US3661052A - Hydraulic jack - Google Patents

Hydraulic jack Download PDF

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Publication number
US3661052A
US3661052A US1789A US3661052DA US3661052A US 3661052 A US3661052 A US 3661052A US 1789 A US1789 A US 1789A US 3661052D A US3661052D A US 3661052DA US 3661052 A US3661052 A US 3661052A
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US
United States
Prior art keywords
piston
jack
operating means
rod
pressure
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
US1789A
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English (en)
Inventor
Rene Lucien
Yves A Pascal
Pierre M Ghobert
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.)
Messier SA
LAEROTRAIN SOC D
Original Assignee
Messier SA
LAEROTRAIN SOC D
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.)
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Application filed by Messier SA, LAEROTRAIN SOC D filed Critical Messier SA
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Publication of US3661052A publication Critical patent/US3661052A/en
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D65/00—Parts or details
    • F16D65/14—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position
    • F16D65/16—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position arranged in or on the brake
    • F16D65/18—Actuating mechanisms for brakes; Means for initiating operation at a predetermined position arranged in or on the brake adapted for drawing members together, e.g. for disc brakes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/12—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being liquid
    • B60T13/14—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being liquid using accumulators or reservoirs fed by pumps
    • B60T13/141—Systems with distributor valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20—Other details, e.g. assembly with regulating devices
    • F15B15/204—Control means for piston speed or actuating force without external control, e.g. control valve inside the piston
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D2121/00—Type of actuator operation force
    • F16D2121/02—Fluid pressure

Definitions

  • HYDRAULIC JACK [72] Inventors: Rene Lucien, Neuilly-sur-Seine; Yves A. Pascal, Montrouge; Pierre M. Ghobert, Paris, all of France [73] Assignees: Societe Messier; Societe De LAerotrain,
  • PATENTEDMAY 9 1912 3.6611352 SHEET U 0F 10 PATENTEDMAY 9 I972 sum as 0F 10 PATENTEUMAY 9 I972 sum 07 0F 10 PATENTEDMAY 9
  • the said hydraulic control means according to the invention preferably but not necessarily comprise a hydraulic distributor controlled in dependence on the control pressure.
  • the invention also relates to the application of a jack of this kind to the braking of vehicles, and in this case the said jack solves the problem of taking up wear of the friction linings or other actuating members of the brake in a simple and economic manner, namely by the non-existence, upon the disappearance of the control order of the inverse of the said second action,
  • the invention is more particularly but not exclusively concerned with its application to the braking of vehicles in which, for any reason whatever, the position at rest of the actuating members of the brake must be relatively distant from their working position.
  • an arrangement of this kind is necessary for vehicles on a rail of concrete or the like, the thickness of the web of the rail or rails necessitating, when taking a curve, that the brake shoes in the position of rest should be held-off so as not to intersect the envelope diagram of the said web.
  • the jack according to the invention comprises briefly, in a body forming a first point of action, a large piston, the rod of which constitutes itself a cylinder for a small piston with a long travel, forming a second point of action. At rest, the supply pressure is applied by the said servo-controlled distributor, to the said third input of the jack, from which it goes to the small piston on the side opposite to the rod, which causes its outward movement.
  • the said controlled distributor Upon the appearance of the control pressure, the said controlled distributor applies the supply pressure to the said first input ofthe jack. From the and the control pressure to the said second input of the jack and the control pressure to the said second input of the jack. From the first input, the supply pressure is applied to the rod side of the small piston, which produces its return movement, which is the said travel of large amplitude. At the end of this return movement, the small piston locks itself automatically; this locking automatically causes the application of the control pressure from the second input on the rod side of the large piston, this being the said action at high force, proportional to the control pressure.
  • TI-Ie brake and its operation described above comprise auxiliary members which will be referred to later, It will be observed that the jack according to the invention does not comprise any spring or other elastic restoring device, either for the large piston or even for the small piston, the return of which in its extended position is ensured by the supply pressure.
  • FIGS. 1 to 4 are diagrammatic figures explaining the operation of the jack according to the invention, FIG. 1 showing a condition of rest, FIG. 2 the automatic succession of the phases of the two actions, FIG. 3 the return and FIG. 4 a new condition of rest;
  • FIG. 5 gives the general diagram of the installation for an application of the invention to the actuation of the brakes of a vehicle running on a rail track with a thick center-rib or web;
  • FIG. 6 is a general axial cross-section of the jack shown in FIG. 5;
  • FIG. 7 is an explanatory detail of FIG. 6;
  • FIG. 8 shows the installation according to FIG. 5 when at rest
  • FIG. 9 shows the operation of the installation as in FIG. 5 during the first action or approach travel
  • FIGS. 10, II and 12 are three details explaining the automatic passage from the first action to the second in the installation according to FIG. 5;
  • FIG. 13 shows the operation of the installation according to FIG. 5 during the second action or application of the brakes
  • FIG. 14 shows the return to rest ofthe installation according to FIG. 5;
  • FIGS. 15, 16 and 17 are three details explaining the automatic operations during the return, as shown in FIG. 14.
  • FIGS. 1 to 4 are diagrammatic drawings explaining the operation of the jack according to the invention
  • the body 1 of the jack is provided with an eye 2 forming the first point of action and constitutes a double-acting cylinder for a large piston 3 placed between two chambers 4 and 5, and braked by a device 6 which will be described subsequently.
  • the hollow rod of the large piston 3 forms a double-acting cylinder for a small piston 7 having a long travel, placed between two chambers 8 and 9 and provided with an eye 11 forming the second point of action.
  • THe jack is supplied from a hydraulic source S through a pressure-reducing valve 23 with manual operation 25, which actuates a controlled distributor 26.
  • the said first input of the jack is the input 28, coupled to the controlled distributor 26, and the said third input of the jack which is the input 54; the said second input is the input 27, supplied by the reducing valve 23 and supplying a peripheral groove 51 of the large piston 3.
  • the pressure-reducing valve 23 connects the input 27 to the return R, and the controlled distributor 26 on the one hand connects the input 54 to the return R and on the other hand connects the input 28 to the supply pressure PA.
  • the large piston 3 is maintained in the position in which it is located by the device 6, and the small piston 7 is maintained in the extended position by the supply pressure sent into the chamber 9.
  • the pressure-reducing valve 23 regulates a control pressure PC, determined by the position of its manual control 25, and operates the control distributor 26, which on the one hand connects the input 28 to the return R, and on the other hand puts in input 54 to the supply pressure PA.
  • a control pressure PC determined by the position of its manual control 25, and operates the control distributor 26, which on the one hand connects the input 28 to the return R, and on the other hand puts in input 54 to the supply pressure PA.
  • the supply pressure PA is sent into the chamber 8, which causes the retraction of the small piston 7 (arrow F I
  • the arrival of the small piston 7 at the limit of its travel (FIG. 2, bottom left-hand) automatically causes its locking by means of a bolt 12 (which will be described subsequently).
  • FIG. 4 shows the new position of rest, which only differs from that of FIG. 1 (if wear has taken place) by a slight displacement of the moving parts, in particular of the large piston 3 which is held in position by the device 6.
  • the hydraulic supply circuit comprises a central hydraulic station (not shown), permitting the supply to the control circuit of the jack of a substantially constant hydraulic supply pressure (arrow PA).
  • This hydraulic station supplies, through the intermediary of a non-return valve 21, an oleo-pneumatic accumulator 22 which constitutes the pressure reserve of the control circuit of the jack.
  • the accumulator 22 applies a substantially-constant pressure to a hydraulic pressure-reducing valve 23, this valve delivering into the conduit system 24 a pressure which is variable (arrow PC) as a function of the control force applied to its control lever 25.
  • the pressure-reducing valve 23 permits on the one hand a hydraulic control of a servo-controlled distributor 26 and on the other hand, through the conduit 24, the controlled distributor 26 and the conduit 27, it supplies a variable pressure PC to one of the working sections ofthe doubleacting jack 1. Another working section of the jack 1 is supplied from the accumulator 22, the controlled distributor 26 and the conduit 28.
  • a further distributor 29 with manual control enables the double-acting jack to be re-set under certain conditions of use, as will be seen later.
  • the double-acting jack 1 is shown as actuating by its eyes 2 and 11, two levers 3i articulated about fixed points 32 and carrying at their extremities brakeshoes 33 which, under the working action of the jack, come into engagement with a body 34.
  • This illustration is solely employed in order to permit the explanation of the operation of the jack, it being understood that the jack according to the invention can co-operate with various other kinematic arrangements.
  • FIG. 6 which is a general axial cross-section of the jack shown in FIG. 5, the body 1 of the jack is in two parts, screwed one into the other in a fluid-tight manner, namely a bottom 41 with an eye-fork 2 and a cylinder 42 which is provided with two bores 43 and 44 in which the large piston 3 slides in a fluid-tight manner.
  • the bottom 41 is provided axially with a hollow rod 45 on which is supported the brake device 6, constituted very simply by metal rings gripping the hollow rod and housed in a hollow plug 46 screwed into the large piston 3 (on the side of the chamber).
  • the large piston 3 is provided axially with a locking piston 47, sliding in a fluid-tight manner around the hollow rod 45 and in a fluid-tight manner in the large piston 3 and the plug 46, and is urged towards the left by a compression spring 48.
  • This locking piston 47 and an internal shoulder 50 of the large piston 3 co-operate with a gripping clip 49 of the small piston 7, thus forming, as will be explained later with reference to FIGS. to 12, the locking device having the reference numeral 12 in flGS. l to 4.
  • the large piston 3 is provided with a fluid-tight peripheral groove 51 which can be put into communication with the chamber 4 by a clapper-valve 52 which will be described later with reference to FIG. 7.
  • the jack 1 is connected to four conduit systems, namely: the conduit 28 which terminates at the chamber 8; the conduit 27 which terminates at the groove 51 and at the clapper 52; a conduit 53 which comes from the distributor 29 and terminates at the chamber 5; and a conduit 54 which comes from the controlled distributor 26 and terminates at the hollow rod 45 and at the chamber 9.
  • this valve is housed in the large piston 3 and is held closed by its compression spring 56. It can be opened by mechanical thrust, as described later in connection with FIG. 12 on its end 57, and it then puts the peripheral groove 51 into communication with the chamber 4 by the conduits 58 and 59.
  • FIG. 8 which shows the installation of FIG. 5 in the condition of rest, the liquid under pressure from the accumulator 22, coming in through the intermediary of the controlled distributor 26 and the conduit 54, passes through the hollow rod 45 into the chamber 9, maintaining the small piston 7 in abutment on the left-hand side.
  • FIG. 9 shows the operation of the installation of FIG. 5 during the travel of large amplitude or approach travel
  • the control lever 25 of the pressurereducing valve 23 is actuated, a reduced pressure or control pressure appears in the conduit 24.
  • the controlled distributor 26 is actuated hydraulically and then ensures the distribution shown in FIG. 9. This distribution reconnects the conduit 54 to the tank R.
  • the conduit 27 receives the reduced pressure PC existing in the conduit 24; this pressure terminates in the groove 51 and has no action as long as the clapper-valve 52 remains against its seating.
  • the conduit 28 receives the liquid under pressure coming from the accumulator 22. The chamber 8 is thus supplied and for this reason the said piston 7 of the jack 1 is sent towards the right and the piston 3 and body 1 to the left. This achieves the approach travel; the shoes 33 have been brought up to the body 34.
  • FIGS. l0, l1 and 12 which are three details explaining, for the installation shown in FIG. 5, the automatic transition from the first action to the second:
  • the grip-clip 49 carried by the small piston 7 and constituted by a series of flexible blades, passes into the bore 50 and pushes back the locking piston 47 while compressing its spring 48.
  • the extremity of the grip-clip reaches the extremity of the bore 50, it expands and permits the extremity of the locking piston 47 to pass into the interior of the clip.
  • FIG. 13 which shows the operation of the installation shown in FIG. 5 during the second action or gripping engagement
  • the control pressure PC existing in the chamber 4 thus acts on the annular section of the large piston 3.
  • This action effects the working travel which applies the shoes 33 against the body 34.
  • the value of the pressure PC acting on the chamber 4 is more or less high, and the gripping force of the shoes 33 is more or less great.
  • FIG. 14 which shows the return to rest of the installation shown in FIG. 5, when the actuation of the control lever 25 of the pressure-reducing valve 23 ceases, the control pressure falls to zero in the conduit 24, and as the control distributor 26 is no longer actuated hydraulically, it returns to the distribution of FIG. 8 due to the action of its return spring.
  • the conduit 27 becomes connected to the tank R; there is therefore no longer any pressure existing in the chamber 4.
  • the elastic metal rings 6 which grip the hollow rod 45 maintain the large piston 3 in the position in which it was located.
  • the conduit 28 is also connected to the tank R, while the conduit 54, that is to say the chamber 9, is again connected to the accumulator 22.
  • the pressure existing in the chamber 9 acts on the locking piston 47 and causes it to return, compressing its spring 48.
  • the extremity of the locking piston 47 thus passes out of the clip 49 and frees it (FIG.
  • the small piston 7 being subjected to the pressure PA is displaced towards the left, the clip 49 is withdrawn and passes into the bore 50.
  • the clapper valve 52 is returned against its seating by the action of its restoring spring 56, which is calculated in such manner as to overcome the force of the pressure on the tail of the valve.
  • the small piston returns, carrying out the whole of its travel up to abutment.
  • the device has returned to rest.
  • the situation is identically the same as that of FIG. 8, except that the position of the large piston 3 is slightly different if wear of the shoes 33 has taken place.
  • the distributor 29 (FIG. 5) does not play any part in the operation of the device; it continuously ensures the connection of the chamber 5 to the tank R through the conduit 53.
  • the device according to the invention may advantageously find an application in the operation of a disc-brake necessitating a very large liberating travel of the brakeshoes, at the same time providing an acceptable response time.
  • the presence ofthe pressure-reducing valve 23 enables the braking pressure to be varied at will while actuating the jack 1 by a single control.
  • this jack by reason of the relative action of the clip 49 and the clapper-valve 52, comprises a device with an incorporated sequence, first ensuring the approach travel and then immediately and automatically effecting the working travel.
  • a hydraulic jack having two consecutive and complete different actions and a hydraulic operating means for fumishing a supply pressure under the action of a control pressure, said jack comprising a body, said body forming a first point of action and constituting a first cylinder, a first piston in said first cylinder and a first rod fast with said first piston and directed towards the side opposite to said first point of action,
  • said first piston defining in said first cylinder a chamber on the rod side and a chamber on the side opposite to said rod, said first piston being provided with a peripheral groove, a clappervalve between said groove and said rod-side chamber, said first rod forming a second cylinder, a second piston in said second cylinder, a second rod fast with said second piston and directed towards the side opposite to said first piston and forming a second point of action, said second piston defining in said second cylinder a chamber on the rod side and a chamber on the side opposite to said rod, and said hydraulic operating means responding to the control pressure when said pressure exceeds a selected threshold, by sending the supply pressure into said rod side chamber of said second piston on the one hand, and the control pressure into said peripheral groove of the said first piston on the other hand, and when said control pressure does not reach said threshold value, by sending the supply pressure into the chamber of said second piston on the opposite side to its rod.
  • Ajack and its operating means as claimed in claim 1 comprising locking means including an elastic grip-clip fast with said second piston and adapted to engage in a shoulder of said first piston, and a locking piston with a compression spring adapted to slide in said first piston and to lock said clip in said position.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Transportation (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Braking Arrangements (AREA)
US1789A 1969-01-10 1970-01-09 Hydraulic jack Expired - Lifetime US3661052A (en)

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FR6900313A FR2029119A5 (fr) 1969-01-10 1969-01-10

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5584701A (en) * 1992-05-13 1996-12-17 University Of Florida Research Foundation, Incorporated Self regulating lung for simulated medical procedures
US5772442A (en) * 1992-05-13 1998-06-30 University Of Florida Research Foundation, Inc. Apparatus and method for simulating bronchial resistance or dilation
US6273728B1 (en) 1997-09-04 2001-08-14 The University Of Florida Life support simulation system simulating human physiological parameters
US6474215B1 (en) 1998-07-08 2002-11-05 Aro Actuator with approach pre-stroke and working stroke for operating a tool
US9914467B2 (en) 2015-08-14 2018-03-13 Oldcastle Light Building Products, LLC Attachment and support members for modular building structures
US10344487B2 (en) 2015-08-14 2019-07-09 Oldcastle Light Building Products, LLC Attachment and support members for modular building structures

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2834339B1 (fr) * 2001-12-31 2004-02-27 Bosch Gmbh Robert Verin pneumatique pour le test d'un servomoteur

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3306031A (en) * 1963-07-03 1967-02-28 Participations Soc Et Valve control devices, in particular for gas turbine power plants
US3483798A (en) * 1967-03-30 1969-12-16 Koehring Co Telescopic hydraulic actuator

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3306031A (en) * 1963-07-03 1967-02-28 Participations Soc Et Valve control devices, in particular for gas turbine power plants
US3483798A (en) * 1967-03-30 1969-12-16 Koehring Co Telescopic hydraulic actuator

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5584701A (en) * 1992-05-13 1996-12-17 University Of Florida Research Foundation, Incorporated Self regulating lung for simulated medical procedures
US5769641A (en) * 1992-05-13 1998-06-23 University Of Florida Research Foundation, Inc. Apparatus and method for synchronizing cardiac rhythm related events
US5772443A (en) * 1992-05-13 1998-06-30 University Of Florida Research Foundation, Inc. Apparatus and method for detecting and identifying a drug
US5772442A (en) * 1992-05-13 1998-06-30 University Of Florida Research Foundation, Inc. Apparatus and method for simulating bronchial resistance or dilation
US5779484A (en) * 1992-05-13 1998-07-14 University Of Florida Research Foundation Apparatus and method of stimulating breathing sounds
US5868579A (en) * 1992-05-13 1999-02-09 University Of Florida Research Foundation, Inc. Apparatus and method for simulating lung sounds in a patient simulator
US5882207A (en) * 1992-05-13 1999-03-16 University Of Florida Research Foundation Apparatus and method for quantifying fluid delivered to a patient simulator
US5890908A (en) * 1992-05-13 1999-04-06 University Of Florida Research Foundation Apparatus for and method of simulating the injection and volatilizing of a volatile drug
US5941710A (en) * 1992-05-13 1999-08-24 University Of Florida Research Foundation Apparatus and method of simulating the determination of continuous blood gases in a patient simulator
US6273728B1 (en) 1997-09-04 2001-08-14 The University Of Florida Life support simulation system simulating human physiological parameters
US6474215B1 (en) 1998-07-08 2002-11-05 Aro Actuator with approach pre-stroke and working stroke for operating a tool
AU758224B2 (en) * 1998-07-08 2003-03-20 Aro Actuator with approach pre-stroke and working stroke for operating a tool
US9914467B2 (en) 2015-08-14 2018-03-13 Oldcastle Light Building Products, LLC Attachment and support members for modular building structures
US10344487B2 (en) 2015-08-14 2019-07-09 Oldcastle Light Building Products, LLC Attachment and support members for modular building structures

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Publication number Publication date
CA920070A (en) 1973-01-30
FR2029119A5 (fr) 1970-10-16

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