US926884A - Automatic carrier. - Google Patents

Automatic carrier. Download PDF

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US926884A
US926884A US27301705A US1905273017A US926884A US 926884 A US926884 A US 926884A US 27301705 A US27301705 A US 27301705A US 1905273017 A US1905273017 A US 1905273017A US 926884 A US926884 A US 926884A
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motor
carrier
switch
hoisting
conductor
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US27301705A
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Sam H Libby
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Sprague Electric Co
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Sprague Electric Co
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60LPROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L15/00Methods, circuits, or devices for controlling the traction-motor speed of electrically-propelled vehicles
    • B60L15/002Methods, circuits, or devices for controlling the traction-motor speed of electrically-propelled vehicles for control of propulsion for monorail vehicles, suspension vehicles or rack railways; for control of magnetic suspension or levitation for vehicles for propulsion purposes

Definitions

  • My invention consists in a carrier pro-, vided with a driving motor, a hoisting motor, a current-collecting device, a controlling; switch for each motor adapted to connect f it to said device, a hei ht-limit device adapted to be actuated y the hoisting' movement, and operative connections between the height-limit device and both switches so that the hoisting motor is stopped and the driving motor is started when the load reaches a predetermined height.
  • My invention further com rises means for automatically stopping an reversing the driving or traversing motor of the carrier when it has reached the limit of its travel.
  • My invention further comprises so arranging the controlling switches of the hoist as to adapt it for use in connection with the trolley system for automatic carriers,
  • my present invention in place of the magnet winding for holding the switch in position to connect the motor to the con tinuous conductor, I so arrange the connec tions between the height-limit device and the controlling switch for the traversing motor that when the device is moved the switch is shifted to connect'the motor to the continuous conductor, and I provide means at the limit, of travel for disengaging the switch from the height-limit device, so as to allow it to return to a position to connect the motor to the sectional conductor.
  • FIG. 1 shows a side elevation of an automatic carrier arranged in accordance with my invention
  • Fig. 2 shows diagrammatically the circuit connections and arrangement of the carrier and of the trolley system.
  • FIG. B represents a bucket or other receptacle suspended from the hook H, which in turn is sus ended from the hoisting drum D driven by t e hoisting motor t M is the driving or traversing motor of the carrier, and is connected through suitable speed-reducing gears G to the driving wheels of the carrier which roll on the track T, which is indicated as of the usual I-beam form.
  • C represents the controller for the motor M only the operating shaft of this controller being shown in Fig. 1.
  • the controller is pro vided with suitable ropes h and l, by Ineans of which V the controller may be moved to hoisting and lowering positions.
  • the hook shifts the arm to the position Fig. 2, in which the position of the This arm 0 is fast to the shifts the controller, to the osition shown, which is the ofi-position.
  • T ms the circuit of the motor M is brokenand the hoisting movement stopped.
  • the height-limit device 0 is connected by a link 0 to an arm e, which is loosely mounted on the shaft of the controlling switch 0 of. the traversing motor. Pivoted on the arm e is a second arm E. The two arms E and e are drawn together by tension-spring e. The arm.
  • R represents a stop placed along the line of way at the limit of travel provided with a hinged projection 1" adapted to be engaged by the arm E.
  • the arm E strikes this stop it is moved on its pivot against the tension of spring e so as to release the cam c and allow the spring F to return the switch 0 to its other position.
  • the projection r is hinged on the stop R to allow the arm E to pass under it freely when the carrier is moved in the reverse direction.
  • the condu.c@or X is of one olarity, and the other two conductors are 0 the opposite polarity.
  • the conductor X is connected to both motors through the collecting device i. If a ground return is used, this conductor would be omitted.
  • ,Of the other two conductors which are of opposite polarity to that of conductor X, one, Y, is continuous, while the other is made'up of normally unenergized insulated sections, which are indicated by the letters Z, Z Z, etc., corresponding to a plurality of stations served by the carrier.
  • a switch S S etc. which when depressed connects all the sections of the sectional conductor to the right of the station to the continuous conductor Y.
  • the stop R which, as has been ieretofore explained, engages the arm E, and. thereby releases the switch C from the height-limit device, allowing it to return to its other operative position.
  • a circuit is th en closed from section Z of the sectional conductor through trolley i through switch through armature of motor M in the reverse direction, through field of motor Mfto trolley t, to conductor X.
  • Thei'notor is thus connected to conductor Z, instead of conductor Y, and is also connected for rotation in the opposite direction.
  • the carrier consequently starts back and runs until the trolley 15 leaves section tZ and enters on section Z.
  • the circuit of the driving motor is then broken by trolley t being on the unenergized section Z and the motor stops.
  • a hoisting motor, a traversing motor, a heightdimit device, a control switch for the hoisting motor and a reversing switch for the traversing motor both of said switches controlled by said device.
  • a traversing motor In an automatic electricallydriven carrier, a traversing motor, a hoisting motor, a reversing switch in circuit with each motor, a member adapted to be engaged by the hoistin mechanism, and operative connec tions etween said member and both switches.
  • a carrier a plurality of stations, a carrier, a hoisting motor, a traversing motor, means operated by the hoisting movement for automatically stopping the hoisting motor and starting the traversing motor, means for automatically reversing the .traversing motor at a predetermined point in its travel, and means for stopping the carrier in its return movement at any one of said stations.
  • a tions an electrically-operate carrier, a hoisting motor, a traversing motor, two working conductors extending past all of said stations, one of said conductors being continuous and the other interrupted at each sta-- tion, means operated by the hoisting movement of the carrier for automatically breaking the circuit of the hoisting motor and connecting the traversing motor to the continuous conductor, means for reversing said, traversing motor at a predetermined point in its travel and connecting it t the sectional conductor, and means at eac station for energizing the sections of said conductor between said point and that station.
  • 8.1111 a carrier system, an electrically-operated carrier, a hoisting motor, a traversing motor, a reversing switch for each motor, a
  • a carrier system an electricallydriven carrier, a reversing switch for the driving motor, a spring normally holding said switch in a certain position, hoisting mechanism carried by said carrier, a height-limit device actuated by said hoisting mechanism, operative connections between said device and said switch, and means for disengaging said switchfrom said device at a predetermined point in the travel of the carrier.
  • a carrier system a plurality of stations, a carrier, a driving motor, :a hoisting mechanism carried by said earlier, a heightlimit device actuated by said hoisting -mech-. anism, means carried. by the carrier and controlled by said device for starting said driving motor, and means for automatically reversing the drivin motor at a predetermined oint in the trave or causing the return of said carrier to any one of said stations.
  • a carrier system 'a plurality of stations, an electrically-operated carrier, a controlling switch therefor, two working conductors extending past all ofthe stations, one of the conductors being continuous and the other interrupted at each station, a hoisting mechanism carried by the carrier, a heightlimit device actuated by said hoisting mechanism, operative connections between said device and said switch adapted to move said switch to connect the driving motor of the carrier to the continuous conductor, means for automatically shifting said switch to reverse the motor and to connect it to the sectional-conductor at a predetermined point in the travel of the carrler, and means at each station for energizing the sections of said conductor between said point and that station.
  • amotor-driven carrier a trolley conductor, a collecting device carried by said carrier, a switch mounted on said carrier for closing the motor circuit through said collecting device, a hoisting. mechanism carried by the carrier, a heightlimit device actuated by said hoisting mechanism, and operative connections between said limit device and said switch foroperating said switch when thehoisting mechanism reaches the u per limit of its travel independently of the position of the carrier.
  • a motor-driven carrier comprising two conductors, collecting devices carried by said carrier and engaging said. conductors, a switch switch to close the motor circuit through the other collecting device and simultaneously to reverse the motor.
  • a motor-driven carrier comprising two conductors, collecting devices carried bysaid carrier and engaging said conductors, a switch adapted to close the motor circuit through either of said devices, and a stop along the line of travel adapted to be engaged by said carrier when driven by current through one of said collecting devices and to shift said switch to disconnect the motor circuit from that collecting device and to connect it to the other.
  • a motor-driven carrier comprising two conductors, one continuous and the other sectional, passing through a plurality of stations, collecting devices carried by said carrier and engaging said conductors, a switch adapted to close the motor circuit through either of said devices, a stop along the line of way adapted to be engaged by said carrier when driven by current from said continuous conductor and to shift said switch to connect the motor circuit to the sectional conductor and simultaneously to reverse the motor, and means at each station for energizing the sections of said conductor between said stop and that station.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Control And Safety Of Cranes (AREA)
  • Carriers, Traveling Bodies, And Overhead Traveling Cranes (AREA)

Description

S. H. LIBBY. AUTOMATIC CARRIER. APPLICATION FILED AUG. 7, 1905.
Patented July 6 /nrentor': Sam .L/bb/ UNITED STATES PATENT oFFIoE.
SAM H. LIBBY, OF EAST ORANGE, NEW JERSEY, ASSIGNOR TO SPRAGUE ELECTRIC COMPANY,
A CORPORATION OF NEW JERSEY.
AUTOMATIC CARRIER.
Specification of Letters Patent.
Patented July 6, 1909.
Application filed August 7, 1905. Serial No. 273,017.
T 0 all whom it may concern:
Be it known that I, Mr H. LIBBY, a citizen of the United States, residing at East Orange, county of Essex, State of New 1 Jersey, have invented certain new and useful:
, thereby increasing the convenience and efli- 1 ciency of the carrier. I so arrange the carrier that when the operator has once started the hoisting motor to raise the load, no further attention is required on his part;l but when the load reaches a predetermined 1 height, the hoisting movement is stopped and the traversing motor is started automatically. 1
My invention consists in a carrier pro-, vided with a driving motor, a hoisting motor, a current-collecting device, a controlling; switch for each motor adapted to connect f it to said device, a hei ht-limit device adapted to be actuated y the hoisting' movement, and operative connections between the height-limit device and both switches so that the hoisting motor is stopped and the driving motor is started when the load reaches a predetermined height.
My invention further com rises means for automatically stopping an reversing the driving or traversing motor of the carrier when it has reached the limit of its travel.
My invention further comprises so arranging the controlling switches of the hoist as to adapt it for use in connection with the trolley system for automatic carriers,
disclosed in my Patent No. 816,484, March 27, 1906. In my former application I described a trolley system extending through a plurality of stations and comprising a continuous conductor and a sectional conductor, a carrier with collecting devices adapted to engage both conductors, a switch for connecting the driving motor to either collecting device, an electro-magnet for holding the switch imposition to connect the motor to the continuous conductor, at a point at the tin I The connection V106 and means shown in full lines. limit of travel of the carrier shaft of the controller for deenergizing the magnet so as to shift the switch to connect the motor to the sectional conductor, and means at the several stations for energizing the sections of the sectional conductor between that point and that station.
By my present invention, in place of the magnet winding for holding the switch in position to connect the motor to the con tinuous conductor, I so arrange the connec tions between the height-limit device and the controlling switch for the traversing motor that when the device is moved the switch is shifted to connect'the motor to the continuous conductor, and I provide means at the limit, of travel for disengaging the switch from the height-limit device, so as to allow it to return to a position to connect the motor to the sectional conductor.
My invention will best be understood by reference to the accompanying drawing, in
, whi cl 1- Figure 1 shows a side elevation of an automatic carrier arranged in accordance with my invention, and Fig. 2 shows diagrammatically the circuit connections and arrangement of the carrier and of the trolley system.
In the drawing B represents a bucket or other receptacle suspended from the hook H, which in turn is sus ended from the hoisting drum D driven by t e hoisting motor t M is the driving or traversing motor of the carrier, and is connected through suitable speed-reducing gears G to the driving wheels of the carrier which roll on the track T, which is indicated as of the usual I-beam form.
C represents the controller for the motor M only the operating shaft of this controller being shown in Fig. 1. The controller is pro vided with suitable ropes h and l, by Ineans of which V the controller may be moved to hoisting and lowering positions.
0 re resents the height-limit device which the orm shown consists of an arm extending into the path of travel of the hook H. between the height-limit dethe controlling switches is clearly shown in arm 0 when the controller C is in the hoistivrlgl position, is indicated in dotted lines.
on the load reaches a predetermined height the hook shifts the arm to the position Fig. 2, in which the position of the This arm 0 is fast to the shifts the controller, to the osition shown, which is the ofi-position. T ms, the circuit of the motor M is brokenand the hoisting movement stopped. The height-limit device 0 is connected by a link 0 to an arm e, which is loosely mounted on the shaft of the controlling switch 0 of. the traversing motor. Pivoted on the arm e is a second arm E. The two arms E and e are drawn together by tension-spring e. The arm. E consequently bears against a cam 0 which is fast to the shaft of the controller C The cam is novided with a rojection, as shown, whic in the position shown is engaged by the arm E. Consequently, the movement of the height limit device 0 has rotated the controller C from one of its operative positions to the other. The spring F tends to return the switch C to its other position when released or disengaged from the height-limit device.
R represents a stop placed along the line of way at the limit of travel provided with a hinged projection 1" adapted to be engaged by the arm E. When the arm E strikes this stop it is moved on its pivot against the tension of spring e so as to release the cam c and allow the spring F to return the switch 0 to its other position. As will be hereafter seen, this results in reversing the traversing motor so as to start it back in the reverse direction. The projection r is hinged on the stop R to allow the arm E to pass under it freely when the carrier is moved in the reverse direction.
Now, considering the trolley system for supplying the carrier, it will be seen that there are three working conductors engaged by the collecting device 9, t and :5 respectively. The condu.c@or X is of one olarity, and the other two conductors are 0 the opposite polarity. The conductor X is connected to both motors through the collecting device i. If a ground return is used, this conductor would be omitted. ,Of the other two conductors which are of opposite polarity to that of conductor X, one, Y, is continuous, while the other is made'up of normally unenergized insulated sections, which are indicated by the letters Z, Z Z, etc., corresponding to a plurality of stations served by the carrier. At eac station is placed a switch S S etc., which when depressed connects all the sections of the sectional conductor to the right of the station to the continuous conductor Y.
The operation is then as follows: assuming thatthe hoisting motor M has been operating so as to raise the load to shift the heightlimit device to the position shown in Fig. 2, the controller C has been shifted to off-position, and the controller 0 has been shifted to the position shown. A circuit is now closed from the working conductor Y through collecting device 1?, switch 0 armature of motor M switch 0, field of motor M collecting I device 29, to conductor X. The circuit of the motor M is thus closed and the motor starts, driving the carrier toward the right, as viewed in Fig. 2. The carrier continues to run untilthe point is reached at which the load is to be dumped. At this point stop G is placed, adapted to engage the bucket B and to tip it to discharge the load. At or beyond this point is placed the stop R which, as has been ieretofore explained, engages the arm E, and. thereby releases the switch C from the height-limit device, allowing it to return to its other operative position. A circuit is th en closed from section Z of the sectional conductor through trolley i through switch through armature of motor M in the reverse direction, through field of motor Mfto trolley t, to conductor X. Thei'notor is thus connected to conductor Z, instead of conductor Y, and is also connected for rotation in the opposite direction. The carrier consequently starts back and runs until the trolley 15 leaves section tZ and enters on section Z. The circuit of the driving motor is then broken by trolley t being on the unenergized section Z and the motor stops. N ow if the man at any one of the stations served by the carrier, as for instance station 3, wishes to bring the carrier to him, he depresses his switch S and holds it down. Sections Z, Z and Z of the sectional conductor are then connected to conductor Y, so that the driving motor is again energized and drives the carrier until station 3 is reached, at which point the trolley t runs on to the dead section Z and the carrier stops. The operator may now pull down on rope Z, moving the controlling switch C to lowering position, so that the bucket will be lowered to receive another load. As the bucket is lowered, the hook H moves away from the arm 0*, so that when the bucket has been filled it may again be raised by drawing down upon the rope 71.
With the carrier arranged. as above described, it is evident that no attention is required from the operator after the hoisting motor has been started. The buckets are automatically stop ed at the proper heightto be engaged by t e stop G at the limit. of
travel, and the traversing motor is started as llll soon as the load has reached the proper i height.
I do not desire to limit myself to the particular construction and arrangement of parts here shown, but aim in the t1.)p9ll(ltl claims to cover all modifications which are within the scope of my invention.
What I claim as new, and desire to secure by Letters Patent of the UnitedStatcs, is,-
1. In an automatic carrier, a driving motor therefor, hoisting mechanism carried thereby, a current-collecting device carried by the carrier, and means actuated by the hoisting mechanism for automatically connecting said driving motor to said current collecting device independently of the posi- 3. In an automatic electrically-driven carrier, a hoisting motor, a traversing motor, a heightdimit device, a control switch for the hoisting motor and a reversing switch for the traversing motor, both of said switches controlled by said device.
4. In an automatic electricallydriven carrier, a traversing motor, a hoisting motor, a reversing switch in circuit with each motor, a member adapted to be engaged by the hoistin mechanism, and operative connec tions etween said member and both switches.
5. In a carrier system, a plurality of stations, a carrier, a hoisting motor, a traversing motor, means operated by the hoisting movement for automatically stopping the hoisting motor and starting the traversing motor, means for automatically reversing the .traversing motor at a predetermined point in its travel, and means for stopping the carrier in its return movement at any one of said stations.
6. In a carrier system, a tions, an electrically-operate carrier, a hoisting motor, a traversing motor, two working conductors extending past all of said stations, one of said conductors being continuous and the other interrupted at each sta-- tion, means operated by the hoisting movement of the carrier for automatically breaking the circuit of the hoisting motor and connecting the traversing motor to the continuous conductor, means for reversing said, traversing motor at a predetermined point in its travel and connecting it t the sectional conductor, and means at eac station for energizing the sections of said conductor between said point and that station.
7. In a carrier system, an electricallyoperated carrier, a hoisting motor, a traversing motor, a reversing switch for each motor,
lurality of stameans actuated'by the hoisting movement for moving the reversing switch of the hoisting motor to off-position and'moving the reversing switch ofv the traversing motor to one operative position, and means for moving the latter reversing switch to its other operative position at a predetermined point in the-travel of the carrier.
8.1111 a carrier system, an electrically-operated carrier, a hoisting motor, a traversing motor, a reversing switch for each motor, a
heightdimit device, operative connections between said device and both switches, and i means for automatically disengaging the reversing switch of the traversing motor from said device at a predetermined point in the travel of the carrier.
9. In a carrier system, an electricallydriven carrier, a reversing switch for the driving motor, a spring normally holding said switch in a certain position, hoisting mechanism carried by said carrier, a height-limit device actuated by said hoisting mechanism, operative connections between said device and said switch, and means for disengaging said switchfrom said device at a predetermined point in the travel of the carrier.
10. In a carrier system, a plurality of stations, a carrier, a driving motor, :a hoisting mechanism carried by said earlier, a heightlimit device actuated by said hoisting -mech-. anism, means carried. by the carrier and controlled by said device for starting said driving motor, and means for automatically reversing the drivin motor at a predetermined oint in the trave or causing the return of said carrier to any one of said stations. i
11. In a carrier system, 'a plurality of stations, an electrically-operated carrier, a controlling switch therefor, two working conductors extending past all ofthe stations, one of the conductors being continuous and the other interrupted at each station, a hoisting mechanism carried by the carrier, a heightlimit device actuated by said hoisting mechanism, operative connections between said device and said switch adapted to move said switch to connect the driving motor of the carrier to the continuous conductor, means for automatically shifting said switch to reverse the motor and to connect it to the sectional-conductor at a predetermined point in the travel of the carrler, and means at each station for energizing the sections of said conductor between said point and that station.
12. In combination, amotor-driven carrier, a trolley conductor, a collecting device carried by said carrier, a switch mounted on said carrier for closing the motor circuit through said collecting device, a hoisting. mechanism carried by the carrier, a heightlimit device actuated by said hoisting mechanism, and operative connections between said limit device and said switch foroperating said switch when thehoisting mechanism reaches the u per limit of its travel independently of the position of the carrier.,
13. In combination, a motor-driven carrier, a trolley system comprising two conductors, collecting devices carried by said carrier and engaging said. conductors, a switch switch to close the motor circuit through the other collecting device and simultaneously to reverse the motor.
14. In combination, a motor-driven carrier, a trolley system comprising two conductors, collecting devices carried bysaid carrier and engaging said conductors, a switch adapted to close the motor circuit through either of said devices, and a stop along the line of travel adapted to be engaged by said carrier when driven by current through one of said collecting devices and to shift said switch to disconnect the motor circuit from that collecting device and to connect it to the other.
15. In combination, a motor-driven carrier, a trolley system comprising two conductors, one continuous and the other sectional, passing through a plurality of stations, collecting devices carried by said carrier and engaging said conductors, a switch adapted to close the motor circuit through either of said devices, a stop along the line of way adapted to be engaged by said carrier when driven by current from said continuous conductor and to shift said switch to connect the motor circuit to the sectional conductor and simultaneously to reverse the motor, and means at each station for energizing the sections of said conductor between said stop and that station.
In witness whereof, I have hereunto set my hand this second day of August, 1905.
SAM H. LIBBY. Witnesses:
ROGER H. BUTTERWORTH, A. G. SHANNON.
US27301705A 1905-08-07 1905-08-07 Automatic carrier. Expired - Lifetime US926884A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3603169A (en) * 1970-03-06 1971-09-07 Pine Tree Engineering Position control device
US3736562A (en) * 1969-11-24 1973-05-29 Ionic Int Inc Programmable electrical control system for a transport hoist

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3736562A (en) * 1969-11-24 1973-05-29 Ionic Int Inc Programmable electrical control system for a transport hoist
US3603169A (en) * 1970-03-06 1971-09-07 Pine Tree Engineering Position control device

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