,964,971

VARIABLE DRIVE APPARATUS Filed May 29, 1956 3 Sheets-Sheet. 1

INVENTOR. WHLTER BLYDENBUREH Dec. 20, 1960 Y w. BLYDENBURGH' 2,964,971

VARIABLE DRIVE: APPARATUS Filed May 29, 1956 5 Sheets-Sheet 2 x HE 1 m .NY-'HAHA w lIIlllllllllmlllllllllllllll 3 HII R :sul E s Alun vx o h AE I IN V EN TOR.

A WFM-EP BLYDENBLIREH Wr/m M Dec. 20, 1960 w. BLYDENBURGH 2,954,971

VARIABLE DRIVE APPARATUS Filed May 29, 1956 3 Sheets-Sheet 5 INVENTOR. WF1 crap: BLYDENEUREH MMM /q ORNE Y States Pte VARIABLE DRIVE APPARATUS Filed May 29, 1956, Ser. No. 588,153

17 Claims. (Cl. 74-567) This invention relates to Variable drive apparatus. The invention has for one of its objects the provision of a novel mechanical ararngement wherein the thrust of one drive member, against a second drive member, is modified in response to the position of the one member in relation to the second drive member, and wherein the second member exerts the modifying iniluence. While not limited thereto, the invention is herein described as embodied in lapparatus for winding wire-like material on spools, and incorporating a novel cam follower arrangement according to the invention.

The foregoing and related objects are achieved in an embodiment of the invention incorporating a mechanical assembly comprising Va cam, ya cam follower engaging the cam, and means includingvthe cam follower for varying the displacement of said cam. As herein described, the cam and cam follower arrangement cooperate to provide, in the winding apparatus, `a wire winding drive which is readily adjustable to accommodate spools of different widths.

Fig. l is a partially cut-away side view of winding apparatus according to the invention;

Fig. 2 is a side view of the apparatus shown in Fig. l, but in a different operating position;

Fig. 3 is a sectional view taken 'through line 3 3 of Fig. l; andy Fig. 4 is an illustration of lan adjustable Wedge cam according to another aspect of the invention.

In the manufacture of certain wire-like materials, such as grid-Wire for electron tubes, the wire is usually wound on commercially ava-ilable spools. These spools have relatively high dimensional tolerances, the widths of spools of a single spool type varying between relatively large limits. This variation in spool width is often of the order of several times the diameter of the wire to be wound. In such a case it is necessary to adjust the width of the winding on as pool so that it will neither exceed the width of the spool nor fall short of the spool end and create a gap at the end. (When the wire falls into such gap, caused by an incomplete winding on an extra wide spool, the wire layers become tangled, resulting in kinks or a breakage of the Wire when it is drawn from the spool.) At the same time it is desirable that the winding apparatus be capable of adjustment, to accommodate spools of different Widths, with a minimum of time and effort on the part of lan operator who positions the spool on its spindle. The problems Iaforementioned are `solved in the apparatus to be described.

Fig. l illustrates winding apparatus of the invention as embodied in la Wire spooling machine of the type adapted to wind relatively fine wire on a spool 12. The machine comprises a frame in the form of a base 14 having at one end thereof (-at the right side of Fig. l) a bracket 16 which supports a wire guiding reel 18. The other end of the base 14 is provided with a second bracket 20 in the upper end of which is journaled a shaft 22 to be described. Finally, there is fixed to the base 14 three 2,964,971 liatteritedA Dec. 210, 1960 rice 2

guide wheels

24, 26, and 28 for supporting and guiding a winding mechanism 30 to be described.

The winding mechanism As shown in Figs. l, 2, and 3, the winding mechanism 30 comprises another frame in the form of a housing 32 having a pair of tracks 3'4 and 36. The first track rolls on one guide Wheel 28 and the other track 36 rollsY on two

guide wheels

24 and 26. 'The mechanism 30 is consequently adapted to move in the directions indicated by arrow A in Fig. 1.

The housing 32 has a pair of

collars

38 and 40 in which are journaled the shaft 22 aforementioned. The

shaft 22 is provided with a number of flange-like collars 46 remains xed inglooatio-n with respect to the base 14.-

To assure that the pulley 46 remains xed with respect to the base 14, the pulley `46 is maintained within two arms 5l) and 52 of the second bracket 20 by means o f bearings 5'4 and 56. The pulley 46, and thus the shaft 22, is rotated by means of a belt 58 connected to a motor 60.

One end of the shaft 2.2 (the right end in Figs. 11 and 2) is adapted to support the spool 12 in a snug t thereon and thusY serves as a spool spindle. The spool 12 is xed to the shaft 22, as by a nut 62, to assure that the spool will rotate with the shaft. When the shaft 22 is rotated, say in direction B, Wire 10 from a wire source 64 is fed past the Wire guiding reel 18A and is wound on the spool 12.

In order to wind the wire 10 evenly along the spool 12, the spool 12 is reciprocated in -directions A to an extent equal to the distance between the flanges 66 and 68 of the spool 12. This reciprocation will now be described.

As shown in Figs. l and 3, the winding mechanism 30 has fixed thereto a first drive member in the form of a cardioid cam 70, the cam being mounted .on acam shaft 72' which is in turn journaled into the housing 32. The cam 70 bears against a second drive member in the form of a cam follower 74 which is maintained substantially xed with respect to the base 14. Actually, however, and 'as will be `described more fully in the following, the cam follower 74 is mounted for small arcuate movements in directions D to supplement the movement of the cam 70 so as to increase the range of movementA afforded by the engagement of `the cam with the cam follower.

The cam 70 is geared to the shaft 22 so that the shaft 22 makes a predetermined number of rotations'during each rotation of the cam 70. The gearing is shown here. in the form of a worm 76 and meshing worm gear 78.'

While a single worm drive has been shown for simplicity any equivalent gear box arrangement may be used to provide a readily changeable gear ratio between the shaft and the cam. The worm gear '78 and the cam 70 are each fixed to the cam shaft 72 so that the two rotate in unison with the cam shaft 72. Since the worm' gear 78 meshes with the worm 76, the cam 70 will rotate once to provide a back and forth movement in directions A every time the worm 76, and thus the shaft 22, makes a predetermined number of rotations. If, for example, the worm 76 is of the single lead variety,-and the worm gear 718 is providedwith sixteen teeth, the cam 70` would make `one rotation through an arc of 360 degrees for every sixteen rotations of the shaft 22. In such a case when the shaft 22 makes sixteen 360 degree rotations it is desirable that two layers of wire be-wound on, the

spool, one layer of eight turns during the back movement and one layer of eight turns during the forth movement. In this situation the wire to be wound would have a diameter approximately equalto 1/s of the distance between the two spool tlanges y66 and 68. In actual practice, however, the wire diameter may be of the order of one or two thousandths of an inch. This means that the ratio between the number of rotations of the camv 70 and the shaft 22 `should be a few thousand to one.- In such a case an equivalent gear box reduction unit would be used instead of the worm and worm gear combination illustrated for simplicity.

In operation, the shaft 22is rotated by the motor 60. This causes wire 10 to be wound on the spool 12. At the same time, the cam 70 rotates in direction C. The rotation of the cam 70 moves the winding mechanism 30 in a direction to the right (Figs. 1 and 2) causing the wire 10 to be Wound along the length of the spool core 80 (that is, along the width of the portion of the spool between the flanges 66 and 68).

Fig. 2 illustrates the position of the winding mechanism 30 when it has' reached the end of its travel in the direction to the right. It will be noted that the point 82 of the cam 70 is now in engagement with the cam follower 74. As the cam 70 continues to rotate in direction C, the winding mechanism 30 is moved in an opposite direction, namely in a direction toward the left, by means of aspring 84 which is connected between a portion of the housing 32 and a portion of the base 14.

The variable drive As has been mentioned before, the actual width of a spool is often different from its nominal width. The variable drive arrangement ofthe invention allows the Winding apparatus to be accommodated to differences in spool widths. The throw of the cam 70 is chosen to be equal to less than the minimum distance, between the `flanges 66 and 68, which is expected to be encountered in any of the spools 12 to be wound. Thus, for example, if the average width of the spool winding is three inches (the distance between spool flanges 66 and 68 being this distance), and the maximum variation in spool width is expected to be plus or minus 1A inch, then the initial throw of the cam 70 is adjusted to be not greater than 2% inches. The additional movement of the winding mechanism 30 will be made up by a movement of the cam follower 74 in direction D so as to provide, with the movement ofthe cam follower 74, a combined cam throw equal to the distance between the two anges 66 and 68 of the spool 12.to be wound.

The cam follower 74 is mounted for rotation about a shaft 86. The shaft 86, in turn, is fixed to an L-shaped arm `88 which is supported for rotation about a pivot 90 fixed with respect to the base 14. The position of the arm 88 with respect to the pivot 90 thus controls the position of the cam follower 74.

The position of the arm 88, and thus the initial position of the cam follower 74, is determined by the following: A first adjusting screw 92, which is threaded through a portion of the arm 88 remote from the pivot 90, extends through the arm 88 and contacts a plate 94. The plate 94 is xed to and extends from` the base 14. The iirst adjusting screw 92 is provided with a knob 96 for ease of adjustment. Since the spring '84 provides a pressure urging the cam 70 against the cam follower 7 4, the lower end of the iirst adjusting screw 92 is maintained in contact against a surface of the plate 94. The iirst adjusting screw 92, by an appropriate setting of the screw in the arm 88, controls the maximum travel of the winding mechanism 30 in one direction, the direction tothe left. This position of maximum travel is used to determine the right end (in Figs. I1 and 2) of the wire winding on the spool core 80. In practice, when ya spool 12 is mountedon the spool holding end of the shaft 22, the cam 70 is moved to its position of least throw (in the position illustrated in Fig. 1) and the lirst adjusting screw 92 is adjusted so that the end of the spool core adjacent to the right flange 68 is in alignment with the wire guiding reel 18. Thus, by an appropriate setting of the knob 96 of the screw 92, the starting position of the winding operation may be easily adjusted.

A second adjustment of the throw of the cam 70 is also provided. The second adjustment controls the end position of the camv throw. This second adjustment is used to determine the left end (Fig. 2) of the wire winding on the spool core 80. To permit of this adjustment the arm 88 is provided with a second adjusting screw 98 having a control knob 100. This second adjusting screw 98 is threaded into another portion of the arm 88 remote from the pivot 90. The second adjusting screw 98 bears against a lever 102 which is also supported for rotation about pivot 90. In order to maintain the lever 102 in contact with the screw 98 a spring 104 is connected at one end to a portion of the arm y88 adjacent to the second screw 98 and at the other end thereof to aportion of the lever 102 adjacent to the screw bearing surface thereof. A second cam follower 106 is lixed to the end ofthe lever 102 remote from the pivot 90. The second camfollower 106 is adapted to engage a wedge cam 108 tixedto the'base 14. When the second cam follower 106 engages the wedge cam 108 the second cam follower is given a motion or displacement toward the first cam follower 74 (a clockwise motion in one direction D); This motion is transmitted to the second screw 98, by means of the lever 102, and moves the arm 88 clockwise in the aforementioned one direction D so that the first cam follower 74 applies a force resulting in motion of the cardioid cam 70.

From the'foregoing it is seen that an appropriate setting of the rst knob 96 controls the maximum throw of the cardioid cam 70 in one direction (the direction to the right) and determines the position of the reel 18 with respect to the spool 12 at the start of the winding opera tion; and thefsecond knob controls the throw of the cam 70 in the opposite direction (the direction to the left) anddetermines the position of the reel with respect to the spool 12 when the wire 10 reaches the first spool flange 66.

The sequence of steps in adjusting the

knobs

96 and 100 will now be explained. An empty spool 12 is mounted on the end of the shaft 22 and the cam 70 is rotated to its position of least throw,A as illustrated in Fig. l. The first knob 96 is then rotated until the starting end of the spool 12 (the end of the spool adjacent to the ange 68) is in line with the wire guiding reel 18. The wire is then xed to the core 80 of the spool 12 as by being threaded through an aperture 110 in the spool 12 and the wire winding operation is started. When the winding mechanism 30 has moved the spool 12 to a position where the wire guiding reel 18 is adjacent to the other flange 66 of the spool 12, the second knob 100 is rotated to determine the maximum thrust of the cam '70 (Fig. 2). When these two adjustments have been made, namely the adjustment of

knobs

96 and 100, the wire winding operation is continued until the spool 12 is full. All of the layers of wire on the spool will have their position at the end adjacent to one ange 68 determined by the setting of one knob 96 and at the end of the winding adjacent to the other llange 66 determined by the setting of the other knob 100.

In the winding apparatus of Figs. l to 3 the wedge cam 108, which contributes to the control over the motion of the first cam follower 74, has been described as fixed to the lower track 36 of the housing 32. It will be appreciated that the steepness of the slope of the wedge cam 108 may itself be adjustable so as to give even ner control over the motion of the first cam follower 74 against the cardioid cam 70. Fig. 4 illustrates one such adjustable wedge cam 112 useful in the winding apparatus of Figs. 1 to 3. The wedge cam 112 is hinged, as by a hinge 114,

to the lower track 36 for movement in directions E. The slope of the cam 112 is determined by the setting of Aa thumb screw 1-16 which is threaded through a portion of the lower track 36 under the cam and bears against a sur-v face of the cam 112 facing the track.

From the foregoing it is seen that the variable drive apparatus of the invention contributes to a wire winding machine which is readily adaptable to wire spools of different widths and which accommodates these different spools with a minimum of time and effort on the part of an Operator.

While useful in the winding apparatus described, it is apparent that the variable drive apparatus is also useful in other mechanisms having a pair of drive members which cooperate to provide a single resultant motion and where it is desirable to have the movement of one drive member, against the other member, modified in response to the position of the one member with respect to the other member.

What is claimed is:

1. A motion transfer device including a cam, mounted for rectilinear and rotational movement a part to be moved, said cam engaging said part for movement therewith, a cam follower engaging said cam, said cam having a riser portion, said riser portion engaging said follower during a portion of a cycle of rotation of said cam and producing a displacement of the thicker portion of said cam in the direction of said follower, and rectilinear motion of said cam in a direction opposite to said first named direction and means connected to said cam follower for imparting to said follower a component of motion in a` direction opposite the direction of displacement of said cam in response to a portiononly of the rectilinear movement of said cam, said follower having a component of motion in said direction in response to another portion of the rectilinear movement of said cam, the magnitude of said displacement of said cam being fixed and means for adjusting the magnitude of movement of said cam follower, whereby said part to be moved is given a cumulative motion including the displacement of said cam and the movement of said cam follower during said another portion of the rectilinear movement of said cam.

2. Motion imparting means comprising a cam, a cam shaft for said cam, and a cam follower engaging said cam, a support for said cam, said'support being movable with respect to said cam follower, means for urging said cam into engagement with said cam follower for transmitting motion from said cam to said cam` follower, said cam being movable in a linear direction and means for moving said follower in said direction in response to a movement of said cam in said direction.

3. Motion imparting means comprising two members, a support for one of said members, said support being movable with respect to the other of said members, said one of said members comprising a cam and a cam shaft for said cam, said other of said members comprising a cam follower engaging said cam, means urging said members into engagement for transmitting motion from said one of said members to said other of said members, said one of said members being movable in a linear direction, and means for moving said other of said members in said direction in response to a movement of said one member in said direction.

4. A mechanical assembly comprising a cam, a cam follower engaging said cam, a cam shaft for said cam, said shaft responding in rectilinear movement in a given direction away from said cam follower in response to rotation of said cam, and a support for said follower, said support being movable in said direction and in response to said movement for modifying the magnitude of said movement in said direction.

5. A mechanical assembly comprising two spaced cams, and a cam follower between said cams, said cam follower being adapted to engage one of said cams, and power transfer means connecting said follower with the other of said cams', said cams having a structure for imparting displacements having components in substantially opposite directions, said power transfer means being mounted for transferring the displacement of the other of said cams to said one ofr said cams in response to the move'- ment of said one of said cams for modifying the displacement of said one of said cams. Y

` 6. Variable'drive apparatus comprising a cam mounted for rotation about an axis and for substantially rectilinear movement in a given direction, and a cam follower mounted in cam follower contact against said cam and for cam driving movementin said direction',r whereby the end motion of said cam in said direction is determined by the contour of said cam and by the motionrof said follower in said direction, said cam follower being adjustable to provide a predetermined magnitude of cam driving movement, whereby said end motionk of said cam is through a predetermined distance.

- 7. Variable drive apparatus comprisingfirst and second frames mounted for substantially rectilinear motion with respect to each other, a cam mounted on said first:

frame for rotation about an axis fixed with respect to said first frame, a cam follower movably mounted on said second frame and in cam follower relation with said carn, said cam follower being movable in a predetermined direction in response to rectilinear movement of said cam in said direction, whereby the movement of said frames with respect to each otheris determined by the contour of said cam and by the movement of said cam follower in said direction.

8. Variable drive apparatus comprising first and second frames mounted for substantially linear motion in a given direction with respect to each other, a cam mounted on said first frame for rotation about an axis fixed with respect to said first frame, a cam follower mounted on said second frame in motion transfer relation with `said cam and adjustable for movement in said direction, a' second cam mounted on said second frame and having a varying dimension in a direction substantially vopposite to said given direction, a second cam follower ymounted between said cams and adapted to engage said second cam in motion transfer relation therewith, and a motion transfer arm connecting said cam followers for transferring the'` movement of said second cam to said firstcam in responsel to the movement of said frames with' respect to =each other, whereby the movement of said frames with respect to each other is determined by thevc'ontourof said camy and by the position of said cam follower in saiddirection; 9. Wire winding apparatus comprising first and second frames mounted for linear rnotion with respectrto each other, a spindle mounted on said first frame for linear movement therewith and for rotation about an axis fixed with respect to said first frame and adapted to support a spool, a substantially cardioid cam mounted on said first frame for rotation about a second axis fixed with respect to said first frame and connected to said spindle for linear motion therewith, a wedge cam fixed to said second frame and having a motion imparting dimension substantially opposite that of said cardioid cam, a motion transfer structure pivoted on an axis fixed with respect to said second frame, a first cam follower mounted on said structure and engaging said cardioid cam in power transfer relation therewith, and a second cam follower mounted on said structure and engageable with said wedge cam for imparting movement to said first cam follower substantially opposite that of said cardioid cam, said wedge cam and first and second cam followers being positioned to move said first cam follower in a direction opposite said motion imparting dimension of said cardioid cam in response to the position of said spindle with respect to said second frame, whereby the linear movement of said spindle is determined by the lineal motion of said cardioid cam and the movement of said first cam follower.

l0. A driving mechanism comprising a first driving member, a first means connected to said first driving member for driving the same, a second driving member, and a second means connected to said second driving member for driving the same, said first and second driving members being in driving relation for transmitting motion from said second driving member to said first driving-member, said second means being actuated by saidfirst driving member.

11; A motion imparting mechanism comprising a frame, a wedge shaped cam mounted for movement with respect to said frame in one direction and having anvinclined surface for imparting movement in another direction, a lever assembly movable with respect to said cam and adapted to engage a part having an axisiixed with respect to said cam, said part being adapted to be moved by said cam, said assembly including a motion transfer structure having a cam fol-lower engageable with said surface to receive movement from said cam and to trans' mit said movement to said part to be moved in a direction substantially opposite said one direction, whereby said part to be moved is subjected to a movement by said cam supplementing the movement of said part in said one direction.

12. A motion imparting mechanism comprising a structure including a fixed support, an L-shaped lever having two arms, a rectilinear lever, one end of said rectilinear lever and one end of one of said arms being pivotally mounted on said support for rotation on a common axis, said L-shaped lever'having a junction portion of said arms adapted to engage a part to be moved in a rectilinear direction, a cam follower mounted on the other end of said rectilinear lever, means adjustably fixed to the other arm of said L-shaped lever and engaging said fixed support at the end of a rotational movement of said L-shaped lever in one direction for stopping said movement, means adjustably fixed to said other arm of said L-shaped lever and engaging said rectilinear lever, a cam movable with said part to be moved and engaging said cam follower during movement of said part, said cam having a riser portion for moving said cam follower to rotate said rectilinear lever in a direction opposite said one direction during movement of said part in said rectilinear direction, whereby said L-shaped lever is rotated in said opposite direction for supplementing the movement of said part in said rectilinear direction.

13. A mechanical assembly comprising first and second spaced cams, a cam shaft for said rst cam, a first cam follower engaging said rst cam and a second cam follower engaging said second cam, a movable support and. a xed support, said cam followers being mounted in spaced relation on said movable support, said movable provide a predetermined modification of movement of.

saidcam shaft.

l5. A mechanical assembly according to claim 13,V and wherein said first cam is heart shaped, and said second cam is wedge shaped.

16. A variable drive apparatus comprising a movable support, a shaft mounted on said support, means restraining longitudinal movement of said shaft with respect to said support, a cam shaft mounted on said support and extending normal to said shaft, a cam fixed eccentrically to said cam shaft, gears interconnecting said shaft and cam shaft, whereby rotation of said shaft causes rotation of said cam shaft and cam, a camk follower engaging said cam, a second support for said cam follower, and means for moving said second support in a direction axially of said rst named shaft when said movable support is moved in said direction.

17. A Variable drive apparatus according to claim 16 and wherein said means for moving said second support includes a wedge shaped cam fixed to said movable support, a cam follower spaced from said rst named cam follower and engaging said wedge shaped cam, and a lever system supporting said cam followers and mounted on a xed pivot in a plane intermediate said cam followers.

References Cited in the tile of this patent UNITED STATES PATENTS Y 1,199,105 Nuttall Sept. 26, 1916 1,592,060 Wilcox July 13, 1926 2,224,905 Franz Dec. 17, 1940 2,301,642 Roddy Nov. 10, 1942 2,533,094 Cooper Dec. 5, 1950 2,574,775 Belcher Nov. 13, 1951 2,678,394 Curtis May 11, 1954 2,759,367 Doutt Aug. 21, 1956 V2,771,250 Icenbice Nov. 20, 1956 FOREIGN PATENTS 542,689 Germany Jan. 30, 1932