High-frequency hydraulic pulsation signal generating device and method based on cam profile design

Abstract

The invention discloses a high-frequency hydraulic pulsation signal generating device and method based on cam profile design, and relates to the technical field of aero-engine tests. The test system is connected to a main hydraulic system with a constant flow source in parallel, and main system pressure pulsation adjustment is achieved in a bypass pressure adjustment mode. According to the system, a cam and a connecting rod are driven by a high-speed motor, the opening degree of a throttling device is changed, and then pressure pulsation output is achieved. The system guarantees the pressure regulation precision through machining and assembling precision, has the advantages of being wide in frequency range, stable in performance and high in universality, can be used for hydraulic element pressure response characteristic test research, and can also be used for verifying the dynamic response index of a hydraulic pressure transmitter.

Description

Technical Field

[0001] The invention belongs to the technical field of aero-engine testing, and in particular relates to a high-frequency hydraulic pulsation signal generating device and method based on cam profile design. Background Art

[0002] In the process of conducting frequency characteristic research on mechanical hydraulic products of aircraft engines, it is necessary to study the frequency response characteristics of hydraulic sensing components (such as pressure sensors) or pressure control components (such as differential pressure valves). Dynamic test is an important part of the research process, so it is necessary to build a hydraulic pulsation signal generation system with a large frequency range and controllable to provide dynamic input signals for the test object. By statistically analyzing the response data of the test object after dynamic test, its frequency response characteristics can be obtained. Among them, the hydraulic pulsation signal generation system is a key system, and there is currently no relevant technical solution in the industry. Summary of the invention

[0003] Based on the above background, a method for amplitude control of high-frequency hydraulic pulsation signal is provided for frequency response characteristic test of hydraulic components. The frequency control of hydraulic pulsation signal is realized by controlling the motor speed. And the amplitude control of hydraulic pulsation signal is realized by designing the cam profile.

[0004] In view of this, according to one aspect of an embodiment of the present invention, a high-frequency hydraulic pulsation signal generating device based on a cam profile design is provided, comprising: a high-frequency response pressure transmitter 1, a pressure regulating device 2, and an oil tank 3; the inlet of the pressure regulating device 2 is connected to the main system, and the outlet is connected to the oil tank 3, the pressure of the oil tank 3 is a constant value, and the high-frequency response pressure transmitter 1 is used to measure the actual hydraulic pulsation value; the pressure regulating device 2 comprises a high-speed motor 4, a cam 5, a slide rail 6, a locking nut 7, a connecting rod 8, and a throttling device 9, wherein the output shaft of the high-speed motor 4 is coaxially fixedly connected to the cam 5, and the slide rail 6 is connected to the main system through the connecting rod 8. The valve stem 10 is threadedly connected and locked by a locking nut 7. The axes of the connecting rod 8 and the valve stem 10 are perpendicular to and intersect with the axis of the motor 4. The cam 5 is a variable diameter shape, and its outer contour arc surface is parallel to the axis of the motor 4. The outer contour edge of the cam 5 is slidably connected with the slide rail 6, so that when the cam 5 rotates, the slide rail 6 slides on the outer contour edge of the cam 5, driving the connecting rod 8 to move axially; the high-speed motor 4 and the throttling device 9 are relatively fixed, so that the motor 4 drives the cam 5 to rotate, and the change in the outer contour size of the cam 5 is converted into a change in the opening of the throttling device 9 through the connecting rod 8 and the slide rail 6. The throttling device 9 is used to output a hydraulic pulsation signal.

[0005] Optionally, the throttling device includes a valve stem 10, a limiting guide sleeve 11, a valve core 12, and a valve body 13. A valve cavity is arranged inside the valve body 13. The inner end of the valve stem 10 is fixedly connected to the valve core 12, and the outer end of the valve stem 10 is fixedly connected to the connecting rod 8. The valve core 12 is located in the valve cavity. The limiting guide sleeve 11 is arranged at the outer end of the valve cavity. The valve stem 10 passes through the limiting guide sleeve 11 to limit the maximum position of the valve core 12 and ensure that the movement direction of the valve stem 10 is concentric with the valve cavity. A sealing structure is arranged between the limiting guide sleeve 11 and the valve stem 10 and the valve body 13.

[0006] Optionally, the slide rail 6 also includes an upper ball 61, a lower ball 62 and a retaining frame 63, and the upper ball 61 and the lower ball 62 are in close contact with the upper surface and the lower surface of the outer edge of the cam 5 respectively; the retaining frame 63 is used to constrain the positions of the upper ball 61 and the lower ball 62, and is fixedly connected to the connecting rod 8.

[0007] Optionally, the cam 5 is of an axisymmetric shape.

[0008] Optionally, a scale is printed on the valve stem 10 to display the moving position of the valve core 12 .

[0009] According to another aspect of the embodiments of the present invention, a method for generating a high-frequency hydraulic pulsation signal based on a cam profile design is provided, and any of the above-mentioned devices is used to output a hydraulic pulsation signal.

[0010] Optionally, the system pressure is set by adjusting the position of the valve stem 10 .

[0011] Optionally, the hydraulic pulsation signal required by the tested product is discretized, and the position of the valve stem 10 corresponding to each hydraulic pulsation signal can be obtained according to the test, and the size of the cam can be calculated.

[0012] The amplitude of hydraulic pulsation signal can be controlled by designing cam profile. The frequency of hydraulic pulsation signal can be controlled by controlling motor speed. The designed pressure regulating device can control the amplitude and signal frequency of high-frequency hydraulic pulsation, and provide a test method for the research needs of frequency response characteristics of hydraulic sensing components (such as pressure sensors) or pressure control components (such as differential pressure valves). BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is the hydraulic principle diagram of this hydraulic pulsation signal generating system.

[0014] Among them, 1 is a high-frequency response pressure transmitter, 2 is a pressure regulating device, and 3 is an oil tank.

[0015] Figure 2 This is a diagram of the structure of the voltage regulating device.

[0016] Among them, 4 is a high-speed motor, 5 is a cam, 6 is a slide rail, 7 is a locking nut, 8 is a connecting rod, and 9 is a throttling device.

[0017] Figure 3 This is a diagram of the structure of the throttling device.

[0018] Among them, 10 is a valve stem, 11 is a limiting guide sleeve, 12 is a valve core, and 13 is a valve body.

[0019] Figure 4 It is a connection diagram of the slide rail, connecting rod and valve stem.

[0020] Figure 5 This is the hydraulic pulsation signal diagram.

[0021] Among them, the horizontal axis is time, and the vertical axis is target pressure.

[0022] Figure 6(a) and Figure 6(b) are pressure-position relationship diagrams.

[0023] Among them, Figure (a) is a pressure-position curve formed after fitting, the horizontal axis is the opening position of the valve stem 10, and the vertical axis is the corresponding target pressure. Figure (b) is a pressure-position relationship diagram of a single hydraulic pulsation, the horizontal axis is the opening position of the valve stem 10, and the vertical axis is the pressure value.

[0024] Figure 7 This is a dimension relationship diagram.

[0025] Figure 8 This is the cam outline dimension drawing. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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.

[0027] According to one aspect of an embodiment of the present invention, a high-frequency hydraulic pulsation signal generating device based on a cam profile design is provided, comprising: a high-frequency response pressure transmitter 1, a pressure regulating device 2, and an oil tank 3; the inlet of the pressure regulating device 2 is connected to the main system, and the outlet is connected to the oil tank 3, the pressure of the oil tank 3 is a constant value, and the high-frequency response pressure transmitter 1 is used to measure the actual hydraulic pulsation value; the pressure regulating device 2 comprises a high-speed motor 4, a cam 5, a slide rail 6, a locking nut 7, a connecting rod 8, and a throttling device 9, wherein the output shaft of the high-speed motor 4 is coaxially fixedly connected to the cam 5, and the slide rail 6 is connected to the valve stem through the connecting rod 8. 10 is threadedly connected and locked by a locking nut 7. The axes of the connecting rod 8 and the valve stem 10 are perpendicular to and intersect with the axis of the motor 4. The cam 5 is a variable diameter shape, and its outer contour arc surface is parallel to the axis of the motor 4. The outer contour edge of the cam 5 is slidably connected with the slide rail 6, so that when the cam 5 rotates, the slide rail 6 slides on the outer contour edge of the cam 5, driving the connecting rod 8 to move axially; the high-speed motor 4 and the throttling device 9 are relatively fixed, so that the motor 4 drives the cam 5 to rotate, and the change in the outer contour size of the cam 5 is converted into the change in the opening of the throttling device 9 through the connecting rod 8 and the slide rail 6. The throttling device 9 is used to output a hydraulic pulsation signal.

[0028] Furthermore, the throttling device includes a valve stem 10, a limiting guide sleeve 11, a valve core 12, and a valve body 13. A valve cavity is arranged inside the valve body 13. The inner end of the valve stem 10 is fixedly connected to the valve core 12, and the outer end of the valve stem 10 is fixedly connected to the connecting rod 8. The valve core 12 is located in the valve cavity. The limiting guide sleeve 11 is arranged at the outer end of the valve cavity. The valve stem 10 passes through the limiting guide sleeve 11 to limit the maximum position of the valve core 12 and ensure that the movement direction of the valve stem 10 is concentric with the valve cavity. A sealing structure is arranged between the limiting guide sleeve 11 and the valve stem 10 and the valve body 13.

[0029] Furthermore, the slide rail 6 also includes an upper ball 61, a lower ball 62 and a retaining frame 63. The upper ball 61 and the lower ball 62 are in close contact with the upper surface and the lower surface of the outer edge of the cam 5 respectively; the retaining frame 63 is used to constrain the positions of the upper ball 61 and the lower ball 62, and is fixedly connected to the connecting rod 8.

[0030] Furthermore, the cam 5 is of an axisymmetric shape.

[0031] Furthermore, a scale is printed on the valve stem 10 to display the moving position of the valve core 12 .

[0032] According to another aspect of the embodiments of the present invention, a method for generating a high-frequency hydraulic pulsation signal based on a cam profile design is provided, and any of the above-mentioned devices is used to output a hydraulic pulsation signal.

[0033] Furthermore, the system pressure is set by adjusting the position of the valve stem 10 .

[0034] Furthermore, the hydraulic pulsation signal required by the tested product is discretized, and the position of the valve stem 10 corresponding to each hydraulic pulsation signal can be obtained according to the test, and the size of the cam can be calculated.

[0035] This test system is connected in parallel to the main hydraulic system with a constant current source, and the pressure pulsation regulation of the main system is achieved by bypass pressure regulation. The system realizes the change of the opening of the throttling device by driving the cam and connecting rod with a high-speed motor, thereby realizing the output of pressure pulsation. This system ensures the pressure regulation accuracy through processing and assembly accuracy. It has the advantages of wide frequency range, stable performance and strong versatility. It can be used for the test and research of the pressure response characteristics of hydraulic components, and can also be used to verify the dynamic response index of hydraulic pressure transmitters.

[0036] Example

[0037] From the hydraulic principle diagram of the hydraulic pulsation signal generating system ( Figure 1 ) It can be seen that the system realizes hydraulic pulsation regulation through bypass pressure regulation. The inlet of the pressure regulating device 2 is connected to the main system, and the outlet is connected to the oil tank 3. The tank pressure is a constant value, and the high-frequency response pressure transmitter 1 is used to measure the actual hydraulic pulsation value.

[0038] From the structure diagram of the voltage regulating device ( Figure 2 ) and the connection diagram of the slide rail, connecting rod and valve stem ( Figure 4 ) It can be seen that the pressure regulating device 2 is composed of a high-speed motor 4, a cam 5, a slide rail 6, a locking nut 7, a connecting rod 8, and a throttling device 9; the slide rail 6 is composed of an upper ball 61, a lower ball 62, and a retaining frame 63. The high-speed motor 4 is coaxially fixedly connected to the cam; the upper and lower balls 62 of the slide rail 6 are in close contact with the upper and lower surfaces of the outer edge of the cam 5 respectively; the slide rail 6 is threadedly connected to the valve stem 10 through the connecting rod 8 and is locked by the locking nut 7. The axis of the connecting rod 8 and the valve stem 10 is perpendicular to and intersects with the axis of the motor 4; the cam 5 is axially symmetrical, and its outer arc surface is parallel to the axis of the motor 4.

[0039] The high-speed motor 4 is relatively fixed to the throttling device 9. The motor drives the cam to rotate, and the change of the cam outer profile size is converted into the change of the valve core opening of the throttling device 9 through the connecting rod 8 and the slide rail 6, thereby realizing dynamic regulation of the system pressure.

[0040] From the throttling device structure diagram ( Figure 3 ) It can be seen that the throttling device is composed of a valve stem 10, a limit guide sleeve 11, a valve core 12, and a valve body 13. The valve stem 10 is printed with a scale to display the moving position of the valve core; the limit guide sleeve 11 is used to limit the maximum position of the valve core 12 and ensure that the movement direction of the valve stem 10 is concentric with the valve cavity; a sealing structure is provided between the limit guide sleeve 11 and the valve stem 10 and the valve body 13; X is used to represent the current position of the valve core 12, and when the valve core 12 is in contact with the limit guide sleeve 11, X takes the maximum value.

[0041] From the hydraulic pulsation signal diagram ( Figure 5 ) It can be seen that the horizontal axis is the time axis, the vertical axis is the pressure value, and the pressure pulsation from P1 to Pn and then to P1 is a pressure pulsation, and it takes time t to complete a pressure pulsation.

[0042] Discretize a single hydraulic pulsation signal and evenly divide it into n values: P1, P2, ... Pn. Figure 1 ) is used to set the system pressure by adjusting the position of the valve stem 10 of the throttling device, while ensuring that other conditions remain unchanged. The system pressure is adjusted to P1, P2, ... Pn respectively, and the corresponding positions X1, X2, ... Xn of the valve stem 10 are recorded to form a pressure-position relationship diagram (Figure 6(a)). The pressure-position curve is fitted into a smooth curve through calculation software.

[0043] Figure 7 It is a dimensional relationship diagram, R represents the distance from the cam axis to the outer profile, L represents the distance from the cam axis to the valve body, C represents the distance from the cam outer profile to the top of the valve stem, C and L are design values ​​and are constants, and the value of R can be obtained as follows:

[0044] R=LCX

[0045] Figure 8 is the outline dimension diagram of cam 5, and θ represents the minimum equally divided angle.

[0046]

[0047] Among them, s means that the cam is divided into s sectors from the axis; m means that the X curve is divided into m values: X1, X2, ...Xm (as shown in Figure 6 (b)). According to the value of X and the relationship between R and X, a continuous and smooth cam arc surface can be designed. The s arc surfaces form an axisymmetric cam profile. The high-speed motor completes s pulsating pressure adjustments for each rotation. The hydraulic pulsation frequency is represented by H, and the motor speed is represented by η. Then:

[0048] H=s·η

[0049] For the design and processing of the cam, the formula should be used for calculation according to the requirements of the tested product for the hydraulic pulsation signal. First, the hydraulic pulsation signal P required by the tested product should be discretized. According to the test, the X value corresponding to each hydraulic pulsation signal can be obtained. According to the above formula, the value of the cam radius R can be calculated.

[0050] Before starting the hydraulic pulsation test, first press Figure 1 Install the pipeline as shown, and supply oil to the main system from a stable constant current source. Figure 4As shown, the slide rail 6, connecting rod 8, and valve stem 10 are connected and fixed with locking nut 8, and then press Figure 3 As shown, the throttling device is installed, and finally the high-speed motor 4 is connected to the cam 5.

[0051] After the hydraulic pulsation test begins, the motor 4 drives the cam 5 to rotate, causing the valve stem 10 to continuously move up and down, thereby affecting the displacement of the valve core 12, resulting in a continuous change in the hydraulic pulsation. In the test, the frequency of the hydraulic pulsation sinusoidal signal is changed by changing the speed of the motor 4. The motor speed η can be calculated by the above formula, and finally a hydraulic pulsation signal that meets the requirements of the test piece can be obtained.

[0052] The above is only a specific embodiment of the present invention, and the present invention is described in detail. The unexplained part is a conventional technology. However, the protection scope of the present invention is not limited to this. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A high-frequency hydraulic pulsation signal generating device based on a cam profile design, characterized in that: include: High-frequency response pressure transmitter (1), pressure regulating device (2), oil tank (3); The inlet of the pressure regulating device (2) is connected to the main system, and the outlet is connected to the oil tank (3). The pressure of the oil tank (3) is a constant value, and the high-frequency response pressure transmitter (1) is used to measure the actual hydraulic pulsation value; The pressure regulating device (2) comprises a high-speed motor (4), a cam (5), a slide rail (6), a locking nut (7), a connecting rod (8), and a throttling device (9), wherein the output shaft of the high-speed motor (4) is coaxially fixedly connected to the cam (5), the slide rail (6) is threadedly connected to the valve stem (10) through the connecting rod (8) and is locked by the locking nut (7), and the axis of the connecting rod (8) and the valve stem (10) is perpendicular to and intersects with the axis of the motor (4); the cam (5) is of a variable diameter shape, and its outer contour arc surface is aligned with the motor (4). The axes are parallel, and the outer edge of the cam (5) is slidably connected to the slide rail (6), so that when the cam (5) rotates, the slide rail (6) slides on the outer edge of the cam (5), driving the connecting rod (8) to move axially; the high-speed motor (4) and the throttling device (9) are relatively fixed, so that the motor (4) drives the cam (5) to rotate, and the change of the outer size of the cam (5) is converted into the change of the opening of the throttling device (9) through the connecting rod (8) and the slide rail (6), and the throttling device (9) is used to output a hydraulic pulsation signal.

2. The device according to claim 1, characterized in that The throttling device comprises a valve stem (10), a limiting guide sleeve (11), a valve core (12), and a valve body (13); a valve inner cavity is arranged inside the valve body (13); the inner end of the valve stem (10) is fixedly connected to the valve core (12); the outer end of the valve stem (10) is fixedly connected to a connecting rod (8); the valve core (12) is located in the valve inner cavity; the limiting guide sleeve (11) is arranged at the outer end of the valve inner cavity; the valve stem (10) passes through the limiting guide sleeve (11) to limit the maximum position of the valve core (12) and ensure that the movement direction of the valve stem (10) is concentric with the valve inner cavity; a sealing structure is arranged between the limiting guide sleeve (11), the valve stem (10), and the valve body (13).

3. The device according to claim 1, characterized in that The slide rail (6) further comprises an upper ball (61), a lower ball (62) and a retaining frame (63). The upper ball (61) and the lower ball (62) are in close contact with the upper surface and the lower surface of the outer edge of the cam 5 respectively; the retaining frame (63) is used to constrain the positions of the upper ball (61) and the lower ball (62), and is fixedly connected to the connecting rod (8).

4. The device according to claim 1, characterized in that The cam (5) is of an axisymmetric shape.

5. The device according to claim 2, characterized in that The valve stem (10) is printed with scales for indicating the moving position of the valve core (12).

6. A method for generating a high-frequency hydraulic pulsation signal based on a cam profile design, characterized in that: Use any device as described in claims 2-5 to output a hydraulic pulsation signal.

7. The method according to claim 6, characterized in that The system pressure is set by adjusting the position of the valve stem (10).

8. The method according to claim 7, characterized in that The hydraulic pulsation signal required by the tested product is discretized, and the position of the valve stem (10) corresponding to each hydraulic pulsation signal can be obtained according to the test, and the size of the cam can be calculated.

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