US3884124A - Hydraulic device - Google Patents

Hydraulic device Download PDF

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Publication number
US3884124A
US3884124A US352424A US35242473A US3884124A US 3884124 A US3884124 A US 3884124A US 352424 A US352424 A US 352424A US 35242473 A US35242473 A US 35242473A US 3884124 A US3884124 A US 3884124A
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US
United States
Prior art keywords
slipper
chambers
rotor
hydraulic device
stator
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US352424A
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English (en)
Inventor
Robert T Eddy
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Reliance Electric Co
Original Assignee
Reliance Electric Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Reliance Electric Co filed Critical Reliance Electric Co
Priority to US352424A priority Critical patent/US3884124A/en
Priority to CA191,519A priority patent/CA1008301A/en
Priority to GB519774A priority patent/GB1424993A/en
Priority to AU65304/74A priority patent/AU477618B2/en
Priority to DE2409119A priority patent/DE2409119A1/de
Priority to BE141617A priority patent/BE811840A/xx
Priority to FR7410483A priority patent/FR2226570B1/fr
Priority to JP49039547A priority patent/JPS50249A/ja
Priority to IT21599/74A priority patent/IT1009911B/it
Application granted granted Critical
Publication of US3884124A publication Critical patent/US3884124A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03C—POSITIVE-DISPLACEMENT ENGINES DRIVEN BY LIQUIDS
    • F03C1/00—Reciprocating-piston liquid engines
    • F03C1/02—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders
    • F03C1/04—Reciprocating-piston liquid engines with multiple-cylinders, characterised by the number or arrangement of cylinders with cylinders in star or fan arrangement
    • F03C1/0403—Details, component parts specially adapted of such engines
    • F03C1/0435—Particularities relating to the distribution members
    • F03C1/0444—Particularities relating to the distribution members to plate-like distribution members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B1/00—Reciprocating-piston machines or engines characterised by number or relative disposition of cylinders or by being built-up from separate cylinder-crankcase elements
    • F01B1/06—Reciprocating-piston machines or engines characterised by number or relative disposition of cylinders or by being built-up from separate cylinder-crankcase elements with cylinders in star or fan arrangement
    • F01B1/0641—Details, component parts specially adapted for such machines
    • F01B1/0644—Pistons
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01B—MACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B13/00—Reciprocating-piston machines or engines with rotating cylinders in order to obtain the reciprocating-piston motion
    • F01B13/04—Reciprocating-piston machines or engines with rotating cylinders in order to obtain the reciprocating-piston motion with more than one cylinder
    • F01B13/06—Reciprocating-piston machines or engines with rotating cylinders in order to obtain the reciprocating-piston motion with more than one cylinder in star arrangement
    • F01B13/061—Reciprocating-piston machines or engines with rotating cylinders in order to obtain the reciprocating-piston motion with more than one cylinder in star arrangement the connection of the pistons with the actuated or actuating element being at the outer ends of the cylinders

Definitions

  • a hydraulic motor having a stator with alternately inwardly and outwardly, radially extending reaction surfaces, a rotor disposed within said stator and having a plurality of chambers in its peripheral surface elongated in the direction of the axis of the rotor, and slippers disposed in each of the chambers for reciprocating movement therein.
  • Each slipper has a recess in the surface facing the reaction surfaces, and a rolling element disposed in each recess contacts the reaction surface.
  • Relative movement between the stator and rotor causes a tilting action of the slipper which is utilized to form a Contact seal between the side of theslipper and the side walls of the chambers.
  • Lubricating channels may be provided in the surface of the recess to lubricate the rolling element, utilizing the hydraulic fluid communicated to the channels by passages in the slipper. While the hydraulic device is intended primarily for use as a motor, the principles involved in the motor may be utilized effectively in a pump.
  • Another object of the invention is to provide a motor having a plurality of reaction elements, which will not become pumping elements in the event the equipment, normally driven by the motor, drives the motor, and which hence will not cause cavitation in the hydraulic lines of the system, but rather becomes free wheeling whenever the foregoing condition develops in the motor-equipment installation, thus minimizing the braking action of the motor during such operating conditions.
  • Still another object is to provide a relatively simple, compact and versatile hydraulic motor having a series of reciprocating elements forming a pressure responsive means in individual chambers, which have a slipper-type wear compensating and fluid sealing structure, for increasing the operating efficiency and extending the effective life of the elements, and which is easily serviced and repaired to maintain the motor in optimum operating condition.
  • a further object is to provide a motor of the aforementioned type having a stator and a rotor in which the rotor and the output shaft therefor are hydraulically balanced.
  • FIG. 1 is an elevational view of the present hydraulic motor
  • FIG. 2 is an enlarged crosssectional view of the hydraulic motor shown in FIG. 1, the section being taken on line 2 2 of the latter figure;
  • FIG. 3 is a transverse cross-sectional view of the hy draulic motor shown in the preceding figures, the section being taken on line 3 3 of FIG. 2;
  • FIG. 4 is a cross-sectional view of the hydraulic motor, the section being taken on line 4 4 of FIG. 2;
  • FIG. 5 is a fragmentary cross-sectional view of the rotor, the section being taken on line 5 5 of FIG. 4;
  • FIG. 6 is an enlarged diagrammatical view of one of the cylinders of the motor, illustrating the operation of the piston and slipper type seal incorporated therein;
  • FIG. 7 is an enlarged detail view of a slightly modified form of the slipper used in the device shown in the preceding figures.
  • FIG. 8 is a side elevational view of the slipper shown in FIG. 7.
  • numeral 10 indicates generally the present hydraulic motor having fluid inlet passage 12, fluid outlet passage 14, and power output shaft 16. While the description is directed to the present device as a hydraulic motor, it may be used as a hydraulic pump if desired with few or no changes in the basic structure thereof; however, the description hereinwill be directed primarily to the use of the device as a hydraulic motor.
  • the system in which the motor is used normally includes a hydraulic pump for providing the necessary hydraulic pressure through a line from the pump to inlet 12 and a return line connected to outlet 14.
  • the system including the motor and the pump which is normally driven by an electrical motor or an engine, may be used to drive a variety of different types of machines or equipment, connected to shaft 16 of the hydraulic motor.
  • the motor 10 consists of a rotor 20 having a plurality of fluid chambers 22 and rolling elements 24 in the fluid chambers operating in effect as pistons.
  • the rotor is mounted on output shaft 16 and secured thereto by key 26 disposed in key-ways 28 and 30 in the rotor and shaft, respectively.
  • the rotor is disposed in a stationary stator 40 or reaction member, the external part of which forms the periphery of housing 42 which includes end sections 44 and 46 and intermediate section or port ring 48.
  • the four sections 40, 44, 46 and 48 are secured together to form a rigid housing structure by a plurality of bolts 50 extending through holes in the sections and being threadedly received in holes 52 in section 44, and the sections are preferably sealed by gaskets such as O-rings 49.
  • Shaft 16 is journaled in bearings 54 and 56 disposed in annular recesses in the internal face of sections 44 and 46, the shaft being sealed by an annular seal 58 in the enlarged opening 60 through the end section 44 in which the shaft rotates.
  • the shaft is held against end-wise axial movement by a collar 62 engaging bearing 54 and shoulder 64 engaging bearing 56, and the outer end of shaft 16 is provided with a key and key-way in order to connect the shaft to the driven mechanism or equipment.
  • a sheave, gear, or other drive transmission element may be mounted on the shaft, or the shaft may be coupled directly to the input shaft of the driven equipment.
  • the chambers 22 in rotor 20 consist of slots extendlng across the periphery of the rotor, and the rolling elements 24 are adapted to reciprocate therein from the internal end of the chamber, as viewed in the one at the top of FIG. 4, to their fully extended position as illustrated by the two cylinders in approximately the 4 and 8 oclock positions as viewed in FIG. 4.
  • the rolling elements are forced outwardly by the pressure in the chambers on the internal side of the elements 24 and the elements react against the increasing surfaces of each lobe 72 on the cam surface of reaction member 40.
  • the fluid is ejected therefrom through outlet 14 at a relatlvely low pressure, as the rolling elements 24 engage decreasing cam surfaces 74.
  • the number of lobes 72 on the cam surface is different from the number of chambers and rolling elements, either greater or fewer in number, in order to maintain a uniform operation in the device.
  • the rolling elements 24 are cylindrical in shape and are substantially the same length as the width of rotor and form a relatively snug fit at the ends between sections 44 and 48, as seen in FIG. 2, thus eliminating or minimizing the flow of fluid from the inner end of chambers 22 to the space 80 between lobes 72, although some fluid may seep into the spaces 80, and a drain is provided therefor.
  • the spaces are connected to one another by an annular passage 81 in the inner face of section 44.
  • the fluid finding its way into space 80 is removed by a drain passage 82 extending inwardly to a transverse passage 84 adjacent shaft 16.
  • This transverse passage communicates with a drain cavity 86 which is in turn drained by a conduit (not shown) connected to cavity 86 through threaded hole 88.
  • a conduit not shown
  • Chambers 22 are alternately connected to the high pressure inlet 12 and low pressure outlet 14 by ports 90 and 92 in port plate or section 48, the ports 90 being connected by an annular groove 96 in section 46 with inlet port 12, and ports 92 being connected by annular groove 94 in section 46 with outlet port 14.
  • the rolling elements 24 are traversing outwardly extending inclines 70 of the cam surface on the stator, and when the chambers are in communication with ports 92, the rolling elements are traversing inwardly extending surfaces 74. The rolling elements are urged outwardly by the high pressure transmitted to the chamber from conduit 12 and ports 90, against the inclined surfaces 70, thus 1 causing rotational movement of rotor 20.
  • the inwardly inclined portions 74 return the rolling elements to the inner ends of chambers 22, causing the fluid in the chambers to be ejected through ports 92 and low pressure outlet 14.
  • the rotor is hydraulically balanced by the transmittal of hydraulic fluid to the side of the rotor 20 opposite ports 90 and 92. These ports are connected by a passage 100 extending completely through the rotor to slots 102 which are shown as located in the surface of section 44, but which may be located in the respective side of the rotor. Passage 100 transmits the pressure of either ports 90 or ports 92 to the opposite side of the rotor, and since slots 102 communicate with passage 100, the pressure of the fluid received from passage 100 is applied to the left hand side of the rotor as viewed in FIG. 2, i.e.
  • each of the slots 102 contains fluid under a pressure representing the pressure being applied at the particular moment on the opposite side of the rotor.
  • Rolling elements 24 are mounted in slippers 110 which in turn are mounted in chambers 22.
  • the primary advantage of the combination rolling element and slipper is the ability of the slipper to maintain an effective seal between the side walls in the rotor defining chambers 22.
  • the slipper is so constructed that an effective sealing contact is maintained by the pressure applied on the rolling elements as the rolling elements reciprocate inwardly and outwardly in engagement with the undulating cam surface.
  • the slipper tends to rotate angularly in the counter clockwise direction, as viewed in FIG. 4, thus applying additional pressure at points or edges 112 and 114 on the side walls of chamber 22. As seen in FIG.
  • lubricating grooves are provided so that the hydraulic fluid can effectively lubricate the cylindrical piston disposed in bearing recess 120.
  • the system for lubricating the roller includes two longitudinal grooves 122 and 124 spaced laterally from the center of bearing recess 120, and grooves 126 and 128 in opposite ends of the slipper communicating with the ends of grooves 122 and 124, respectively. Hydraulic fluid is thus permitted to flow from chamber 22 through grooves 126 and 128 at each end of slipper into grooves 122 and 124 where it effectively forms a film on the inner surface of recess between the slipper walls and the rotating cylindrical element 24.
  • a plurality of grooves 130 are provided on the sides of the slipper. While these grooves 130 assist in maintaining effective lubrication between the slipper walls of the chamber, they also assist in minimizing leakage which might tend to occur between the walls of the two slippers and cylinders as the slippers tilt or shift from one sealing position to another.
  • the fluid is transmitted from a high pressure source to inlet 12.
  • the high pressure fluid then passes through annular groove 96 and ports 90 into the chambers which are in communication with ports 90.
  • These chambers contain the rolling elements in contact with the outwardly extending inclined portions 70 of the cam surface of the stator.
  • the high pressure forcing the rolling elements outwardly causes the rotor to rotate in the clockwise direction, as viewed in FIG. 4.
  • the chambers containing the rolling elements in contact with the inwardly extending inclined surfaces 74 are in communication with the ports 92, which in turn are in communication with groove 94 and outlet port 14.
  • a hydraulic device comprising a stator means, a rotor means, one of said means having a plurality of alternate outwardly and inwardly, radially extending reaction surfaces and the other of said means having a plurality of fluid chambers with an opening facing said reaction surfaces, a slipper disposed in each of said chambers for reciprocating movement therein and having a recess in the surface facing said reaction surfaces, a rolling element disposed in said recess and contacting said reaction surfaces, each of said slippers being tiltable to both sides of the radial center line of the respective roller by the motion between the stator and rotor means to form a contact seal with both side walls of its chamber, the side walls of said slippers having a curvature which increases the sealing contact pressure as the slipper tips further from the radial center line of the respective chamber, and fluid inlet and outlet ports bein alternately connected with said chambers.
  • stator means is annular shaped and contains the outwardly and inwardly extending reaction surfaces
  • said rotor means is disposed within said stator means, and said fluid chambers are disposed in said rotor means in the periphery thereof.
  • a hydraulic device as defined in claim 1 in which said chambers are elongated in the axial direction of said rotor means and extend to the opposite edges of said means.
  • a hydraulic device as defined in claim 2 in which said chambers are elongated in the axial direction of said rotor means and extend to the opposite edges of said means.
  • a hydraulic device as defined in claim 3 in which said slippers are substantially the same length as said chambers and said rolling elements are cylindrically shaped and substantially the same length as said chambers.
  • a slipper element for said chambers having an elongated body of substantially the same axial length as the cylinders and elongated recess extending in the axial direction disposed in the surface of said element and facing said reaction surfaces for receiving a rolling element, said slipper element being tiltable to both sides of the radial center line of the respective roller by the relative motion between said stator and rotor means to form a contact seal with both side walls of the chamber, the side walls of said slippers having a curvature which increases the sealing contact pressure as the slipper tips further from the radial center line of the respective chamber.
  • a slipper element as defined in claim 7 in which longitudinal grooves are provided in the side wall of said recess and a passage connects each of said grooves with the respective fluid chamber for lubricating the rolling element.
  • a slipper element as defined in claim 7 in which a longitudinal groove is disposed on opposite sides of the external surface of said slipper.
  • a hydraulic device as defined in claim 7 in which the chambers are in the rotor means, and said slipper element applies a fluid sealing force to the walls of said rotor means defining the respective chamber as the rolling element supported by said slipper element engages said alternately outward and inward reaction surfaces.
  • a hydraulic device as defined in claim 10 in which the walls defining said chamber in said rotor means extend axially from one side of the rotor means to the other and are straight and parallel to one another in the area engaged by said slipper element.
  • a hydraulic device as defined in claim 11 in which opposite sides of said slipper element firmly contact opposite walls of the respective chamber when said slipper elements are tilted by the relative movement of the rotor means in the stator means.
  • a hydraulic device as defined in claim 12 in which opposite sides of said slipper element contact opposite walls of the respective chamber when said slipper elements are tilted by the relative movement of the rotor means in the stator means, with the margins of the longitudinal side edges of the slipper element forming the line of contact between the slipper element and the sides of the respective chambers.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Hydraulic Motors (AREA)
  • Rotary Pumps (AREA)
  • Reciprocating Pumps (AREA)
US352424A 1973-04-19 1973-04-19 Hydraulic device Expired - Lifetime US3884124A (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
US352424A US3884124A (en) 1973-04-19 1973-04-19 Hydraulic device
CA191,519A CA1008301A (en) 1973-04-19 1974-02-01 Hydraulic motor
GB519774A GB1424993A (en) 1973-04-19 1974-02-05 Hydraulic pump or motor
AU65304/74A AU477618B2 (en) 1973-04-19 1974-02-07 Hydraulic device
DE2409119A DE2409119A1 (de) 1973-04-19 1974-02-26 Hydraulische vorrichtung
BE141617A BE811840A (fr) 1973-04-19 1974-03-04 Dispositif hydraulique
FR7410483A FR2226570B1 (enrdf_load_stackoverflow) 1973-04-19 1974-03-27
JP49039547A JPS50249A (enrdf_load_stackoverflow) 1973-04-19 1974-04-09
IT21599/74A IT1009911B (it) 1973-04-19 1974-04-18 Dispositivo idraulico

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US352424A US3884124A (en) 1973-04-19 1973-04-19 Hydraulic device

Publications (1)

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US3884124A true US3884124A (en) 1975-05-20

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Application Number Title Priority Date Filing Date
US352424A Expired - Lifetime US3884124A (en) 1973-04-19 1973-04-19 Hydraulic device

Country Status (8)

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US (1) US3884124A (enrdf_load_stackoverflow)
JP (1) JPS50249A (enrdf_load_stackoverflow)
BE (1) BE811840A (enrdf_load_stackoverflow)
CA (1) CA1008301A (enrdf_load_stackoverflow)
DE (1) DE2409119A1 (enrdf_load_stackoverflow)
FR (1) FR2226570B1 (enrdf_load_stackoverflow)
GB (1) GB1424993A (enrdf_load_stackoverflow)
IT (1) IT1009911B (enrdf_load_stackoverflow)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4144798A (en) * 1976-07-15 1979-03-20 Cyphelly Ivan J Fluid pressure unit with hydrostatic torque transmission by roller pistons
US11399460B1 (en) * 2018-06-13 2022-08-02 Parker-Hannifin Corporation Blade rotation system
CN115875186A (zh) * 2023-02-27 2023-03-31 太原科技大学 一种集成共转子结构高扭矩密度内曲线液压马达

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5313924Y2 (enrdf_load_stackoverflow) * 1974-08-21 1978-04-14
CH642147A5 (de) * 1979-05-18 1984-03-30 Glyco Antriebstechnik Gmbh Verdraengermaschine mit hydrostatischer drehmomentuebertragung mittels rollenkolben.
GB8506070D0 (en) * 1985-03-08 1985-04-11 Rieter Scragg Ltd Applying liquids to yarns
DE102008017823B4 (de) * 2008-04-08 2016-09-29 Continental Automotive Gmbh Hochdruckpumpe mit einem Pumpenkolben, einem Stößel und einem Rollenschuh bestehend aus wenigstens zwei plattenförmigen Rollenschuhsegmenten

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1495526A (en) * 1923-08-13 1924-05-27 Phillips Harry Clarence Rotary prime mover, motor, compressor, pump, and the like
US1567912A (en) * 1923-01-16 1925-12-29 Carey Robert Falkland Hydraulic clutch
US2292181A (en) * 1940-05-20 1942-08-04 Hydraulic Dev Corp Inc Hydraulic pump or motor
US2459786A (en) * 1945-03-12 1949-01-25 Beaman Bernard Hydraulic pressure pump or motor
US2612110A (en) * 1947-01-11 1952-09-30 Carl J Delegard Pump and motor
US2712794A (en) * 1949-06-15 1955-07-12 Marion W Humphreys Fluid motor or pump
US3046950A (en) * 1958-01-22 1962-07-31 Whiting Corp Constant mechanical advantage rotary hydraulic device
US3699848A (en) * 1968-05-23 1972-10-24 Cam Rotors Ltd Radial piston fluid pressure motor
US3724334A (en) * 1969-07-22 1973-04-03 Nutron Corp Mechanical driving

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1567912A (en) * 1923-01-16 1925-12-29 Carey Robert Falkland Hydraulic clutch
US1495526A (en) * 1923-08-13 1924-05-27 Phillips Harry Clarence Rotary prime mover, motor, compressor, pump, and the like
US2292181A (en) * 1940-05-20 1942-08-04 Hydraulic Dev Corp Inc Hydraulic pump or motor
US2459786A (en) * 1945-03-12 1949-01-25 Beaman Bernard Hydraulic pressure pump or motor
US2612110A (en) * 1947-01-11 1952-09-30 Carl J Delegard Pump and motor
US2712794A (en) * 1949-06-15 1955-07-12 Marion W Humphreys Fluid motor or pump
US3046950A (en) * 1958-01-22 1962-07-31 Whiting Corp Constant mechanical advantage rotary hydraulic device
US3699848A (en) * 1968-05-23 1972-10-24 Cam Rotors Ltd Radial piston fluid pressure motor
US3724334A (en) * 1969-07-22 1973-04-03 Nutron Corp Mechanical driving

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4144798A (en) * 1976-07-15 1979-03-20 Cyphelly Ivan J Fluid pressure unit with hydrostatic torque transmission by roller pistons
US11399460B1 (en) * 2018-06-13 2022-08-02 Parker-Hannifin Corporation Blade rotation system
CN115875186A (zh) * 2023-02-27 2023-03-31 太原科技大学 一种集成共转子结构高扭矩密度内曲线液压马达
CN115875186B (zh) * 2023-02-27 2023-04-28 太原科技大学 一种集成共转子结构高扭矩密度内曲线液压马达

Also Published As

Publication number Publication date
CA1008301A (en) 1977-04-12
IT1009911B (it) 1976-12-20
JPS50249A (enrdf_load_stackoverflow) 1975-01-06
AU6530474A (en) 1975-08-07
DE2409119A1 (de) 1974-11-14
FR2226570A1 (enrdf_load_stackoverflow) 1974-11-15
FR2226570B1 (enrdf_load_stackoverflow) 1978-06-02
BE811840A (fr) 1974-07-01
GB1424993A (en) 1976-02-11

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