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US1991000A - Automatic leveling mechanism for hydraulic motors, elevators, etc. - Google Patents

Automatic leveling mechanism for hydraulic motors, elevators, etc. Download PDF

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US1991000A
US1991000A US621504A US62150432A US1991000A US 1991000 A US1991000 A US 1991000A US 621504 A US621504 A US 621504A US 62150432 A US62150432 A US 62150432A US 1991000 A US1991000 A US 1991000A
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car
valve
control
floor
elevators
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US621504A
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John A Rogers
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Hydraulic Elevator and Machine Co Inc
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Hydraulic Elevator and Machine Co Inc
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66BELEVATORS; ESCALATORS OR MOVING WALKWAYS
    • B66B1/00Control systems of elevators in general
    • B66B1/34Details, e.g. call counting devices, data transmission from car to control system, devices giving information to the control system
    • B66B1/36Means for stopping the cars, cages, or skips at predetermined levels
    • B66B1/40Means for stopping the cars, cages, or skips at predetermined levels and for correct levelling at landings
    • B66B1/405Means for stopping the cars, cages, or skips at predetermined levels and for correct levelling at landings for hydraulically actuated elevators
    • 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

Definitions

  • This invention relates toautomaticlevelin mechanism for hydraulic motors, elevatcrs, etc and has particular reference. tomeans-whereby a hydraulic motor, andimore particularly a di-r' rect hydraulic plunger elevator can be held auto matically at a floorlevel, when the' control lever is 1at neutral position:
  • Towcontrolthe ac-l tuating motor or, motors actuating the main exhaust and'supply :valve is a pilot valve; which in turn is connected-by oables to the, lever,in,the
  • I provide an auxiliary supply and exhaust valves connectedto the to-and-irom pipe and automatically control these one or more floors where, it is desired to automatically level the car. If the car tends to drop away from the floor, it, through thefhatchway connections, will open the auxiliary supply valve andca'dmit pressure to-the to rise ,from the' floor as by, leakage. of "supply pressure into .the'cylinder, a'similardevice will i open the "auxiliary exhaust valve and let the excess pressure outof, the cylinder, While either as thereby, with proper spacing of the hatchway devices at" the "floor or floors, the. elevator can only move a.slightldistancelfrom resting position without bringing itself back v v
  • the hatchway devices are actuated by a withdrawable connection to" the car control lever,
  • l5-- is the to-and-from pipeconnected at the top of cylinder 1.
  • 16 isthe 14 are automatic end stop valves which notch in the car quadrant receiving spring actuated bolt 1'7 on the car lever, which bolt is drawn against the spring by the hand of the operator and when he lets go, either rides on the quadrant or drops nto the notch 16 when the car lever is put into neutral position.
  • auxiliary supply side for 1 bringing the car back 'to'the floor when it has dropped below 20 represents a" pressure pipe ,stappe d from supply 6 and connected to valve casingf2l containing a reciprocatingported plug valve 22 (see Fig. 3).
  • This supply pressure passesfrom valve casing 21 through pipe 23 to an auxiliary to-and-from pipe 24 connected to main to-andefrorn' pipe 15.
  • a link 26 To stem 25 of valve 22 is conneoted a link 26 which in turn is connected to lever 27 pivoted at 28. carrying a weight 29.
  • lever 27 To end of lever 27 is a flexible connection such; as
  • A'similar mechanism is provided for the exhaust side comprising exhaust pipe 36, exhaust valve casing 37, exhaust valve 38, exhaust pipe 39 leading to auxiliaryto-and-from'pipe 2a.
  • link 40, lever 41,weight 42, chain 43, running over pulleys, 44,145 connected to a second fiat Q steel tape46 extending up the hatchwayparallel to tape 33 and, suspended at the'top of the build ing by a weight running over a pulley, or a spring to counterfbalance'them and hold them under proper tension, are provided for actuating the auxiliary exhaust valve.
  • lB is a non-return check valve in supply pipe 23, and 49 is a similar valve in exhaust pipe 391 50, 51 are independently adjustable set cooks for controlling the rate offlow in'the respective supply and exhaust pipes 23, 39, to determine the speed of returning the car to level position.
  • v is a non-return check valve in supply pipe 23, and 49 is a similar valve in exhaust pipe 391 50, 51 are independently adjustable set cooks for controlling the rate offlow in'the respective supply and exhaust pipes 23, 39, to determine the speed of returning the car to level position.
  • valves 22, 38 are similarly constructed, beingexternally cylindrical and internally hollowed on a taper as shown, with sets of ports 52,v
  • cams are mounted on aparallel linkage as shown, and when pressed outwardly of the car, or to the left in Fig. 2, lift their respective steel tape 33 or 46. This is effected by blocks 57, 58 mounted on tapes 33,46 respectively, so that when the cams 55 or 56 are pushed in, as by rollers-60 on the car, the levers 61, 62 are lifted and in engaging blocks 57, 58, liftthe respective tape 33or 46 and thereby open the corresponding auxiliary supply or exhaust valve.
  • roller- 60 Passing" now to 'the car mechanism, roller- 60 before mentioned, is mounted on block 67 sliding on a suitable trackwayfifi beneath the" car, and block 6'7; is-connected by red 68 to a second similarly mounted block 69.
  • a link '70 To block 69 is pivoted a link '70 which latter is pivoted to arm '71 rigidly mounted. on controller lever shaft 12.
  • the link '70 and arm '71 constitute a linkage, when ver is in neutral position, forms a thrust mecha nism to projectthe roller 60 into the path of the cams. This is some seconds before the car actually stops, because time is required after the operator brings the car lever-to center and opens the pilot valve to close the main valve for the main valve to close, and in doing so, automatically close the pilot valve.
  • roller 60 comes to rest between cams 55, 56. If the car stops too soon, being below the floor, then the roller 60 through cam 55- and block 57 1lftS tape 33 and opens auxiliary supply valve 22. Likewise, if the car has once stopped at the floor andsinks because of.
  • roller 60 has pushed cam56 outwardly, which operates similarly'to'open exhaust valve 38 and let the car down, or-if there is leakage through the supply sideof-the main valve tending to raise the car, then this leakage is exhausted and the car brought back tolevel;
  • the arm '71 being longer than link '70 tends to quickly withdraw roller 60 from between the cams. 'When the linkage is straight-' ened out and the roller 60 projected to contact with the cams'55 or 56, there isno back thrust against the operator on the control lever.
  • this invention a new and useful improvement is made applicable to hydraulic elevators which will not only increase'their efficiency by eliminating excess motions" in stopping at a floor, but by saving excess use of p essure water, saves power in'the pumping plant; Also, this mechanism will detect leakage which is ordinarily neglected, by causing the elevator to move slightly I v back and forthwhen it is supposed to be at rest, valves 22, 38 be normally seated and yet be so blocks 57, 58 areclamped on the tapes by bolts,
  • the invention is applicable to hydraulic motors usedfor various purposes where creeping due to leakage is undesired, and to hydraulic elevators of various types and with various kinds of valves, and
  • a hydraulic elevator controlling apparatus comprising a pivoted controllever, an arm car ried'thereby, a link pivoted to said arm, a sliding member attached to said link and mounted to slide in a line'including the link attachment, and normal'to the control lever axis,:and actuating member "carried by said sliding member, hatchway means adjacent afioor operated by said actuating member when projected, and motor control means connected to be actuated by* said hatchway means.
  • hydraulic elevator controlling apparatus hydraulic motive means for moving the car, a control member movable to one position to render said motive means inoperative and to another position to render said motive means operative to move the car, a projectable actuatingmember carried by the car and connected .with said control member to be moved thereby,
  • control means adjacent aifioor engaged and Imerated by said actuating member when the latter is projected, said control member moving said actuating member to projected position when said control member is in its inoperative posi;
  • hydraulic motive means for moving the car, aoontrol'member movable to one position ,to' render said motive means inoperative and to' another position to; render said motive means operative to move the car, a projectable actuating member carried by the car and connected. with said control member to be moved thereby,
  • control member is in inoperative position to lock the actuating member in its projected position, said locking means being released by movement of said control member towards operative position.
  • V r r 4 In a hydraulic elevator controlling apparatus an operators 'pivoted control member, a projectable actuating member carried by the car connected with said control member to be actuated thereby, motor,control means adjacent a floor operated by said actuating member when i the latter is projected, the projection of said actuating member resulting in an arrangement of. the parts so that there will be no turning moment transmitted to the control member when the ac- 1 tuating member engages said motor control means:
  • an operators controller comprising a rotary member, a projectable ac- 'ltuating member slidably carried bythe car, and connecting means between said rotary member and the said actuating member, motor control an arrangement-ofthe partsso that therewill be no turning moment transmitted-to the controller means adjacent a floor operated by said actuat- 1 ing member when the latter is projected, the projection'of the said actuating member resulting in when the actuating member engages said motor control means.
  • Means for automatically holding a hydraulic I elevatorlevel at a floor against "creeping when the main valve is shut comprising auxiliary controlling means, means in the hatchway adjacent a floor level connected to said controlling means, a

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  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
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Description

Feb. 12, 1935.
ELEVATORS, ETC
J. A. ROGERS G MECHANISM FOR HYDRAULIC MOTORS,
' Filed July 8, 19:52
AUTOMATIC LEVELIN 2 Sheets-Sheet 1 INVENTOR BYW ATTORNEY ELEVATORS, ETC
2 Sheets-Sheet 2 INVENTOR ATTORNEY J. A. ROGERS Filed July 8, 1952 Feb. 12, 1935.
AUTOMATIC LEVELING MECHANISM FOR HYDRAULIC MOTORS,
Patented Feb. 12 1935 Q a A U TbMATId LE VELlN D L Q- TQ -'-1,991,000 t GTYMEGHANISM FOR i s, ,Ep vAroas-E'ro.
John A. Rogers; Rockville entre, N. -Y.,' assignor to' HydraulimElev'ator & Machine Company,
Brooklyn, N.;Y., a corporation. of New York, Application duly, 8, 1 932, Serial No. 6213504 L 7 Claims; (01. rav -2s) i This invention relates toautomaticlevelin mechanism for hydraulic motors, elevatcrs, etc and has particular reference. tomeans-whereby a hydraulic motor, andimore particularly a di-r' rect hydraulic plunger elevator can be held auto matically at a floorlevel, when the' control lever is 1at neutral position:
ion
- The invention is described herein in gc0nnec tion with the elevator mechanism shown pat- 4, 1905,1 to which reference is made, for a detailedgdescriptionof plunger elevator, main and =pilctqvalve, controlling mechanism, etc. I 1 A. system;in; general consists of a cylinder Iset vertically in the ground-tea depth, equal to the rise of the elevator, thecar being carriedby a plunger reciprocating vertically in the cylinder,"
and the car-partly counter balancedvby, icqunterg weights connected to the car by cables running over overhead sheaves, the varyingibuoyancy of the plunger being compensatedfor :by varying weight of counter-weight cables on one -or the other side of the system.. Admission oft-water under pressure to the cylinder through a supply valve lifts the car, andexhaustedwater from the cylinder throughan-exhaust valve, lowers the car. The'main supply andyexhaust valves are motoroperated and are connected to the cylinder, by. a :to-and-from pipe., Towcontrolthe ac-l tuating motor or, motors actuating the main exhaust and'supply :valve is a pilot valve; which in turn is connected-by oables to the, lever,in,the
car whichisunder the control :ofxtheoperator; Usually, there is .alinkage between the pilotvalve and the main valve, so that the pilot valve is automatically closed when the? main 2 valve is at rest in either open or closedpositiomand the degree: oi opening; of the pilot valve-to. start orstop the car correspondingly controls the, degree; of
opening .or closing of, the main valvepto starter stopithe canor control thev'speedof the' car; In an experienced-over thirty years successful operation of these elevators for high'rises-and at highspeeds, need has been fel tior some aux iliary'control ,system whereby; the car could be automatically, leveled at f the floor without; so many manipulations of the car control levenjand also" for a device to prevent uncontrolled rise for fallfof the car whenstopped at a floor. with the controllleverlin neutral'positioni'sfuch rise orfall being 1 due to leakage through the, valves. It "is impossible to maintainl the ,packings of such valves so tight as to have, ,noaleakage, and, leak age oilsupply pressure" through "the valve to the Freewares .ieaee rr ei leee e mm may'beusedalozie, it is preferable to use-both by the handof the operator. [At this position the actuating device is extended'to cooperate with stationary, Accidents havebeen known to hap- .5.
pen to operators leaving the car at a 'floor and falling down the hatchwaybecauseno t observingf that. the car had crept. away from the floor) i Sci farasI am aware, no device has heretoforebeeii proposed for successfully meeting these condi: 1c;
tions. t v H I According to-this invention, I provide an auxiliary supply and exhaust valves connectedto the to-and-irom pipe and automatically control these one or more floors where, it is desired to automatically level the car. If the car tends to drop away from the floor, it, through thefhatchway connections, will open the auxiliary supply valve andca'dmit pressure to-the to rise ,from the' floor as by, leakage. of "supply pressure into .the'cylinder, a'similardevice will i open the "auxiliary exhaust valve and let the excess pressure outof, the cylinder, While either as thereby, with proper spacing of the hatchway devices at" the "floor or floors, the. elevator can only move a.slightldistancelfrom resting position without bringing itself back v v The hatchway devices are actuated by a withdrawable connection to" the car control lever,
which itself works in conjunctionwith' a'quadrjant laste'riedto the carfh'aving accentral. notch intowhich a latch or bolt drops when, released the hatchway" devices, but at any running posi: tion, "the" latter are inoperative owing, to withdrawal oi the actuating device. a H AL particularly novel detail of [the invention resides in'a linkage means to withdraw the actuating device, which, when straightened at. the neutral position of the car lever, acts a's'a thrust elementfr'om thehatchway devices back to the car lever pivot, without b ack thrust on thelever. 5
Thus the leveling device functions whenthe car a lever is in neutral position,vwithout requiring any 7 attention by the operatorl' A further nov'el detail of theinvention'residesin the adjustments permittedflfor the hatchwayj devices to insurethe des'iredtiming, and also tomeans whereby the auxiliary or leveling supply and exhaust valves are Jself, closing or normally} closed except when one or the other is opened by the hatchway valves by means disposed in the hatchway at the 1 i cylinder,and if ittends 7 standing ropes into the car lever 11 pivoted on a car floor at 12, and carrying pulleys 13 over which the standing ropes l0 run. in usual man- 'ner.
neednot be described; and l5--is the to-and-from pipeconnected at the top of cylinder 1. 16 isthe 14 are automatic end stop valves which notch in the car quadrant receiving spring actuated bolt 1'7 on the car lever, which bolt is drawn against the spring by the hand of the operator and when he lets go, either rides on the quadrant or drops nto the notch 16 when the car lever is put into neutral position.
Describing first' the. auxiliary supply side for 1 bringing the car back 'to'the floor when it has dropped below, 20 represents a" pressure pipe ,stappe d from supply 6 and connected to valve casingf2l containing a reciprocatingported plug valve 22 (see Fig. 3). This supply pressure passesfrom valve casing 21 through pipe 23 to an auxiliary to-and-from pipe 24 connected to main to-andefrorn' pipe 15. To stem 25 of valve 22 is conneoted a link 26 which in turn is connected to lever 27 pivoted at 28. carrying a weight 29. To end of lever 27 is a flexible connection such; as
chain 30 running over 'pul1eys3'1, 32, and con-1 nected to a 'preferably flat steel tape 33 extending. up the hatchway and suspended at the top of the building by a weight running over a pulley, or a spring to counter-balance them and hold them under proper tension, it being seen that when the steel tape is lifted by means hereafter to be described, the valve 22 will be opened'to admit auxiliary supply pressure from pipes 6, 20, 23, 2 4 to the cylinder 1 to lift the plunger 2 and restore'the car to the'fioor level.
A'similar mechanism is provided for the exhaust side comprising exhaust pipe 36, exhaust valve casing 37, exhaust valve 38, exhaust pipe 39 leading to auxiliaryto-and-from'pipe 2a., Also, link 40, lever 41,weight 42, chain 43, running over pulleys, 44,145 connected to a second fiat Q steel tape46 extending up the hatchwayparallel to tape 33 and, suspended at the'top of the build ing by a weight running over a pulley, or a spring to counterfbalance'them and hold them under proper tension, are provided for actuating the auxiliary exhaust valve.
lB is a non-return check valve in supply pipe 23, and 49 is a similar valve in exhaust pipe 391 50, 51 are independently adjustable set cooks for controlling the rate offlow in'the respective supply and exhaust pipes 23, 39, to determine the speed of returning the car to level position. v
The valves 22, 38 are similarly constructed, beingexternally cylindrical and internally hollowed on a taper as shown, with sets of ports 52,v
therein, for passing the water through the valve casing when lifted. ,The'function of the internal taper is to permit an unbalanced component of the pressure to seat the valve, and in effectaid the weights 29, 42, it being essential that'these constructed as to not require too much actuating pressure to overcome the static unbalance and the weights. These cylindrical valve stems 22, 38 are packed by the usual external hat packings, with usual stuffing boxes at the top. w I
Referring to Fig. 2, at each floor in the hatchway adjacent the travel of the car, or at certain floors where automatic leveling is desired are mounted on pivots-54, one or two cams 55, .56.
These cams are mounted on aparallel linkage as shown, and when pressed outwardly of the car, or to the left in Fig. 2, lift their respective steel tape 33 or 46. This is effected by blocks 57, 58 mounted on tapes 33,46 respectively, so that when the cams 55 or 56 are pushed in, as by rollers-60 on the car, the levers 61, 62 are lifted and in engaging blocks 57, 58, liftthe respective tape 33or 46 and thereby open the corresponding auxiliary supply or exhaust valve. The
and can be adjusted up and down to fit. Springs 63, 63, return the cams 55, 56 to normal position. Set screws 64, 64 are provided for adjusting the inward positions of cams 55, 56. 1
Passing" now to 'the car mechanism, roller- 60 before mentioned, is mounted on block 67 sliding on a suitable trackwayfifi beneath the" car, and block 6'7; is-connected by red 68 to a second similarly mounted block 69. To block 69 is pivoted a link '70 which latter is pivoted to arm '71 rigidly mounted. on controller lever shaft 12. The link '70 and arm '71 constitute a linkage, when ver is in neutral position, forms a thrust mecha nism to projectthe roller 60 into the path of the cams. This is some seconds before the car actually stops, because time is required after the operator brings the car lever-to center and opens the pilot valve to close the main valve for the main valve to close, and in doing so, automatically close the pilot valve. If the car stops at the desired level, then roller" 60 comes to rest between cams 55, 56. If the car stops too soon, being below the floor, then the roller 60 through cam 55- and block 57 1lftS tape 33 and opens auxiliary supply valve 22. Likewise, if the car has once stopped at the floor andsinks because of.
roller 60 has pushed cam56 outwardly, which operates similarly'to'open exhaust valve 38 and let the car down, or-if there is leakage through the supply sideof-the main valve tending to raise the car, then this leakage is exhausted and the car brought back tolevel; I
As will be seen, the arm '71, being longer than link '70 tends to quickly withdraw roller 60 from between the cams. 'When the linkage is straight-' ened out and the roller 60 projected to contact with the cams'55 or 56, there isno back thrust against the operator on the control lever. V By, this invention a new and useful improvement is made applicable to hydraulic elevators which will not only increase'their efficiency by eliminating excess motions" in stopping at a floor, but by saving excess use of p essure water, saves power in'the pumping plant; Also, this mechanism will detect leakage which is ordinarily neglected, by causing the elevator to move slightly I v back and forthwhen it is supposed to be at rest, valves 22, 38 be normally seated and yet be so blocks 57, 58 areclamped on the tapes by bolts,
' straightened out at the time the car control le-' but inasmuch as it"prevents creeping in either preferred, it is to be understood that the invention is applicable to hydraulic motors usedfor various purposes where creeping due to leakage is undesired, and to hydraulic elevators of various types and with various kinds of valves, and
I do not restrict myself to the details shown herein except as specifically required by the appended claims. i I claim: I 1. A hydraulic elevator controlling apparatus comprising a pivoted controllever, an arm car ried'thereby, a link pivoted to said arm, a sliding member attached to said link and mounted to slide in a line'including the link attachment, and normal'to the control lever axis,:and actuating member "carried by said sliding member, hatchway means adjacent afioor operated by said actuating member when projected, and motor control means connected to be actuated by* said hatchway means.
2; In a hydraulic elevator controlling apparatus, hydraulic motive means for moving the car, a control member movable to one position to render said motive means inoperative and to another position to render said motive means operative to move the car, a projectable actuatingmember carried by the car and connected .with said control member to be moved thereby,
control means adjacent aifioor engaged and Imerated by said actuating member when the latter is projected, said control member moving said actuating member to projected position when said control member is in its inoperative posi;
tion, the projection of said actuating member re-, sulting in an arrangement of parts so that there will be no force transmitted to the control memher in a direction tending to move thesame when the actuating member engages .said control f means. a r
3. In a hydraulic elevator controlling apparatus, hydraulic motive means for moving the car, aoontrol'member movable to one position ,to' render said motive means inoperative and to' another position to; render said motive means operative to move the car, a projectable actuating member carried by the car and connected. with said control member to be moved thereby,
control member is in inoperative position to lock the actuating member in its projected position, said locking means being released by movement of said control member towards operative position. 9 V r r 4. In a hydraulic elevator controlling apparatus an operators 'pivoted control member, a projectable actuating member carried by the car connected with said control member to be actuated thereby, motor,control means adjacent a floor operated by said actuating member when i the latter is projected, the projection of said actuating member resulting in an arrangement of. the parts so that there will be no turning moment transmitted to the control member when the ac- 1 tuating member engages said motor control means:
5. In a hydraulicelevator controlling apparatus wherein there is provided an operators controller comprisinga rotary member, a projectable ac- 'ltuating member slidably carried bythe car, and connecting means between said rotary member and the said actuating member, motor control an arrangement-ofthe partsso that therewill be no turning moment transmitted-to the controller means adjacent a floor operated by said actuat- 1 ing member when the latter is projected, the projection'of the said actuating member resulting in when the actuating member engages said motor control means.
6. -In an elevator system, the combination with r a car, of hydraulic motive means for running said car including a'main valve, controlling means for saidhydraulic motive means and including an operators pivoted control element in the car which is in neutral position when the main valve is closed, automatic means'effective when said control element is in neutral position for levelling the car, said'automatic means including motor control means adjacent a floor, a projectable actuating-member connected with said control element to be projected intoa positionto engage said control means when'the control element is in neutral position, the projection of said ac I tuating memberresulting in an arrangement of v the parts so that there will be no turning mo--' 'ment transmitted to the control member when the-actuating member engages said motor control means.
7. Means for automatically holding a hydraulic I elevatorlevel at a floor against "creeping when the main valve is shut, comprising auxiliary controlling means, means in the hatchway adjacent a floor level connected to said controlling means, a
the cararrangedto be projected by said control element into a position to rengagesaid hatchway pivoted control element in the car, and means on means to actuate said hatchway means whenthe car creeps to cause said controlling means to reverse the'car, thelprojection of said projectable means resulting in an arrangement of the parts so that no turning moment will be transmitted to the control element when the projectable, means engages said hatchway means upon creeping. of
the car.
JOHN A. ROGERS.
US621504A 1932-07-08 1932-07-08 Automatic leveling mechanism for hydraulic motors, elevators, etc. Expired - Lifetime US1991000A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3892292A (en) * 1971-09-17 1975-07-01 Hitachi Ltd Hydraulic elevators

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3892292A (en) * 1971-09-17 1975-07-01 Hitachi Ltd Hydraulic elevators

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