US3773084A - Control for mobile construction machine - Google Patents

Control for mobile construction machine Download PDF

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Publication number
US3773084A
US3773084A US3773084DA US3773084A US 3773084 A US3773084 A US 3773084A US 3773084D A US3773084D A US 3773084DA US 3773084 A US3773084 A US 3773084A
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United States
Prior art keywords
plunger
bore
valve
signal
handball
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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
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English (en)
Inventor
G Bernhoft
D Miller
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.)
Bank of New England NA
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Koehring Co
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Publication of US3773084A publication Critical patent/US3773084A/en
Assigned to KOEHRING COMPANY, A CORP. OF DE reassignment KOEHRING COMPANY, A CORP. OF DE ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: KOEHRING COMPANY A WI CORP.
Assigned to BANK OF NEW ENGLAND NATIONAL ASSOCIATION reassignment BANK OF NEW ENGLAND NATIONAL ASSOCIATION ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: KOEHRING CRANES & EXCAVATORS, INC.
Assigned to KOEHRING CRANES & EXCAVATORS, INC., A CORP. OF DE reassignment KOEHRING CRANES & EXCAVATORS, INC., A CORP. OF DE RELEASED BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: BANK OF NEW ENGLAND NATIONAL ASSOCIATION
Anticipated expiration legal-status Critical
Assigned to IBJ SCHRODER BANK & TRUST COMPANY reassignment IBJ SCHRODER BANK & TRUST COMPANY SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: TEREX CORPORATION
Assigned to TEREX CORPORATION reassignment TEREX CORPORATION RELEASE OF SECURITY INTEREST AND REASSIGNMENT Assignors: IBJ SCHRODER BANK & TRUST COMPANY, AS AGENT
Expired - Lifetime legal-status Critical Current

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Classifications

    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/2004—Control mechanisms, e.g. control levers
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/86919—Sequentially closing and opening alternately seating flow controllers

Definitions

  • ABSTRACT A control for a mobile excavating backhoe comprising a handball including a trigger lever mounted for pivotal movement, a plunger operatively associated therewith, internal passages for permitting pressurized air to flow between inlet, exhaust and signal ports, and a metering or modulating valve regulating the air flow between the inlet, exhaust and signal ports. Pivotal movement of the lever is translated into axial movement of the plunger and the metering valve to produce a variable pressure signal at one of the signal ports in the handball.
  • the signal controls an air cylinder in the pneumatic control system, and the cylinder is connected to a hydraulic control valve which provides the necessary oil pressure for operating a double acting hydraulic cylinder secured to the frame of an earthmoving machine.
  • the magnitude of the variable pressure signal determines the extent of movement of the hydraulic control valve, thus providing proportional control over thefunctions of the earth-moving machine.
  • the invention relates to improvements in controls for construction and earthmoving machines, and more specifically, to metering controls for mobile excavators such as backhoes and the like.
  • the instant invention contemplates a unique handball to be mounted on construction machinery control levers and including a selectively variable control valve characterized by a trigger lever mounted for pivotal movement atop the handball, a plunger disposed in abutting relationship to the trigger lever, internal passages for permitting pressurized air to flow between inlet, exhaust and signal ports, and a metering or modulating valve for regulating the flow of fluid between the inlet, exhaust and signal ports in response to movement of the trigger lever.
  • the pivotal movement of the trigger lever is translated into axial movement of the plunger which shifts the metering or modulating valve so that an air signal whose magnitude is proportionaito the extent of trigger lever movement is generated.
  • the variable air signal is supplied to a pneumatic control system including inter alia, an actuating air cylinder which adjusts the position of the double acting hydraulic control valve.
  • the hydraulic control valve actuates a hydraulic cylinder which controls related functions of an earth-moving machine.
  • the extent of movement of the hydraulic control valve is directly related through the actuating air cylinder to the magnitude of the variable pressure air signal.
  • the unique handball design affords precise regulation of the speed of performance of the machine functions and substantially reduces the cooling effect experienced with known handballs since less volume of air passes, at a lower pressure, through the new handball device.
  • the compactness of the trigger lever and modulating valve of the instant invention permit a pair of trigger levers and a like pair of modulating valves to be operatively associated with a single handball; consequently the machine operator can exercise proportional control over related machine functions with one hand.
  • the handball may be equipped with long air lines and be removable from the operators cab for remote control of dig and bucket functions to allow the operator to stand outside the cab of the machine and peer down into a deep trench.
  • FIG. 1 is a vertical cross-sectional view through a removable handball constructed in accordance with the principles of the instant invention
  • FIG. 2 is a bottom plan view of the handball, such view being taken along line 2-2 in FIG. 1 and in the direction indicated;
  • FIG. 3 is a view of a detail of the handball of FIG. 1;
  • FIG. 4 is a cross-sectional view of the handball, such view being taken along line 4-4 in FIG. I and in the direction indicated;
  • FIG. 5 is a cross-sectional view of the handball, such view being taken along line 55 in FIG. 1 and in the direction indicated;
  • FIG. 6 is a front elevational view of the handball of FIG. 1;
  • FIG. 7 is a schematic representation of the pneumatic and hydraulic circuits controlled by the handball of FIG. I.
  • FIG. 8 is a perspective view of the handball of the instant invention shown in combination with control levers of a mobile construction machine.
  • FIG. 1 depicts a handball indicated generally by reference character 10 and constructed in accordance with the principles of the instant invention.
  • a threaded opening 12 is formed in the lower surface of the handball, and a control lever 14 is screw threaded into the opening to secure the handball in fixed, yet removable, position atop the lever.
  • a first bore 16 and a second bore 18 extend axially throughout the body of the handball. Since the components located with bores 16 and 18 are identical, only those components located within bore 16 will be described in detail at this juncture.
  • Trigger lever 20 is retained in position at the upper end of bore 16 by a pin 22.
  • a cylindrical plunger 24 is situated adjacent to the lower end of the trigger lever, and a washer 26 is retained in position near the lower end of the plunger by snap ring 28.
  • a lubricating seal 25 is positioned in a recess in the handball body, and plunger 24 passes therethrough.
  • the washer provides a seat for upper control spring 30 which encircles the reduced-diameter section of plunger 24 and biases the plunger unpwardly.
  • plunger 24 extends into an upwardly opening cavity 32 at the upper end of spacer 34, and washer 26 engages the annular wall of the spacer defining cavity 32.
  • a pin 36 with a threaded upper end is screwed into engagement with a central bore 38 in spacer 34.
  • the lower end of pin 36 terminates in a needle-like segment 37.
  • a sealing washer 40 is snugly held on the upper portion of pin 36 in engagement with the lower face of spacer 34.
  • a plug 42 is secured to handball at the lower end of bore 16.
  • the innermost end of plug 42 defines an annular seat 44 which cooperates with the lower face of washer 40.
  • An axial passageway 46 extends through the plug and serves as an inlet port, and pin 36 is movable within the passageway.
  • O-rings 48 and 50 are seated in annular recesses in the walls of plug 42 for sealing purposes.
  • An annular passageway 52 communicates with passageway 46 via radial passageway 54, and passageway 54 is in communication with first signal port 55, indicated by dotted lines in FIG. 1. The signal at port 55 is transmitted via conduit 57 to the pneumatic control circuit.
  • Needle-like segment 37 of pin 36 passes through a constricted portion of passageway 46 and contacts ball 56, which is urged by lower control spring 58 upwardly against the shoulder defined by the constriction in passage 46. Threaded nut 59 is screwed into sealing engagement with plug 42 and prevents axial communication therethrough.
  • trigger lever 120 is retained at the upper end of bore 18 by a pin 122 and a cylindrical plunger 124 is situated adjacent to the lower end of the trigger lever.
  • Bore 18 further houses dirt seal 125, washer 126, snap ring 128, and upper control spring 130 which encircles the reduced diameter section of plunger 124 and biases the plunger upwardly.
  • plunger 124 extends into cavity 132 at the upper end of spacer 134, and washer 126 engages the annular walls defining the cavity.
  • Pin 136 which terminates in segment 137, is screwed into engagement with central bore 138 in spacer 13 A sealing washer 140 engages the lower face of the spacer.
  • Plug 142 seals the lower end of bore 18, and the innermost end of the plug defines an annular seat 144.
  • Axial passageway 166 extends through the plug, and O-rings 148 and 150 perform a sealing function.
  • An annular passageway 152 communicates with passageway 146 via radial passageway 154, and passageway 154 is in communication with second signal port 155, which is not visible in FIG. 1 but is clearly indicated in FIGS. 2 and 4. Segment 137 of pin 136 passes through a constricted portion of passageway 146 and contacts ball 156, which is biased upwardly by lower control spring 158.
  • a conduit 60 is slipped over nipple 62, to supply air to both bores situated within the interior of the handball.
  • Bore 18 is pressurized directly from the axial passage through nipple 62, while bore 16 is pressurized indirectly via radial passageway 70.
  • Passageway 64 communicates with both bores 16 and 18 and opens into exhaust port 66 located adjacent to the upper end of opening 12.
  • Conduit 68 is secured in place at the outer end of port 66.
  • Radial passageway establishes communication between axial passageways 46 and 146 in plugs 42 and 142, respectively, and the exterior of the handball.
  • H6. 2 shows the underside of handball 10. Opening 12, with control lever 14 seated therein, is visible at the left, and exhaust port 66 is seen in proximity to opening 12.
  • Plug 142 is hexagonal in shape at its outermost surface, and plug 42 is similarly shaped.
  • the single inlet conduit 60 abuts against the hexagonal nut that retains nipple 62 in position and communicates with bores 16 and 18, as previously noted.
  • First signal port 55 communicates with axial passageway 47, while second signal port 155 communicates with axial passageway 146.
  • FIG. 3 is a view, on an enlarged scale, of a detail of bore 16 showing the metering or modulating valve in its normal, unactuated position.
  • the unactuated position indicates that trigger lever 20 is in its home position of FIG. 1.
  • washer 40 In its unactuated position, washer 40 is positioned approximately 0.01 inch away from valve seat 44, so that pressurized air that passes ball valve 56 will flow past seat 44, into passage 64, and then exit through exhaust port 66.
  • FIG. 4 is taken along a line of sight parallel to the line of sight utilized in FIG. 2. In addition to exhaust port 66, FIG. 4 shows radial passage 54 which connects annular passageway 52 to first signal port 55 and radial passage 154 which connects annular passageway 152 to second signal port 155.
  • FIG. 5 is taken along a line of sight parallel to the lines of sight utilized in FIGS. 2 and 4.
  • the clearance between washer 26 held in place on the lower end of plunger 24 by snap ring 28 and cavity 32 in spacer 34 is visible.
  • the clearance between washer 126 and cavity 132 in spacer 134 is also visible.
  • Trigger lever 20 can be manually pivoted through the arc indicated by the directional arrows. As shown in dotted outline, knee 260 on lever 20 is resting by its own weight on the upper end of plunger 24 in its home, unactuated position. At all other times, knee 20a bears against the upper end of plunger 26. Conduit 60 secured to nipple 62 introduces pressurized air from a re mote source, not shown, into the interior of handball 16.
  • plunger 24 When trigger lever 20 is in its neutral, or home position, plunger 24 is urged upwardly by check valve spring 58 to a position in proximity to knee 20a on lever 20.
  • the pressurized air supply entering handball through conduit 60 travels but a short distance before encountering ball check valve 156 which is biased into engagement by lower control spring 158 with a shoulder in passageway 146.
  • Some of the air escapes past valve 156 and travels axially upwardly through passageway 146, flows between seat 144 and washer 140 and exits through exhaust port 66.
  • knee 20a on the lever presses against the upper surface of plunger 24 to overcome the bias of spring 30 and shift the plunger downwardly a short distance until washer 40 engages seat 44 in plug 42.
  • the extent of movement required for the washer to contact the seat is 0.010 inches, although this distance is not a critical one.
  • Trigger lever 120 functions in the same manner and generates a variable air pressure signal at second signal port 1155.
  • the pneumatic circuit of FIG. 7 schematically depicts the relationship of handball 10 to the remainder of the pneumatic control system that, in turn, controls the operation of the hydraulic control valve which governs the performance of machine functions for a mobile construction machine.
  • pressurized air from a supply source, such as a compressor, is fed to pressure regulator 200.
  • the pressurized air is supplied to regulator 200 at 85l20 p.s.i. and the regulator reduces the pressure to 35 psi.
  • the pressurized air then. passas through conduit 60 into handball 10.
  • Flow through handball 10 is substantially blocked by spring loaded ball valve 56 in axial passageway 46 when trigger lever 20 is in its normal, unactuated position, as indicated by the dotted lines.
  • variable pressure air signal flows into amplifierregulator 202, which is pressurized from the power source at -120 p.s.i.
  • the air signal adjusts the air signal exiting from amplifier-regulator 202 to a lever ranging from 30-105 p.s.i., the pressure regulation function being achieved in a 3:1 ratio.
  • regulator 202 could be omitted from the circuit and the air signal from handball 10 could be used to directly operate another device.
  • the air signal then passes through quick release valve 204 and actuates air cylinder 206 which is connected to hydraulic control valve 208.
  • Valve 204 may be omitted from the pneumatic circuit, if desired if the valve 202 does not provide additional response towards the center portion of valve 208.
  • Actuation of air cylinder 206 provides the impetus necessary for operation of hydraulic control valve 208. Operation of valve 208 governs, in turn, the operation of hydraulic cylinder 210 which controls the functions performed by construction machines. By virtue of the above described circuitry, the speed of movement of cylinder 210 is proportional to the magnitude of the air pressure signal present at first signal port 55.
  • Trigger lever controls an identical, but separate, pneumatic circuit (not shown) in an identical manner by means of the air pressure signal present at second control port 155.
  • Trigger lever 120 proportionately controls a second air cylinder 212, which adjusts hydraulic control valve 208 and thus hydraulic cylinder 2110.
  • Valve 208 may assume the form of a spool valve which could be readily retained in a central position by unactuated air cylinders 206 and 212, and could easily be shifted in either direction from such position in response to a low level air signal at air cylinders 206 or 212.
  • the hydraulic fluid for cylinder 212 is retained in reservoir 2113.
  • FIGS. 1-7 show handball 10 secured to the upper end of control lever 14
  • FIG. 8 shows the handball and lever in combination with a mobile construc tion machine.
  • the handballs and/or levers can be adapted to function remotely by utilizing quick connect-disconnect joints and elongated conduits (not shown).
  • the ready removability of either or both of these components can be of particular significance when digging a deep trench or when laying pipe in such trench with a backhoe. With conventional controls, the machine operator often is unable to see down into the trench and must estimate the position the backhoe bucket has assumed.
  • the provision of readily detachable control units and related pneumatic control circuitry would permit machine operator mobility for peering into the trench for carefully and accurately controlling the functions of the mobile construction machine.
  • a mobile construction machine pressure responsive pneumatic circuitry including inlet means and outlet means for controlling the functions of said machine, and a handball for producing a variable pressure signal, said handball comprising:
  • a body including an axial bore extending therethrough
  • said body also including an inlet port, an exhaust port, and a signal port communicating with said axial bore, said signal port being connected to the inlet means of said pneumatic circuitry,
  • annular valve seat being defined at the inner end of said plug
  • plunger means mounted for axial movement within said bore between unactuated and fully actuated positions, said plunger means located in proximity to said trigger means
  • valve means situated within said axial bore for metering the flow of fluid passing between said inlet port and said exhaust port, said valve means including a first washer operatively connected to said plunger means for axial movement relative to said valve seat,
  • said trigger means when actuated, moving said plunger means and said first washer toward said valve seat to produce a modulated pressure signal at said signal port that is fed to the inlet means of said pneumatic circuitry, said signal being proportional to the extent of movement of said plunger means.
  • said plunger means within said handball includes a cylindrical plunger and said valves means includes, spacer means disposed in operative relationship to said plunger, and means interconnecting the plunger and the spacer means so that they move in concert with one another.
  • said spacer means comprises a body member having a top wall, a bottom wall, an annular wall joining the top and bottom walls, a cavity formed in the top wall and extending downwardly toward the bottom wall, and an opening in the bottom wall extending upwardly toward said cavity, said pin being adjustably inserted into said opening in said body member.
  • a mobile construction machine pressure responsive pneumatic circuitry including inlet means and outlet means for controlling the functions of said machine, and a handball for producing a variable pressure signal, said handball comprising:
  • a body including an axial bore extending therethrough
  • said body also including an inlet port, an exhaust port, and a signal port communicating with said axial bore, said signal port being connected to the inlet means of said pneumatic circuitry,
  • plug means secured within the end of the axial bore opposite to said trigger means, said plug means having an axial passage for establishing communication between said bore and said inlet port,
  • plunger means mounted for axial movement within said bore, said plunger means located in proximity to said trigger means,
  • said plunger means including a cylindrical plunger, spacer means disposed in operative relationship to said plunger, and means interconnecting the plunger and the spacer means so that they move in concert with one another,
  • said spacer means includes a pin adjustably secured thereto and extending away from said spacer means into contact with said check valve means,
  • supply means connected to said inlet port for delivering pressurized fluid thereto
  • valve means situated within said axial bore for metering the flow of fluid passing between said inlet port and said exhaust port.
  • said trigger means when actuated, moving said plunger means to close said valve means and produce a pressure signal at said signal port that is fed to the inlet means of said pneumatic circuitry.
  • a pneumatic control for controlling functions of a mobile construction machine comprising:
  • a body including an axial bore extending therethrough
  • said body also including an inlet port, an exhaust port and a signal port communicating with said axial bore,
  • manually actuatable plunger means mounted for axial movement within said bore between unactuated and fully actuated positions, supply means connected to said inlet port for delivering fluid under pressure thereto,
  • valve means in said bore for substantially closing said inlet port from said exhaust and signal ports when said plunger means is in said unactuated position
  • valve actuating means located in said bore
  • said control comprising:
  • a body including an axial bore extending therethrough
  • said body also including an inlet port, an exhaust port and a signal port communicating with said axial bore,
  • valve means in said bore for substantially closing said inlet port from said exhaust and signal ports when said plunger means is in said unactuated positron
  • valve actuating means located in said bore and being connected to said plunger means for concurrent movement of said plunger and said valve actuating means to open said valve means, upon actuation of said plunger means, and
  • pressure modulating means including a sealing element mounted on said valve actuating means for concurrent movement therewith into contact with an annular seat in said bore to increasingly restrict flow from said inlet to said exhaust ports as said plunger is moved from its unactuated position toward its fully actuated position,- thus increasing the pressure at said signal port proportionally with the extent of movement of said plunger.

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  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Operation Control Of Excavators (AREA)
  • Mechanically-Actuated Valves (AREA)
  • Portable Nailing Machines And Staplers (AREA)
US3773084D 1971-11-04 1971-11-04 Control for mobile construction machine Expired - Lifetime US3773084A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US19558171A 1971-11-04 1971-11-04

Publications (1)

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US3773084A true US3773084A (en) 1973-11-20

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Application Number Title Priority Date Filing Date
US3773084D Expired - Lifetime US3773084A (en) 1971-11-04 1971-11-04 Control for mobile construction machine

Country Status (6)

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US (1) US3773084A (ja)
JP (2) JPS4854702A (ja)
CA (1) CA996000A (ja)
FR (1) FR2158501B1 (ja)
GB (1) GB1394440A (ja)
IT (1) IT970144B (ja)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3927603A (en) * 1972-06-12 1975-12-23 Koehring Co Control means for a pair of fluid motors
US3958495A (en) * 1972-08-31 1976-05-25 Koehring Company Air-oil amplifier
US20110062702A1 (en) * 2008-05-16 2011-03-17 Pellin Christopher J Hose manifold with integrated filtration and shut-off check valves
US20120037246A1 (en) * 2009-03-31 2012-02-16 Carlisle Brake Products (Uk) Ltd. Twin power valve with integrated pressure balance

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5099132U (ja) * 1974-01-22 1975-08-18
JPS56110433U (ja) * 1980-01-28 1981-08-26
FR2557218B1 (fr) * 1983-12-21 1988-01-15 Bennes Marrel Emetteur hydraulique de commande a distance avec amplificateurs de debit

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2346820A (en) * 1933-11-08 1944-04-18 Bendix Westinghouse Automotive Power gear shifting mechanism
US2478002A (en) * 1943-12-31 1949-08-02 Int Harvester Co Valve structure manipulatable for controlling delivery of fluid at selective pressures
US2535785A (en) * 1946-08-29 1950-12-26 Couri George Fluid operated press and control therefor
US2923518A (en) * 1953-08-27 1960-02-02 Goodrich Max Hydraulic duplicating mechanism for machine tools and the like
US3019816A (en) * 1960-03-23 1962-02-06 Bendix Corp Control valve for dual independently operable braking systems
US3054386A (en) * 1959-02-13 1962-09-18 Gen Motors Corp Brake booster unit
US3446376A (en) * 1967-04-27 1969-05-27 Eaton Yale & Towne Reversing mechanism for industrial vehicle

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0717408U (ja) * 1993-09-03 1995-03-28 株式会社三精工作所 微細孔加工装置

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2346820A (en) * 1933-11-08 1944-04-18 Bendix Westinghouse Automotive Power gear shifting mechanism
US2478002A (en) * 1943-12-31 1949-08-02 Int Harvester Co Valve structure manipulatable for controlling delivery of fluid at selective pressures
US2535785A (en) * 1946-08-29 1950-12-26 Couri George Fluid operated press and control therefor
US2923518A (en) * 1953-08-27 1960-02-02 Goodrich Max Hydraulic duplicating mechanism for machine tools and the like
US3054386A (en) * 1959-02-13 1962-09-18 Gen Motors Corp Brake booster unit
US3019816A (en) * 1960-03-23 1962-02-06 Bendix Corp Control valve for dual independently operable braking systems
US3446376A (en) * 1967-04-27 1969-05-27 Eaton Yale & Towne Reversing mechanism for industrial vehicle

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3927603A (en) * 1972-06-12 1975-12-23 Koehring Co Control means for a pair of fluid motors
US3958495A (en) * 1972-08-31 1976-05-25 Koehring Company Air-oil amplifier
US20110062702A1 (en) * 2008-05-16 2011-03-17 Pellin Christopher J Hose manifold with integrated filtration and shut-off check valves
US20120037246A1 (en) * 2009-03-31 2012-02-16 Carlisle Brake Products (Uk) Ltd. Twin power valve with integrated pressure balance
US8550116B2 (en) * 2009-03-31 2013-10-08 Carlisle Brake Products (Uk) Ltd. Twin power valve with integrated pressure balance

Also Published As

Publication number Publication date
JPS5214701U (ja) 1977-02-02
FR2158501B1 (ja) 1975-03-28
FR2158501A1 (ja) 1973-06-15
IT970144B (it) 1974-04-10
JPS5421841Y2 (ja) 1979-08-02
DE2252693B2 (de) 1976-05-26
CA996000A (en) 1976-08-31
DE2252693A1 (de) 1973-05-10
GB1394440A (en) 1975-05-14
AU4803872A (en) 1974-04-26
JPS4854702A (ja) 1973-08-01

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Legal Events

Date Code Title Description
AS Assignment

Owner name: KOEHRING COMPANY 200 EXECUTIVE DRIVE, BROOFIELD, W

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:KOEHRING COMPANY A WI CORP.;REEL/FRAME:003995/0514

Effective date: 19810505

AS Assignment

Owner name: BANK OF NEW ENGLAND NATIONAL ASSOCIATION

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:KOEHRING CRANES & EXCAVATORS, INC., A CORP. OF DE.;REEL/FRAME:004682/0002

Effective date: 19870115

AS Assignment

Owner name: KOEHRING CRANES & EXCAVATORS, INC., A CORP. OF DE

Free format text: RELEASED BY SECURED PARTY;ASSIGNOR:BANK OF NEW ENGLAND NATIONAL ASSOCIATION;REEL/FRAME:005271/0248

Effective date: 19900111

AS Assignment

Owner name: IBJ SCHRODER BANK & TRUST COMPANY, NEW YORK

Free format text: SECURITY INTEREST;ASSIGNOR:TEREX CORPORATION;REEL/FRAME:006080/0201

Effective date: 19920327

AS Assignment

Owner name: TEREX CORPORATION, CONNECTICUT

Free format text: RELEASE OF SECURITY INTEREST AND REASSIGNMENT;ASSIGNOR:IBJ SCHRODER BANK & TRUST COMPANY, AS AGENT;REEL/FRAME:007312/0374

Effective date: 19920731