阅读说明：本技术 一种连续比例调节流量的斜轴式柱塞泵变量机构 (Variable mechanism of oblique axis type plunger pump for continuously and proportionally adjusting flow ) 是由 赵斌 白俊 郝云晓 权龙� 王波 于 2019-10-09 设计创作，主要内容包括：本发明公开一种连续比例调节流量的斜轴式柱塞泵变量机构,该机构将传统液压控制的变量机构替换为含有滚珠丝杠的闭环控制变量机构,通过采用滚轴丝杠作为变量机构,采用伺服电机可以提高控制精度和流量控制的准确度。本发明结构更加简单、紧凑,且响应速度快,动作灵敏,利用滚珠丝杠有效的提高了泵的响应速度和精准度,提高了泵的使用价值。(The invention discloses an inclined shaft type plunger pump variable mechanism for continuously and proportionally regulating flow, which replaces a traditional hydraulic control variable mechanism with a closed-loop control variable mechanism containing a ball screw, and can improve the control precision and the flow control accuracy by adopting a servo motor by adopting the ball screw as the variable mechanism. The ball screw pump has the advantages of simpler and more compact structure, high response speed and sensitive action, and effectively improves the response speed and the accuracy of the pump and the use value of the pump by utilizing the ball screw.)

1. A variable displacement mechanism for a continuously proportioned flow slant-axis plunger pump, comprising: valve plate (1), cylinder body (2), center pin (3), pump casing (7), its characterized in that: the device is characterized by also comprising an angular contact ball bearing (4), a ball screw (5), a bearing end cover (6), a ball nut (8), a servo motor (9), a pressure sensor (10), a swing angle sensor (11), a controller (12), a servo driver (13), a coupler (14), a sealing ring (15), a bearing end cover (16) and a bearing (17);

one end of the central shaft penetrates through the central holes of the valve plate and the cylinder body to be mechanically connected with a ball nut, the ball nut is installed on a ball screw, the upper end of the ball screw is fixed on the shell through an angular contact ball bearing and a sealing ring, the lower end of the ball screw is fixed at the bottom end of the shell through a bearing, the upper end of the ball screw and the rotating shaft end of a servo motor are fixedly connected through a coupler, the servo motor is connected with a servo driver, the servo motor drives the ball screw to rotate to drive the ball nut to move up and down along the ball screw, so that the angle of the valve plate and the cylinder; the pressure sensor is arranged at the outlet of the pump and used for detecting the pressure value of the outlet of the pump; the swing angle sensor is arranged on a shell of the pump and connected with the port plate to detect the angle change of the port plate and the cylinder body; the pressure sensor, the swing angle sensor and the servo driver are all connected with the controller, detection signals are all transmitted to the controller and are respectively compared with preset instruction values, then control signals are transmitted to the servo driver, the rotation angle and the rotation speed of the servo motor are respectively changed through the servo driver to realize the control of the variable device, and the plunger pump is ensured to be capable of adjusting output flow and power according to actual working condition requirements;

the controller comprises an A/D signal conversion unit, a D/A signal conversion unit and a CPU, the CPU is used for controlling, calculating, comparing and outputting signals, preset parameters are set in a program of the controller, and the preset parameters comprise preset power and different gears of the servo motor, and different rotating speeds and rotating angles of the servo motor corresponding to different flow rates and swing angles;

the servo driver is integrated with the servo motor, and the rotation of the servo motor is converted into the linear motion of the ball nut;

the encoder is fixed at the rotating shaft end of the motor, transmits signals to the driver by measuring the rotating angle and the rotating speed of the servo motor, and compares the signals with the pulse signals for calculation, so that the running condition of the motor is controlled and detected.

Technical Field

The invention belongs to the field of hydraulic plunger pumps, and particularly relates to an inclined shaft type plunger pump variable mechanism for continuously and proportionally regulating flow.

Background

The inclined shaft type plunger pump has the advantages of good shock resistance, large displacement, strong pollution resistance, high volumetric efficiency, high mechanical efficiency and the like, and is widely applied to engineering machinery with severe working environment and high power.

The prior inclined shaft type plunger pump drives a valve plate by a variable mechanism to change the inclination angle of the valve plate, thereby changing the displacement of the pump. The control modes of the oblique axis type plunger pump are divided into constant pressure control, constant flow control, constant power control and the like according to the control purposes. At present, the mechanical field is mainly a hydraulic control plunger cylinder variable mechanism, and the variable pump is widely applied due to high volumetric efficiency, stable operation and high working pressure. However, the piston is used for pushing the valve plate to realize variable, the structure is complex, the efficiency is low, the sensitivity is low, the high-precision control of the valve plate and the cylinder body is difficult to realize, the pollution to hydraulic oil is sensitive, and the manufacturing cost is relatively high.

Disclosure of Invention

In order to solve the defects of the variable mechanism of the inclined shaft type plunger pump, the invention provides the variable mechanism of the inclined shaft type plunger pump for continuously and proportionally regulating the flow. The ball screw pump has the advantages of simpler and more compact structure, high response speed and sensitive action, and effectively improves the response speed and the accuracy of the pump and the use value of the pump by utilizing the ball screw.

In order to achieve the purpose, the invention adopts the following technical scheme:

a variable displacement mechanism for a continuously proportioned flow slant-axis plunger pump, comprising: the device comprises a valve plate 1, a cylinder body 2, a central shaft 3, an angular contact ball bearing 4, a ball screw 5, a bearing end cover 6, a pump shell 7, a ball nut 8, a servo motor 9, a pressure sensor 10, a swing angle sensor 11, a controller 12, a servo driver 13, a coupler 14, a sealing ring 15, a bearing end cover 16 and a bearing 17;

one end of the central shaft penetrates through the central holes of the valve plate and the cylinder body to be mechanically connected with a ball nut, the ball nut is installed on a ball screw, the upper end of the ball screw is fixed on the shell through an angular contact ball bearing and a sealing ring, the lower end of the ball screw is fixed at the bottom end of the shell through a bearing, the upper end of the ball screw and the rotating shaft end of a servo motor are fixedly connected through a coupler, the servo motor is connected with a servo driver, the servo motor drives the ball screw to rotate to drive the ball nut to move up and down along the ball screw, so that the angle of the valve plate and the cylinder; the pressure sensor is arranged at the outlet of the pump and used for detecting the pressure value of the outlet of the pump; the swing angle sensor is arranged on a shell of the pump and connected with the port plate to detect the angle change of the port plate and the cylinder body; the pressure sensor, the swing angle sensor and the servo driver are all connected with the controller, detection signals are all transmitted to the controller and are respectively compared with preset instruction values, then control signals are transmitted to the servo driver, the rotation angle and the rotation speed of the servo motor are respectively changed through the servo driver to realize the control of the variable device, and the plunger pump is ensured to be capable of adjusting output flow and power according to actual working condition requirements;

the controller comprises an A/D and D/A signal conversion unit and a CPU, the CPU is used for controlling, calculating, comparing and outputting signals, preset parameters are set in a program of the controller, and the preset parameters comprise preset power and different gears of the servo motor, and different rotating speeds and rotating angles of the servo motor corresponding to different flow rates and swing angles;

the servo driver is integrated with the servo motor, and the rotation of the servo motor is converted into the linear motion of the ball nut;

the encoder is fixed at the rotating shaft end of the motor, transmits signals to the driver by measuring the rotating angle and the rotating speed of the servo motor, and compares the signals with the pulse signals for calculation, so that the running condition of the motor is controlled and detected.

Compared with the prior art, the invention has the following advantages:

compared with the prior art, the invention adopts the roller screw as the variable mechanism and adopts the servo motor to improve the control precision and the flow control accuracy; compared with a piston type variable mechanism, the pump has the advantages of simpler and more compact structure, high response speed and sensitive action, and the response speed and the accuracy of the pump are effectively improved by utilizing the ball screw, so that the use value of the pump is improved.

Drawings

FIG. 1 is a schematic structural diagram of a variable displacement mechanism of an oblique axis type plunger pump according to the present invention;

FIG. 2 is a schematic diagram of the operation of the servo driver of the present invention;

fig. 3 is a schematic diagram of the controller according to the present invention.

In the figure: the device comprises a flow distribution plate 1, a cylinder body 2, a central shaft 3, an angular contact ball bearing 4, a ball screw 5, a bearing end cover 6, a pump shell 7, a ball nut 8, a servo motor 9, a pressure sensor 10, a swing angle sensor 11, a controller 12, a servo driver 13, a coupler 14, a sealing ring 15, a bearing end cover 16 and a bearing 17.

Detailed Description

The technical solutions in the embodiments of the present invention are further described in detail below.

A variable displacement mechanism for a continuously proportional variable displacement pump, as shown in fig. 1-3, comprising: the device comprises a valve plate 1, a cylinder body 2, a central shaft 3, an angular contact ball bearing 4, a ball screw 5, a bearing end cover 6, a pump shell 7, a ball nut 8, a servo motor 9, a pressure sensor 10, a swing angle sensor 11, a controller 12, a servo driver 13, a coupler 14, a sealing ring 15, a bearing end cover 16 and a bearing 17.

Center pin one end pass the centre bore of thrust plate and cylinder body and ball nut mechanical connection, ball nut installs on ball, ball upper end is fixed on the casing through angular contact ball bearing and sealing washer, ball's lower extreme passes through the bearing to be fixed in the casing bottom, the shaft coupling is connected the upper end of ball and servo motor's pivot end fixedly, servo motor is connected with servo driver, servo motor drive ball is rotatory, it reciprocates along ball to drive ball nut, thereby change the angle of thrust plate and cylinder body, change the discharge capacity of pump. The pressure sensor is arranged at the outlet of the pump and used for detecting the pressure value of the outlet of the pump; the swing angle sensor is arranged on a shell of the pump and connected with the port plate to detect the angle change of the port plate and the cylinder body. The pressure sensor, the swing angle sensor and the servo driver are all connected with the controller, detection signals are all transmitted to the controller and are respectively compared with preset instruction values, then control signals are transmitted to the servo driver, the rotation angle and the rotation speed of the servo motor are respectively changed through the servo driver to realize control over the variable device, the plunger pump can be guaranteed to adjust output flow and power according to actual working condition requirements, and the plunger pump can be used as a constant pressure pump and a variable displacement pump.

The controller comprises an A/D signal converter, a D/A signal converter and a CPU, the CPU is used for controlling, calculating, comparing and outputting signals, preset parameters are set in a program of the controller, and the preset parameters comprise preset power and different gears of the servo motor, and different rotating speeds and rotating angles of the servo motor corresponding to different flow rates and swing angles.

The servo driver is integrated with the servo motor, and the working principle of the servo driver is as follows: the method comprises the steps that a current, speed and position three-closed-loop control algorithm based on vector control is adopted, an input pulse signal is subjected to complex calculation, and then an alternating current servo motor is driven through phase voltage control PWM; the servo driver determines the rotation speed through the frequency of an externally input pulse signal, and determines the rotation angle through the number of input pulses. The servo driver and the servo motor form a complete servo system. By converting the rotation of the servo motor into linear motion of the ball nut. The ball nut moves a distance of one thread pitch for each revolution of the servo motor.

The encoder is fixed at the rotating shaft end of the motor, signals are transmitted to the driver by measuring the rotating angle and the rotating speed of the servo motor, and the signals are compared with the pulse signals for calculation, so that the running condition of the motor is controlled and detected.