A hydraulic expansion coupling cavity pressure measurement system

Abstract

The present invention belongs to the technical field of couplings, and specifically relates to a hydraulic expansion coupling cavity pressure measurement system, including an inner sleeve, an outer sleeve, an oil storage cavity, a through hole, a pressure sensor, and a plug. The oil storage cavity is located between the inner sleeve and the outer sleeve, and pressure is applied to the inner sleeve by hydraulic oil so that the inner sleeve hugs the transmission shaft. The through hole is provided on the outer sleeve and is connected to the oil storage cavity. The pressure sensor is installed in the through hole and is used to measure the liquid pressure in the oil storage cavity. The plug is installed on the outside of the through hole and is used to seal the mounting interface of the pressure sensor. A distance is set between the sensing end face of the pressure sensor and the side of the oil storage cavity, and the pressure sensor also includes a protrusion block, and there are multiple protrusion blocks, and the multiple protrusion blocks are arranged on the outer surface of the inner sleeve in the oil storage cavity. The present invention suppresses the rotational flow of the hydraulic oil in the oil storage cavity through the protrusion block, reduces the interference of the dynamic pressure effect, improves the accuracy of the pressure measurement, and avoids misjudgment.

Description

Technical Field

[0001] The invention belongs to the technical field of couplings, and in particular relates to a pressure measuring system for a hydraulic expansion coupling cavity. Background Art

[0002] The hydraulic expansion coupling is an important component widely used in mechanical transmission. It applies pressure in the oil storage chamber through hydraulic oil to expand the inner sleeve and tightly hold the transmission shaft, thereby achieving efficient torque transmission and stable operation of the equipment. During the working process of the hydraulic expansion coupling, the liquid pressure in the oil storage chamber is an important parameter that determines the stability and safety of the system operation, so accurate measurement of the liquid pressure is crucial.

[0003] However, during the actual operation of the coupling, especially when the pressure in the oil storage chamber decreases, due to the high-speed rotation of the coupling, the hydraulic oil in the oil storage chamber is affected by the centrifugal force and may rotate with the chamber. This liquid rotation phenomenon will cause the generation of dynamic pressure effect, so that the pressure measured by the pressure sensor contains a dynamic pressure component and cannot fully reflect the true static pressure in the oil storage chamber. In addition, when the pressure in the oil storage chamber decreases, the flow rate and centrifugal force effect of the hydraulic oil are significantly enhanced, further amplifying the interference of dynamic pressure on the measurement results, and ultimately causing the pressure sensor measurement value to be lower than the true static pressure in the oil storage chamber.

[0004] Due to misjudgment of pressure, operators may fail to detect system abnormalities in time, which may lead to equipment failure or mechanical damage. In high-load and high-speed scenarios, loose couplings caused by insufficient tightening force may pose a serious safety threat to personnel and equipment.

[0005] In the prior art, the problem of inaccurate pressure measurement of hydraulic expansion couplings is mainly solved by optimizing the sensitivity of the pressure sensor or adjusting the viscosity of the hydraulic oil. However, these methods can only improve the measurement accuracy under static or low-speed conditions. When the coupling rotates at high speed or the pressure in the oil storage chamber decreases, the influence of the dynamic pressure effect is still significant and difficult to completely eliminate.

[0006] Therefore, an effective technical solution is urgently needed to ensure that the pressure sensor can more accurately reflect the actual static pressure in the oil storage chamber when the pressure in the oil storage chamber of the hydraulic expansion coupling decreases, thereby ensuring the stable operation of the coupling and the safety of the system. Summary of the invention

[0007] In order to solve the above problems, the present invention provides a hydraulic expansion coupling cavity pressure measurement system, including an inner sleeve, an outer sleeve, an oil storage chamber, a through hole, a pressure sensor, and a plug. The oil storage chamber is located between the inner sleeve and the outer sleeve, and pressure is applied to the inner sleeve by hydraulic oil so that the inner sleeve holds the transmission shaft tightly. The through hole is provided on the outer sleeve and is connected to the oil storage chamber. The pressure sensor is installed in the through hole to measure the liquid pressure in the oil storage chamber. The plug is installed on the outside of the through hole to seal the installation interface of the pressure sensor. The core of the present invention is that a distance is set between the sensing end face of the pressure sensor and the side of the oil storage chamber, and it also includes a protrusion block, and there are multiple protrusion blocks, and the multiple protrusion blocks are arranged on the outer surface of the inner sleeve in the oil storage chamber.

[0008] In the present invention, the raised blocks are arranged on the outer surface of the inner sleeve, which hinder the rotational flow of the hydraulic oil. When the rotating liquid contacts the raised blocks, the streamlines are disturbed and energy loss is generated, and the rotational speed of the liquid is reduced. In addition, a plurality of raised blocks are distributed in the oil storage chamber, which destroys the high-speed flow channel formed by the hydraulic oil in the oil storage chamber and reduces the enhancing effect of the centrifugal force on the liquid flow rate. Since the raised blocks reduce the rotational speed of the liquid, the dynamic pressure component of the hydraulic oil is significantly reduced, ensuring that the liquid pressure in the oil storage chamber is closer to the static pressure measured by the pressure sensor. In addition, the sensing end face of the pressure sensor is not directly exposed to the high-speed flow area of ​​the oil storage chamber, but maintains a certain distance from the side, thereby reducing the impact of the rotating fluid on the surface of the pressure sensor, extending the life of the pressure sensor, and enabling the pressure sensor to accurately measure the pressure for a longer period of time.

[0009] Furthermore, the material of the protrusion is stainless steel, titanium alloy or hardened steel. Stainless steel, titanium alloy and hardened steel materials have high strength and wear resistance, and can resist the erosion caused by the flow of hydraulic oil and the wear caused by the pressure change in the cavity for a long time. In particular, stainless steel and titanium alloy can be used in hydraulic oil for a long time without corrosion, thereby extending the service life of the protrusion. These materials can maintain a stable shape under high pressure environment and will not deform due to pressure or temperature changes.

[0010] Furthermore, the surface of the raised block is an outwardly convex arc. The arc surface design reduces the streamline separation during the flow of the liquid, reduces the turbulence effect, and ensures a smoother flow of the liquid. The arc design avoids the accelerated local wear of the sharp corners due to the scouring of the liquid, thereby extending the service life. In addition, the raised arc shape can effectively change the rotation direction of the liquid, further reducing the dynamic pressure effect.

[0011] Furthermore, along the circumferential direction of the inner sleeve, a plurality of protrusions are distributed. The plurality of protrusions distributed circumferentially can evenly disturb the rotational flow of the hydraulic oil, so that the fluid pressure is more evenly distributed in the entire oil storage cavity. The phenomenon of high-speed flow or low-speed stagnation in certain areas is reduced, ensuring that the measured value of the pressure sensor is closer to the actual pressure.

[0012] Furthermore, a plurality of protrusions are distributed along the transmission shaft direction. Arranging the protrusions along the transmission shaft direction can cover the entire length area of ​​the oil storage cavity, effectively limiting the rotational flow of the liquid at different axial positions, and avoiding the phenomenon of abnormal flow velocity or uneven pressure distribution in certain axial areas of the oil storage cavity due to the lack of protrusions.

[0013] Furthermore, along the transmission shaft, the protrusion is high in the middle of the oil storage chamber. The middle of the oil storage chamber is where the liquid rotates fastest, and increasing the height of the protrusion can more effectively suppress the rotational flow in the middle area. After the height of the middle protrusion is increased, the rotational flow rate is further reduced, reducing the interference of dynamic pressure on the measured value of the pressure sensor.

[0014] Furthermore, along the transmission shaft direction, in the middle of the oil storage chamber, the spacing between the protrusions is small. The arrangement of protrusions with small spacing can form a denser turbulence area, further reducing the rotation speed of the liquid. The local pressure deviation in the middle area of ​​the oil storage chamber is reduced to ensure that the inner sleeve expansion force is more uniform. In addition, this design also reduces dynamic pressure fluctuations by refining the flow rate control in the middle area, thereby improving the stability of the pressure sensor.

[0015] Furthermore, flexible particles are provided in the hydraulic oil. The flexible particles increase the viscosity and damping of the liquid, reduce the rotational velocity of the liquid, and weaken the dynamic pressure effect. In addition, the flexible particles form a microscopic network structure in the liquid, which can absorb and disperse the instantaneous fluctuations of the fluid pressure and improve the stability of the system.

[0016] Furthermore, the flexible particles are carbon nanotubes or graphene sheets. Carbon nanotubes and graphene sheets have excellent lubrication properties, which can reduce the friction between the hydraulic oil and the oil storage cavity wall and the inner sleeve, and reduce system wear. The high specific surface area and flexible network structure of these materials can effectively enhance the damping characteristics of the liquid and further inhibit high-speed flow. In addition, carbon nanotubes and graphene sheets can exist stably in hydraulic oil for a long time and are not prone to chemical degradation.

[0017] Furthermore, the mass fraction of the flexible particles in the hydraulic oil is 0.5%-1%. In other words, the concentration of the flexible particles is low. Low concentrations of flexible particles in the hydraulic oil will not significantly increase the viscosity of the liquid, maintaining the dynamic response performance of the hydraulic system. In addition, low-concentration particles are more evenly distributed, reducing local pressure anomalies or blockages caused by particle aggregation. While providing sufficient damping, low-concentration particles cause less wear on system components (such as the oil storage cavity wall, inner sleeve, etc.).

[0018] Beneficial effects of the present invention:

[0019] (1) The present invention uses the raised block to suppress the rotational flow of hydraulic oil in the oil storage chamber, reduce the interference of dynamic pressure effect, improve the accuracy of pressure measurement, and avoid misjudgment. By accurately measuring the pressure of the oil storage chamber, it is ensured that the inner sleeve provides sufficient expansion force to prevent the transmission shaft from loosening or slipping, thereby improving the operating reliability of the hydraulic expansion coupling under high load and high speed conditions.

[0020] (2) The present invention evens out the pressure distribution of the hydraulic oil in the oil storage chamber through the distribution design of the protrusions, reduces local pressure anomalies and flow rate fluctuations, improves the uniformity of the tightening force, and enhances the dynamic balance performance of the coupling.

[0021] (3) The present invention adds low-concentration flexible particles (such as carbon nanotubes or graphene sheets) to the hydraulic oil to enhance the damping properties of the liquid, reduce the flow rate and dynamic pressure effect, and reduce the interference of pressure fluctuations on the measurement. At the same time, the flexible particles have a lubricating effect, reduce system wear and extend the service life of components.

[0022] Based on the above beneficial effects, the present invention has good application prospects in the field of coupling technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The present invention is a schematic diagram of a pressure measurement system for a hydraulic expansion coupling cavity.

[0024] Figure 2 It is a schematic diagram of the oil storage chamber and the pressure sensor when no protrusion block is provided.

[0025] In the figure: 1, inner sleeve; 2, outer sleeve; 3, transmission shaft; 4, oil storage chamber; 5, through hole; 6, pressure sensor; 7, plug; 8, protrusion. DETAILED DESCRIPTION

[0026] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below with reference to the accompanying drawings and examples.

[0027] The present invention provides a hydraulic expansion coupling cavity pressure measurement system, such as Figure 1As shown, it includes an inner sleeve 1, an outer sleeve 2, an oil storage chamber 4, a through hole 5, a pressure sensor 6, a plug 7 and a plurality of protrusions 8. The inner sleeve 1 is made of high-strength alloy steel, and the outer sleeve 2 is made of stainless steel with excellent corrosion resistance. The two together form an oil storage chamber 4. The oil storage chamber 4 applies pressure to the inner sleeve 1 through hydraulic oil, so that the inner sleeve 1 expands and fits tightly against the transmission shaft 3 to achieve torque transmission. Flexible particles with a mass fraction of 0.5%-1% are added to the hydraulic oil. The flexible particles are selected from carbon nanotubes or graphene sheets with a particle size of 1-10 microns. The liquid flow rate and dynamic pressure effect are reduced by enhancing the damping performance, and the lubrication effect is used to reduce system wear. A plurality of raised blocks 8 are evenly distributed on the outer surface of the inner sleeve in the oil storage chamber 4. The material of the raised blocks 8 is stainless steel, titanium alloy or hardened steel, and the surface is an outward convex arc shape. The height of a single raised block is 1 / 5 of the thickness of the oil storage chamber. There are 8-12 raised blocks distributed circumferentially and 4-6 rows distributed along the transmission shaft 3. The height of the raised blocks 8 in the middle area gradually increases to 1.5 times, and the spacing gradually decreases to 0.6 times, so as to further suppress the rotational flow of the liquid and equalize the pressure distribution. The through hole 5 is precisely processed and located on the outer sleeve 2, connected to the middle of the oil storage chamber 4, and a high-precision static pressure sensor 6 is installed inside. The pressure sensor 6 has a measurement range of 0-10MPa, and its end face is kept at a distance of 3-5 mm from the side wall of the oil storage chamber 4 to form a buffer area to reduce the interference of fluid impact on the measurement. The plug 7 is connected by a threaded connection to seal the through hole 5 and fix the pressure sensor 6. The present invention combines the damping effect of the flexible particles with the turbulence function of the raised blocks to effectively reduce the dynamic pressure effect, improve the pressure measurement accuracy, and ensure the system operation stability and component service life.

[0028] To more clearly illustrate the core idea of ​​the present invention, please see Figure 2 . Figure 2 This is a schematic diagram of the oil storage chamber 4 and the pressure sensor 6 when the protrusion block 8 is not provided. Figure 2 In the figure, the pressure sensor 6 measures the pressure at point A, but what is actually needed is the static pressure at point B of the inner sleeve 1. Due to the dynamic pressure effect generated by the flow of liquid in the oil storage chamber 4 (perpendicular to the paper direction), the pressure value at point A includes the superposition of static pressure and dynamic pressure (according to Bernoulli's principle), so the measurement value of the pressure sensor 6 is too high and cannot accurately reflect the true static pressure at the inner sleeve 1. This measurement deviation may lead to a misjudgment of the actual pressure of the oil storage chamber 4, thereby affecting the expansion effect of the inner sleeve 1. The present invention effectively suppresses the rotational flow of the liquid and reduces the dynamic pressure effect by providing a protruding block 8 and adding flexible particles, thereby reducing the measurement deviation and improving the accuracy of pressure measurement.

[0029] The present invention sets the protrusion block 8 on one side of the inner sleeve 1 (rather than on the side of the outer sleeve 2), which can directly act on the main pressure action surface of the liquid, inhibit the rotational flow of the hydraulic oil along the surface of the inner sleeve 1, reduce the flow rate, and thus effectively weaken the dynamic pressure effect. The fluid pressure distribution in the oil storage chamber 4 is optimized, the liquid pressure is more uniform, and the interference with the measurement value of the pressure sensor 6 is reduced, thereby improving the accuracy of the static pressure measurement. At the same time, the protrusion block 8 further enhances the stability of the expansion force by improving the uniformity of the pressure on the inner sleeve 1, ensuring the close fit of the inner sleeve 1 to the transmission shaft, and achieving more reliable torque transmission.

[0030] Preferably, the material of the protruding block 8 is a material with high thermal stability, such as titanium alloy, to prevent thermal expansion or deformation caused by temperature changes. In addition, the surface of the protruding block 8 is provided with a thermal conductive coating, which accelerates local heat diffusion, maintains the temperature uniformity of the hydraulic oil around the protruding block 8, maintains its turbulence effect, and continuously suppresses the dynamic pressure effect.

[0031] Preferably, the middle part of the oil storage chamber 4 is designed as a narrow area, and the edges are slightly thickened, so as to improve the flow characteristics and pressure distribution of the hydraulic oil when the oil storage chamber 4 is at low pressure, and improve the accuracy of pressure measurement. The narrow design in the middle limits the flow velocity of the hydraulic oil in this area, reduces the dynamic pressure effect caused by the flow velocity, and makes the measurement value of the pressure sensor 6 mainly reflect the static pressure of the oil storage chamber 4, thereby reducing the measurement error; at the same time, the narrow area concentrates the liquid flow near the protrusion 8, enhances the turbulence effect, and further weakens the influence of the liquid rotation flow. The thickening of the edge area provides additional buffer space, homogenizes the pressure distribution of the hydraulic oil, and reduces the local turbulence caused by the boundary effect. In addition, the thick edge area can absorb instantaneous pressure fluctuations in the liquid flow, which helps to improve the dynamic stability of the entire system.

[0032] Preferably, a small buffer cavity is provided at the connection between the through hole 5 and the oil storage cavity 4, and the diameter of the buffer cavity is slightly larger than the diameter of the through hole 5, so as to form a buffer zone for the liquid pressure. The buffer cavity can reduce the flow rate of the liquid when it enters the through hole, so that the dynamic pressure effect of the fluid gradually decays, forming a more stable pressure area for the pressure sensor 6 to measure, thereby reducing the direct impact of the liquid turbulence on the pressure sensor 6, and ensuring that the measured value is closer to the real static pressure of the oil storage cavity 4.

[0033] More preferably, the through hole 5 is designed to be inclined at an angle of 30°-45° with the oil storage chamber 4, rather than being vertically connected. The inclination angle can guide the liquid to flow into the through hole in a more natural path, reduce the impact force when the fluid enters, and reduce the amplification effect of the sudden change in the liquid flow direction on the dynamic pressure effect. This design can make the liquid flow near the pressure sensor 6 more stable, the measurement environment more stable, and further improve the reading accuracy of the pressure sensor 6.

[0034] The structure of the present invention can be realized by combining precision machining and assembly. The inner sleeve 1 and the outer sleeve 2 are formed by turning and inner and outer cylindrical grinding using high-strength metal materials, and ensure that a uniform oil storage chamber 4 is formed between the inner sleeve 1 and the outer sleeve 2; the middle part of the oil storage chamber 4 is thinned by precision machining to achieve a narrow design, and the edge area is slightly thickened to equalize the pressure. The raised block 8 can be formed directly on the outer surface of the inner sleeve by CNC milling or electrospark machining, and the surface is polished or coated to enhance wear resistance and thermal stability. The through hole 5 is formed by CNC drilling, and high-precision tapping is used to ensure a tight and reliable threaded connection with the pressure sensor 6 and the plug 7. The flexible particles can be dispersed and evenly mixed by ultrasonic waves during the hydraulic oil preparation process and then injected into the oil storage chamber 4, and finally the processing and assembly of the entire system are completed through precision assembly and sealing testing.

[0035] When using the present invention, the hydraulic expansion coupling is installed in the shaft system that needs to transmit torque. After ensuring that the inner sleeve 1 and the transmission shaft 3 are initially matched, the hydraulic oil containing flexible particles is injected into the oil storage chamber 4 through the hydraulic system, so that the pressure in the oil storage chamber 4 acts on the inner sleeve 1, causing it to expand and firmly hold the transmission shaft 3. When the coupling is started, the protrusion block 8 effectively suppresses the rotational flow of the liquid in the oil storage chamber 4, reduces the interference of the dynamic pressure effect on the pressure measurement, and the pressure sensor 6 monitors the static pressure in the oil storage chamber 4 in real time, and transmits the signal to the control system for the regulation of the operating state.

[0036] When maintaining the present invention, the cleanliness of the hydraulic oil and the dispersion state of the flexible particles should be checked regularly, and the aged hydraulic oil should be replaced or the dispersed particles should be added again in time; the surface of the protrusion block 8 should be checked for wear or deformation, and repaired or replaced if necessary to maintain its flow disturbance function. At the same time, the oil storage chamber 4 should be ensured to be well sealed, and the connection between the pressure sensor 6 and the plug 7 should be cleaned to prevent measurement errors or hydraulic oil leakage, so as to ensure stable operation of the system.

[0037] In summary, the present invention provides a hydraulic expansion coupling with a pressure measurement function. Through innovative designs such as adding flexible particles in the oil storage chamber 4, optimizing the structure and distribution of the protrusion block 8, and adjusting the geometric shape of the oil storage chamber 4, the interference of the dynamic pressure effect on the pressure measurement is significantly reduced, and higher pressure measurement accuracy is achieved. The present invention has broad application prospects in precision machinery, heavy equipment, and high-speed transmission systems. Especially in scenarios with high requirements for torque transmission stability and safety, it can improve system operation reliability and extend service life by real-time monitoring of the expansion force state. The significance of this invention is not only to improve the measurement accuracy of the hydraulic expansion coupling, but also to provide technical support for the intelligent monitoring and dynamic adjustment of the hydraulic system, and promote technological upgrading and precision improvement in the field of mechanical transmission.

[0038] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A hydraulic expansion coupling cavity pressure measurement system, comprising an inner sleeve, an outer sleeve, an oil storage cavity, a through hole, a pressure sensor, and a plug. The oil storage cavity is located between the inner sleeve and the outer sleeve. The inner sleeve is pressed against a transmission shaft by applying pressure to the inner sleeve through hydraulic oil. The through hole is provided on the outer sleeve and communicates with the oil storage cavity. The pressure sensor is installed in the through hole and is used to measure the liquid pressure in the oil storage cavity. The plug is installed outside the through hole and is used to seal the installation interface of the pressure sensor. The system is characterized in that: There is a certain distance between the sensing end face of the pressure sensor and the side wall of the oil storage cavity, and the pressure sensor also includes a protrusion block, and there are multiple protrusion blocks, and the multiple protrusion blocks are arranged on the outer surface of the inner sleeve in the oil storage cavity.

2. The hydraulic expansion coupling cavity pressure measurement system according to claim 1, characterized in that: The material of the protruding block is stainless steel, titanium alloy or hardened steel.

3. The hydraulic expansion coupling cavity pressure measurement system according to claim 1, characterized in that: The surface of the protruding block is in an outwardly convex arc shape.

4. The hydraulic expansion coupling cavity pressure measurement system according to claim 1, characterized in that: A plurality of the protruding blocks are distributed along the circumferential direction of the inner sleeve.

5. The hydraulic expansion coupling cavity pressure measurement system according to claim 1, characterized in that: There are a plurality of protrusions distributed along the transmission shaft.

6. The hydraulic expansion coupling cavity pressure measurement system according to claim 5, characterized in that: The height of the raised block in the middle of the oil storage cavity is greater than the height of the raised blocks in other areas of the oil storage cavity.

7. The hydraulic expansion coupling cavity pressure measurement system according to claim 5, characterized in that: In the middle of the oil storage cavity, the spacing between the protrusions is relatively small.

8. The hydraulic expansion coupling cavity pressure measurement system according to any one of claims 1 to 7, characterized in that: Flexible particles are arranged in the hydraulic oil.

9. The hydraulic expansion coupling cavity pressure measurement system according to claim 8, characterized in that: The flexible particles are carbon nanotubes or graphene sheets.

10. The hydraulic expansion coupling cavity pressure measurement system according to claim 9, characterized in that: The mass fraction of the flexible particles in the hydraulic oil is 0.5%-1%.

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