Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
  • F16H61/38—Control of exclusively fluid gearing
  • F16H61/40—Control of exclusively fluid gearing hydrostatic
  • F16H61/46—Automatic regulation in accordance with output requirements
  • F16H61/47—Automatic regulation in accordance with output requirements for achieving a target output speed
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
  • F16H61/38—Control of exclusively fluid gearing
  • F16H61/40—Control of exclusively fluid gearing hydrostatic
  • F16H61/42—Control of exclusively fluid gearing hydrostatic involving adjustment of a pump or motor with adjustable output or capacity
  • F16H61/423—Motor capacity control by fluid pressure control means
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
  • F16H61/38—Control of exclusively fluid gearing
  • F16H61/40—Control of exclusively fluid gearing hydrostatic
  • F16H61/46—Automatic regulation in accordance with output requirements

Definitions

• the present invention provides a variable displacement hydraulic motor control for an industrial vehicle such as a Shovel loader, which is provided with an unloading device S and a variable displacement S hydraulic motor, and is driven by hydraulic pressure.
• an industrial vehicle such as a Shovel loader
• a variable displacement hydraulic motor control device for a continuously variable hydraulic drive vehicle that needs to regulate the maximum speed of the vehicle according to the working conditions
• Figure 1 shows a conventional hydraulic circuit for a continuously variable hydraulic drive vehicle that uses a variable displacement hydraulic pump and motor.
• a part of the output of the engine 5 drives the work machine hydraulic pump 4 and acts on the work machine hydraulic cylinder 52 via the work machine hydraulic circuit 51,
• the remainder of the output of engine 5 drives control pump 3 and hydraulic pump 1
• the hydraulic oil generated by hydraulic pump 1 passes through main circuits 24 and 25.
• the variable displacement hydraulic motor 2 is configured to be rotated therethrough so as to be a driving force of the vehicle.
• 6 is a pump control valve for controlling the capacity of the hydraulic pump 1
• 7 is the same cylinder for controlling the pump capacity
• 8 and 8 are the main relief valves
• 9 is the pump.
• the charge relief valve, 10 is a filter.
• the pressure oil that has passed through the pump control valve 6 and the motor control oil passage 11 is led to one end of the motor control valve 14 and the main circuit 24 and 25 power, and the pilot oil.
• the pressure oil on the high pressure side led by the lot piping 16 is used for the motor capacity control cylinder. Acts to lead to da 31.
• the pump capacity control cylinder 7 and the motor capacity control cylinder 31 are controlled by the pump control valve 6 and the motor control valve 14 so that the hydraulic pump 1 and the hydraulic pump 1 are controlled.
• the speed of the vehicle is changed.
• the traveling drive force and traveling vehicle speed change continuously and continuously, and the maximum drive force (vehicle speed 0) changes to the maximum vehicle speed. It is possible to shift automatically without speed change operation. Therefore, since the driver can control the vehicle speed and driving force only by the accelerator pedal, there is an advantage that the driving operation is easier than a vehicle equipped with a mechanical transmission.
• the working machine pump 4 of the lifting device is also driven by the engine 5 like the hydraulic drive pump 1.
• the lifting speed of the unloading device S is similar to the vehicle speed depending on the pedal angle of the accelerator pedal. Is to be controlled. Therefore, when traveling while raising the lifting device at a narrow work site where the moving distance is short, raise the lifting device at the maximum ascending speed, and hold down the traveling speed at a lower work efficiency.
• the conventional technology there was a major problem in that when the lifting device was raised at the maximum ascending speed, the vehicle speed simultaneously increased to the maximum vehicle speed. In order to compensate for such a problem of matching between the vehicle speed and the unloading speed, conventionally, the motor capacity is fixed to the maximum capacity and the maximum vehicle speed can be reduced.
• the present invention has been made in view of the above circumstances, and its purpose is to reduce traveling performance, which is a characteristic of a continuously variable hydraulic drive vehicle. Another object of the present invention is to provide a variable displacement hydraulic motor control device for a hydraulically driven vehicle capable of continuously controlling the maximum vehicle speed of the vehicle.
• a variable displacement hydraulic motor control device for a hydraulically driven vehicle including a variable displacement hydraulic motor
• the hydraulic pump control device comprising: To the high pressure side of the main circuit joining the pump and the variable capacity hydraulic motor, and to a motor capacity control cylinder for controlling the capacity of the variable capacity hydraulic motor.
• a means is provided for operating to regulate the minimum displacement of the variable displacement hydraulic motor.
• a control device for a variable displacement hydraulic motor is provided.
• the work condition The optimum vehicle speed can be obtained for each case, and a great effect can be obtained in that the matching between the speed of the work equipment such as the unloading device and the traveling speed of the vehicle is greatly improved.
• FIG. 1 is a conventional hydraulic circuit diagram of a hydraulically driven vehicle
• FIG. 2 is a hydraulic circuit diagram of a hydraulically driven vehicle as one embodiment of the present invention
• Fig. 3 is a graph showing the characteristics of the pressure control valve in Fig. 2.
• Fig. 4 is a graph showing the control characteristics of the variable displacement hydraulic motor in the hydraulic circuit shown in Fig. 2.
• Fig. 5 is a graph showing the regulation of the maximum vehicle speed of a hydraulically driven vehicle using the hydraulic circuit shown in Fig. 2, and
• FIGS. 6 and 7 are partial circuit diagrams showing other specific examples of the vehicle speed cut-off device.
• FIG. 2 shows a variable displacement hydraulic pump and a motor according to the present invention.
• FIG. 1 shows a hydraulic circuit of a continuously-variable hydraulically driven vehicle that uses a series of components.
• elements similar to those of the conventional hydraulic circuit shown in FIG. 1 are denoted by the same reference numerals to avoid duplication. The explanation is omitted here.
• the main feature of the hydraulic circuit shown in Fig. 2 is that the vehicle speed cut-off device 122 is added to the conventional hydraulic circuit shown in Fig. 1. That is.
• Pilot piping 15 that guides pressure oil from control knob 3 to motor control valve 14 and pilot piping 1 17 is connected to pressure control valve 11 9 to the one end of the main circuit 24 or the hydraulic oil from the high pressure side of the main circuit 24 or 25 to the motor control valve 14 and the pilot pipe 1 18 to the pressure control valve. 1 1 9 leads to the other end.
• This pressure control valve 119 has a differential pressure between the pressure of the pilot pipe 117 and the pressure of the pilot E pipe 118, and a spring.
• the main circuit was 2 4 or is (that hereinafter referred to as the main circuit pressure) high side pressure P H of 2 5, by Lock DOO since that has led also to the pipe 1 1 8, Roh, Yi Lock door co-emissions collected by filtration over Norre pressure P ST of the pipe 1 1 in 7, the resilient force of the spring 1 2 0 F, pressure control If the pressure receiving area of the pilot pipe 1 18 of valve 1 19 is B and the pressure receiving area of pipe 1 17 is also A,
• Fig. 3 shows the characteristics of this pressure control valve.
• Matching lines of ⁇ 2 and ⁇ 3 have the minimum capacity. Since the minimum motor capacity can be arbitrarily controlled in this way, as shown in Fig. 5, the maximum vehicle speed is continuously controlled between wheels 7 and 7 . ⁇
• FIG. 6 shows another specific example of the present invention, in which only the portion where the vehicle speed cut-off device 122 of FIG. 2 is replaced with 122 ′ is shown. Then, the pressure control valve 1 19 in Fig. 2 is replaced by the electromagnetic pressure control valve 1 1 9 ', and the lever 1 2 1 is replaced by the control device 1 2 1'. In accordance with the command current of the control device 12 1 ′, the above The same characteristics as in Fig. 4 can be obtained.
• FIG. 6 shows still another specific example of the present invention, and shows only a portion where the vehicle speed cut-off device S122 of FIG. 2 is replaced with 122 '.
• a solenoid switch 1 26 and a switch 1 2 1 ′ are used in place of the lever 1 2 1 in FIG. 2, so that the switch 1 2 1 ′ is switched.
• the switch 1 2 1 ′ is switched.
• FIG. 4 only one position in FIG. 4 is switched.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Control Of Fluid Gearings (AREA)
• Motor Power Transmission Devices (AREA)
• Fluid-Pressure Circuits (AREA)
• Operation Control Of Excavators (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=15374798

Family Applications (1)

Country Status (6)

Cited By (1)

Families Citing this family (6)

Citations (1)

Family Cites Families (6)

• 1988
  • 1988-11-08 JP JP1988144985U patent/JP2525386Y2/ja not_active Expired - Lifetime
• 1989
  • 1989-11-08 EP EP89912502A patent/EP0396781B1/en not_active Expired - Lifetime
  • 1989-11-08 US US07/499,447 patent/US5092153A/en not_active Expired - Fee Related
  • 1989-11-08 WO PCT/JP1989/001147 patent/WO1990005254A1/ja active IP Right Grant
  • 1989-11-08 DE DE68920861T patent/DE68920861T2/de not_active Expired - Lifetime
• 1990
  • 1990-07-06 KR KR1019900701448A patent/KR900702271A/ko not_active Abandoned

Patent Citations (1)

Non-Patent Citations (1)

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