CN100451336C - Low idling energy consumption hydraulic power source - Google Patents

Abstract

One kind of low energy transfer fluid transmission belonging to a hydraulic power source and control technology, a hydraulic system is to reduce the supply means are in a non-work period and part load conditions the energy consumption and design. The present invention consists of a hydraulic pump (1), the motor (2), the motor speed controller (3), an accumulator (4), solenoid valve (5), a pressure sensor (6), a displacement sensor (7), the controller ( 8), a first hydraulic line (9), a second hydraulic line (10), control valve actuator (11), (12), (13) and other components. Feature of the present invention is a hydraulic pump (1) is a constant pressure pump is variable, which the addition of the displacement sensor may detect the displacement of the pump (7), by changing the rotational speed of the pump allows the power source having a constant voltage and current complex function and constant power control, and reduce power consumption of the rotation speed of the hydraulic system and the non-working portion of the cycle by reducing the load condition of the hydraulic pump.

Description

Low idle power consumption of the hydraulic power source

First, the technical field:

Low idle power consumption of the present invention belongs to a fluid source of hydraulic power transmission and control technology, to provide a certain pressure and flow for the hydraulic actuator power source device.

Second, the technical background:

A hydraulic power source is a fluid power transmission and control system provides for the execution unit, it is converted to mechanical energy with a certain hydraulic pressure and flow energy for driving the hydraulic cylinders and hydraulic motors. Conventional hydraulic power source is fixed speed drive motor or variable pump quantitative composition. In order to match the load, reduce energy consumption, the international development of various forms of variable displacement hydraulic pump. Common variable pump has constant voltage, constant current and constant power three forms. Constant pressure variable pump working characteristics of the system when the operating pressure is below the set pressure of the pump, the maximum pump output flow at a corresponding speed, when the system pressure reaches the set value of the pump pressure, pump output flow rate of the automatic adapt to load requirements, and reduce traffic-related energy consumption. Variable constant pump output coincides with the set value of the flow rate, the pressure is adapted to the load of the system, reducing the energy losses associated with pressure. Constant Power Pump output power limit value of the set coincides with the pump, the pump output flow and pressure of the product remains unchanged. The three pump compared with the power source with a metering pump composed, although to some extent, have reduced the energy consumption of the system, but tests showed that when the system is non-operational periods, such as low pressure pump is unloading large flow of work conditions, a high-pressure pump is a small flow rate and the like, still rated motor speed operation, to a greater energy loss.

In order to reduce non-working cycle, the energy loss due to motor rated speed operation is still due, a new trend is to control the flow and pressure of the pump by changing the speed of the hydraulic pump, control methods have emerged useful AC induction motor, by changing the speed control constant pump output flow and pressure, Europe

Patent Publication No. EP 0752304 Al; asynchronous motor with variable speed, combined with the proportional pressure valve and flow metering pump consisting of a power supply source control system flow and pressure, European Patent Publication No. EP0 509724 Al, their inadequate dynamic slow response; in German Patent DE 3919823 Al, the servomotor control output of the constant pump flow rate and pressure, there is a problem of high costs, which affect the promotion and application; Germany was for AC induction motor with a variable speed a variable displacement hydraulic pump in combination with an electronic control proportional control pump output flow and pressure, there is the high cost is still insufficient, and the composition

The system is also very complicated. Low energy turn a hydraulic power source present invention aims to provide a novel variable speed motor and variable displacement hydraulic pump as a hydraulic power source combinations, i.e., low cost, good dynamic response, but also to meet the power various hydraulic systems source and functional requirements to reduce the energy consumption of the non-working period.

III. SUMMARY OF THE INVENTION

The present invention aims to reduce the conventional hydraulic power source converts mechanical energy into hydraulic energy during the energy loss and achieving energy saving. A hydraulic power source to provide power for the control system and fluid transmission unit, it is converted to mechanical energy with constant pressure and flow of hydraulic power for driving a hydraulic cylinder or a hydraulic motor.

Present invention provides a low idle power consumption hydraulic power source, comprising a hydraulic pump, a motor 2, an accumulator 4, a solenoid valve 5, characterized in that the constant pressure of the hydraulic pump 1 is a variable displacement hydraulic pump, and the addition of the motor speed controller 3, the pressure sensor 6, the displacement sensor 7 and the controller 8; a pressure sensor 6 is mounted in the actual pressure of the first hydraulic line connected to an outlet of the pump 9, the detection system into an electric signal and inputted to the control in 8; displacement sensor 7 is attached to the hydraulic pump 1, the pump is detected swing angle variable mechanism, and the value is converted to an electric signal inputted into the controller 8; accumulator via a first hydraulic line 9, the second hydraulic line 10 is connected to the outlet of the hydraulic pump 1, a solenoid valve 5 controls the accumulator-off between the first hydraulic line 9 and a second hydraulic line 10; a controller 8 according to the actuator control valve 11 , flow requirements 12, 13 is given control of the motor speed command signal W to the motor speed controller 3, and received by the pressure sensor 6 and 7 of the displacement sensor signal, the rotational speed setting value is corrected; speed controller 3 controls the motor speed and power. Actuator control valve ll, 12, 13 for controlling the motion direction and speed of the actuator, the actuator system may be l, 2, or more.

The above low idle power consumption hydraulic power source, characterized in that the hydraulic pump 1 is mechanically controlled variable manual adjustments constant pressure pump, an electrical signal is automatically adjusted or electro-hydraulic proportional constant pressure variable pump.

The above low idle power consumption hydraulic power source, characterized in that the electric motor 2 is an AC induction motors, AC servo motor, or a reluctance motor off.

The above low idle power consumption hydraulic power source, wherein the motor speed can be continuously controller 3 is to control the drive motor speed, the motor control only a few levels of fixed speed controllers, or a soft start device. Low energy turn a hydraulic power source of the present invention is embodied in the major advantage, I, when the hydraulic system at a low pressure, unloading and other non-working cycle, by reducing the rotational speed of the hydraulic pump, the hydraulic pump will be greatly reduced due to the rotation at the rated speed energy loss. II, during the operation of the hydraulic system, by increasing the pump

Speed, can increase the oil flow system and reduce the volume of the selected pump. Ni, since the motor speed controller itself has a function of controlling the motor operation state is constant power, thus making the power source is superimposed wherein the constant power control. IV, by varying the speed of the pump, the pump having a composite function of the pressure and flow control can be achieved to match the flow control multiple actuators. v, and the swing angle by detecting the output pressure of the pump variable mechanism, with the motor speed, the efficiency of the power source can realize optimal control. The present invention may replace conventional hydraulic power source, it is widely used in the hydraulic industry, achieving energy saving. IV BRIEF DESCRIPTION

FIG low idle power consumption i hydraulic power source. among them

a hydraulic pump motor l 2- 3- 4 a motor speed controller accumulator pressure sensor 5- 6- 7- solenoid valve displacement sensor controller 9 8- IO- a first hydraulic line 11 a second hydraulic line, 12, 13 actuator control valve

BRIEF principles and structures of the present invention are described in further detail below in conjunction.

A hydraulic power source low idle power consumption by the hydraulic pump of the present invention is L, the motor 2, the motor speed controller 3, the accumulator 4, switching the solenoid valve 5, the pressure sensor 6, detects the displacement of the pump (swing angle) displacement sensor 7, controller 8, a first hydraulic line 9, the IO second hydraulic line, a control valve actuator ll, 12, 13 and other components. Wherein the hydraulic pump 1 by mechanical constant pressure variable pump or a constant pressure proportional control of the electronic variable pump, characterized in that when the system pressure is lower than the set pressure of the pump, the pump output flow rate corresponding to the maximum displacement . When the system pressure reaches the set value, the pump delivery rate is automatically adapted to the load requirements. 2 is an electric motor prime mover driving the hydraulic pump, electrical energy into mechanical energy. Effect motor speed controller 3 is to control the rotational speed of the motor, but also can serve the purpose of limiting motor torque and power output. 4 is the effect of the accumulator storing a hydraulic oil pressure, hydraulic oil compensating dynamic process flow required insufficient. Solenoid valve 5 controls the operating state of the accumulator is ON or OFF. 6 detects the actual pressure value at the outlet of the hydraulic pump and monitoring the pressure sensor, and converts it into an electric signal to the controller 8. 7 displacement sensor for detecting the swing angle of the hydraulic pump of variable displacement mechanism, and converts the signal into an electric signal is input to the controller 8. 8 is based on the role of the controller operating state of the system, and the information from the pressure sensor 6 provides the displacement sensor 7, the control rotational speed of the motor, and the motor to limit the maximum

Output Power. Actuator control valve ll, 12, 13 to the direction of movement and speed control actuator.

The operation of this power source is: First, according to the movement speed of the load, when the multi-actuator operating conditions, and, by determining the maximum displacement of the pump motor speed based on the speed of each actuator, and this set value 3 to the motor speed controller, when the system pressure is below the set value of the hydraulic pump, according to the characteristics of the pump leakage, pump speed is corrected by the hydraulic system pressure value and the detected displacement. When the system is at maximum pressure, to adapt to varying the pump displacement by simultaneously load and speed the required flow. When the output of the pump power exceeds the set value of the motor power, the controller automatically reduces the speed of the motor

Speed, limiting the hydraulic pump power output. When all of the actuators are not working, pump speed control to a certain minimum value, the system is in low power operating state. Then if a sudden start of the actuator, in order to meet the requirements of the dynamic characteristics, the accumulator can be made by controlling the electromagnetic valve 54 is opened, supplemental traffic.

V. DETAILED DESCRIPTION

Embodiment l:

In the embodiment shown in FIG. 1, the hydraulic pump 1 employs a pilot structure constant pressure variable mechanical control

Pumps, motors, AC induction motor 2, the controller 3 selected motor speed vector control inverter, the accumulator bladder-like structure 4 selected, the solenoid valve 10 selected path 5 of two-way solenoid valves, the pressure sensor 6 selected measurement range is 0-35MPa, and integrated with a preamplifier. Selection of the displacement sensor 7 differential transformer principle, the controller 8 is constituted by a single piece calculator.

Embodiment 2:

Difference between the present embodiment and Embodiment Embodiment 1 Embodiment 1 is mechanically controlled variable constant voltage constant pressure to the pump electro-proportional control variable pump, the motor speed controller 3 selected soft-start, the remainder of the same.

Embodiment 3:

Difference between the present embodiment and the embodiment 1 is the AC induction motor using embodiment 1 was changed to AC servo motor, the rest of the same.

Claims (4)

1. A hydraulic power source low idle power consumption, which contains a hydraulic pump (1), the motor (2), an accumulator (4), solenoid valve (5), characterized in that the hydraulic pump (1) is a constant-voltage type variable displacement hydraulic pump, and the addition of the motor speed controller (3), a pressure sensor (6), a displacement sensor (7) and a controller (8); a pressure sensor (6) installed in the first hydraulic pipe connecting the pump outlet passage (9), the actual pressure detection system, and converted into electrical signals inputted to the controller (8); and a displacement sensor (7) mounted on the hydraulic pump (1), the pump is detected swing angle variable mechanism, value into an electrical signal and inputted to the controller (8); a first hydraulic line (9), a second hydraulic line (10) connected to the hydraulic pump (O outlet of the accumulator through the first a solenoid valve (5) between a hydraulic line (9) and a second hydraulic line (10) on-off control of the accumulator; and a controller (8) the actuator control valve (11), (12), (13) flow requirements, given motor speed control command signal W to the motor speed controller (3) and received by the pressure sensor (6) and a displacement transmission Signal (7), the speed setpoint to be corrected; speed controller (3) controls the speed and power of the motor; actuator control valve (11), (12), (13) for motion control of the actuators direction and speed, the actuator system may be l, 2, or more.

2 electro-hydraulic proportional constant pressure, low idle power consumption of the hydraulic power source according to claim 1, characterized in that the hydraulic pump (1) is mechanically controlled variable manual adjustments constant pressure pump, or an electrical signal is automatically adjusted as.

3, low idle power consumption of the hydraulic power source according to claim 1, characterized in that the electric motor (2) is an AC induction motors, AC servo motor or a switched reluctance motor.

4, according to Claim low idle power consumption of the hydraulic power supply of claim 1, wherein the motor speed controller (3) is a continuous control of the drive motor speed, the motor control only a few levels of fixed speed controllers, or soft start device.