US399716A - Electrically-controlled hydraulic elevator - Google Patents

Electrically-controlled hydraulic elevator Download PDF

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US399716A
US399716A US399716DA US399716A US 399716 A US399716 A US 399716A US 399716D A US399716D A US 399716DA US 399716 A US399716 A US 399716A
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pressure
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lever
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66BELEVATORS; ESCALATORS OR MOVING WALKWAYS
    • B66B1/00Control systems of elevators in general
    • B66B1/02Control systems without regulation, i.e. without retroactive action
    • B66B1/04Control systems without regulation, i.e. without retroactive action hydraulic

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  • the pump employed to feed the water from the receiving or storage reservoir into the pressure tank or reservoir in which the water is maintained under proper pressure to actuate the hoisting mechanism is placed under the control of an electrically-actuated motor located in the building, but set in motion by a dynamo or other source of electricity situated, it may be, at a distant point or power-station.
  • the pressure upon the water in the pressure tank or reservoir controls, through a suitable regulator, the electric circuit in which the motor is placed, the regulator acting automatically, so that the said motor and pump may be actuated or be left at rest, according to the amount of pressure in the tank or reservoir and the requirements of the elevator.
  • My invention therefore consists, essentially, in a hydraulic-elevator system, of a regulator operated by changes in pressure of the fluid used to actuate the elevator, a pump, and an electric motor, combined with a switch controlled by the regulator to aifect the circuit of the electric motor to start or stop the pump, according the pressure of the liuid employed, substantially as will be described.
  • FIG. 1 in section and elevation represents a building provided with an elevator operated after the Hinkle system, the drawings showing a sufficient portion of my improved system by which the l-Iinkle system is controlled to enable my invention to be understood.
  • Fig. 2 is a diagram showing one manner of connecting the electric motor with the switch controlling the operation of the motor, and also the cylinder and piston operating the switch, shown as a lever, the pipe connecting the said cylinder with the pressure-tank being broken off;
  • Fig. 3 a diagram showing the cylinder, its piston, the switch-lever connected with the said piston, the pressure-tank connected to the cylinder by a straight pipe provided with a relief-valve, and a branch pipe connected to the discharge tank and switch an electric motor difierently constructed from that shown in Fig. 2; and Fig. 5, a
  • the elevator-carA is herein shown as operated in accordance with the Hinkle system, the car being suspended in a hoistway formed between walls a of a building or other structure by a rope, a, passed about a sheave, a at or near the top of the building and about a movable sheave, a and a fixed or stationary sheave, C0 in the basement of the building, the movable sheave being connected to and operated by the piston-rod of a piston reciprocating in a cylinder, a herein shown as upright, the said piston being operated by water or other fluid contained under pressure in the tank or reservoir B, substantially such as shown and described in United States Patent No.
  • the said fluid being supplied to the pressure tank or reservoir B from the receiving or storage tank B by a pump, E the fluid used to raise the elevator-car being discharged into the said tank B on the descent of the car.
  • the pump B is actuated by steam from a boiler. (Not herein shown, but which in practice is located in the basement of the building.)
  • the power to operate the pump is an electrically-actuated motor, D, the armature-shaft b of which is herein shown as provided with a small pulley, 6, connected by a belt, b to a large pulley, b mounted upon a shaft, 17*, supported in suitable bearings, secured, as shown in Fig. 1, to the basement-ceiling.
  • the shaft b also has mounted upon it a small pulley, 6 connected by abelt, b, to a pulley, If, on the main or crank shaft 19 of the pump B rotation of the armature-shaft b revolving the crankshaft 1) through the pulleys and belting described.
  • the motor D is actuated by electricity derived from a dynamo or other suitable source of supply, (not herein shown,) and which in practice may be at a distant point or station, the circuit in which the motor is placed being automatically controlled through a regulator, as will be described, by the pressure in the tank or reservoir B.
  • the compound-wound motor (shown in Fig.
  • a switch herein shown as alever, d, pivotally connected to the rod cl of a piston, (1 the latter reciprocating in a cylinder, d connected by the pipe d to the pressure-tank B, the said piston being shown as extended through its cylinder (Z and provided at its end with weights to bring the piston to the bottom of the said cylinder, when the pressure of fluid in the pressure-tank is reduced below the required or established pressure, as will be described, the lever (1 having connected to it the positive line-wire (V.
  • the cylinder (1 and its piston constitute what I shall herein designate the regulator.
  • the pipe d has a branch pipe, 6, (see Figs. 1 and 3,) which leads, as shown, to the receiving or storage tank B, and is provided with a cock, 6, the said branch pipe forming the outlet or discharge pipe for the cylinder (1 Between the pressure-tank B and the branch pipe 6 the pipe (Z is provided with a reliefvalve, e which may be one such as shown and described in United States Patent No.
  • the cock 6 in the branch pipe 6 may be turned or adjusted so as to provide a smaller or larger outlet-passage, as desired, leading to the cylinder (1 thereby controlling the rate of downward movement of the piston (1 and consequently of the lever (I, under the action of the weights.
  • the pipe (1" is likewise provided with a cock, a located between the relief-valve and the pressure-tank, and employed to prevent a too sudden opening of the said relief-valve.
  • the primary coil 10 of higher resistance than the auxiliary coil 5, and shown by dotted lines, is in a shunt-circuit around the brushes 12 13, the brush 12 being connected by wire 14: with the button 15 and the brush 13 with the negative line-wire 16.
  • the relief-valve e is first adjusted so as to open when the pressure in the tank B equals or exceeds that at which it is desired to run the elevator, which point, for sake of illustration, may be seventy pounds.
  • the pressure in the tank which point, for sake of illustration, may be seventy pounds.
  • the relief-valve is open and the fluid admitted to the cylinder (1 has moved the piston (1 and thereby the lever (I, into the posit-ions shown in Fig. 2, and the lever (I being out of contact with the stud 6 the circuit of the motor is broken at this point and the motor is stopped.
  • the pressure in the tank B is reduced below the normal. hen the pressure in the tank B falls below the normal, the valve e closes and the weight (Z or it may be a spring, acts to draw the piston down in the cylinder (7 thereby bringing the switch-lever into contact with the studs or buttons to which the resistances are joined. ⁇ Vhen the lever (1 comes in contact with the stud 6, the circuit of the motor is completed through the resistances, and the auxiliary primary coil 5, thus rotating the armature and actuating the pump to force more fluid into the pressure-tank.
  • the weight Z or it may be a spring
  • the resistances should be gradually eliminated, in order that the current of full strength may not flow through the armature before the latter has attained a considerable velocity, and thereby generated in itself a counter-electro-motive force to oppose and weaken the actuating current.
  • the cock 6' in the branch pipe 6 is so adjusted as to afford a small outlet for the water in the cylinder (7 causing the piston d to descend slowly, and thereby moving the lever (l gradually over the studs or buttons.
  • the resistances are cut out of circuit when the lever (Z is brought in contact with the stud 15, the velocity of rotation of the armature being then at its maximum and the circuit of the motor being completed through the line ll, the motor bein then a simple shunt-machine, a part of the current flowing through the primary field-coil 10.
  • the motor continues to actuate the pump until the pressure in the tank B equals or exceeds the normal, and when this point is reached the valve e opens to operate the lever d, as above described, to break the circuit of the motor, substantially in an instant, and stop the rotation of its armature.
  • the motor shown is a series motor, in which the negative line-wire is connected to one brush and the positive line-wire dto the lever d.
  • the circuit of the motor is completed when the lever d co-operates with the contact-terminal f, to which one end of the field-wire 17 is connected.
  • the fieldcoil forms a part of the main circuit, and the resistance of the said coil is suflicient to prevent injurious action when the motor is started.
  • I claim 1 In a hydraulic-elevator system, a regulater operated by changes in pressure of the fluid used to actuate the elevator, a pump, and an electric motor, combined with a switch controlled by the regulator to affect the circuit of the electric motor to start or stop the pump according to the pressure of the fluid employed, substantially as described.
  • a closed tank to contain a fluid under press- IIO ure
  • a pump to force the fluid into the said tank
  • an electrically-actuated motor to operate the said pump at intervals, combined with a regulator under the control of the fluid under pressure in the tank, and with a switch to control the circuit of the electric motor, the said instrumentalities operating substantially as described.
  • a closed tank to contain a fluid under pressure
  • a pump to force the fluid into the said tank
  • an electrically-actuated motor to operate the said pump at intervals, combined with a regulator under the control of the fluid under pressure in the tank, an d with a resistance and a lever co-operating therewith and controlled by the said regulator to affect the circuit of the electric motor, as and for the purpose specified.
  • a tank to contain a fluid under pressure, a pump, and an electric motor, a resistance and a lever co-operating therewith, and a piston connected to the said lever and actuated by fluid from the pressure-tank to move the said lever, combined with a relief-valve to control the fluid actuating the said piston, and with means, substantially as described, to move the piston in a direction opposite to that in which it is moved by the actuating-fluid, as and for the purpose specified.
  • a tank to contain a fluid under pressure, a pump, and an electric motor, a resistance and a lever co-operating therewith, a regulator in operative connection with the said lever, a pipe connecting said regulator with the pressure-tank, and a branch pipe forming a discharge-pipe for the said regulator, combined with a relief-valve to control the admission of fluid to the said regulator, and with a valve in the branch pipe to control the passage of fluid from the said regulator, as and for the purpose specified.

Description

2 Sheets-Sheet 1.
(No Model.)
0. WHITTIER.
ELEOTRIOALLY GONTROLLBD HYDRAULIC ELEVATOR.
N0. 399,7 Patented Mar. 19, 1889.
wan 63565 ju X? N. PETERS. Phomuxhu m hev. Washington. D. c.
2 Sheets-Sheet 2.
(No Model.)
0. WHITTIER.
ELEGTRIGALLY CONTROLLED HYDRAULIC ELEVATOR. No. 399,716,
Patented Mar. 19, 1889.
N. Finns, Pnummm n' her, Wishingtan. D. c.
UNITED STATES PATENT OFFICE.
CHARLES \VHITTIER, OF BOSTON, MASSACHUSETTS.
ELECTRlCALLY-CONTROLLED HYDRAULIC ELEVATOR.
SPECIFICATION forming part of Letters Patent No. 399,716, dated March 19, 1889.
Application filed January 25, 1887. Serial No. 225,433. (No model.)
To all whom it may concern.-
Be it known that 1, CHARLES WHITTIER, of Boston, county of Suffolk, and State of Massachusetts, have invented an Improvement in Hydraulic-Elevator Systems, of which such as a pump and an engine to actuate it have to be provided to return the water from the discharge or storage reservoir to the pressure-tank, as in the Hinkle system, or to the cylinder of the hoisting mechanism, and an engineer has to be employed to run the engine.
The chief expense of running a hydraulic elevator, aside from the attendant on the car,
usually a boy, is for the engineer to run the engine and the cost of coal or other fuel used to supply the motive power.
The employment in the basement of a building of an engine by which to operate an elevator is very objectionable in the summer on account of the heat produced, and to many people the presence in the basement of an engine requiring a constant fire and producing considerable noise is sufficient to deter the introduction of an elevator where otherwise it would be employed.
In my experiments to overcome the foregoing objections and render unnecessary the employment of a steam-boiler, engine, and engineer in a building wherein a hydraulic elevator is to be used, so that the said elevator may be run at the minimum expense and without heating the basement and buildin I have devised a system, to be described, which is herein shown as especially adapted to be used in connection with the Hinkle system referred to, but which may be used with any other system wherein the fluid which operates the elevator is stored under pressure or kept in a high column.
In embodying my invention, as herein shown, with the Hinkle system the pump employed to feed the water from the receiving or storage reservoir into the pressure tank or reservoir in which the water is maintained under proper pressure to actuate the hoisting mechanism is placed under the control of an electrically-actuated motor located in the building, but set in motion by a dynamo or other source of electricity situated, it may be, at a distant point or power-station. The pressure upon the water in the pressure tank or reservoir controls, through a suitable regulator, the electric circuit in which the motor is placed, the regulator acting automatically, so that the said motor and pump may be actuated or be left at rest, according to the amount of pressure in the tank or reservoir and the requirements of the elevator.
My invention therefore consists, essentially, in a hydraulic-elevator system, of a regulator operated by changes in pressure of the fluid used to actuate the elevator, a pump, and an electric motor, combined with a switch controlled by the regulator to aifect the circuit of the electric motor to start or stop the pump, according the pressure of the liuid employed, substantially as will be described.
Other features of my invention will be pointed out in the claims at the end of this specification.
Figure 1 in section and elevation represents a building provided with an elevator operated after the Hinkle system, the drawings showing a sufficient portion of my improved system by which the l-Iinkle system is controlled to enable my invention to be understood. Fig. 2 is a diagram showing one manner of connecting the electric motor with the switch controlling the operation of the motor, and also the cylinder and piston operating the switch, shown as a lever, the pipe connecting the said cylinder with the pressure-tank being broken off; Fig. 3, a diagram showing the cylinder, its piston, the switch-lever connected with the said piston, the pressure-tank connected to the cylinder by a straight pipe provided with a relief-valve, and a branch pipe connected to the discharge tank and switch an electric motor difierently constructed from that shown in Fig. 2; and Fig. 5, a
' modification, to be referred to.
The elevator-carA is herein shown as operated in accordance with the Hinkle system, the car being suspended in a hoistway formed between walls a of a building or other structure by a rope, a, passed about a sheave, a at or near the top of the building and about a movable sheave, a and a fixed or stationary sheave, C0 in the basement of the building, the movable sheave being connected to and operated by the piston-rod of a piston reciprocating in a cylinder, a herein shown as upright, the said piston being operated by water or other fluid contained under pressure in the tank or reservoir B, substantially such as shown and described in United States Patent No. 183,055, dated October, 1876, the said fluid being supplied to the pressure tank or reservoir B from the receiving or storage tank B by a pump, E the fluid used to raise the elevator-car being discharged into the said tank B on the descent of the car. In this system as now commonly employed the pump B is actuated by steam from a boiler. (Not herein shown, but which in practice is located in the basement of the building.)
In accordance with my present invention I obviate the employment of a steam-boiler, which is especially objectionable in summer on account of the heatproduced, and also the employment of an engineer, both of which, the one to make and the other to control the steam, constitute the chief cost of running an elevator.
In accordance with my invention the power to operate the pump is an electrically-actuated motor, D, the armature-shaft b of which is herein shown as provided with a small pulley, 6, connected by a belt, b to a large pulley, b mounted upon a shaft, 17*, supported in suitable bearings, secured, as shown in Fig. 1, to the basement-ceiling. The shaft b also has mounted upon it a small pulley, 6 connected by abelt, b, to a pulley, If, on the main or crank shaft 19 of the pump B rotation of the armature-shaft b revolving the crankshaft 1) through the pulleys and belting described.
The motor D is actuated by electricity derived from a dynamo or other suitable source of supply, (not herein shown,) and which in practice may be at a distant point or station, the circuit in which the motor is placed being automatically controlled through a regulator, as will be described, by the pressure in the tank or reservoir B.
To enable the action of my improved system to be clearly understood, I have shown the manner of connecting the motor D in circuit, which motor, as preferred by me, and as shown in Fig. 2, is the well-known compoundwound Daft electric motor.
The compound-wound motor (shown in Fig.
2) is placed in operative connection with the line or current-supplying circuit by a switch, herein shown as alever, d, pivotally connected to the rod cl of a piston, (1 the latter reciprocating in a cylinder, d connected by the pipe d to the pressure-tank B, the said piston being shown as extended through its cylinder (Z and provided at its end with weights to bring the piston to the bottom of the said cylinder, when the pressure of fluid in the pressure-tank is reduced below the required or established pressure, as will be described, the lever (1 having connected to it the positive line-wire (V. The cylinder (1 and its piston constitute what I shall herein designate the regulator.
When the electromotor employed is a compound-wound machine, as shown in Fig. 2, it is necessary to prevent an excessive amount of current from passing through the armature before the latter has attained a considerable velocity, for if, in the case of a compoundwound machine, the armature-circuit should be immediately closed before the said armature had attained a considerable velocity, an excessive current would pass therethrough and cause sparking at the brushes, which would be so great as to destroy them.
It is well known that when an electromotor is running at considerable velocity there is a reaction current set up in an opposite direction to that which produces the motion, such reaction currentt ending to produce a counterelectro-motive force.
WVhen the motor is first started, the counterelectro-motive force in the armature is m], and it is necessary, therefore, to employ resistances outside the machine which will reduce the current passing through the armature until the latter has attained a considerable velocity,,the resistance being gradually cut out as the velocity of the armature increases. To effect this result in the present instance, I have interposed in the circuit of the auxiliary primary coil 5 of the motor, as herein shown, three resistances, 2 3 4, connected to studs (5 '7 8 9, over which studs the lever d is moved. Instead of the resistance herein shown, I may employ any other wellknown form of resistance. The lever d is also pivoted at d to the usual box (shown in Fig. 1) containing the resistances; but it might be pivoted to any other suitable support. The pipe d has a branch pipe, 6, (see Figs. 1 and 3,) which leads, as shown, to the receiving or storage tank B, and is provided with a cock, 6, the said branch pipe forming the outlet or discharge pipe for the cylinder (1 Between the pressure-tank B and the branch pipe 6 the pipe (Z is provided with a reliefvalve, e which may be one such as shown and described in United States Patent No. 231,214, dated August, 1880, the said valve being opened to relieve the pressure in the tank B when the said pressure equals or exceeds a predetermined point, the water or other fluid from the tank thereafter flowing into the cylinder (1 below the piston (1 forcing the latter toward the other end of the said cylinder. The cock 6 in the branch pipe 6 may be turned or adjusted so as to provide a smaller or larger outlet-passage, as desired, leading to the cylinder (1 thereby controlling the rate of downward movement of the piston (1 and consequently of the lever (I, under the action of the weights. The pipe (1" is likewise provided with a cock, a located between the relief-valve and the pressure-tank, and employed to prevent a too sudden opening of the said relief-valve.
Referring to Fig. 2, it will be seen that the primary coil 10 of higher resistance than the auxiliary coil 5, and shown by dotted lines, is in a shunt-circuit around the brushes 12 13, the brush 12 being connected by wire 14: with the button 15 and the brush 13 with the negative line-wire 16.
In the operation of my improved system, and as thus far described, the relief-valve e is first adjusted so as to open when the pressure in the tank B equals or exceeds that at which it is desired to run the elevator, which point, for sake of illustration, may be seventy pounds. Let it be supposed that the car has been stopped at the first floor, as shown in Fig. 1, and that the pressure in the tank is normal. In this case the relief-valve is open and the fluid admitted to the cylinder (1 has moved the piston (1 and thereby the lever (I, into the posit-ions shown in Fig. 2, and the lever (I being out of contact with the stud 6 the circuit of the motor is broken at this point and the motor is stopped. If the attendant in the elevator operates the mechanism in the car so as to open the main valve, and thus cause the elevatorto ascend, the pressure in the tank B is reduced below the normal. hen the pressure in the tank B falls below the normal, the valve e closes and the weight (Z or it may be a spring, acts to draw the piston down in the cylinder (7 thereby bringing the switch-lever into contact with the studs or buttons to which the resistances are joined. \Vhen the lever (1 comes in contact with the stud 6, the circuit of the motor is completed through the resistances, and the auxiliary primary coil 5, thus rotating the armature and actuating the pump to force more fluid into the pressure-tank.
hen a compound-wound motor is employed, it is essential that the resistances should be gradually eliminated, in order that the current of full strength may not flow through the armature before the latter has attained a considerable velocity, and thereby generated in itself a counter-electro-motive force to oppose and weaken the actuating current. To accomplish this gradual elimination of the resistance, the cock 6' in the branch pipe 6 is so adjusted as to afford a small outlet for the water in the cylinder (7 causing the piston d to descend slowly, and thereby moving the lever (l gradually over the studs or buttons.
The resistances are cut out of circuit when the lever (Z is brought in contact with the stud 15, the velocity of rotation of the armature being then at its maximum and the circuit of the motor being completed through the line ll, the motor bein then a simple shunt-machine, a part of the current flowing through the primary field-coil 10. The motor continues to actuate the pump until the pressure in the tank B equals or exceeds the normal, and when this point is reached the valve e opens to operate the lever d, as above described, to break the circuit of the motor, substantially in an instant, and stop the rotation of its armature.
' I have thus far described the action of my improved system when a compound-wound motor is used; but I do not desire to limit myself to this particular type of motor, as a series motor maybe used equally well, and, when used, the resistances 2 -3 1 may be dispensed with and a simple switch employed.
Referring to Fig. l, the motor shown is a series motor, in which the negative line-wire is connected to one brush and the positive line-wire dto the lever d. In this instance the circuit of the motor is completed when the lever d co-operates with the contact-terminal f, to which one end of the field-wire 17 is connected. In this latter arrangement it will be understood that the fieldcoil forms a part of the main circuit, and the resistance of the said coil is suflicient to prevent injurious action when the motor is started.
I have herein shown the switch-lever operated by a pressure of a fluid upon a piston; but I do not desire to confine my invention to the use of a piston alone, as, instead of a piston, I may employ any well-known mechanical equivalentsuch, for instance, as a diaphragm having a co-operating rod or lever to actuate the said lever (Z; and, furthermore, I do not desire to limit myself to a switch made as a lever, as other usual forms of electric switch might be used, but I prefer the form shown.
I prefer to employ the relief-valve, as by it the regulator is moved with less shock than without it, yet I may entirely omit the reliefvalve and let the fluid at all times act directly upon the piston (Z and the system will operate practically; and so, also, I may employ the relief-valve itself for the regulator, the stem of the said relief-valve being operatively connected to the switch, as shown in Fig. 5.
I claim 1. In a hydraulic-elevator system, a regulater operated by changes in pressure of the fluid used to actuate the elevator, a pump, and an electric motor, combined with a switch controlled by the regulator to affect the circuit of the electric motor to start or stop the pump according to the pressure of the fluid employed, substantially as described.
2. In a system for actuating hydraulic elevators, the following instrumentalities, viz: a closed tank to contain a fluid under press- IIO ure, a pump to force the fluid into the said tank, and an electrically-actuated motor to operate the said pump at intervals, combined with a regulator under the control of the fluid under pressure in the tank, and with a switch to control the circuit of the electric motor, the said instrumentalities operating substantially as described.
3. In a system for actuating hydraulic elevators, a closed tank to contain a fluid under pressure, a pump to force the fluid into the said tank, and an electrically-actuated motor to operate the said pump at intervals, combined with a regulator under the control of the fluid under pressure in the tank, an d with a resistance and a lever co-operating therewith and controlled by the said regulator to affect the circuit of the electric motor, as and for the purpose specified.
4. In a system for actuating hydraulic elevators, a tank to contain a fluid under pressure, a pump, and an electric motor, a resistance and a lever co-operating therewith, and a piston connected to the said lever and actuated by fluid from the pressure-tank to move the said lever, combined with a relief-valve to control the fluid actuating the said piston, and with means, substantially as described, to move the piston in a direction opposite to that in which it is moved by the actuating-fluid, as and for the purpose specified.
5. In a system for actuating hydraulic elevators, a tank to contain a fluid under pressure, a pump, and an electric motor, a resistance and a lever co-operating therewith, a regulator in operative connection with the said lever, a pipe connecting said regulator with the pressure-tank, and a branch pipe forming a discharge-pipe for the said regulator, combined with a relief-valve to control the admission of fluid to the said regulator, and with a valve in the branch pipe to control the passage of fluid from the said regulator, as and for the purpose specified.
In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.
CHARLES WHITTIER.
Witnesses GEo. W. GREGORY, JAS. H. CHURCHILL.
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