US1492796A - Short-circuiting device - Google Patents

Short-circuiting device Download PDF

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US1492796A
US1492796A US468705A US46870521A US1492796A US 1492796 A US1492796 A US 1492796A US 468705 A US468705 A US 468705A US 46870521 A US46870521 A US 46870521A US 1492796 A US1492796 A US 1492796A
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disk
contact members
contact
commutator
short
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US468705A
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Walter H Himes
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CBS Corp
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Westinghouse Electric Corp
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K27/00—AC commutator motors or generators having mechanical commutator
    • H02K27/04—AC commutator motors or generators having mechanical commutator having single-phase operation in series or shunt connection
    • H02K27/10—AC commutator motors or generators having mechanical commutator having single-phase operation in series or shunt connection with switching devices for different modes of operation, e.g. repulsion-induction motor

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  • My invention v relates to centrifugally actuated short-circuiting devices for dynamoelectric machines and it has articular relation to single-phase motors o the commutator type that are adapted for repulsion operation during the startin operation and for induction operation, a ter a predetermined s d has been attained.
  • One o ject of my invention is to provide simple, effective and inexpensive centrifugally actuated means for operatin a shortcircuiting device of the above esignated character.
  • Another object of my invention is to provide a centrifugally actuated device provided with a single-weight member so arranged as to be balanced when in its outermost position.
  • Another object of my invention is to pro y vide contact mechanism -of a satisfactory y type that shall be adapted to be mounted adjacent to the commutator cylinder, whereby certain segments thereof may be short-circuited.
  • a still further object of m invention is to provide a mechanism where y the pressure exerted by the shortcircuiting means upon the co-operating contact members shall be maintained substantially constant, irres tive of the speedl of the machine, and s all be of suicient force to insure a good contact therebetween.
  • ⁇ My present invention differs from thc arrangements previously described n that a disk of insulating'- material is provided with spaced conducting members imbedded therein which are connected together electrically by an annular conducting member which is wit moved, either circumferentially only or longitudinally only, when the machine attains a redetermined speed. Means are provided wA ereby the ressure on the disk remains constant at al times, thus insuring that a good contact shall be made between the short-circuiting member and the imbedded contact members.
  • Figure 1 is a side view. partially in elevation and partially in section, of a commutator cylinder provided with a short-circuiting device constructed in accordance with my invention.
  • Fig. 2 is an end elevation of the structure shown in Fig. 1, illustrating the centrifugally-actuated weight device employed therein.
  • Fig. 3 is an end elevational detail view of the rotatable short-circuiting disk as emplo 'ed in a device constructed in accordance my invention.
  • Fig. 4 is a cross-sectional view of a rotor of a dynamo-electric machine illustrating another form which my invention may as modified form of my invention.
  • a commutator cylinde'r 6 comprising a plurality of insulated circumferentially disposed conducting seg ments 7 arrangedu n, but insulated from, a oentrall dispose supporting member 8.
  • the mem r 8 is, in turn,v mounted upon a shalt 9.
  • a disk 10 com- 1 of insulating material in which are imbedded a plurality of contact members 11.
  • the Vcontact members 11 are each ⁇ - provided with an inte al' proection 12 of reduced cross-sectiona area w ich extends into, and is electrically and mechanically connected to, one of the commutator segments 7.
  • the outer surfaces 13 of the members 11 are referably flush with the outer surface o the disk 10.
  • the contact members 11 arezpreferably of the ordinary screw type having ay .threaded body portion 12 of reduced cross-sectional area and a head adapted to be countersunk in an opening provided therefor in the disk 10.
  • the members 11 may, however, consist of ','ns or rivets having relatively large headsl and bodies of reduced cross-sectional m88- Fig. 5 ⁇ is a cross-sectional view of another
  • a disk 14, composed of conducting material is rotatably mounted upon the supporting member 8 by means of studs or bolts 15 which extend through arcuate slots 16 in said disk.
  • the disk 14 is also provided with aplurality of spaced resilient contact fingers 17 which are adapted to engage'the outer surfaces 13 of the contact members 11 upon being rotated to a suitable position.
  • the disk 14 is also provided With an axially projecting pin 18, the purpose of which will hereinafter be set forth.
  • the disk 20 is mounted upon the shaft 9 to rotate therewith and is provided with a single centrifugally actuated member 21 piv otally mounted thereon by means of a pin 22.
  • the member 21 is provided with a'weighted portion 23 and the other end 24 is attached to a tension spring 25, the opposite end of which is attached to a pin 26 mounted on the disk 20.
  • the member 21 is also provided with an integral offset portion 2i' disposed intermediate its ends having inwardly bent fianges 28 which engage the end of the pin 18 which is mounted on the disk 14.
  • the pin 18 extendsvthrough an arcnate slot 29 in the disk 20.
  • the operation of the device is as follows: when the machine is in its starting position ⁇ the weight member 23 is in its full-line position, as shown in Fig. 2, and the short-circuiting disk 14 is in the position shown in Fig. 1, that is, with the contact fingers out of engagementI with the contact members 11.
  • the Weight member 21 moves to the position shown in dotted lines in Fig. 2, thus causing the flanges 28 of the portion 2T which engage the pin 18, to rotate the disl: 14 to bring the contact fingers 17 into engagement with the contact members 11.
  • the disk 14 moves in a circumferential direction only, and the resilient mem- ⁇ sers 17 are alike, the latter bear upon the disk 10 with equal pressure. Also, the fact that the surfaces 13 of the contact members 11 are flush with the surface of the disk ensures maintenance of constant. pressure, even when the contact fingers 1T slide upon such contact faces.
  • the armature is so balanced that, when the Weight 23 is in its innermost or starting position, the rotor is slightly unbalanced. but, when the latter attains a predetermined speed and the weight moves to its outermost position, a balanced condition is attained.
  • a disk 30 is mounted upon a supporting member 3l which, in turn, is mounted upon the shaft of the machine at the opposite end from the commutator cylinder 32.
  • the disk 31 is ,rovided with s aced contact members 33 W lich are electrica ly connected to certain of the commutator segments, or to other portions of the windings of the rotor, by means of connections 34.
  • a rotatablev disk 35 provided with contact fingers 36, serves to short circuit the contact members 33, in a manner similar to that pertaining to the device of Fig. 1.
  • a centrifugally-actuated weight member 37 similar to that described in connection with Fig. 1, serves to rotate the disk 35 when the rotor attains a predetermined speed.
  • Fig. 5 I show a commutator cylinder in which ends of conducting bars 41 project beyond the end of a centrally disposed supporting structure 42.
  • a ring 43 composed of insulating material.
  • the ring 43 is provided with a plurality of spaced contact members 44. a. portion 45 of which projects radially into openings in the ends 40 of certain of the bars 41. establishing electrical Contact therewith.
  • the head of the contact member 44 is flush with the surface of the ring 43.
  • An annular conductin" member 47 is provided with a plurality of spaced resilient conducting lingers 48 corresponding in number, to the contact members 44 and which engage the heads of the contact members 44 when the ring 47 is moved longitudinally of the commutator cylinder.
  • the member 47 may be moved 'by means of any centrifugally actuated device. not shown, that is adapted to move a short-circuiting member longitudinally with respect to the commutator cyl- I inder. ⁇
  • annular member composed of insulatingir material and mounted thereon and provided with a plurality of contact members, said contact members being electrically connected to said commntator cylinder', and a relatively movable contact element adapted to engage with said contactI members.
  • a commutator cylinder comprising a plurality of conducting segments, a body of insulating material mounted thereon and provided With a plurality of spaced contact mem-bers, said contact members being electrically connected to certain of said segments spaced about said cylinder, and a relatively rotatable member having contact brushes adapted to move in and out of engagement with said contact members.
  • anfannular member composed yo insulating material mounted thereon and proy i ments and being attached thereto, and a relatively rotatable member having short-circuited contact brushes adapted to engage said embedded contact members in one position.
  • a commutatol cylinder comprising a plurality offconductin segments, an insulating disk mounted in engagement with the end of said cylinder, said disk being provided with contact members imbedded therein, the surface of said contact members being substantially flush with the surface of said disk, each of said contact members being provided with an integral portion extending into, and attached to, one of said commutator segments, and a relatively rotatable contact element adapted to vengage with said contact members.
  • a commutator cylinder comprising a plurality of conducting segments, an insulating annular member mounted in en agement with the endof said cylinder, said annular member ybeing provided with contact members imbedded therein, the ⁇ surface of said contact members being substantially flush with the surface of said annular member.
  • each of said contact members comprising a threaded portion extending into an opening in one of said commutator segments/ and al head portion imbedded in said annular member, and a relatively rotatable short-circuiting member having brushes ada ted to move into and out of engagementc wit 7.
  • a shaft In combination, a shaft, a supporting structure thereon, a commutator cylinder mounted upon said supporting structure and comprising a plurality of conducting seg- V ments, an insulating disk mounted in lenl gagement with the end of said cylinder, said disk being provided with contact membersl imbcddeijltlierein. said contact members beingsnbstantially flush with a surface of said disk, each of said contact members bel ries said pivot pin.
  • a Speed responsive device comprising a shaft, a relatively rotatably mounted ringmember thereon and a centrifugal devicefoi' operating the same, comprising an arcuatesliaped lever-member having a pivot pin intermediate its ends and carrying an abutment pin spaced substantially radially from said pivot pin, one of said pins being carried by Said shaft and the otherby said ring-member, a weight on one end of said lever-member, a sprin having one end attached to the other end o said lever-member, and a support for the other end of said sprin said su port being carried by the saine efement w ich car- 9.
  • a rotor In a dynamo-electric machine, a rotor,
  • a commutator cylinder comprising a plurality of conducting segments, an annular member composed ot insulating material and mounted ad]acent to the end of said c i'f'linder, said annular member being provided with contact members imbedded therein, each of said contact members being provided with a reduced poradapted' ⁇ to engage said contact members iol tion vextending into, and attached to, one of members being substantially flush with the said rotatable disk by means of a pin-andsurface of said disk, a relatively rotatably slot connection.
  • centrifugally actuated weights connected to WALTER H. HIMES.

Description

May 6 1924. 1,492,796
w. H. HlMEs v SHORT CIRCUITING `DEVICE Filed May 1l 1921 2 Sheets-Sheet 1 WITNESSES: INVENTOR 7 @e man@ -v 2S 25 be K Walerffizmes,
f AT'ToRN/l/ meme Mey 6,1924.
UNITED STATES 1,492,796 PATENT OFFICE.
waarna n. xmms, or rrrrsnuaon, PENNSYLVANIA, assIoNoa 'ro wns'rmonouss annc'rmc a Kaminer om@ connu.; conroaunoa or rmmsnvnua. v
BRUIT-CIMUITING DEVICE.
Application Sled lay l1, 1031. lerjal lo. 468,705.
To all'u'lwm it may cmwern:
Be it known that I, Warmx H. Hnuzs, a citizen vof the United States, and a resident of Pittsburgh in the count of Allegheny and State o ennsylvanimlyiave invented a new and useful Improvement in Short-Circuiting Devices, of which the following is a specification.
My invention vrelates to centrifugally actuated short-circuiting devices for dynamoelectric machines and it has articular relation to single-phase motors o the commutator type that are adapted for repulsion operation during the startin operation and for induction operation, a ter a predetermined s d has been attained.
One o ject of my invention is to provide simple, effective and inexpensive centrifugally actuated means for operatin a shortcircuiting device of the above esignated character.
Another object of my invention is to provide a centrifugally actuated device provided with a single-weight member so arranged as to be balanced when in its outermost position.
Another object of my invention is to pro y vide contact mechanism -of a satisfactory y type that shall be adapted to be mounted adjacent to the commutator cylinder, whereby certain segments thereof may be short-circuited.
A still further object of m invention is to provide a mechanism where y the pressure exerted by the shortcircuiting means upon the co-operating contact members shall be maintained substantially constant, irres tive of the speedl of the machine, and s all be of suicient force to insure a good contact therebetween.
Heretofore, 't has been customary, in the construction oi short-circuiting devices for l commutators, lto move a short-circuiting member axially into en gement with the ends of the commutator ars. Construction of another type sometimes employed is that in which a disk is moved bot axially and rotatably into engagement with the ends of the commutator bars.
` My present invention differs from thc arrangements previously described n that a disk of insulating'- material is provided with spaced conducting members imbedded therein which are connected together electrically by an annular conducting member which is wit moved, either circumferentially only or longitudinally only, when the machine attains a redetermined speed. Means are provided wA ereby the ressure on the disk remains constant at al times, thus insuring that a good contact shall be made between the short-circuiting member and the imbedded contact members.
In the accompanying drawings, Figure 1 is a side view. partially in elevation and partially in section, of a commutator cylinder provided with a short-circuiting device constructed in accordance with my invention.
Fig. 2 is an end elevation of the structure shown in Fig. 1, illustrating the centrifugally-actuated weight device employed therein.
Fig. 3 is an end elevational detail view of the rotatable short-circuiting disk as emplo 'ed in a device constructed in accordance my invention.
Fig. 4 is a cross-sectional view of a rotor of a dynamo-electric machine illustrating another form which my invention may as modified form of my invention.
In the drawings, I show a commutator cylinde'r 6 comprising a plurality of insulated circumferentially disposed conducting seg ments 7 arrangedu n, but insulated from, a oentrall dispose supporting member 8. The mem r 8 is, in turn,v mounted upon a shalt 9. Upon the end `of the commutator cylinder 6 is rigidly mounted a disk 10 com- 1 of insulating material in which are imbedded a plurality of contact members 11. The Vcontact members 11 are each`- provided with an inte al' proection 12 of reduced cross-sectiona area w ich extends into, and is electrically and mechanically connected to, one of the commutator segments 7. The outer surfaces 13 of the members 11 are referably flush with the outer surface o the disk 10.
The contact members 11 arezpreferably of the ordinary screw type having ay .threaded body portion 12 of reduced cross-sectional area and a head adapted to be countersunk in an opening provided therefor in the disk 10. The members 11 may, however, consist of ','ns or rivets having relatively large headsl and bodies of reduced cross-sectional m88- Fig. 5 `is a cross-sectional view of another A disk 14, composed of conducting material is rotatably mounted upon the supporting member 8 by means of studs or bolts 15 which extend through arcuate slots 16 in said disk. The disk 14 is also provided with aplurality of spaced resilient contact fingers 17 which are adapted to engage'the outer surfaces 13 of the contact members 11 upon being rotated to a suitable position. The disk 14 is also provided With an axially projecting pin 18, the purpose of which will hereinafter be set forth.
The disk 20 is mounted upon the shaft 9 to rotate therewith and is provided with a single centrifugally actuated member 21 piv otally mounted thereon by means of a pin 22.
'One end of the member 21 is provided with a'weighted portion 23 and the other end 24 is attached to a tension spring 25, the opposite end of which is attached to a pin 26 mounted on the disk 20. The member 21 is also provided with an integral offset portion 2i' disposed intermediate its ends having inwardly bent fianges 28 which engage the end of the pin 18 which is mounted on the disk 14. The pin 18 extendsvthrough an arcnate slot 29 in the disk 20.
The operation of the device is as follows: when the machine is in its starting position` the weight member 23 is in its full-line position, as shown in Fig. 2, and the short-circuiting disk 14 is in the position shown in Fig. 1, that is, with the contact fingers out of engagementI with the contact members 11. When the machine attains a predetermined speed, the Weight member 21 moves to the position shown in dotted lines in Fig. 2, thus causing the flanges 28 of the portion 2T which engage the pin 18, to rotate the disl: 14 to bring the contact fingers 17 into engagement with the contact members 11.
Since the disk 14 moves in a circumferential direction only, and the resilient mem- `sers 17 are alike, the latter bear upon the disk 10 with equal pressure. Also, the fact that the surfaces 13 of the contact members 11 are flush with the surface of the disk ensures maintenance of constant. pressure, even when the contact fingers 1T slide upon such contact faces.
The armature is so balanced that, when the Weight 23 is in its innermost or starting position, the rotor is slightly unbalanced. but, when the latter attains a predetermined speed and the weight moves to its outermost position, a balanced condition is attained.
In the structure shown in Fig. 4, a disk 30 is mounted upon a supporting member 3l which, in turn, is mounted upon the shaft of the machine at the opposite end from the commutator cylinder 32. The disk 31 is ,rovided with s aced contact members 33 W lich are electrica ly connected to certain of the commutator segments, or to other portions of the windings of the rotor, by means of connections 34. A rotatablev disk 35, provided with contact fingers 36, serves to short circuit the contact members 33, in a manner similar to that pertaining to the device of Fig. 1. Also, a centrifugally-actuated weight member 37, similar to that described in connection with Fig. 1, serves to rotate the disk 35 when the rotor attains a predetermined speed.
Thus, it is seen that, while my structure is particularly adapted to be mounted directly upon the end of the commutator cylinder, nevertheless, it may be mounted upon the opposite end of the machine and connections made to the commutator lsegments or directly to the winding itself, as may be desired.
In Fig. 5, I show a commutator cylinder in which ends of conducting bars 41 project beyond the end of a centrally disposed supporting structure 42. Upon the inner circumference of the annular member so formed is mounted a ring 43 composed of insulating material. The ring 43 is provided with a plurality of spaced contact members 44. a. portion 45 of which projects radially into openings in the ends 40 of certain of the bars 41. establishing electrical Contact therewith. The head of the contact member 44 is flush with the surface of the ring 43. An annular conductin" member 47 is provided with a plurality of spaced resilient conducting lingers 48 corresponding in number, to the contact members 44 and which engage the heads of the contact members 44 when the ring 47 is moved longitudinally of the commutator cylinder. The member 47 may be moved 'by means of any centrifugally actuated device. not shown, that is adapted to move a short-circuiting member longitudinally with respect to the commutator cyl- I inder.`
While I have shown several embodiments of my invention` further changes and modifcations may be made without departing from the spirit. thereof. and I desire. therefore, that only 'such limitations shall be placed thereupon as areimposed by the prior art or are -specifically set forth in the. appended claims.
1 claim as my invention:
1. In combination with a commutator cylinder, an annular member composed of insulatingir material and mounted thereon and provided with a plurality of contact members, said contact members being electrically connected to said commntator cylinder', and a relatively movable contact element adapted to engage with said contactI members.
2. In combination. a commutator cylinder comprising a plurality of conducting segments, a body of insulating material mounted thereon and provided With a plurality of spaced contact mem-bers, said contact members being electrically connected to certain of said segments spaced about said cylinder, and a relatively rotatable member having contact brushes adapted to move in and out of engagement with said contact members.
3. In combination with a commutator cylinder, anfannular member composed yo insulating material mounted thereon and proy i ments and being attached thereto, and a relatively rotatable member having short-circuited contact brushes adapted to engage said embedded contact members in one position.
5. In combination, a commutatol cylinder comprising a plurality offconductin segments, an insulating disk mounted in engagement with the end of said cylinder, said disk being provided with contact members imbedded therein, the surface of said contact members being substantially flush with the surface of said disk, each of said contact members being provided with an integral portion extending into, and attached to, one of said commutator segments, and a relatively rotatable contact element adapted to vengage with said contact members.
6. In a dynamo-electric machine, a commutator cylinder comprising a plurality of conducting segments, an insulating annular member mounted in en agement with the endof said cylinder, said annular member ybeing provided with contact members imbedded therein, the `surface of said contact members being substantially flush with the surface of said annular member. each of said contact members comprising a threaded portion extending into an opening in one of said commutator segments/ and al head portion imbedded in said annular member, and a relatively rotatable short-circuiting member having brushes ada ted to move into and out of engagementc wit 7. In combination, a shaft, a supporting structure thereon, a commutator cylinder mounted upon said supporting structure and comprising a plurality of conducting seg- V ments, an insulating disk mounted in lenl gagement with the end of said cylinder, said disk being provided with contact membersl imbcddeijltlierein. said contact members beingsnbstantially flush with a surface of said disk, each of said contact members bel ries said pivot pin.
said contact members.
vided with resilient contact fingers adapted i to engage said contact members vupon rot-ation of said-last mentioned disk, said last mentioned disk being rotatably mounted uponl said commutator-cylinder-supporting structure. f
8. A Speed responsive device comprising a shaft, a relatively rotatably mounted ringmember thereon and a centrifugal devicefoi' operating the same, comprising an arcuatesliaped lever-member having a pivot pin intermediate its ends and carrying an abutment pin spaced substantially radially from said pivot pin, one of said pins being carried by Said shaft and the otherby said ring-member, a weight on one end of said lever-member, a sprin having one end attached to the other end o said lever-member, and a support for the other end of said sprin said su port being carried by the saine efement w ich car- 9. In a dynamo-electric machine, a rotor,
a disk composed of insulatingI material' mounted on said rotor, a plurality of contact members imbedded therein, the surface of said contact members being substantially flush with the surface of said disk, and means 'mounted on said rotor, a plurality' of contact members imbedded therein, the surface of said contact members being substantially flush with the surface of said disk, a second relatively rotatable disk mounted adjacent to said first mentioned disk and provided witha plurality of resilient contact fingers adapted to engage said contact members upon an ular movement of said last mentioned disk, and means for actuating said last mentioned disk when said rotor attains a predetermined speed.
' 11. In combination, a commutator cylinder comprising a plurality of conducting segments, an annular member composed ot insulating material and mounted ad]acent to the end of said c i'f'linder, said annular member being provided with contact members imbedded therein, each of said contact members being provided with a reduced poradapted'\to engage said contact members iol tion vextending into, and attached to, one of members being substantially flush with the said rotatable disk by means of a pin-andsurface of said disk, a relatively rotatably slot connection.
mounted member disposed adjacent to said In testimony whereof, I have hereunto 10 disk and provided with Contact fin ers subscribed my name this 21st day of April, adapted to engage said Contact mem rs 1921.
when said rotatable member is moved, and
centrifugally actuated weights connected to WALTER H. HIMES.
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