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US1386002A - Controller - Google Patents

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US1386002A
US1386002A US120277A US12027716A US1386002A US 1386002 A US1386002 A US 1386002A US 120277 A US120277 A US 120277A US 12027716 A US12027716 A US 12027716A US 1386002 A US1386002 A US 1386002A
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contact members
members
contact
controller
shaft
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US120277A
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Henry D James
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Westinghouse Electric Corp
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Westinghouse Electric Corp
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H9/00Details of switching devices, not covered by groups H01H1/00 - H01H7/00
    • H01H9/30Means for extinguishing or preventing arc between current-carrying parts
    • H01H9/44Means for extinguishing or preventing arc between current-carrying parts using blow-out magnet

Definitions

  • WITNESS-ES INVENTOR UNITED STATES PATENT OFFICE.
  • y invention relates to controllers, and it has particular relation to such controllers as are emplo ed to control the direction of rotation of electric motors.
  • My invention has for one of its objects to provide a controller that is simple in arrangement and rugged in construction for controlling the circuits of electric motors.
  • a second object of my invention is to provide a controller of the character indicated above in, which a single blowout coil operates to extinguish the arcs incident to the separation of a plurality of coacting contact mem-' bers.
  • a further object of my invention is to provide a controller of the drum type in which the arcs occurring between its several coacting contact members are extinguished by magnetic fluxes the planes of which are parallel to the axis of the controller drum.
  • I provide a controller of the drum type in which the movable contact members are carried upon the radially-projecting arms of a plu-- rality of members mounted upon the drum shafts.
  • a blowout coil surrounds the drum shaft and its circuit is so controlled that it is always connected in series circuit relation with contact members that are in engagement to close an electric circuit.
  • the magnetic circuit of the blowout coil comprises the controller shaft, a plurality of ole pieces, and the air gaps between several of the coactin movable and stationary contact members. %y means of this arrangement, the blowout coil is always connected in circuit to produce magnetic fluxes for extinguishing the arcs formed by the separation of the coacting contact members to open an electric circuit.
  • Figure 1 is a side view, partially in elevation and partially in section,'of a controller constructed in accordance with my invention, parts be- -18 and 19 whic mg broken away.
  • Figs. 2, 3, 4, 5 and 6 are reduced views of certain of the members for carrying the movable contact members. Fig.
  • a controller 1 comprises a stationary supportmg caslng 2 to which are secured polygonal rods 3 and 4.
  • a row of stationary contact fingers is respectively mounted upon and insulated from each of the rods 3 and 4.
  • three contact fingers are mounted upon each of the rods, but this number may be varied as desired.
  • a pair of oppositely disposed contact fingers are.illus trated in Fig. 7 at 32 and 38; another pair are represented in Fig. 8 at 35 and 43; and another pair are indicated in Fig. 8 at 50 and 150.
  • the controller comprises, also, a rotatable drum 7 that is supported in bearings in the ends of the casing 2.
  • the drum comprises a polygonal shaft 8 of material, which shaft is surrounded by an insulating sleeve 9.
  • Six members 10,11, 12, 13, 14 and 15, of irregular shape, are provided with radially-projecting arms upon which are mounted contact members for coacting with the station-' ary. contact fingers.
  • the members 10 and 11, 12, 13 and 14 and 15 are removably positioned upon the shaft 8.
  • a divided hub portion 16- coacts with a similar hub portion 17 on member 10 to clamp the shaft 8.
  • the members 12 andl3 are respectively rovided with hub portions 1 completely surround the shaft 8.
  • the member 12, illustrated in Fig. 4, carries contact members 39,40 and 51 and the member 13, shown in Figs. 5 and 6, contact members 41 and 42.
  • the members 14 and 15 are connected to the shaft 8 in the same manner as the members 10 and 11.
  • the members 12 and 13 are maintained in adjusted position between the members 10 and 11, which are clamped together on one side and the members 14 and 15, clamped together on the other.
  • the member 14 carries a contact member 49, the member 15, twocontact members 48 ,55 section, on line VIIVII of and 148, the member 10, a contact member 52 and the member 11, contact members 33, 34 and 53 (Fig. 8).
  • each of the rows of contact members is constituted by those carried on the respective pairs of supporting members except that the member 11 is provided with an axially-extending arm 21 which projects into the-plane of the members 12 and 13 and carries the contact member 33 in the central row.
  • Themembcr 13 is also provided with a similar arm 22 which extends into alinement with the members 10 and 11 and carries the contact member 42 in the row .on the left, as viewed in Fig. 1.
  • the members 10 and 11 are mechanically and electrically connected to each other by their respective hub portions.
  • the members 14 and 15 are similarly connected in a. like manner.
  • the members 12 and 13, which have hub portions that are independent of each other, are insulated from each other by the insulating sleeve 9.
  • the members 13 and 15 are electrically connected by means of a bridging member- 23.
  • Arc shields or barriers 24, provided with suitable recesses for receiving the arms 21 and 22 and the bridging member 23, are placed between the several rows of contact members, and other are shields 24 are located.
  • the intermediate arc shields 24 are of conventional type, being severally composed of plates 240 of insulating material and an interposed flux-conducting plate 241, constituting a pole piece.
  • a series blowout coil 25 surrounds the shaft 8 and the hub portions 18 and 19 of the members 12 and 13.
  • the terminals of the blowout coil 25 are respectively connected to the members 12 and 13.
  • the hub portions 18 and 19 together, in effect, form a unitary rotatable member for supporting the blowout coil 25. Since the contact members are directly connected to the several supporting members, which are of conducting material, preferably copper, and the blowout coil is also connected directly to a pair of the supporting members, no internal connections, other than the members themselves, are necessary.
  • FIG. 8 is a diagrammatic view of the circuits ofan electric motor and a development of a controller constructed in accordance with the disclosed embodiment of my invention for controlling the circuits of the motor.
  • An'electricmotor having an armature 26, a series field magnetwinding 27 and a shunt field magnet winding 28, receives energy from a pair of conductors 29 'contact members 33 and 34, contact finger 35, coil 36, resistor 37, armature 26, contact finger 38, contact member 40, blowout coil 25, contact members 41 and 42, contact finger 43, series field-magnet winding '27 and switch 31 to the line conductor 30.
  • the coil 36 is energized to close a relay 44 to establish a shunt circuit for a field resistor 45 and thus insure a strong field for the motor in starting.
  • the resistor 37 and the coil 36 are shunted by a relay 45 when its actuating coil 46 is energized to a predetermined degree in accordance with the counter-electromotive force of the motor.
  • the motor is then accelerated by the decrease in resistance of its armature circuit and the weakening of its field.
  • the controller is adjusted to its illustrated position, Fig. 8, to complete a dynamic braking circuit for the motor which extends from one terminal of the motor armature through contact finger 38, contact members 39 and 40, blowout coil 25, contact members 41, 48 and 49, contact finger 50,- and a portion of the resistor 37 to the other terminal of the motor armature.
  • the motor armature may rotate freely by reason of its inertia alone since it is connected neither to the line nor in a local braking circuit.
  • the blowout coil 25 is energized by any current which may be conducted by arcs occurring between the contact members.
  • the magnetic circuit of the blowout coil comprises the shaft 8, the air gaps between several contact members that are separated, and the plates 241 of the two intermediate arc shields 24, the plates 241 constituting pole pieces.
  • the planes of the inagnetic fluxes are parallel to the axis of the shaft, and the arcs are extinguished by being deflected substantially at right angles to the planes of the magnetic fluxes.
  • the controller handle is actuated in the opposite or clockwise direction.
  • the motor circuit then extends from line conductor 29, through switch 31, contact finger 32', contact member 41, blowout 130 said hub P P Q W' coil 25, contact members 40, 39 and 51, contact finger 38, armature 26, resistor 37, coil 36, contact finger 35, contact members 52 and 53, contact finger 43, series field-magnet winding 27 and switch 31, to line conductor 30.
  • the members for supporting the contact members are rugged in construction and may be formed by casting or in any other suitable manner.
  • A- single blowout coil operates to extinguish the arcs formed bythe separation of the coacting contact members which are located between the pole pieces, upon the opening of the main circuits of the motor.
  • the planes of the magnetic fluxes produced by the blowout coil are parallel to the axis'of the shaft instead of at right angles thereto, as is the case in controllers of usual construction.
  • a controller a rotatable shaft, a plurality of movable contact members rotatable therewith, a plurality of stationa contact members coacting with said movab e contact members, a blowout coil surrounding said shaft and means for connectin said blowout coil and a plurality ofpairs 0 said coacting stationary and movable contact members in series.
  • a drum shaft In a controller, a drum shaft, a plurality of contact members mounted thereon, several of said contact members being provided with integral hub portions surrounding said shaft,and a single blowout coil surrounding said shaft and said hub portions, the terminals of said coil being connected to 5.
  • a drum shaft In a controller, a drum shaft, a plural members, a conductor in several of said recesses for connecting several of said contact members, and a blowout coil surrounding said shaft between said last-named contact members.
  • a rotatable drum shaft a plurality of contact members mounted thereon, a plurality of arc barriers having recesses mounted thereon between said contact members, several of said contact members extending into said recesses, and a conductor for connecting several of said contact members extending through others of said recesses.
  • a drum shaft a pair of contact members each having a hub portion rigidly mounted upon said shaft, and a single blowout coil surrounding said shaft and said hub. portions, the terminals of said coil being connected to aid hub portions.
  • a drum shaft a plurality of contact members mounted thereon, a plurality of arc barriers having recesses and mounted on said shaft between said contact members, and a" conductor in several of said recesses for connecting several of said contact members together.
  • a controller a rotatable drum shaft, a plurality of contact members rotatable therewith, and a plurality of arc barriers mounted upon said shaft between said contact members, one of said arc barriers having a recess and one of said contact members extending into said recess.

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  • Electric Propulsion And Braking For Vehicles (AREA)

Description

H. 0,. JAMES. CONTROLLER.
APPLICATION FILED SEPT. 15, 1916.
Patented Aug. 2, 1921;
2 SHEETS-SHEET l.
| \ZIE INVENTOR Henry 0; James yfiToRNEY WITNESSES:
H. D. JAMES.
comnousn. APPLICATION FILED SEPT. I5, 1916.
2 SHEETS-SHEET 2.
Off H1):
WITNESS-ES: INVENTOR UNITED STATES PATENT OFFICE.
HENRY D. JAMES, OF EDGEWOOD PARK, PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELEC'IRIO AND MANUFACTUR SYLVAN IA.
CONTROLLER.
Specification of Letters Patent.
N G COMPANY, A CORPORATION OF PENN- Patented Aug. 2, 1921.
Application filed September 15, 1916. Serial No. 120,277.
To all whom it may concern:
Be it known that I, HENRY D. JAMES, a citizen of the United States, and a resident of Edgewood Park, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Controllers, of which the following is a specification.
y invention relates to controllers, and it has particular relation to such controllers as are emplo ed to control the direction of rotation of electric motors.
My invention has for one of its objects to provide a controller that is simple in arrangement and rugged in construction for controlling the circuits of electric motors.
A second object of my invention is to provide a controller of the character indicated above in, which a single blowout coil operates to extinguish the arcs incident to the separation of a plurality of coacting contact mem-' bers.
A further object of my invention is to provide a controller of the drum type in which the arcs occurring between its several coacting contact members are extinguished by magnetic fluxes the planes of which are parallel to the axis of the controller drum.
According to the present invention, I provide a controller of the drum type in which the movable contact members are carried upon the radially-projecting arms of a plu-- rality of members mounted upon the drum shafts. A blowout coil surrounds the drum shaft and its circuit is so controlled that it is always connected in series circuit relation with contact members that are in engagement to close an electric circuit.
The magnetic circuit of the blowout coil comprises the controller shaft, a plurality of ole pieces, and the air gaps between several of the coactin movable and stationary contact members. %y means of this arrangement, the blowout coil is always connected in circuit to produce magnetic fluxes for extinguishing the arcs formed by the separation of the coacting contact members to open an electric circuit.
In the accompanying drawings, Figure 1 is a side view, partially in elevation and partially in section,'of a controller constructed in accordance with my invention, parts be- -18 and 19 whic mg broken away. Figs. 2, 3, 4, 5 and 6 are reduced views of certain of the members for carrying the movable contact members. Fig.
18 a view, in
Fig. 1. Fig. 8 1s a diagrammatic view of circuits and apparatus embodying my in vention.
Referring particularly to Figs. 1 and 7, a controller 1 comprises a stationary supportmg caslng 2 to which are secured polygonal rods 3 and 4. A row of stationary contact fingers is respectively mounted upon and insulated from each of the rods 3 and 4. In the arrangement shown, three contact fingers are mounted upon each of the rods, but this number may be varied as desired. A pair of oppositely disposed contact fingers are.illus trated in Fig. 7 at 32 and 38; another pair are represented in Fig. 8 at 35 and 43; and another pair are indicated in Fig. 8 at 50 and 150.
The controller comprises, also, a rotatable drum 7 that is supported in bearings in the ends of the casing 2. The drum comprises a polygonal shaft 8 of material, which shaft is surrounded by an insulating sleeve 9. Six members 10,11, 12, 13, 14 and 15, of irregular shape, are provided with radially-projecting arms upon which are mounted contact members for coacting with the station-' ary. contact fingers. The members 10 and 11, 12, 13 and 14 and 15 are removably positioned upon the shaft 8. p
The member ll-is shown in Figs. 2 and 3. A divided hub portion 16- coacts with a similar hub portion 17 on member 10 to clamp the shaft 8. The members 12 andl3 are respectively rovided with hub portions 1 completely surround the shaft 8. The member 12, illustrated in Fig. 4, carries contact members 39,40 and 51 and the member 13, shown in Figs. 5 and 6, contact members 41 and 42. The members 14 and 15 are connected to the shaft 8 in the same manner as the members 10 and 11. The members 12 and 13 are maintained in adjusted position between the members 10 and 11, which are clamped together on one side and the members 14 and 15, clamped together on the other.
The member 14 carries a contact member 49, the member 15, twocontact members 48 ,55 section, on line VIIVII of and 148, the member 10, a contact member 52 and the member 11, contact members 33, 34 and 53 (Fig. 8).
When the several members are assembled on the shaft 8, the contact members carried by the several arms are arranged in three rows to coact with the stationary contact members. Each of the rows of contact members is constituted by those carried on the respective pairs of supporting members except that the member 11 is provided with an axially-extending arm 21 which projects into the-plane of the members 12 and 13 and carries the contact member 33 in the central row. Themembcr 13 is also provided with a similar arm 22 which extends into alinement with the members 10 and 11 and carries the contact member 42 in the row .on the left, as viewed in Fig. 1.
The members 10 and 11 are mechanically and electrically connected to each other by their respective hub portions. The members 14 and 15 are similarly connected in a. like manner. The members 12 and 13, which have hub portions that are independent of each other, are insulated from each other by the insulating sleeve 9. The members 13 and 15 are electrically connected by means of a bridging member- 23. Arc shields or barriers 24, provided with suitable recesses for receiving the arms 21 and 22 and the bridging member 23, are placed between the several rows of contact members, and other are shields 24 are located.
between the outer rows of contact members and the casing. The intermediate arc shields 24 are of conventional type, being severally composed of plates 240 of insulating material and an interposed flux-conducting plate 241, constituting a pole piece.
A series blowout coil 25 surrounds the shaft 8 and the hub portions 18 and 19 of the members 12 and 13. The terminals of the blowout coil 25 are respectively connected to the members 12 and 13. The hub portions 18 and 19 together, in effect, form a unitary rotatable member for supporting the blowout coil 25. Since the contact members are directly connected to the several supporting members, which are of conducting material, preferably copper, and the blowout coil is also connected directly to a pair of the supporting members, no internal connections, other than the members themselves, are necessary.
Reference may now be had to Fig. 8, which is a diagrammatic view of the circuits ofan electric motor and a development of a controller constructed in accordance with the disclosed embodiment of my invention for controlling the circuits of the motor. An'electricmotor having an armature 26, a series field magnetwinding 27 and a shunt field magnet winding 28, receives energy from a pair of conductors 29 ' contact members 33 and 34, contact finger 35, coil 36, resistor 37, armature 26, contact finger 38, contact member 40, blowout coil 25, contact members 41 and 42, contact finger 43, series field-magnet winding '27 and switch 31 to the line conductor 30.
The coil 36 is energized to close a relay 44 to establish a shunt circuit for a field resistor 45 and thus insure a strong field for the motor in starting. The resistor 37 and the coil 36 are shunted by a relay 45 when its actuating coil 46 is energized to a predetermined degree in accordance with the counter-electromotive force of the motor. The motor is then accelerated by the decrease in resistance of its armature circuit and the weakening of its field.
To stop the motor, the controller is adjusted to its illustrated position, Fig. 8, to complete a dynamic braking circuit for the motor which extends from one terminal of the motor armature through contact finger 38, contact members 39 and 40, blowout coil 25, contact members 41, 48 and 49, contact finger 50,- and a portion of the resistor 37 to the other terminal of the motor armature.
" If the controller drum is adjusted to a position between the running position and the off, the motor armature may rotate freely by reason of its inertia alone since it is connected neither to the line nor in a local braking circuit.
When the controller is actuated to its off position to separate the contact fingers 32 and 35 from the respective coacting contact members 33 and 34, the blowout coil 25 is energized by any current which may be conducted by arcs occurring between the contact members. The magnetic circuit of the blowout coil comprises the shaft 8, the air gaps between several contact members that are separated, and the plates 241 of the two intermediate arc shields 24, the plates 241 constituting pole pieces. The planes of the inagnetic fluxes, as will be readily understood, are parallel to the axis of the shaft, and the arcs are extinguished by being deflected substantially at right angles to the planes of the magnetic fluxes.
To reverse the motor, the controller handle is actuated in the opposite or clockwise direction. The motor circuit then extends from line conductor 29, through switch 31, contact finger 32', contact member 41, blowout 130 said hub P P Q W' coil 25, contact members 40, 39 and 51, contact finger 38, armature 26, resistor 37, coil 36, contact finger 35, contact members 52 and 53, contact finger 43, series field-magnet winding 27 and switch 31, to line conductor 30. I
The electrical connections of the motor armature are now reversed and the motor.
rotates in the opposite direction. The operation of the system is otherwise as de scribed above in connection with the forward rotation of themotor.
It will be noted that I provide a controller having comparatively few and simple. parts. The members for supporting the contact members are rugged in construction and may be formed by casting or in any other suitable manner. A- single blowout coil operates to extinguish the arcs formed bythe separation of the coacting contact members which are located between the pole pieces, upon the opening of the main circuits of the motor. The planes of the magnetic fluxes produced by the blowout coil are parallel to the axis'of the shaft instead of at right angles thereto, as is the case in controllers of usual construction.
'I claim as my invention:
1. In a controller, the combination with aplurality of series-connected pairs of coacting stationar contact members and movable contact mem rs, of a'blowout coil connecting a plurality of said movable contact memrs and means for connecting said coil in series circuit relation with each pair of stationary and movable contact members that are in engagement. v
y 2. In a controller, a rotatable shaft, a plurality of movable contact members rotatable therewith, a plurality of stationa contact members coacting with said movab e contact members, a blowout coil surrounding said shaft and means for connectin said blowout coil and a plurality ofpairs 0 said coacting stationary and movable contact members in series.
3. In a controller, a rotatable drum shaft,
a'plurality of movable contact members rotatable therewith, a plurality of stationary contact members coacting with said movable contact members, a plurality of arc barriers mounted on said shaft between pairs of coacting contact melnberaand a blowout coil surrounding said shaft between two adjacent. arc barriers and connecting a plurality of said movable contactmembers which are located between said two are barriers.
4-. In a controller, a drum shaft, a plurality of contact members mounted thereon, several of said contact members being provided with integral hub portions surrounding said shaft,and a single blowout coil surrounding said shaft and said hub portions, the terminals of said coil being connected to 5. In a controller, a drum shaft, a plural members, a conductor in several of said recesses for connecting several of said contact members, and a blowout coil surrounding said shaft between said last-named contact members.
6. In a controller, a rotatable drum shaft, .a plurality of contact members mounted thereon, a plurality of arc barriers having recesses mounted thereon between said contact members, several of said contact members extending into said recesses, and a conductor for connecting several of said contact members extending through others of said recesses.
7. In a controller, a drum shaft, a pair of contact members each having a hub portion rigidly mounted upon said shaft, and a single blowout coil surrounding said shaft and said hub. portions, the terminals of said coil being connected to aid hub portions.
8. In a controller, a drum shaft, a plurality of contact members mounted thereon, a plurality of arc barriers having recesses and mounted on said shaft between said contact members, and a" conductor in several of said recesses for connecting several of said contact members together.
9. In a controller, a rotatable drum shaft, a plurality of contact members rotatable therewith, and a plurality of arc barriers mounted upon said shaft between said contact members, one of said arc barriers having a recess and one of said contact members extending into said recess.
10. The combination with a plurality of stationary contact members and a plurality of forwardly and backwardly movable contact members for coacting with said stationary contact members, of a blowout coil comprising a single unit connecting a plurality of said movable contact members, and means for connecting said coil in series-circuit relation with a plurality of pairs of said stationary and movable contact members upon said movable contact members being moved either forwardly or backwardly into engagement with said stationary contact members.
11. In a controller for an electric motor having a circuit adapted to be energized by 1 I said motor, the combination with stationary and movable contact members for control ling .saidcircuit and the circuit of said motor, of a common blowout, coil for said contact members andmeans for connecting said coil in series-circuit relation with the contact members which control said circuit andwith the contact members which control the circuit of said motor. I v 12. In a controll'erfor an electric motor having a circuitadapted to be energized by said motor and. a yn ic-braking circuit,
the. combination with stationary and movable contact members for controlling said circuits, and the circuit of said motor, of a common blowout coil for said contact members and means for connecting said coil in series-circuit relation with the contact members which control the circuit of said motor, with the contact members which control said motor-energized circuit and with the contact members which control said dynamicbraking circuit. 7
In testimony whereof, I have hereunto subscribed my name this 25th day of August 1916.
HENRY n JAMES.
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