US3482068A

US3482068A - Combined switch device and centrifugally operable actuator therefor

Info

Publication number: US3482068A
Application number: US674789A
Authority: US
Inventors: Everett P Larsh
Original assignee: Hobart Corp
Current assignee: Whirlpool Corp
Priority date: 1967-10-12
Filing date: 1967-10-12
Publication date: 1969-12-02
Anticipated expiration: 1986-12-02

Description

Dec. 2. 1969 E P. LAR'SH 3,482,068

COMBINED SWITCH DEVI CE AND CENTRIFUGALLY OPERABLE ACTUATOR THEREFOR Filed Oct. 12, 1967 5 Sheets-Sheet 1 INVENTOR EVERETT P. LARSH "mm fla 1 ATTORNEY Dec. 2. 1969 p LARSH 3,482,068

COMBINED SWITCH DEVICE AND CENTRIFUGALLY OPERABLE ACTUATOR THEREFOR Filed 12, 1967 Sheets-Sheet 2 60 I oa 48 oa Ill 6 lllll INVENTOR EVERETT P. LARSH "mm %M A TTO/PNE' Y 3,482,068 BLE Dec. 2. 1969 E. P. LARSH COMBINED SWITCH DEVICE AND CENTRIFUGALLY OPERA ACTUATOR THEREFOR 3 Sheets-Sheet 5 Filed Oct. 12, 1967 R V: M %M N R Wm m T W fiA P. T T E R Wm 9 w G Y a m m 4 H United States Patent US. Cl. 200-80 14 Claims ABSTRACT OF THE DISCLOSURE The combination of an electric switch device and a centrifugally operable actuator therefor. The switch and actuator unit is particularly adapted for use with an electric motor which is provided with a starting winding or the like. The switch and the actuator therefor are combined as a unit for mounting within a frame or end bell of an electric motor or the like.

BACKGROUND OF THE INVENTION The subject matter of this application constitutes an improvement over the structure disclosed in my Patents No. 3,058,355, No. 3,194,078, and No. 3,293,398.

It is customary in some types of electric motors to provide a starting winding which is used only in the starting of the motor. In the starting of the motor, after the rate of rotation of the motor rotor reaches a given value, means are provided for de-energization of the starting winding. In the past, the means for de-energization has usually included a switch device which has been mounted in the motor frame or end bell of the motor and an actuator device which has been mounted on the shaft of the rotor. It is necessary to mount the switch device and the actuator device in precise relative positions in order to obtain accuracy in operation of the switch.

However, it has been found very difficult and/or time consuming to secure the switch device to the housing or end bell and to secure the actuator device to the shaft so that the switch is operated at a desired predetermined rate of rotation of the shaft. For example, unless the switch device and the actuator device are mounted very carefully in desired relative positions, the switch may be operated by the actuator device at a rate of rotation of the shaft which is less than or greater than the rate of rotation which is desired for operation of the switch. Such improper operation of the switch is, of course, objectionable or undesirable.

Another condition which adds to the problem involved in the mounting of such devices is that a motor shaft is usually supported in a manner to permit limited axial movement thereof. Therefore, if an actuator device is secured to the shaft, the actuator device moves axially with axial movement of the shaft. Such axial movement of the actuator device may result in movement thereof to a position with respect to the switch device so that the switch device is not operated when the predetermined rate of rotation of the shaft occurs.

Thus, it is an object of this invention to provide a combined switch and actuator unit in which the desired space relationship between the actuator and the switch is always maintained. Thus, maximum accuracy and precision of operation of the switch is maintained.

It is another object of this invention to provide such a switch and actuator unit which can be easily installed or mounted in operating position.

Other objects and advantages reside in the construction of the invention, combinations thereof, the method Patented Dec. 2, 1969 of manufacture, and the mode of operation, as will become more apparent from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is an exploded perspective view of a switch and actuator unit of this invention.

FIGURE 2 is an enlarged side sectional view, with parts broken away, of the switch and actuator unit of FIGURE 1. FIGURE 2 shows the elements of the unit in the normal positions thereof.

FIGURE 3 is an enlarged side sectional view, with parts broken away, similar to FIGURE 2, showing the elements of the unit in the actuated position thereof.

FIGURE 4 is a bottom elevational view, drawn on a smaller scale than FIGURES 2 and 3, showing the elements of the unit in the positions thereof shown in FIGURE 2.

FIGURE 5 is a bottom elevational view drawn on substantially the same scale as FIGURE 4 showing the elements of the unit in the positions thereof shown in FIGURE 3.

FIGURE 6 is a sectional view, taken substantially on line 66 of FIGURE 4.

FIGURE 7 is a perspective view of another switch and actuator unit of this invention.

FIGURE 8 is an enlarged side elevational view of the unit shown in FIGURE 7.

FIGURE 9 is a sectional view, taken substantially on line 99 of FIGURE 8.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A switch and actuator unit of this invention may be mounted within an end bell or housing of an electric motor. However, a unit of this invention may also be used with other apparatus and may be mounted at or in any suitable portion thereof. The unit shown in FIGURES 1-6 comprises an engagement member or connector member 10 which is adapted to be attached to a suitable support member 12. The support member 12 may be any stationary element, such as a portion of a motor housing or an end bell or the like, not shown.

The engagement member 10 is adapted to be positioned adjacent a rotary shaft 16. The shaft 16 is shown as having one or more keys or key portions 20. Each of the keys or key portions 20 is disposed within a key slot 24 of an inner sleeve or inner rotor 22 which encompasses the shaft 16. The inner rotor or sleeve 22 is freely axially movable wtih respect to the shaft 16 as each key 20 fits freely Within its respective slot 24.

The inner rotor or sleeve 22 is provided with an annular groove 28 which slidably receives an engagement portion 30 of the engagement member 10. Preferably, the engagement portion 30 has parts within the annular groove 28 at diametrically opposite portions of the rotor 22. The portion 30 is shown as being arcuate and extends around more than one-half the periphery of the inner rotor 22 so that the engagement member 10 is attached to the inner rotor 22 while permitting relative rotative movement therebetween. The portion 30 of the engagement member 10 may be slightly resilient. Thus, when the portion 30 is arcuate and extends around more than one-half the periphery of the rotor 22, the engagement member 10 may be connected to the rotor 22 by forced snap action or the like, as the portion 30 resiliently increases in dimension momentarily to receive the rotor 22.

A carrier member 36 encompasses the inner rotor 22 and is attached thereto by means of a collar 38 which is secured to a reduced diameter end portion 39 of the inner rotor 22. The carrier member 36 has a radially extending face portion 40 which terminates in a peripheral axially extending flange portion 42. At the juncture between the face portion 40 and the flange portion 42 is a plurality of protuberant pivot portions 44, shown in FIGURES 1-5 which may be provided in any suitable manner. Herein, the pivot portions 44 are formed by indentations in the face portion 40. The face portion 40 has a plurality of openings or windows 45 therein, each of which is adjacent one of the pivot portions 44.

Freely encompassing the inner rotor or sleeve 22 is an outer rotor or outer sleeve 46. The outer rotor or outer sleeve 46 has a radially extending engagement disc 48. Adjacent the disc 48, the outer rotor 46 has a plurality of spring seat portions 50. The spring seat portions 50 are disposed in pairs around the periphery of the outer rotor or sleeve 46. Intermediate each pair of spring seat portions 50, but spaced from the disc 48, is a protruding cam portion 52. Thus, there is a plurality of cam portions 52.

Each pair of spring seat portions 50 and the cam porton 52 disposed therebetween form a group of protuberances on the periphery of the outer sleevce 46, as shown in FIGURE 1. Each such group of

protuberances

50 and 52 is adjacent an opening 45 in the face portion 40 of the carrier member 36.

The outer sleeve or rotor 46 has an inwardly extending rim 56, shown in FIGURE 2, which is normally in engagement with a shoulder 58 of the inner sleeve or rotor 22, shown in FIGURES 1, 2, and 3.

A plurality of actuator members 60 is carried by the inner rotor 22 and by the outer rotor 46. Each actuator member 60 includes a weight portion 62, a base portion 64, and a lever portion 65. The weight portion 62 of each actuator member 60 is adapted to be disposed within one of the openings 45 of the face portion 40 of the carrier member 36. The lever portion 65 of each actuator member 60 is in engagement with one of the cam portions 52 of the outer rotor 46.

Each actuator member 60 also includes a resilient arm 68. The resilient arm 68 may consist of any suitable member such as one or more spring wire members. A central portion of each resilient arm 68 is firmly attached to a base portion 64. The resilient arm 68 has a V-shaped engagement portion 70, which extends therefrom as shown in FIGURE 1. The V-shaped portion 70 engagingly straddles one of the pivot portions 44 of the carrier member 36, as illustrated in FIGURES 2 and 3. Thus, the engagement portion 70 of each actuator member 60 is pivotal about one of the pivot portions 44.

The resilient arm 68 of each actuator member 60 is shown as having a pair of laterally extending loop portions 72 at opposed parts of the base 64. The opposite ends of each resilient arm 68 are seated in one of the pairs of spring seat portions 50. Thus, each resilient arm 68 is in compression and pivotal about a pair of the spring seat portions 50, as well as being pivotal about one of the pivot portions 44 of the carrier member 36, as shown in FIGURES 2 and 3. The actuator members 60 thus join the inner rotor 22 to the outer rotor 46 for rotation one with the other.

Each resilient arm 68 normally urges the outer rotor 46 and the inner rotor 22 in opposed axial directions. However, the inwardly extending rim 56 of the outer rotor 46 normally engages the shoulder 58 of the inner rotor 22 and limits the relative axial movement between the outer rotor 46 and the inner rotor 22, as shown in FIGURE 2.

A bracket member 80 is attached to the engagement member by any suitable means, such as by pins 82 shown in FIGURES l, 2, and 3. The bracket member 80 has a first end portion 80a and a second end portion 80b, as shown in FIGURE 1. The bracket member 80 supports an electrical switch mechanism 84 which extends between th end Por ions 8041 nd 89 Th sw ch m chanism 84 may be any suitable electrical switch mechanism but is preferably a switch mechanism made according to the invention disclosed in my Patent No. 3,293,398.

The switch mechanism 84 includesa resilient stem 90 which is attached to the end portion b of the bracket 80 and extends to a position adjacent the end portion 80b. A connection lug 89 is attached to the stem adjacent the end portion 80a of the bracket 80. The stem 90 has a contact carrier portion 90a which carries an electrical contact 91. The end portion 80b of the bracket 80 supports an electrical contact 92 adjacent the electrical contact 91. The electrical contact 91 is engageable with the electrical contact 92 with bending action of the stem 90. The contact 92 has attached thereto a connection lug 93.

The end portion 80b of the bracket 80 has an extending abutment member 94 which is engageable by the end of the stem 90 for limiting the bending movement thereof in a direction from the contact 92.

A U-shaped resilient leg 96 has a portion thereof attached to the stem 90. The resilent leg 96 has an end portion 96a engageable with a tab 98 which extends from the contact carrier portion 90a of the stem 90. The resilient leg 96 carries a pressure button 99 which is engageable by the disc 48 for bending movement of the resilient leg 96.

OPERATION The engagement member 10, with its portion 30 disposed within the annular groove 28 of the inner sleeve 22, retains the inner rotor 22 in a given position with respect to the support structure 12 and with respect to the switch mechanism 84.

When the shaft 16 is not rotating or is rotating at a rate less than a given rate, the elements of the apparatus are in the relative positions thereof shown in FIGURES 2 and 4. In such position, the resilient arms 68 force the outer rotor 46 toward the annular groove 28 of the inner sleeve 22, as shown in FIGURE 2. Such movement .of the outer rotor 46 with respect to the inner rotor 22 is limited by the shoulder 58 of the inner rotor 22 which is engaged by the inwardly extending rim 56 of the outer rotor 46.

Such position of the outer rotor 46 with respect to the switch mechanism 84 causes the disc 48 to engage the pressure button 99 which is carried by the resilient leg 96, as shown in FIGURES 2 and 4. Therefore, the resilient leg 96 is bent toward the stem 90, and the stem 90 is bent toward the bracket 80. Thus, the electrical contact 91 which is attached to the stem 90 is in engagement with the electrical contact 92, which is attached to the connection lug 93. Thus, an electrical circuit between the

lugs

89 and 93 is completed with engagement of the electrical contact 91 with the electrical contact 92, as shown in FIGURE 4.

After rotary operation of the shaft 16 begins, the rate of rotation thereof rapidly increases. The inner rotor 22 which is attached to the shaft 16 by means of the keys 20 and the key slots 24 rotates with the shaft 16. The engagement portion 30 of the engagement member 10 which is disposed within the annular groove 28 of the inner sleeve 22, retains the inner sleeve 22 against axial movement while permitting rotary movement thereof. Due to the fact that the shaft 16 is axially movable with respect to the inner rotor 22, any axial movement of the shaft 16 which may occur during starting and during operation of the rotor to which the shaft 16 is attached has no effect upon the operation of the apparatus. Thus, until the shaft 16 reaches a predetermined rate of rotation, the

electrical contacts

91 and 92 remain in firm engagement, one with the other, and maintain a circuit between the connection lugs 89 and 93.

As the rate of rotation of the shaft 16 increases, the rotational rate of the inner rotor 22 and the outer rotor 46 increase therewith. Therefore, as the rate of rotation of the shaft 16 increases, centrifugal forces upon the weight portions 62 of the actuator members 60 increase and the weight portions 62 of the actuator members 60 tend to move outwardly in a direction from the shaft 16. As the centrifugal forces upon each actuator member 60 increase, the weight portion 62 thereof tends to pivotally move about an axis established by the engagement of the V-shaped engagement portion 70 of the actuator member 60 with a pivot portion 44 of the carrier member 36.

As the rate of rotation of the shaft 16 and the

rotors

22 and 46 increases, a condition occurs in which the centrifugal forces acting upon the weight portions 62 overcome the resilient forces of the resilient arms 68. At the instant this condition occurs the weight portions 62 of the actuator members 60 move outwardly to a position as shown in FIGURES 3 and 5, as pivotal movement of each actuator member 60 about its respective pivot portion 44 occurs.

As shown and discussed, the loop portions 72 of each resilient arm 68 are seated in a pair of the seats 50 of the outer rotor 46. Therefore, as the actuator members 60 pivotally move, the resilient arms 68 thereof change in the general angle thereof from the slope thereof shown in FIGURE 2 to a position slightly inclined from a line normal to the axis of rotation of the shaft 16, as shown in FIGURE 3. With this change in angle of the resilient arm 68, there is a change in the direction of force of the resilient arms 68.

Due to the fact that the effective length dimension of each resilient arm 68 decreases only slightly as the angle thereof changes from that shown in FIGURES 2 and 4 to that shown in FIGURES 3 and 5, the total or effective resiliency of the resilient arms 68 increases only slightly as the change in angle thereof occurs. Therefore, the change in angle or the lever action of each resilient arm 68 in its movement from the position thereof shown in FIGURE 2 to the position thereof shown in FIGURE 3, as the resilent arm 68 is seated in a seat 50, urges the outer rotor 46 toward the carrier member 36.

However, the greatest force urging movement of the outer rotor 46 toward the carrier member 36 occurs from lever action of the actuator members 60. When the weight portion 62 of each actuator member 60 moves outwardly in a direction from the shaft 16, the base portion 64 and the lever portion 65 thereof move to the left as shown in FIGURE 3, as pivotal action occurs about the pivot portion 44. Such movement of the lever portion 65 causes the lever portion 65 to apply leverage action or force upon the cam portion 52 of the outer rotor 46. This leverage action or pressure urges the outer rotor 46 axially toward the carrier member 36. Thus, each actuator member 60 as it pivotally moves under centrifugal forces, applies a lever action or force upon the outer rotor 46 and urges the outer rotor 46 toward the carrier member 36.

Thus, there is relative axial movement between the outer rotor 46 and the inner rotor 22. Due to the fact that the inner rotor 22 is retained against axial movement by the engagement member 10, the outer rotor 46 moves axially toward the carrier member 36, while the axial position of the inner rotor 22 does not change.

When the outer rotor 46 moves toward the carrier member 36 of the inner rotor 22, the engagement disc 48 of the outer rotor 46 moves in a direction away from the electric switch mechanism 84. Thus, the engagement disc 48 moves out of engagement with the pressure button 99 which is carried by the resilient leg 96. Therefore, the upper portion of the stem 90 moves away from the bracket 80. Thus, the electric contact 91 carried by the stem 90 is separated from the electric contact 92 which is attached to the connection lug 93, as shown in FIG- URE 5. Thus, the circuit between the connection lug 89 and the connection lug 93 is opened. Thus, operation of the actuator mechanism opens any circuit within which the switch mechanism 84 is connected.

When the rate of rotation of the shaft 16 decreases below a given value, the centrifugal force upon the actuator members 60 decreases to such a value that the force of the resilient members 68 overcomes the centrifugal force upon the weight portions 62 and the actuator members 60 pivotally move from the positions thereof shown in FIGURES 3 and 5 to the positions thereof shown in FIGURES 2 and 4. Thus, the disc 48 of the outer rotor 46 moves into engagement with the pressure button 99 of the resilient leg 96 and moves the resilient leg 96 to the position thereof shown in FIGURE 4. Thus, the electrical contact 91 is again moved into engagement with the electrical contact 92.

Due to the fact that the inner rotor 22 and the shaft 16 are relatively axially movable, any axial movement of the shaft 16 during rotation thereof does not affect the position of the inner rotor 22 or the outer rotor 46 with respect to the switch mechanism 84. Therefore, any axial movement of the shaft 16 does not affect the operating conditions of the actuator members 60 and the disc 48 upon the switch mechanism 84. Furtherfore, the desired relative positions of the inner rotor 22, the outer rotor 46, and the switch mechanism 84 are fixed and are not affected by the location of the support structure 12 to which the engagement member 10 is attached. Thus, installation of the electric switch and actuator unit of this invention can be performed easily and readily.

APPARATUS OF FIGURES 7-9 The apparatus of FIGURES 79 is similar to that of FIGURES 16 except that an inner rotor 122 is secured to a shaft 116 for rotation therewith and for axial movement therewith. The inner rotor 122 has a carrier member 136, which is similar to the carrier member 36 of FIG- URES l-6, attached thereto.

The inner rotor 122 is provided with an annular groove 128 within which a portion of an engagement member or connector member is disposed. The engagement member 110 is similar to the engagement member 10 discussed above. The engagement member 110 has an axially extending stud 111 secured thereto and disposed within an opening 113 of fixedly positioned structure 112.

An outer rotor 146 encompasses the inner rotor 122 in a manner similar to that shown and discussed in regard to the inner rotor 22 and the outer rotor 46 of FIGURES 1-6. A plurality of actuator members are similar to the actuator members 60 of FIGURES l-6 and are joined to the

rotors

122 and 146 in the manner discussed above with respect to the

rotors

22 and 46 and the actuator members 60.

The actuator members 160 operate in a manner similar to that described with respect to the actuator members 60. Outward pivotal movement of the actuator members 160 causes relative axial movement between the outer rotor 146 and the inner rotor 122. The inner rotor 122, as stated above and as shown in FIGURES 7 and 9, is secured to the shaft 116. Thus, the outer rotor 146 moves axially upon the inner rotor 122 as the actuator members 160 pivotally move outwardly as a result of centrifugal forces applied thereto with rotative movement of the

rotors

122 and 146. The outer rotor 146 has an engagement disc 148 which, with axial m vement of the outer rotor 146, operates any suitable switch mechanism 184 which is carried by the engagement member 110. Connector lugs 189 and 193 are attached to the switch mechanism for electrical connection thereto. Any suitable flexible electrical conductor members may be attached to the connector lugs 189 and 193.

Due to the fact that the inner rotor 122 is secured to the shaft 116, the inner rotor 122 is axially movable with any axial movement of the shaft 116. Such axial movement of the shaft 116 causes axial movement of the engagement member 110 which has a portion thereof disposed within the annular groove 128 of the inner rotor 122. The stud 111 which is fixed to the engagement member 110 has guided axial movement within the opening 113 of the structure 112 with axial movement of the engagement member 110. Thus, any axial movement of the shaft 116 results in axial movement of the switch mechanism 184 as well as axial movement of the

rotors

122 and 146. Thus, any axial movement of the shaft 116 does not disturb the relationship between the outer rotor 146 and the switch mechanism 184 which is carried by the engagement member 110.

Preferably, the engagement member 110 encompasses slightly more than one-half the periphery of the inner rotor 122 so that the engagement member 110 is connected to the inner rotor 122, while permitting relative rotary movement between the inner rotor 122 and the engagement member 110.

Thus, the apparatus of this invention shown in FIG- URES 1-6 and in FIGURES 7-9 constitutes a unitary mechanism which includes switch means and centrifugally operable actuator means therefor.

Although the preferred embodiment of the device has been described, it will be understood that within the purview of this invention various changes may be made in the form, details, proportion and arrangement of parts, the combination thereof and mode of operation, which generally stated consist in a device capable of carrying out the objects set forth, as disclosed and defined in the appended claims.

The invention having thus been described, the following is claimed:

1. Control apparatus responsive to rotary movement of a rotary drive member, comprising:

an inner rotor, an outer rotor, the outer rotor being coaxial with the inner rotor and encompassing a portion of the inner rotor, the rotors being relatively axially movable,

means for joining one of the rotors to a rotary drive member for rotation therewith while permitting relative axial movement between the rotor and the rotary drive member,

a plurality of actuator members carried by the inner rotor and the outer rotor and joining the rotors one to the other, each actuator member including a weight portion, each actuator member including resilient means urging relative axial movement between the rotors in a direction of one rotor from the other rotor, centrifugal forces resulting from rotation of the rotors causing movement of the weight portions of the actuator members so that the actuator members urge relative axial movement of the rotor members in a direction of one rotor toward the other rotor,

support structure engaging one of the rotors and limiting axial movement thereof while permitting rotary movement thereof,

switch mechanism carried by the support structure,

operator means carried by the rotor which is not engaged by the support structure, the operator means being engageable with the switch mechanism and movable with respect thereto for operation thereof.

2. The apparatus of claim 1 in which the support structure encompasses a portion of the said rotor which is engaged by the support structure so that the support structure is connected to the said rotor while the support strucure and the said rotor are relatively rotatable.

3. Control apparatus responsive to rotary movement of a rotary drive member, the control apparatus being of the type having a first rotor and a second rotor, the rotors being relatively axially movable, one of the rotors being connected to the rotary drive member for rotation therewith, actuator meansin engagement with each of the rotors and joining the rotors together and normally urging relative axial movement in given directions between the rotors, the actuator means including weight members which are movable in response to centrifugal forces to urge relative axial movement of the rotors in directions opposite to said given directions, the improvement comprising:

fixed support structure engaging the first rotor limiting axial movement thereof while permitting rotary movement thereof,

switch mechanism carried by the support structure,

the second rotor having an engagement portion which is engageable with the switch mechanism and movable with movement of the second rotor for operation of the switch mechanism.

4. The apparatus of claim 3 in which the fixed support structure encompasses a portion of the first rotor so that the fixed support structure is connected to the first rotor while permitting rotary movement of the first rotor with respect to the support structure.

5. Control apparatus comprising:

a pair of coaxial relatively axially movable rotor members, there being a first rotor member and a second rotor member,

centrifugally responsive actuator means joined to the rotor members for relative axial movement between the rotor members upon operation of the actuator means as the rotor members rotate one with the other,

the first rotor member having a peripheral groove therein,

a connector member having a portion within the groove of the first rotor member and partially encompassing the first rotor member so that the connector member and the first rotor member are joined one to the other for rotation of the first rotor member with respect to the connector member,

switch means carried by the connector member,

the second rotor member having a portion movable with respect to the switch means for operation thereof.

6. The apparatus of claim 5 in which the portion of the connector member which is within the groove of the first rotor member encompasses more than one-half of the rotor member.

7. The apparatus of claim 5 in which the connector member has portions within the groove of the first rotor at diametrically opposed spaced-apart positions of the peripheral groove of the first rotor member.

8. In combination, a rotary shaft, stationary support structure, and control apparatus comprising:

a first rotary member encompassing the shaft and joined thereto for rotation therewith,

a second rotary member encompassing the first rotary member and axially movable with respect thereto,

centrifugally operable actuator means joined to the rotary members for relative axial movement thereof,

connector means connecting the first rotary member to the stationary support structure and permitting rotation of the first rotary member with respect to the stationary support structure,

switch mechanism carried by the connector means,

the second rotary member including operator means for operation of the switch means with axial movement of the second rotary member.

9. The combination of claim 8 in which the first rotary member is secured to the shaft for axial movement therewith.

10. The combination of claim 8 in which the connector means is secured to the stationary support structure.

11. The combination of claim 8 in which the connector means is axially movable with respect to the stationary support structure.

12. The combination of claim 8 in which the stationary support structure has an opening therein and the connector means includes a stud which is axially movable within the opening in the stationary support structure.

13. The combination of claim 8 in which the first rotary member has a peripheral groove therein and the connector means has a portion within the peripheral groove.

9 14. The combination of claim 13 in which the portion of the connector means which is within the peripheral groove of the first rotary member is arcuate and extends around at least one-half the periphery of the first rotary member.

References Cited UNITED STATES PATENTS 10 8/1967 Van Golverdingeschut U.S. Cl. X.R.