Device and method for testing friction force between shell and piston of high-temperature aviation pneumatic valve

Abstract

The invention belongs to the field of tribology application, and particularly discloses a high-temperature aviation pneumatic valve shell-piston friction force testing device and method. The test method is used for simulating and testing the friction force of the high-temperature aviation pneumatic valve shell-piston ring under different working conditions, and provides accurate friction force data for the design and improvement of the high-temperature aviation pneumatic valve. The testing device suitable for the shell-piston friction force of the high-temperature aviation pneumatic valve actuating device comprises a bleed valve piston cylinder, a pull pressure sensor, a linear guide rail, a transmission mechanism and an electric push rod. In the design and simulation stages of the high-temperature aviation pneumatic valve, the high-temperature aviation pneumatic valve shell-piston ring friction force is tested through the method and the device, the design of the high-temperature aviation pneumatic valve can be improved in a targeted mode, and therefore the stability and the safety of the high-temperature aviation pneumatic valve are improved, and the flight safety of an airplane is guaranteed.

Description

Technical Field

[0001] The invention discloses a testing method and device for the friction force between a casing and a piston of a high-temperature aviation pneumatic valve actuating device, and belongs to the field of tribology application. Background Art

[0002] The high-temperature aviation pneumatic valve is a regulating device for the aircraft air source system. It is used in the aircraft air source system and has the function of regulating the system bleed air pressure. It is one of the key components to ensure the flight safety of the aircraft and the safety of life. The high-temperature aviation pneumatic valve disc rotation angle is automatically controlled through the pressure difference on both sides of the piston, so that the bleed air valve outlet pressure is kept constant. The piston is both the actuating component of the high-temperature aviation pneumatic valve and the key component to achieve self-feedback regulation.

[0003] The relative movement between the piston and the housing of a high-temperature aviation pneumatic valve will generate friction, which will change with the service life of the high-temperature aviation pneumatic valve, piston gas temperature, pressure, and piston movement speed, seriously affecting the system pressure control accuracy and response characteristics, and affecting the quality of gas supply to the downstream gas system. The housing-piston friction is a key factor affecting the self-feedback adjustment accuracy of the product. The piston and the housing have high coaxiality. The conventional simple tension sensor measurement method cannot achieve online assembly testing. Establishing a housing-piston friction test method and device suitable for high-temperature aviation pneumatic valve actuators will help evaluate product consistency and qualification, improve the stability of high-temperature aviation pneumatic valves, and thus ensure the flight safety of aircraft. Summary of the invention

[0004] The main purpose of the present invention is to provide a testing method and device for the friction force of the housing and piston of a high-temperature aviation pneumatic valve actuator, so as to simulate and test the friction force of the housing and piston of a high-temperature aviation pneumatic valve under different working conditions, and provide accurate friction force data for the design and improvement of high-temperature aviation pneumatic valves.

[0005] Technical solution: To achieve the above-mentioned purpose, the present invention proposes a high-temperature aviation pneumatic valve housing-piston friction test device, the test device comprising: a pneumatic valve piston cylinder, a tension and pressure sensor, a linear guide rail, a transmission mechanism, and an electric push rod;

[0006] There are two sets of shells and pistons, which are placed symmetrically to balance the air pressure on both sides. At the same time, the two sets of shells and pistons are used for coaxial guidance to avoid measurement errors caused by different axes. Both sets of shells and pistons are connected to high-temperature and high-pressure gas sources to simulate high-temperature and high-pressure working conditions.

[0007] Any housing-piston includes: a housing, a piston, and a connecting rod; the housing and the piston are installed according to the service state; the connecting rod connects two symmetrically placed pistons;

[0008] The transmission mechanism is arranged on the linear guide rail, and the transmission mechanism connects the pneumatic valve piston with the electric push rod;

[0009] The electric push rod is used to provide push and pull forces to drive the piston to move linearly;

[0010] The tension and pressure sensor is installed at the position where the transmission mechanism is connected to the piston cylinder of the air induction valve, and is used for the friction force of the piston ring when the test chamber moves.

[0011] Furthermore, the transmission mechanism includes four transmission rods at the front, rear, left and right sides, and the four transmission rods are arranged in a "mouth" shape; there are rectangular through holes in the middle of the front and rear transmission rods, and there are no openings in the middle of the left and right transmission rods.

[0012] Furthermore, a boss II is provided on the front side of the electric push rod; the boss II of the electric push rod is placed in the middle position of the rear transmission rod hole.

[0013] Furthermore, a boss I is provided in the middle of the connecting rod of the housing-piston; the front transmission rod of the transmission mechanism passes under the piston connecting rod, and the piston connecting rod boss I is placed in the middle position of the front transmission rod hole.

[0014] Furthermore, the rectangular through hole has a through hole width of 20 mm and a length of 30 mm, the rectangular side surface is perpendicular to the movement direction of the electric push rod and the piston, and the boss is in contact with the side surface of the through hole so that the transmitted pulling force is along the movement direction;

[0015] Furthermore, the maximum movement range of the piston is 20 mm, and the speed range is 1 mm / s-20 mm / s.

[0016] Furthermore, the heights of the boss I and boss II are both 5mm-10mm.

[0017] In the test device designed by the present invention, the combination structure of "boss-rectangular through hole" is used to transmit the tensile force of the electric push rod to drive the piston to move. In this structure, there is no fixed connection mechanism between the boss and the rectangular hole, but the normal force is applied by mutual contact. This structure can cleverly eliminate the additional bending moment caused by the misalignment of the assembly between the components of the test device. The double shell-piston is installed oppositely, and the coaxial characteristic of the product is cleverly used to guide the product and avoid introducing measurement errors.

[0018] The purpose of the present invention is to test the friction force of the "housing-piston ring" of the air bleed valve piston. The present invention can realize the friction force test at different temperatures, gas pressures, piston movement speeds and service times.

[0019] At the same time, the present invention also proposes a test method for the friction between the shell and piston of a high-temperature aviation pneumatic valve actuator. The test method adopts the test device as described above. During the test, the two piston cylinders are placed symmetrically, the connecting rod is placed in the middle to connect the two pistons, and then the cylinder is connected to a high-temperature and high-pressure gas source. The connecting rod, the transmission mechanism and the electric push rod are connected in sequence; after standing and waiting for the cylinder temperature and air pressure to stabilize, the electric push rod is turned on to push the piston to reciprocate at a fixed speed through the transmission mechanism; the tension pressure sensors on the left and right sides record the sum of the tension data during reciprocating motion, which is the friction between the shell and the piston ring under the environmental conditions; the air pressure and temperature of the high-temperature and high-pressure gas source, as well as the speed of the electric push rod, can be modified to obtain the friction between the shell and the piston ring in different service environments.

[0020] Technical effect: The present invention designs a testing method and device for the friction between the housing and the piston of a high-temperature aviation pneumatic valve actuator, which can simulate and test the friction between the housing and the piston ring of a high-temperature aviation pneumatic valve under different working conditions, and provide accurate friction data for the design and improvement of high-temperature aviation pneumatic valves. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of a high-temperature aviation pneumatic valve housing-piston friction force testing device;

[0022] Figure 2 Schematic diagram of the housing-piston structure;

[0023] Figure 3 It is a schematic diagram of the transmission mechanism structure;

[0024] Figure 4 is a schematic diagram of boss Ⅰ;

[0025] Figure 5 This is a schematic diagram of boss II.

[0026] Among them, 1-air valve piston cylinder, 2-pull pressure sensor, 3-linear guide, 4-transmission mechanism, 5-electric push rod, 11-housing, 12-piston, 13-connecting rod; 41-front transmission rod, 42-right transmission rod, 43-left transmission rod, 44-rear transmission rod DETAILED DESCRIPTION

[0027] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example 1

[0029] The present invention provides a test method and device for the friction force between the housing and piston of a high-temperature aviation pneumatic valve actuator, so as to simulate and test the friction force between the housing and piston ring of a high-temperature aviation pneumatic valve under different working conditions, and provide accurate measured data for the friction force model. The test device for the friction force between the housing and piston of a high-temperature aviation pneumatic valve actuator includes: an air bleed valve piston cylinder (1), a tension and compression sensor (2), a linear guide rail (3), a transmission mechanism (4), and an electric push rod (5).

[0030] There are two sets of the air bleed valve cylinders, which are symmetrically placed to balance the air pressure on both sides. The two pistons are guided by coaxial characteristics to avoid introducing measurement errors. Both sets of cylinders are connected to a high-temperature and high-pressure air source.

[0031] The air bleed valve piston cylinder includes: a housing, a piston, and a connecting rod.

[0032] The housing and the piston are installed according to the service state. The connecting rod connects the two symmetrically placed pistons.

[0033] There is a boss Ⅰ in the middle of the piston connecting rod, and the height of the boss Ⅰ is 5 mm - 10 mm.

[0034] The transmission mechanism includes four transmission rods, and the four transmission rods are arranged in a "square" shape. The plane where the square-shaped transmission mechanism is located is parallel to the horizontal plane, and the directions of the transmission rods on the left and right sides are parallel to the piston axis. There are rectangular through holes in the middle of the front and rear transmission rods, the width of the through holes is 20 mm, and the length is 30 mm. The front and rear side surfaces of the rectangular through holes are perpendicular to the piston axis.

[0035] The transmission rods on the left and right sides are installed on the linear guide rail.

[0036] The front transmission rod passes under the piston connecting rod, and the boss Ⅰ of the piston connecting rod is placed in the middle position of the hole of the front transmission rod.

[0037] The tension and compression sensor is installed at the position where the transmission rods on the left and right sides are connected to the front transmission rod, and is used to test the friction force when the piston ring moves.

[0038] The electric push rod is used to provide pushing and pulling forces to drive the piston to move. Its maximum movement range is 20 mm, and the speed range is 1 mm / s - 20 mm / s.

[0039] There is a boss Ⅱ on the front side of the electric push rod, and the height of the boss Ⅱ is 5 mm - 10 mm.

[0040] The boss Ⅱ of the electric push rod is placed in the middle position of the hole of the rear transmission rod.

[0041] The combination structure of "boss-rectangular through hole" is used to transmit the tensile force of the electric push rod to drive the piston to move. There is no fixed connection mechanism between the boss and the rectangular hole of this structure, but the normal force is applied by mutual contact. This structure can cleverly eliminate the extra bending moment caused by the misalignment of the assembly of the various components of the test device.

[0042] The electric push rod drives the piston to reciprocate through the transmission mechanism, and the friction between the housing and the piston ring under different working conditions can be measured. The specific steps include:

[0043] (1) Connect the electric push rod, transmission mechanism, linear guide, tension and pressure sensor, and housing-piston in sequence. The electric push rod, linear guide, and housing are fixed to the workpiece table through tooling. The piston connecting rod boss I and the electric push rod boss II are placed in the center of the rectangular through hole of the front and rear transmission rods of the transmission mechanism.

[0044] (2) The housing-piston, left and right transmission rods, and electric push rod are coaxial;

[0045] (3) The plane where the transmission mechanism is located is parallel to the horizontal plane;

[0046] (4) Connect the shell to a high-temperature and high-pressure gas source, and adjust the temperature and pressure to the values ​​under different working conditions. Let it stand for 10 minutes to ensure that the temperature in the cylinder is consistent.

[0047] (5) Control the electric push rod to reciprocate at a speed v, and the movement stroke is fixed at 20 mm.

[0048] (6) The electric push rod drives the transmission mechanism and the piston in sequence through the combined structure of "boss-rectangular hole" through normal contact.

[0049] (7) Boss I and boss II have spherical structures on both the front and rear sides;

[0050] (8) When the piston is pushed, the boss is in normal contact with the front side of the rectangular through hole;

[0051] (9) In the pull piston type, the boss is in normal contact with the rear side of the rectangle;

[0052] (10) Record the force data F1 and F2 of the tension pressure sensors on the left and right sides. At this time, the friction force between the housing and the piston ring is F = (F1 + F2) / 2.

[0053] (11) Modify the air source temperature, air pressure, and push rod speed, and test the relationship between the friction force and the position of the piston in the shell under different working conditions.

[0054] (12) The average friction force between the two housings and the piston is measured by the above embodiment;

[0055] (13) Furthermore, by taking three housing-pistons and testing them in pairs, the friction force of each piston in the housing can be measured.

[0056] The above specific implementation methods or cases are only used to explain the technical solutions of the present invention, and are not intended to limit the present invention. Any parts not described in detail are regarded as conventional technical means in the art. A person of ordinary skill in the art should understand that based on the design concept of the present application, the technical solutions described in the aforementioned implementation methods should be adaptively modified, or some or all of the technical features therein should be replaced by equivalents. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high temperature aviation pneumatic valve housing-piston friction test device, characterized in that: The testing device comprises: a pneumatic valve piston cylinder, a tension and pressure sensor, a linear guide rail, a transmission mechanism, and an electric push rod; There are two sets of shells and pistons, which are placed symmetrically to balance the air pressure on both sides. At the same time, the two sets of shells and pistons are used for coaxial guidance to avoid measurement errors caused by different axes. Both sets of shells and pistons are connected to high-temperature and high-pressure gas sources to simulate high-temperature and high-pressure working conditions. Any housing-piston includes: a housing, a piston, and a connecting rod; the housing and the piston are installed according to the service state; the connecting rod connects two symmetrically placed pistons; The transmission mechanism is arranged on the linear guide rail, and the transmission mechanism connects the pneumatic valve piston with the electric push rod; The electric push rod is used to provide push and pull forces to drive the piston to move linearly; The tension and pressure sensor is installed at the position where the transmission mechanism is connected to the piston cylinder of the air induction valve, and is used for the friction force of the piston ring when the test chamber moves.

2. A high temperature aviation pneumatic valve housing-piston friction force testing device as claimed in claim 1, characterized in that: The transmission mechanism comprises four transmission rods at the front, rear, left and right sides, and the four transmission rods are arranged in a "mouth" shape; there are rectangular through holes in the middle of the front and rear transmission rods, and there are no openings in the middle of the left and right transmission rods.

3. A high temperature aviation pneumatic valve housing-piston friction force testing device as claimed in claim 2, characterized in that: The rectangular through hole has a width of 20 mm and a length of 30 mm. The rectangular side surface is perpendicular to the movement direction of the electric push rod and the piston. The above-mentioned boss contacts the side surface of the through hole so that the transmitted pulling force is along the movement direction.

4. A high temperature aviation pneumatic valve housing-piston friction force testing device as claimed in claim 1, characterized in that: The front side of the electric push rod is provided with a boss II; the boss II of the electric push rod is placed in the middle position of the rear transmission rod hole.

5. A high temperature aviation pneumatic valve housing-piston friction force testing device as claimed in claim 1, characterized in that: A boss I is provided in the middle of the connecting rod of the housing-piston; the front transmission rod of the transmission mechanism passes through below the piston connecting rod, and the piston connecting rod boss I is placed in the middle position of the front transmission rod hole.

6. A high temperature aviation pneumatic valve housing-piston friction test device as claimed in claim 1, characterized in that: There is a boss I in the middle of the connecting rod of the housing-piston and a boss II on the front side of the electric push rod, both of which are 5mm-10mm in height.

7. A high temperature aviation pneumatic valve housing-piston friction force testing device as claimed in claim 1, characterized in that: The maximum movement range of the piston is 20 mm, and the speed range is 1 mm / s-20 mm / s.

8. A method for testing the friction between the housing and piston of a high-temperature aviation pneumatic valve actuator, the method using a testing device as claimed in any one of claims 1 to 7 to implement friction testing at different temperatures, gas pressures, piston movement speeds and service times, characterized in that: During the test, the two piston cylinders are placed symmetrically, with the connecting rod placed in the middle to connect the two pistons, and then the cylinders are connected to a high-temperature and high-pressure gas source; the connecting rod, transmission mechanism and electric push rod are connected in sequence; after standing still and waiting for the cylinder temperature and air pressure to stabilize, the electric push rod is turned on to push the piston to reciprocate at a fixed speed through the transmission mechanism; the tension and pressure sensors on the left and right sides record the sum of the tension data during reciprocating motion, which is the friction force between the shell and the piston ring under the environmental conditions; by modifying the air pressure and temperature of the high-temperature and high-pressure gas source, as well as the speed of the electric push rod, the friction force between the shell and the piston ring in different service environments can be obtained.

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