Automobile brake vacuum degree pressure sensor

Abstract

The utility model relates to the technical field of automobile braking, in particular to an automobile braking vacuum degree pressure sensor which comprises a vacuum degree pressure sensor assembly, a circuit board is arranged on the vacuum degree pressure sensor assembly, and a pressure sensor chip is integrated on the circuit board. The vacuum degree pressure sensor assembly is provided with a circuit board, capacitors are arranged at the input end and the output end of the pressure sensor chip on the circuit board, the vacuum degree pressure sensor assembly is further provided with a shell, the circuit board is installed in the shell, a pressure detection chamber and an air inlet chamber are arranged above and below the circuit board in the shell respectively, and the pressure sensor chip is arranged in the pressure detection chamber. According to the automobile brake vacuum degree pressure sensor, most of air disturbance is filtered out by internal air resistance of the part, back to the air inlet, of the pressure sensor chip, and pressure fluctuation is smoother, so that the air pressure fluctuation is far smaller than that of the scheme facing the air inlet, and the situation that output is low to a clamping position is effectively solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of automobile brake, concretely is a kind of automobile brake vacuum degree pressure sensor. BACKGROUND

[0002] Automobile brake vacuum degree pressure sensor is an important component in modern automobile brake system, especially in those vehicles using vacuum booster to assist braking, the main function is to monitor the vacuum level of brake system to ensure that brake system can work normally.

[0003] At present, the pressure sensor chip is towards the air inlet part, under the whole vehicle installation, assembly piece is installed on vacuum tank, negative pressure vacuum tank is connected with negative pressure pump, driver steps on pedal many times, when negative pressure pump is extracted to 20kpa (A), under the outside mechanical vibration, the lower air damping, MEMS diaphragm approaches free state, outside disturbance is easy to trigger MEMS to produce resonance, so that the output voltage of piezoresistive sensor can be as low as clamping, and the phenomenon after retest is not reproducible, and in the assembly process, due to the existence of outside mechanical vibration, uneven stress of capacitor, easy to split. UTILITY MODEL CONTENT

[0004] The utility model aims at providing a kind of automobile brake vacuum degree pressure sensor to solve the problem that piezoresistive absolute pressure sensor in current market is in high vacuum degree (<20kpa) environment, air damping sharply reduces, MEMS membrane is more susceptible to external force interference, resonance is generated, and under the condition of outside mechanical vibration, it can cause output abnormal jump.

[0005] To achieve the above object, the utility model provides the following technical scheme: a kind of automobile brake vacuum degree pressure sensor, including vacuum degree pressure sensor assembly, vacuum degree pressure sensor assembly is equipped with circuit board, and pressure sensor chip is integrated on circuit board, and capacitor is set on the input end and the output end of pressure sensor chip on circuit board, vacuum degree pressure sensor assembly is also equipped with shell, and circuit board is installed in shell, and pressure detection chamber and air inlet chamber are respectively equipped in the upper and lower of circuit board in shell, and pressure sensor chip is located in pressure detection chamber.

[0006] Preferably, the circuit board and the shell are connected by bonding process.

[0007] Preferably, the shell side is integrally provided with a negative pressure pump connector, and the negative pressure pump connector is provided with an air inlet.

[0008] Preferably, the air inlet side is uniformly and evenly provided with through holes in communication with the air inlet chamber.

[0009] Preferably, the pressure sensor chip is arranged back to the air inlet.

[0010] Preferably, the pressure detection chamber and the air inlet chamber are communicated with each other, and the pressure detection chamber is further communicated with an exhaust pipeline.

[0011] Compared with the prior art, the automobile brake vacuum degree pressure sensor has the following beneficial effects:

[0012] 1. The automobile brake vacuum degree pressure sensor arranges the pressure sensor chip back to the air inlet part, filters most of the air disturbance in the internal air resistance, and the pressure fluctuation is more gentle, so that the air pressure fluctuation is much smaller than the scheme towards the air inlet, and the output is effectively solved to the clamping position.

[0013] 2. The automobile brake vacuum degree pressure sensor is redundantly designed at the sensor output end and the input end, and two capacitors are additionally arranged, when one capacitor is cracked and fails, the other capacitor can also play a protection effect.

[0014] 3. The automobile brake vacuum degree pressure sensor arranges the pressure sensor chip back to the air inlet part, avoids that the dirt such as oil and gas easily enters the sensor chip part through the air nozzle, and thus avoids affecting the sensor output. BRIEF DESCRIPTION OF DRAWINGS

[0015] Fig. 1 The automobile brake vacuum degree pressure sensor designed according to the principle diagram of the utility model;

[0016] Fig. 2 The automobile brake vacuum degree pressure sensor is arranged on the circuit board according to the layout structure schematic diagram of the utility model;

[0017] Fig. 3 The automobile brake vacuum degree pressure sensor assembly sectional view of the utility model.

[0018] In the drawing: 1, circuit board; 2, pressure sensor chip; 3, shell; 4, negative pressure pump connector; 5, air inlet; 6, pressure detection chamber; 7, exhaust pipeline; 8, air inlet chamber; 9, vacuum degree pressure sensor assembly. DETAILED DESCRIPTION

[0019] The technical scheme in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.

[0020] Please refer to Figs. 1-3The utility model provides a technical scheme: a kind of automobile brake vacuum degree pressure sensor, including vacuum degree pressure sensor assembly 9, vacuum degree pressure sensor assembly 9 is equipped with circuit board 1, and pressure sensor chip 2 is integrated on circuit board 1, and capacitor is set on the input end and the output end of pressure sensor chip 2 on circuit board 1, by redundancy design, after one capacitor crack failure, another capacitor can also play protective effect, vacuum degree pressure sensor assembly 9 is also equipped with shell 3, and circuit board 1 is installed in shell 3, bonding process connection is used between circuit board 1 and shell 3, this structure since pressure sensor chip 2 is located above circuit board 1 position, therefore circuit board 1 can be conveniently fixed into shell 3 by bonding process, bonding process is a kind of technology that semiconductor chip is directly connected to substrate or other carrier, compared with the fixed mode when sensor chip is towards air nozzle, this procedure operation is simpler, shell 3 side is integrally provided with negative pressure pump connector 4, and negative pressure pump connector 4 is equipped with air inlet 5, this structure makes shell 3 can be connected negative pressure pump, changes the air pressure value in shell 3 by negative pressure pump, to further change the air pressure value in pressure sensor chip 2, and shell 3 is equipped with pressure detection chamber 6 and air inlet chamber 8 respectively above and below circuit board 1, air inlet 5 side is evenly spaced apart and provided with the through hole that is connected with air inlet chamber 8, this structure can make high-pressure gas enter air inlet chamber 8 by air inlet 5, and filter out most air disturbance by the setting of through hole, let pressure fluctuation be more gentle, reduce the influence of vibration on the installation stability of circuit board 1, and ensure the reliability of pressure sensor chip 2 installation, and pressure sensor chip 2 is located in pressure detection chamber 6, pressure sensor chip 2 back to air inlet 5 one end, this structure makes high-pressure gas enter air inlet chamber 8 after air inlet 5, can avoid gas directly acting on pressure sensor chip 2, effectively avoid the problem that dirty such as oil gas enters sensor chip part, to avoid affecting sensor output, pressure detection chamber 6 and air inlet chamber 8 are interconnected, and pressure detection chamber 6 is also connected with exhaust duct 7, this structure makes air pressure be everywhere equal in pressure detection chamber 6 and air inlet chamber 8, ensure the accuracy of air pressure detection, exhaust duct 7 is used for discharging pressure gas, play the role of explosion-proof.

[0021] Working principle: when using the automobile brake vacuum degree pressure sensor, first, the circuit board 1 of the vacuum degree pressure sensor assembly 9 is installed in the shell 3, the pressure sensor chip 2 is integrated on the circuit board 1, the shell 3 is connected with the negative pressure pump through the negative pressure pump connecting head 4, the air pressure value in the tank is changed through the negative pressure pump, the gas reaches the air inlet chamber 8 through the air inlet 5 first, and then enters the pressure detection chamber 6, since the pressure sensor chip 2 is opposite to the air inlet 5, the problem that dirty such as oil and gas enters the sensor chip part is effectively improved, so as to prevent the sensor output from being affected, meanwhile, most of the air disturbance is filtered out in the internal air resistance, the pressure fluctuation is more gentle, the condition that the sensor output is as low as the clamping state is effectively solved, finally, the high-pressure gas is discharged through the exhaust pipe 7, so a series of work is completed.

[0022] Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments or make equivalent replacement to part of the technical features, and any modification, equivalent replacement, improvement, etc. within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A vehicle brake vacuum pressure sensor, comprising a vacuum pressure sensor assembly (9), characterized in that: The vacuum pressure sensor assembly (9) is provided with a circuit board (1), and a pressure sensor chip (2) is integrated on the circuit board (1). Capacitors are provided on both the input and output terminals of the pressure sensor chip (2) on the circuit board (1). The vacuum pressure sensor assembly (9) is also provided with a housing (3), and the circuit board (1) is installed inside the housing (3). A pressure detection chamber (6) and an air inlet chamber (8) are respectively provided above and below the circuit board (1) inside the housing (3). The pressure sensor chip (2) is located inside the pressure detection chamber (6).

2. The automotive brake vacuum pressure sensor according to claim 1, characterized in that: The circuit board (1) and the housing (3) are connected by a bonding process.

3. The automotive brake vacuum pressure sensor according to claim 1, characterized in that: The housing (3) is integrally provided with a negative pressure pump connector (4) on its side, and the negative pressure pump connector (4) is provided with an air inlet (5).

4. The automotive brake vacuum pressure sensor according to claim 3, characterized in that: The air inlet (5) has through holes that are evenly spaced on its side and communicate with the air inlet chamber (8).

5. The automotive brake vacuum pressure sensor according to claim 3, characterized in that: The pressure sensor chip (2) is positioned away from the air inlet (5).

6. The automotive brake vacuum pressure sensor according to claim 1, characterized in that: The pressure detection chamber (6) and the air intake chamber (8) are interconnected, and the pressure detection chamber (6) is also connected to an exhaust pipe (7).

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