阅读说明：本技术 一种轴向柱塞泵内部压力无线测试系统 (Wireless test system for internal pressure of axial plunger pump ) 是由 王君 武兵 周晓磊 林健 熊晓燕 牛蔺楷 于 2020-06-11 设计创作，主要内容包括：本发明公开一种轴向柱塞泵内部压力无线监测系统,通过在柱塞泵缸体安装微型压力传感器,将压力传感器信通过导线连接至数据采集装置,通过无线方式将数据传输给接收端。系统上电后,数据采集装置处于休眠状态,当接收到上位机发来的开始数据采集信号时,采集端开始进行数据采集,并将数据传输至无线数据接收装置,最终传输至上位机。数据采集结束,可以通过发送数据采集结束命令终止数据采集。该系统采样精度高,使用寿命长,对柱塞泵影响小、可以实现柱塞泵内部压力的实时监测,可为柱塞泵内部压力分析研究提供有效数据。(The invention discloses a wireless monitoring system for internal pressure of an axial plunger pump. After the system is powered on, the data acquisition device is in a dormant state, when a data acquisition starting signal sent by an upper computer is received, the acquisition end starts to acquire data, transmits the data to the wireless data receiving device and finally transmits the data to the upper computer. And when the data acquisition is finished, the data acquisition can be terminated by sending a data acquisition finishing command. The system has the advantages of high sampling precision, long service life, small influence on the plunger pump, realization of real-time monitoring of the internal pressure of the plunger pump and capability of providing effective data for analysis and research of the internal pressure of the plunger pump.)

1. The utility model provides a wireless test system of axial plunger pump internal pressure which characterized in that: the device comprises a micro pressure sensor (1), a data processing device (2) connected with the micro pressure sensor, a wireless data transmitting device (3), a wireless power supply device (4), an electric energy receiving device (5) corresponding to the wireless power supply device, a wireless data receiving device (6), an upper computer (7) connected with the wireless data receiving device, a data acquisition circuit board protective shell and a component (8) thereof, and a data receiving circuit board protective shell and a component (9) thereof;

the miniature pressure sensor is fixed on the side surface of a cylinder body of the plunger pump and is contacted with hydraulic oil in a plunger cavity (11) through a through hole, and a signal wire of the pressure sensor is connected with a data processing device (2) fixed at the shaft end through a small wire hole (12) on the cylinder body and a small wire hole (14) on the rotating shaft;

the pressure acquisition device includes: STM32, an amplifying chip and a peripheral circuit, a filter circuit, an analog-to-digital conversion chip and a peripheral circuit, a TF card and a peripheral circuit and a printed circuit board, wherein the circuits and the chips are welded on the printed circuit board;

the wireless data transmitting apparatus includes: the chip comprises a CC2540 chip, peripheral circuits, an on-chip antenna, an I/O interface and a printed circuit board, wherein the circuits and the chip are welded on the printed circuit board;

the wireless power receiving apparatus includes: the alternating current-direct current conversion circuit comprises a copper coil, an alternating current-direct current conversion circuit and a printed circuit board, wherein related components of the alternating current-direct current conversion circuit are welded on the printed circuit board, and the copper coil is fixed on the back of the printed circuit board through AB glue;

data acquisition device protective housing and its subassembly include: the protective device comprises a protective shell (24), a protective cover (25), a fixing stud (20), a fixing hole (26) and a screw (27); the internal circuit board is combined through the fixing studs and then fixed on the protective shell through screws; the protective shell is connected with a threaded hole (36) on the rotating shaft through a screw, so that the protective shell is fixed on the rotating shaft;

the data wireless receiving apparatus includes: the device comprises a CC2540 chip, a peripheral circuit, an on-chip antenna, a USB interface and a printed circuit board; the circuit, the module and the interface are integrated on the printed circuit board; the acquisition device is connected with an external upper computer (22) through a USB data line (23);

the wireless power supply device includes: the direct current-alternating current conversion circuit, the copper coil and the printed circuit board; the circuit related elements are welded on the printed circuit board, and the copper coil is adhered on the printed circuit board through the AB glue;

the data receiving device protective case includes: protective housing (28), sealed glue (29), fixed orifices (30), screw (31) and wiring hole (33), protective housing passes through screw, behind the plunger pump screw hole (35) of covering and with protective housing shape like the through-hole (36) that adapts to, realizes that protective housing is fixed on back lid (32), and inside printed circuit board passes through double-screw bolt (34) to be fixed in the middle of the shell, directly pours into sealed glue into the protective housing and realizes inside printed circuit board and external isolation.

2. The system for wirelessly testing the internal pressure of the axial plunger pump according to claim 1, wherein: the upper computer is positioned outside the plunger pump, and a lead is led out through a wiring hole on the rear cover and is connected with a wireless data receiving device fixed inside the rear cover of the plunger pump; the upper computer can be used for a worker to check after receiving the pressure signal, and the worker sends a data acquisition starting command, a sampling rate, a sampling length and a collection stopping command to the wireless acquisition device in the plunger pump through the upper computer to realize wireless data transmission and command interaction.

3. The system for wirelessly testing the internal pressure of the axial plunger pump according to claim 1, wherein: the miniature pressure sensor is fixed on the side surface of the cylinder body of the plunger pump, is close to the oil outlet, the position of the fixed small hole (10) of the miniature pressure sensor does not influence the normal operation of the plunger pump, and is always contacted with hydraulic oil in the plunger cavity; the sensor wire is led out through the small wiring holes on the cylinder body and the rotating shaft and is connected to the data acquisition device at the shaft end; the position of a wiring small hole (12) on the cylinder body is positioned on an entity between the two plunger cavities, the wiring small hole penetrates from the side surface of the cylinder body to the center of the cylinder body, and the size of the wiring small hole is as small as possible under the condition that a wire is ensured to pass through; the small wiring holes (14) on the rotating shaft are L-shaped, two sections of holes are respectively positioned at the shaft end of the rotating shaft along the axial direction and the side surface of the rotating shaft along the radial direction, and the depth of the axial hole corresponds to the position of the small wiring holes on the cylinder body; the size of the wiring small hole of the rotating shaft is matched with the thickness of the sensor wire.

4. The system for wirelessly testing the internal pressure of the axial plunger pump according to claim 1, wherein: the data acquisition device, the wireless data transmitting device, the wireless energy receiving device and the protective shell thereof are fixed at the shaft end of the rotating shaft through screws and rotate along with the rotating shaft; the wireless data receiving device, the wireless power supply device and the protective shell thereof are fixed on the rear cover through screws and through holes (36) on the rear cover and are kept static; the two protective shells adopt nonmetal devices which can be penetrated by electromagnetic waves, and the strength of the two protective shells can bear the hydraulic oil pressure and the rotating impact of the rotating shaft between the plunger pump shell and the plunger pump cylinder body; the two protective cases are positioned on the same axis, and the distance between the two protective cases is matched with the wireless power supply distance and the size of the inner space of the plunger pump.

5. The system for wirelessly testing the internal pressure of the axial plunger pump according to claim 1, wherein: the data acquisition device protective shell consists of a protective shell, a protective cover, 4 screws and 2 studs; 2 studs are matched with through holes on printed circuit boards of the acquisition device, the wireless energy receiving device and the wireless data transmitting device, and the devices are fixed in the protective shell by matching with 2 screws; the other 2 screws are matched with the threaded holes on the rotating shaft to fix the shell at the shaft end of the rotating shaft.

6. The system for wirelessly testing the internal pressure of the axial plunger pump according to claim 1, wherein: the data receiving device protective shell consists of a protective shell, 2 screws and 2 studs; the flange structure of the protective shell is fixed on the rear cover through screws, and is injected into a gap through sealant to realize sealing; through filling sealed glue to protective housing inside, realize inside printed circuit board and the isolation of hydraulic oil.

Technical Field

The invention belongs to the technical field of wireless testing of internal pressure of a hydraulic axial plunger pump. In particular to an axial plunger pump which can be provided with a pressure sensor.

Background

The hydraulic axial plunger pump is a main power source of a hydraulic system and is widely applied to industrial occasions such as aerospace, engineering machinery and the like. The stability of the output pressure of the plunger pump is directly related to the stability of the whole hydraulic system. The method has great significance for accurately testing the pressure change inside the plunger pump, researching the pressure pulsation forming mechanism of the plunger pump and reducing the vibration and noise of the plunger pump.

In the operation process of the plunger pump, the plunger pump realizes oil suction and discharge through reciprocating motion and rotating motion around a shaft in the plunger cavity. The pressure inside the plunger chamber is to be tested, and the traditional testing method of the wired connection sensor cannot be used. The existing plunger cavity pressure testing method is mostly carried out by using a mercury slip ring and an FM frequency modulation transmitter. However, due to the inherent physical characteristics of the mercury slip ring and the FM transmitter, a large amount of noise is generated in the signal transmission process, the signal to noise ratio is low, and the accuracy of the acquired data is not high.

Disclosure of Invention

The invention provides a method for testing the internal pressure of a plunger pump based on a wireless sensor, aiming at the problems and the defects of the existing method for testing the internal pressure of the plunger pump. The testing of the internal pressure of the plunger pump is realized through the miniature pressure sensor, the protective shell, the data acquisition module, the wireless power supply module and the wireless data sending and receiving module.

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

a wireless test system for internal pressure of an axial plunger pump comprises a miniature pressure sensor 1, a pressure acquisition device 2 connected with the pressure sensor, a wireless data transmitting device 3, a wireless power supply device 4, an electric energy receiving device 5 corresponding to the wireless power supply device, a wireless data receiving device 6, an upper computer 7 connected with the wireless data receiving device, a data acquisition circuit board protective shell and a data receiving circuit board protective shell assembly 8, and a data receiving circuit board protective shell assembly 9;

the miniature pressure sensor is fixed on the side surface of a plunger cavity 11 of the cylinder body through a sensor fixing hole 10, a lead connected with the miniature sensor is connected with a data processing device 2 fixed at the shaft end through a small wiring hole 12 on the cylinder body and a small wiring hole 14 on a rotating shaft 13, the pressure sensor leads out 4 leads 15 to be connected with a printed circuit board of an acquisition device, wherein 2 leads are signal lines, one lead is a power supply line, and the other lead is a ground line;

the pressure acquisition device 2 includes: STM32, an amplifying chip and a peripheral circuit, a filter circuit, an analog-to-digital conversion chip and a peripheral circuit, a TF card and a peripheral circuit and a printed circuit board, wherein the circuits and the chips are welded on the printed circuit board;

the data wireless transmission module 16 includes: the CC2540 chip, a peripheral circuit, an on-chip antenna, an I/O interface and a printed circuit board are fixedly connected with the printed circuit board through a fixing stud 17 by adopting the printed circuit board antenna, and the transmission of signals and power supply is realized through 4 pins and corresponding female seats;

the wireless power receiving device 18 includes: alternating current-direct current conversion circuit, printed circuit board and copper coil. The wireless electric energy receiving device is fixedly connected with the protective shell through a fixing stud 20, and power supply transmission is realized through 2 pin headers and corresponding female seats;

the wireless data receiving apparatus 21 includes: the device comprises a CC2540 chip, a peripheral circuit, an on-chip antenna, a USB interface and a printed circuit board; the circuit, the module and the interface are integrated on the printed circuit board; the upper computer 22 is positioned beside the plunger pump and is connected with the data receiving device through a USB data line 23 to display pressure information in real time;

the wireless power supply device 19 includes: a DC-AC conversion circuit, a copper coil and a printed circuit board. The circuit related elements and the coil are fixed on the printed circuit board and fixed on the protective shell through a stud 34;

the data acquisition circuit board protective housing includes: a protective case 24, a protective cover 25, a fixing hole 26, and a screw 27; the protective shell is connected with the threaded hole 36 on the rotating shaft through a screw, so that the protective shell is fixed on the rotating shaft;

the data receiving device protective case includes: the protective shell 28, the sealant 29, the fixing hole 30, the screw 31 and the wiring hole 33; the protective shell realizes the fixation of the protective shell on the back cover 32 through a screw, a threaded hole 35 on the back cover of the plunger pump and a through hole 36 which is matched with the shape of the protective shell;

the data acquisition device, the wireless data transmitting device and the wireless energy receiving device are fixed in the data acquisition circuit board protective shell through fixing studs; the acquisition circuit protection shell is fixed at the shaft end of the rotating shaft 13 through two screws and rotates along with the shaft; the wireless power supply device and the wireless data receiving device are fixed in the protective shell of the data receiving device through screws; the data receiving device protective housing is fixed to the rear cover 32 by screws and is fixed; two protective housings all are non-metallic material, can guarantee the transmission of electromagnetic wave signal, avoid the circuit board to receive the erosion of hydraulic oil.

The invention has the following beneficial effects:

1. through introducing wireless data transmission and wireless power supply module, can gather the cylinder body internal pressure of high-speed rotation.

2. The wireless data transmission mode improves the signal-to-noise ratio of signals, and the wireless power supply mode increases the running time of the system. The running time and the accuracy of the system are improved.

3. The wiring mode of the miniature pressure sensor and the arrangement of the acquisition device do not influence the normal operation of the plunger pump. The accuracy of the acquired data is ensured.

4. The test system is convenient to install, has small structural change to the plunger pump, and is convenient to implement and apply.

Drawings

FIG. 1 is a three-dimensional view of a plunger pump profile;

FIG. 2 is a system overview;

FIG. 3 is a three-dimensional view of the acquisition device;

FIG. 4 is an exploded view of the collection device;

FIG. 5 is a three-dimensional view of a receiving device;

FIG. 6 is an exploded view of the receiver;

FIG. 7 is a three-dimensional view of the cylinder;

FIG. 8 is a three-dimensional view of the cylinder;

fig. 9 is a three-dimensional view of the back cover.

In the figure: 1-a miniature pressure sensor; 2-a pressure data processing device; 3-a wireless data transmitting device; 4-a wireless power supply; 5-a wireless power receiving device; 6-wireless data receiving means; 7-an upper computer; 8-data acquisition circuit board protective housing and its assembly; 9-data receiving circuit board protective housing and its assembly; 10-a fixed base; 11-plunger pump cylinder; 12-routing aperture; 13-a rotating shaft; 14-routing aperture; 15-a wire; 16-a wireless transmission module; 17-a fixing stud; 18-a radio energy receiving device; 19-a copper coil; 20-fixing studs; 21-a wireless data receiving device; 22-an upper computer; 23-a USB data line; 24-a protective housing; 25-a protective cover; 26-a fixation hole; 27-a screw; 28-a protective housing; 29-sealing glue; 30-a fixing hole; 31-a screw; 32-rear cover; 33-wiring holes; 34-a bolt; 35-a threaded hole; 36-through hole.

Detailed Description

The detailed technical scheme of the invention is described in the following with the accompanying drawings:

a system for wirelessly testing internal pressure of an axial plunger pump comprises: the system comprises a micro pressure sensor, an acquisition device connected with the pressure sensor, a wireless data transmitting device connected with the acquisition device, a wireless energy receiving device, a wireless power supply device, a wireless data receiving device, an upper computer connected with the wireless data receiving device, an acquisition device protective shell and a receiving device protective shell;

specifically, a micro pressure sensor is arranged on a transition area of a plunger pump cylinder body. And leading out a signal wire of the pressure sensor through a wiring small hole 12 of the cylinder body and a small hole 14 in the center of the rotating shaft, and transmitting the signal wire to a data acquisition and transmission node fixed at the shaft end. The data acquisition sending node wirelessly transmits acquired data to a wireless receiving device fixed on a rear cover of the plunger pump, and the acquired data are transmitted to an upper computer through a data line.

In order to accurately acquire the internal pressure of the plunger pump under the condition of not influencing the operation of the plunger pump, the mounting position of the miniature pressure sensor is arranged on the side surface of the cylinder body and close to the transition area of the oil outlet. In order to ensure the transmission of pressure signals, holes are respectively drilled between the two plunger cavities 11 of the cylinder body, the side surface of the rotating shaft and the axial center. The normal operation of the plunger pump and the transmission of signals are not affected.

In order to guarantee the collection and the wireless receiving and dispatching of data, at pivot axle head installation data acquisition device 2, data acquisition device includes: STM32, an amplifying chip and peripheral circuit, a filter circuit, an analog-to-digital conversion chip and peripheral circuit, a TF card, related peripheral circuit and a printed circuit board, wherein the circuits and the chips are welded on the printed circuit board; the analog signals collected by the pressure sensor are transmitted to the collecting device through the conducting wire. The signal is amplified, filtered, analog-to-digital converted and finally transmitted out through a wireless transmitting device. The wireless data transmitting apparatus includes: the antenna comprises an on-chip antenna, a CC2540 radio frequency chip, a related peripheral circuit and a printed circuit board, wherein the circuits and the chip are welded on the printed circuit board; the wireless power receiving apparatus includes: the circuit comprises a copper coil, a related circuit and a printed circuit board, wherein related elements of the circuit are welded on the printed circuit board, and the copper coil is fixed on the printed circuit board through AB glue. Three printed circuit boards are fixed through the studs and the holes designed on the circuit boards

To ensure that the internal circuit boards of the data acquisition device are not attacked by the hydraulic oil, the acquisition device is secured in a protective housing 24. In order to ensure the fixation of the shell at the shaft end, 2 threaded holes 34 are arranged at the corresponding position of the shaft end, 2 holes with matched sizes are arranged at the corresponding position of the protective shell, and the protective shell is fixed at the shaft end of the rotating shaft through screws. The protective shell is made of non-metal materials, so that transmission of wireless signals is guaranteed.

In order to ensure that the position of the data acquisition device is fixed in the protective shell, 2 holes are arranged on the protective cover of the protective shell, and the size of each hole is matched with the size of the stud for fixing the printed circuit board. When the data acquisition device is installed, the protective shell is firstly fixed at the shaft end through the screw, then the data acquisition device is fixed at the shell protective cover through the screw, and finally the shell protective cover is fixed with the protective shell through the screw thread, and the data acquisition device is sealed in the protective shell. And coating sealant in the gaps of the structural joints to ensure good sealing.

In order to ensure the normal receiving of wireless data and the supplying of wireless energy, a wireless data receiving device and a wireless power supply device are sealed inside the plunger pump. The plunger pump rear cover is provided with a through hole, and the protective shell is embedded into the through hole 36 and fixed on the rear cover through screws. The wireless power supply coil is tightly attached to the rear cover of the protective shell and keeps a short distance with the wireless power receiving coil, and meanwhile, the two coils ensure a concentric shaft, so that wireless power supply can be smoothly carried out in the running process of the plunger pump. A wiring hole is formed in the outer portion of the shell, a wire is connected with an upper computer through the wiring hole to transmit data out, and meanwhile a power line supplies power to equipment through the hole.