A cylinder body of a hydraulic breaker

Abstract

This invention discloses a hydraulic breaker cylinder body, relating to the field of hydraulic breaker technology. It includes a front cylinder body, a middle cylinder body, a rear cylinder body, and a reversing valve block, as well as a heat dissipation mechanism for cooling the middle cylinder body. The piston chamber of the middle cylinder body has a high-pressure chamber and a low-pressure chamber on its inner wall. The reversing valve block is connected to the high-pressure chamber via an oil inlet pipe one, and to the low-pressure chamber via an oil inlet pipe two. The heat dissipation mechanism includes a gasket fixedly connected to the lower end of the reversing valve block. A cooling channel is formed within the gasket. Both oil inlet pipe one and oil inlet pipe two are connected to the cooling channel via branch pipes. The cooling channel is connected to the excavator main unit via a return pipe. An oil outlet channel is formed within the gasket. This invention, through a split-type oil circuit design, externalizes the complex reversing valve block and oil circuit, connecting it to the middle cylinder body via pipelines, fundamentally eliminating the main throttling heat source inside the cylinder body.

Description

Technical Field

[0001] This invention relates to the field of hydraulic breakers, and more particularly to a cylinder body for a hydraulic breaker. Background Technology

[0002] As a core accessory of construction machinery, the performance and reliability of hydraulic breakers directly depend on the working state of the central cylinder, which is the heart of the breaker.

[0003] Chinese invention patent CN116892225B discloses a hydraulic breaker body, including an upper cylinder assembly and a through bolt assembly. A middle cylinder assembly is located at the bottom of the upper cylinder assembly, and a lower cylinder assembly is located at the end of the middle cylinder assembly away from the upper cylinder assembly. The upper, middle, and lower cylinder assemblies are detachably connected via the through bolt assembly. A piston rod is movably mounted inside the middle cylinder assembly. A nitrogen chamber is located at the bottom of the upper cylinder assembly, and the top of the piston rod is movably sealed at one end of the nitrogen chamber. An oil passage is opened on one side of the middle cylinder assembly, and a steering valve chamber is located in the middle section of the oil passage. A reversing valve is movably mounted inside the steering valve chamber. One side has an oil inlet and an oil outlet, and both the inlet and outlet are equipped with solenoid valves. The oil inlet end of the oil circuit is connected to the oil inlet, and the oil outlet end of the oil circuit is connected to the oil outlet, connecting the oil circuit to an external drive system. Hydraulic oil is introduced into the oil circuit, and the reversing valve changes the flow direction of the hydraulic oil in the oil circuit, driving the piston rod to reciprocate axially within the middle cylinder assembly. The top of the piston rod intermittently compresses the nitrogen in the nitrogen chamber. Through two design methods, the hydraulic breaker can adjust the striking frequency of the steel chisel based on the hardness of the object being acted upon, giving the hydraulic breaker extremely high crushing power, extremely low failure rate, extremely high stability, and extremely high durability. It is also more labor-saving, environmentally friendly, resource-saving, and extends the product's service life.

[0004] Based on the aforementioned existing technologies, the current mainstream cylinder block adopts an integrated design, where the complex pilot control oil circuit that controls the flow of hydraulic oil is directly cast or machined inside the cylinder block. The small, intersecting throttling oil circuits inside become the main heat source, and heat accumulates rapidly in the core area inside the cylinder block metal and is difficult to dissipate. This leads to excessively high local temperatures in the cylinder block, causing the material to soften, its hardness to decrease, and the seals to age rapidly. More seriously, the uneven temperature field generates huge thermal stress, which, when superimposed with the mechanical impact stress during operation, greatly accelerates the initiation and propagation of fatigue cracks in the cylinder block, becoming the main cause of early cracking failure of the cylinder block. In addition, the complex internal oil circuit channels are like drilling a large number of stress concentrators in the cylinder block, seriously damaging the structural integrity of the cylinder block as a thick-walled pressure-bearing cylinder. Under long-term high-frequency impact loads, these oil circuit corners and intersections are very likely to become the origin of fatigue cracks, reducing the overall load-bearing capacity and service life of the cylinder block. Summary of the Invention

[0005] To address the problems in the prior art, the present invention adopts the following technical solution:

[0006] A hydraulic breaker cylinder body includes a front cylinder body, a middle cylinder body, a rear cylinder body, and a reversing valve block, and also includes a heat dissipation mechanism for cooling the middle cylinder body.

[0007] The piston chamber of the middle cylinder is provided with a high-pressure chamber and a low-pressure chamber. The reversing valve block is connected to the high-pressure chamber through an oil inlet pipe 1 and to the low-pressure chamber through an oil inlet pipe 2.

[0008] The heat dissipation mechanism includes a gasket fixedly connected to the lower end of the reversing valve block. A cooling channel is formed inside the gasket. Both the first oil inlet pipe and the second oil inlet pipe are connected to the cooling channel through branch pipes. The cooling channel is connected to the excavator host through a return oil pipe. An oil outlet channel is formed inside the gasket. The high-pressure chamber and the low-pressure chamber are respectively connected to the oil outlet channel through oil outlet pipes. The oil outlet channel is connected to the return oil pipe through a connecting pipe.

[0009] Preferably, the upper end of the reversing valve block is fixedly connected to a connection port, which is used to fix the pump oil pipeline of the external main hydraulic pump.

[0010] Preferably, both the high-pressure chamber and the low-pressure chamber have signal feedback channels on their inner walls, and the signal feedback channels are connected to the reversing valve block through connecting pipes.

[0011] Preferably, a nitrogen chamber is provided in the front cylinder, and a piston rod is slidably connected to the inner wall of the piston chamber of the middle cylinder. The side wall of the piston rod is slidably connected to both the inner walls of the high-pressure chamber and the low-pressure chamber, and the side wall of the piston rod is slidably connected to the port of the nitrogen chamber.

[0012] Preferably, the front cylinder block, middle cylinder block, and rear cylinder block are fixedly connected by a plurality of long bolt assemblies.

[0013] Preferably, the gasket is made of a high thermal conductivity copper alloy material.

[0014] Preferably, the heat dissipation mechanism further includes a vacuum chamber formed in the liner, the vacuum chamber being filled with fluorinated liquid, the inner wall of the vacuum chamber being fixedly connected with multiple layers of wire mesh, and the bottom of the vacuum chamber being provided with multiple grooves.

[0015] Preferably, the wire mesh is made of stainless steel.

[0016] Preferably, a plurality of springs are fixedly connected to the lower end of the gasket, and an annular washer is fixedly connected to the lower end of each spring. A threaded rod is threadedly connected to the inner wall of the annular washer, and the threaded rod passes through the gasket and the spring. A plurality of T-shaped threaded holes that mate with the threaded rod are opened at the upper end of the middle cylinder.

[0017] Preferably, a plurality of SMA springs are fixedly connected to the lower end of the pad, and the other end of each SMA spring is fixedly connected to an annular washer.

[0018] The present invention has the following beneficial effects:

[0019] 1. By setting up a heat dissipation mechanism and using a split oil circuit design, the complex reversing valve block and oil circuit are placed externally and connected to the cylinder block through pipelines, which fundamentally eliminates the main throttling heat source inside the cylinder block. Furthermore, a vacuum chamber gasket containing a phase change working fluid and a capillary suction core is set between the cylinder block and the reversing valve block. Utilizing the principles of working fluid vaporization, condensation circulation, and capillary pumping, the local hot spot heat on the surface of the cylinder block is instantly diffused to the entire gasket surface, and then efficiently carried away by the cooling oil flowing through the gasket. The efficiency of this phase change heat transfer method far exceeds that of traditional solid heat conduction, significantly reducing the maximum operating temperature of the cylinder block and the internal temperature difference, and effectively suppressing material softening and the generation of thermal stress cracks.

[0020] 2. With the adoption of a split design, the interior of the middle cylinder is greatly simplified, retaining only the main piston chamber and the necessary signal feedback channel, making it a robust load-bearing component with a complete structure that is close to an ideal thick-walled cylinder. This avoids the stress concentration effect caused by internal cross oil circuits, significantly improves the overall structural strength, reduces the risk of deformation of the middle cylinder when subjected to ultra-high impact loads, and significantly improves fatigue resistance, ensuring the reliability of the equipment under heavy impact.

[0021] 3. By setting springs and SMA springs, intelligent dynamic adjustment of the clamping force of the mating surface is realized. Under normal working conditions, the system is in flexible mode, which ensures the seal with the basic pre-tightening force while allowing a certain degree of flexible deformation to absorb vibration and displacement, effectively preventing fretting wear and thread rod overload. Under heavy-load conditions, the SMA spring undergoes a phase change when heated, and its stiffness and restoring force increase sharply, actively and significantly enhancing the clamping force of the mating surface. It can automatically compensate for the creep of the thread rod, material relaxation and separation force generated by high pressure oil caused by high temperature, ensuring absolute reliability of the seal and stable connection under extreme working conditions.

[0022] 4. The reversing valve block is externally mounted, and can be independently removed for repair or replacement in case of failure, without replacing the entire cylinder block assembly. This significantly reduces repair time and costs. By replacing the reversing valve block with different performance parameters, the performance of the hydraulic breaker can be easily upgraded or adapted to different working conditions. Attached Figure Description

[0023] Figure 1This is a schematic diagram of the cylinder body in a hydraulic breaker proposed in this invention;

[0024] Figure 2 for Figure 1 Cross-sectional view of the middle structure;

[0025] Figure 3 for Figure 2 Enlarged schematic diagram of the structure at point A in the diagram;

[0026] Figure 4 for Figure 1 Schematic diagram of the structure of the reversing valve block;

[0027] Figure 5 for Figure 1 A schematic diagram of the transverse cross-sectional structure of the middle liner;

[0028] Figure 6 for Figure 5 A cross-sectional view of the middle liner from another angle;

[0029] Figure 7 for Figure 1 A schematic diagram of the vertical cross-sectional structure of the middle liner;

[0030] Figure 8 for Figure 7 Enlarged schematic diagram of the structure at point B in the diagram;

[0031] Figure 9 for Figure 1 Schematic diagram of the cross-sectional structure of the middle cylinder block;

[0032] Figure 10 for Figure 9 A magnified schematic diagram of the structure at point C.

[0033] In the diagram: 1. Front cylinder block; 2. Middle cylinder block; 3. Rear cylinder block; 4. Reversing valve block; 5. Gasket; 6. High-pressure chamber; 7. Low-pressure chamber; 8. Oil inlet pipe one; 9. Oil inlet pipe two; 10. Cooling channel; 11. Branch pipe; 12. Return pipe; 13. Oil outlet channel; 14. Oil outlet pipe; 15. Connecting pipe; 16. Vacuum chamber; 17. Wire mesh; 18. Groove; 19. Annular gasket; 20. Threaded rod; 21. T-shaped threaded hole; 22. Spring; 23. SMA spring; 24. Signal feedback channel; 25. Connecting pipe; 26. Nitrogen chamber; 27. Piston rod; 28. Long bolt assembly; 29. ​​Connection port. Detailed Implementation

[0034] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below. Example 1

[0035] Reference Figures 1-6 A hydraulic breaker cylinder body includes a front cylinder body 1, a middle cylinder body 2, a rear cylinder body 3, and a reversing valve block 4, and also includes a heat dissipation mechanism for cooling the middle cylinder body 2.

[0036] It should be noted that the directional valve block 4, i.e. the directional valve, can adjust and change the flow direction of hydraulic oil. This is existing technology and will not be elaborated here.

[0037] The piston chamber of the middle cylinder 2 has a high-pressure chamber 6 and a low-pressure chamber 7. The reversing valve block 4 is connected to the high-pressure chamber 6 through the first oil inlet pipe 8, and the reversing valve block 4 is connected to the low-pressure chamber 7 through the second oil inlet pipe 9.

[0038] The heat dissipation mechanism includes a gasket 5 fixedly connected to the lower end of the reversing valve block 4. The gasket 5 is made of high thermal conductivity copper alloy material. A cooling channel 10 is opened in the gasket 5. The first oil inlet pipe 8 and the second oil inlet pipe 9 are both connected to the cooling channel 10 through the branch pipe 11. The cooling channel 10 is connected to the excavator host through the return oil pipe 12. An oil outlet channel 13 is opened in the gasket 5. The high pressure chamber 6 and the low pressure chamber 7 are respectively connected to the oil outlet channel 13 through the oil outlet pipe 14. The oil outlet channel 13 is connected to the return oil pipe 12 through the connecting pipe 15.

[0039] The upper end of the reversing valve block 4 is fixedly connected to a connection port 29, which is used to fix the pump oil pipeline of the external main hydraulic pump.

[0040] Both the high-pressure chamber 6 and the low-pressure chamber 7 have signal feedback channels 24 on their inner walls, and the signal feedback channels 24 are connected to the reversing valve block 4 through the connecting pipe 25.

[0041] A nitrogen chamber 26 is provided in the front cylinder block 1. A piston rod 27 is slidably connected to the inner wall of the piston chamber of the middle cylinder block 2. The side wall of the piston rod 27 is slidably connected to the inner wall of the high pressure chamber 6 and the low pressure chamber 7, and the side wall of the piston rod 27 is slidably connected to the port of the nitrogen chamber 26.

[0042] The front cylinder block 1, the middle cylinder block 2, and the rear cylinder block 3 are fixedly connected by a series of long bolts 28.

[0043] Furthermore, the excavator engine drives the main hydraulic pump to operate, pumping hydraulic oil from the tank into the reversing valve block 4 through the pump oil pipeline. Then, the hydraulic oil enters the low-pressure chamber 7 through the oil inlet pipe 29. At this time, the hydraulic oil injected into the low-pressure chamber 7 pushes the piston rod 27 to slide towards the front cylinder block 1. Meanwhile, the hydraulic oil in the high-pressure chamber 6 is squeezed out through the oil outlet pipe 14. As the piston rod 27 slides, it simultaneously squeezes the nitrogen in the nitrogen chamber 26. The nitrogen is compressed and stored. When the piston rod 27 moves to the top dead center, the signal feedback channel 24 in the high-pressure chamber 6 is blocked, thereby changing the signal in the connecting pipe 25 connected to it. When the oil pressure triggers a reversing signal, the reversing valve block 4 pumps hydraulic oil into the high-pressure chamber 6 through the oil inlet pipe 8, pushing the piston rod 27 to move towards the rear cylinder 3. The stored nitrogen also provides a strong thrust, causing the piston rod 27 to move rapidly and strike the steel chisel in the rear cylinder 3, thereby generating a strong impact force on the breaker. When the signal feedback channel 24 in the low-pressure chamber 7 is blocked, a reversing signal is triggered. At this time, the piston rod 27 moves towards the front cylinder 1 to store energy. This process repeats, with the piston rod 27 continuously moving back and forth to strike the steel chisel, thus impacting the breaker and achieving crushing.

[0044] Furthermore, the reciprocating sliding of the piston rod 27 generates intense friction with the cylinder block 2, causing the temperature of the cylinder block 2 to rise rapidly. The hydraulic oil also generates throttling heat, resulting in excessively high local temperatures in the cylinder block 2, leading to material softening and decreased hardness. More seriously, the uneven temperature field generates thermal stress, which, combined with mechanical stress, accelerates fatigue and deformation. Since the gasket 5 is made of a highly thermally conductive copper alloy, the heat on the cylinder block 2 is quickly absorbed by the gasket 5. During hydraulic oil pumping, some cold hydraulic oil enters the cooling channel 10 through the branch pipe 11. The hydraulic oil flowing within the cooling channel 10 absorbs heat from the gasket 5. Then, the hydraulic oil in the cooling channel 10 flows back to the excavator main unit via the return pipe 12, where it is cooled by the radiator. This allows for recycling. Furthermore, the hydraulic oil in the high-pressure chamber 6 and low-pressure chamber 7 is discharged into the outlet channel 13 via the outlet pipe 14. Flowing within the outlet channel 13, the heat from the hydraulic oil discharged from the high-pressure chamber 6 and low-pressure chamber 7 is absorbed by the gasket 5 and then by the cold hydraulic oil in the cooling channel 10. This process guides the hydraulic oil from the high-pressure chamber 6 and low-pressure chamber 7 out of the cylinder block 2 before further cooling. For cooling, compared to existing technologies, the pilot control oil circuit for switching high-pressure oil circuits is directly cast or machined inside the cylinder block 2. When hydraulic oil flows through these tiny channels, it generates intense throttling heat, which accumulates directly in the core area of ​​the cylinder block 2 and is difficult to dissipate. In contrast, this device centrally positions the reversing valve block 4, inlet pipe, and outlet pipe on the outer side wall of the cylinder block 2. The cylinder block 2 only has a piston chamber for piston rod 27 sliding and a signal feedback channel 24 inside. This fundamentally eliminates the tiny, intersecting throttling oil circuits, cuts off the main heat source inside the cylinder block 2, and makes the temperature field of the cylinder block 2 more... The uniformity of the design eliminates the enormous thermal stress caused by localized high temperatures, extending the lifespan of the cylinder block 2 under high-cycle fatigue loads. In addition, the complex internal cross-oil circuits in existing technologies are like drilling countless stress concentration holes in the cylinder block 2, severely weakening its overall structural strength and becoming the origin of fatigue cracks under high-pressure impact. In contrast, this device adopts a split structure, making the cylinder block 2 a more complete and robust component that is closer to an ideal thick-walled cylinder. The mechanical load-bearing capacity is greatly improved, and it can withstand ultra-high impact loads. Especially when performing extreme tests such as plastic zone calibration, the risk of deformation is reduced, and the data is more reliable. Example 2

[0045] Reference Figures 7-8 The heat dissipation mechanism also includes a vacuum chamber 16 opened in the liner 5. The vacuum chamber 16 is filled with fluorinated liquid, which is FC-72 with a boiling point of 56 degrees Celsius. Multiple layers of wire mesh 17 are fixedly connected to the inner wall of the vacuum chamber 16. Multiple grooves 18 are opened at the bottom of the vacuum chamber 16. The grooves 18 are at the micron level and can be manufactured by etching or precision machining technology.

[0046] The wire mesh 17 is made of stainless steel. The multiple layers of wire mesh 17 are stacked and covered. The bottom layer of wire mesh 17 and the top layer of wire mesh 17 are fused to the bottom and top surfaces of the vacuum cavity 16, respectively. The pore size of the wire mesh 17 increases from the bottom to the top surface of the vacuum cavity 16, and the pore size of the wire mesh 17 is all at the micron level.

[0047] Furthermore, the heat from the hydraulic oil in the cylinder block 2 and the oil outlet channel 13 is preferentially absorbed by the lower end of the gasket 5, and then the heat is transferred upwards. At this time, the fluorinated liquid in the vacuum chamber 16 absorbs heat and vaporizes rapidly. The pressure at the lower end of the vacuum chamber 16 is slightly higher than the pressure at the upper end. Since the inside of the vacuum chamber 16 is a vacuum, there are almost no other non-condensable gases besides the fluorinated liquid vapor, resulting in extremely low flow resistance. Consequently, under the action of the pressure difference, the fluorinated liquid vapor diffuses to the entire upper end of the vacuum chamber 16 at an extremely fast speed. The rapid diffusion of the fluorinated liquid vapor makes the temperature of the entire vacuum chamber 16 high. The uniformity of heat distribution allows the heat from localized hot spots to be instantly distributed across the entire area of ​​the liner 5. When the fluorinated liquid vapor comes into contact with the upper surface of the vacuum chamber 16, the heat from the vapor is absorbed by the cooling hydraulic oil within the cooling channel 10, as the upper surface of the vacuum chamber 16 is adjacent to the cooling channel 10. Consequently, the fluorinated liquid vapor condenses into droplets on the upper surface of the vacuum chamber 16. These droplets wet the wire mesh 17 at the upper surface of the vacuum chamber 16, forming a concave meniscus at the tiny pore entrance of the wire mesh 17. This concave meniscus generates an additional pressure difference, i.e., capillary pressure. Furthermore, due to the pressure difference between the lower and upper surfaces of the vacuum chamber 16... The mesh size of the wire mesh 17 increases progressively, thus the capillary pressure from the upper to the lower end of the vacuum chamber 16 increases progressively. Under this gradient capillary pressure, the fluorinated liquid droplets condensing on the upper end of the vacuum chamber 16 flow downwards within the mesh size of the wire mesh 17, reaching the edge of the groove 18. Because the flow resistance of the liquid is high at the mesh size of the wire mesh 17, when it reaches the edge of the groove 18, the cross-sectional area of ​​the groove 18 is much larger than the mesh size of the wire mesh 17. At this point, the flow resistance within the groove 18 is very low, and the fluorinated liquid droplets quickly flow to the evaporation point on the lower end of the vacuum chamber 16, continuing to absorb heat and vaporize. This cycle repeats. This heat dissipation method has several advantages. First, the vapor diffusion rate is extremely fast, keeping the entire vacuum chamber 16 almost isothermal. This effectively alleviates material softening and thermal stress concentration caused by localized high temperatures, thereby inhibiting crack formation. Second, phase change heat transfer relies on latent heat, which is far more efficient than sensible heat conduction that relies on temperature differences. The vapor diffusion rate is close to the speed of sound, allowing heat to be transferred from the heat source to the cold end at the fastest speed, further improving heat dissipation efficiency. Finally, the entire cycle drive force and return flow power are directly derived from the heat input itself, resulting in no wear and an extremely long service life. This makes it particularly suitable for harsh environments with high vibration and high impact, such as hydraulic breakers. Example 3

[0048] Reference Figures 9-10The lower end of the gasket 5 is fixedly connected to multiple springs 22, and the lower end of each spring 22 is fixedly connected to an annular washer 19. The inner wall of the annular washer 19 is threaded with a threaded rod 20, and the threaded rod 20 passes through the gasket 5 and the spring 22. The upper end of the middle cylinder 2 is provided with multiple T-shaped threaded holes 21 that cooperate with the threaded rod 20.

[0049] Multiple SMA springs 23 are fixedly connected to the lower end of the pad 5, and the other end of each SMA spring 23 is fixedly connected to the annular washer 19.

[0050] It should be noted that the SMA spring 23 is specially trained to be softer when the temperature is below 50 degrees Celsius and to undergo a phase change when the temperature is above 60 degrees Celsius.

[0051] Furthermore, during installation of the gasket 5 and the reversing valve block 4, the annular gasket 19 and the threaded rod 20 are placed into the T-shaped threaded hole 21, and then the threaded rod 20 is rotated so that it screws into the T-shaped threaded hole 21. At this time, the threaded rod 20 will press down on the gasket 5 to fit against the surface of the cylinder body 2, and the springs 22 and SMA springs 23 will be compressed and contracted synchronously. The spring 22 can provide initial preload and flexible support. When the hydraulic breaker is under normal operating conditions, the temperature of the cylinder body 2 will decrease, and the heat transferred to the gasket 5 will also be lower, thus reducing the heat transfer to the SMA spring. Spring 23 is in the martensitic phase. At this time, most of the preload is borne by spring 22, which has high stiffness and stable performance, providing a reliable and constant initial preload force to ensure the sealing of the mating surfaces of gasket 5 and cylinder 2 under cold and normal operating conditions. Since the stiffness contributed by SMA spring 23 is very small, the equivalent stiffness of the entire connection pair is low. When cylinder 2 undergoes slight elastic deformation due to pressure impact or when there is a difference in thermal expansion, it can absorb these displacements through flexible deformation, avoiding the generation of huge additional stress and effectively preventing fretting wear and overload of threaded rod 20.

[0052] When the hydraulic breaker is under heavy-load continuous operation, the temperature of the cylinder 2 will continue to rise due to the continuous heavy load, and more heat will be transferred to the liner 5, acting on the SMA spring 23. At this time, the SMA spring 23 undergoes a martensitic to austenitic phase transformation. When the SMA spring 23 attempts to recover its original length after the phase transformation, its elongation deformation is suppressed because its two ends are constrained by the liner 5 and the mounting point of the cylinder 2 fixed by the annular washer 19 and the threaded rod 20, respectively. This constrained restoring force is converted into a huge thrust on the annular washer 19 and the liner 5, which increases the tension of the threaded rod 20 to resist the separation tendency of the SMA spring 23. The increase in the tension of the threaded rod 20 directly means that it will separate the liner 5 and the annular washer 20. The plate 19 is pulled tighter, and since the spring 22 is connected in parallel with it, this tension is equivalent to further compressing the spring 22. As a result, the total clamping force applied by the entire fastening system to the mating surface of the gasket 5 and the middle cylinder 2 increases sharply. Because at high temperatures, the threaded rod 20 may creep and loosen, and the middle cylinder 2 and the gasket 5 may also yield slightly. The huge additional clamping force generated by the SMA spring 23 actively and instantly compensates for the preload loss caused by these factors. Moreover, the phase change of the SMA spring 23 is a process that is completed within a narrow temperature range, accompanied by a huge performance jump. This allows the system pressure to switch quickly and significantly between two optimal preset values, respectively adapting to the two completely different core requirements of cold-state anti-loosening and anti-wear and hot-state high-pressure sealing.

[0053] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A hydraulic breaker cylinder body, comprising a front cylinder body (1), a middle cylinder body (2), a rear cylinder body (3), and a reversing valve block (4), characterized in that, It also includes a heat dissipation mechanism for cooling the middle cylinder block (2); The piston chamber of the cylinder block (2) has a high-pressure chamber (6) and a low-pressure chamber (7) on its inner wall. The reversing valve block (4) is connected to the high-pressure chamber (6) through an oil inlet pipe (8) and to the low-pressure chamber (7) through an oil inlet pipe (9). The heat dissipation mechanism includes a gasket (5) fixedly connected to the lower end of the reversing valve block (4). A cooling channel (10) is provided in the gasket (5). The first oil inlet pipe (8) and the second oil inlet pipe (9) are connected to the cooling channel (10) through a branch pipe (11). The cooling channel (10) is connected to the excavator host through a return oil pipe (12). An oil outlet channel (13) is provided in the gasket (5). The high pressure chamber (6) and the low pressure chamber (7) are connected to the oil outlet channel (13) through an oil outlet pipe (14). The oil outlet channel (13) is connected to the return oil pipe (12) through a connecting pipe (15).

2. The cylinder body of a hydraulic breaker according to claim 1, characterized in that, The upper end of the reversing valve block (4) is fixedly connected to a connection port (29), which is used to fix the pump oil pipeline of the external main hydraulic pump.

3. The cylinder body of a hydraulic breaker according to claim 2, characterized in that, The inner walls of both the high-pressure chamber (6) and the low-pressure chamber (7) are provided with signal feedback channels (24), and the signal feedback channels (24) are connected to the reversing valve block (4) through the connecting pipe (25).

4. The cylinder body of a hydraulic breaker according to claim 3, characterized in that, The front cylinder (1) has a nitrogen chamber (26) inside. The piston chamber of the middle cylinder (2) is sealed and slidably connected to a piston rod (27). The side wall of the piston rod (27) is sealed and slidably connected to the inner walls of the high-pressure chamber (6) and the low-pressure chamber (7), and the side wall of the piston rod (27) is sealed and slidably connected to the port of the nitrogen chamber (26).

5. The cylinder body of a hydraulic breaker according to claim 4, characterized in that, The front cylinder block (1), the middle cylinder block (2) and the rear cylinder block (3) are fixedly connected by a plurality of long bolt assemblies (28).

6. The cylinder body of a hydraulic breaker according to claim 5, characterized in that, The gasket (5) is made of a high thermal conductivity copper alloy material.

7. The cylinder body of a hydraulic breaker according to claim 1, characterized in that, The heat dissipation mechanism also includes a vacuum chamber (16) opened in the liner (5), the vacuum chamber (16) is filled with fluorinated liquid, the inner wall of the vacuum chamber (16) is fixedly connected with multiple layers of wire mesh (17), and multiple grooves (18) are opened at the bottom of the vacuum chamber (16).

8. The cylinder body of a hydraulic breaker according to claim 7, characterized in that, The wire mesh (17) is made of stainless steel.

9. The cylinder body of a hydraulic breaker according to claim 1, characterized in that, The lower end of the liner (5) is fixedly connected to a plurality of springs (22), and the lower end of each spring (22) is fixedly connected to an annular washer (19). The inner wall of the annular washer (19) is threadedly connected to a threaded rod (20), and the threaded rod (20) passes through the liner (5) and the spring (22). The upper end of the middle cylinder (2) is provided with a plurality of T-shaped threaded holes (21) that cooperate with the threaded rod (20).

10. The cylinder body of a hydraulic breaker according to claim 9, characterized in that, The lower end of the pad (5) is fixedly connected to a plurality of SMA springs (23), and the other end of each SMA spring (23) is fixedly connected to an annular washer (19).

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