Control Means For Hydraulic Tilting Mechanism Patents (Class 298/22C)
  • Patent number: 5842823
    Abstract: A bale-accumulating trailer is connectable to a baler for forming round bales of agricultural crop material. The trailer includes a fixed frame having a set of ground-engaging wheels, and a dumping frame pivotably mounted to the fixed frame for movement between a bale accumulating position and a bale dumping position in response to operation of a dumping cylinder assembly. A bale transfer mechanism functions to receive bales discharged from the baler and to place the formed bales onto the dumping frame. The bale transfer mechanism includes a carriage movable between a forward position and a rearward position in response to operation of a cylinder assembly. A bale receiver is mounted to the carriage, and is movable between a bale receiving position and an upright position in response to operation of a pair of cylinder assemblies.
    Type: Grant
    Filed: November 14, 1997
    Date of Patent: December 1, 1998
    Assignee: Gehl Company
    Inventors: Richard Kohnen, Eric St-Denis, Patrick Provost
  • Patent number: 5788333
    Abstract: In hydraulic or mechanical systems, remote controllers are used to actuate and then control the systems. For instance, in dump vehicles, a controller controls a hydraulic or mechanical actuator that is used to raise and lower the bed during the dumping cycle. A locking safety feature is provided on such a controller to assure that accidental or too rapid of dumping does not occur. This controller provides stops that prohibit additional actuation of the bed absent override. The locking safety feature includes a button within the knob that allows for one-handed operation.
    Type: Grant
    Filed: September 6, 1996
    Date of Patent: August 4, 1998
    Assignee: Buyers Products Company, Inc.
    Inventors: Mark J. Saltzman, Thomas A. Gries
  • Patent number: 5769502
    Abstract: The present invention relates to a levelling system for motor vehicles which allows the shaft that hinges a truck body or other loading surface defining a loading structure, to an auxiliary frame defining, or forming part of, the vehicle's supporting structure, to remain horizontal so as to enable the body or loading surface to be used effectively; the levelling system basically includes a device for detecting the inclination of the hinge shaft to the horizontal and a mechanism for adjusting the inclination consisting of a bracket or lever placed between the supporting structure and the loading structure, pivoted to a second shaft and operated on by at least two variable extension elements connected to the supporting structure and designed to vary the inclination of the latter in accordance with the readings of the detecting a mechanism.
    Type: Grant
    Filed: May 23, 1996
    Date of Patent: June 23, 1998
    Inventor: Marco Bettini
  • Patent number: 5742228
    Abstract: A system for preventing the overturning of the bin of a tipper truck during the raising of the bin for purposes of unloading includes a lateral level sensor to sense the lateral orientation of the tipper truck, and a longitudinal level sensor for sensing the longitudinal inclination of the bin. A processor processes the outputs of the lateral and longitudinal level sensors to derive a measure of risk of overturning. The system also includes a display for displaying an indication responsive to the measure of risk. The processor preferably processes the output of the lateral level sensor to calculate a rate of change of lateral inclination of the tipper truck. Optionally, a mechanism may be provided for interrupting the raising of the bin, the mechanism being responsive to the processor.
    Type: Grant
    Filed: September 4, 1996
    Date of Patent: April 21, 1998
    Assignee: Litan Advanced Instrumentation Ltd.
    Inventor: Nisim Levy
  • Patent number: 5720526
    Abstract: A device and method for locking a slidable and tiltable truck bed against tilting when the truck bed is in the forward position adjacent the truck cab are presented. The device includes a movable actuator that communicates with the truck's hydraulic system to effect tilting. If this actuator is prevented from moving, the tilting function cannot be accessed. The actuator is locked by restraining its top end between two tabs at one end of a hinge. A spring positioned between a fixed support, to which is also affixed the other end of the hinge, and one of the tabs, in the absence of compression, permits the actuator free motion; upon a forward sliding of the truck bed, however, the spring is compressed, moving the tabs downward to engage and restrain the actuator top end.
    Type: Grant
    Filed: April 19, 1996
    Date of Patent: February 24, 1998
    Inventor: Donald D. Roberts
  • Patent number: 5588712
    Abstract: A device and method for automatically lowering the bed of a dump truck by disengaging the hydraulic pump and the power take-off when the transmission of the dump truck is shifted to or above a predetermined gear. A conventional dump truck or transmission system is utilized.
    Type: Grant
    Filed: June 21, 1995
    Date of Patent: December 31, 1996
    Inventor: Louie J. Brooks
  • Patent number: 5452942
    Abstract: A device and method for automatically lowering the bed of a dump truck by disengaging the hydraulic pump and the power take-off when the dump vehicle reaches or exceeds a predetermined speed or when the transmission is shifted to or above a predetermined gear. A conventional dump truck speedometer or transmission system is utilized.
    Type: Grant
    Filed: August 2, 1993
    Date of Patent: September 26, 1995
    Inventor: Louis J. Brooks
  • Patent number: 5383714
    Abstract: A vehicle is provided with a dump bed which can be pivoted from a horizontal orientation to a fully upright position to facilitate loading of material onto the dump bed and unloading material therefrom. A hydraulic or other type cylinder is used to raise and lower the dump bed. The cylinder is oriented at an acute angle from the horizontal and is attached at one end to a rear portion of the dump bed. The other end of the cylinder is attached to a crossbeam at a forward location. The dump bed includes downward extending arms and extensions that carry pivot pins about which the dump bed rotates. The location of the pivot axis in this manner creates a crank arm that provides the cylinder with the leverage necessary to raise the dump bed.
    Type: Grant
    Filed: November 9, 1992
    Date of Patent: January 24, 1995
    Inventor: H. Victor Hunter
  • Patent number: 5305782
    Abstract: A pneumatic control valve system has a modulating valve and a piston. When the operator depresses the piston, pressure is communicated to a switching piston moving that piston to a switched position so that pressure is communicated to a switching outlet. The switching piston retains this switched position when the first piston is released. When the modulating valve is opened to communicate pressure to a work port, pressure is also communicated to the switching piston in order to move the switching piston back to its unswitched position whereat the switching outlet is vented. The switching piston allows the control of another function.
    Type: Grant
    Filed: January 22, 1993
    Date of Patent: April 26, 1994
    Assignee: Diesel Equipment Limited
    Inventors: Graham V. Kipling, Paul H. Martin
  • Patent number: 5299856
    Abstract: A dump vehicle, such as for agricultural use, includes a movable support member and a slide structure for supporting and guiding the support member, a container pivotally mounted to the support member, a hydraulic actuator mechanism actuable to lift the container from an original lowered position to a predetermined raised position and to tilt the container at the support member when in the predetermined raised position to a preselected tilted position to permit discharge of the contents of the container. The dump vehicle further includes a hydraulic lock mechanism actuable in response to tilting of the container towards the tilted position to lock the support member in the predetermined raised position to prevent over centering and downward movement of the container from the predetermined raised position during tilting and discharging of the container.
    Type: Grant
    Filed: May 17, 1991
    Date of Patent: April 5, 1994
    Assignee: Richardton Manufacturing Company (Div. of Core)
    Inventor: William R. Grosz
  • Patent number: 5141288
    Abstract: A side dumping loading bucket for pivoting a dumping bucket about a plurality of axes automatically includes a bucket having first and second sides oriented perpendicular to the centerline of the bucket, a holder having first and second sides and a second centerline substantially parallel to the centerline of the bucket, a dumping ram disposed substantially parallel to the centerline of the bucket and operatively connected between the bucket and the holder for dumping the bucket on a selected side, first and second journal assemblies located on the first and second sides of the holder and concentric with the axes and a hydraulic circuit including the dumping ram and the first and second journal assemblies for locking a selected journal assembly prior to unlocking the other journal assembly and for operating the dumping ram only after the selected and the other journal assemblies are locked and unlocked, respectively.
    Type: Grant
    Filed: January 7, 1991
    Date of Patent: August 25, 1992
    Assignee: Nordiska Industrimaskiner AB
    Inventor: Rutger Smith
  • Patent number: 5065569
    Abstract: An interlock system for a telescoping dumping basket on a cotton harvester includes a rotary control valve which controls basket telescoping and unloading functions. A lever on the basket operates an interference lock restricting rotation of the control valve away from the telescoping position toward an unloading position when the basket is retracted a preselected amount toward a compact storage position. The lever is connected through a push-pull cable to the lock on the valve so that valve rotation is mechanically restricted when the basket is retracted.
    Type: Grant
    Filed: July 17, 1990
    Date of Patent: November 19, 1991
    Assignee: Deere & Company
    Inventor: Francis E. Schlueter
  • Patent number: 5062759
    Abstract: A safety circuit arrangement for use with lifting/tilting devices for emptying garbage containers into garbage trucks. To prevent the manipulation of switches such as flap and acknowledgement signal switches provided on such lifting/tilting devices, for the safety of the operating personnel, these switches are connected to a current flow monitor 25 which is electrically connected to an automatic control unit 30 for the automatic emptying of the garbage containers. This current flow monitor 25 transmits a "clear" signal to the automatic control unit 30 only if the flap and acknowledgement switches 16 and 11 are in their intended positions. In addition, other safety switches may be provided, such as lower and upper reference switches 9 and 32, respectively and a barrier switch 13.
    Type: Grant
    Filed: March 30, 1990
    Date of Patent: November 5, 1991
    Assignee: Zoller-Kipper GmbH
    Inventor: Hans J. Pieperhoff
  • Patent number: 5044861
    Abstract: A container truck, preferably a garbage-collecting truck, provided with a replaceable container which is connected by a releasable coupling to a tiltable frame which is pivotally movable by at least one first hydraulic fluid-operable piston-cylinder unit relative to the main frame of the chassis of the truck about a transverse axle, which axle connects the two frames and which axle is located at the rear end portion of the two frames. The container is movable along the tiltable frame on longitudinal tracks or on a slider for an extending movement toward the rear end of the truck or for a retracting movement toward the driver's cab of the truck by a second piston-cylinder unit. The truck also includes structure for switching the second hydraulic fluid-operable piston cylinder unit to a floating condition.
    Type: Grant
    Filed: October 31, 1990
    Date of Patent: September 3, 1991
    Assignee: Edelhoff Polytechnik GmbH & Co.
    Inventors: Johannes Kirchhoff, Georg Sandkuhler
  • Patent number: 5020857
    Abstract: A fluid dynamic restrictor limits the speed at which the bed of a dump truck can be lowered by discharging fluid from a lift cylinder. The fluid dynamic restrictor defines a fluid vortex that provides a pressure drop proportional to the square of the fluid flow rate. Therefore the maximum rate at which the bed can be lowered is much the same regardless of whether the bed is empty or full. In contrast to a restrictor in the form of a throttled valve or wire mesh, the fluid dynamic restrictor is not easily plugged by debris. The fluid dynamic restrictor also offers little resistance in its reverse direction, which facilitates rapid lifting of the bed.
    Type: Grant
    Filed: January 23, 1990
    Date of Patent: June 4, 1991
    Inventor: Peter C. Bertelson
  • Patent number: 5006033
    Abstract: A carrier vehicle, for carrying at least one vehicle on a carrier bed which is slidable and tiltable relative to the carrier vehicle's frame, includes a tilt lock-out arrangement for preventing actuation of the carrier vehicle's tilt cylinders whenever the moveable carrier bed is locked in a stowed, or vehicle carrying position. The lock-out arrangement features a contactless sensor element which determines the slidable position of the movable carrier bed and inhibits hydraulic activation of the tilt cylinders to raise or lower the carrier bed unless the carrier bed has first been slid rearwardly to clear a mechanical hold-down element. Similarly, the contactless sensor element inhibits hydraulic actuation of the tilt cylinder to lower the carrier bed unless the bed has cleared the hold-down element.
    Type: Grant
    Filed: July 7, 1989
    Date of Patent: April 9, 1991
    Assignee: Century Wrecker Corporation
    Inventor: Ralph E. McConnell
  • Patent number: 4930297
    Abstract: Cotton harvester basket structure including an upper basket portion telescopingly received within a lower basket portion and first hydraulic actuators for moving the basket between harvesting and dump positions and second actuators for telescoping the basket portions between a retracted storage position and an extended field-working position. An unloading conveyor and compacting augers are connected to and movable with the upper basket portion, and the compacting augers also serve to meter cotton during the dump cycle. Telescoping cotton conveying ducts are movable with the upper basket portion between retracted transport and raised field-working positions. Hydraulic circuitry includes valves for selectively controlling the basket telescoping and dump functions and the conveyor and compacting auger operations.
    Type: Grant
    Filed: October 11, 1988
    Date of Patent: June 5, 1990
    Assignee: Deere & Company
    Inventors: Francis E. Schlueter, Kenneth C. McConnell, Steve A. Junge, Steve H. McBee
  • Patent number: 4898427
    Abstract: A neutral stop device is provided which prevents the accidental lowering of a truck bed when the spool of the hydraulic valve system is positioned in a neutral location and any force acts on a pull-out cable running from the spool to the truck bed. A stop device is provided having two annular rings, each of which surround a different end of the spool, said rings being connected by a spacer means. Each of the annular rings is adapted to interact with a snap ring provided on the end of the spool to restrict the movement of the spool to a preselected range. The stop device is activated by a cable attached to the truck bed and is moved to a position which prevents the spool from moving from a raise location to a lower location.
    Type: Grant
    Filed: November 30, 1988
    Date of Patent: February 6, 1990
    Assignee: Commercial Intertech Coporation
    Inventor: David W. Francis
  • Patent number: 4898333
    Abstract: A hydraulic system is provided including a hydraulic pump which is continuously coupled with the engine of a utility such as a dump truck utilized for snow-ice removal. When hydraulic implements employed on the truck are not actuated, the pump operates in a cavitation mode. During this cavitation mode of operation, there is no ingress of air through seals or the like to a venting of the gear pump chamber essentially to tank or atmosphere. A poppet valve is actuated in conjunction with periodic use of hydraulic elements on the truck to actuate the pump to an operational or pressurized mode. A key actuated calibrating system is employed to calibrate snow-ice removal components in a secure manner. Calibration is provided in conjunction with EEPROM memory.
    Type: Grant
    Filed: August 30, 1988
    Date of Patent: February 6, 1990
    Assignee: H.Y.O., Inc.
    Inventors: James A. Kime, Gregory R. McMenamin
  • Patent number: 4865389
    Abstract: In a motor vehicle such as a truck or the like having a battery-operated low voltage electrical system, an hydraulically powered system for operating one or more high power hydraulic rams or the like and a pneumatic system for regulating the operation of the hydraulic system, the improvement wherein the pneumatic system is powered by a low capacity compressor which is powered by a low voltage electric motor which is electrically connected to the low voltage circuit of the motor vehicle to drive the compressor to pressurize the pneumatic system as required in use.
    Type: Grant
    Filed: December 30, 1987
    Date of Patent: September 12, 1989
    Assignee: Diesel Equipment Limited
    Inventor: John C. Martin
  • Patent number: 4865079
    Abstract: A high pressure hydraulic flow control valve is formed with a spool which is capable of operating as a conventional spool to control the flow of fluid from an input port to an output port or to a return port. The spool also provides overload protection which will permit fluid to pass from the input port directly to the return port when an overload pressure condition exists in the fluid supply line. In alternative structure, the overload pressure release system may be incorporated into the valve which is used to control the return of fluid from the output port to the return passage. The high pressure hydraulic flow control valve is formed from a die-cast housing and has hardened seats mounted in access passages so as to bear against a seating shoulder. Preferably, a retaining sleeve is mounted in the access passage to bear against the hardened seat to retain it against the seating shoulder.
    Type: Grant
    Filed: February 27, 1989
    Date of Patent: September 12, 1989
    Assignee: Diesel Equipment Limited
    Inventors: Paul H. Martin, John C. Martin, Roy G. R. Furzer
  • Patent number: 4825909
    Abstract: A high pressure hydraulic flow control valve is formed with a spool which is capable of operating as a conventional spool to control the flow of fluid from an input port to an output port or to a return port. The spool also provides overload protection which will permit fluid to pass from the input port directly to the return port when an overload pressure condition exists in the fluid supply line. In alternative structure, the overload pressure release system may be incorporated into the valve which is used to control the return of fluid from the output port to the return passage. The high pressure hydraulic flow control valve is formed from a die-cast housing and has hardened seats mounted in access passages so as to bear against a seating shoulder. Preferably, a retaining sleeve is mounted in the access passage to bear against the hardened seat to retain it against the seating shoulder.
    Type: Grant
    Filed: February 24, 1988
    Date of Patent: May 2, 1989
    Assignee: Diesel Equipment Limited
    Inventors: Paul H. Martin, John C. Martin, Roy G. R. Furzer
  • Patent number: 4756658
    Abstract: A carrier vehicle for carrying at least one car or the like on a platform slidable and tiltable relative to a fixed bed includes hold-down devices for locking the platform against tilting when the platform is in a rest position in the forward end of the bed. Hydraulic cylinders selectively slide the platform and tilt the platform by separate control rods which are manually actuated. The vehicle includes a safety device for preventing tilting of the platform when the platform is locked by the hold-down devices so as not to break the hold-down devices and for preventing the platform from tilting downwardly onto the hold-down devices when the platform has been slid forwardly but not tilted completely for locking by the hold-down devices. The safety device includes a cam plate fixed to the control rod which effects tilting and a stop plate fastened to a rail forming a portion of the platform.
    Type: Grant
    Filed: April 3, 1987
    Date of Patent: July 12, 1988
    Assignee: Holmes International Inc.
    Inventors: Vernon S. Moore, Kenneth A. Law
  • Patent number: 4569096
    Abstract: A hydraulic system for the components of a street sweeper or the like is disclosed which includes a hydraulic pump and tank connected in series with the motor of an elevator, the motor of a pick-up broom, the motor of a right gutter broom, and the motor of a left gutter broom with each broom motor being driven in response to closing a by-pass valve. The system also includes a control circuit for raising and lowering the several vertically movable components and hydraulics locking them in selected positions. The hydraulic system further includes a hydrostatic drive system including a two-speed shift control assembly.
    Type: Grant
    Filed: December 13, 1984
    Date of Patent: February 11, 1986
    Assignee: FMC Corporation
    Inventor: Denes P. Kassai
  • Patent number: 4508388
    Abstract: A hoist control valve interlock system for trolley-assisted dump trucks prevent a dump vessel from an unexpected upward movement caused by the operator's mismanipulation during running on an ascent course under the trolley mode condition. The interlock system has a pair of air cylinders for controlling a hoist control valve operatively connected to hoist cylinders for the dump vessel and directional control air valves for supplying and discharging compressed air from an air reservoir via a trolley mode interlock valve into and from the air cylinders by the operation of a hoist control lever. When the trolley mode interlock valve is shifted to its engine mode position to its trolley mode position, the hoist control valve is interlocked into its floating position by the action of one of the air cylinders where compressed air is supplied from the air reservoir via the trolley mode interlock valve and a shuttle valve irrespective of the air valves.
    Type: Grant
    Filed: May 26, 1983
    Date of Patent: April 2, 1985
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventor: Teruo Minami
  • Patent number: 4343060
    Abstract: A street sweeper having a frame with a cab carried thereon. An engine is mounted on the frame for powering the sweeper. A series of operating mechanisms are supported on the frame for assisting in a sweepings pick-up operation. A series of hydraulic motors are provided with each being operatively associated with one of the mechanisms for operating the same. A single variable and reversible flow piston pump is operatively connected to the hydraulic motors and the hydraulic mechanisms for operating them at a constant speed. The engine operates the piston pump with a variable speed input. A control mechanism is mounted in the cab, and electrical circuit means is connected between the control mechanism and the piston pump and cooperable with said control mechanism enabling for selective operation of the mechanisms at selective rotational speeds for assisting in a sweepings pick-up operation.
    Type: Grant
    Filed: July 18, 1980
    Date of Patent: August 10, 1982
    Assignee: Elgin Sweeper Company
    Inventors: Donald L. Hildebrand, Ernest F. Prescott
  • Patent number: 4236757
    Abstract: In a control for use in a hydraulic system of the type which includes a hydraulic cylinder arranged to raise and lower a load such as a dump bed of a vehicle, wherein the hydraulic system is actuated for raising and lowering the dump bed upon axial displacement of a rod member contained within an outer conduit from a neutral position in first and second respective axial directions and wherein the hydraulic system is deactivated upon the rod member being in the neutral position. The control includes a tubular member which is adapted to be connected to the outer conduit, a control knob, and a rigid inner member partially within the tubular member having a first end connected to the rod member and a second end supporting the control knob. A latch supported by the tubular member is arranged for releasably locking the inner member in a neutral position with respect to the tubular member for precluding inadvertent axial displacement of the rod member from the neutral position.
    Type: Grant
    Filed: September 29, 1978
    Date of Patent: December 2, 1980
    Assignee: Arens Controls, Inc.
    Inventor: Ted W. Gregory
  • Patent number: 4182534
    Abstract: A system particularly useful in trucks for manipulating a hydraulically operated work station comprising a network of four intercommunicating directional valves including a primary valve directing the flow to or from the work station and located between the work station, a hydraulic fluid pump and a fluid reservoir. The valve is designed so that when in the hold position fluid is continuously circulated from the reservoir through the pump and valve and movement of the work station is prohibited. The primary valve is normally biased to its hold position and is air actuated to its work or return position by an operational valve manipulated by a safety manual control. The operational valve directs air to the work or return side of the primary valve which is provided with free floating pistons for adjusting the primary valve spool in response to the flow of air in a surrounding chamber. The chambers and valve housing cooperate to fully seal the spool against contamination.
    Type: Grant
    Filed: July 15, 1977
    Date of Patent: January 8, 1980
    Inventor: David M. Snyder
  • Patent number: 4084852
    Abstract: A dump truck having a canopy on the dump body which extends over an operator's cab is provided with a latch means for holding the dump body in its lowered transport position and is released only in response to initiating the intentional pivoting of the dump body to its raised position.
    Type: Grant
    Filed: July 22, 1976
    Date of Patent: April 18, 1978
    Assignee: International Harvester Company
    Inventors: John R. Prosek, James C. Tamburino
  • Patent number: 4029359
    Abstract: A cable is connected between the dump body of a dump truck and the movable control member of an hydraulic valve to automatically shift the valve from its "raise" position to its "neutral" position when the dump body approaches its uppermost raised position. There is means to prevent inadvertent transmission of forces from the cable to the movable control member to thereby prevent accidental lowering of the dump body due to an inadvertent pull on the cable.
    Type: Grant
    Filed: April 30, 1975
    Date of Patent: June 14, 1977
    Assignee: The Heil Co.
    Inventor: Norman J. Glomski
  • Patent number: 4003601
    Abstract: The hydraulic valve which controls the hydraulic cylinders in a dump body mechanism has its control member coupled by a cable to the dump body to automatically shift the valve from its "raise" to its "neutral" condition when the dump body reaches its uppermost position when being raised. Two lever arms are pivotally attached to the valve body adjacent to each other, the first lever arm being coupled to the valve control member and to a manual control lever, and the second lever being coupled to the dump body cable. A first abutment is attached to the second lever in position to engage the first lever to move it from its "raise" to its "neutral" position in response to movement of the second lever caused by a pull on the dump body cable.
    Type: Grant
    Filed: January 28, 1976
    Date of Patent: January 18, 1977
    Assignee: The Heil Co.
    Inventor: Ronald B. Gerding
  • Patent number: 3989301
    Abstract: A device for adjusting the rotating angle of a vessel of a dump truck which includes a detent having a guide recess, which is pivotally connected to the vehicle body said detent being connected to a spool of a control valve operated by an operating lever. An arm is pivotally connected to the vehicle body and has a cam follower journaled therein, and another arm is secured to the rod of a cylinder and has a bolt which is secured to said another arm and is adjustable in height. Thus, the shock is absorbed when the vessel is travelling upwards and is stopped.
    Type: Grant
    Filed: March 10, 1975
    Date of Patent: November 2, 1976
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Haruhiko Umeda, Hiroshi Ito, Tadatoshi Mizuno, Yoshiaki Harita
  • Patent number: 3966254
    Abstract: A control structure for neutralizing the transmission of a dump truck when the console switch is in a "reverse" position to prevent the truck operator from inadvertently backing the truck in the event the transmission control is in the "reverse" position at the time the operator accelerates the truck engine to operate the hoist cylinder of the dump body. A conventional dump truck hydraulic transmission system is utilized with the control for the hoisting mechanism being electrically related thereto.
    Type: Grant
    Filed: February 4, 1975
    Date of Patent: June 29, 1976
    Assignee: Caterpillar Tractor Co.
    Inventors: Richard E. Guhl, Kenneth W. Renfro
  • Patent number: RE33835
    Abstract: A hydraulic system is provided including a hydraulic pump which is continuously coupled with the engine of a utility such as a dump truck utilized for snow-ice removal. When hydraulic implements employed on the truck are not actuated, the pump operates in a cavitation mode. During this cavitation mode of operation, there is no ingress of air through seals or the like to a venting of the gear pump chamber essentially to tank or atmosphere. A poppet valve is actuated in conjunction with periodic use of hydraulic elements on the truck to actuate the pump to an operational or pressurized mode. A key actuated calibrating system is employed to calibrate snow-ice removal components in a secure manner. Calibration is provided in conjunction with EEPROM memory.
    Type: Grant
    Filed: October 29, 1990
    Date of Patent: March 3, 1992
    Assignee: H.Y.O., Inc.
    Inventors: James A. Kime, Gregory R. McMenamin