A photoelectric detection sensor for a hydraulic automatic exhaust valve

Abstract

The present invention belongs to the field of detection, and specifically relates to a novel photoelectric detection sensor for a hydraulic automatic exhaust valve. The sensor comprises a photoelectric detection circuit board, a ring-shaped detection component, a light source, and a photoelectric receiver; the ring-shaped detection component comprises a ring-shaped detection structure, a transmitting lens, and a receiving lens.

Description

Technical Field

[0001] The invention belongs to the field of detection, and in particular relates to a photoelectric detection sensor for a hydraulic automatic exhaust valve. Background Art

[0002] Gas in hydraulic system piping accumulates at the top of the hydraulic tank as the oil flows. This gas forms cavitation holes, which remain in the tank and cannot be exhausted. During hydraulic system operation, cavitation can lead to a series of negative effects, such as increased oil temperature, increased pump wear, increased vibration, and ultimately, cavitation. These can severely compromise the proper functioning of the hydraulic system. Furthermore, the continuous incorporation of air into the hydraulic system is a normal and unavoidable phenomenon. This gas can only be exhausted and decompressed via the vent valve installed at the top of the tank.

[0003] Currently, traditional oil exhaust valves are roughly divided into two categories: manual exhaust valves and mechanical exhaust valves. Manual exhaust valves have a simple structure and high reliability. However, they do not have the function of detecting exhaust pressure, and the exhaust effect is not guaranteed. The working principle of traditional mechanical automatic exhaust valves uses a valve core and spring structure. The valve core is pressed against the sealing ring by the spring, thus preventing gas from being discharged through small holes or gaps. When the gas increases, the pressure in the oil tank increases, overcoming the spring force and moving the valve core, allowing the gas to freely pass through the small holes or gaps to be discharged to the outside. This exhaust method relies on the pressure conditions in the hydraulic oil tank. On the one hand, it is difficult to control the amount of oil leakage during exhaust. On the other hand, it is also difficult to control the exhaust effect, which poses a significant safety hazard to the aircraft hydraulic system. Summary of the Invention

[0004] The purpose of the present invention is to provide a photoelectric detection sensor for a hydraulic automatic exhaust valve, which controls the operation of the solenoid valve to exhaust gas and outputs the detected gas alarm signal through an interface circuit. At the same time, the photoelectric detection sensor can respond to the control of an external enable signal, has a closer cross-linking relationship with the system, and has higher control reliability.

[0005] The present invention provides a photoelectric detection sensor for a hydraulic automatic exhaust valve, comprising: a photoelectric detection circuit board, a ring-shaped detection component, a light source, and a photoelectric receiver; the ring-shaped detection component comprises a ring-shaped detection structure, a transmitting lens, and a receiving lens;

[0006] The annular detection assembly is installed in the hydraulic cavity of the automatic exhaust valve, and the photoelectric detection circuit board is installed in the mounting cavity of the automatic exhaust valve. The annular detection structure is the structural main body of the annular detection assembly. The annular detection cavity inside it is a stepped hole structure, and the stepped surface of the stepped hole is an inclined surface. Two transparent mounting holes are provided on the stepped surface along the radial direction of the annular detection assembly. A light source is installed in one mounting hole, and the light source and the annular detection cavity are isolated by a transmitting lens. A photoelectric receiver is installed in the other mounting hole, and the photoelectric receiver and the annular detection cavity are isolated by a receiving lens.

[0007] When the photoelectric detection sensor is working, the light emitted by the light source passes through the transmitting lens and enters the receiving lens in a straight line, and the photoelectric receiver receives the intensity of the transmitted light; the photoelectric detection circuit board is electrically connected to the light source and the photoelectric receiver.

[0008] The transmitting lens and the receiving lens are respectively glued into two mounting holes in a straight line symmetrical position to form a detection light path.

[0009] The transmitting lens forms an angle of 45 degrees with the oil level in the annular detection cavity, and the receiving lens forms an angle of 135 degrees with the oil level in the annular detection cavity.

[0010] The photoelectric detection circuit board includes: power supply step-down circuit, light source driving circuit, photoelectric conversion circuit, photoelectric threshold comparison circuit, exhaust trigger judgment circuit, solenoid valve driving circuit, exhaust enabling circuit;

[0011] The power supply step-down circuit is used to reduce the voltage for use by the entire photoelectric detection circuit board;

[0012] The light source driving circuit is used to provide a constant driving current to the light source;

[0013] The light intensity information output by the photoelectric receiver passes through the photoelectric conversion circuit, the photoelectric threshold comparison circuit, the exhaust trigger judgment circuit, and the solenoid valve drive circuit in sequence, and is finally output to the solenoid valve drive end, and outputs high and low levels to the outside in the form of exhaust alarm prompts. When the gas content in the annular detection cavity is too high and exhaust is required, the exhaust alarm signal output is high. When the gas content in the annular detection cavity is not high and exhaust is not required, the exhaust alarm signal output is low.

[0014] An anti-shake circuit is provided between the photoelectric threshold comparison circuit and the exhaust trigger judgment circuit.

[0015] The solenoid valve drive circuit provides a maximum drive capability of +32V, 2A for the external solenoid valve coil.

[0016] The solenoid valve drive circuit specifically controls the action of the solenoid valve according to the external input exhaust enable signal. The exhaust enable signal and the exhaust alarm signal form an "AND" logical control relationship for the exhaust control; if the exhaust enable signal enable logic level is low, the solenoid valve does not act, and if the enable logic level is high, the solenoid valve is allowed to make corresponding conduction according to the liquid level judgment result. The photoelectric detection circuit board also outputs the exhaust alarm status according to the result of the liquid level judgment.

[0017] The voltage drop range is from +18V to +32V to +5.9±0.1V.

[0018] The present invention proposes a photoelectric detection sensor for an automatic exhaust valve. This sensor, which employs the principle of photoelectric liquid level recognition, generates an exhaust alarm signal by identifying the medium (the ratio of air to oil content) entering the annular detection structure cavity, and provides a drive path for the exhaust of the solenoid valve. Unlike traditional mechanical exhaust methods, the exhaust alarm output of the photoelectric detection sensor is independent of the liquid pressure. To enhance the reliability of system identification and eliminate interference with the detection signal caused by fluctuations at the gas-liquid interface, bubbles, and lens attachment to the wall, an anti-shake circuit is specifically incorporated into the circuit of the photoelectric detection sensor to improve the stability of the detection effect, thereby reducing the possibility of oil leakage from the hydraulic oil tank through the exhaust valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the composition diagram of the photoelectric detection sensor for the automatic exhaust valve;

[0020] Figure 2 This is the composition diagram of the photoelectric detection sensor for the automatic exhaust valve;

[0021] Figure 3 It is a diagram of the ring detection structure;

[0022] Figure 4 This is the block diagram of the photoelectric detection circuit board. DETAILED DESCRIPTION

[0023] The present invention is described in further detail below.

[0024] The present invention provides a photoelectric detection sensor for a hydraulic automatic exhaust valve. Figure 1-2 , including: a photoelectric detection circuit board 1, a ring detection component, a light source 2, and a photoelectric receiver 3; the ring detection component includes a ring detection structure 4, a transmitting lens 5, and a receiving lens 6.

[0025] The photoelectric detection sensor is installed inside the hydraulic automatic exhaust valve cavity. Its most important annular detection component and photoelectric detection circuit board are installed inside the hydraulic cavity and installation cavity of the exhaust valve respectively. That is, the annular detection structure is fixedly installed in the hydraulic cavity of the exhaust valve to form an annular detection cavity that senses the liquid level. The annular detection component is installed in the middle of the hydraulic cavity of the automatic exhaust valve as part of the hydraulic cavity. The annular detection structure ( Figure 3 ) is the structural main body of the annular detection assembly. It has two transparent mounting holes 7 extending into the annular detection cavity along its radial direction. One mounting hole houses the light source 2 and transmitting lens 5, while the other houses the photoelectric receiver 3 and receiving lens 6. The transmitting lens forms a 45-degree angle with the oil level in the hydraulic chamber, while the receiving lens forms a 135-degree angle with the oil level in the hydraulic chamber. The transmitting lens and receiving lens are glued into two linearly symmetrical mounting holes and sealed from the annular detection cavity. The two mounting holes 7 in the annular detection cavity are symmetrically aligned, allowing light emitted by the light source to pass straight through to the photoelectric receiver. The photoelectric detection circuit board is mounted and fixed within the mounting cavity of the automatic exhaust valve. When the photoelectric detection sensor is operating, light emitted by the light source passes through the transmitting lens and enters the receiving lens in a straight line. The photoelectric receiver detects the intensity of the transmitted light. The photoelectric detection circuit board is electrically connected to the light source and the photoelectric receiver. The photoelectric detection circuit board not only provides a constant driving current to the light source but also senses changes in the gas-liquid content in the annular detection cavity by measuring the photocurrent of the photoelectric receiver. After the photoelectric detection circuit board makes its judgment, the solenoid valve drive circuit activates and deactivates the exhaust. The circuit board is also responsible for determining the exhaust enable signal input from the external interface. If the exhaust enable logic level is low, the solenoid valve is not permitted to operate. If the exhaust enable logic level is high, the solenoid valve is permitted to operate according to the liquid level judgment. The photoelectric detection circuit board also outputs an exhaust alarm based on the liquid level judgment. When the gas content in the annular detection chamber is high and the liquid level is too low, requiring exhaust, the exhaust alarm signal is high. When the gas content in the annular detection chamber is low and the liquid level is too high, requiring exhaust, the exhaust alarm signal is low.

[0026] The photoelectric detection circuit board is installed in the exhaust valve mounting cavity and is electrically connected to the light source and photoelectric receiver. The conditioning circuit on the photoelectric detection circuit board detects changes in light intensity within the annular detection cavity. Strong light indicates low oil level in the annular detection cavity, while weak light indicates high oil level. When the oil level is low, the photoelectric detection circuit board activates exhaust, and when it is low, it deactivates exhaust.

[0027] The photoelectric detection circuit board 1 is installed in a mounting cavity independent of the annular detection structure. Figure 4, mainly including: power supply step-down circuit 11, light source driving circuit 12, photoelectric conversion circuit 13, photoelectric threshold comparison circuit 14, anti-shake circuit 18, exhaust trigger judgment circuit 15, solenoid valve driving circuit 16, exhaust enabling circuit 17.

[0028] The power supply step-down circuit steps down the voltage of +18V to +32V to +5.9±0.1V for use by the entire photoelectric detection circuit board.

[0029] The light source driving circuit is used to provide a constant driving current to the light source.

[0030] The photocurrent output by the photoelectric receiver is converted into a photovoltage signal through a photoelectric conversion circuit.

[0031] The threshold value of the photoelectric threshold comparison circuit is the corresponding value for preliminary judgment of the gas-liquid content.

[0032] Considering that the gas-liquid interface in the annular detection cavity may experience fluctuations, bubbles, and oil lenses adhering to the wall, which may lead to unstable detection and recognition effects, an anti-shake circuit is designed between the photoelectric threshold comparison circuit and the exhaust trigger judgment circuit. The exhaust trigger judgment circuit is the corresponding value of the detection medium after eliminating the influence of the fluid state.

[0033] The light intensity information output by the photoelectric receiver passes through the photoelectric conversion circuit, photoelectric threshold comparison circuit, anti-shake circuit, exhaust trigger judgment circuit, and solenoid valve drive circuit in sequence, and is finally output to the solenoid valve drive end, and outputs high and low levels to the outside in the form of exhaust alarm prompts. When the gas content in the annular detection cavity is too high and exhaust is required, the exhaust alarm signal output is high. When the gas content in the annular detection cavity is not high and exhaust is not required, the exhaust alarm signal output is low.

[0034] The solenoid valve drive circuit can provide a maximum driving capability of +32V, 2A for the external solenoid valve coil.

[0035] The solenoid valve drive circuit specifically controls the action of the solenoid valve according to the external input exhaust enable signal. If the exhaust enable signal enable logic level is low, the solenoid valve does not act. If the enable logic level is high, the solenoid valve is allowed to make corresponding conduction according to the liquid level judgment result. The photoelectric detection circuit board also outputs the exhaust alarm status according to the result of the liquid level judgment.

[0036] The working principle of the present invention is as follows: a photoelectric detection sensor installed inside the exhaust valve detects and identifies the oil and gas liquid level within the annular detection structure 4. A light source 3 fixedly mounted within the mounting hole 7 of the annular detection structure 4 generates light through a transmitting lens 5. When the medium in the detection chamber is air, the light is transmitted through a receiving lens 6 and received by a photoelectric receiver 3, which then transmits it to the photoelectric detection sensor module circuit board 3. When the medium in the detection chamber is oil, the light generated by the light source 2 is blocked by the oil through the transmitting lens 5, and no or very little light is received by the photoelectric receiver 3 behind the receiving lens 6. Simultaneously, a photocurrent is transmitted to the photoelectric detection circuit board 1. The photoelectric detection circuit board 1 identifies the liquid level based on the difference in light intensity received by the photoelectric receiver 3 in different media, and then outputs an exhaust alarm signal. Simultaneously, the exhaust enable signal obtained by the input controls the on / off control of the solenoid valve drive circuit.

[0037] The electrical design principle of the present invention is as follows: The photoelectric detection circuit board 1 primarily comprises a power supply voltage-step-down circuit, a light source driver circuit, a photoelectric conversion circuit, a photoelectric threshold comparison circuit, an anti-shake circuit, an exhaust trigger determination circuit, and a solenoid valve driver circuit. The power supply voltage-step-down circuit is responsible for stepping down the +18-32V input voltage to +5.9±0.1V; the light source driver circuit is responsible for providing a constant drive current to the light source assembly; the photoelectric conversion circuit primarily converts the photocurrent of the photoreceiver 3 into a voltage signal for subsequent circuitry to filter and perform threshold comparison. The photoelectric threshold comparison circuit, anti-shake circuit, and exhaust trigger determination circuit collectively detect gas-liquid content by determining the photovoltage threshold level. Their detection performance represents the present invention's ability to distinguish gas-liquid states. Taking into account the fluctuations, bubbles, oil adhesion and wall hanging phenomena that may occur at the gas-liquid interface in the detection chamber, a delayed anti-shake circuit processing is added; the anti-shake circuit can eliminate transient spikes and glitches in the gas-liquid signal, and ensure the effectiveness of gas-liquid detection by judging the continuous stability of the signal within a certain period of time; the photoelectric detection circuit board 1 can be electrically connected to the exhaust solenoid valve through the solenoid valve drive circuit, and provide a certain output power to the exhaust valve to control the opening and closing of the exhaust; the solenoid valve drive circuit also determines whether the exhaust action can be performed at present based on the exhaust enable signal, and the exhaust enable signal and the exhaust alarm signal form an "and" logic control strategy for the exhaust.

Claims

1. A photoelectric detection sensor for a hydraulic automatic exhaust valve, characterized in that: include: A photoelectric detection circuit board (1), a ring-shaped detection component, a light source (2), and a photoelectric receiver (3); the ring-shaped detection component includes a ring-shaped detection structure (4), a transmitting lens (5), and a receiving lens (6); The annular detection component is installed in the hydraulic cavity of the automatic exhaust valve, and the photoelectric detection circuit board (1) is installed in the installation cavity of the automatic exhaust valve; the annular detection structure (4) is the structural main body of the annular detection component, and the annular detection cavity inside the annular detection component is a hole structure with thick ends and thin middle, and the transition surface between the middle and the two ends is an inclined surface on one side and a vertical surface on the other side; two transparent installation holes (7) are opened on the inclined surface along the radial direction of the annular detection component, a light source (2) is installed in one installation hole, and the light source (2) and the annular detection cavity are isolated by a transmitting lens (5); a photoelectric receiver (3) is installed in the other installation hole, and the photoelectric receiver (3) and the annular detection cavity are isolated by a receiving lens (6); A photoelectric detection sensor installed inside the exhaust valve detects and identifies the oil and gas liquid level entering the annular detection structure (4); a light source (2) fixedly installed in the mounting hole (7) of the annular detection structure (4) transmits light through a transmitting lens (5); when the medium in the detection cavity is air, the light is transmitted through a receiving lens (6) and received by a photoelectric receiver (3), and transmitted to a photoelectric detection circuit board (1); when the medium in the detection cavity is oil, the light generated by the light source (2) is blocked by the oil through the transmitting lens (5), and no or only a very small amount of light is received by the photoelectric receiver (3) behind the receiving lens (6); and a photocurrent is simultaneously transmitted to the photoelectric detection circuit board (1), which identifies the liquid level according to the difference in light intensity received by the photoelectric receiver (3) under different media, and then outputs an exhaust alarm signal to the outside, and at the same time controls the on-off of the solenoid valve drive circuit according to the exhaust enable signal obtained by input.

2. The sensor according to claim 1, characterized in that The transmitting lens (5) and the receiving lens (6) are respectively glued into two mounting holes (7) at linearly symmetrical positions to form a detection light path.

3. The sensor according to claim 2, characterized in that The transmitting lens (5) forms an angle of 45 degrees with the oil level in the annular detection cavity, and the receiving lens (6) forms an angle of 135 degrees with the oil level in the annular detection cavity.

4. The sensor according to claim 1, characterized in that The photoelectric detection circuit board (1) comprises: a power supply step-down circuit (11), a light source driving circuit (12), a photoelectric conversion circuit (13), a photoelectric threshold comparison circuit (14), an exhaust trigger judgment circuit (15), a solenoid valve driving circuit (16), and an exhaust enabling circuit (17); The power supply step-down circuit is used to reduce the voltage for use by the entire photoelectric detection circuit board (1); The light source driving circuit is used to provide a constant driving current to the light source; The light intensity information output by the photoelectric receiver (3) passes through the photoelectric conversion circuit, the photoelectric threshold comparison circuit, the exhaust trigger judgment circuit, and the electromagnetic valve drive circuit in sequence, and is finally output to the electromagnetic valve drive end, and outputs high and low levels to the outside in the form of an exhaust alarm prompt. When the gas content in the annular detection cavity is too high and exhaust is required, the exhaust alarm signal output is high; when the gas content in the annular detection cavity is not high and exhaust is not required, the exhaust alarm signal output is low.

5. The sensor according to claim 4, characterized in that An anti-shake circuit (18) is provided between the photoelectric threshold comparison circuit and the exhaust trigger judgment circuit.

6. The sensor according to claim 4, characterized in that The solenoid valve drive circuit provides a maximum drive capability of +32V, 2A for the external solenoid valve coil.

7. The sensor according to claim 4, characterized in that The solenoid valve driving circuit specifically controls the action of the solenoid valve according to the exhaust enable signal input from the outside. The exhaust enable signal and the exhaust alarm signal form an "AND" logic control relationship for exhaust control. If the exhaust enable signal has a low logic level, the solenoid valve does not act. If the logic level is high, the solenoid valve is allowed to conduct accordingly according to the liquid level judgment result. The photoelectric detection circuit board (1) also outputs the exhaust alarm state accordingly according to the result of the liquid level judgment.

8. The sensor according to claim 1, wherein The voltage drop range is from +18V to +32V to +5.9±0.1V.

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