US795112A - Safety device for elevators. - Google Patents

Safety device for elevators. Download PDF

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US795112A
US795112A US24518105A US1905245181A US795112A US 795112 A US795112 A US 795112A US 24518105 A US24518105 A US 24518105A US 1905245181 A US1905245181 A US 1905245181A US 795112 A US795112 A US 795112A
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cage
shaft
door
magnet
controlling
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US24518105A
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Robert H Gaylord
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66BELEVATORS; ESCALATORS OR MOVING WALKWAYS
    • B66B13/00Doors, gates, or other apparatus controlling access to, or exit from, cages or lift well landings
    • B66B13/22Operation of door or gate contacts

Definitions

  • This invention relates to a safety device adapted for electric or hydraulic elevators; and the main object of the invention is to provide a device which when the cage has been brought to a stop and the door of the landing is opened to allow passengers to get into or out of the cage automatically locks the controlling-lever, so that it is impossible to move the cage up or down while the door is open and while passengers are getting into or out of the cage, thus avoiding accidents, which are of frequent occurrence, due to the cage moving while passengers are getting into or out of it.
  • Anotherobject of the invention is to provide means for automatically notifying passengers whether the controller is locked or not, so that they may get into or out of the cage without fear when notified that the cage is safely at rest or may refrain from doing so when notified that the cage is not safely at rest.
  • Figure 1 is a vertical section through an elevator-shaft and cage.
  • Fig. 2 is a front elevation of the lower part of the controllinglever, shaft, and locking device.
  • Fig. 3 is a sectional View on line m3 m3, Fig. 2.
  • Fig. 1 is a longitudinal sectional view through a dooroperated switch, showing the adjacent part of the door in connection therewith.
  • Fig. 5 is a section on line m5 m5, Fig. 4.
  • Fig. 6 is a diagram of the wiring system.
  • Each doorswitch comprises a casing 4, having a head 5 of insulating material. Slidably mounted in both heads of the casing is a rod 6, to which is attached a block 7, of insulating material, and carrying a contact-ring 8. Attached to the head 5 are two segmental spring-contacts 9, with terminals 10 extending through the head.
  • the spring-contacts 9 normally stand out inclined from the head 5, but are of a length which when they are flattened down by the contact-ring 8 pressing them toward the head causes them to touch each other, so that the circuit is closed not only by the bridging of the spring-contacts 9 by the contact-ring 8, but also by the contact thus secured between the spring-contacts themselves.
  • a coil-spring 11 Interposed between the block 7 and the rear head of the casing 4 is a coil-spring 11, which when expanded forces the block7 toward the head 5, so that the ring 8 presses in and flattens the spring-contacts 9 against each other, as before described.
  • each door 2 at its upper corner is a bracket 12, and the door-switch 3 is so located that when the door is shut the bracket 12 presses against the end of the rod 6, contracting the spring 11 and holding the block 7 away from the head 5 with the ring 8 out of contact with the spring-fingers 9, so that the circuit therethrough is broken.
  • hangers 15 Mounted preferably underneath the floor 13 ofthe cage 14 are hangers 15, in which is journaled a shaft 16, the mechanism for operating the cage being controlled by the Shaft 16;
  • controlling-lever 17 Fastened to the shaft 16 is a controlling-lever 17, which extends up through the floor of the cage and which may be rocked across a sector 18, there being a latch 19 carried by the controlling-lever for detachably engaging the sector 18 to hold the operating-lever in its central position.
  • Carried by the shaft 16 is a sector 20, suspended by arms 21, which radiate from a hub 22, which has flanges 23 and which is rigidly attached to the shaft 16 by taper pins 24.
  • a circular magnet-box 25 having a split sleeve 26 encircling the hub 22 and lying between the ianges 23.
  • the lower end of the magnetbox has a boss 27, through one end of which a brace 28 extends, there being nuts 29 thereon for engaging both sides of the boss for adjustably holding the magnet-box in position, the other end o-f the brace 28 being fastened to the under side of the cage, as shown in Fig. 1.
  • the magnet-box 25 has a detachable cover 30, which protects the contents thereof, but which is easily removable to allow inspection of the interior.
  • the magnet-box has a boss 31, and slidably mounted therein and in the back wall of the magnet-box is a locking-bolt 32, while the sector 2O has a circular recess 33, adapted when in register with the locking-bolt to receive the same and being of a larger size than the bolt allows a limited movement of the sector when the bolt lies therein.
  • armature 35 Mounted upon the boss 31 is a magnet 34, and pivoted to the back wall of the magnetboX is an armature 35, the lower end of which lies in a recess 36 in the locking-bolt 32, the armature being normally held away from the magnet with the locking-bolt retracted by means of a fiat spring 37.
  • the upper end of the armature carries an insulated contact-blade 38, which when the armature is attracted by the magnet is forced between two spring-clips 39, thus closing a circuit therethrough.
  • a safety-indicator comprising in this embodiment a lamp 40, one terminal of which is connected by a wire 41 with one of the contact-clips 39, its other terminal being connected by a wire 42 with a wire 43, forming one side of a circuit, a wire 44 forming the other side.
  • the other contact-clip 39 is connected by a wire 45 with the wire 44, thus placing the lamp in parallel in the main circuit.
  • the door-switches on the landings, as A, B, and C, are each connect'ed in parallel in the main circuit by wires 46 and 47, which respectively connect with the wires 43 and 44.
  • the main circuit is normally open at each of the landings at the door-switches when the doors of the landings are closed, and as the magnet 34 is thus normally denergized the circuit through the lamp 4() is also normally open at the contact-clips 39.
  • the cage In operation the cage is moved up or down by throwing the controlling-lever 17 to one side or the other of the center.
  • the sector 20 lies with its recess 33 in register with the locking-bolt 32, and as soon as the door of the landing is opened the circuit through its door-switch is closed, as before explained, which energizes the magnet 34, thereby attracting the armature 35 and throwing the locking-bolt 32 into the recess 33 of the sector 30, thus automatically locking the controlling-lever 17 against movement, except for avery slight amount which is useful in cushioning with hydraulic elevators.
  • controlling-lever 17 As the controlling-lever 17 is thus locked when the landing-door is open, it prevents the operator from moving the cage up or down while passengers are getting into or out of the cage, and the controlling-lever remains thus-locked until the door is closed, whereupon the circuit being again opened the magnet 34 releases the armature 35, which is thus drawn back by its spring 37, thus retracting the locking-bolt 32 from the recess 33 of the sector.
  • an elevator-shaft for regulating the passage of passengers to and from the cage, means for automatically preventing movement of the cage when the door is open, and magnetically-operated means for indicating the condition of the last means.
  • an elevator-shaft for regulating the passage of passengers to and from the cage, means for automatically preventing movement of the cage when the door is open, and magnetically-operated means carried by the cage for indicating the condition of the last means.
  • an elevator-shaft landing-doors therefor, a cage in the shaft, means for automatically preventing movement of the cage after it has been brought to a stop and a door is open, and magnetically-operated means for indicating the condition of the last means.
  • a door for regulating the passage of passengers to and from the cage, a controller for the cage, means for locking the controller and allowing a limited movement thereof for cushioning when said door is open, and magnetically-operated means. for indicating a locked or unlocked condition of the controller.
  • an elevator-shaft landing-doors therefor, a cage in the shaft, a controller for the cage, and vmeans for automatically locking the controller when a landingdoor is open, and means for unlocking the controller when the door is shut, and magnetically-operated means for indicating a locked or unlocked condition of the controller.
  • an elevator-shaft landing-doors therefor, a cage in the shaft, a controller for the cage, a safety-indicator Yin the cage, magnetically-operated means for locking the controller and for controlling said indicator, and means operated by said doors for controlling the magnetic means.
  • an elevator shaft a cage in the shaft, a door for regulating the passage of passengers to and from the cage, a controller for the cage, a lock for the controller, a safety-indicator, a magnet for operating the lock and safety-indicator, an electric circuit through the magnet and safetyindicator, and means operated by the door for controlling the circuit.
  • an elevator-shaft landing-doors therefor, a cage in the shaft, a controller for the cage, a lock for the controller, a safety-indicator in the cage, an electric circuit through the magnet and safety-indicator,- a magnet for operating the lock and safetyindicator, and means operated by the doors for controlling the circuit.
  • an elevator-shaft a cage in the shaft, a door for regulating the passage of passengers to and from the cage, a controller for the cage, a lock for the controller allowing a limited movement of the same when locked, a magnet for operating the lock, a safety-indicator in the cage controlled by said magnet, an electric circuit through the magnet and safety-indicator and means operated by the door for controlling said circuit.
  • an elevator-shaft a cage in the shaft, a door for regulating the passage of passengers to and from the cage, a shaft carried by the cage, a controlling-lever attached to the shaft, a sector carried by the shaft, a lock for the sector, means for adjusting the lock concentrically of the sector, and means operated by the door for controlling the lock.
  • a cage In combination, a cage, a shaft carried by the cage, a controlling-lever attached to the shaft, a sector carried by the shaft, a lock for the sector, and means for adjusting the lock concentrically of the sector.
  • a cage In combination, a cage, a shaft carried thereby, a controlling-lever attached to the shaft for rocking the same, a sector carried and rocked by the shaft and having a recess, a magnet-box hung concentrically With the sector, a locking-bolt slidably mounted in the box and adapted to enter the recess in the sector, a magnet in the boX, an armature therefor connected to the locking-bolt, and means for controlling the magnet.
  • a cage In combination, a cage, a shaft carried thereby, a controlling-lever attached to the shaft, a magnet-box hung from the shaft, a sector att-ached to the -shaft and having a recess, a locking-bolt slidable in the magnetbox and adapted to enter the recess, a magnet in the box, an armature therefor connected with the locking-bolt, a circuit through the magnet, a lamp in the cage connected in parallel in the circuit, contact-clips forming terminals in the lamp-circuit, a contact-blade carried by the armature for closing the circuit through said clips, and means for controlling the iirst circuit.
  • a cage In combination, a cage, a shaft carried thereby, a hub on the shaft having arms, a sector on the arms, a magnet-box having a split sleeve around said hub, and a locking mechanism carried by the magnet-box for engaging the sector.

Description

PATBNTED JULY 18, 1905.
ssii se i@ lum` in -lm luy R. H. GAYLORD.
APPLICATION PILED FBB.11,19.05.
SAFETY DEVICE POR ELEVATORS.
,mnmtw a cmu IAM oo. "ma ummm/muni vmslmmm n. c.
UNITED STATES Patented July 18, 1905.
ROBERT H. GAYLORD, OF PASADENA, CALIFORNIA.
SAFETY DEVICE FOR ELEVATORS.
SPECIFICATION forming part of Letters Patent No. 795,112, dated July 18, 1905.
Application filed February 11, 1905. Serial No. 245,181.
To all whom, it may concern,.-
Beit known that I, ROBERT H. GAYLOED, a citizen of the United States, residing at Pasadena, in the county of Los Angeles and State of California, have invented a new and useful Safety Device for Elevators, of which the following is a specification.
This invention relates to a safety device adapted for electric or hydraulic elevators; and the main object of the invention is to provide a device which when the cage has been brought to a stop and the door of the landing is opened to allow passengers to get into or out of the cage automatically locks the controlling-lever, so that it is impossible to move the cage up or down while the door is open and while passengers are getting into or out of the cage, thus avoiding accidents, which are of frequent occurrence, due to the cage moving while passengers are getting into or out of it.
Anotherobject of the invention is to provide means for automatically notifying passengers whether the controller is locked or not, so that they may get into or out of the cage without fear when notified that the cage is safely at rest or may refrain from doing so when notified that the cage is not safely at rest.
While the invention is especially applicable for hydraulic and electric elevators, it is also adapted for use on other types of elevators.
The accompanying drawings illustrate the invention, and referring thereto- Figure 1 is a vertical section through an elevator-shaft and cage. Fig. 2 is a front elevation of the lower part of the controllinglever, shaft, and locking device. Fig. 3 is a sectional View on line m3 m3, Fig. 2. Fig. 1 is a longitudinal sectional view through a dooroperated switch, showing the adjacent part of the door in connection therewith. Fig. 5 is a section on line m5 m5, Fig. 4. Fig. 6 is a diagram of the wiring system.
1 designates the walls of the elevator-shaft, the section illustrated including two of the landings A and B. Each landing has a sliding door 2 and a door-switch 3. Each doorswitch comprises a casing 4, having a head 5 of insulating material. Slidably mounted in both heads of the casing is a rod 6, to which is attached a block 7, of insulating material, and carrying a contact-ring 8. Attached to the head 5 are two segmental spring-contacts 9, with terminals 10 extending through the head. The spring-contacts 9 normally stand out inclined from the head 5, but are of a length which when they are flattened down by the contact-ring 8 pressing them toward the head causes them to touch each other, so that the circuit is closed not only by the bridging of the spring-contacts 9 by the contact-ring 8, but also by the contact thus secured between the spring-contacts themselves. Interposed between the block 7 and the rear head of the casing 4 is a coil-spring 11, which when expanded forces the block7 toward the head 5, so that the ring 8 presses in and flattens the spring-contacts 9 against each other, as before described.
Attached to each door 2 at its upper corner is a bracket 12, and the door-switch 3 is so located that when the door is shut the bracket 12 presses against the end of the rod 6, contracting the spring 11 and holding the block 7 away from the head 5 with the ring 8 out of contact with the spring-fingers 9, so that the circuit therethrough is broken.
Mounted preferably underneath the floor 13 ofthe cage 14 are hangers 15, in which is journaled a shaft 16, the mechanism for operating the cage being controlled by the Shaft 16;
Fastened to the shaft 16 is a controlling-lever 17, which extends up through the floor of the cage and which may be rocked across a sector 18, there beinga latch 19 carried by the controlling-lever for detachably engaging the sector 18 to hold the operating-lever in its central position.
Carried by the shaft 16 is a sector 20, suspended by arms 21, which radiate from a hub 22, which has flanges 23 and which is rigidly attached to the shaft 16 by taper pins 24. Depending from the hub 22 isa circular magnet-box 25, having a split sleeve 26 encircling the hub 22 and lying between the ianges 23. The lower end of the magnetbox has a boss 27, through one end of which a brace 28 extends, there being nuts 29 thereon for engaging both sides of the boss for adjustably holding the magnet-box in position, the other end o-f the brace 28 being fastened to the under side of the cage, as shown in Fig. 1. ,By moving' the controlling-lever 17 the shaft 16 may be freely turned in the sleeve 26. The magnet-box 25 has a detachable cover 30, which protects the contents thereof, but which is easily removable to allow inspection of the interior.
rIhe bottom of the magnet-box has a boss 31, and slidably mounted therein and in the back wall of the magnet-box is a locking-bolt 32, while the sector 2O has a circular recess 33, adapted when in register with the locking-bolt to receive the same and being of a larger size than the bolt allows a limited movement of the sector when the bolt lies therein.
Mounted upon the boss 31 is a magnet 34, and pivoted to the back wall of the magnetboX is an armature 35, the lower end of which lies in a recess 36 in the locking-bolt 32, the armature being normally held away from the magnet with the locking-bolt retracted by means of a fiat spring 37. The upper end of the armature carries an insulated contact-blade 38, which when the armature is attracted by the magnet is forced between two spring-clips 39, thus closing a circuit therethrough.
Carried by the cage is a safety-indicator, comprising in this embodiment a lamp 40, one terminal of which is connected by a wire 41 with one of the contact-clips 39, its other terminal being connected by a wire 42 with a wire 43, forming one side of a circuit, a wire 44 forming the other side. The other contact-clip 39 is connected by a wire 45 with the wire 44, thus placing the lamp in parallel in the main circuit. The door-switches on the landings, as A, B, and C, are each connect'ed in parallel in the main circuit by wires 46 and 47, which respectively connect with the wires 43 and 44.
The main circuit is normally open at each of the landings at the door-switches when the doors of the landings are closed, and as the magnet 34 is thus normally denergized the circuit through the lamp 4() is also normally open at the contact-clips 39.
In operation the cage is moved up or down by throwing the controlling-lever 17 to one side or the other of the center. When the cage is brought to a stop at a landing by bringing the controlling-lever 17 to central position, the sector 20 lies with its recess 33 in register with the locking-bolt 32, and as soon as the door of the landing is opened the circuit through its door-switch is closed, as before explained, which energizes the magnet 34, thereby attracting the armature 35 and throwing the locking-bolt 32 into the recess 33 of the sector 30, thus automatically locking the controlling-lever 17 against movement, except for avery slight amount which is useful in cushioning with hydraulic elevators. As the controlling-lever 17 is thus locked when the landing-door is open, it prevents the operator from moving the cage up or down while passengers are getting into or out of the cage, and the controlling-lever remains thus-locked until the door is closed, whereupon the circuit being again opened the magnet 34 releases the armature 35, which is thus drawn back by its spring 37, thus retracting the locking-bolt 32 from the recess 33 of the sector.
Upon the locking of the controlling-lever 17 when the door of a landing is opened the lamp 40 is caused to glow by reason of the armature 35 forcing the contact-blade 38 between the spring-clips 39. Thus passengers are assured when they see the lamp burning that the cage is safely at rest and locked and may freely enter or leave the cage without apprehension of accident. It will be observed that the lamp will not glow upon the mere opening of the door, it being necessary that the locking-bolt enter the recess in the sector. If the door should be opened while the controlling-lever stood at either side of its central position and was thus unlocked, the lamp would not burn and passengers would not then venture to get into or out of the cage even though it was moving very slowly, as they would know that while they were getting in or out the cage might take a sudden start. There is thus a double check against -accidentsethe absolute locking of the controlling-lever when it is in central position and the landing-door open and the notification to passengers that the lever is or is not locked.
What I claim is- 1. In combination, an elevator-shaft, landing-doors therefor, a cage in the shaft, a controller for the cage, means for automatically locking the controller when a landing-door is open, and magnetically-operated means for indicating a locked or unlocked condition of the controller.
2. In combination, an elevator-shaft, acage, a door for regulating the passage of passengers to and from the cage, means for automatically preventing movement of the cage when the door is open, and magnetically-operated means for indicating the condition of the last means.
3. In combination, an elevator-shaft, acage, a door for regulating the passage of passengers to and from the cage, means for automatically preventing movement of the cage when the door is open, and magnetically-operated means carried by the cage for indicating the condition of the last means.
4. In combination, an elevator-shaft, landing-doors therefor, a cage in the shaft, means for automatically preventing movement of the cage after it has been brought to a stop and a door is open, and magnetically-operated means for indicating the condition of the last means.
5. In combination, an elevator-shaft, a cage,
IOO
a door for regulating the passage of passengers to and from the cage, a controller for the cage, means for locking the controller and allowing a limited movement thereof for cushioning when said door is open, and magnetically-operated means. for indicating a locked or unlocked condition of the controller.
6. In combination, an elevator-shaft, landing-doors therefor, a cage in the shaft, a controller for the cage, and vmeans for automatically locking the controller when a landingdoor is open, and means for unlocking the controller when the door is shut, and magnetically-operated means for indicating a locked or unlocked condition of the controller.
7. In combination, an elevator-shaft, landing-doors therefor, a cage in the shaft, a controller for the cage, magnetically-operated means for locking the controller, and for indicating a locked or unlocked condition of the controller, and means operated by said doors for controlling the magnetic means.
8. In combination, an elevator-shaft, landing-doors therefor, a cage in the shaft, a controller for the cage, a safety-indicator in the cage, and magnetically-operated means for locking the controller and for controlling said indicator.
9. In combination, an elevator-shaft, landing-doors therefor, a cage in the shaft, a controller for the cage, a safety-indicator Yin the cage, magnetically-operated means for locking the controller and for controlling said indicator, and means operated by said doors for controlling the magnetic means.
10. In combination, an elevator shaft, a cage in the shaft, a door for regulating the passage of passengers to and from the cage, a controller for the cage, a lock for the controller, a safety-indicator, a magnet for operating the lock and safety-indicator, an electric circuit through the magnet and safetyindicator, and means operated by the door for controlling the circuit.
11. In combination, an elevator-shaft, landing-doors therefor, a cage in the shaft, a controller for the cage, a lock for the controller, a safety-indicator in the cage, an electric circuit through the magnet and safety-indicator,- a magnet for operating the lock and safetyindicator, and means operated by the doors for controlling the circuit.
12. In combination, an elevator-shaft, a cage in the shaft, a door for regulating the passage of passengers to and from the cage, a controller for the cage, a lock for the controller allowing a limited movement of the same when locked, a magnet for operating the lock, a safety-indicator in the cage controlled by said magnet, an electric circuit through the magnet and safety-indicator and means operated by the door for controlling said circuit.
13. In combination, an elevator-shaft, a cage in the shaft, a door for regulating the passage of passengers to and from the cage, a shaft carried by the cage, a controlling-lever attached to the shaft, a sector carried by the shaft, a lock for the sector, means for adjusting the lock concentrically of the sector, and means operated by the door for controlling the lock.
14. In combination, a cage, a shaft carried by the cage, a controlling-lever attached to the shaft, a sector carried by the shaft, a lock for the sector, and means for adjusting the lock concentrically of the sector.
15. In combination, a cage, a shaft carried thereby, a controlling-lever attached to the shaft for rocking the same, a sector carried and rocked by the shaft and having a recess, a magnet-box hung concentrically With the sector, a locking-bolt slidably mounted in the box and adapted to enter the recess in the sector, a magnet in the boX, an armature therefor connected to the locking-bolt, and means for controlling the magnet.
16. In combination, a cage, a shaft carried thereby, a controlling-lever attached to the shaft, a magnet-box hung from the shaft, a sector att-ached to the -shaft and having a recess, a locking-bolt slidable in the magnetbox and adapted to enter the recess, a magnet in the box, an armature therefor connected with the locking-bolt, a circuit through the magnet, a lamp in the cage connected in parallel in the circuit, contact-clips forming terminals in the lamp-circuit, a contact-blade carried by the armature for closing the circuit through said clips, and means for controlling the iirst circuit.
17. In combination, a cage, a shaft carried thereby, a hub on the shaft having arms, a sector on the arms, a magnet-box having a split sleeve around said hub, and a locking mechanism carried by the magnet-box for engaging the sector.
In testimony whereof I have hereunto set my hand, at Los Angeles, California, this 2d day of February, 1905.
ROBERT H. GAYLORD.
In presence of- GEORGE T. HACKLEY, WARREN E. LLOYD.
US24518105A 1905-02-11 1905-02-11 Safety device for elevators. Expired - Lifetime US795112A (en)

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