Middle cylinder assembly of anti-strain breaking hammer and hydraulic breaking hammer

Abstract

The invention belongs to the technical field of hydraulic breaking hammers, and provides an anti-strain breaking hammer middle cylinder assembly and a hydraulic breaking hammer, the anti-strain breaking hammer middle cylinder assembly comprises a cylinder body and a piston, the cylinder body is internally provided with an inner cavity, the inner cavity is divided into a middle cylinder intermediate diameter section and a middle cylinder small diameter section, and the diameter of the middle cylinder intermediate diameter section is larger than that of the middle cylinder small diameter section; the piston is divided into a piston middle section and a piston lower section, the diameter of the piston middle section is larger than that of the piston lower section, the piston middle section is in sliding fit with the middle-diameter section of the middle cylinder, and the piston lower section is in sliding fit with the small-diameter section of the middle cylinder. Wherein the inner wall of the middle-diameter section of the middle cylinder or the side wall of the middle section of the piston is a conical surface, the inner wall of the small-diameter section of the middle cylinder or the side wall of the lower section of the piston is a conical surface, and after the piston deflects under radial force, the side wall of the middle section of the piston is in linear contact with the inner wall of the middle-diameter section of the middle cylinder, and the side wall of the lower section of the piston is in linear contact with the inner wall of the small-diameter section of the middle cylinder. The hydraulic breaking hammer comprises the middle cylinder assembly of the anti-strain breaking hammer.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic breaker hammers, and in particular relates to a strain-proof breaker hammer cylinder assembly and a hydraulic breaker hammer. Background Art

[0002] A hydraulic breaker is an engineering equipment that uses hydraulic energy to drive and convert the pressure energy of hydraulic oil into mechanical impact energy. Its main function is to be installed at the arm end of engineering machinery such as excavators, and use the high-frequency impact force generated by its internal piston to drive the drill rod to violently impact hard and brittle materials such as rocks and concrete, thereby achieving efficient crushing, demolition or excavation operations. It is widely used in mining, construction, road maintenance and other fields.

[0003] Its core structure includes: a hydraulic system (high-pressure oil circuit and return oil circuit) that provides the power source, an impact mechanism (middle cylinder, piston, control valve) that converts hydraulic energy into reciprocating piston motion, a drill rod (working part) that directly transmits the impact force to the crushed object, a shell (front cylinder body, rear cylinder body) that accommodates the internal mechanism and provides an installation interface, and an accumulator (nitrogen chamber) for enhancing the impact force in some models. These components work together.

[0004] The piston slides back and forth in the middle cylinder, impacting the drill rod to break it. Currently, the piston and the middle cylinder are mainly lubricated by an oil film, which is prone to oil film failure, resulting in scratches on the piston or the middle cylinder. Summary of the Invention

[0005] The present invention provides a strain-proof breaker hammer cylinder assembly and a hydraulic breaker hammer, aiming to solve the technical problem that the cylinder assembly of the existing hydraulic breaker hammer is prone to oil film failure, which in turn causes scratches on the piston or the cylinder.

[0006] To achieve the above object, the present invention adopts the following technical solution: to provide an anti-strain breaker hammer cylinder assembly, comprising: In a first aspect, an embodiment of the present invention provides a strain-proof breaker hammer cylinder assembly, comprising: The cylinder body has an inner cavity, the inner cavity is divided into a middle diameter section of the middle cylinder and a small diameter section of the middle cylinder, the diameter of the middle diameter section of the middle cylinder is larger than the diameter of the small diameter section of the middle cylinder, and the small diameter section of the middle cylinder is arranged at the lower side of the middle diameter section of the middle cylinder; A piston is slidably disposed in the inner cavity, the piston being divided into a middle piston section and a lower piston section, the diameter of the middle piston section being larger than the diameter of the lower piston section, the middle piston section being in sliding engagement with the middle diameter section of the middle cylinder, and the lower piston section being in sliding engagement with the small diameter section of the middle cylinder; Among them, the inner wall of the middle diameter section of the middle cylinder or the side wall of the middle section of the piston is a conical surface, and the inner wall of the small diameter section of the middle cylinder or the side wall of the lower section of the piston is a conical surface. After the piston is deflected by radial force, the side wall of the middle section of the piston forms a line contact with the inner wall of the middle diameter section of the middle cylinder, and the side wall of the lower section of the piston forms a line contact with the inner wall of the small diameter section of the middle cylinder.

[0007] In combination with the first aspect, in a possible implementation of the anti-strain breaker hammer middle cylinder assembly provided by the present invention, the inner walls of the middle diameter section of the middle cylinder and the small diameter section of the middle cylinder are conical surfaces, and the diameter of the middle diameter section of the middle cylinder gradually decreases from top to bottom, and the diameter of the small diameter section of the middle cylinder gradually increases from top to bottom; the side wall of the piston is a cylindrical surface; after the piston is deflected by radial force, the side wall of the middle section of the piston forms a line contact with the inner wall of the middle diameter section of the middle cylinder, and the side wall of the lower section of the piston forms a line contact with the inner wall of the small diameter section of the middle cylinder.

[0008] In combination with the first aspect, in a possible implementation of the anti-strain breaker hammer cylinder assembly provided by the present invention, the inner walls of the middle diameter section of the middle cylinder and the small diameter section of the middle cylinder are cylindrical surfaces, the side walls of the middle section of the piston and the lower section of the piston are conical surfaces, and the diameter of the middle section of the piston gradually decreases from top to bottom, and the diameter of the lower section of the piston gradually increases from top to bottom; after the piston is deflected by radial force, the side wall of the middle section of the piston forms a line contact with the inner wall of the middle diameter section of the middle cylinder, and the side wall of the lower section of the piston forms a line contact with the inner wall of the small diameter section of the middle cylinder.

[0009] In combination with the first aspect, in a possible implementation of the anti-strain breaker hammer cylinder assembly provided by the present invention, the inner wall of the middle diameter section of the middle cylinder is a cylindrical surface, the inner wall of the small diameter section of the middle cylinder is a conical surface, and the diameter of the small diameter section of the middle cylinder gradually increases from top to bottom; the side wall of the middle section of the piston is a conical surface, the side wall of the lower section of the piston is a cylindrical surface, and the diameter of the middle section of the piston gradually increases from top to bottom; after the piston is deflected by radial force, the side wall of the middle section of the piston forms a line contact with the inner wall of the middle diameter section of the middle cylinder, and the side wall of the lower section of the piston forms a line contact with the inner wall of the small diameter section of the middle cylinder.

[0010] In combination with the first aspect, in a possible implementation of the cylinder assembly of the anti-strain breaker hammer provided by the present invention, the gap between the cylinder body and the piston is 0.06-0.15 mm.

[0011] In combination with the first aspect, in a possible implementation of the anti-strain breaker hammer middle cylinder assembly provided by the present invention, the sum of the tapers of the middle diameter section of the middle cylinder and the middle section of the piston is 0.000036~0.000056, and the sum of the tapers of the small diameter section of the middle cylinder and the lower section of the piston is 0.0001~0.00015.

[0012] In combination with the first aspect, in a possible implementation of the anti-strain breaker hammer cylinder assembly provided by the present invention, it also includes a molybdenum disulfide coating, which is coated on the inner wall of the inner cavity and has a thickness of 0.005~0.01mm.

[0013] In combination with the first aspect, in a possible implementation of the anti-strain breaker hammer cylinder assembly provided by the present invention, it also includes a transition layer, which is coated between the inner wall of the inner cavity and the molybdenum disulfide coating and has a thickness of 0.005~0.01mm.

[0014] In a second aspect, an embodiment of the present invention provides a hydraulic breaker hammer, comprising the above-mentioned anti-strain breaker hammer cylinder assembly.

[0015] The beneficial effects of the anti-strain hammer cylinder assembly and hydraulic breaker provided by the present invention are as follows: compared with the prior art, the anti-strain hammer cylinder assembly and hydraulic breaker provided by the present invention, in order to avoid damage to the piston caused by lateral offset force, break the traditional high-precision cylindricity thinking, and provide a cylinder body or piston with a taper. According to the deflection shape of the piston, the inner wall of the middle diameter section of the cylinder or the side wall of the middle section of the piston is processed into a conical surface, and the inner wall of the small diameter section of the cylinder or the side wall of the lower section of the piston is processed into a conical surface. In this way, after the piston is offset, the previous point contact is changed to line contact, which effectively reduces the local contact pressure, effectively reduces the probability of oil film damage, and thus effectively reduces the occurrence of strain. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic cross-sectional view of the cylinder assembly of an existing breaker hammer; Figure 2 A schematic cross-sectional view of a cylinder assembly of an anti-strain breaker hammer provided by an embodiment of the present invention; Description of reference numerals: 10. Cylinder body; 11. Inner cavity; 111. Middle diameter section of middle cylinder; 112. Small diameter section of middle cylinder; 12. Transition layer; 13. Molybdenum disulfide coating; 21. Piston middle section; 22. Piston lower section. DETAILED DESCRIPTION

[0017] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, this application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0018] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0019] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0020] Unless otherwise specified, the relative arrangement of the parts and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to actual proportional relationships. Technology, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments can have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, and therefore, once an item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0021] In the description of this application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of this application; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0022] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be subsequently positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device may also be positioned in other different ways, and the spatially relative descriptions used herein are interpreted accordingly.

[0023] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0024] The inner cavity and piston of the cylinder of the traditional hydraulic breaker are both cylindrical structures with equal diameters. The applicant found in the study of the scratch problem of the hydraulic breaker that Figure 1 As shown, the piston strikes the drill rod, which means that the striking plane of the piston hits the striking plane of the drill rod. There is usually a large gap between the inner and outer sleeves supporting the drill rod and the drill rod, especially the inner and outer sleeves after wear, the gap between them is even larger; during operation, the center line of the drill rod and the center line of the piston form an angle, and the striking point deviates from the center. In this case, when operating, the piston will generate a lateral component force F, the piston will deviate to the right, and the lower end of the piston will squeeze the right side of the cylinder body 10. The cylinder body 10 will generate a supporting force F1 on the lower section of the piston. Under the lever force, the middle section 21 of the piston will squeeze the left side of the cylinder body 10, and the cylinder body 10 will generate a force F2 on the middle section 21 of the piston. In the past, when the cylinder body 10 or piston components were processed, the cylindrical surfaces of the two components were controlled to a higher precision of cylindricity. When the piston deviates, point contact will be generated inside the cylinder body 10 (i.e. Figure 1 (The bold black dots in the figure indicate the contact areas; the contact areas are bolded for a more pronounced display effect). Locally generated high pressure can easily damage the oil film, leading to strain at the corresponding locations. To this end, the applicant developed the strain-resistant breaker cylinder assembly and hydraulic breaker provided by the present invention.

[0025] Please also refer to Figure 2The anti-strain hammer middle cylinder assembly provided by the present invention is now described. The anti-strain hammer middle cylinder assembly includes a cylinder body 10 and a piston. The cylinder body 10 is provided with an inner cavity 11. The inner cavity 11 is divided into a middle-diameter section 111 and a small-diameter section 112. The diameter of the middle-diameter section 111 is larger than the diameter of the small-diameter section 112. The small-diameter section 112 is provided below the middle-diameter section 111. The piston is slidably provided in the inner cavity 11. The piston is divided into a middle section 21 and a lower section 22. The diameter of the middle section 21 is larger than the diameter of the lower section 22. The middle section 21 slides with the middle-diameter section 111, and the lower section 22 slides with the small-diameter section 112.

[0026] Among them, the inner wall of the middle diameter section 111 of the middle cylinder or the side wall of the middle section 21 of the piston is a conical surface, and the inner wall of the small diameter section 112 of the middle cylinder or the side wall of the lower section 22 of the piston is a conical surface. After the piston is deflected by radial force, the side wall of the middle section 21 of the piston forms a line contact with the inner wall of the middle diameter section 111 of the middle cylinder, and the side wall of the lower section 22 of the piston forms a line contact with the inner wall of the small diameter section 112 of the middle cylinder.

[0027] The beneficial effect of the anti-strain breaker hammer cylinder assembly provided by the present invention is as follows: compared with the prior art, the anti-strain breaker hammer cylinder assembly provided by the present invention breaks the traditional high-precision cylindrical thinking in order to avoid damage to the piston caused by the lateral offset force, and sets a cylinder body 10 or a piston with a taper. According to the deflection shape of the piston, the inner wall of the middle diameter section 111 of the cylinder or the side wall of the middle section 21 of the piston is processed into a conical surface, and the inner wall of the small diameter section 112 of the cylinder or the side wall of the lower section 22 of the piston is processed into a conical surface. In this way, after the piston is offset, the previous point contact is changed to line contact (i.e. Figure 2 The position indicated by the bold line in the middle, in order to make the display effect more obvious, the contact part is displayed in bold), which effectively reduces the pressure in the contact area, effectively reduces the probability of oil film damage, and thus effectively reduces the occurrence of strain.

[0028] like Figure 2 As shown, in a specific embodiment of the anti-strain breaker hammer cylinder assembly provided by an embodiment of the present invention, the inner walls of the cylinder middle diameter section 111 and the cylinder small diameter section 112 are conical surfaces, and the diameter of the cylinder middle diameter section 111 gradually decreases from top to bottom, and the diameter of the cylinder small diameter section 112 gradually increases from top to bottom; the piston side wall is a cylindrical surface; after the piston is deflected by radial force, the side wall of the piston middle section 21 forms a line contact with the inner wall of the cylinder middle diameter section 111, and the side wall of the piston lower section 22 forms a line contact with the inner wall of the cylinder small diameter section 112.

[0029] It should be noted that in order to make the display effect more obvious, Figure 2 The taper of the middle cone is exaggerated, and the actual taper is much smaller than Figure 2 The taper shown in the figure is small.

[0030] In addition, in a specific embodiment of the anti-strain hammer middle cylinder assembly provided in an embodiment of the present invention, the inner walls of the middle cylinder middle diameter section 111 and the middle cylinder small diameter section 112 are cylindrical surfaces, the side walls of the piston middle section 21 and the piston lower section 22 are conical surfaces, and the diameter of the piston middle section 21 gradually decreases from top to bottom, and the diameter of the piston lower section 22 gradually increases from top to bottom; after the piston is deflected by radial force, the side wall of the piston middle section 21 forms a line contact with the inner wall of the middle cylinder middle diameter section 111, and the side wall of the piston lower section 22 forms a line contact with the inner wall of the small diameter section 112 of the middle cylinder.

[0031] In addition, in a specific embodiment of the anti-strain breaker hammer cylinder assembly provided in an embodiment of the present invention, the inner wall of the middle diameter section 111 of the middle cylinder is a cylindrical surface, the inner wall of the small diameter section 112 of the middle cylinder is a conical surface, and the diameter of the small diameter section 112 of the middle cylinder gradually increases from top to bottom; the side wall of the middle section 21 of the piston is a conical surface, the side wall of the lower section 22 of the piston is a cylindrical surface, and the diameter of the middle section of the piston gradually increases from top to bottom; after the piston is deflected by radial force, the side wall of the middle section 21 of the piston forms a line contact with the inner wall of the middle diameter section 111 of the middle cylinder, and the side wall of the lower section 22 of the piston forms a line contact with the inner wall of the small diameter section 112 of the middle cylinder.

[0032] It should be noted that the above three forms can all achieve the beneficial effect of less scratching. However, since the area length of the middle diameter section 111 of the middle cylinder is larger than the area of ​​the middle section 21 of the piston, and the area of ​​the small diameter section 112 of the middle cylinder is smaller than the side wall area of ​​the lower section 22 of the piston; therefore, in order to reduce the processing area, shorten the processing time, and reduce the processing difficulty, it is preferred to process the inner wall of the small diameter section 112 of the middle cylinder and the side wall of the middle section 21 of the piston into a conical surface.

[0033] It should be further explained that, in addition to the above three forms, the middle diameter section 111 of the middle cylinder, the small diameter section 112 of the middle cylinder, the middle section 21 of the piston and the lower section 22 of the piston can all be processed into conical surfaces; or the middle diameter section 111 of the middle cylinder and the lower section 22 of the piston can be processed into conical surfaces, and the small diameter section 112 of the middle cylinder and the middle section 21 of the piston can be processed into cylindrical surfaces, as long as the piston can form linear contact with the cylinder body after deflection.

[0034] When the piston deflects, its cylindrical surfaces (the middle and lower sections 21 and 22) form line contact with the corresponding conical inner walls of the cylinder block 10 (the middle and smaller diameter sections 111 and 112). Compared to point contact during conventional deflection, line contact significantly increases the contact area. This increased contact area offers a crucial advantage: it effectively reduces the local pressure at the contact point. This lower pressure significantly reduces the stress on the oil film in the contact area, making it less susceptible to collapse or damage. The continued presence of the oil film is essential for avoiding direct metal-to-metal contact and preventing surface damage.

[0035] like Figure 2As shown, in a specific embodiment of the anti-strain breaker hammer cylinder assembly provided by an embodiment of the present invention, the clearance between the cylinder body 10 and the piston is 0.06-0.15mm to ensure a balance between lubrication and sealing. A too small clearance may affect the flow of lubricating oil, resulting in insufficient lubrication, while also increasing manufacturing difficulty and sensitivity to impurities. A too large clearance can cause excessive hydraulic oil leakage (internal leakage) when there is no or little deflection, reducing the breaker's impact efficiency and potentially affecting the ambient pressure required to establish the oil film.

[0036] like Figure 2 As shown, in a specific implementation of the anti-strain breaker hammer middle cylinder assembly provided by an embodiment of the present invention, the sum of the tapers of the middle diameter section 111 of the middle cylinder and the middle section 21 of the piston is 0.000036-0.000056.

[0037] The sum of the tapers of the small diameter section 112 of the middle cylinder and the lower section 22 of the piston is 0.0001 to 0.00015.

[0038] Preferably, the sum of the tapers of the middle diameter section 111 of the middle cylinder and the middle section 21 of the piston is 0.000046, and the sum of the tapers of the small diameter section 112 of the middle cylinder and the lower section 22 of the piston is 0.000125.

[0039] Specifically, when the middle diameter section 111 of the cylinder is a cylindrical surface and the piston middle section 21 is a conical surface, the taper of the piston middle section 21 is 0.000046. When the middle diameter section 111 of the cylinder is a conical surface and the piston middle section 21 is a cylindrical surface, the taper of the taper of the middle diameter section 111 of the cylinder is 0.000046. When the small diameter section 112 of the cylinder is a conical surface and the piston lower section 22 is a cylindrical surface, the taper of the taper of the small diameter section 112 of the cylinder is 0.000125. When the small diameter section 112 of the cylinder is a cylindrical surface and the piston lower section 22 is a conical surface, the taper of the taper of the piston lower section 22 is 0.000125.

[0040] It should be noted that this slight taper ensures that when the piston undergoes radial deflection within a normal range, the piston side surface can accurately form a stable linear contact with the corresponding side surface of the inner cavity 11 of the cylinder body 10 .

[0041] like Figure 2 As shown, in a specific implementation of the anti-strain breaker hammer cylinder assembly provided by an embodiment of the present invention, it also includes a molybdenum disulfide coating 13, which is coated on the inner wall of the inner cavity 11 and has a thickness of 0.005~0.01mm.

[0042] like Figure 2 As shown, in a specific embodiment of the anti-strain breaker hammer cylinder assembly provided by an embodiment of the present invention, it also includes a transition layer 12, which is coated between the inner wall of the inner cavity 11 and the molybdenum disulfide coating 13, with a thickness of 0.005~0.01mm.

[0043] It should be noted that an existing surface treatment process is used to generate a transition layer 12 on the inner wall of the inner cavity 11 of the cylinder body 10 that has corrosion resistance and can improve surface adhesion, thereby improving surface adhesion while preventing corrosion. Then, a molybdenum disulfide coating 13 is coated on the surface of the transition layer 12 to provide good self-lubricating properties.

[0044] The transition layer 12 is a phosphating layer obtained by phosphating the surface, which has good corrosion resistance, can effectively increase the surface adhesion, and effectively prevent the molybdenum disulfide coating from falling off.

[0045] The transition layer 12 can also be a zinc-chromium coating, which is a new type of anti-corrosion coating with zinc powder, aluminum powder, chromic acid and deionized water as its main components. Its advantages are as follows: 1. Superior corrosion resistance: The Dacromet film layer is only 4-8μm thick, but its rust prevention effect is 7-10 times greater than that of traditional electrogalvanizing, hot-dip galvanizing, or paint coating methods. Standard parts and pipe fittings treated with the Dacromet process have not shown any red rust after a salt spray test of more than 1200 hours.

[0046] 2. High heat resistance: Dacromet is resistant to high temperature corrosion and its heat resistance temperature can reach over 300°C. However, the traditional galvanizing process will peel off and become scrapped when the temperature reaches 100°C.

[0047] 3. No hydrogen embrittlement: Dacromet's processing technology determines that Dacromet has no hydrogen embrittlement phenomenon, so Dacromet is very suitable for coating of stress-bearing parts.

[0048] 4. Good bonding and recoating performance: Dacromet coating has good bonding with the metal substrate and strong adhesion with other additional coatings. The treated parts are easy to spray and color, and its bonding with organic coatings even exceeds that of phosphate film.

[0049] In addition, the transition layer 12 can also be obtained by surface treatment such as silane treatment, ceramic treatment, and sandblasting to improve the surface's corrosion resistance and adhesion.

[0050] Among them, silane treatment is an environmentally friendly metal surface treatment technology with organic silane as the main raw material. It improves the adhesion and anti-corrosion performance of the coating by forming a covalent bond film layer. It has the advantages of no heavy metal pollution, low energy consumption and simple process.

[0051] It should be noted that a molybdenum disulfide coating 13 is coated on the surface of the inner cavity 11 of the cylinder body 10. The molybdenum disulfide coating 13 has a good self-lubricating effect, which can effectively reduce the scratches on the piston or the middle cylinder caused by the failure of the oil film, and further avoid the scratches on the piston or the middle cylinder; and a transition layer 12 is coated between the molybdenum disulfide coating 13 and the surface of the inner cavity 11. While preventing corrosion, it effectively improves the adhesion strength of the molybdenum disulfide coating 13, avoids the molybdenum disulfide coating 13 from falling off, and further reduces the chance of scratches on the piston or the middle cylinder.

[0052] Based on the same inventive concept, an embodiment of the present invention provides a hydraulic breaker hammer, including the above-mentioned anti-strain breaker hammer cylinder assembly.

[0053] The beneficial effect of the hydraulic breaker provided by the present invention is as follows: compared with the prior art, the hydraulic breaker provided by the present invention breaks the traditional high-precision cylindricity thinking in order to avoid damage to the piston caused by lateral offset force, and is provided with a cylinder body 10 or piston with a taper. According to the deflection shape of the piston, the inner wall of the middle diameter section 111 of the middle cylinder or the side wall of the middle section 21 of the piston is processed into a conical surface, and the inner wall of the small diameter section 112 of the middle cylinder or the side wall of the lower section 22 of the piston is processed into a conical surface. In this way, after the piston is offset, the previous point contact is changed to line contact, which effectively reduces the local contact pressure, effectively reduces the probability of oil film damage, and thereby effectively reduces the occurrence of strain.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A strain-proof breaker hammer cylinder assembly, characterized in that: include: The cylinder body has an inner cavity, the inner cavity is divided into a middle diameter section of the middle cylinder and a small diameter section of the middle cylinder, the diameter of the middle diameter section of the middle cylinder is larger than the diameter of the small diameter section of the middle cylinder, and the small diameter section of the middle cylinder is arranged at the lower side of the middle diameter section of the middle cylinder; A piston is slidably disposed in the inner cavity, the piston being divided into a middle piston section and a lower piston section, the diameter of the middle piston section being larger than the diameter of the lower piston section, the middle piston section being in sliding engagement with the middle diameter section of the middle cylinder, and the lower piston section being in sliding engagement with the small diameter section of the middle cylinder; Among them, the inner wall of the middle diameter section of the middle cylinder or the side wall of the middle section of the piston is a conical surface, and the inner wall of the small diameter section of the middle cylinder or the side wall of the lower section of the piston is a conical surface. After the piston is deflected by radial force, the side wall of the middle section of the piston forms a line contact with the inner wall of the middle diameter section of the middle cylinder, and the side wall of the lower section of the piston forms a line contact with the inner wall of the small diameter section of the middle cylinder.

2. The anti-strain breaker hammer cylinder assembly according to claim 1, characterized in that: The inner walls of the middle diameter section of the middle cylinder and the small diameter section of the middle cylinder are conical surfaces, and the diameter of the middle diameter section of the middle cylinder gradually decreases from top to bottom, and the diameter of the small diameter section of the middle cylinder gradually increases from top to bottom; the side wall of the piston is a cylindrical surface; after the piston is deflected by radial force, the side wall of the middle section of the piston forms a line contact with the inner wall of the middle diameter section of the middle cylinder, and the side wall of the lower section of the piston forms a line contact with the inner wall of the small diameter section of the middle cylinder.

3. The anti-strain breaker hammer cylinder assembly according to claim 1, characterized in that: The inner walls of the middle diameter section of the middle cylinder and the small diameter section of the middle cylinder are cylindrical surfaces, and the side walls of the middle section of the piston and the lower section of the piston are conical surfaces, and the diameter of the middle section of the piston gradually increases from top to bottom, and the diameter of the lower section of the piston gradually decreases from top to bottom; after the piston is deflected by radial force, the side wall of the middle section of the piston forms a line contact with the inner wall of the middle diameter section of the middle cylinder, and the side wall of the lower section of the piston forms a line contact with the inner wall of the small diameter section of the middle cylinder.

4. The anti-strain breaker hammer cylinder assembly according to claim 1, characterized in that: The inner wall of the middle diameter section of the middle cylinder is a cylindrical surface, the inner wall of the small diameter section of the middle cylinder is a conical surface, and the diameter of the small diameter section of the middle cylinder gradually increases from top to bottom; the middle section of the piston has a conical side wall surface, the side wall of the lower section of the piston is a cylindrical surface, and the diameter of the middle section of the piston gradually increases from top to bottom; after the piston is deflected by radial force, the side wall of the middle section of the piston forms a line contact with the inner wall of the middle diameter section of the middle cylinder, and the side wall of the lower section of the piston forms a line contact with the inner wall of the small diameter section of the middle cylinder.

5. The anti-strain breaker hammer cylinder assembly according to any one of claims 1 to 4, characterized in that: The gap between the cylinder and the piston is 0.06-0.15 mm.

6. The anti-strain breaker hammer cylinder assembly according to claim 5, characterized in that: The sum of the tapers of the middle diameter section of the middle cylinder and the middle section of the piston is 0.000036-0.000056, and the sum of the tapers of the small diameter section of the middle cylinder and the lower section of the piston is 0.0001-0.00015.

7. The anti-strain breaker hammer cylinder assembly according to claim 1, characterized in that: It also includes a molybdenum disulfide coating, which is coated on the inner wall of the inner cavity and has a thickness of 0.005-0.01 mm.

8. The anti-strain breaker hammer cylinder assembly according to claim 7, characterized in that: It also includes a transition layer, which is coated between the inner wall of the inner cavity and the molybdenum disulfide coating and has a thickness of 0.005-0.01 mm.

9. A hydraulic breaker, characterized in that: It comprises the anti-strain breaker hammer cylinder assembly according to any one of claims 1-8.

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