US1522766A - Selective switch - Google Patents

Selective switch Download PDF

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Publication number
US1522766A
US1522766A US549353A US54935322A US1522766A US 1522766 A US1522766 A US 1522766A US 549353 A US549353 A US 549353A US 54935322 A US54935322 A US 54935322A US 1522766 A US1522766 A US 1522766A
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motor
circuit
contacts
switch
selector switch
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US549353A
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Gustav O Wilms
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RELIANCE Co
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RELIANCE Co
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Priority to US549353A priority Critical patent/US1522766A/en
Priority to US750163A priority patent/US1685113A/en
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    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02PCONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P7/00Arrangements for regulating or controlling the speed or torque of electric DC motors
    • H02P7/03Arrangements for regulating or controlling the speed or torque of electric DC motors for controlling the direction of rotation of DC motors

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  • This invention relates to certain new and useful improvements in mechanically operated selective Contact making and braking devices, more particularly o f that type employed in connection with magnetic switches for controlling electric circuits as, for example, circuits for reversing motors arranged for plugging or dynamic braking.
  • yThis invention as a still further object contemplates the provision of a selector switch construction operatively connected with a forward and reversin switch so that, the breaking of the circuit at either the forward or reversing switch will short circuit the armature of a direct current motor, equipped with two separate. series fields, through the proper field to thus produce a dynamic stopping effect and procure the immediate stopping of theemotor.
  • Figure 2 is a front view thereof with the parts in the positions they occupy when the left hand switch is closed and the motor operating in one direction;
  • Figure 4 is a diagrammatic view illus-- trating the various circuits.
  • arma-ture 9 The othervend of the armature is pivotally secured, by a substantially U-shaped bracketomember 1,1 and .positioned medially of the armature is a magnet coil 12 which is included in the circuity of a suitable control mechanism (not shown) such as a. shipper rod, or the like.
  • a switch Also mounted on the'other side of base 5 adjacent the upper end thereof is a switch.
  • armature 15 is pivotally secured between thesides of a substantially1 U-shaped bracket member 16, by a pin 17, a magnet coil 18 being positioned medially of the armature and adapted, upon energization, to draw, the armature theretoward, electrically connecting contacts 13 and 14.
  • the switch on vthe left side of the base is a reversing switch and the other a forward switch.
  • armatures 9 and 15 Mounted on the pivoted ends of armatures 9 and 15 are twoV inwardly projecting arms 19 and 20, respectively, arranged at substantially right angles with respect thereto with their inner ⁇ adjacent ends spaced and terminating adjacent the opposite sides ofthe hub 21 of a selector switch 22, to be later described, which is journaled on a pin or post 23 carried by base 5.
  • Extended in oppositedirections from the inner end of hub -21 are arms 34 and 35, said arms being parallel to arms 32 and 33, but back of arms 19 and 20,
  • pin 36 extends through arm 19 and makes substantially an angle of degrees 4with the face thereof and has its inner end engageable withthe upper face of arm 34 pin 10, between the sides of a and its outer face engageable with the lower face of arm 32.
  • pin 37 which is substantially identical with pin 36 and which works in connection with arms 33 and 35 in the same manner pin 36 works with respect to arms 32 and 34, and, there fore, further description thereof is deemed unnecessary.
  • a threaded stud 38 extends through a bracket 39 carried by base 5, and is locked .in any desired position of adjustin--aut by nuts 39 on either side of the bracket.
  • a spring40' has an eye-loop bent in either end, one end passing through an aperture drilled throtigh stud 38 and the other end carries a link41, the opposite end of which engages apin 42 carried by arm 24 of the selector switch near the outer end thereof.
  • Link 41 as illustrated in Figure 2, has.
  • the positive line 43 of the feed wires is electrically connected to the pivot pin or post 23 from which leads a conductor 44 to the armatureA of the motor and with contacts 7 and 8 closed, as illustrated in Figure 2, the circuit is through armature A, field 30, a conductor 45 to contact 8 through a lead 46, contact 7 and out through the negative side of the line 47. lVith the parts in this position, contacts 25 and 26 of the selector switch are in spaced relation and the force of spring 40 tends to engage saidcon-l tacts.
  • magnet coils 12 and 18 are connected with a controlling device S, which may be a manually actuated switch, or any other type of control, by a wire 48 leading to the movable contact C of the control and wires 49 and 50 leading to the fixed contacts C and C, respectively'of the controlling device, the wire 48 being connected with the line 47, the conductor 49 being connected with one side of the magnet coil 12 and the conductor 50 being connected with one side of the magnet coil 18, the othersides of the magnet coils lou being connected with the conductor 48 of the line by wires 12 and 18, respectively.
  • a controlling device S which may be a manually actuated switch, or any other type of control
  • conductors 48 and 4t are electrically connectedthrough the control mechanism S; coil 12 is energized; contacts 7 and 8 are electrically engaged and motor M operates in reverse direction.
  • lVhen conductors 48 and 49 are electrically disconnected by actuation of the control device S, coil, ⁇ 12 is deenergized and contacts 7 and 8 electrically disconnected by spring 4() and the resilient or yielding connection 51 between contact 8 and armature 9 and the sclector switch arm 24 moved to the left, with reference to Figure 2. to electrically connect contacts 25 and 2G. Vith contacts and 2G electrically connected armature A is short circuited through field 31 to dynamically brake the motor.
  • this improved switch construction is capable ot use in connection with the operation of polyphase squirrel cage motors to stop the same by plugging without in /any manner altering the principle of operation as described in connection with dynamic braking of the motor.
  • the combination in a system of motor control, of two circuit making and breaking devices means mechanically interlocking said devices whereby but one device can be operated at a time, motor actuating circuits including said devices, a motor stopping circuit, and 'a motor stopping circuit controlling means operable from the mechanically interlockeddevices to close the motor stopping circuit and procure the quick stopping of the motor when a motor actuating circuit is broken.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Stopping Of Electric Motors (AREA)

Description

G. o.v WILMs SELECTIVEl SWITCH Jan, 13. 1925 1922 2 Sheets-Sheet l Filed April 3 I N V EN TOR. quam# zfgyma.
A ORNE Y.
Jan, 13. i925. 1,522,166
v G. O. WILMS I SELECTIVE SWITCH' 4Fi ].ed April v3, 1922 2 Sheets-Sheet 2 INVENTOR.
AT ORNEY.
Patented Jan. 13, 1925.
UNITEDysTATEs PATENT OFFICE,
GUSTAV O. WILMS, OF MILWAUKEE, WISCONSIN, .ASSI-GNOR TO THE RELIANC CIOM- PAN'Y, OF MILWAUKEE, WISCONSIN, A CORPORATION'OF vWISCONSIN'.
. SELECTIVE SWITCH.
Application filed April 3,
To all whom t may cof/wem.'
yBe it known that I, GUsTAv O. WrLMs, a citizen lof the United States, and resident of Milwaukee, in the county of Milwaukeev and State of Wisconsin, havev invented new and useful Improvements in Selective Switches, of which the following is a description, reference beinghad to the accompanying drawv ings, which are a part of this specification.
This invention relates to certain new and useful improvements in mechanically operated selective Contact making and braking devices, more particularly o f that type employed in connection with magnetic switches for controlling electric circuits as, for example, circuits for reversing motors arranged for plugging or dynamic braking.
This invention has for one of its objects to provide. a selective contact making and braking device of the type described having two independent movable members mechanically interlocked to insure one being opened when the other is closed.
In the operation of polyphase squirrel cage motors controlled by magnet switches, it is often desirable to -automatically stop the motor quickly by plugging, that is, by quickly disconnecting the motor and recon nec-ting it at once to the supply line with one phase reversed, this connection being maintained until the speed diminishes to a very few revolutions per minute, or until the motor comes to rest. Ordinarily two double pole double throw magnetic switches are necessary, or two mechanical Ainterlocking magnetic switches with spring closed down contacts are required, together with a third two pole single throw magnetic switch if the motor is to be operated in both forward and reverse directions and if it is desired te stop the same quickly by plugging.
It is,'therefore, another object of this invention to accomplish the same result, be fore described, b v employing only two double pole single throw magnetic switches in which the Contact making and braking de vice serves as a mechanical interlock for the double pole switches and selects switches, together with the circuits which they control, in proper sequence, sothat as long as the forward switch is operated to start the motor, the reverse switch is selected for plugging and when the reverse switch is operated 1922. serial No. 549,353.
to start the motor, the forward switch is selected for plugging.
yThis invention as a still further object contemplates the provision of a selector switch construction operatively connected with a forward and reversin switch so that, the breaking of the circuit at either the forward or reversing switch will short circuit the armature of a direct current motor, equipped with two separate. series fields, through the proper field to thus produce a dynamic stopping effect and procure the immediate stopping of theemotor.
It is a still further object of this invention to provide a switch of the type described which may be applied to various control sys tems and which is so mechanically constructed asv to positively prevent the'closing of both the reverse and the forward switches at the same time. i
With the-above Aand other objects in View which will appear as the descriptionl proceeds, my invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described, and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the herein disclosed invention may be made as come within the scope of the claims.
In the accompanying drawings, I have illustrated one comple-te example' of the physical embodiment of my invention constructed according to the best mode I have so far devised for the practical application of y the principles thereof, and in which:
Figure 1 is a side view of a switch construction embodying my invention, a part thereof being broken away and in section to more clearly illustrate structural details;
Figure 2 is a front view thereof with the parts in the positions they occupy when the left hand switch is closed and the motor operating in one direction;
Figure 3 isa perspective view of my improved selector switch detached from the motor circuit closing switches, and
Figure 4 is a diagrammatic view illus-- trating the various circuits.
Referring now more particularly to the accompanying drawings, in which like numerals designate like parts throughout the several views, the numeral 5 designates a support base or board of suitable insulating are mounted.
material upon which the switch mechanisms Fixed on base 5, to one side and near the upper end thereof, is a standard 6 carrying on its outer end a stationary contact 7 which cooperates with a movable contact 8 on one end of an arma-ture 9. The othervend of the armature is pivotally secured, by a substantially U-shaped bracketomember 1,1 and .positioned medially of the armature is a magnet coil 12 which is included in the circuity of a suitable control mechanism (not shown) such as a. shipper rod, or the like.
Also mounted on the'other side of base 5 adjacent the upper end thereof is a switch.
construction including a supporting standard carrying'a stationary contact 13 adapted to be engaged by a movable contact 14 fixed to one end of an armature 15. The other end of armature 15 is pivotally secured between thesides of a substantially1 U-shaped bracket member 16, by a pin 17, a magnet coil 18 being positioned medially of the armature and adapted, upon energization, to draw, the armature theretoward, electrically connecting contacts 13 and 14. In the 'present illustration, the switch on vthe left side of the base is a reversing switch and the other a forward switch.
Mounted on the pivoted ends of armatures 9 and 15 are twoV inwardly projecting arms 19 and 20, respectively, arranged at substantially right angles with respect thereto with their inner` adjacent ends spaced and terminating adjacent the opposite sides ofthe hub 21 of a selector switch 22, to be later described, which is journaled on a pin or post 23 carried by base 5.
Angularly projected froln hub 2l is an arm 24, the outer end of which is bored to provide means for securementtherein of a i Contact member 25, the opposite faces of which protrude beyond the sides of the arm for selective electrical connection with spaced fixed contacts 26 and 27 connected by conductors 28 and 29, respectively', with fields 31 and 30, respectively, of a series motor M.
The selector switch may 'be moved through an angle, about pin 23f=as an axis, equal to the'distance between contacts 26 and 27, and arms 32 and 33 are formed on the outer .end of hub 21 and project in opposite directions -in front ofthe' arms 19 and 20, respectively. Extended in oppositedirections from the inner end of hub -21 are arms 34 and 35, said arms being parallel to arms 32 and 33, but back of arms 19 and 20,
respectively, and not in a vertical ,plane with arms 32 and 33.
A. pin 36 extends through arm 19 and makes substantially an angle of degrees 4with the face thereof and has its inner end engageable withthe upper face of arm 34 pin 10, between the sides of a and its outer face engageable with the lower face of arm 32. Arm 19, being made fast to armature or movable member 9, turns on pin 10 as an axis when member 9 opens and closes and the distance from the center of i the selector switch moves when pin 36 is in engagement with arm 32 and member 9 moves through anequal angle.
- Extended through arm 20 .is a pin 37 which is substantially identical with pin 36 and which works in connection with arms 33 and 35 in the same manner pin 36 works with respect to arms 32 and 34, and, there fore, further description thereof is deemed unnecessary.
A threaded stud 38 extends through a bracket 39 carried by base 5, and is locked .in any desired position of adjustin--aut by nuts 39 on either side of the bracket. A spring40'has an eye-loop bent in either end, one end passing through an aperture drilled throtigh stud 38 and the other end carries a link41, the opposite end of which engages apin 42 carried by arm 24 of the selector switch near the outer end thereof. Link 41, as illustrated in Figure 2, has. its medial portion bowed or bent to prevent interference with the movement thereof by pin 23, and spring 40 and link 4] exert a force tend- `ing to move the selector switch toward contact 26 when arm 24 is in the left half of its arc, with reference to Figure 2, and to move it toward contact 27 when the same :s in the right half of the arc.
The positive line 43 of the feed wires is electrically connected to the pivot pin or post 23 from which leads a conductor 44 to the armatureA of the motor and with contacts 7 and 8 closed, as illustrated in Figure 2, the circuit is through armature A, field 30, a conductor 45 to contact 8 through a lead 46, contact 7 and out through the negative side of the line 47. lVith the parts in this position, contacts 25 and 26 of the selector switch are in spaced relation and the force of spring 40 tends to engage saidcon-l tacts. As illustrated in the diagrammatic View, magnet coils 12 and 18 are connected with a controlling device S, which may be a manually actuated switch, or any other type of control, by a wire 48 leading to the movable contact C of the control and wires 49 and 50 leading to the fixed contacts C and C, respectively'of the controlling device, the wire 48 being connected with the line 47, the conductor 49 being connected with one side of the magnet coil 12 and the conductor 50 being connected with one side of the magnet coil 18, the othersides of the magnet coils lou being connected with the conductor 48 of the line by wires 12 and 18, respectively.
lith the parts as illustrated in Figure 2, conductors 48 and 4t) are electrically connectedthrough the control mechanism S; coil 12 is energized; contacts 7 and 8 are electrically engaged and motor M operates in reverse direction.
lVhen conductors 48 and 49 are electrically disconnected by actuation of the control device S, coil,\12 is deenergized and contacts 7 and 8 electrically disconnected by spring 4() and the resilient or yielding connection 51 between contact 8 and armature 9 and the sclector switch arm 24 moved to the left, with reference to Figure 2. to electrically connect contacts 25 and 2G. Vith contacts and 2G electrically connected armature A is short circuited through field 31 to dynamically brake the motor. This circuit is then through positive side of armature A lith the parts in the position just described, that is, both the forward and reverse switches open and contacts 25 and 26 electrically connected, an electrical connection between conductors 48 and 50 at the control mechanism, will energize coil -18 causing armature 15 to electrically engage contacts 18 and 14. The circuit is then through field 81, which is connected to the armature with its polarity reversed to that of field 30, and the motor operates in a forward direction, that is in a direction reverse to that direction when contacts 7 and 8 are electrically connected. The current lthen flows through conductor 43, post 2B, conductor 44, armature A, field 31, conductor 52` contact 14, contact 13 and then out through the negative side of the line 47. The movement of armature 15 toward its coil 18 breaks theelectric connection between contacts 25 and 26 prior to the engagement of contactsl 13 and 14, and the selector switch arm 24 is moved to the right side of its arc with contacts 25 and 27 retained in spaced relation.
Then lines 48 and 50 are electrically disconnected'by operation on the control device, contacts 13 and 14 separate and contacts 25 and 27 are electrically connected in the manner described in connection with contacts 25 and 26, and armature A then. short circuited through field 30, by conductor 45. conductor 29, y contacts 27 and 25, pivot 23 and conductor 44.
As will be readily obvious, this improved switch construction is capable ot use in connection with the operation of polyphase squirrel cage motors to stop the same by plugging without in /any manner altering the principle of operation as described in connection with dynamic braking of the motor. l
' What I claim as my invention:
1. The combination in a system of motor control, of two circuit making and breaking devices, means mechanically interlocking said devices whereby but one device can be operated at a time, motor actuating circuits including said devices, a motor stopping circuit, and 'a motor stopping circuit controlling means operable from the mechanically interlockeddevices to close the motor stopping circuit and procure the quick stopping of the motor when a motor actuating circuit is broken. 'f
2. The combination in a system of motor control, of two circuit making and breaking devices, motor actuating'circuits including said devices, means mechanically interlock ing said devices whereby but one device can be operated at a time to make a circuit, other motor circuits, and a selector switch including the said other motor actuating circuits and operable upon breaking of a motor actuating circuit at either of said devices to select one of the said other motor circuits.
3. The combination in a system of motor control, of two circuit making and breaking devices, motor actuating circuits including said devices), means mechanically interlocking said devices whereby but one device can be operated at a time to make a circuit, a motor stopping circuit, and a selector switch for closing the motor stopping circuit and operable upon breaking of a motor actuating circuit at either of said devices' to procur quick stopping of the motor. v
4. The combination in a system of motor control, of two circuit making and breaking devices, each including a movable member, an arm laterally projecting from each member, a rotatable member connecting said arms to mechanically interlock the movable members, motor actuating circuits including said devices, a motor stopping circuit, and means operable from the rotatable member and controlled by the circuit making and breaking devices to close the motor stopping circuit and quickly stop the motor upon breaking of a circuit at 'either of said devices.
5. The combination in a system of control for a motor having two field windings, of a pair of stationary contacts, circuits connecting one of said contacts -with each motor field, a movable contact engageable with either ofthe stationary contacts and electrically connected with the armature of the motor, two circuit making and breaking devices, motor actuating circuits connecting said devices with the motor whereby when one device is closed the motor is operated in one direction and when the other device is closed the motor is operated ina reverse direction, and a connection between said devices and the movable contact whereby -t-hemovable contact is engaged with one of the stationary contacts, when the motor has been operated in one direction and the Contact making and breaking device opened, to short circuit the armature through the opposite lield anddynamically brake the motor, said means being operable to engage the movable contact with the other stationary contact after the other circuit making and breaking device has been made and then broken.
6. The combination in a system of motor control, of two circuit making and breaking devices including a movable contact member, motor actuating circuits including the circuit making and breaking devices, a laterally projecting arm carried by each movable contact member', a rotatable member mounted between the adjacent ends of said arms, a connection between'said arms and rotatable member, whereby movement of one movable contact member tocircuit making osition rotates the rotatable member in one direction and a movement of the other movable contact' member to circuit making position rotates the rotatable member in a reverse direction, a motor stopping circuit, and means operable from said rotatable, member and connected with said motor stopping circuit whereby the motor is quickly stopped upon the breaking of a circuit at either of said devices.-
7. The combination in a system of motor control, of a selector switch comprising a rotatable member, an arm projecting therefrom, a movable contact carried by the outer end of said arm, a pair of stationary, con- .tacts positioned one at each en'd of the arc through which the arm moves, and motor stopping circuits including the motor and movable andstationary contacts whereby the motor is quickly stopped upon engagement of the movable contact with either of the stationary contacts.
8. The combination in a system of motor control, of two circuit making and breaking devices, each including a. movable contact member .and a stationary contact member,motor actuating circuits including the movable an'd stationary contacts of the circuit making., and breaking devices, a selector switch Vfor quickly stopping the motor connected with the 4devices and including a pair of spaced, 'stationary contacts and a movable contact operable by the movable member of the circuit making and breaking devices and adapted for selective engagement with the selector switch stationary contacts whereby the selector switch movable contact is moved toward'one selector switch stationary cont-act but held spaced-therefrom upon making of a circuit at one of said devices, Va `motor stopping circuit including the selector switch contacts, andmeans electrically tact when the circuit is broken at one of the circuit making and breaking devices.
9. The combination in a system oli' motor control, of two circuit making and breaking devices each including a movable contact member, motor actuating circuits including said circuit making and breaking devices, a motor stopping circuit, a selector "switch for closing the. motor stopping circuit to effect the quick stopping of the motor and comprising a rotatable member, a movable contact carried by the rotatable member and a'p-air of spaced, stationary contacts adapted for selective engagement by the. movable contact, a connection between the movable contact members ofthe circuit making and breaking devices and the rotatable member whereby the selector switch movable contact is moved toward one selector switch stationary contact but held spaced therefrom upon making of .al circuit at one of said devices, and means tor electrically connecting the selector switch movable contact with said adjacent selector switch stationary contact when the circuit is broken at said device.
10. The combination in a systemv of motor control, of two circuit making and breaking devices each including a movable contact member, motor actuating circuits including said circuit making and breaking devices, a motor stopping circuit, a selector switch for closing the motor stopping circuit to effect the quick stopping of the motor and comprising a pair of spaced, stationary contacts and a mov-able contact operable by the rotatable member and adapted for selective engagement with the selector switch stationary contacts, whereby the selector switch movable contact is moved toward one selector switch stationary contact but held spaced1 therefrom upon making of a circuit at one of said devices, and means for electrically connecting the selector switch movable contact with said selector switch stationary contact when the circuit is `broken at said device, the selector switch movable contact being moved toY a position adjacent theother selector switch stationary contact when a circuit is-.made at the other circuit making and breaking device and being elecvtrically lconnected 'with the other selector switch Stationarycontact when .the circuit is then broken at said othcrdevice.
In testimony whereof I afliX my signature.
GUSTAV O. WILMS.
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US750163A US1685113A (en) 1922-04-03 1924-11-15 Mechanical movement

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2446299A (en) * 1944-02-14 1948-08-03 Guardian Electric Mfg Co Interlocking relay
US2762883A (en) * 1950-11-13 1956-09-11 Gregor L Lang Force applying mechanism
DE1147299B (en) * 1958-12-11 1963-04-18 Constantino Grand Mechanical locking device for two side by side arranged electromagnets of a reversing contactor

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2446299A (en) * 1944-02-14 1948-08-03 Guardian Electric Mfg Co Interlocking relay
US2762883A (en) * 1950-11-13 1956-09-11 Gregor L Lang Force applying mechanism
DE1147299B (en) * 1958-12-11 1963-04-18 Constantino Grand Mechanical locking device for two side by side arranged electromagnets of a reversing contactor

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