Dustproof structure of hydraulic cylinder and hydraulic cylinder
By using metal outer and inner bushings in the hydraulic cylinder, combined with air passages to maintain high air pressure inside the cavity, the dustproof problem of rubber dust covers under high temperature and negative pressure environments is solved, achieving protection and sealing effects for the piston rod.
Patent Information
- Application Number
- CN202520060921.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-10
- Publication Date
- 2025-12-09
- Estimated Expiration
- 2035-01-10
AI Technical Summary
Existing retractable dust covers made of rubber are unable to withstand high temperature and negative pressure environments, resulting in scratches on the surface of the hydraulic cylinder piston rod and affecting the sealing effect.
The outer and inner bushings are made of metal instead of rubber dust covers. Compressed gas is supplied through the air duct to maintain the air pressure inside the cavity higher than that of the external environment, preventing dust from entering and providing a cooling effect in high-temperature environments.
It achieves effective dust prevention in high temperature and negative pressure environments, avoiding scratches on the piston rod surface and damage to the sealing effect, and is suitable for extreme working conditions.
Smart Images
Figure CN223648203U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the technical field of general fluid working systems, specifically relating to straight cylinder type hydraulic cylinders, and more particularly to a dustproof structure for a hydraulic cylinder and a hydraulic cylinder. Background Technology
[0002] Hydraulic cylinders, as hydraulic actuators, are widely used in various industries. In some industries, customers have increasingly stringent requirements for hydraulic cylinders, among which the protection of the piston rod is a common issue. Under normal circumstances, during the reciprocating operation of a hydraulic cylinder, the external environment in which the cylinder operates may contain a large amount of impurities and dust, causing a large number of particles to adhere to the piston rod. During the reciprocating motion of the piston rod, some of these foreign objects will get stuck between the seal ring and the piston rod. Over time, these foreign objects will scratch the surface of the piston rod and may even affect the sealing effect.
[0003] In related technologies, retractable dust covers are generally made of rubber. The two ends of the dust cover are fixed to the piston rod end and the cylinder body end respectively by clamps, so that the dust cover can extend or retract along with the piston rod during the reciprocating motion of the hydraulic cylinder.
[0004] However, the commonly used rubber dust covers can only withstand temperatures up to about 400℃ and are difficult to withstand negative pressure.
[0005] Therefore, how to solve the technical problem that retractable dust covers made of rubber are unable to withstand high-temperature and / or negative pressure environments is a problem that urgently needs to be solved by those skilled in the art.
[0006] It should be noted that the information disclosed in this background section is only for understanding the background technology of the present application concept, and therefore, the above description is not considered to constitute prior art information. Utility Model Content
[0007] This disclosure provides at least one dustproof structure for a hydraulic cylinder and a hydraulic cylinder.
[0008] In a first aspect, embodiments of this disclosure provide a hydraulic cylinder, comprising: a cylinder body with a guide sleeve disposed at one end opening; an inner bushing fitted onto the guide sleeve; an end cap connected to the cylinder body to press the inner bushing tightly onto the guide sleeve; and a piston rod passing through the guide sleeve, wherein an outer bushing is fitted onto the piston rod, the outer bushing reciprocating with the piston rod and slidingly engaging with the inner bushing; wherein both the inner bushing and the outer bushing are made of metal.
[0009] In one optional embodiment, the hydraulic cylinder further includes: an air passage; a cavity is formed between the guide sleeve, inner bushing, outer bushing, and piston rod; one end of the air passage communicates with the cavity, and the other end extends to the surface of the hydraulic cylinder; the cavity is adapted to receive compressed gas through the air passage so that the internal air pressure of the cavity is greater than the external ambient air pressure.
[0010] In one alternative embodiment, the air passage is formed on the guide sleeve; one end of the air passage extends to the outer end face of the guide sleeve; the other end of the air passage extends to the side wall of the guide sleeve and protrudes from the surface of the cylinder.
[0011] In one alternative embodiment, the outer bushing is threadedly connected to the piston rod; the compressed gas in the cavity is discharged through the gap at the threaded connection between the outer bushing and the piston rod.
[0012] In one optional embodiment, an annular boss is provided in the middle of the outer wall of the guide sleeve; the guide sleeve abuts against the opening of the cylinder body through the annular boss; wherein, one side of the annular boss is located inside the cylinder body, and the inner liner is fitted on the other side.
[0013] In one optional embodiment, one end of the inner liner abuts against the annular boss and has an outwardly flanged edge; the end cap is connected to the cylinder body, and the inner liner is pressed against the annular boss by pressing the flanged edge.
[0014] In one optional embodiment, a groove is formed on the side wall of the inner liner; a sealing ring is provided in the groove.
[0015] In one alternative embodiment, a retaining ring is fitted on the side wall of the piston rod to prevent the outer bushing from retracting.
[0016] Secondly, embodiments of this disclosure also provide a dustproof structure for a hydraulic cylinder, comprising: an inner bushing for being disposed on a cylinder body; and an outer bushing for being disposed on a piston rod; wherein the outer bushing is adapted to slide relative to the inner bushing by reciprocating along with the piston rod.
[0017] In one alternative embodiment, one end of the inner bushing is provided with a flange, and the inner bushing is pressed onto the cylinder body by the flange; the outer bushing is threadedly connected to the piston rod to follow the reciprocating movement of the piston rod.
[0018] The beneficial effects of this utility model are that the dustproof structure of this hydraulic cylinder and the use of metal outer and inner bushings to replace the existing retractable dust cover made of rubber enable the outer and inner bushings to be used in high temperature and / or negative pressure environments.
[0019] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objectives and other advantages of this invention are realized and obtained through the structures particularly pointed out in the description and the accompanying drawings.
[0020] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings. Attached Figure Description
[0021] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0022] Figure 1 This is a cross-sectional structural schematic diagram of a hydraulic cylinder provided in an embodiment of the present disclosure;
[0023] Figure 2 This is a schematic diagram of the structure of an outer bushing provided in an embodiment of the present disclosure;
[0024] Figure 3 A schematic diagram of the mating structure of a guide sleeve provided in an embodiment of this disclosure;
[0025] Figure 4 This is a schematic diagram of the structure of an inner liner provided in an embodiment of the present disclosure.
[0026] In the picture:
[0027] Cylinder 1, Opening 11
[0028] Guide sleeve 2, annular boss 21
[0029] Inner liner 3, flange 31, sealing ring 32, groove 33;
[0030] End cap 4;
[0031] Piston rod 5;
[0032] Outer bushing 6, through hole 61;
[0033] Airway 7;
[0034] Cavity 8. Detailed Implementation
[0035] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0036] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the figures, the thickness of parts may be exaggerated or reduced for the purpose of effectively depicting the technical content.
[0037] The following detailed description, with reference to the accompanying drawings, describes some embodiments of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0038] like Figure 1 As shown, at least one embodiment provides a hydraulic cylinder, including: cylinder body 1, guide sleeve 2, inner bushing 3, end cap 4, piston rod 5, and outer bushing 6.
[0039] like Figure 1 As shown, in some embodiments, the cylinder 1 is used to insert a piston rod 5, and the reciprocating movement of the piston rod 5 realizes the flow of liquid.
[0040] like Figure 1 As shown, in some embodiments, the guide sleeve 2 is disposed at the opening 11 of the cylinder body 1, and is used to insert the piston rod 5, thereby guiding the movement direction of the piston rod 5.
[0041] like Figure 1 As shown, in some embodiments, the inner liner 3 is connected to the cylinder body 1 via the end cap 4 and is pressed against the guide sleeve 2 by the end cap 4.
[0042] like Figure 1 As shown, in some embodiments, the outer bushing 6 is fitted onto the piston rod 5 and moves back and forth with the piston rod 5. During the movement, the outer bushing 6 achieves dust protection for the piston rod 5 by slidingly engaging with the inner bushing 3.
[0043] In this embodiment, the outer bushing 6 moves back and forth with the piston rod 5, so that the piston rod 5 is always blocked. Dust will only adhere between the inner bushing 3 and the outer bushing 6, and will not adhere to the piston rod 5. At the same time, both the outer bushing 6 and the inner bushing 3 can be made of metal materials with high hardness and high temperature resistance, so that they can be used in extreme working conditions, such as high temperature environment, corrosion ring and negative pressure environment.
[0044] In this embodiment, in hydraulic cylinders with different strokes, it is only necessary to adjust the lengths of the inner bushing 3 and the outer bushing 6 so that the relative sliding surfaces of the inner bushing 3 and the outer bushing 6 do not completely separate throughout the entire stroke of the hydraulic cylinder.
[0045] like Figure 1 As shown, in some embodiments, a cavity 8 is formed between the guide sleeve 2, inner bushing 3, outer bushing 6, and piston rod 5. During the reciprocating movement of the outer bushing 6 following the piston rod 5, the volume of the cavity 8 may expand or contract. During the expansion of the cavity 8, a negative pressure is generated inside the cavity 8, which can easily cause dust to be drawn into the cavity 8, thereby damaging the piston rod 5. Therefore, in this embodiment, the hydraulic cylinder is also provided with an air passage 7, one end of which is connected to the cavity 8, and the other end extends to the surface of the hydraulic cylinder.
[0046] In this embodiment, the cavity 8 receives compressed gas through the air passage 7, so that when the volume of the cavity 8 expands or contracts, the air pressure inside the cavity 8 is always greater than the air pressure of the external environment, thereby preventing the cavity 8 from sucking in dust due to negative pressure during the expansion process.
[0047] In this embodiment, compressed air can be introduced into the cavity 8 to cool it in a high-temperature environment.
[0048] like Figure 1 As shown, in some embodiments, optionally, the air passage 7 is formed on the guide sleeve 2; one end of the air passage 7 extends to the outer end face of the guide sleeve 2; the other end of the air passage 7 extends to the side wall of the guide sleeve 2 and passes through the surface of the cylinder body 1.
[0049] In this embodiment, the connection port between the air passage 7 and the air source can be located at any part of the cylinder body 1, as long as the requirements are met.
[0050] like Figure 1 As shown, in some embodiments, the outer bushing 6 is threadedly connected to the piston rod 5; the compressed gas in the cavity 8 is discharged through the gap at the threaded connection between the outer bushing 6 and the piston rod 5.
[0051] like Figure 2 As shown, in some embodiments, the outer bushing 6 has a through hole 61, and the inner wall of the through hole 61 is provided with an internal thread. The connection between the outer bushing 6 and the piston rod 5 is realized by the internal thread engaging with the external thread on the side wall of the piston rod 5.
[0052] like Figure 3 As shown, in some embodiments, an annular boss 21 is provided in the middle of the outer wall of the guide sleeve 2; the guide sleeve 2 abuts against the opening 11 of the cylinder body 1 through the annular boss 21; wherein, one side of the annular boss 21 is located inside the cylinder body 1, and the other side is fitted with an inner liner 3.
[0053] like Figure 3 , Figure 4 As shown, in some embodiments, one end of the inner bushing 3 abuts against the annular boss 21 and is provided with a flange 31 extending outward; the end cap 4 is connected to the cylinder body 1, and the inner bushing 3 is pressed against the annular boss 21 by pressing the flange 31.
[0054] like Figure 3 As shown, in some embodiments, a sealing ring 32 is fitted on the side wall of the inner liner 3 to prevent dust from entering the cavity 8 through the gap between the inner liner 3 and the outer liner 6.
[0055] like Figure 4 As shown, in some embodiments, grooves 33 are provided on the side wall of the inner liner 3 for installing the sealing ring 32 and preventing the sealing ring 32 from shifting.
[0056] like Figure 3 As shown, in some embodiments, a retaining ring 51 for blocking the outer bushing 6 from retracting is fitted on the side wall of the piston rod 5.
[0057] like Figure 3 As shown, in some embodiments, when the piston rod 5 retracts to its maximum stroke, the inner bushing 3 and the outer bushing 6 partially overlap, thereby preventing the inner bushing 3 from separating from the outer bushing 6.
[0058] like Figure 3 As shown, at least one embodiment also provides a dustproof structure for a hydraulic cylinder, comprising: an inner bushing 3 for mounting on a cylinder body 1; and an outer bushing 6 for mounting on a piston rod 5; wherein the outer bushing 6 is adapted to slide relative to the inner bushing 3 by reciprocating along with the piston rod 5.
[0059] In some embodiments, one end of the inner bushing 3 is provided with a flange 31, and the inner bushing 3 is pressed onto the cylinder body 1 by the flange 31; the outer bushing 6 is threadedly connected to the piston rod 5 to follow the reciprocating movement of the piston rod 5.
[0060] In summary, the dustproof structure of this hydraulic cylinder, and the replacement of the existing retractable dust cover made of rubber with a metal outer bushing 6 and an inner bushing 3, enable the outer bushing 6 and the inner bushing 3 to be used in high-temperature and / or negative pressure environments.
[0061] In this document, when it is said that the first component is located on the second component, this can mean that the first component can be directly formed on the second component, or that the third component can be inserted between the first component and the second component.
[0062] In this document, when an element or layer is referred to as “located,” “joined to,” “connected to,” “attached to,” or “coupled to” another element or layer, it may be directly located, joined, connected, attached to, or coupled to the other element or layer, or there may be intermediate elements or layers present. Conversely, when an element is referred to as “directly on another element or layer,” “directly joined to,” “directly connected to,” “directly attached to,” or “directly coupled to” another element or layer, there may be no intermediate elements or layers present. Other terms used to describe relationships between elements should be interpreted in a similar manner (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and / or” includes any and all combinations of one or more of the related listed items.
[0063] In this document, exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. As used herein, expressions such as “at least one of…” modify the entire list of elements when following a list of elements, rather than individual elements in the list. For example, the expression “at least one of a, b, and c” should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, or all of a, b, and c.
[0064] The terminology used herein is for the purpose of describing specific exemplary configurations only and is not intended to be limiting. As used herein, the singular articles “a,” “an,” and “the” may also be intended to include plural forms unless otherwise clearly stated herein. The terms “comprising,” “including,” and “having” are inclusive and thus specify the presence of features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein should not be construed as requiring them to be performed in the specific order discussed or shown, unless specifically identified as such. Additional or alternative steps may be employed.
[0065] As used herein, the phrases “in one embodiment,” “according to one embodiment,” “in some embodiments,” etc., generally refer to the fact that a particular feature, structure, or characteristic following the phrase can be included in at least one embodiment of this disclosure. Therefore, a particular feature, structure, or characteristic can be included in more than one embodiment of this disclosure, such that these phrases do not necessarily refer to the same embodiment. As used herein, the terms “example,” “exemplary,” etc., are used to “serve as an example, instance, or illustration.” Any implementation, aspect, or design described herein as “example” or “exemplary” is not necessarily to be construed as preferred or superior to other implementations, aspects, or designs. Rather, the use of the terms “example,” “exemplary,” etc., is intended to present concepts in a specific manner.
[0066] In the description of the embodiments of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0067] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence unless expressly indicated herein. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer, or segment discussed above may be referred to as the second element, component, region, layer, or segment.
[0068] Spatially relative terms, such as “inside,” “outside,” “below,” “below,” “down,” “above,” “up,” etc., may be used herein to describe the relationship between one element or feature illustrated in the figures and another element or feature. In addition to the orientations depicted in the figures, spatially relative terms may be intended to cover different orientations of the device in use or operation. For example, if the device in the figure is flipped, an element described as “below” or “below” other elements or features would be oriented as “above” other elements or features. Thus, the example term “below” can cover both above and below orientations. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein are interpreted accordingly.
[0069] In the above discussion, unless otherwise stated, when used to describe numerical values, the terms “about,” “approximately,” “basically,” etc., indicate a change of + / - 10% in that value.
[0070] Based on the above-described preferred embodiments of this utility model, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this utility model. The technical scope of this utility model is not limited to the contents of the specification, but must be determined according to the scope of the claims.
Claims
1. A hydraulic cylinder, characterized in that, include: The cylinder body (1) has a guide sleeve (2) at one end of its opening (11); The inner liner (3) is fitted onto the guide sleeve (2); End cap (4) is connected to cylinder body (1) to press inner bushing (3) onto guide sleeve (2); The piston rod (5) is inserted in the guide sleeve (2), and an outer bushing (6) is fitted on the piston rod (5). The outer bushing (6) moves back and forth with the piston rod (5) and slides in cooperation with the inner bushing (3). The inner bushing (3) and the outer bushing (6) are both made of metal.
2. The hydraulic cylinder as described in claim 1, characterized in that, Also includes: Airway (7); A cavity (8) is formed between the guide sleeve (2), the inner liner (3), the outer liner (6), and the piston rod (5); One end of the air passage (7) is connected to the cavity (8), and the other end extends to the surface of the hydraulic cylinder; The cavity (8) is adapted to receive compressed gas through the air passage (7) so that the air pressure inside the cavity (8) is greater than the air pressure of the external environment.
3. The hydraulic cylinder as described in claim 2, characterized in that, The air passage (7) is opened on the guide sleeve (2); One end of the airway (7) extends to the outer end face of the guide sleeve (2); The other end of the air passage (7) extends to the side wall of the guide sleeve (2) and protrudes from the surface of the cylinder (1).
4. The hydraulic cylinder as described in claim 2, characterized in that, The outer bushing (6) is threadedly connected to the piston rod (5); The compressed gas in the cavity (8) is discharged through the gap at the threaded connection between the outer bushing (6) and the piston rod (5).
5. The hydraulic cylinder as described in claim 1, characterized in that, The guide sleeve (2) has an annular boss (21) in the middle of its outer wall. The guide sleeve (2) abuts against the opening (11) of the cylinder body (1) via the annular boss (21). One side of the annular boss (21) is located inside the cylinder body (1), and the other side is fitted with the inner liner (3).
6. The hydraulic cylinder as described in claim 5, characterized in that, One end of the inner liner (3) abuts against the annular boss (21) and is provided with a flange (31) facing outward. The end cap (4) is connected to the cylinder body (1), and the inner bushing (3) is pressed onto the annular boss (21) by pressing the flange (31).
7. The hydraulic cylinder as described in claim 1, characterized in that, The inner liner (3) has grooves (33) on its side wall; A sealing ring (32) is provided in the groove (33).
8. The hydraulic cylinder as described in claim 4, characterized in that, The piston rod (5) is fitted with a retaining ring (51) on its side wall to prevent the outer bushing (6) from retracting.
9. A dustproof structure for a hydraulic cylinder, characterized in that, include: Inner bushing (3), used to be installed on cylinder body (1); Outer bushing (6) is used to be mounted on piston rod (5); The outer bushing (6) is adapted to slide relative to the inner bushing (3) by reciprocating along with the piston rod (5).
10. The dustproof structure of the hydraulic cylinder as described in claim 9, characterized in that, One end of the inner liner (3) is provided with a flange (31), and the inner liner (3) is pressed onto the cylinder body (1) by the flange (31); The outer bushing (6) is threadedly connected to the piston rod (5) to follow the reciprocating movement of the piston rod (5).