Abstract: An apparatus to maintain optimum engine speed and cutter wheel speed to maintain peak power output of the engine and peak flywheel effect of the stump cutter wheel and method for maintaining optimum engine speed. The stump cutter has a rotating cutting wheel powered by an engine, and the cutter is mounted to be moved laterally. The mounting includes a boom and at least a first hydraulic cylinder for urging the boom to move along the path of travel over the surface of a stump. The hydraulic cylinder is activated by a hydraulic circuit which includes a source of pressurized hydraulic fluid. A pressure hydraulic line connects the source of hydraulic fluid to a first port of the hydraulic cylinder and a return line is connected to a second port of the hydraulic cylinder. A valve diverts a portion of flow from the pressure line to the return line or to a sump. The valve is shiftable between at least a first and a second position.

Abstract: A process for transmitting or storing energy in which a gasseous working fluid is compressed and cooled, relative to isentropic compression, by a coolant. The energy used to perform the compression is recovered by expansion, while heat from the coolant is used to reheat the working fluid, thus maximizing efficiency.

Abstract: A carrier vehicle having a swing table supported on an under-carriage so as to swing a full turn, and a planetary reduction gear for reducing the revolution of a drive motor and transmitting it to the swing table. The planetary reduction gear is mounted on the under-carriage under the swing table.

Abstract: An axle driving apparatus housing therein a hydrostatic transmission and axles driven thereby a cooling fan which is provided on a power input shaft of the hydrostatic transmission. A cavity-like through opening is formed in a portion of the housing between the hydrostatic transmission and the axles. The peripheral wall of the opening is formed with a plurality of cooling fins. The cooling fan is rotated by the power input shaft to create wind to cool heat generated in the housing.

Abstract: An electrohydraulic control system that includes a bidirectional electric motor responsive to application of electrical power for rotation in either of two directions, and a hydraulic pump coupled to the motor and having ports for supplying hydraulic fluid in either of two flow directions as a function of direction of rotation of the electric motor. A hydraulic actuator is coupled to the pump for receiving fluid in either of two flow directions and performing work as a function thereof. An electronic controller applies electrical power to the electric motor so as to obtain a desired level of work at the actuator. The electronic controller includes one or more sensors operatively coupled to the actuator for applying electrical power to the motor as a function of motion at the actuator.

Abstract: This invention provides for reliable, long-life operation of fluid pressure responsive engines directly from raw natural gas at the wellhead by introducing a novel rotary dynamic contaminant filter system especially adapted for removing liquid and abrasive particle contaminants from the flow of natural gas under high pressure from the wellhead. Thus, a novel turbine type gas driven rotor in the gas flow stream has rotor blades slanted at an angle to the rotation axis to serve as a ramp for removal of contaminants as the flow of gas spirals upwardly from input to output ports. This dynamic filter employs the combined forces of gravity, centrifugal force and those imposed by interception with a contaminant flow ramp to encounter and remove a wide range of microscopic contaminants from the high pressure wellhead natural gas.

Abstract: The invention concerns a hydrostatic-mechanical gear for driving a mixed drum and, in particular, the drum of a concrete mixer vehicle. Cooling is provided for by the continuous removal of oil from a high pressure circuit, via a connecting pipe, and the constant feeding of the cooled oil, which has passed through an oil cooler, to the interior of a gear housing via a pipe. This pipe discharges into the interior of the gear housing immediately proximate a hydraulic motor. The oil then flows through the hydraulic motor, which is preferably a slow-speed radial piston motor, to reduce the noise generation of the hydraulic motor.

Abstract: A stump cutting or grinding apparatus and method are disclosed which utilize a pump for attachment to a power takeoff of a tractor, a cutting or grinding device for attachment to a backhoe arm of the tractor, a motor connected to the cutting or grinding device, a plurality of lines for circulating hydraulic fluid between the pump and the motor and a plurality of lines for passing a portion of the hydraulic fluid through the hydraulic system of the tractor. Passing a portion of the circulating hydraulic fluid through a hydraulic system of the tractor enables the tractor to cool and filter the fluid and eliminates the need for a separate tank or reservoir that would otherwise be needed to contain and treat fluid being circulated between the pump and motor. A scoop may be attached to the cutting or grinding device for moving or removing rocks, dirt or debris from around the stump.

Abstract: A power steering pump fluid/filter system which utilizes a combined cooler, filter and reservoir that is positioned preferably in front of the radiator and which provides the three functions of reservoir, cooler and filter. The reservoir comprises a body of material such as magnesium or aluminum and has integral cooling fins. The body includes two openings in the base which permits ready connection to the two hoses of the power steering pump. The combined cooler, filter and reservoir also includes a cover typically made of magnesium or aluminum and a cap having a twist lug connection to the cover. The cap supports a dipstick for measuring the level of the oil.

Abstract: A method for cooling hydraulic oil present in an operating circuit of a construction machine, and an installation for cooling hydraulic oil according to the method. The method includes the steps of guiding the hydraulic oil at least partially over an oil cooler and thereafter causing the hydraulic oil to flow into a hydraulic oil tank. The hydraulic oil returning from operating areas of the operating circuit is stored intermediately and has an elevated temperature, the storage occurring in an intermediate reservoir spatially separate from the hydraulic oil present in the hydraulic oil tank prior to causing the hydraulic oil to flow into the hydraulic oil tank. The hydraulic oil is pumped from the intermediate reservoir to the oil cooler for lowering the temperature of the hydraulic oil prior to causing the hydraulic oil to flow into the hydraulic oil tank.

Abstract: An axle driving apparatus of the present invention consists of a hydrostatic transmission for driving a vehicle. The transmission is so designed that a fan is disposed on a power input shaft so as to cool a housing as well as cooling tubing or an oil passage disposed between the fan and the upper surface of the housing. The housing of the axle driving apparatus is filled with lubricating oil, used on the gears and bearings of the power transmission from the hydrostatic transmission to the axles, and operating oil, used in the pump and motor of the hydrostatic transmission. The oil circulates within the tubing or the oil passage. Cooling the oil passing in the tubing or the oil passage prevents a deterioration in efficiency of the axle driving apparatus.

Abstract: The invention is directed to a compressed air control apparatus for supplying compressed air to a pneumatic actuator, which includes a compressor having a head member with a pressure chamber defined therein for generating compressed air, an intake valve for introducing air into the pressure chamber, and a discharge valve for discharging the compressed air. A dryer is disposed in a dry housing to dry the compressed air discharged from the compressor. A supply solenoid valve is disposed in a supply valve housing to control the compressed air supplied to the pneumatic actuator. An exhaust solenoid valve is disposed in an exhaust valve housing to control the compressed air discharged from the pneumatic actuator. The head member, dry housing, supply valve housing and exhaust valve housing are integrally formed by synthetic resin to provide an integral housing.

Abstract: An apparatus to maintain optimum engine speed and cutter wheel speed to maintain peak power output of the engine and peak flywheel effect of the stump cutter wheel. The stump cutter has a rotating cutting wheel powered by an engine, and the cutter is mounted to be moved laterally. The mounting includes a boom and at least a first hydraulic cylinder for urging the boom to move along the path of travel over the surface of a stump. The hydraulic cylinder is activated by a hydraulic circuit which includes a source of pressurized hydraulic fluid. A pressure hydraulic line connects the source of hydraulic fluid to a first port of the hydraulic cylinder and a return line is connected to a second port of the hydraulic cylinder. A valve diverts a portion of flow from the pressure line to the return line or to a sump. The valve is shiftable between at least a first and a second position. In the first position, substantially all hydraulic fluid is passed along the pressure line to the hydraulic cylinder.

Abstract: A regulator for controlling the air pressure of compressed air in an air reservoir which serves as a source of motive compressed air for an air driven device is provided. A method is provided for maintaining sufficient operating pressure of a pressurized air supply tank utilized in air driven systems such as a vehicle braking system.

Abstract: An axle driving system, wherein a first chamber and a second chamber partitioned from each other are formed in a housing, a hydraulic non-stage transmission is housed in the first chamber, axles and means for transmitting power from the transmission to the axles is housed in the second chamber. At the upper portion of the housing is disposed an oil storage tank positioned across the first and second chamber. Oil through-bores for flowing oil therethrough are provided in the first and second chambers respectively. At the oil storage tank are provided means in common to charge oil into each chamber. Means for observing oil quantity, and breather means for ventilating outside air are also provided.

Abstract: An over the highway truck having a power steering system including an improved hydraulic circuit for operation of the system is disclosed. The system includes a heat conductive metal frame element, a power steering pump, and conduits connecting an output of the pump to at least one steering assist actuator. The system also has a heat conductive, metal, hydraulic reservoir defining an internal power steering fluid chamber is connected to the frame element in heat transfer relationship. Supply and return conduits respectively connect the chamber to the pump and the actuator to provide a combination wherein the frame element and reservoir together function as a heat sink to cool power steering fluid. The reservoir has a housing having a base portion and an internally connected, upstanding, circumferentially endless side portion. The housing has flow directing passages adjacent its base portion and communicating with the chamber for delineating fluid flow across the base portion in heat transferring relationship.

Abstract: A stalk and root shredder that is provided with rollers which grasp and move stalks and roots upwardly into the path of rotation of blades which shred the stalks and roots and deposits them back onto the ground surface. The stalk and root shredder is hydraulically powered from pump units mounted directly from the tractor by connection with the power take off spline thereby eliminating the use of a power take off shaft. The hydraulic system includes separate hydraulic motors for driving the rollers and blades with the hydraulic system including a cooling arrangement which maintains optimum operating temperatures of the motor and hydraulic fluid. The stalk and root shredder includes a supporting frame and wheels with this structure being quite similar to that illustrated in my prior U.S. Pat. No. 4,015,667 issued Apr. 5, 1977 with the present invention relating to the improvements in the structure and hydraulic operation of the rollers and blade assemblies mounted over the rollers.

Abstract: An axle driving system, wherein a first chamber and a second chamber partitioned from each other are formed in a housing, a hydraulic non-stage transmission is housed in the first chamber, axles and means for transmitting power from the transmission to the axles is housed in the second chamber. At the upper portion of the housing is disposed an oil storage tank positioned across the first and second chamber. Oil through-bores for flowing oil therethrough are provided in the first and second chambers respectively. At the oil storage tank are provided means in common to charge oil into each chamber. Means for observing oil quantity, and breather means for ventilating outside air are also provided.

Abstract: A hydraulic machine is disclosed in several embodiments as a pump, as a motor, and as a combination pump/motor. The machine's fixed cylinders are positioned circumferentially to a drive shaft, the pistons being driven by, or acting against, a split swash-plate which is supported primarily by the same main bearing in which the drive shaft rotates. The inclination of the split swash-plate is adjusted by an axially-movable servo mechanism which is also arranged circumferentially to the drive shaft. Preferred embodiments include, among other features, (i) various gimballed-yoke supports for the non-rotating portion of the swash-plate, (ii) various designs for a rotating valve-plate, and (iii) a radial valve system. The unique arrangement of elements provides a machine that is remarkably compact and lightweight, being (a) significantly smaller than commercially-available machines having similar horsepower ratings and (b) operable hydrodynamically (i.e., at constant horsepower) at reduced speeds.

Abstract: A hydrostatic machine which includes a housing having an internal space accommodating a rotatably journaled driving mechanism, and wherein the portion of the internal space which is not occupied by the driving mechanism encompasses a drain oil chamber which receives the drain oil inclusive of lubricating oil which is discharged from bearing locations of the hydrostatic machine, and which is connected or port to a tank through at least one drain oil connection of the housing and through a drain oil line.

Abstract: A plunge valve for closing and for opening a connection in a hydraulic conduit comprises a plunge (37) which is slidably movable in the hydraulic conduit (5, 5A) under the influence of the pressure in a section (5A) of the conduit on the inlet side of said conduit adjacent to the plunge between a first, open position, when the pressure in said section (5A) is high, in which position the plunge is withdrawn and communication is established, and a second, closed position, in which the pressure in said section is low, in which position the plunge shuts off said connection.

Abstract: A device for the improvement of the running conditions in a hydraulic installation or in a so-called hydraulic system. The device contains a central circulating circuit separated from the influence of the atmosphere. To the circulating circuit are connected an outlet and an inlet for the connection of the hydraulic fluid to the other part of the hydraulic system. The circulating circuit is divided into at least two chambers separated by respective pressure generating and pressure reducing units. The first chamber is to a certain extent an expansion room for the hydraulic fluid in the system which is separated from the atmosphere and it forms a low-pressure part in the circuit. The second chamber forms a high-pressure part which is directly connected to the outlet. The circulating circuit holds a medium for the cooling and filtering of the hydraulic fluid.

Abstract: In a system for supplying oil to a fluid drive, the fluid drive having an impeller, and a runner fluidically coupled by oil between them, the degree of coupling being determined by the amount of oil between them, a temperature sensor is located to sense the temperature of oil as it is being discharged from the impeller-runner, and the temperature so sensed is translated into the opening and restricting of a control valve controlling the flow of oil to the fluid drive to maintain the discharged oil temperature substantially constant. An external reservoir is connected to the sump of the fluid drive by pipe of sufficient size to provide a head space above the oil being removed from the sump, and the reservoir itself is of such a size as to provide head space and to provide a dwell time long enough to permit detrainment from the oil of air entrained in the oil as it passes through the fluid drive system.

Abstract: The invention relates to a hydraulic system for hydraulic operators for delivering pressurized fluid to a blower drive means and to the hydraulic operators of a hydraulic machine, comprising a variable delivery pump, control valves connecting the hydraulic operators and the blower drive means to the pump, a temperature responsive pressure valve for setting a temperature-proportional control pressure in the pressure line between the blower drive means and the respective control valve, wherein the control valve is subjected to the pressure in the control line in a sense to open the control valve, and a flow volume regulator associated to the variable delivery pump which regulator is subjected via a load sensing line by the load pressure occuring at the hydraulic operators or in the blower drive means depending on which pressure is higher.

Abstract: A fluid distribution device having a circuit including a first and a second duct between a common inlet and a common outlet. A third duct to the first duct and a fourth duct to the second duct. A one-way valve at each side of the connections from the third and fourth ducts to the first and second ducts enables flow from the inlet into each of the third and fourth ducts, but prohibits flow from the third and fourth ducts back to the inlet and only permits the latter flow out of the outlet. Various valves at the inlet and the outlet control pressure. A return path from the outlet to the inlet has a cooler in it. A reservoir supplies fluid.

Abstract: An apparatus powered by solar cell photon energy having a motor for rotating a drive shaft by the use of compressed air. The motor comprising: a housing having a circular cross section with a drive shaft extending therethrough; a rotor having concave cups on its exterior surface mounted on the drive shaft within the housing; ports extending through the housing to cause rotation of the rotor; a plurality of sources of compressed air positioned adjacent to the housing. The apparatus further includes an alternator and/or a system for converting solar energy into mechanical energy comprising a battery chargeable through solar panels to generate power for reciprocating pistons to thereby generate the compressed air.

Abstract: An axle driving apparatus in which an oil sump provided in a housing is vertically partitioned into first and second chambers by partition means constructed in the housing. The first chamber is constructed to have an air layer open to the atmosphere, the second chamber is constructed to be always filled with oil. The first chamber and second chamber can flow oil therebetween through an oil introduction passage of the partition means. When oil volume expands by the temperature during the operation of a hydrostatic transmission, while reducing the volume of the air layer in the first chamber, the oil in the second chamber adjustably flows into the first chamber.

Abstract: The present invention relates to a hydraulic pump system comprising:(a) a variable displacement pump;(b) an engine used to drive the variable displacement pump;(c) a power takeoff unit for engaging or disengaging the engine from the variable displacement pump;(d) a hydraulic motor driven by the variable displacement pump via hydraulic fluid pressure;(e) a liquid pump driven by the hydraulic motor;(f) a hydraulic fluid cooler in communication with the hydraulic motor;(g) a hydraulic fluid reservoir in communication with the cooling means and the inlet the variable displacement pump;(h) hydraulic piping and/or hose for connecting the hydraulic motor, cooler, reservoir and variable displacement pump; and(i) filters located within the hydraulic piping and/or hose.

Abstract: A hydraulic piston type motor having a rotating piston barrel abutting a fixed porting plate or head with a starting charge device including a differential area piston operating to supply a limited hydrostatic pressure between the porting plate and rotating barrel to reduce starting friction and improve starting torque.

Abstract: A system for cooling individual integrated actuator packages (IAPs) positioned throughout the aircraft in a power-by-wire actuation system is disclosed. A low-pressure hydraulic fluid circulates throughout the aircraft to control the temperature of the individual IAPs and to maintain and replenish the hydraulic fluid within the individual IAPs. A thermo-control loop containing low-pressure hydraulic fluid includes a pump, low-pressure hydraulic lines, a heat exchanger, a reservoir and a filter. The entire system provides heat transfer for a high- or low-temperature environment, as may be present on an aircraft. The individual IAPs may be coupled together in series or, alternatively, in parallel, depending upon the design constraints of the system. Compared with distributed hydraulic systems, energy consumption, weight, and cost are significantly reduced by using a low hydraulic pressure for the circulating fluid. Survivability is significantly increased over that provided by a distributed hydraulic system.

Abstract: A lubrication system including a lubricant reservoir connected to a pump assembly which selectively operates in either of two modes of operation. In one mode of operation, the pump assembly provides pressurized lubricant to various lubricant receiving areas. In a second mode of operation, the same pump assembly is used to refill the lubricant reservoir from a lubricant supply source.

Abstract: A vehicle headboard defining a hydraulic oil storage tank for use on a vehicle is disclosed. The vehicle headboard can include a top header, a bottom header, a plurality of spaced apart transfer tubes connected between the top and bottom headers, and mounting brackets attachable to the vehicle. The top header has at least one fluid inlet, a plurality of outlets to the transfer tubes, and receives a portion of hydraulic oil in an interior volume. The bottom header has a plurality of inlets from the transfer tubes, at least one fluid outlet, and also receives a portion of hydraulic oil in an interior volume. The invention is mountable in place of a conventional headboard, and obviates the need for any further hydraulic tank, while placing the storage volume higher than the pump and also improving cooling. The headboard can accommodate various functional storage tank accessories.

Abstract: In a hydraulic drive, in which a double-acting working cylinder (10) is connected to the hydraulic power source by very long working lines (20, 22), it is proposed to connect a bypass line (36) containing a normally closed bypass valve (38) to the ends of the working lines (20, 22) nearest the cylinder. The bypass valve (38) is periodically opened to allow the fluid contained in the working lines (20, 22) to be completely replaced.

Abstract: An automatic lubricating arrangement for a chisel of a hydraulic striking mechanism. A conveying unit is adapted for connection to the chisel guide supporting the chisel of the striking mechanism for charging the chisel guide with lubricating grease and is further connected to the source of operating pressure for the striking mechanism. The conveying unit includes a conveying chamber for receiving lubricating grease and a mechanism for performing a predetermined conveying stroke of adjustable magnitude each time the striking mechanism is charged with operating pressure for forcing lubricating grease out of the chamber and into the chisel guide under pressure derived from the source of operating pressure. A lubricant reservoir for storing lubricating grease is connected to the conveying unit and has a movable separating element and compression spring biasing the separating element against the lubricating grease for supplying lubricating grease to the conveying chamber of the conveying unit.

Abstract: A compressor cooling system is provided for use with an engine PTO driven oil-flooded air compressor. The compressor cooling system includes an oil flow path from the compressor oil outlet, through an oil/coolant heat exchanger, and to the compressor oil inlet. The system further includes a coolant flow path in fluid communication with the engine cooling system with the oil/coolant heat exchanger interposed in the coolant flow path. Thus, coolant flowing through the engine cooling path also flows through the oil/coolant heat exchanger in heat transfer relation with the compressor oil flowing therethrough. The compressor coolant flow path is integrated into the engine cooling system so that flow through the compressor coolant flow path is not interrupted by operation of the thermostatic bypass valve in the engine cooling system.

Abstract: A fluid pressure driven power system having a plurality of rotors keyed to a shaft rotatably journaled within a casing having, the rotors each having a plurality of fins extending around its periphery with the fins projecting above the perimeter of the rotor. A pressure head mounted within the casing with the casing having a plurality of tubular inserts embedded therein. Each of the tubular inserts having an exposed longitudinal end portion in tangential alignment with the fins on a rotor. Each insert end portion having a cutaway section that is upwardly arcuately compressed to overlie the fins on rotors rotating beneath the pressure head. Each compressed cutaway portion is formed with an orifice opening from the tubular insert. A pressurized fluid source can be selectively connected to one or more of the tubular inserts to provide pressurized fluid for discharge through the orifices.

Abstract: A charge flow distribution valve routes all charge pump flow into a main pump until the main pump has sufficient inlet pressure. The valve opens to a first stage which routes excess charge flow to lubrication circuits. At a slightly higher main pump inlet pressure, it also routes oil to an inlet of the charge pump.

Abstract: The problem of sealing a communication bore (56) in a port plate (40) is solved with a self-sealing transfer tube assembly (52). The transfer tube assembly (52) includes a coupling element (64) which is received in a supply bore (60) which intersects the communication bore (56). A relatively small window (78) is provided in the coupling element to provide hydraulic communication between the transfer tube assembly (52) and the port plate porting area (48), while its solid side wall (68) otherwise seals the outer portion of the communication bore (56).

Abstract: A motor vehicle power steering installation has a heat exchanger mounted in a hollow portion of a motor vehicle frame where air passes through at a velocity higher than that outside the motor vehicle frame.

Abstract: An automotive radiator cooling system has a radiator cooling fan driven by a hydraulic motor actuated by a pressurized fluid fed through a hydraulic circuit from an engine-driven hydraulic pump. A bypass line extends in bypassing relationship to the hydraulic motor and has ends connected to the circuit upstream and downstream of the hydraulic motor, respectively. A check valve is provided in the bypass line and is operative to allow a flow of the fluid from a reservoir through the bypass line back into a part of the circuit upstream of the motor only when a pressure drop takes place in that part of the circuit due to free rotation of the cooling fan, and thus of the motor, independently of the drive by the hydraulic pump. The backward flow of the fluid is operative to compensate for the pressure drop to prevent the occurrence of cavitation in the circuit upstream of the motor. Desirably, the bypass line is incorporated into the housing of the hydraulic motor.

Abstract: A hydraulic motor and a hydraulic pump are interconnected by a closed hydraulic circuit. A lubricating chamber is defined around the sliding surfaces of the swash plate and the plungers of at least one of the hydraulic pump and the hydraulic motor. A shuttle valve has two input ports connected to respective oil passages, the shuttle valve being shiftable to connect the one of the oil passages which is of lower oil pressure to the output port of the shuttle valve when the differential pressure between the oil passages is relatively large. A first relief valve is opened to communicate the output port to the lubricating chamber when the oil pressure in the output port exceeds a first pressure level. A second relief valve connected between the first relief valve and the lubricating chamber is opened when the oil pressure between the first relief valve and the lubricating chamber exceeds a second pressure level lower than the first pressure level.

Abstract: A continuously variable transmission employing a hydraulic motor and a hydraulic pump that are interconnected by a closed hydraulic circuit. An oil chamber is defined between the pump cylinder of the hydraulic pump and the motor cylinder of the hydraulic motor. A common oil cooling unit is connected through oil passages to the closed hydraulic circuit and the oil chamber for cooling heated oil supplied therefrom. The common oil cooling unit effectively cools the oil from the two sources since the heat developed in the oil from the two sources generally varies inversely during different modes of operation.

Abstract: A hydraulic power drive unit for connection to the hydraulic system of an agricultural tractor is provided with a pressure release valve to protect the unit seal from damage if connected the wrong way round, and a bleed pipe which bursts to relieve pressure if the pressure release valve fails to operate.

Abstract: A suction type road sweeping vehicle generally has a self propelled chassis with road wheels. Mounted on the chassis is an air tight container for collecting dust etc. swept up by the vehicle. Dust etc. is sucked up into the container via pick up conduits and nozzles, the suction being provided by a fan. When hydraulically driven brushes and the like are used the hydraulic oil must be cooled. This is effected by introducing water into the conduits to mix with the cooling stream of air flowing into the container, separating the cooled water from the air and debris and utilizing the cooled water to cool the hydraulic oil.

Abstract: A fluid motor is connected to a winch at a remote distance from a hydrostatic pump; a scavenge pump is driven by a motor powered by part of the main drive fluid and maintains a lubrication level of fluid also taken from the main drive fluid in the transmission sump at a sufficient level to prevent air contamination of the main drive fluid.

Abstract: In a hydrostatic drive one hydrostatic machine (2 and 4) is adapted for absorbing the sustained braking power or energy. The transmission is furthermore provided with a cooler (9) whose two sides are respectively connected via a threshold pressure valve (7 and 8) with one of two branch ducts (3 and 5) which connect the said hydrostatic machine with a second such machine adapted to act as a drive. The pressure threshold valve is made up of a pressure limiting and check valve.

Abstract: In a hydraulic dual-circuit brake system for motor vehicles, especially high-powered heavy passenger cars, in which the front wheel brakes combined in a front-axle brake circuit are exposed to higher thermal loads than the rearward brakes, brake fluid is conveyed by means of a feed pump to the outlet-pressure space for cooling the front wheel brakes following a braking phase. Circulated brake fluid flows from the master cylinder outlet pressure space assigned to the front-axle circuit, to the wheel brake cylinders, to an additional functional space of the primary piston in the master cylinder, and back to the supply vessel. The circulating fluid pump is controlled by a timing relay which is tripped by the brake-light switch and remains energized for a predetermined time interval to allow sufficient cooling by fluid circulation.

Abstract: A central body connects a driving motor and a pump driven by the driving motor through a shaft and a coupling. The hollow central body surrounds the coupling, connected on one side to the driving motor and connected on the other side to the pump. A fan is arranged in the central body and is connected with an inlet and an outlet. The central body has a heat exchanger through which the outlet from the fan is conducted. To further develop and improve this apparatus, a pressure medium tank is mounted in the central body and surrounds the driving shaft at some distance. The pump is connected with the pressure medium tank through its suction connector. The inlet to the fan is provided on the side of the driving motor.

Abstract: A hydrostatic machine includes a casing (10) containing a rotary member (12) having radial cylinders (24) each with a piston (25) engaging a track ring (27). The member (20) is coupled to an external shaft (13) via reduction gearing (43,44) which also acts as a gear pump. This can be used to supply external power take-off fluid circuits, or an attached oil filter (64) or internal bearings (47,57) or make-up fluid for the machine via valve (42).

Abstract: A transmission casing wherein is inserted a flooded hydromotor has together with an annular space traversed by a forced flow a double function both as oil cooler and as receiver container of the externally situated pumps. Both the working substance flowing out from said hydromotor and the flushing oil that is conveyed past it are led together on intermediate ribs and vanes in a flow channel meanderingly passed about said hydromotor to the filling pump feed pipe. Intermediate ribs and vanes are connected or integral with the transmission casing that has many ribs and can be exposed to a cooling current directed as needed. Said annular space is spatially separated by stop plates from mechanical gear portions eventually situated in front, but is at the same time oil sump thereof by means of a connecting opening.