US1369895A - Operating device for automatic gates - Google Patents

Operating device for automatic gates Download PDF

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US1369895A
US1369895A US342148A US34214819A US1369895A US 1369895 A US1369895 A US 1369895A US 342148 A US342148 A US 342148A US 34214819 A US34214819 A US 34214819A US 1369895 A US1369895 A US 1369895A
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gate
cylinder
rod
lift
vertical
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US342148A
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Thomas E Lightfoot
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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
    • B66B13/02Door or gate operation
    • B66B13/06Door or gate operation of sliding doors

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  • SHEETSSHEET 2- Giro (Mug 'UNITED STATES THOMAS E. LIGHTFOOT, OF LQTROBE, PENNSYLVANIA.
  • the invention relates to an operating device for automatic gates.
  • the object of the present invention is to provide a simple, practical and efiicient operating device for automatically raising or lowerin a gate or gates at any landing of mine hoist shafts or other elevator shafts when a cageor lift comes to rest at or leaves any predetermined landing point, whereby the possibility of 'any one falling down the shaft when the cage or lift is not at the landing will be effectually eliminated.
  • a further object of the invention is to provide an electrically controlled operating de. vice of this character equipped with means for cushioning both the opening and closing movements of a gate or gates so that the same will complete the opening and closing I movements without jar.
  • a further object of the invention is to provide a vertically slidable gate which when closed and locked against vertical movement may be unlocked and swung open for inspection and other purposes.
  • FIG. 1 is a side elevation of an automatic gate provided with an operating device constructed in accordance with this invention
  • Fig. 2 is an end elevation of the gate operating mechanism
  • Fig. 3 is an elevation of the automatic latch and trip device
  • Fig. 4 is a plan view of the same.
  • 1 designates a vertically slidable gate guided by spaced vertical side rods 2 and 3 located at the sides of the gate and receiving vertically alined eyes 4:, 5, and 6, the, eyes 5 and 6 being provided with removable sections to enable them to be disconnected from the vertical rod 8 for permitting the gate to swing horizontally on the vertical rod 2 which is adapted to operate as proper authorities so that under normal conditions the gate will be adapted to have only a vertical slidable movement.
  • the lower eye or slide member 6 is' provided with a depending substantially L- shaped keeper 7 having an inwardly extending lug or arm 8 at the-lowerend adapted to be engaged by a slidable spring actuated rod 9 mounted insuitable guides 10 and 11 and normally urged to its closed position 'by a spring 12 disposed on the rod and interposed between the 'guide 11 and the key 13 of the'locking rod 9.
  • the spring is adapted to project one end of the locking rod from the arm 8 for preventing upward movement of the gate, and the other .end of-the locking rod is pivotally connected at 14: to one end of a short lever 15 fulcrumed at an intermediate point at 16 in a suitable bracket or support 17 and provided at the other end 18 with an anti-friction roller 19 arranged to run on atripping device 20 carried by one of the frame members 21 of the cage or lift.
  • the tripping device consists of a vertical plate or bar having upper and lower inclined end portions 22 an terminal attaching portions 23 which are suitabl secured to the frame member 21. on t e lift or cage approaches the landing one ofthe inclined portions 22 engages an antifriction roller 19 of the lever 15 and swings the lever to the gate has an opportunity to close and the keeper reach the position to be engaged by the locking rod.
  • the gate is provided with a central hanger 24 which is secured to one end of a steel rope 25 or other suitable flexible connection which extends upwardly to an overhead guide pulley 26 and over said guide pulley 26 to a guide pulley 27 preferably located within the engine housed as diagrammatically illustrated in Fig. 1 of the drawings.
  • the cable extends downwardly from the guide pulley 27 beneath a pulley 28 and then upward at the opposite side of the same to a suitable fastening device 29 forming a loop to receive the said pulley 28.
  • the fastening device 29 may consist of an ey-ebolt, or any other suitable device secured to the ceiling of the engine room or other suitable support.
  • the pulley 28 is moved downwardly by compressed air or other fluid pressure operating in a cylinder 30 having a piston consisting of a head 31 and a rod 32 connected with the pulley whereby when fluid pressure is admitted into the upper end of the cylinder by the means hereinafter described, the piston will be forced downwardly and will carry with it the pulley 28 and thereby elevate the gate 1.
  • This is effected by the said controlling means and the operation occurs as the cage approaches the landing. -When the cage reaches the landing the fluid pressure is cut off from the'upper end of the cylinder and the latter is connected with the atmosphere to permit the fluid pressure to exhaust and the gate moves downward by gravity to its closed position.
  • Compressed air, steam, or other fluid pressure may be employed in the operation of the piston and the cylinder is preferably mounted upon a concrete base 33 and has secured to it at opposite sides vertical guide rods 34 attached to the cylinder byupper and lower bands 36.
  • the upper and lower bands 36 are provided with enlargements 37 through which the guide rods 34 pass and the lower ends of the guide rods are preferably threaded for-the reception of nuts 38, but any other suitable means may be employed for mountingthe guide rods upon the cylinder.
  • the guide rods extend upwardly above the cylinder and receive a vertically slidable frame 39 to which the upper end of the piston rod 32 is secured and in which is mounted the pulley 28.
  • the guide rods extend through the slidable frame and upper cushioning or shock absorbing springs 40 are arranged upon the guide rods and are compressed'by the slidable frame 39 in the upward movement thereof as the gate completes its closing movement.
  • the cylinder has mounted upon it shock absorbing spring a1 located between the piston rod and the guide rods and arranged 1 to be compressed by the slidable frame 39, as the gate completes its opening movement. These springs also assist the starting of the gate after the closing movement thereof when the controlling means is operated to exhaust the pressure within. the cylinder. By this construction, both the opening and closing movements of the gate are cushioned and the gate is opened and closed without'jar orshock.
  • the cylinder is connected with an air line pipe 4.2 or other iiuid pressure pipeand the admission of fluid pressure to the cylinder and the exhaust of fluid pressure therefrom is controlled by electrically operated pneumatic valves 43 connected at one end with an air line pipe 42 and at the other end with the cylinder by a pipe 44 and arranged in an electric circuit including a battery 45 or other source of electric current supply and an automatic switch.
  • the automatic switch is preferably in the form of an indicator dial 46 having an indicator hand 47 mounted on a shaft 48 having a belt and pulley connection 49 with the drum 50 which raises and lowers the cage or lift. The drum and the belt and pulley connection are indicated.
  • Fig. 1 diagrammatically in Fig. 1 and the dial is equipped with spaced contacts 51 adapted to be engaged by the indicator hand for closing the electric circuit 52 when the cage is at the top landing or at any other predetermined landing point.
  • the electric circuit 52 When the electric circuit 52 is closed the electrically operated pneumatic valves are actuated to close the upper end ofthe cylinder to the atmosphere and connect the upper end of the cylinderwith the air line pipe to admit compressed air into the cylinder for actuating the piston to open the gate.
  • one or more cushioning springs may be disposed around the piston rod,- as
  • a device of the class described. including a vertical sliding gate, guiding mechanism provided with means for permitting the gate to swing horizontally, and means for locking the gate against vertical movement without interfering with the horizontal swinging movement.
  • a device of the class described including a vertical sliding. gate, 1 guiding mech anism provided with means for permitting the gate to swing horizontally, and an automatic cage operated latch arranged to lock the gate against vertical movement without interfering with the horizontal swinging movement of the gate.
  • a device of the class described including avertical sliding gate, guiding mechanism provided with means for permitting the gate to swing horizontally, and means for locking the gate against vertical movement without interfering with the horizontal swinging movement, comprising a keeper carried by the gate, a horizontally slidable locking rod arranged to engage the keeper, means for automatically urging the rod to its engaging position, and means arranged to be actuated by a cage 'or lift for withdrawing the rod from engagement with the keeper.
  • a device of the class described including a vertical sliding gate, guiding mechanism provided with means for permitting the gate to swing horizontally, a keeper carried by the gate, a slidable locking rod,
  • a spring for urging the rod into engagement with the keeper
  • a lever connected with the rod for moving the same against the action of the spring
  • a trip designed to be mounted on a cage or lift for actuating the lever
  • a device of the class described including a vertical sliding gate, guiding mechanism provided with means for permitting the gate to swing horizontally, a keeper carried by the gate, a slidable locking rod, a spring for urging the rod into engagement with the keeper, a lever pivoted at .an intermediate point and connected at one end with a rod provided at the other end. with an anti-friction device, the trip design being mounted on a cage or lift for engaging the anti-friction device to withdraw the rod from its engaging features.
  • a device of the class described including a vertically movable gate, a keeper carried by the gate, a slidable locking rod arranged to engage the keeper, a spring for urging the rod into such engagement, a lever connected with the rod for moving the same out of such engagement, and a tripping device designed to be mounted on a cage or lift and having inclined end portions for actuating the lever and a vertlcal connecting portionfor holding thelever to maintaln the sliding rod out of engagement with the keeper,
  • Afdevice of the class described including 'a vertically slidable gate, a rope or carried to and from the said contacts to' open .and close the circuit.
  • a device of the'class described including a vertically movable gate, a rope or cable connected with the gate and arranged.
  • a cylinder having a piston, aframe carried by the p'istonand having a pulley operating in the loop, means for guiding the frame, and shock absorbing springs located at the top and bottom of the guiding means and arranged in the path of the frame for cushioning the opening and closing movements of the gate.
  • a device of the character described including a vertical movable gate, a rope or cable connected with the gate, and means for operating the rope or cable for raising and lowering the gate, said means comprising a cylinder having a piston provided with a piston rod, a cross head or frame connected with the piston rod, guide rods receiving and guiding the cross head, and springs mounted onthe guide rods andon the piston rod and arranged to cushion the cross head at the upper and lower limits of the movements thereof.
  • a device of the class described including a vertically movable gate, a rope or cable connected with the gate and arranged to lift the same and provided with a loop, a vertical cylinder having a piston, vertical guide rods mounted on the cylinder at opposite sides thereof, 1 a frame slidable along the guide rods and actuated by the piston in its downward movement, a pulley'mounted in the frame and operated in the loop of the rope or cable to lift the gate, and means for admitting fluid pressure to and exhausting fluid pressure from the cylinder.

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Description

T. E. LIGHTFOOL OPERATING DEVICE FOR AUTOMATIC GATES.
APPLICATION FILED DEC-3,1919.
Patented Mar. 1; 1921.
2 SHEETS-SHEET 1- T. E. LIGHTFOOT.
OPERATING DEVICE FOR AUTOMATIC GATES.
APPLICATION FILED DEC.3, 1919.
Patented Mar. 1, 1921.
2 SHEETSSHEET 2- Giro (Mug 'UNITED STATES THOMAS E. LIGHTFOOT, OF LQTROBE, PENNSYLVANIA.
OPERATING nnvron non AUTOMATIC earns,
Specification of Letters Patent. I
Patented Mar. 1, 1921.
Application filed December 3, 1919. Serial'No. 342,148.
To all whom it mag concern Be it known that I, THOMAS E. LIcHTroo'r, a citizen of the United States, residing at Latrobe, in the county of Westmoreland and State of Pennsylvania, have invented new and useful Improvements in Operating Devices for Automatic Gates, of which the following is a specification.
The invention relates to an operating device for automatic gates.
The object of the present invention is to provide a simple, practical and efiicient operating device for automatically raising or lowerin a gate or gates at any landing of mine hoist shafts or other elevator shafts when a cageor lift comes to rest at or leaves any predetermined landing point, whereby the possibility of 'any one falling down the shaft when the cage or lift is not at the landing will be effectually eliminated.-
A further object of the invention is to provide an electrically controlled operating de. vice of this character equipped with means for cushioning both the opening and closing movements of a gate or gates so that the same will complete the opening and closing I movements without jar.
It is also an object of the invention to provide an automatically operated locking device adapted to securely fasten the gate in its closed position. I
A further object of the invention is to provide a vertically slidable gate which when closed and locked against vertical movement may be unlocked and swung open for inspection and other purposes.
With these and other objects in view, the invention consists in the construction and novel combination and arrangement of parts hereinafter fully described, illustrated in the accompanying drawings and pointed out in the claims hereto appended, it being understood that various changes in the form, proportion, size and minor details of construction, within the scope of the claims, may be resorted towithout departing from the spirit of the invention or sacrificing any of the advantages thereof.
In the drawings, in which like characters of reference designate corresponding parts in the several figures:
Figure 1 is a side elevation of an automatic gate provided with an operating device constructed in accordance with this invention;
Fig. 2 is an end elevation of the gate operating mechanism;
Fig. 3 is an elevation of the automatic latch and trip device; and
Fig. 4 is a plan view of the same.
In the accompanying drawings, in which is illustrated the preferred embodiment of the invention, 1 designates a vertically slidable gate guided by spaced vertical side rods 2 and 3 located at the sides of the gate and receiving vertically alined eyes 4:, 5, and 6, the, eyes 5 and 6 being provided with removable sections to enable them to be disconnected from the vertical rod 8 for permitting the gate to swing horizontally on the vertical rod 2 which is adapted to operate as proper authorities so that under normal conditions the gate will be adapted to have only a vertical slidable movement.
The lower eye or slide member 6 is' provided with a depending substantially L- shaped keeper 7 having an inwardly extending lug or arm 8 at the-lowerend adapted to be engaged by a slidable spring actuated rod 9 mounted insuitable guides 10 and 11 and normally urged to its closed position 'by a spring 12 disposed on the rod and interposed between the 'guide 11 and the key 13 of the'locking rod 9. The springis adapted to project one end of the locking rod from the arm 8 for preventing upward movement of the gate, and the other .end of-the locking rod is pivotally connected at 14: to one end of a short lever 15 fulcrumed at an intermediate point at 16 in a suitable bracket or support 17 and provided at the other end 18 with an anti-friction roller 19 arranged to run on atripping device 20 carried by one of the frame members 21 of the cage or lift. The tripping device consists of a vertical plate or bar having upper and lower inclined end portions 22 an terminal attaching portions 23 which are suitabl secured to the frame member 21. on t e lift or cage approaches the landing one ofthe inclined portions 22 engages an antifriction roller 19 of the lever 15 and swings the lever to the gate has an opportunity to close and the keeper reach the position to be engaged by the locking rod.
The gate is provided with a central hanger 24 which is secured to one end of a steel rope 25 or other suitable flexible connection which extends upwardly to an overhead guide pulley 26 and over said guide pulley 26 to a guide pulley 27 preferably located within the engine housed as diagrammatically illustrated in Fig. 1 of the drawings. The cable extends downwardly from the guide pulley 27 beneath a pulley 28 and then upward at the opposite side of the same to a suitable fastening device 29 forming a loop to receive the said pulley 28. The fastening device 29 may consist of an ey-ebolt, or any other suitable device secured to the ceiling of the engine room or other suitable support. The pulley 28 is moved downwardly by compressed air or other fluid pressure operating in a cylinder 30 having a piston consisting of a head 31 and a rod 32 connected with the pulley whereby when fluid pressure is admitted into the upper end of the cylinder by the means hereinafter described, the piston will be forced downwardly and will carry with it the pulley 28 and thereby elevate the gate 1. This is effected by the said controlling means and the operation occurs as the cage approaches the landing. -When the cage reaches the landing the fluid pressure is cut off from the'upper end of the cylinder and the latter is connected with the atmosphere to permit the fluid pressure to exhaust and the gate moves downward by gravity to its closed position.
Compressed air, steam, or other fluid pressure, may be employed in the operation of the piston and the cylinder is preferably mounted upon a concrete base 33 and has secured to it at opposite sides vertical guide rods 34 attached to the cylinder byupper and lower bands 36. The upper and lower bands 36 are provided with enlargements 37 through which the guide rods 34 pass and the lower ends of the guide rods are preferably threaded for-the reception of nuts 38, but any other suitable means may be employed for mountingthe guide rods upon the cylinder. The guide rods extend upwardly above the cylinder and receive a vertically slidable frame 39 to which the upper end of the piston rod 32 is secured and in which is mounted the pulley 28. The guide rods extend through the slidable frame and upper cushioning or shock absorbing springs 40 are arranged upon the guide rods and are compressed'by the slidable frame 39 in the upward movement thereof as the gate completes its closing movement. The cylinder has mounted upon it shock absorbing spring a1 located between the piston rod and the guide rods and arranged 1 to be compressed by the slidable frame 39, as the gate completes its opening movement. These springs also assist the starting of the gate after the closing movement thereof when the controlling means is operated to exhaust the pressure within. the cylinder. By this construction, both the opening and closing movements of the gate are cushioned and the gate is opened and closed without'jar orshock.
The cylinder is connected with an air line pipe 4.2 or other iiuid pressure pipeand the admission of fluid pressure to the cylinder and the exhaust of fluid pressure therefrom is controlled by electrically operated pneumatic valves 43 connected at one end with an air line pipe 42 and at the other end with the cylinder by a pipe 44 and arranged in an electric circuit including a battery 45 or other source of electric current supply and an automatic switch. The automatic switch is preferably in the form of an indicator dial 46 having an indicator hand 47 mounted on a shaft 48 having a belt and pulley connection 49 with the drum 50 which raises and lowers the cage or lift. The drum and the belt and pulley connection are indicated.
diagrammatically in Fig. 1 and the dial is equipped with spaced contacts 51 adapted to be engaged by the indicator hand for closing the electric circuit 52 when the cage is at the top landing or at any other predetermined landing point. When the electric circuit 52 is closed the electrically operated pneumatic valves are actuated to close the upper end ofthe cylinder to the atmosphere and connect the upper end of the cylinderwith the air line pipe to admit compressed air into the cylinder for actuating the piston to open the gate. As soon as the cage or lift leaves the landing the indicator hand will move awayzfromthe spaced contacts and the circuit will be broken to cause the electrically operated pneumatic valves to reverse their positions and cut off the compressed air supply and connect the upper end of the cylinder with the atmosphere to "permit the pressure within the cylinder to ex haust and cause the gate to close by gravity.
Instead of mounting the lower cushioning springs upon the cylinder at opposite sides of the piston rod between the same and the guide, rods one or more cushioning springs may be disposed around the piston rod,- as
- shown, forcushioning the opening move- .ment of the gate. e
What is claimed is 1 v v l. A device of the class described. including a vertical sliding gate, guiding mechanism provided with means for permitting the gate to swing horizontally, and means for locking the gate against vertical movement without interfering with the horizontal swinging movement.
2. A device of the class described including a vertical sliding. gate, 1 guiding mech anism provided with means for permitting the gate to swing horizontally, and an automatic cage operated latch arranged to lock the gate against vertical movement without interfering with the horizontal swinging movement of the gate.
3. A device of the class described including avertical sliding gate, guiding mechanism provided with means for permitting the gate to swing horizontally, and means for locking the gate against vertical movement without interfering with the horizontal swinging movement, comprising a keeper carried by the gate, a horizontally slidable locking rod arranged to engage the keeper, means for automatically urging the rod to its engaging position, and means arranged to be actuated by a cage 'or lift for withdrawing the rod from engagement with the keeper.
4. A device of the class described including a vertical sliding gate, guiding mechanism provided with means for permitting the gate to swing horizontally, a keeper carried by the gate, a slidable locking rod,
a spring for urging the rod into engagement with the keeper, a lever connected with the rod for moving the same against the action of the spring, and a trip designed to be mounted on a cage or lift for actuating the lever.
5. A device of the class described including a vertical sliding gate, guiding mechanism provided with means for permitting the gate to swing horizontally, a keeper carried by the gate, a slidable locking rod, a spring for urging the rod into engagement with the keeper, a lever pivoted at .an intermediate point and connected at one end with a rod provided at the other end. with an anti-friction device, the trip design being mounted on a cage or lift for engaging the anti-friction device to withdraw the rod from its engaging features. a
6. A device of the class described including a vertically movable gate, a keeper carried by the gate, a slidable locking rod arranged to engage the keeper, a spring for urging the rod into such engagement, a lever connected with the rod for moving the same out of such engagement, and a tripping device designed to be mounted on a cage or lift and having inclined end portions for actuating the lever and a vertlcal connecting portionfor holding thelever to maintaln the sliding rod out of engagement with the keeper, A H 27. Afdevice of the class described including 'a vertically slidable gate, a rope or carried to and from the said contacts to' open .and close the circuit.
8. A device of the'class described including a vertically movable gate, a rope or cable connected with the gate and arranged.
to lift the same and provided with a loop,
a cylinder having a piston, aframe carried by the p'istonand having a pulley operating in the loop, means for guiding the frame, and shock absorbing springs located at the top and bottom of the guiding means and arranged in the path of the frame for cushioning the opening and closing movements of the gate. a
9. A device of the character described including a vertical movable gate, a rope or cable connected with the gate, and means for operating the rope or cable for raising and lowering the gate, said means comprising a cylinder having a piston provided with a piston rod, a cross head or frame connected with the piston rod, guide rods receiving and guiding the cross head, and springs mounted onthe guide rods andon the piston rod and arranged to cushion the cross head at the upper and lower limits of the movements thereof.
10. A device of the class described including a vertically movable gate, a rope or cable connected with the gate and arranged to lift the same and provided with a loop, a vertical cylinder having a piston, vertical guide rods mounted on the cylinder at opposite sides thereof, 1 a frame slidable along the guide rods and actuated by the piston in its downward movement, a pulley'mounted in the frame and operated in the loop of the rope or cable to lift the gate, and means for admitting fluid pressure to and exhausting fluid pressure from the cylinder.
11. A device of the class described in .cluding a vertically movable gate, a rope or cable connected with the gate and arranged to lift the same and provided with a loop, a vertical cylinder having a piston,
vertical'guide rods mounted on the cylinfder at opposite sides thereof, a frame slidable along the 'guide'rods and actuated by the piston in its downward movement; a
ed on the guide rods at the upper end thereof and a'rrangedto be compressed by the frame, and lower'shock absorbing springs mounted on the cylinder and arranged to 10 be compressed by the frame in-the doWn- Ward movement there0f.- V
In testimony whereof I have hereunto set my hand. 7
THOMAS E; Ie T ooT,
US342148A 1919-12-03 1919-12-03 Operating device for automatic gates Expired - Lifetime US1369895A (en)

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