US1602718A - Electric control device - Google Patents

Electric control device Download PDF

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US1602718A
US1602718A US8752326A US1602718A US 1602718 A US1602718 A US 1602718A US 8752326 A US8752326 A US 8752326A US 1602718 A US1602718 A US 1602718A
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electromagnet
movement
operating
starting
running
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William C Stevens
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Cutler Hammer Manufacturing Co
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Cutler Hammer Manufacturing Co
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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
    • H02P1/00Arrangements for starting electric motors or dynamo-electric converters
    • H02P1/02Details of starting control
    • H02P1/04Means for controlling progress of starting sequence in dependence upon time or upon current, speed, or other motor parameter
    • H02P1/06Manually-operated multi-position starters
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00Machine element or mechanism
    • Y10T74/15Intermittent grip type mechanical movement
    • Y10T74/1558Grip units and features
    • Y10T74/1565Gripper releasing devices
    • Y10T74/1566Power pawl lifter
    • Y10T74/1568Automatic
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00Machine element or mechanism
    • Y10T74/15Intermittent grip type mechanical movement
    • Y10T74/1558Grip units and features
    • Y10T74/1587Grip features
    • Y10T74/1598Driven ratchet-bar and power dog
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T74/00Machine element or mechanism
    • Y10T74/18Mechanical movements
    • Y10T74/18992Reciprocating to reciprocating

Definitions

  • This invention relates to electric control devices, and, while not limited thereto, is particularly applicable to operating mechanisms for compensator starters.
  • Compensator starters are commonly arranged to establish starting connect-ions upon movement of an operating part from an intermediate off position into an extreme position and to establish running comiections upon movement of said part into an opposite extreme position.
  • the compensator is usually biased towards off position and the same is provided with a low-voltage release magnet for maintaining the running connections.
  • the present invention has among its objects to provide an improved power operating mechanism for starters of the aforesaid character.
  • Another object is to provide a power op erating mechanism of the aforesaid character having automatic means associated therewith for timing the interruption of starting connections and establishment of' running connections.
  • Figure .1 is a schematic view illustrating an embodiment of the invention.
  • Fig. 2 is a schematic view of certain of the parts shown in Fig. 1, illustrating'the same in another sition.
  • starter 1 which may be of the compensator type. As shown starter 1 is employed to establish starting and running connections for an alternating current motor M from a three phase alternating current circuit indicated by lines L L and L Starter 1 includes a control lever 2 which is adapted upon movement towards the right froman intermediate off position into an extreme position to establish starting connections and upon movement towards the left into an opposite extreme position to establish running connections. The starter is biased towards off position and is provided with a low voltage release magnet 3 for maintaining the same in running position.
  • Electromagnetic means is provided for effecting operation of starter 1, such means including a reciprocable operating member fl: and an electromagnetic winding 5 which 18 adapted upon successive responses to effect operation of said member in opposite directions.
  • Operating member is connected to the control lever 2 of the starter by a link 6 and the winding 5 is provided with a plunger 5 which is connected to an arm 7 by a link 8.
  • Arm 7 is pivoted intermediate its ends and is provided with a gear sector 9 which meshes with a gear scector 10 carried by a pivoted arm 11.
  • the upper end of arm 7 carries a pivoted latch 12 for engaging a shoulder 13 on operating member 4 while the upper end of lever 11 carries a pivoted latch 14 for engaging a shoulder 15 on said operating member.
  • Latches 12 and 14 are rovided with downwardly extending tail pieces 12 and 14 resepctively and a sliding selector bar 16 is provided for cooperation with said tail pieces to effect selective engagement and disengagement of said latches, with their respective shoulders.
  • Selector bar 16 is provided with a notch 17 for receiving the free end of tail piece 12* and a notch 18 for receiving the free end of the tailpiece 14".
  • Selector bar 16 is normally held in the position shown in Fig. 1 by a spring 19 and in such position tall piece 12 is located in notch 17 while tail piece 14 is located above the notch 18.
  • notch 17 acts to disengage latch 12 from shoulder 13 while notch 18 permits latch 14 to move into engagement with shoulder 15.
  • selector bar 16 is effected from the medium of a projection 20 on member 4 and a cam surface 21 on the lower end of selector bar 16.
  • the arrangement is such that upon movement of the o crating member 4 towards the left from t e position shown, projection 20 engages the cam surface 21 to move the selector bar 16 into its upper osition.
  • Means is provided for maintaining selector bar 16 in its upper position, such means comprising a detent 24 which is arranged to engage a notch 25 in selector bar 16 in the upper position of the latter.
  • Detent 24 is normally out of engagement with selector bar 16 and is movable into engagement therewith by an electromagnet 26.
  • Magnet 26 has a pivoted armature 27 and the detent 24 is secured to said armature by a yielding member 24.
  • Electromagnet 26 is controlled through the medium of a normally closed push button 28 and a normally open push button 29, and also through the medium of fixed contacts 30 and 31 and a cooperating bridging contact member 32 fixed to the control member 2 of starter 1. Electromagnet 26 is also provided with contacts for controlling the energizing circuit of the operating solenoid 5, such contacts including a pair of fixed contacts 33 and a cooperating bridging contact 34'fixed to the armature 27. Solenoid 5 is also controlled through the medium of a timing device 35 which includes stationary contacts 36 and a cooperating contact 37 which is normally held in engagement with said stationary contact by a spring 38.
  • Bridging contact 37 has a dash pot 39 associated therewith and as shown the piston of said dash pot is biased towards the ri ht by a spring 40.
  • the piston is provi ed with a stem which is arranged to en age the lower end of arm 7 and a collar 41 ed to said stem serves to efi'ect opening of contact 37 after a given movement of the dash pot piston towards the right.
  • depression of push button 29 establishes an energizin circuit for magnet 26 extending from line through push buttons 28 and 29 by conductor 43 to and through contacts 30, 32 and 31, by conductor 44, through the winding 26 of magnet 26 and by conductors 45 and 46 to line L.
  • responding magnet 26 establishes an energizing circuit for solenoid 5 extending from hne L throu h push button 28 by conductor 47 through the contacts 36 and 37 of the timingdevice, by conductor 48 through contacts 33 and 34, by conductor 49 to and through the solenoid 5 and by conductor 46 to line L.
  • solenoid 5 will again be energized through the medium of the. aforedes'cribed energizing circuit.
  • arms 7 and 11 are moved apart and the latch 14 associated with arm 11 acts through engage ment with shoulder 15 to move the operating member 4 towardsthe right for movement of the control member 2 of the starter from its oil to running position.
  • the starter 1 is provided with a no voltage release magnet -3 for maintaining the same in running position, and, as shown in Fig. 1, such magnet is connected across lines'L and L through the medium of push button 28.
  • bridging contact element 32 moves out of engagement with contacts 30 and 31 to interrupt the energizing circuit for magnet 26.
  • contact 34 moves out of engagement with contact 33 to interrupt the energizing circuit for solenoid 5, whereupon said solenoid 5 and the arms 7 and 11 associated therewith return to normal position.
  • the detent 24 moves out of engagement with selector bar 16 to permit the latter to return to normal position for ositioning of latches 12 and 14 as shown in ig. 1. Opening of push button 28 deenergizes the no voltage release magnet 3 to permit return of the switch control member 2 and the operating member 4 to normal position.
  • a starting device for electric motors comprising a switch member biased towards an 01f position between two extreme operative positions and operating means for said member including a power operated part having a given range of movement, said part being adapted upon successive operations in one direction through such range to move said member into said operative positions alternately.
  • a starting device for electric motors comprising a switch member. biased towards an off position between two extreme operative positions, and electromagnetic operatin means for said member including a win ing adapted upon successive responses to move said member into said operative positions alternately.
  • a starting device for electric motors comprising a switch member having a starting position, a running position and an intermediate ofl position and biased to said off position, and electromagnetic operating means for said member including a winding to be successively energized for movement of said member into said starting and running.
  • a starting device for electric motors comprising a switch member having a starting, a running and an intermediate ofi' position and biased towards said latter position, operating means for said member including a winding adapted upon successive responses to move said member from off pos tion to starting position, and then from off position to running position, and means for maintaining said winding energized for a predetermined interval upon movement of said member into its starting position.
  • a starting device for electricpmotors comprising a switch member biased to an oil position between a starting and a running position, an electromagnet for operating. said member, and means for selectively connecting said electromagnet to said operating member to provide for movement of said .-member into its starting and running positions alternately upon successive responses of said winding.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Motor And Converter Starters (AREA)

Description

Oct. 1.2 1926. 1,602,718
w. c. STEVENS INVEN TOR.
1 mm" 6.3mm
ATTORNEY Patented Oct. 12, 1926.
UNITED STATES PATENT OFFICE.
WILLIAM C. STEVENS, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO THE CUTLER-HAM- MER MFG. 00., 0F MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.
ELECTRIC CONTROL DEVICE.
Application filed February 11, 1926. Serial No. 87,523.
This invention relates to electric control devices, and, while not limited thereto, is particularly applicable to operating mechanisms for compensator starters.
Compensator starters are commonly arranged to establish starting connect-ions upon movement of an operating part from an intermediate off position into an extreme position and to establish running comiections upon movement of said part into an opposite extreme position. The compensator is usually biased towards off position and the same is provided with a low-voltage release magnet for maintaining the running connections.
The present invention has among its objects to provide an improved power operating mechanism for starters of the aforesaid character.
Another object is to provide an operating mechanism for starters of the aforesaid character including a single electromagnetic winding which is adapted upon successive responses to establish starting and running connections and to insure establishment of the former connections prior to the latter. Another object is to provide a power operating mechanism of the aforesaid character which can be readily applied to existing types of starters without changing the design thereof.
Another object is to provide a power op erating mechanism of the aforesaid character having automatic means associated therewith for timing the interruption of starting connections and establishment of' running connections.
Various other objects and advantages of the invention will hereinafter appear.
The accompanying drawing illustrates an embodiment of the invention which will now be described, it being understood that the embodiment illustrated is susceptible of modification and may be used in connection with other t pes of starters than that shown in the drawing without departing from the spirit and scope of the appended claims.
In the draw1ng.:--
Figure .1 is a schematic view illustrating an embodiment of the invention, and
Fig. 2 is a schematic view of certain of the parts shown in Fig. 1, illustrating'the same in another sition.
Referring to ig. 1, the same illustrates a starter 1 which may be of the compensator type. As shown starter 1 is employed to establish starting and running connections for an alternating current motor M from a three phase alternating current circuit indicated by lines L L and L Starter 1 includes a control lever 2 which is adapted upon movement towards the right froman intermediate off position into an extreme position to establish starting connections and upon movement towards the left into an opposite extreme position to establish running connections. The starter is biased towards off position and is provided with a low voltage release magnet 3 for maintaining the same in running position.
Electromagnetic means is provided for effecting operation of starter 1, such means including a reciprocable operating member fl: and an electromagnetic winding 5 which 18 adapted upon successive responses to effect operation of said member in opposite directions. Operating member is connected to the control lever 2 of the starter by a link 6 and the winding 5 is provided with a plunger 5 which is connected to an arm 7 by a link 8. Arm 7 is pivoted intermediate its ends and is provided with a gear sector 9 which meshes with a gear scector 10 carried by a pivoted arm 11. The upper end of arm 7 carries a pivoted latch 12 for engaging a shoulder 13 on operating member 4 while the upper end of lever 11 carries a pivoted latch 14 for engaging a shoulder 15 on said operating member. Latches 12 and 14 are rovided with downwardly extending tail pieces 12 and 14 resepctively and a sliding selector bar 16 is provided for cooperation with said tail pieces to effect selective engagement and disengagement of said latches, with their respective shoulders. Selector bar 16 is provided with a notch 17 for receiving the free end of tail piece 12* and a notch 18 for receiving the free end of the tailpiece 14". Selector bar 16 is normally held in the position shown in Fig. 1 by a spring 19 and in such position tall piece 12 is located in notch 17 while tail piece 14 is located above the notch 18. Thus upon a. given upward movement of bar 16 notch 17 acts to disengage latch 12 from shoulder 13 while notch 18 permits latch 14 to move into engagement with shoulder 15. Such upward movement of selector bar 16 is effected from the medium of a projection 20 on member 4 and a cam surface 21 on the lower end of selector bar 16. The arrangement is such that upon movement of the o crating member 4 towards the left from t e position shown, projection 20 engages the cam surface 21 to move the selector bar 16 into its upper osition. Means is provided for maintaining selector bar 16 in its upper position, such means comprising a detent 24 which is arranged to engage a notch 25 in selector bar 16 in the upper position of the latter. Detent 24 is normally out of engagement with selector bar 16 and is movable into engagement therewith by an electromagnet 26. Magnet 26 has a pivoted armature 27 and the detent 24 is secured to said armature by a yielding member 24.
Electromagnet 26 is controlled through the medium of a normally closed push button 28 and a normally open push button 29, and also through the medium of fixed contacts 30 and 31 and a cooperating bridging contact member 32 fixed to the control member 2 of starter 1. Electromagnet 26 is also provided with contacts for controlling the energizing circuit of the operating solenoid 5, such contacts including a pair of fixed contacts 33 and a cooperating bridging contact 34'fixed to the armature 27. Solenoid 5 is also controlled through the medium of a timing device 35 which includes stationary contacts 36 and a cooperating contact 37 which is normally held in engagement with said stationary contact by a spring 38. Bridging contact 37 has a dash pot 39 associated therewith and as shown the piston of said dash pot is biased towards the ri ht by a spring 40. The piston is provi ed with a stem which is arranged to en age the lower end of arm 7 and a collar 41 ed to said stem serves to efi'ect opening of contact 37 after a given movement of the dash pot piston towards the right.
The function and operation of the aforedescribed controller, together with the circuit connections therefor, will now be more fully described. Assuming that the parts are in the position shown in Fig. 1, depression of push button 29 establishes an energizin circuit for magnet 26 extending from line through push buttons 28 and 29 by conductor 43 to and through contacts 30, 32 and 31, by conductor 44, through the winding 26 of magnet 26 and by conductors 45 and 46 to line L. In responding magnet 26 establishes an energizing circuit for solenoid 5 extending from hne L throu h push button 28 by conductor 47 through the contacts 36 and 37 of the timingdevice, by conductor 48 through contacts 33 and 34, by conductor 49 to and through the solenoid 5 and by conductor 46 to line L. In responding solenoid 5 moves the arms 7 and 11 apart, and, assuming that the selector bar 16 is in the position shown, latch 12 acts through engagement with shoulder 13 to move the operating member 4 towards the left, such movement serving to move the control member 2 of the starter from its oil? into the starting position indicated in the drawing. During such movement of member 4 towards the left projection 20 acts through engagement with cam surface 21 to raise the selector bar 16 to the position shown in Fig. 2, and said bar is held in this position through engagement of detent 24 with notch 25.
Upon response of solenoid 5, the lower end of arm 7 moves out of engagement with the stem of the dash pot 39 and spring 40 then acts against the action of said dash Kit to move said stem towards the right. A r a given interval collar 41 engages the bridging contact 37 to open the same and interru t the aforcdescribed energizing circuit for so enoid 5. Starter 1 then returns to off position and the arms 7 and 11 and their associated latches 12 and 14 assume the position shown in Fig. 2, while the timing device 35 is again returned to the position shown in Fig. 1. Assuming that the push button 29 is maintained closed to maintain the aforedescribed energizing circuit for magnet 26, it is apparent that solenoid 5 will again be energized through the medium of the. aforedes'cribed energizing circuit. Upon thesecond response of solenoid 5 arms 7 and 11 are moved apart and the latch 14 associated with arm 11 acts through engage ment with shoulder 15 to move the operating member 4 towardsthe right for movement of the control member 2 of the starter from its oil to running position. As before stated, the starter 1 is provided with a no voltage release magnet -3 for maintaining the same in running position, and, as shown in Fig. 1, such magnet is connected across lines'L and L through the medium of push button 28. Upon movement of control member 2 into its running position bridging contact element 32 moves out of engagement with contacts 30 and 31 to interrupt the energizing circuit for magnet 26. Upon deenergization of said magnet, contact 34 moves out of engagement with contact 33 to interrupt the energizing circuit for solenoid 5, whereupon said solenoid 5 and the arms 7 and 11 associated therewith return to normal position. Also upon'deenergization of magnet 26 the detent 24 moves out of engagement with selector bar 16 to permit the latter to return to normal position for ositioning of latches 12 and 14 as shown in ig. 1. Opening of push button 28 deenergizes the no voltage release magnet 3 to permit return of the switch control member 2 and the operating member 4 to normal position.
What I claim and desire to secure by Letters Patent is 1. A starting device for electric motors comprising a switch member biased towards an 01f position between two extreme operative positions and operating means for said member including a power operated part having a given range of movement, said part being adapted upon successive operations in one direction through such range to move said member into said operative positions alternately.
2. A starting device for electric motors comprising a switch member. biased towards an off position between two extreme operative positions, and electromagnetic operatin means for said member including a win ing adapted upon successive responses to move said member into said operative positions alternately.
3. A starting device for electric motors comprising a switch member having a starting position, a running position and an intermediate ofl position and biased to said off position, and electromagnetic operating means for said member including a winding to be successively energized for movement of said member into said starting and running.
positions alternately.
4. A starting device for electric motors comprising a switch member having a starting, a running and an intermediate ofi' position and biased towards said latter position, operating means for said member including a winding adapted upon successive responses to move said member from off pos tion to starting position, and then from off position to running position, and means for maintaining said winding energized for a predetermined interval upon movement of said member into its starting position.
5. A starting device for electricpmotors comprising a switch member biased to an oil position between a starting and a running position, an electromagnet for operating. said member, and means for selectively connecting said electromagnet to said operating member to provide for movement of said .-member into its starting and running positions alternately upon successive responses of said winding.
6. The combination with a switch operating member having extreme starting and running positions and an intermediate off position, said member be ng biased towards said latter position, of an electromagnet having a plurality of arms associated therewith which are adapted to move in opposite directions upon response of said electromagnet, and means or alternately connecting said arms to said operating member upon succe$ive res onses of said electromagnet.
7. The com ination with a switch operating member having extreme starting and running positions, and an intermediate ofi position, of an operating electromagnet for said member, a pair of arms associated with said electromagnet and adapted to move in opposite directions upon response thereof, means "for alternately'connecting said arms to said member upon successive responses of said electromagnet to provide for movement of said operating member from off position to starting position, and then from off position to running position, and means associated with said electromagnet for maintaining the same energized for a predetermined interval upon movement of said operating member into starting position.
8. The combination with a switch operating part movable from an intermediate off position into extreme starting and running positions, said member being biased towards said off position, of an electromagnet for operating said member, a pair of pivoted arms associated with said electromagnetand adapted to move in opposite directions upon res onse thereof, a pair of latches each associated with one of said arms toponnect the latter to said operating member and a selector associated with said latches, said selector being normally in a position to effect setting of said latches for movement of said member from ofl position to starting position upon response of said winding, and being movable to another position to effect movement of said member from off position to running position upon the response of said winding, and electroma netic means associated with said selector for locking the same in its last mentioned position.
9. The combination with a switch operating part normally in a given position, an operating electromagnet therefor, means for connecting said electromagnet to said member to provide for movement of the latter in one direction out of normal position upon one response of said electromagnet and in an opposite direction out of normal position upon the next response of said electromagnet and a no volta e release magnet associated with said mem er for holding same in a given position upon dee.-.ergization of said electromagnet.
10. The combination with a switch operating member biased towards a given posi' tion and movable in opposite directions out of such position, an electromagn'et for operating said member means for connectingv said electromagnet to said member to pro vide for movement of said member into a given position upon one response of said electromagnet, and into anotherposition upon the next response of said ,electromagnet, a control device having a dash pot associated therewith for maintaining said electromagnet energized for a predetermined interval upon movement of said member in its first mentioned position and a no voltage release magnet associated with said member for holding the same in its 11st mentioned position. a
11. The combination with a switch member biased towards an intermediate off position and movable into extreme operative position, of an eiectromagnet associated with said member, means for connecting said electromagnet to said member to provide for successive movements thereof into said operative positions upon successive responses oi said winding, means for maintaining said electromagnet energized for a predetermined for effecting immediate deenergization of 15 said electromagnet upon movement of said operating member into its opposite extreme position.
In witness whereof, I have hereunto subscribed my name.
WILLIAM G. STEVENS.
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