US1926339A - Centrifugal switch - Google Patents

Description

Sept. 12, 1933. c KINDL ET AL 1,926,339

CENTRIFUGAL SWITCH Filed Dec. 30, 1931 UNITED STATES PATENT OFFICE CENTRIFUGAL SWITCH Carl H. Kindl and Zerbe C. Bradford, Dayton, Ohio, assignors to Delco Products Corporation, Dayton, Ohio, a corporation of Delaware Application December 30, 1931 Serial No. 583,898

11 Claims. (Cl. 200-80) This invention relates to centrifugal switches f t r si p ti f t C a a yi and more particularly to centrifugal switches m m er is rendered ineffective. used for controlling the starting circuit of an Further Objects and advantages of t pres nt alternating current t r, invention will be apparent from the following It is one of the objects of the present invention description. reference being had o the B-COOm- 60 to provide a centrifugal switch which is rugged Denying drawing w r inapreferred embodiment and durable and can be produced at low cost. of One form of the present invention is a y In order to accomplish this object the present showninvention provides a construction the parts of In the drawing! which can be manufactured from sheet material 1 is a fragmentary ud a Sec ional 65 parts. view of the electric motor segment with a cen- In the disclosed embodiment of the invention tiiiugai switch embodying the p e t i vention. the centrifugal device which operates the switch Fig. 2 is a fragmentary View Similar to Fis- 1 comprises three principal parts made of formed showing the switch in another its Operating sheet metal, namely, two weight members one on Positionseither side of the shaft and a bracket mounted 3 is a sectional View 011 the line 33 of on the shaft for pivotally supporting the weight members upon parallel axes at right angles to 4 is a sectional View On the li e 4-4 of the axis of the shaft. The weight members are h ld i inward position against t motor haft Fig. 5 is a perspective view of the bracket for by two coiled springs each connected with both supporting the Weight members o the Centrifugal weight members. The weight members have devicefingers movable substantially longitudinally of the 6 ShOWS a P pect ve view of the two h ft t press against a switch actuator plate weight members in the same relation to one an- 25 through which t haft extends Then, the other after each has been assembled with the principal parts of the switch are made from sheet bracket as Shown in the Springs t o l material. That is, a contact carrying member the Weight members as i a d by the dot-andis preferably stamped or punched from resilient dash linesconducting material, and a contact actuator Referring to Fig 0 si ates a field frame 30 plate is made preferably of insulating material Carrying a stat r frame 21 which in turn carries h as b k 1it stator windings 22 and 23. The frame 20 sup- It is also an object of this invention to provide ports an end frame 24 providing One f the bea anormally biased resilient contact carrying memings 25 for the armature Shaft 6 W ch Supber and an actuator plate so arranged therewith ports a rotor The h f 2 h s a knurled th t; th t t plate does t appreciably portion 28 over which the laminations 29 of the interfere with the resilient action of the contact motor have been P carrying member due to its normal biasing, but T knurled portion 28 0f th shaft 26 rethat tends to Strengthen the Contact carrying ceiv esabracket 30 made of formedsheetmetaland member and reduce the effective resilient porhaving a tubular Portion 31 which is Dress-fitted tion thereof so as to effect greater pressure at the Over the knurled porno? The braifket 30 contacts for a given force applied to the switch chides fiat made Portlon 32 located m a plane actuator plate than would otherwise be obtained, transverse of the c of the tubular sleeve and that tends to reduce possibility of permanent non f thls plane portion 32 Weeds 45 deformation and fatigue of the contact carrying :52? ars eatch winchltermmatfes Into member. This is accomplished by securing the ears ex en mg m p i parallel to the axis of the tubular sleeve ortion 31 Th contact actuator plate to the midportion of the ears 34 are a ertured t 35 6 Contact y g member on one side thereof inp a p 0V1 e armgs for the weight members. termediate it and the centrifugal actuating mech- The Weight members 40 are made exactly alike to anism, and in s Way that said Contact yfrom formed sheet metal. Each weight member ing member is substantially free to flex in one dimay b said t comprise U-shaped or ch n l rection due to its biasing, but has a substantial portion 41 integral with a finger bar portion 42 portion covered by the actuator plate so that when which forms an acute angle with the adjacent a force is applied thereto by the actuating mech-' side of the channel portion 41. The finger bar 55 anism and the contacts become engaged, a part portion 42 is provided with a plurality of fingers 43 normally engaging a movable actuator member 60 of the switch. The finger bar portion 42 is provided with oppositely extending lugs 44 and 45, the latter being longer and being provided with a notch 46 for receiving one end of a spring 47. The end of each spring 47 is hooked over a notched lug 48 extending from the .fi-nger bar portion 42 near where the bar 42 joins the channel portion 41. The lugs 44 and 45 provide the journals of the weight members 40, said journals being received by the apertured ears 34. Since the distance between the ends of the extending lugs 44 and 45 is greater in length than the distance between the ears 34 as shown in Fig. 5, one of these ears 34 is not bent into a plane at right angles to the bar 33 until after the weight member 40 is assembled therewith. After assembling the weight members 40 with bracket 30 which is done preferably before the bracket 30 is mounted upon the armature shaft, the springs 47 are located in position as shown in Fig. 6. The springs 47 are attached at one end to the lugs 48 of the weight members 40 and at their other end to the journal lugs 45 of the weight members. In this way the springs operate to urge the channel portions 41 towards the shaft 26. The plate portion 32 of the bracket 30 carries two felt or fiber discs 49 which are engaged by the fingers 43 when the weights fly outwardly as indicated at 41a in Fig. 2. It will be seen that the fingers 43, when located at positions 43a, engage the discs 49 which serve to prevent noise which might occur if the fingers were to engage metal parts while the motor is accelerating. A felt disc 50 is attached to each channel member 41 in order to prevent noise due to vibration of members 41 when in contact with or in close proximity to the shaft 26.

When the motor is at rest the fingers 43 as shown in Fig. 1 normally engage the non conducting switch actuator plate 60, attached by rivets 61 to a leaf spring member 62, having arms 63 attached by rivets 64 to a non-conducting plate 65 attached by screws 66 to the motor end frame 24. Both the plate 60 and the leaf spring member 62 are apertured to receive the shaft 26. The plate 62 has an extension 67, carrying a contact 68 engageable with a relatively stationary contact 69 on a conducting blade 70 attached to a nonconducting plate '71.

When the speed of the motor increases the Weights 41 move into the positions 41a shown in Fig. 2 thereby causing the fingers 43 to move toward the right into the positions 43a whereupon the leaf spring conductor 62 will move toward the right due to its own resiliency until this conductor is stopped by engagement of its extension 67, with a bracket 72 attached to the plate 71. When the current of the motor is shut off and the speed of the motor shaft diminishes, the weight portions 41a move toward the shaft under the influence of the springs 47, thereby causing the fingers 43 to move toward the left into engagement with plate 60 to cause the contact 68 to engage the contact 69 thereby completing the starting circuit of the motor so that the motor is in condition for operation again.

While the form of embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows.

1. A centrifugal switch comprising in combination, a shaft, a frame providing a bearing for the shaft, a switch supported by the frame and including a resilient leaf contact carrying member having a contact actuator plate secured to one side thereof and thru which said shaft extends, said plate being freely movable longitudinally of said shaft, and a centrifugal device for actuating said contact carrying member and comprising a bracket carried by the shaft and providing pairs of bearing members on opposite sides of the shaft, said bearing members providing parallel axes of rotation at right angles to the axis of the shaft, and like weight members each having lugs journalled in a pair of bearing members, each of said weight members being formed of sheet metal so as to have a weight portion located near the shaft on the side of the bracket remote from the switch, and each having a finger extending from the bearing member toward the switch actuator plate, springs urging the weight portions toward the shaft and the fingers toward the switch actuator plate, pads mounted on said weight portions to contact said shaft and arrest motion of said weight members due to the urging forces of said springs, said weight portions being formed to provide mountings for said pads such that said pads arrest motion of said weight members to prevent said fingers from being urged against said actuating plate with suflicient force to deform said contact carrying members.

2. A centrifugal switch comprising in combination, a shaft, a frame providing a bearing for the shaft, a switch supported by the frame and including cooperating contacts, a resilient leaf contact carrying member anchored at one end and having one of said contacts mounted near its other end, a contact actuator plate secured to one side of said contact carrying member near the mid-portion thereof and thru which said shaft extends, said plate being freely movable longitudinally of said shaft, and a centrifugal device for actuating said contact carrying member and comprising, a bracket carried by the shaft and providing pairs of bearing members on opposite sides of the shaft, said bearing members providing parallel axes of rotation at right angles to the axis of the shaft, and like weight members formed of sheet metal and each having lugs journalled in a pair of bearing members, said weight members being formed so as to have a weight portion located near the shaft on the side of said bracket remote from the switch, and each having a finger extending from the bearing member toward the switch actuator plate and adapted to engage the switch actuator plate, springs urging the weight portions toward the shaft and the fingers toward the switch actuator plate, said actuator plate being intermediate the contact carrying member and fingers and covering a portion of said contact carrying member so that it effectively stiffens said contact carrying member after engagement of said contacts is effected by the action of said fingers, and means for arresting motion of said weight members.

3. In a centrifugal switch, the parts of which can be made substantially entirely of sheet material and mainly by machine operations, and that is adapted to be assembled with a shaft and a frame providing a bearing for said shaft, the combination comprising, a switch supported by the frame and including cooperating contacts, a resilient leaf contact carrying member anchored at one end and having one of said contacts mounted thereon, said resilient contact carrying member being normally biased to disengage said contacts, a contact actuator secured to one side 1 of said contact carrying member thru which said shaft extends, said plate being freely movable longitudinally of the shaft, and a centrifugal device for actuating said contact carrying member and comprising, a bracket carried by the shaft and providing pairs of bearing members on opposite sides of the shaft, said bearing members providing parallel axes of rotation at right angles to the axis of the shaft, and like weight members each having lugs journalled in a pair of bearing members and a weight portion on the side of the bracket remote from the switch, each weight member also having a finger extending from the bearing member toward the switch actuator plate, and springs urging the fingers toward and into engagement with the switch actuator plate, said springs being adapted to overcome the biasing force of said contact carrying member thru engagement of said fingers with said actuator plate.

4. In a centrifugal switch, a switching means comprising in combination, a resilient leaf contact carrying member insulatingly anchored at one end, cooperating contacts, one of which is mounted on said contact carrying member, said contact carrying member being normally biased to separate said contacts, and a contact actuator plate secured to the opposite side of said contact carrying member from said contact, and covering a portion of said contact carrying member intermediate the ends thereof, said contact actuator plate covering a sufficient portion of said contact carrying member to appreciably shorten the effective resilient portion of said contact carrying member when engagement of said contacts is effected thru force applied to said actuator plate.

5. In a centrifugal switch, a switching means comprising in combination, a resilient leaf contact carrying member insulatingly anchored at one end, means for making electrical connection to the contact carrying member, cooperating contacts, one of which is mounted on said contact carrying member, means for making electrical connection to the other of said contacts, said contact carrying member being normally biased to separate the contacts, and a contact actuator plate secured to one side of the contact carrying member and near the mid-portion thereof,

6. In a centrifugal switch to be used on a rotating device having a shaft, an actuating mechanism, comprising in combination, a bracket carried by the shaft and providing a pair of bearing members on opposite sides of the shaft, said pairs of bearing members providing parallel axes of rotation at right angles to the axis of the shaft, and like weight members each having lugs journalled in a pair of bearing members, each of said weight members having a weight portion located near the shaft, and each having a finger extending from the bearing members and away from said weight portions, said weight members also having connector lugs formed thereon, and

springs connected to said connector lugs for urging the weight portions toward the shaft.

7. In a centrifugal switch to be used on a rotating device having a shaft, an actuating mechanism comprising in combination, a bracket providing a pair of bearing members on opposite sides of the shaft, and like weight members formed of sheet metal and having lugs formed thereon some of which are longer than others and provided with notches, some of said lugs being journalled in the bearing members to provide a pivotal mounting for the weight members, said weight members also having substantially U- shaped weight portions formed on one end thereof and fingers on the opposite side of the pivotal mounting from said weight portions, and springs connected to the longer lugs to resist centrifugal force on said weight members, and pads secured to the weight portions to arrest motion of the weight members caused by said springs.

8. In a centrifugal switch to be used on a device having a shaft, an actuating mechanism made substantially entirely of sheet metal, and including in combination, a bracket having a tubular portion press-fitted upon the shaft and pairs of apertured ears on opposite sides of the shaft, said pairs of apertured ears providing parallel axes of rotation at right angles to the shaft, light weight members having a weight portion formed thereon and located on one side of said axis of rotation, each weight member also having a finger extending away from the axis of rotation and the weight portion and lugs journalled in a pair of said ears.

9. In a centrifugal switch, a weight member formed of sheet metal and comprising, a substantially U-shaped weight portion, fingers integrally formed with said weight portions and forming an acute angle with one side of the U, and lugs formed thereon for pivotally mounting said Weight members.

10. In a centrifugal switch, a weight member formed of sheet metal and comprising, a substantially U-shaped weight portion, fingers integrally formed with said weight portions, and lugs formed on the sides of the weight members intermediate the extending ends of said fingers and the weight portions for pivotally mounting said members.

11. In a centrifugal switch, a support bracket formed of sheet metal and comprising, a tubular portion, a plane portion secured to the tubular portion and substantially perpendicular to the axis of said tubular portion, said plane portion terminating at its ends in angularly extending portions having apertured ears formed thereon, said ears being substantially parallel to the axis of the tubular portion so that said apertures provide axes of rotation perpendicular to the axis of the tubular portion.

CARL H. KINDL. ZERBE C. BRADFORD.

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