US1578837A - Reversible motor - Google Patents

Description

March 30, 1926. r 1,578,837

R. L. LEE

REVERSIBLE} MOTOR Filed March 13, 1924 5 Sheets-Sheet 1 X XX B WW4 March 30 1926. 1,578,837

R. L LEE REVERSIBLE MOTOR Filed March 13 19 24 5 Sheets-Sheet 2 Hrs 1422727712 5 E905! I Q March 30 1926. I 1,578,837 R. L. LEE

fi/ 11 .7, N I W Es J ZZar'n Eys Patented Mar. 30, 1926.

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Application filed-larch 13, 1994. Serial lio. 888,884.

To all whom it may concern: Be it known that I, RALPH L. Lnn, a c tizen of the United States of America, residing at Dayton, county of Montgomery, State of Ohio, have invented certain new and useful Improvements in Reversible Motors, of which the following is a full, clear, and exact description.

This invention relates to a power unit which in ludes an electric motor and mechanism operated by the motor for automatically reversing-the motor.

One of the difliculties, which the present invention seeks to overcome, is one which is apt to be encountered when the speed of the motor is relatively low. In devlces used heretofore the speed of the motor maybe insulficient to cause the reversing mechanism fully to complete its'cycle of operation whereby the motor is reversed. The result is that the motor will stop and cannot be operated in either direction until after the reversing mechanism is manually operated, although the causes of the slow speed of the motor be removed. I

One object of the present invention is to provide that the operation of reversing mechanism will either be completed by the operation of the motor or else the motor will stop while yet the reversing mechanism is in condition to cause the motor to resume operation when the conditions producing low speed or power have been removed. In other words, although the motor may be stalled, the reversing mechanism will not require manipulation before the motor can be started again.

Other objects are to improve the lubrication of the reversing mechanism and to reduce'noise.

A further object is to provide improvements in ap aratus for coolin the motor. Further objects and advantages of the resent invention will'be apparent from the ollowing description, reference being had to the accompanying drawings, wherein a preferred embodiment of one form of the present invention is clearly shown. I In the drawings: Fig. 1 is a side elevation of a motor and reduction gear unit embodying the present invention.

Fig. 2 is a wiring diagram of the electrical circuits and connections employed in said motor.

Fig. 3 is. view partly in section and partly in elevation of the motor and reversin mechanism therefor.

1g. 4 is a fragmentary sectional view taken on the line 4-4 of Fig. 3.

Fig. 5 is atop plan view of with the cover removed.

Fig. 6 is a sectional view taken on the line 6-6 of Fig. 5. v

Fig. 7 is a ragmentary top plan view similar to Fig. 5, but showing lifting cam in the op osite position.

the motor the brush 7 Fig. 8'is a view sim1 ar to Fig. 4, but showing the trip mechanism in the opposite position.

Referring to-the drawings, a motor. and gear housing unit represented as a whole by the numeral 20. comprises a gear housing 21 hich merges into a motor end frame 22. Field frame 23 comprises laminations 24 secured between annular plates 25 and 27 by rivets 26 and non-magnetic hollow; rivets 28".

Studs 28, passing through rivets 28", engage tapped holes 29 in frame 22 and receive nuts 30 which bear against plate 25. A brush supporting bracket is secured to plate 25 by nuts 36 whichengage the ends-of studs 28 which pass through the bracket 35.

nism being removable in assembled relation with the cover.

Field windings are supported by laminations 24, and an armature 51 and a commutator 52 are mounted u on a shaft 53 which is journalled in bearings 54 and 55 provided. by housing 21. A worm 56 on shaft 53 cooperates with a worm gear 57 mounted on a shaft 58" rotatably supported by frame 21.

Motor reoersing mch'am'sna The motor brush rigging is mounted upon the bracket 35 and is removable from the motor, in assembled relation therewith. Each of the brush arms 60, 61,and 62is provided with parallel extending ears 60 and 60", which are provided with apertures for receiving a non-conducting bushing 64 which is pivotally mounted on stud 63, carried by bracket 35. Coil spring 65 surrounds bushing 64 and one end of said spring bears against a brush arm and the other end of said spring is secured to a stud 66 carried by bracket 35.

Referring"to Fig. 6 the brush arms are each provided with parallel extending ears 60 and 60 between which spacers 67 are located. Each spacer is held in position by a stud 68 passing through said ears and Spacer. Studs 68 on arms 60, 61, and 62 rotatably carry non-conducting rollers 69, 69 and 69". The brush arms are provided with semi-cylindrical portions 70, which are adapted to receive the cylindrical commutator brushes 71, 72 and 73, respectively. Caps 74 attached to the brush arms by screws 75, are provided with semi-cylindrical portions 76 for engaging brushes to clamp the same to the brush arms.

M otor stopping swi ch.

Brush 73, which serves as a motor switch for starting or stoppingthe motor, is adapted to be moved into and out of engagement with the commutator 52 by a lever 80 which is pivotally mounted on a stud 81 carried by bracket 35. The inner end of lever 80 is provided with a camming surface 82 and a notch 83. When lever 80 is moved in a clockwise direction, the camming surface 82 enages roller 69 carried by brush arm 62, t ereby lifting brush 73 from the commutator 52. Upon further movement of lever. 80, the roller 69 rides into the notch 83 and brush 7 3 is held out of engagement with the commutator 52 until the lever 80 is returned to the position shown in Fig. 5.

' Bracket 35 is provided with slots 85 and 86 which receive insulating bushings 87 and 87, respectively. Brush leads 88 and 89 extend through bushing 87 and are soldered to clips 90 attached to brush arms 61 and 62, respectively, by screws 91. Brush lead 91 extends through bushing 87 and is soldered to clip 92 attached to brush arm 60 by screw 93.

Gantrol apparatus for the reversing mec ism.

The mechanism for moving the brushes 71 and 72 with respect to commutator 52 to effect reversa-lof the motor includes a rotatable shaft which extends from the' with cammingsurfaces 103 and 104 ada ted to engage the rollers 69 and 69 carrie by brush arms 60 and 61. Cam 102 is provided with curved notches 105 and 106 which are adapted alternately to receive rollers 69 and 69*, respectively.

Thereversing mechanism operates reliably with changing lengths of brushes. The- The trip mechanism for oscillating shaft 100 and cam 102, whereby alternately to raise and lower brushes 71 and 72 with respect to the commutator, is located within the gear housing 21 in order to receive lubrication from oil splashed in the gear housing 21. This mechanism includes a lost motion member 110, see Figs. 4 and '8, which is secured to the lower end of shaft 100 by a screw 111. Member-110 is provided with lugs 112 and 113 located at opposite ends of acurved edge 114. A trip member 115 is loosely journalled on shaft 100 adjacent member 110 and is held in position by a spacer 116 which is located adjacent a wall of the housing- 21. Member 115 includes a trip pawl 120 adapted to be engaged alternately by the opposite ends of a trip pad 57 carried by worm gear 57. Pawl 120 carries a stud 121 which is adapted to move around surface 114 of lost motion member 110 and to engage lugs 112 and 113 thereof. Member 115includes an acorn shaped trip cam 125 having camming surfaces 126 and 127 which, with lugs 128 and 129, respectively, define notches 130 and 131 respectively. The surfaces 126 and 127 meet at a point 182. l

The retaining pawl mechanism which is adapted for co-operation with the cam 125 of pawl 115, is carried by cover 45 and removable from the gear housing 21 with the cover 45in assembled relation, and includes an arm which is pivotally mounted on a stud 141 carried by cover 45. A set screw 142 prevents the stud 141 from turning. The free end of arm 140 extends adjacent the trip cam 125 and carries a roller 143. A coil spring 144 surrounds the stud 141, one end thereof bearing against the inner face of cover 45, and the other end hooked over the edge of arm 140, whereby yieldingly to maintain roller 143 in engagement with the camming surfaces 126 or 127.

M ode of operation.

Assuming that the brushes 71 and 72 and the reversing mechanism are ,in the positions shown in Figs. 4 and 5, to start the motor, the lever 80 is moved in a counterclockwlse direction to the posltion shown (not shown) through wire 89, brush 73,v

in Fig. 5 whereby to cause the roller 6910a brush arm 62 to be disengaged from notch 83 and. cammin surface 82 on lever 80. Spring'65 will t en move brush 73 into engagement with the commutator 52 whereby to close the motor circuit which then is as follows: from a suitable source of current will engage surface 120 of the pawl 120 in a counterclockwise direction to, the posi causing the trip member 115 to be rotated tion shown in Fig. 8. 'Upon rotation of member 115, stud 121 will move over surface 114 of member 110 and engage lug 113. At

this time the point 132 will have been moved past the roller 143, and to the right thereof as viewed in Fig. 4, so that the roller 143 has been moved over the oint 132 and has engaged surface 126. At t is time the oint 132 has moved 8 to 10 degrees co'unterc ockwise from its mid-position. The movement of roller 143.causes lever 140 to move to store power in sprin 144. It is important I to note that at this instant the brushes 71 lifting positions.

and 72 are still in the positions shown in Fig. 5, because the lost motion member 110 has not been moved from the position shown in Fig. 4. a

After the roller 143 moves past the point 132, the energy stored in spring 144 Wlll. be released whereb the trip member 115 will be actuated by t e camming action produced by pressure of roller 143 u on the surface 126. Due to engagement 0 stud 121 with lug 113, the brush cam 102 will be moved from the osition shown in Fig. 5 to that shown in ig. 7. The spring 144 is strong enough to overcome the springs and will move the brush lifting cam 102 all but about 10 degrees from either of its final brushthe speed of rotation of the motor, the spring 144, after once released, Wlll impart sufiicient momentum to the parts 125, 110, 100 and 102, to cause the brush lifting cam 102 to travel this last 10 degrees of its movement so that roller 69 of arm 61 will be received by the notch 106 of cam 102. After roller 69 of arm 60 is released from notch 105 of cam 102, the spring 65 of arm 60 causes the roller 69 to push against the cam 102 to assist its motion in a counterclockwise direction to complete the said 10 degrees movement. The shape and position of the notches .105 and 106 are such, with respect to the cooperating rollers 69 and 69 that the rollers will be retained by the However, regardless of away from the communotches until the cam 102 moves again to,

cam102. Therefore reversal of the motor is independent of the speed of the motor. If the motor power is sufficient to wind up and release the spring 144, reversal of rotation will be effected. But if the motor should stall bfore s rin position .ofms es 71 and 72 will not be changed. After the cause of the stalling hasv been removed, the motor reversing mechanism will continue its.c ole. of operation. Althou h the speed of the motor is relae tively s ow, brush reversing mechanism will operate independently of the o eration of the motor, when once-the l'nec anism has been started into operation.

This shifting of brushes 71 and 72 with respect to the commutator 52 will cause a reversal of rotation of the motor, and the circuit'will be as follows: from the source of current, through wire 89, brush 73, across the motor armature 51, brush 71',"wire 91,

field winding 50" which is ofop osite magnetic effect to field 50*, wire 50, ack to the source of current.

Upon reversal of direction of rotation o 144 is released, then the the motor, the trip pad 57 will .be rotated I in the direction of arrow 3 in Fig. 8 whereupon end '57'of pad 57 will engage surface 120 of pawl 120. Trip member will then be moved in a clockwise direction of rotation (as viewed in Fig. 8), and stud 1.21

will be moved away from lug 113 on member 1.10, and ride oversurface 114 and engage lug 112. At this instant, the point 132 will have moved to the left (as viewed in Fig. 8) of the center line joining the axes of roller 143 and shaft 100 so that roller 143 engages the surface 127 of cam 125: Thereupon spring 144 will cause roller 143 to quickly ride over surface 127 and into notch 129. This will cause, by the engagement of stud 121 with lug 112, the rotation of member 110, shaft 100'and cam 102. The cam 102 will be moved from the position shown in Fig. 7 to that shown in Fig. 5, whereby to permit brush 72 to engage the commutator, 52 and to lift brush '71 out of engagement therewith for causing reversal of the motor. The raisingof brush 71 is caused by surface 104 of cam 102 engaging roller 69, carried by brush arm 60 and roller 69 is received by notch 105 for holding brush 71 in disengaged position. A

The trip member 115 and trip pad 57 are Worm gear 57 and trip pad 57, carried thereby, dip into the lubricant Within the gear housing 21 and supply sufi'icient lubricant to the trip pawl 115 and the retaining pawl mechanism. The location of the trip mechanism and gear connections in the gear housing 21 which is remote from the field windings of the motor. reduces the liability of lubricant coming in contact with said windings and tends to reduce noise of operation.

Goaling apparatus;

The means for cooling the motor and motor mechanism includes a fan 160 located in spaced relation between the brush rigging,

mounted on the ring 35, and the motor cover 40. Fan 160 is provided with a cup-shaped central portion 161 which is provided with slots adapted to receive fingers 165 of driving dog 163.

A plate 162 of insulating material is mounted on the under side of fan portion 161 and is provided with slots to receive fingers 165. Dog 163 and plate 162 are riveted to fan portion 161 by a hollow rivet 168. A groove 169 is provided in the.com-

mutator to receive the fingers 165. The commutator end ofthe shaft 53 is provided with a tap hole adapted to receive a screw 16.4 with which the fan 160 and driving dog. is clamped to the motor rotor. The driving dog fingers 165 and groove 169 in commutator 52 provide a driving connection for the fan 160. The plate 162 prevents the are, which may be caused at the brush, from entering the upper part of the motor. Fan

blades 166 are formed by piercing the metal.

- on three sides and then bending portions 166 downwardly. These blades 166 are disposed at substantially right angles to the plane of the brush supporting bracket 35 so that the fan 160 will whirl the air substantially the same when operated in one direction as when-operated in the opposite direction. The frame 22 is provided with openings 167 through which the fan 160, upon operation, tends to draw air. The air which is drawn in through openings 167 is carried through the motor field frame and through the opening in bracket 35 adjacent the commutator. The air is whirled by the fan' in the cover 40 and deflected by the flaring skirt portion 42 down onto the ring 35" and through the annular openin 42 be tween the edge of ring 35 and sk1rt42, to the outside.

While the form of embodiment-of the 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 I claim isas' follows:

' 1. In a motor and control therefor, in com- 2. In a motor and control therefor, in combination, a stator; a rotor; a housing for the stator and rotor; an oil reservoir; a motor reversing mechanism contained by the housing and having an actuating member extending within the reservoir; and control apparatus for the reversing mechanism located within the oil reservoir and including a means operated by the rotor and a second means operatively connected with said memher and set into motion by operation of the first means and then operative independently of the first means after a predetermined movement thereof.

3. In a unitary motor and control therefor, in combination, a housing providing a gear chamber and a field frame; a partition between the gear chamber and frame; a rotor located within the field frame and having a shaft extending into the gear chamber; a motor reversing mechanism located adjacent the field frame and having an actuating member extending through the partition into said gear chamber; and control apparatus located within the gear chamber including means actuated by said rotor and a second means operatively connected with said actuating member for actuating same and adapted to be set in motion by said first means and operative independently of said first means after a predetermined movement thereof. e

4. In a unitary motor and control therefor, in combination, a housing providing a gear chamber and a motor frame; a partition between the gear chamber and frame;

a rotor located within the frame and having a shaft extending into the gear chamber; a motor reversing mechanism located within the frame and having an actuating member extending through the partition into said gear chamber; and apparatus located within the gear chamber including means actuated by said rotor and a second means connected with said actuating member for actuating same and adapted to be set in motion by said first means and operative independently of said first means after a predetermined movement thereof.

5. In a motor and control therefor, in combination, a. motor having a stator including a plurality of field windings; a rotor; commutator brushes each so connected with one of the field windings as to produce opposite magnetic effects by contact with the motor commutator; brush control apparatus for causing said brushes alternately to engage the commutator. whereby the motor is periodically reversed, said apparatus including mechanism located remote from said motor having means actuated by said motor and a second means having connections with the brushes for actuating the same and adapted to be set in motion by the first means and operative independently of said first mechanism means after a predetermined movement thereof.

6. In a unitary motor and control therefor, in combination, a housing providing a gear chamber and a field frame, said chamber having an opening; a cover for said opening; a reversing mechanism for said motor located within the frame; means carried by the cover for actuating said mechanism; and means operated by the motor for operating said reversing mechanism actuating means.

7. In a unitary motor and control therefor, in combination, a housing providing a gear chamber and a motor frame, said chamber having an opening; a cover for said opening; a reversing mechanism for said motor located within the frame; means carried within the gear chamber and removable with the cover and adapted to actuate said mechanism; and means within the gear housing and operated by the rotor for operating said reversing mechanism actuating means.

8. In a unitarymotor and control therefor, in combination, a housing providing a gear chamber and a motor frame, said chamber having an opening; a cover for said opening; a reversing mechanism for said motor located within the frame; and control apparatus including means actuated by said rotor and a second means operatively .connected with the reversing mechanism for actuating same and adapted to be set in motion by said first means and operative independently of said first means after a predetermined movement thereof, said apparatus being located within the gear chamber and removable through said opening.

In testimony whereof I hereto aflix my signature.

RALPH L. LEE.

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