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US790323A - Load-regulated starting and stopping device for elevators. - Google Patents

Load-regulated starting and stopping device for elevators. Download PDF

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Publication number
US790323A
US790323A US22002504A US1904220025A US790323A US 790323 A US790323 A US 790323A US 22002504 A US22002504 A US 22002504A US 1904220025 A US1904220025 A US 1904220025A US 790323 A US790323 A US 790323A
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valve
car
starting
load
elevator
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US22002504A
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Louis W Southgate
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66BELEVATORS; ESCALATORS OR MOVING WALKWAYS
    • B66B1/00Control systems of elevators in general
    • B66B1/24Control systems with regulation, i.e. with retroactive action, for influencing travelling speed, acceleration, or deceleration

Definitions

  • an elevator has to work anywhere within the extremes of four different conditions that is to say, suppose an elevator should be adjusted to operate correctly and accurately with a normal or selected load it may be called upon to operate under any one of four conditions-different therefrom, or as follows, using the word relatively with respect to said normal or selected load: First, the elevator may have to make an upward trip witha relatively light load; second, the elevator may have to make an upward trip with a relalight load; fourth, the elevator may have totively heavy load; third, the elevator may have to make a downward trip with a relatively ⁇ Image a downward trip with a relatively heavy
  • the present invention has particular reference to controlling the rate of movement of the starting and stopping device of an elevator, such as the main valve of a hydraulic elevator, to meet all conditions with the highest possible efliciency, and so that the operator simply has to throw his operating means for the operation desired, and the same will take place by the mechanism at the right speed. Now to operate in themost advantageous way the following should be the rates of movement of the starting and stopping device: I
  • This bounding often causes jar and derangement.- This fault is particularly encountered under this condition, as the car is apt to acquire a high speed going up with a light load.
  • the starting and stopping device should act quickly, both in starting and stopping, so that on the starting the full power will be applied rapidly, the heavy load resisting the violent start of the car and so that a quick stop will be obtained, the
  • T Vhile a slow action of the starting and stopping device for an upward movement of the car with a heavy load does not strain or effect the apparatus, it materially decreases the efliciency both in starting and stopping.
  • the starting and stopping device should operate quickly, both in starting and stopping, as the light load on the car will not put the car quickly in motion on the start down, and as a quick stop will not put aheavy strain on the apparatus as the momentum is not great.
  • a slow action of the starting and stopping device for a downward movement of the car with a light load materially decreases the efliciency of the mechanism both' in starting and stopping.
  • the starting and stopping device should act slowly, both in starting and stopping, so that the heavy load will not violently or quickly start the car on its downward movement, and so that when the car is stopped at the end of its downward movement the heavy load will be gradually brought to a state of rest.
  • a quick action of the starting and stopping device on a downward movement of the car with a heavy load will put the car violently and quickly in motion on the start and on the stop is apt to break or derange the parts owing to the rapid checking of the large momentum of the heavy load.
  • This last fault is especially encountered under this condition, as the car is apt to iii-cqiire a high speed going down witha heavy
  • This invention has been designed to provide a mechanism which will'cause the starting and stoppingdevice to operate at the right speed, both in starting and stopping, under these varying conditions, and to get the greatest possible passenger eiiiciency.
  • the motor for the elevator-car in such a device consists of a plunger running in a cylinder
  • the starting and stopping device consists of a three-way or so-called main valve.
  • the means for actuating the starting and stopping device or main valve may consist of a rope mechanism attached thereto and extending directly to the car; but in modern practice the main valveis operated by a supplemental motor controlled by a pilot-valve to which the rope mechanism is connected and which operates in a well-understood way.
  • the specific means illustrated to describe the invention consists in a device for controlling the voperative connection between the pilot-valve and the main valve so constructed and arranged thatevery starting and stopping movement of the main valve will take place at the same relative speed as between the starting and stopping movements, but so that each particular starting and stopping movement will be proportioned or adjusted in its rate of movement to the particular load.
  • the invention in this specific form consists in dividing the to-and-fro pipe from the pilotvalve to the main valve into two branches, one of which I term the up-pipe, and the other of which 1 term the down-pipe and in providing means for controlling or regulating the rate of flow through the up-pipe and through the down-pipe measured by the load.
  • This measuring effect is preferably obtained by using the pressure of the load in the cylinder through adjusting means to set the controlling device or devices. This pressure is preferably only allowed to work when the car is at rest and is shut off when the starting and stopping device commences to work and the carto go up or down, whereby the controlling or regulating device or devices are held in their adjusted position while the car is in motion.
  • Figure 1 is a perspective view of a plunger hydraulic elevator, showing the relative arrangement of parts.
  • Fig. 2 is a cross-sectional view through the valve mechanism with my improvement applied thereto.
  • Fig. 3 is a cross-sectional view illustrating the valve arrangement in the mechanism for admitting pressure to adjust the regulating device or devices.
  • Figs. 4 and 5 are views of the parts constituting the invention in a diti'erent position from that shown in Figs. 2 and 3.
  • Fig.6 is a sectional view of the pilotvalve, and
  • Fig. 7 is a detail view illustrating a modification.
  • A designates the plunger, B the cylinder, and C the car, which may have the usual counterweights W attached thereto by ropes trained over sheaves 9.
  • 1O designates adouble-standingcontrollingrope, the ends of which are trained over sheaves 11 at the top of the well and connected to weight 12.
  • the two strands of the rope pass downward, are crossed between the pulleys 13, arranged on a lever l i, carried by the car, and then pass down around sheaves 15 at the bottom of the well.
  • One strand of said rope is connected to the operating-lever 16.
  • a shaft is carried forward on the bottom of the car from the lever 14 and has a handle 17 extending into the car. This forms a means of ordinary construction for controlling the operating-lever 16 from the car.
  • the valve mechanism consists of a main valve M, a pilot-valve P, and a double automatic or shut-oil? valve S.
  • a pressure-pipe l8 and an exhaust-pipe 19 are connected to the main valve, and two pipes 20 and 21 connect the main valve and shut-off valve.
  • the shut-off valves connect by pipe 22 to cylinder B.
  • a piston 33 On the main-valve stem are arranged a piston 33, a valve 21, controlling the supply, an intermediate piston 25, a valve 26, controlling the exhaust, and a piston 27, so that when the main valve is moved to the left, prcssu re will flow in through pipe 18, connection 20, and pipe 22 to the clevator-eylinder, and so that when the main valve is moved to the right, cylinder B will exhaust through pipe 22, connection 21, and pipe 19.
  • the piston 23 is larger than the other pistons and valves.
  • the left-hand end of the main valve is connected by a to-and-fro pipe 28 to the pilotvalve at two points.
  • the pressure-pipe 18 is connected to the pilot-valve by a pipe 29, and the exhaust-pipe 19 is connected to the pilotvalve by a pipe 30.
  • the pilot-valve is made up of valves 31 and 32, an intermediate piston 33, and valves 34 and 35, valves 32 and 34 being used as an additional means to prevent leakage when the pilot-valve is in central position. These parts are arranged: so that when the pilot-val'veis lowered valves 34 and 35 are opened to connect the lower branch of.
  • the end of the rod 38 is connected by an arm 39 to the stem of the pilot-valve.
  • Said rod also carries a wide-faced pinion 40, engaging which is a rack 41, extending from the main-valve stem.
  • These parts are arranged so, that when the pilot-valve is moved down to cause the main valve to move to the left said rack 41 will turn said pinion40 and will cause the screw 37 to run into the nut 36, and thus to move and restore the pilot-valve to its central or normal position and so that when the pilot-valve is moved up to cause-a movement of the main valveto the right said screw will be unscrewed from the nut 36 and the pilotvalve restored to normal or central position.
  • the screw 37 and the pinion 40 can move axially to allow the pilot-valve to be moved from the operating-lever 16, the pinion 40 being made wide-faced for this purpose. It will also be noted that by means of this arrangement.
  • the rod 38 extends out through a partrigidly secured to the casing which has on its inner side a screw-cam or helix 42 and on its outer face another screw-cam or hBllX 43.
  • helix 42 ranged to face the helix 42, and also ahelix 45, arranged to face the helix 43.
  • These helices are formed to have the same pitch as the screw 37 and areset as shown in the drawings. This arrangement is used so as to prevent a careless operator on the car vlolently reversing the motion of the car.
  • valves are substantially rights and lefts, the right-hand valve being used to check and stopthe car at the limit of its downward run and the left-hand valve to check and stop the car at the limit of its'up ward run.
  • the right-hand one of said valves is operated by a running controlling-rope 48,
  • the shut-off valve S consists of two valves--- which is trained around a sheave mounted on a weighted arm connected to said valve and around suitable sheaves at the top and bottom of the well, the running controlling-rope point of attachment to the bottom of the car on an incline, so that the increasing angular de'flectionof said rope as the car reaches the bottom of its run will operate said valve.
  • the left-hand valve 49 is similarly actuated by a running controlling-rope 49, which has its point of attachment at the top of the car so arranged that the rope passes thereto from its overhead sheave on an incline.
  • the mechanism before described constitutes a plunger-elevator, a main valve, pilot-valve,
  • the invention is applied to the to-and-fro pipe 28, which ex- 7 7 tends from the pilot-valve to the motor means for thejmain valve, which motor means consists of the left-hand part of the main-valve casing and the piston 23. From the point60 intotwo branches 62 and 63, the branch 62 of which I term the uppipe and the branch 63 of which 1 term the down-pipe. By this arrangement a double or branch to-andfro pipe is obtained.
  • The'first part ofthe to-and-fro pipe 28 connects to a valve-casing 64, arranged in which is a turningplug 65, extendlngfromwhich1s a lever 66, which connects by link 67 to the projecting end of the valve-rod of the main valve, whereby said turning plug 65 will be operated by the movements of the main valve or by the motor means for the main valve.
  • the up and down pipes 62 and 63 connect to said valve-casing, as shown.- The main valve has considerable When the main valve is in- -to' the point 61 theto-and-fro pipe is divided into either the up or down pipe 62 or 63; but
  • a controlling means for regulating theflow vided The two, controlling means,one in'each .in each branch of the to-and-fro pipe is pro- &
  • the same consists of a casing 68, arranged in which is a valve-rod carrying two pistons 69 and 70.
  • the inlet and outlet are arranged to operate between these pistons.
  • a conical valve-seat 71 Between the inlet and outlet is arranged a conical valve 72 is adjustably secured on the valve-rod.
  • a tension means is arranged to keep the pistons in their lowest positions, the same consisting in Fig. 2 of a powerful spring 73, bearing on the top of the upper piston and on a cap 74:, which is threaded into said casing 68 and through which the rod passes. By adjusting the cap the tension of the spring can be regulated.
  • the left-hand controlling means which regulates the flow through the up-pipe 62, is the same as that previously described except that its conical valve-seat 710 and valve 720 are arranged the other way up relatively to the firstdeseribed mechanism.
  • the two outlet-pipes from said controlling means connect together at a point 61.
  • the two controlling means operate oppositely.
  • a pipe 75 is connected from the pipe 22, extending from the main valve to the elevator-cylinder, so as to let pressure under each of said pistons 69 69.
  • the flow through this pipe 7 5 is preferably directed through the valve-casing 64, a passage 76 being cut through the turning-plug 65, so as to allow the pressure to flow only when the main valve is in central position and to stop the flow when the main valve moves either way from its central position.
  • the right-hand valve 72 which controls the down-pipe, acts to restrict the flow through the down-pipe as the load increases, and that the left-hand valve 720 acts to allow a greater flow as the load increases.
  • These valves and their tension devices are adjusted so that with a normal or average load on the car they will allow the flow through the up and down pipes at a normal speed, so that the rate of movement of the starting and stopping device, both on its movement for starting the elevator and on its movement for stopping the elevator, will take place at the proper speed.
  • valves 7 2 and 7 20 will assume the position shown in Fig. 2 or a position proportioned thereto in the same measure as the load diminishes from normal to the lightest possible load.
  • the operator now through his rope mechanism lowers the lever 16 to the limit of its downward motion. This will allow an exhaust through pipe 28 and will cause the main valve to move to the left to start the car on its upward movement.
  • the flow between the pilot-valve and motor means will be directed through the up-pipe 62, and the flow being restricted the main valve will move slowly to its wide-open position, thus easily startingthe car.
  • valve 72 In this instance as the valve 72 is wide open the flow will be unrestricted and the main valve will move quickly and the car will be quickly put in motion. Vllhen a stop is desired, the operator will restore the lever 16 to its central position, which will connect the motor means with the exhaust, so that the main valve will return to its central position. As this flow is unrestricted, the main valve will move quickly and the car will be quickly stopped. Thus with a light load on the car the starting and stopping device will move slowly on its starting for an upward motion of the car,will move slowly for a stopping motion of the upward run, will move quickly for the starting motion on a downward run, and will move quickly for the stopping motion of a downward run. Now suppose that the car should be operated under the reverse condition-that is, with a heavy load. In this case the valves 72 and Y720 will assume the position shown in Fig. 1
  • valves 72 and 7 20 As the movement of the valves 72 and 7 20 is against spring 73 73.
  • Valves 77 and 78 are interposed in the up By looking the valve 72 in its lowest position and the valve 7 20 in its upper position these valves 77 and 78 may be used as controlling means in the -up or down pipes, and such arrangements -come within the scope of my claims.
  • valves 72 and 720 are to adjust the position of the valves 72 and 720 by the as the tension device for each of the valves 7 2 and 7 20, I pivot an arm on each casing 68, ad-
  • valves 77 and 78 are usefulwhen it is desired to adjust the valves 72 and 720 and are useful to cooperate with the said the rate of movement for a normal load.
  • a starting and stopping device for the motor therefor, a starting and stopping device for the motor, motor means for the starting and stopping device, valve mechanism for the motor means, and means for controlling the flow between the valve mechanism and the motor means constructed and arranged so that the starting and stopping device will have a quick starting and stopping action on a d ownward movement of the car with a light load.
  • a hydraulic-elevator valve mechanism the combination of a main valve, motor means therefor, a pilot-valve, a branched or. double connection between the pilot-valve and motor means forming an up-pipe and a downpipe, and means actuated by the main valve for directing the flow in one pipe for an upward movement of the elevator and in the other pipe for a downward movement of the elevator-car.
  • a hydraulic-elevator valve mechanism the combination of a main valve, motor means therefor, a pilot-valve, a branched or double toandfro connection between the pilot-valve and motor means, means for directing the flow in one pipe for an upward movement and in the other pipe for a downward movement of the elevator car, and means for controlling the flow in each branch of the to-and-fro pipe.
  • a hydraulic-elevator valve mechanism the combination of a main valve, motor means therefor, a pilot-valve, a branched or double to and fro connection between the pilot-valve and motor means, means for directing the flow in one pipe for an upward movement and in the other pipe for a downward movement, means for regulating the flow in each branch, and an automatic adjusting means for setting the controlling means.
  • a hydraulic-elevator valve mechanism the combination of a main valve, motor means therefor, a pilot-valve, a branched or double to andfro connection between the pilot-valve and motor means, means for directing the flow, controlling means for regulating the flow in each branch, and an automatic adjusting means, for the controlling means operated by the pressure from the load.
  • a hydraulic-elevator valve mechanism In a hydraulic-elevator valve mechanism, the combinationof a main valve, motor means therefor, a pilot-valve, a branched or adjusting means for the controlling means operated from the pressure due to the load and arranged to work oppositely on each controlling means.
  • a hydraulic-elevator valve mechanism the combination of a main valve, motor means therefor, a pilot-valve, a double or branched connection between the pilot-valve and the motor means, a valve operated by the main valve for directing the flow, a controlling-valve for regulating the flow in each branch, and a piston connected to each valve and exposed to pressure from the elevatorcylinder, said controlling-valves being oppositely arranged.
  • a hydraulic-elevator valve mechanism the combination of a main valve, motor means therefor, a pilot-valve, a branched to and-fro connection between the pilot-valve and motor means, a valve operated by the main valve for directing the flow, aspringpressed controlling-valve in each connection, and pistons exposed to the pressure due to the load for adjusting the controlling-valves oppositely.
  • a hydraulic-elevator valve mechanism the combination of a main valve, motor means therefor, a pilot-valve, a branched to and-fro connection between the pilot-valve and motor means, a valve operated by the main valve for directing the flow through the branches, a controlling-valve in each branch, a piston for operating each controlling-valve, a connection allowing the pressure of the load to operate on said pistons, and means for allowing said pressure to act when the main valve is in its central position and to cut the same off when the'main valve moves away from its central position.
  • a hydraulic-elevator valve mechanism the combination of a main valve, motor means therefor, a pilot-valve, a branched or double toand-fro connection between the pilot-valve and the motor means, a valve operated by the main valve for directing the flow, a controlling-valve in each branch, a piston for operating each controlling-valve, a connection for carrying the pressure due to connected to said casing so as to bebetween said p1stons,a valve-seat between said pistons, 1
  • a conical valve on said rod between the said pistons, a connection for allowing pressure from the elevator-cylinder to act on the outer side of one of said pistons, and a tension means operating in opposition to the pressure on the piston.

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Description

110.790.323. v PATENTEDMAY23,19O5. L. w. SOUTHGATE.
? LOAD REGULATED STARTING AND STOP-PING DEVICE FOR ELEVATORS.
APPLICATION FILED AUG. 8. 1904.
a SHEETS-SHEET 1.
No. 790,323. PATENTED MAY 23, 1905.
I L. W. SOUTHGATE. LOAi) REGULATED STARTING AND STOPPING DEVICE FOR ELEVATORS.
APPIJGATION FILED AUG. 8. 1904.
a SHEETS-SHEET z.
PATENTED MAY 23,1905.
-L. W; SOUTHGATE. I LOAD REGULATED STARTING AND STOPPING DEVICE FOR ELEVATORS.
APPLICATION FILED AUG. 8. 1904.
s SHEETS-SHEET a.
"(Z/Tlzrcesses:
UNITED STATES Patented May 23, 1905.
PATENT OFFICE.
LOAD-REGULATED STARTING AND STOPPING DEVICE FOR ELEVATORS.
SPECIFICATION forming part of Letters Patent N0. 790,323, dated May 23, 1905.
Application filed August 8, 1904. Serial No. 220,025.
To all whom it may concern:
Be it known that 1, Louis W. SOUTHGATE, a
citizen of the United States, residing at W'orcester, in the county of Worcester and State of Massachusetts, have invented a new and useful Load-Regulated Starting and Stopf ping Device for Elevators, of which the following is a specification,
In designing modern elevators two conflicting conditions are'encountered: First, the elevator must be run at as high a speed as is possible to get the greatest passenger eflicicncy, and, second, the apparatus must be designed so as to be safe under all conditions and safe independent of the skill of the op erator. This has led to complications, be-
cause an elevator has to work anywhere within the extremes of four different conditions that is to say, suppose an elevator should be adjusted to operate correctly and accurately with a normal or selected load it may be called upon to operate under any one of four conditions-different therefrom, or as follows, using the word relatively with respect to said normal or selected load: First, the elevator may have to make an upward trip witha relatively light load; second, the elevator may have to make an upward trip with a relalight load; fourth, the elevator may have totively heavy load; third, the elevator may have to make a downward trip with a relatively {Image a downward trip with a relatively heavy The present invention has particular reference to controlling the rate of movement of the starting and stopping device of an elevator, such as the main valve of a hydraulic elevator, to meet all conditions with the highest possible efliciency, and so that the operator simply has to throw his operating means for the operation desired, and the same will take place by the mechanism at the right speed. Now to operate in themost advantageous way the following should be the rates of movement of the starting and stopping device: I
First. 1 For an upward movement of the car with a light load the stopping device should .act slowly, both in starting and in stopping, for if it were possible underthis condition to start the car quickly a violent jolt will be imparted to the passengers, because the car is brought up to full speed in a very short movement, as the motor is not materially op posed by the light load; and if it werepossible to stop the car quickly after full speed has been acquired the car will run a considerable distance by its momentum and by the momentum of its counterweights, so that it will bound, as it is called,which occurs in ropeelevators by the car jumping up on the ropes and then dropping back, or in hydraulic elevators by the piston or plunger leaving the water in the cylinder and then dropping back.
This bounding often causes jar and derangement.- This fault is particularly encountered under this condition, as the car is apt to acquire a high speed going up with a light load.
Second. For an upward movement of the car with a heavy load the starting and stopping device should act quickly, both in starting and stopping, so that on the starting the full power will be applied rapidly, the heavy load resisting the violent start of the car and so that a quick stop will be obtained, the
heavy load preventing any abnormal runor bound of the car. T Vhile a slow action of the starting and stopping device for an upward movement of the car with a heavy load does not strain or effect the apparatus, it materially decreases the efliciency both in starting and stopping.
Third. For a downward movement of the car with alight load the starting and stopping device should operate quickly, both in starting and stopping, as the light load on the car will not put the car quickly in motion on the start down, and as a quick stop will not put aheavy strain on the apparatus as the momentum is not great. A slow action of the starting and stopping device for a downward movement of the car with a light load materially decreases the efliciency of the mechanism both' in starting and stopping.
Fourth. For a downward movement of the car with a heavy load the starting and stopping device should act slowly, both in starting and stopping, so that the heavy load will not violently or quickly start the car on its downward movement, and so that when the car is stopped at the end of its downward movement the heavy load will be gradually brought to a state of rest. A quick action of the starting and stopping device on a downward movement of the car with a heavy load will put the car violently and quickly in motion on the start and on the stop is apt to break or derange the parts owing to the rapid checking of the large momentum of the heavy load. This last fault is especially encountered under this condition, as the car is apt to iii-cqiire a high speed going down witha heavy This invention has been designed to provide a mechanism which will'cause the starting and stoppingdevice to operate at the right speed, both in starting and stopping, under these varying conditions, and to get the greatest possible passenger eiiiciency.
While the invention is capable of application to almost any style of elevator, the same will be further described as applied to a hydraulic elevator, a plunger hydraulic elevator being selected for the purpose of explanation. As is well understood, the motor for the elevator-car in such a device consists of a plunger running in a cylinder, and the starting and stopping device consists of a three-way or so-called main valve. The means for actuating the starting and stopping device or main valve may consist of a rope mechanism attached thereto and extending directly to the car; but in modern practice the main valveis operated bya supplemental motor controlled by a pilot-valve to which the rope mechanism is connected and which operates in a well-understood way.
The specific means illustrated to describe the invention consists in a device for controlling the voperative connection between the pilot-valve and the main valve so constructed and arranged thatevery starting and stopping movement of the main valve will take place at the same relative speed as between the starting and stopping movements, but so that each particular starting and stopping movement will be proportioned or adjusted in its rate of movement to the particular load.
The invention in this specific form consists in dividing the to-and-fro pipe from the pilotvalve to the main valve into two branches, one of which I term the up-pipe, and the other of which 1 term the down-pipe and in providing means for controlling or regulating the rate of flow through the up-pipe and through the down-pipe measured by the load. This measuring effect is preferably obtained by using the pressure of the load in the cylinder through adjusting means to set the controlling device or devices. This pressure is preferably only allowed to work when the car is at rest and is shut off when the starting and stopping device commences to work and the carto go up or down, whereby the controlling or regulating device or devices are held in their adjusted position while the car is in motion.
The device in its present form is shown in the accompanying three sheets of drawings, referring to which Figure 1 is a perspective view of a plunger hydraulic elevator, showing the relative arrangement of parts. Fig. 2 is a cross-sectional view through the valve mechanism with my improvement applied thereto. Fig. 3 is a cross-sectional view illustrating the valve arrangement in the mechanism for admitting pressure to adjust the regulating device or devices. Figs. 4 and 5 are views of the parts constituting the invention in a diti'erent position from that shown in Figs. 2 and 3. Fig.6 is a sectional view of the pilotvalve, and Fig. 7 is a detail view illustrating a modification.
In detail, A designates the plunger, B the cylinder, and C the car, which may have the usual counterweights W attached thereto by ropes trained over sheaves 9.
1O designates adouble-standingcontrollingrope, the ends of which are trained over sheaves 11 at the top of the well and connected to weight 12. The two strands of the rope pass downward, are crossed between the pulleys 13, arranged on a lever l i, carried by the car, and then pass down around sheaves 15 at the bottom of the well. One strand of said rope is connected to the operating-lever 16. A shaft is carried forward on the bottom of the car from the lever 14 and has a handle 17 extending into the car. This forms a means of ordinary construction for controlling the operating-lever 16 from the car.
The valve mechanism consists of a main valve M, a pilot-valve P, and a double automatic or shut-oil? valve S. A pressure-pipe l8 and an exhaust-pipe 19 are connected to the main valve, and two pipes 20 and 21 connect the main valve and shut-off valve. The shut-off valves connect by pipe 22 to cylinder B. On the main-valve stem are arranged a piston 33, a valve 21, controlling the supply, an intermediate piston 25, a valve 26, controlling the exhaust, and a piston 27, so that when the main valve is moved to the left, prcssu re will flow in through pipe 18, connection 20, and pipe 22 to the clevator-eylinder, and so that when the main valve is moved to the right, cylinder B will exhaust through pipe 22, connection 21, and pipe 19. The piston 23 is larger than the other pistons and valves. The left-hand end of the main valve is connected by a to-and-fro pipe 28 to the pilotvalve at two points. The pressure-pipe 18 is connected to the pilot-valve by a pipe 29, and the exhaust-pipe 19 is connected to the pilotvalve by a pipe 30. The pilot-valve is made up of valves 31 and 32, an intermediate piston 33, and valves 34 and 35, valves 32 and 34 being used as an additional means to prevent leakage when the pilot-valve is in central position. These parts are arranged: so that when the pilot-val'veis lowered valves 34 and 35 are opened to connect the lower branch of.
the to-and-fro pipe 28 to the exhaust-pipe 30, and hence to relieve the pressure at the left of the piston 23 to cause the main valve to move to the left and so that when the -pilotvalve is raised valves 31 and 32 are opened to right.
casing. The end of the rod 38 is connected by an arm 39 to the stem of the pilot-valve. Said rod also carries a wide-faced pinion 40, engaging which is a rack 41, extending from the main-valve stem. These parts are arranged so, that when the pilot-valve is moved down to cause the main valve to move to the left said rack 41 will turn said pinion40 and will cause the screw 37 to run into the nut 36, and thus to move and restore the pilot-valve to its central or normal position and so that when the pilot-valve is moved up to cause-a movement of the main valveto the right said screw will be unscrewed from the nut 36 and the pilotvalve restored to normal or central position. The screw 37 and the pinion 40 can move axially to allow the pilot-valve to be moved from the operating-lever 16, the pinion 40 being made wide-faced for this purpose. It will also be noted that by means of this arrangement.
whatever movement is given to the pilot-valve will be proportionately given to the main valve and that this movement of the main valve restores the pilot-valve to central posi tion. This forms a compact and efiicient pilot-valve mechanism.
The rod 38 extends out through a partrigidly secured to the casing which has on its inner side a screw-cam or helix 42 and on its outer face another screw-cam or hBllX 43.
.Rigidly secured to the rod 38 is a helix44, ar-
ranged to face the helix 42, and also ahelix 45, arranged to face the helix 43. These helices are formed to have the same pitch as the screw 37 and areset as shown in the drawings. This arrangement is used so as to prevent a careless operator on the car vlolently reversing the motion of the car.
one, 46, arranged between the pipes20 and 22 to control the pressure and the other, 47, between the pipe 21 and pipe 22 to control the exhaust. The valves are substantially rights and lefts, the right-hand valve being used to check and stopthe car at the limit of its downward run and the left-hand valve to check and stop the car at the limit of its'up ward run. v The right-hand one of said valves is operated by a running controlling-rope 48,
' passing from the sheaves at the bottom to its "lap' in practice. its central position, as shown in Fig. 2, the pressure from the to-and-fro pipe can start The shut-off valve S consists of two valves--- which is trained around a sheave mounted on a weighted arm connected to said valve and around suitable sheaves at the top and bottom of the well, the running controlling-rope point of attachment to the bottom of the car on an incline, so that the increasing angular de'flectionof said rope as the car reaches the bottom of its run will operate said valve.
The left-hand valve 49 is similarly actuated by a running controlling-rope 49, which has its point of attachment at the top of the car so arranged that the rope passes thereto from its overhead sheave on an incline.
The mechanism before described constitutes a plunger-elevator, a main valve, pilot-valve,
and safety-valve apparatus, which is now of well-knowntype and is being successfully installed, and I have chosen this form of apparatus to illustrate the, application of my invention to a modern elevatorof the most approved type.
In the present arrangement the invention is applied to the to-and-fro pipe 28, which ex- 7 7 tends from the pilot-valve to the motor means for thejmain valve, which motor means consists of the left-hand part of the main-valve casing and the piston 23. From the point60 intotwo branches 62 and 63, the branch 62 of which I term the uppipe and the branch 63 of which 1 term the down-pipe. By this arrangement a double or branch to-andfro pipe is obtained. The'first part ofthe to-and-fro pipe 28 connects to a valve-casing 64, arranged in which is a turningplug 65, extendlngfromwhich1s a lever 66, which connects by link 67 to the projecting end of the valve-rod of the main valve, whereby said turning plug 65 will be operated by the movements of the main valve or by the motor means for the main valve. The up and down pipes 62 and 63 connect to said valve-casing, as shown.- The main valve has considerable When the main valve is in- -to' the point 61 theto-and-fro pipe is divided into either the up or down pipe 62 or 63; but
just so soon as the main valve starts one or the other of said pipes will be-cut off and the flow will be directed into one pipe alone, the turning plug and 1ts actuating mechanism thus constituting a means for directlng the flow.
When the main valve moves from its central position to the left to allow pressure to flow to the elevator-cylinder toraise the car, they flow will be directed through the up=pipe 62,- and when the main valvemoves from its central position to the right to allow the exhaust to flow from the elevator-cylinder and the car to descend the flow will be directed through the down-pipe 63. a
A controlling means for regulating theflow vided. The two, controlling means,one in'each .in each branch of the to-and-fro pipe is pro- &
of said pipes, are substantially the same, except as hereinafter pointed out, and the righthand one, arranged in the down-pipe 63, will be described. The same consists of a casing 68, arranged in which is a valve-rod carrying two pistons 69 and 70. The inlet and outlet are arranged to operate between these pistons. Between the inlet and outlet is arranged a conical valve-seat 71. A conical valve 72 is adjustably secured on the valve-rod. A tension means is arranged to keep the pistons in their lowest positions, the same consisting in Fig. 2 of a powerful spring 73, bearing on the top of the upper piston and on a cap 74:, which is threaded into said casing 68 and through which the rod passes. By adjusting the cap the tension of the spring can be regulated.
The left-hand controlling means, which regulates the flow through the up-pipe 62, is the same as that previously described except that its conical valve-seat 710 and valve 720 are arranged the other way up relatively to the firstdeseribed mechanism. The two outlet-pipes from said controlling means connect together at a point 61. By this arrangement it will be seen that the two controlling means operate oppositely. For the adjusting means for said controlling means a pipe 75 is connected from the pipe 22, extending from the main valve to the elevator-cylinder, so as to let pressure under each of said pistons 69 69. The flow through this pipe 7 5 is preferably directed through the valve-casing 64, a passage 76 being cut through the turning-plug 65, so as to allow the pressure to flow only when the main valve is in central position and to stop the flow when the main valve moves either way from its central position. By this arrangement as the passengers get on or get off the car when it is at rest or as the load is taken on or put ofl as the car is at rest the pressure of the load will work through said pipe 7 5 and set the two controlling means or devices a distance proportional to or measured by the load and so that as the main valve moves in either direction from its central position to start the car either up or down the turning-plug 65 will cut the pistons 69 06? from the pressure in the elevator-cylinder and will hold them in their adjusted positions until the car is stopped by the main valve coming back to its central position. This forms an accurate adjusting means,because the pressure operating the piston 69 is that due to the load, and the pistons I 69 69 are not subject to the fluctuations of pressure in the elevator-cylinder as the water flows therein under pressure or exhausts therefrom.
It will be seen that the right-hand valve 72, which controls the down-pipe, acts to restrict the flow through the down-pipe as the load increases, and that the left-hand valve 720 acts to allow a greater flow as the load increases. These valves and their tension devices are adjusted so that with a normal or average load on the car they will allow the flow through the up and down pipes at a normal speed, so that the rate of movement of the starting and stopping device, both on its movement for starting the elevator and on its movement for stopping the elevator, will take place at the proper speed.
Suppose now that a light load is put upon the car. The valves 7 2 and 7 20 will assume the position shown in Fig. 2 or a position proportioned thereto in the same measure as the load diminishes from normal to the lightest possible load. Suppose the operator now through his rope mechanism lowers the lever 16 to the limit of its downward motion. This will allow an exhaust through pipe 28 and will cause the main valve to move to the left to start the car on its upward movement. Now so soon as the main valve starts on its movement the flow between the pilot-valve and motor means will be directed through the up-pipe 62, and the flow being restricted the main valve will move slowly to its wide-open position, thus easily startingthe car. Now when the operator moves the lever 16 back to central position to stop the ear pressure will be admitted from the pilot-valve through the to-and-fro pipe to the motor means to move the main valve back to its central position to stop the car. This flow must also take place through the up-pipe 62, and hence must take place at a restricted speed, whereby the main valve will move slowly back to its central position and the car will be slowly brought to a state of rest. Suppose now the operator moves the lever 16 up to the limit of its upward movement for a downward movement of the car. Pressure will be admitted through the to-and-fro pipe to cause the main valve to move from its central position to the right. As soon as the main valve starts the up-pipe 62 will be cut elf and the flow will be directed through the down-pipe 63. In this instance as the valve 72 is wide open the flow will be unrestricted and the main valve will move quickly and the car will be quickly put in motion. Vllhen a stop is desired, the operator will restore the lever 16 to its central position, which will connect the motor means with the exhaust, so that the main valve will return to its central position. As this flow is unrestricted, the main valve will move quickly and the car will be quickly stopped. Thus with a light load on the car the starting and stopping device will move slowly on its starting for an upward motion of the car,will move slowly for a stopping motion of the upward run, will move quickly for the starting motion on a downward run, and will move quickly for the stopping motion of a downward run. Now suppose that the car should be operated under the reverse condition-that is, with a heavy load. In this case the valves 72 and Y720 will assume the position shown in Fig. 1
or a position proportioned thereto in the same measure as the load increases from normal to the heaviest possible load, and without describing the operation in detail it will be seen that the flow through the up-pipe is unrestricted, while the flowthrough the do-Wn' pipe is restricted, whereby the main valve will move quickly both in starting and in stopping the elevator-car on its upward run and will move slowly both in starting and stopping the elevator-car on a downward run. The terms quickly and slowly have been used relatively to the normal load. Thus all the operator has to do to start or stop the car 5 ing-lever from its central position over to the extreme of its'travel, and the mechanism will under any condition is to throw his operatperform its operation at proper speed. The
- improvement does not interfere in any way with a partial startingor stopping movement of the main valve, as the pilotvalve still keeps control of the amount of movement of the main valve, and hence the car is still withf in the direction of the operator obtained by manipulation of the handle. By the tension device before described the rate of movement will be directlyproportional to the load itself,
as the movement of the valves 72 and 7 20 is against spring 73 73.
By the device described herein not only will the rate of movement of the main valve be controlled to operate under ideal conditions,
\ but it will be adjusted in such manner as to have its rate of movement directly propori and down pipes 62 and 63.
' tional to the load.
Valves 77 and 78 are interposed in the up By looking the valve 72 in its lowest position and the valve 7 20 in its upper position these valves 77 and 78 may be used as controlling means in the -up or down pipes, and such arrangements -come within the scope of my claims.
The
' preferred arrangement, however, is to adjust the position of the valves 72 and 720 by the as the tension device for each of the valves 7 2 and 7 20, I pivot an arm on each casing 68, ad-
- its moment becomes greater, and it consti- -valves to measure or determine load. The valves 77 and 78 are usefulwhen it is desired to adjust the valves 72 and 720 and are useful to cooperate with the said the rate of movement for a normal load.
In some instances, instead of using a spring justably mount a weight on each arm, and connect the valve-rod to said arm by a link 81. As the weight is thus swung upwardly tutes an accurate tension device for causing the valves 72 and 720 to assume a position from the pressure in pipe 75 corresponding to the load or pressure in the elevator-cylinder.
As I believe this invention covers a radically new and important method of controlling an elevator starting and stopping device, I wish it distinctly understood that the invention is not limited in its broad sense or in its broad claims to the specific means, valves, and connections herein described, as many other forms of mechanisms may be worked out to utilize the invention withoutdeparting from the scope of the claims.
Having thus fully described my invention, what I claim, and desire to secure by Letters Patent, is-
1. The combination of an elevator-car, a motor therefor, a starting and stopping device for the motor, and controlling means adjusted by the load on the car for regulating the rate of movement of the starting and stopping device constructed and arranged so that the rate will be the same in starting and in stopping.
2. The combination of an elevator-car, a motor therefor, a starting and stopping device for the motor, and controlling means for regulating the rate of movement of the starting and stopping device constructed and arranged so that the same will have a quick starting and stopping action on an upward movement of the car with a heavy load.
3. The combination of an elevator-car, a motor therefor, a starting and stopping device for the motor, and controlling means for regulating the rate of movement of the starting and stopping device constructed and arranged so that the same will have a slow starting and stopping action on an upward movement of the car with a light load.
4. The combination of an elevator-car, a mo tor therefor, a starting and stopping device for the motor, and controlling means for regulating the rate of movement of the starting and stopping device constructed and arranged so that the. same will have a quick starting and stopping action on an upward movement 'of the car with a heavy load and so that the same will have a slow starting and stopping action on an upward movement of the car with a light load.
5. The combination of an elevator-car, amotor therefor, a starting and stopping device for the motorand controlling means for regulating the rate of movement of the starting and stopping device constructed and arranged so that the same will have a quick starting and stop ping actlon on a downward movement of the car with a light load.
6. The combination of an elevator-car, amotor therefor,a starting and stopping device for the motor, and controlling means for regulating the rate of movement of the starting I and stopping device constructed and arranged so that the same will have a slow startingand' stopping action on a downward movement of the car with a heavy load.
7. The combination of an elevator-car, amotor therefor, a starting and stopping device for the motor, and controlling means-for regulating the rate of movement of the starting and stopping device constructed and arranged so that the same will have a quick starting and stopping action on a downward movement of the car with a light load and a slow starting and stopping action on a downward movement of the car with a heavy load.
8. The combination of an elevator-car, a motor therefor, a starting and stopping device for the motor, and controlling means for regulating the rate of movement of the starting and stopping device constructed and arranged so that the same will have a slow starting and stopping action on an upward movement of the car with a light load; so that the same will have a quick starting and stopping action on an upward movement of the car with a heavy load; so that the same will have aquick starting and stopping action on a downward movement of the car with a light load; and so that the same will have a slow starting and stopping action on a downward movement of the car with a heavy load.
9. The combination of an elevator-car, a motortherefor, astarting and stopping device for the motor, motor means for the starting and stopping device, a valve mechanism for the motor means, and means for controlling the flow between the valve mechanism and motor means adjusted by the load of the car constructed and arranged so that the flow will be under similar conditions in starting and in stopping.
10. The combination of an elevator-car, a motor therefor, a starting and stopping devicefor the motor, motor means for the starting and stopping device, valve mechanism for the motor means, and means for controlling the flow between the valve mechanism and the motor means constructed and arranged so that the starting and stopping device will have a quick starting and stopping action on an upward movement of the car with a heavy load.
11. The combination of an elevator-car, a motor therefor, a starting and stopping device for the motor, motor means for the starting and stopping device, valve mechanism for the motor means, and means for controlling the flow between the valve mechanism and the motor means constructed and arranged so that the starting and stopping device will have a slow starting and stopping action on an upward movement of the car with a light load.
12. The combination of an elevator-car, a motor therefor, a starting and stopping device for the motor, motor means for the starting and stopping device, valve mechanism for the motor means, and means for controlling the flow between the valve mechanism and the motor means constructed and arranged so that the starting and stopping device will have a quick starting and stopping action on an upward movement of the car with a heavy load and so that the starting and stopping device will have a slow starting and stopping action on an upward movement of the car with a light load.
13. The combination of an elevator-car, a
motor therefor, a starting and stopping device for the motor, motor means for the starting and stopping device, valve mechanism for the motor means, and means for controlling the flow between the valve mechanism and the motor means constructed and arranged so that the starting and stopping device will have a quick starting and stopping action on a d ownward movement of the car with a light load.
1 The combination of an elevator-car, a motor therefor, a starting and stopping device for the motor, motor means for the starting and stopping device, valve mechanism for the motor means, and means for controlling the flow between the valve mechanism and the motor means constructed and arranged so that the starting and stopping device will have a slow starting and stopping action on a downward movement of the car with a heavy load.
15. The combination of an elevator-car, a motor therefor, a starting and stopping device for the motor, motor means for the starting and stopping device, valve mechanism for the motor means, and means for controlling the flow between the valve mechanism and the motor means constructed and arranged so that the starting and stopping device will have a quick starting and stopping action on a downward movement of the car with a light load, and a slow starting and stopping action on a downward movement of the car with a heavy load.
16. The combination of an elevator-car, a motor therefor, a starting and stopping device for the motor, motor means for the starting and stopping device, valve mechanism for the motor means, and means for controlling the flow between the valve mechanism and the motor means constructed and arranged so that the starting and stopping device will have a quick starting and stopping action on an upward movement of the car with a heavy load, a slow starting and stopping action on an upward movement of the car with a light load, a quick starting and stopping action on a downward movement of the car with a light load and a slow starting and stopping action on a downward movement of the car with a heavy load.
17. The combination of an elevator-car, a motor therefor, a starting and stopping device for the motor, motor means for the starting and stopping device, a pilot-valve for the motor means, and a double connection between the pilot-valve and motor means, said connection comprising provision in virtue of which the flow will take place through one branch for a starting and stopping movement of the starting and stopping device for an upward movement of the car, and in virtue of which the flow will take place through the other branch for a starting and stopping movement of the starting and stopping device for a downward movement of the car.
18. The combination of an elevator-car, a hydraulic motor therefor, a main valve, motor means therefor, a pilot-valve, a double or branched to-and-fro pipe between the pilotvalve and motor means, and means for directing the flow through one branch for a starting and stopping of an upward movement of the elevator-car, and through the other branch for astarting and stopping of a downward movement of the elevator-car.
19. In a hydraulic-elevator valve mechanism, the combination of a main valve, motor means therefor, a pilot-valve, a branched or. double connection between the pilot-valve and motor means forming an up-pipe and a downpipe, and means actuated by the main valve for directing the flow in one pipe for an upward movement of the elevator and in the other pipe for a downward movement of the elevator-car.
20. In a hydraulic-elevator valve mechanism, the combination of a main valve, motor means therefor, a pilot-valve, a branched or double toandfro connection between the pilot-valve and motor means, means for directing the flow in one pipe for an upward movement and in the other pipe for a downward movement of the elevator car, and means for controlling the flow in each branch of the to-and-fro pipe.
21. In a hydraulic-elevator valve mechanism, the combination of a main valve, motor means therefor, a pilot-valve, a branched or double to and fro connection between the pilot-valve and motor means, means for directing the flow in one pipe for an upward movement and in the other pipe for a downward movement, means for regulating the flow in each branch, and an automatic adjusting means for setting the controlling means.
22. In a hydraulic-elevator valve mechanism, the combination of a main valve, motor means therefor, a pilot-valve, a branched or double to andfro connection between the pilot-valve and motor means, means for directing the flow, controlling means for regulating the flow in each branch, and an automatic adjusting means, for the controlling means operated by the pressure from the load.
23. The combination in a hydraulic-elevator valve mechanism, of a main valve, motor means therefor, a pilot-valve, a branched or double to andfro connection between the pilot-valve and motor means, means for directing the flow in one pipe for an upward movement and in the other pipe for a downward movement, a controlling means in each branch for regulating the flow, and an adjusting means operated by the load on the car arranged to operate the two controlling means oppositely. v
24:. In a hydraulic-elevator valve mechanism, the combinationof a main valve, motor means therefor, a pilot-valve, a branched or adjusting means for the controlling means operated from the pressure due to the load and arranged to work oppositely on each controlling means.
25. The combination in a hydraulic-elevator valve mechanism, of a main valve, motor means therefor, a pilot-valve, a branched or double to and fro connection between the pilot-valve and motor means, a controlling means in each branch for regulating the flow, an adjusting means operated by the load on the car arranged to operate the two controlling means oppositely, and means whereby this adjusting mechanism will only act when the main valve is in its central or closed position.
26. In a hydraulic-elevator valve mechanism, the combination of a main valve, motor means therefor, a pilot-valve, a double or branched connection between the pilot-valve and the motor means, a valve operated by the main valve for directing the flow, a controlling-valve for regulating the flow in each branch, and a piston connected to each valve and exposed to pressure from the elevatorcylinder, said controlling-valves being oppositely arranged.
27. In a hydraulic-elevator valve mechanism, the combination of a main valve, motor means therefor, a pilot-valve, a branched to and-fro connection between the pilot-valve and motor means, a valve operated by the main valve for directing the flow, aspringpressed controlling-valve in each connection, and pistons exposed to the pressure due to the load for adjusting the controlling-valves oppositely.
28. In a hydraulic-elevator valve mechanism, the combination of a main valve, motor means therefor, a pilot-valve, a branched to and-fro connection between the pilot-valve and motor means, a valve operated by the main valve for directing the flow through the branches, a controlling-valve in each branch, a piston for operating each controlling-valve, a connection allowing the pressure of the load to operate on said pistons, and means for allowing said pressure to act when the main valve is in its central position and to cut the same off when the'main valve moves away from its central position.
29. In a hydraulic-elevator valve mechanism, the combination of a main valve, motor means therefor, a pilot-valve, a branched or double toand-fro connection between the pilot-valve and the motor means, a valve operated by the main valve for directing the flow, a controlling-valve in each branch, a piston for operating each controlling-valve, a connection for carrying the pressure due to connected to said casing so as to bebetween said p1stons,a valve-seat between said pistons, 1
a conical valve on said rod between the said pistons, a connection for allowing pressure from the elevator-cylinder to act on the outer side of one of said pistons, and a tension means operating in opposition to the pressure on the piston.
In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.
LOUIS \V. SOUlHGAlE. Witnesses:
PHILIP \V. SoU'riIoA'rw, .ANGIE M. GODDARD.
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