US2668043A - Clutch type speed responsive device with magnetic link - Google Patents

Description

1954 e. A. WINTERBURN ETAL 2,668,043

CLUTCH TYPE SPEED RESPONSIVE DEVICE WITH MAGNETIC LINK Filed March 31, 1951 f 17/ may G769 Ami-$655M)? Patented Feb. 2, 1 954 ED STAT PAT'E NT OFFICE CLUTCH TYPE SPEED RESPONSIVE' DEVICE. WITH MAGNETIC, LINK ApplicationMal-cli 31, 1951, Serial-No. 218,631

22, Glaimsv. 1. This invention relates to a device for trans-- mitting motion through combined hydraulic and magnetic: links, particularly asappliedtoswitches for indicating or making effective the motionor rest condition of a driving mechanism; for thepurpose of controlling it or associated devices.

It frequently desirable to supervise or control themode of" operation of machines having rotary or other motions. Examples of such supervision or control are remote indication of the response' of an electric motor to the operators. control; protective supervision ofamotor to insure that it has slowed down or stopped before reverse power is applied, control ofone machine according to the operation of another machine; introduction of a time delay betweenthe start of oneoperation andthe start oi an-- other, and analysi'sof various machine-functions, (Dbjectsof the present invention areto-providearr improved. actuating device which responds to rotary motion in either direction, which-distinguishes between. directions of motion and be-- tween. motion and standstill, which permits counting'by providing an impulse per revolutionof' a-v shaft, which: provides an interlock betweenvarious movingpartsof'an installation; which can be used as a jogging switch and interlock for devices such as: conveyors, and which selectively operates a plurality of independent switches according to the motion or rest con-= dition of the mechanism under study' or control. Other-object's are to introduce an adjustable or fixed time delaybetween the-application of drivingmotion toadevice and actuation. of dependent.

devices such as switches accordingly, to: provide a: zero: motion indicator, and to provide. a. device o the general: type indicated. above: winch simple and inexpensive and; yet rugged, reliable, accurate andparticularly also very versatile for application: to; a large variety of functions;

Devices according to the invention comprise a. housing containing; viscous liquid, at driving element such as a disk; and a driven member such. as another disk, mounted in. the, housin with driving: and, driven. portions adjacent. to each other. and with the liquid providing hydraulic, coupling. betweenthetwo portions, means for.transmitting movementv to the driving element, an. actuatednmmber, a, magnet or iron element carried. by one of the two members, and a. magnet. or, ironv element, carried by. the

other member, magnet. and. iron-vv elements. being.

placed,.magnetically to. respond, to. a, change. of. position, therebetwe en, whereby movement. of: the. driving element causes change of position of the driven member a-iiecting the actuated member. Preferably the actuated member switch, but any mechanical operator can be used instead, such as a lever for moving a signalingelement or opening or closing: a latch or look mechanism. Biasing means such as a weight eccentri'cally mounted onthe driven member, or spring means are used for yi'el'dingly urging the driven member to holdits magnetic element in a normal position, so that rotation of the driving element causes the driven member to move the magnet to a position displaced clockwise or counterclockwise from the normal position to affect the other magnetic element and to actuate the device, If one or a plurality of actuated members are disposed with their magnetic" elements such as iron armatures adjacent the path of the driven magnetic element, at normal position or at one or more displaced positions on each oreitherside of'a normalposition or'at both normal and displaced positions, these members can be actuated" ina variety of ways, independently ordiscriminatory of the direction of rotation.

To provide fora minimum starting speed and to-i-ntroduce a time delay between the beginning of rotation of the driving element suchas a disk and the actuationof one of the devices through. the driven member such as another disk, the liquid coupling between the disks can be varie so that rotation of the driving disk does not move the driven disk sufiiciently to a-fiect the magnetic element of the actuated device, or to introduce a predetermined slip between driving element and drivenmember. The'magnitude of liquid coupling can bevaried by changing the bias suchasweight of the magnet or other part mounted on the driven member, by changing the viscosity of the liquid in the housing or, with particular convenience, by adjusting the spacing between the disks;

In a further-aspectthe driven member carries one or" more abutments, and the housing or a structural component referred thereto carries a stop disposed in the path of an abutment so that when the driving element moves the driven member the abutment engages the stop to hold the driven member in a predetermined position, the magnetic element of one or, more oi" the actuated devices being located in corresponding position. A plurality of abutments can be disposed in spaced positions on the driven element to move along spaced paths, the. stop being. ad'- justabl'e into a selected path thereby presel'ecti'ng is athe position of magnetic elements of the driven member and the actuated device.

In a more specific aspect the disks constituting driving element and driven member are only partially immersed in the viscous liquid, and are disposed with opposed faces parallel and closely adjacent to provide a capillary space for the viscous liquid therebetween, the disks being effectively coupled by a controllable capillary force acting in the space, so that when the driving disk is rotated liquid will be distributed over said faces and the driven disk will be coupled tothe driving disk with the above mentioned speed discrimination and time delay.

These and other objects and aspects of the invention will be apparent from the following description of several embodiments which refer to a drawing wherein Fig. l is a side elevation of an actuator according to the invention;

Fig. 2 is an end elevation corresponding to Fig. 1;

Fig. 3 is a section on line 3-3 of Fig. 2, with parts in elevation;

Fig. 4 is a section on line 4 of Fig. 3;

Fig. 5 is an enlarged section similar to Fig. 3, through switch and housing, with the magnet in elevation and the other parts omitted;

Fig. 6 is a section corresponding to Fig. 4 of a second embodiment; and

Fig. '7 is a section similar to Fig. 5 of a third embodiment of the invention, certain parts being omitted in Figs. 6 and 7.

The embodiment of the invention which is illustrated in Figs. 1 to 5 has a housing I enclosing a chamber partially or wholly filled with a viscous liquid 2 such as hydraulic fluid of selected viscosity and mounting a shaft 3 which carries a driving disk 4 fixed to the shaft and a driven disk 6 freely rotating on the shaft. The driven disk 6 carries a small permanent magnet l at its periphery. Mounted outside the housing is a mercury switch 8 or mechanical device 8a. (Fig. 7) having a movable iron element 9 or 9a respectively. It will be noted that the magnetic elements 1 and 9 define a comparatively concentrated region of optimum response therebetween.

The housing I has a journal box H in which are mounted two roller bearings l2 and a conventional sealing ring l3 respectively for supporting the shaft 3 and preventing loss of the hydraulic fluid 2. The driving disk 4 is spaced from the inner bearing 12 by washers l4 and fixed to the shaft 3 with a screw IS. The inner end of the shaft I? is of reduced diameter to form a shoulder [8, the reduced portion being threaded to receive a nut [9 for clamping the inner race of a roller bearing 2! against the shoulder l8. The driven disk 6 is secured to the outer race of bearing 2| by a set screw 22, the driven disk 6 being free to rotate independently of the shaft 3, except as will be described hereinafter.

The driven disk 6 carries near its periphery a magnet I for example secured by a machine screw 24 to a rearwardly extending boss 23. The magnet l is held close to the rear wall 26 of the housing, which rear wall is formed of nonmagnetic material such as molded plastic.

Attached at the rear of the housing I is a bracket 21 to which one or more spring detents 28 for firmly holding a mercury switch 8 are attached by screws 29 passing through holes 3!. Other mounting holes em and Slb are provided to attach additional detents (not shown) for holding additional switches serving purposes to be set forth below.

As shown in Fig. 5 the mercury switch 8 can be of conventional design with a glass envelope 30 and two leads 32 one of which extends into a pool of mercury Hg while the other is electrically connected through a spiral spring 33 to the armature 9 with wire finger 34 which dips into the pool of mercury thus completing an electrical circuit when the magnet l attracts the armature 9. Instead of the mercury switch 8, a pivoted lever 8a of a mechanical actuator may be mounted adjacent the rear wall 26 of the housing I as shown in Fig. 7. The lever 8a carries an armature 9a, and it will be understood that in this and analogous embodiments with little limitation on size or weight of the armature, components 1 and 9a, constituting magnetic elements, can be interchanged. It will be further apparent that the separating wall 26 can be part of a larger compartment, the magnetic link i, 9 providing for mechanical separation of driven member 6 and actuator 8 or 8:1. Instead of a magnet and an iron armature, two magnets can be used as magnetic elements.

In the position shown in Fig. 5 with magnet I opposite armature 9, the latter is attracted, making contact at Hg and 35 as indicated in dot and dash outlines.

As shown in Figs. 3 and 4 the driven disk 6 carries a pair of vanes or abutments 3? near its periphery. A screw 38 fastened in the top of the housing I extends with its end into the path of the vanes 3? for the purpose of stopping rotary motion of the driven disk in either direction when the magnet l and the vanes 3? are in one of the positions la shown in Fig. i in dot and dash lines. In either of these positions the magnet i will operate a mercury switch held in one of the clips or detents mounted by means of holes Zia (Fig. 2) as described above. The armatures of these switches can be disposed in appropriate positions to either sid of the central position shown in Figs. 2 and 3. It will be further understood that the lateral distances of these armatures can be rendered adjustable by appropriate conventional means.

As shown in Fig. 6 two or more vanes or abutments 31a or 311) may be provided at either side of a line passing through the shaft axis and the magnet l in neutral position. The abutments 31a nearest that line are located nearer to the axis of the disk than vanes 37?). In this embodiment a modified stop screw 38a is adjustable radially of the driven disk so that it can be moved into the paths of the outer vanes 31b as shown by its position in solid lines in Fig. 6 or into the path of the inner vanes 3711i as shown by its position shown in broken lines 3821 so that it can be selectively stopped by either a vane 3w or 3% respectively.

When the stop screw 36a is in the position shown in broken lines the driven disk will be stopped in one of the broken line positions in of the magnet. When the stop screw 38a is in the position shown in solid lines the driven disk will be stopped with its magnet in one of the broken line positions Tb. As already indicated, switch means 8 or mechanical actuator devices 3a may be mounted at positions corresponding to detent mounting holes 3la or 3th which again correspond respectively to vanes 37a or 3172. The switch 8 can also be moved from a detent seu e t0 the holes 3m to a detent secured in the 5.: holes 3131. as the:v stop: screw: 3.311 is: adjusted. to thepath of vanes 331117..

As shownin Figs. hand-3 thehousing l; is provided"v with an; opening i] providing to the setscrew' 221 which ia-sten-sthe-dish: 6 to the bearing. 21.. A; screw 4:22 provides a closure for theopening d].

The-.operation of the actuator is as follows.

Assuming. that the: actuator is mounted in the position shown, the weight of the magnet inormallyholds the driven disk. tin the rest position shown in the. drawing insolid. lines. In this position the magnet-.11; is in operative relation to armature a (Fig. 5) or 9:1. (Fig. 7) such that the armature causes-the switch 8 to close or the actuating lever 3a to. move to a desired position. Whenthe driving shaft 3,.which is connected to arotating mechanism, for example the shaft of a motor beginsatorotatathe hydraulic liquid effectively couplesthe driving disk to the driven disk:causing the drivendisk to rotate in the same direction. The disk. and magnet return to normalu position, reactuating switch 8, only upon stoppage, or if desired minimum speed, of the driving member.

If thehousing Iis full, or nearly full, of hydraulic liquid 2 the driven disk will respond relatively' quickly. Ifthe housing is only partially full as shownin. Eigs. 2' and 4, the hydraulic liquidwill be drawn between the disks at a certain rate until sufficient interracial friction or capillary attraction is provided to overcome the tendency-of-Ithemagnet or other weight to hold the driven disk in normal or rest position. In addition to amount of liquidand speed rotation, the

response time also depends on the viscosity of the liquid and'the spacing between driving and drivendisks. The disk will then move the magnet to the position defined by stop 33 or to one of: thepositions id or lb. More time is needed to lift the magnet to a more remotely displaced position such as it than to a less remotely displaced pcsition-such as To.

As the magnet moves from its normal position it will move out of operative relation with the switch 8'. allowing the armature located adjacent the normal position lot the magnet to move its contact finger 34 from-the mercury pool, with a certain time delay between beginning of motion and actuation of the switch. When the F magnet '7 moves into one of the displaced positions id or iii it will remain there operating the armature of a switch if such is located in that positicn. Whether the driven disk moves in either clockwise or counterclockwise direction the switch at neutral position will be allowed to open. If switches are mounted at the displaced positions one of them will be actuated. Thus the switch. at normal position may be employed to discriminate between rotation and non-rotation of the mechanism attached to the driving shaft 3, while switches located adjacent displaced positions la or lbcan be used to indicate the direction-of rotation-of the shaft.

Displaced switches alone, without normally affected switch 8 will perform the function of switch 8,? as well'as the directional function, with an additional time delay, if desired adjustable by means of a stop similar or analogous to screw 38a.

The return time upon stoppage of shaft 3 or rotation, fallingbelowa given rate can be ad- .li stedto. determine time intervals between-rerspective conditioning. of; two switches in post.-

tions, such; as 3.1; and. 31mm; between actuati n andircactuationphasingleswitch at-.3 l

If the, :stop: 38: isgentirely: withdrawn, the actu: ator; can.bemsed; as a: counter effecting one or more impulses per shaft rotation, the. pha-serelation; of: movement: and impulse and the number of. impulses? depending; upon the arrangement of switchesand selection of coupling characteristics..-

In additiomswitches .locateda-t displacedpositions will; givea qualitative indication of the speedi of the: shaft; sinceia switch located adjacentiailessremotely displacedpositionsuch as 10: will respond at a givenspeed: prior; to the response of a switch located at a more remotely displaced position such: as lb; analogously, two switches at different positions will respond: to differentaspeedsr: with the same time delay. Generally speaking; the three variables, switchposition; speed. of; driving member and response delay, canibe definitely;interrelated.

The: timedelayrbetweenthe beginning of rotation of the drivendiskzda and the operationof a switch may be controlledor adjusted by varying. either the hydrauliocoupling between the disks or theadjustment-off the stop screw 38a. or the vane positions; or. by; changing the bias of the driven disk 6 This can be done by changing the weighting means of: driven disk 6; or by adjusting: biasing; means. which. are independent of' gravity.- Fig. 6 shows assuch meanssprings 5|, 52. interposed betweenv housing I and. disk 8. Such springs can-be rendered adjustable by conventional meansand set tozbias-the driven member. in the-desirednormal.position. The hydraulic. coupling betweenthe disks may be increased set screw: 22'; By. insertingascrew driver through this opening thesetscrew. 22'may. be loosened and the driven disk. shifted axiallyon the bear- J ing 2! to adjust the spacing between the disks.

The weighting of the driven disk may be increased. by replacing the magnet T with one of greater. Weight, or by adding a non-magnetic weight. may. be adjusted'in' or out of the paths of one of the stopvanes 37a or 3'") thereby determining the angle through which the driven disk may rotateand'also selecting aswitch at one of the displacedpositions Fa-or lb for continuous operationby themagnet 7.

By pro-perchoice of the various effective characteristics such as fluid viscosity, degree of filling, disk distanceand'biasing force,- a minimum effective speed as well aspredeterminedtime-delay'of actuation upon reaching such speed can be selected to efiect response of' a switch or switches-or-other actuators at either normal or displaced position. Thus a switch 8 in the positionof'Fig; 2 can be made to respond only if the shafts" rotates at agiven speed, with predeterminedtimedelay afterthat speed is reached.

Bydifferently distancing the corresponding driven stops (such- 31) on either side of a fixed stop (such as 38*), d-ifferentresponse speeds and time delays can be provided for'respective scnsesc'fmovement; Adjustability of these-distances and of" the corresponding response characte-ristics be provided by conventional means: applied to :mov-able or-fixed stops or both.

It willi l'lQW be. evident: that: devices. built in.

As previously described the stop 38a accordance with the invention are adaptable to varous purposes involving functions such as time delay, jugging, directional discrimination, distinction between operation and non-operation, speed detection, interlocking of several components, speed limiting, supervision of reversing, overrunning control, protection against back spin, counting, and combinations of such functions.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall within the scope of the appended claims.

We claim:

1. An actuator comprising a housing containing viscous liquid, a driving element and a driven member mounted in said housing with driving and driven respectively adjacent to each other with said liquid providing hydraulic coupling therebetween, means for transmitting movement to the driving element, an actuated member mounted outside said housing, a concentrated magnetic element carried by one of said members, a second concentrated magnetic element carried by the other member, and stop means for limiting conjoint movement of said driving element and said driven member, said magnetic elements being placed relatively to said stop means to move said actuated member upon change of position therebetween, whereby moveent of the driving element causes delayed response of said actuated member.

2. Actuator according to claim 1 further comprising biasing means yieldingly urging the driven member to hold its magnetic element in normal position, whereby rotation of the driving element causes the driven member to change said position, affecting said actuated member.

3. Actuator according to claim 1 wherein said stop means includes corresponding stop members mounted on said driven member and said housing respectively, to stop movement of the driven member after initial movement, while said driving element continues to move.

. 4. An actuator comprising a housing containing viscous liquid, a driving rotatable disk and a driven rotatable disk both mounted in said housing with said liquid providing hydraulic coupling between the disks, means for transmitting rotary movement to the driving disk, a concentrated magnetic element carried by the driven disk, stop means for limiting conjoint movement of said disks, and an actuated device having a concentrated magnetic element fixed relatively to said housing to respond to a change of position between the magnetic elements.

5. Actuator according to claim 4 further comprising means for biasing said driven disk to urge its magnetic element to a normal position, whereby rotation of the driving disk causes the driven disk to move its magnetic element from said normal position to affect said actuated device.

6. Actuator according to claim 5 wherein said biasing means normally urges the magnetic element of said driven disk to a normal position and wherein said second magnetic element is located adjacent said normal position, whereby rotary movement in either of two directions actuates said device.

'7. Actuator according to claim 5 wherein said biasing means normally urges the magnetic element of said driven disk to a normal position and wherein said second magnetic element is disposed at a location adjacent the path of the first magnetic element but spaced from said normal position, whereby said device is actuated by rotary movement in one direction.

8. Actuator according to claim 5 comprising an additional actuated device said driven disk being normally biased to urge its magnetic element to a normal position and said two actuated devices being located with their magnetic elements adjacent the path of the magnetic element of the driven disk at each side of said normal position respectively, whereby one of said devices i operated according to the direction of said rotary movement.

9. Actuator according to claim 5 having two additional actuated devices and being characterized in that said driven disk is normally biased to urge its magnetic element to a normal position and in that said three actuated devices are located with their magnetic elements adjacent the path of the magnetic element of the driven disk, one element adjacent said normal position, and one of the remaining elements at each side of said normal position respectively, whereby one of said devices is selectively actuated in the absence of said rotary movement or by rotary movement in either direction respectively.

10. Actuator according to claim 5 wherein said biasing means comprises spring means interposed between said driven disk and said housing to urge its magnetic element to a normal position, whereby rotation of the driving disk causes the driven disk to move its magnetic element from said normal position and to affect said device.

11. Actuator according to claim 4 wherein said driven disk carries a magnet and said actuated device carries an iron armature element.

12. An actuator comprising a housing containing viscous liquid, a driving rotatable disk and a driven rotatable disk both mounted in said housing with a space therebetween and with said liquid providing hydraulic coupling through said space, means for transmitting rotary movement to the driving disk, a magnetic element carried by the driven disk, an actuated device having a magnetic element fixed relatively to said housing to respond to a change of position between the magnetic elements, and means for adjusting said coupling thereby to vary a predetermined period between initiation of driving and effective change of position between the magnetic elements.

13. Actuator according to claim 12 characterized in that said adjusting means comprises means for varying the space between said disks.

14. Actuator according to claim 13 further characterized by shaft means adjustably carrying said driving disk, bearing means for rotatively supporting said driven disk on said shaft means and means for adjusting the distance between said disks.

15. Actuator according to claim 14 wherein said driving disk is fastened to said shaft and said driven disk is axially adjustable on said bearing.

16. The actuator according to claim 14 wherein said driven disk is fastened to said bearing with a set screw and said housing has an opening afforcling access to said screw.

17. An actuator comprising a housing containing viscous liquid, a driving rotatable disk and a driven rotatable disk both mounted in said housing with said liquid providing a hydraulic coupling between the disks, means for transmitting rotary movement to the driving disk, a

magnetic element carried by the driven disk, an abutment mounted on the driven disk, a stop mounted on the housing and disposed in the path of said abutment to hold the driven disk in a displaced position after a predetermined period of rotation of the driving disk causing the driven disk to move its magnetic element from a normal position to said displaced position, and an actuated device having a magnetic element fixed in predetermined position relatively to said stop, whereby the two magnetic elements can be held in predetermined relative position during rotation of the driving disk.

18. Actuator according to claim 17, wherein said driven disk carries an abutment on either side of said stop.

19. Actuator according to claim 17 characterized in that said driven disk carries a plurality of abutments radially spaced to stop the driven disk in at least two displaced positions at one side of said stop, said stop being adjustable selectively to extend into the path of one of said abutments.

20. An actuator comprising a housing containing viscous liquid, a driving rotatable disk and a driven rotatable disk mounted in said housing, said disks being only partially immersed in said liquid, means for transmitting rotary movement to one of the disks, a concentrated magnetic element carried by the other disk, and an actuated device having a second concentrated magnetic element fixed relatively to a normal position of the first magnetic element to respond to a change of position between the two elements, the opposed faces of said disks being distanced to form a capillary space for liquid therebetween so that said disks are coupled by a predeterminable capillary force, whereby the driving disk when started by said transmitting means distributes liquid over said faces and the driven disk is moved to afiect said device after a time interval dependent upon the building up of said capillary force.

21. Actuator according to claim 20 characterized by means for adjusting the spacing between said disks to vary said capillary force, whereby said interval may be varied.

22. An actuator comprising a housing containing viscous liquid, a driving rotatable disk and a driven rotatable disk both mounted in said housing with said liquid providing hydraulic coupling between the disks, means for transmitting rotary movement to the driving disk, a concentrated magnetic element carried by the driven disk, stop means for limiting conjoint movement of said disks, an actuated device having a concentrated magnetic element fixed relatively to said housing to respond to a change of position between the magnetic elements, and biasing means including an eccentric weight on said driven disk for biasing the driven disk to urge its magnetic element to a normal position, whereby rotation of the driving disk causes the driven disk to move its magnetic element from said normal position and to afiect said device.

GEORGE A. WINTERBURN.

CLARENCE B. WALWORTH. LEROY E. LAWRENCE.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 111,677 Pottle Feb. 7, 1871 933,367 De Dion et al Sept. 7, 1909 1,001,065 Mursch Aug. 22, 1911 1,209,359 Tesla Dec. 19, 1916 1,271,092 Smith July 2, 1918 1,384,809 Smith July 19, 1921 1,655,647 Hornbostel Jan. 10, 1928 2,099,849 Holmes Nov. 23, 1937 2,245,596 Lindberg June 17, 1941 2,273,848 Ely et al. Feb. 24, 1942 2,347,613 Rodanet Apr. 25, 1944 2,415,916 Sloane Feb. 18, 1947 2,524,261 Kaminky Oct, 3, 1950 2,529,481 Brewer Nov. 14, 1950 2,600,011 MacDonald et al. June 10, 1952 FOREIGN PATENTS Number Country Date 562,799 Great Britain July 17, 1944

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