Swing hydraulic cylinder

Abstract

The present invention discloses a swing hydraulic cylinder, comprising: a cylinder body, a channel extending along its axial direction is defined in the cylinder body; an output shaft, at least a part of the output shaft is arranged in the channel and extends along the axial direction of the channel, at least a part of the outer wall surface of the output shaft is spaced apart from the inner wall surface of the channel; an end cover, the end cover is arranged at one end of the channel and connected to the output shaft; a piston; a fixing member; a first stopper, the first stopper is arranged in the channel and is located between one end of the output shaft and a first oil delivery hole; a first plane thrust needle roller bearing, the first plane thrust needle roller bearing is arranged between the first stopper and one end of the output shaft; a first wear-resistant ring, the first wear-resistant ring is arranged on the outer periphery of the first thrust needle roller bearing and is located between the first thrust needle roller bearing and the cylinder body. The problem of wear of the first plane thrust needle roller bearing on the inner hole of the cylinder body is solved, and the first wear-resistant ring has the advantages of low cost and easy replacement, which prolongs the service life of the swing hydraulic cylinder and reduces the cost.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic cylinders, and in particular relates to a swing hydraulic cylinder. Background Art

[0002] At present, thrust needle roller bearings and thrust washers are widely used in swing hydraulic cylinders to reduce the friction of the output screw during rotation. During the use of the swing hydraulic cylinder, the thrust needle roller bearings and thrust washers in the swing hydraulic cylinder will be worn at the contact points with the inner hole of the cylinder. The greater the eccentric load, the greater the wear, and the cylinder will soon fail.

[0003] However, in actual use, the swing hydraulic cylinder has many eccentric load conditions, so the longer the support length, the better. Guide rings are widely used as conventional supports in swing hydraulic cylinders, but the swing hydraulic cylinder has a compact structure. When using conventional guide rings as supports, grooves need to be designed for installation, which limits the lengthening of the guide rings.

[0004] How to prevent the thrust needle roller bearing and thrust gasket from wearing against the inner hole of the cylinder during movement and reduce the eccentric load of the swing hydraulic cylinder is the current research and development focus. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0006] To this end, the present invention provides a swing hydraulic cylinder, which has the advantages of long service life and the like.

[0007] The swing hydraulic cylinder according to the embodiment of the present invention comprises: a cylinder body, a channel extending along the axial direction of the cylinder body is defined; an output shaft, at least a part of the output shaft is arranged in the channel and extends along the axial direction of the channel, at least a part of the outer wall surface of the output shaft is spaced apart and distributed from the inner wall surface of the channel; an end cover, the end cover is arranged at one end of the channel and connected to the output shaft; a piston, the piston is located in the channel and divides the channel into a first chamber and a second chamber spaced apart from each other, the cylinder body is provided with a first oil delivery hole connected to the first chamber and a second oil delivery hole connected to the second chamber, the piston is sleeved on the outer periphery of the output shaft and can reciprocate along the axial direction of the channel under the action of the pressure oil in the first chamber and the second chamber, and the inner wall of the piston At least a portion of the surface forms a first spiral pair with the outer wall surface of the output shaft, and at least a portion of the outer wall surface of the piston is spaced apart from the inner wall surface of the channel; a fixing member, the fixing member is arranged in the channel and is located between the outer wall surface of the piston and the inner wall surface of the channel in the radial direction of the channel and forms a second spiral pair with the outer wall surface of the piston in the opposite rotation direction to the first spiral pair; a first limiting member, the first limiting member is arranged in the channel and is located between one end of the output shaft and the first oil delivery hole; a first planar thrust needle roller bearing, the first planar thrust needle roller bearing is arranged between the first limiting member and one end of the output shaft; a first wear-resistant ring, the first wear-resistant ring is arranged on the outer periphery of the first thrust needle roller bearing and is located between the first thrust needle roller bearing and the cylinder body.

[0008] According to the swing hydraulic cylinder of the embodiment of the present invention, by adopting a cylinder body, an output shaft, an end cover, a piston, a fixing piece, a first limit piece, a first planar thrust needle roller bearing and a first wear-resistant ring, not only can the linear motion of the piston be converted into the rotational motion of the output shaft by utilizing a large helix angle, but also the first planar thrust needle roller bearing can be prevented from directly contacting the cylinder body, thereby solving the problem of wear on the inner hole of the cylinder body. In addition, the first wear-resistant ring has the advantages of low cost and easy replacement, thereby extending the service life of the swing hydraulic cylinder and reducing production costs.

[0009] According to one embodiment of the present invention, the inner wall surface of the first thrust needle roller bearing abuts against the outer wall surface of the output shaft, and the outer wall surface of the first thrust needle roller bearing abuts against the wear-resistant ring.

[0010] According to an embodiment of the present invention, the swing hydraulic cylinder further includes: a first sleeve, which is sleeved on the outer circumference of the output shaft and located between one end of the output shaft and the first wear-resistant ring.

[0011] According to one embodiment of the present invention, the inner diameter of the first wear-resistant ring is the same as the inner diameter of the first sleeve.

[0012] According to one embodiment of the present invention, the swing hydraulic cylinder also includes: a second limit member, which is arranged in the channel and located between the fixing member and the end cover, and the second limit member cooperates with the first limit member to limit the displacement of the output shaft along its axial direction; a second planar thrust needle roller bearing, which is arranged between the second planar thrust needle roller bearing and the end cover; and a second wear-resistant ring, which is arranged on the outer periphery of the second thrust needle roller bearing and located between the second planar thrust needle roller bearing and the cylinder body.

[0013] According to one embodiment of the present invention, the swing hydraulic cylinder further includes: a second sleeve, which is sleeved on the outer circumference of the output shaft and located between the end cover and the second wear-resistant ring.

[0014] According to one embodiment of the present invention, the inner diameters of the second wear-resistant ring and the second sleeve are the same.

[0015] According to an embodiment of the present invention, the swing hydraulic cylinder further comprises: two washers, which are respectively arranged on both sides of the first planar thrust needle roller bearing along the axial direction of the channel.

[0016] According to one embodiment of the present invention, the first wear-resistant ring is located on the outer periphery of the gasket.

[0017] According to an embodiment of the present invention, an outer wall surface of the output shaft is provided with an annular step portion, and the first planar thrust needle roller bearing is provided on the annular step portion.

[0018] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0020] Figure 1 is a schematic structural diagram of a swing hydraulic cylinder according to an embodiment of the present invention;

[0021] Figure 2 yes Figure 1 Magnified view of area A.

[0022] Reference numerals:

[0023] Swing hydraulic cylinder 100;

[0024] Cylinder body 10; channel 11; first chamber 12; second chamber 13;

[0025] Output shaft 20; step portion 23; first sleeve 25; second sleeve 26;

[0026] End cap 30;

[0027] Piston 40; first spiral pair 41;

[0028] Fixing member 50; second screw pair 51;

[0029] A first stopper 60;

[0030] A second limiting member 70;

[0031] A first plane thrust needle roller bearing 80; a first wear-resistant ring 81;

[0032] Second planar thrust needle roller bearing 90; second wear-resistant ring 91. DETAILED DESCRIPTION

[0033] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0034] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] The swing hydraulic cylinder 100 according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

[0037] like Figure 1 and Figure 2 As shown, the swing hydraulic cylinder 100 according to the embodiment of the present invention includes: a cylinder body 10, an output shaft 20, an end cover 30, a piston 40, a fixing member 50, a first limit member 60, a first planar thrust needle roller bearing 80 and a first wear-resistant ring 81.

[0038] Specifically, according to the swing hydraulic cylinder 100 of the embodiment of the present invention, a channel 11 extending along the axial direction thereof is defined in the cylinder body 10; at least a portion of the output shaft 20 is arranged in the channel 11 and extends along the axial direction of the channel 11, and at least a portion of the outer wall surface of the output shaft 20 is spaced apart and distributed from the inner wall surface of the channel 11; the end cover 30 is arranged at one end of the channel 11 and connected to the output shaft 20; the piston 40 is located in the channel 11 and divides the channel 11 into a first chamber 12 and a second chamber 13 spaced apart from each other, the cylinder body 10 is provided with a first oil delivery hole communicating with the first chamber 12 and a second oil delivery hole communicating with the second chamber 13, the piston 40 is sleeved on the outer periphery of the output shaft 20 and can move along the axial direction of the channel 11 under the action of the pressure oil in the first chamber 12 and the second chamber 13 The piston 40 performs reciprocating motion, at least a portion of the inner wall surface of the piston 40 and the outer wall surface of the output shaft 20 form a first spiral pair 41, and at least a portion of the outer wall surface of the piston 40 is spaced apart from the inner wall surface of the channel 11; the fixing member 50 is arranged in the channel 11 and is located between the outer wall surface of the piston 40 and the inner wall surface of the channel 11 in the radial direction of the channel 11, and forms a second spiral pair 51 with a rotation direction opposite to the first spiral pair 41 between the outer wall surface of the piston 40 and the outer wall surface of the piston 40; the first limit member 60 is arranged in the channel 11 and is located between one end of the output shaft 20 and the first oil delivery hole; the first planar thrust needle roller bearing 80 is arranged between the first limit member 60 and one end of the output shaft 20; the first wear-resistant ring 81 is arranged on the outer periphery of the first thrust needle roller bearing and is located between the first thrust needle roller bearing and the cylinder body 10.

[0039] In other words, the swing hydraulic cylinder 100 according to the embodiment of the present invention is mainly composed of a cylinder body 10, an output shaft 20, an end cover 30, a piston 40, a fixing member 50, a first stopper 60, a first plane thrust needle roller bearing 80 and a first wear-resistant ring 81. A channel 11 extending along the axial direction is defined in the cylinder body 10, a piston 40 and a fixing member 50 are installed in the channel 11, the piston 40 is provided with a mounting hole extending along the axial direction, a part of the output shaft 20 extends into the channel 11 and passes through the mounting hole of the piston 40, and at least a part of the outer wall surface of the output shaft 20 and at least a part of the inner wall surface of the piston 40 cooperate to form a first spiral pair 41. Specifically, the inner spiral spline on the piston 40 and the outer spiral spline on the output shaft 20 can be meshed with each other to form the first spiral pair 41. The fixing member 50 is connected to the cylinder body 10, and the fixing member 50 and the piston 40 cooperate to form a second spiral pair 51. Specifically, the outer helical spline on the piston 40 and the inner helical spline on the fixing member 50 may be meshed with each other to form a second helical pair 51 .

[0040] The second helical pair 51 cooperates with the first helical pair 41 to convert the axial movement of the piston 40 into the circumferential rotation of the output shaft 20. Specifically, the pressure oil is delivered to the first chamber 12 through the first oil delivery hole, and the piston 40 moves axially to the right under the pressure in the first chamber 12. The outer wall of the piston 40 and the inner wall of the fixing member 50 are spirally driven, and the piston 40 can rotate circumferentially while moving axially. Since the second helical pair 51 rotates in the opposite direction to the first helical pair 41, the output angle can make the two-stage helical pair angle vectors superimposed. The inner wall of the piston 40 and the outer wall of the output shaft 20 are spirally driven, and the output shaft 20 can rotate circumferentially, thereby converting the axial movement of the piston 40 into the axial rotation of the output shaft 20. At least a portion of the first spiral pair 41 is staggered with the second spiral pair 51 along the axial direction of the channel 11. By adopting a staggered structure, not only can the two-stage spiral pairs be more stable during the mutual meshing process, but also the coaxiality of the fixing member 50, the piston 40 and the output shaft 20 can be higher.

[0041] The first stopper 60 is arranged in the passage 11 and between one end of the output shaft 20 and the first oil delivery hole. The first plane thrust needle roller bearing 80 is arranged between the first stopper 60 and one end of the output shaft 20, so as to facilitate the circumferential rotation of the output shaft 20. The first wear-resistant ring 81 is arranged on the outer periphery of the first thrust needle roller bearing. In other words, the first thrust needle roller bearing is located between the first wear-resistant ring 81 and the output shaft 20, and the first wear-resistant ring 81 is located between the first thrust needle roller bearing and the cylinder body 10, so as to separate the first thrust needle roller bearing from the cylinder body 10. The first wear-resistant ring 81 is made of wear-resistant material and has high hardness, so as to effectively prevent the first thrust needle roller bearing from wearing the inner hole of the cylinder body 10 when the first thrust needle roller bearing moves.

[0042] Therefore, according to the swing hydraulic cylinder 100 of the embodiment of the present invention, by adopting the cylinder body 10, the output shaft 20, the end cover 30, the piston 40, the fixing member 50, the first limit member 60, the first planar thrust needle roller bearing 80 and the first wear-resistant ring 81, not only can the linear motion of the piston 40 be converted into the rotational motion of the output shaft 20 by utilizing the large helix angle, but also the first planar thrust needle roller bearing 80 can be prevented from directly contacting the cylinder body 10, thereby solving the problem of wear on the inner hole of the cylinder body 10. In addition, the first wear-resistant ring 81 has the advantages of low cost and easy replacement, thereby extending the service life of the swing hydraulic cylinder 100 and reducing the production cost.

[0043] Furthermore, the inner wall surface of the first thrust needle roller bearing abuts against the outer wall surface of the output shaft 20, and the outer wall surface of the first thrust needle roller bearing abuts against the wear-resistant ring. The outer wall surface of the first thrust needle roller bearing is adjacent to the inner wall surface of the first wear-resistant ring 81, thereby preventing the first thrust needle roller bearing from generating friction with the cylinder body 10 when moving.

[0044] Optionally, the swing hydraulic cylinder 100 further includes: a first sleeve 25, which is sleeved on the outer periphery of the output shaft 20 and is located between one end of the output shaft 20 and the first wear-resistant ring 81. The first sleeve 25 replaces the traditional guide ring with a sleeve to avoid setting a guide ring groove at the output screw, that is, the first sleeve 25 is located between the outer wall surface of the output shaft 20 and the inner wall surface of the cylinder body 10, and one end is adjacent to the first wear-resistant ring 81.

[0045] Preferably, the inner diameter of the first wear-resistant ring 81 is the same as the inner diameter of the first sleeve 25. This can not only fully utilize the space, but also increase the guide length, thereby improving the eccentric load capacity of the swing hydraulic cylinder 100.

[0046] According to one embodiment of the present invention, the swing hydraulic cylinder 100 further includes a second stopper 70, a second plane thrust needle roller bearing 90 and a second wear-resistant ring 91. The second stopper 70 is provided in the channel 11 and is located between the fixing member 50 and the end cover 30. The second stopper 70 cooperates with the first stopper 60 to limit the displacement of the output shaft 20 along its axial direction. The second plane thrust needle roller bearing 90 is provided between the second stopper 70 and the end cover 30. The second wear-resistant ring 91 is provided on the outer periphery of the second thrust needle roller bearing and is located between the second plane thrust needle roller bearing 90 and the cylinder body 10. The second wear-resistant ring 91 has high hardness, avoids wear of the inner hole of the cylinder barrel and is easy to replace.

[0047] In some specific embodiments of the present invention, the swing hydraulic cylinder 100 further includes a second sleeve 26, which is sleeved on the outer periphery of the output shaft 20 and located between the end cover 30 and the second wear-resistant ring 91. In other words, the second sleeve 26 is located between the outer wall surface of the end cover 30 and the inner wall surface of the cylinder body 10, and one end of the second sleeve 26 is adjacent to the second wear-resistant ring 91. The arrangement is simple and easy to install.

[0048] Furthermore, the inner diameter of the second wear-resistant ring 91 is the same as that of the second sleeve 26. The sleeve replaces the traditional guide ring, avoiding the need to provide a guide ring groove at the end cover 30, and the inner diameter of the second wear-resistant ring 91 is the same as that of the second sleeve 26, which can not only fully utilize the space and increase the guide length, but also improve the eccentric load capacity of the swing hydraulic cylinder 100.

[0049] Optionally, the swing hydraulic cylinder 100 further includes two gaskets, which are respectively arranged on both sides of the first plane thrust needle roller bearing 80 along the axial direction of the channel 11. By arranging the gaskets on both sides of the first plane thrust needle roller bearing 80, the interior of the first plane thrust needle roller bearing 80 is basically isolated from the outside. It can not only minimize the loss of various lubricating oils and grease substances added to the inside of the first plane thrust needle roller bearing 80, but also maintain the lubrication state of the first plane thrust needle roller bearing 80 to a large extent. It can also avoid the contact between the inside of the first plane thrust needle roller bearing 80 and various substances from the outside, reduce the probability of dust, harmful gases and other substances entering the inner cavity of the first plane thrust needle roller bearing 80, and reduce various damages caused by impurities inside the first plane thrust needle roller bearing 80, thereby extending the service life of the first plane thrust needle roller bearing 80.

[0050] According to an embodiment of the present invention, the first wear-resistant ring 81 is located at the outer periphery of the gasket. The first wear-resistant ring 81 has high hardness and can effectively prevent the gasket from being worn.

[0051] In some specific embodiments of the present invention, the outer wall surface of the output shaft 20 is provided with an annular step portion 23, and the first plane thrust needle roller bearing 80 is provided on the annular step portion 23. The first stopper 60 can be fixedly connected to the cylinder body 10 by a set screw, which can effectively prevent the rotation of the first stopper 60. When the output shaft 20 and the end cover 30 rotate, the output shaft 20 and the end cover 30 will produce relative rotation with the first stopper 60 and the second stopper 70. In order to reduce friction, a bearing is added between the two, and the step portion 23 can play a good supporting role for the first plane thrust needle roller bearing 80.

[0052] In summary, the swing hydraulic cylinder 100 according to the embodiment of the present invention adopts a structure in which the first sleeve 25, the second sleeve 26, the first wear-resistant ring 81, and the second wear-resistant ring 91 cooperate with each other, which not only increases the degree of guidance and improves the overload capacity of the swing hydraulic cylinder 100, but also avoids wear of the inner hole of the cylinder body 10, thereby extending the service life of the swing hydraulic cylinder 100.

[0053] Other structures and operations of the swing hydraulic cylinder according to the embodiment of the present invention are understandable and easy to implement for those skilled in the art, and thus will not be described in detail.

[0054] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0055] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A swing hydraulic cylinder, It is characterized in that include: A cylinder body, wherein a passage extending along the axial direction of the cylinder body is defined therein; an output shaft, at least a portion of which is disposed in the channel and extends along the axial direction of the channel, and at least a portion of an outer wall surface of the output shaft is spaced apart from an inner wall surface of the channel; An end cover, which is disposed at one end of the channel and connected to the output shaft; A piston, the piston is located in the channel and divides the channel into a first chamber and a second chamber spaced apart from each other, the cylinder body is provided with a first oil delivery hole communicated with the first chamber and a second oil delivery hole communicated with the second chamber, the piston is sleeved on the outer periphery of the output shaft and can reciprocate along the axial direction of the channel under the action of the pressure oil in the first chamber and the second chamber, at least a portion of the inner wall surface of the piston forms a first spiral pair with the outer wall surface of the output shaft, and at least a portion of the outer wall surface of the piston is spaced apart from the inner wall surface of the channel; A fixing member, the fixing member is disposed in the channel and is located between the outer wall surface of the piston and the inner wall surface of the channel in the radial direction of the channel and forms a second helical pair with the outer wall surface of the piston in a rotation direction opposite to that of the first helical pair; a first stopper, the first stopper being arranged in the passage and between one end of the output shaft and the first oil delivery hole; A first plane thrust needle roller bearing, wherein the first plane thrust needle roller bearing is arranged between the first stopper and one end of the output shaft; a first wear-resistant ring, which is arranged on the outer periphery of the first planar thrust needle roller bearing and is located between the first planar thrust needle roller bearing and the cylinder body; Also includes: A first sleeve, the first sleeve being sleeved on the outer circumference of the output shaft and being located between one end of the output shaft and the first wear-resistant ring; a second limiting member, the second limiting member being arranged in the channel and between the fixing member and the end cover, the second limiting member cooperating with the first limiting member to limit the displacement of the output shaft along the axial direction thereof; A second planar thrust needle roller bearing, wherein the second planar thrust needle roller bearing is disposed between the second stopper and the end cover; a second wear-resistant ring, the second wear-resistant ring being arranged on the outer periphery of the second planar thrust needle roller bearing and being located between the second planar thrust needle roller bearing and the cylinder body; A second sleeve is sleeved on the outer periphery of the output shaft and is located between the end cover and the second wear-resistant ring.

2. The swing hydraulic cylinder according to claim 1, It is characterized in that The inner wall surface of the first planar thrust needle roller bearing abuts against the outer wall surface of the output shaft, and the outer wall surface of the first planar thrust needle roller bearing abuts against the wear-resistant ring.

3. The swing hydraulic cylinder according to claim 1, It is characterized in that The first wear-resistant ring has the same inner diameter as the first sleeve.

4. The swing hydraulic cylinder according to claim 1, It is characterized in that The second wear-resistant ring and the second sleeve have the same inner diameter.

5. The swing hydraulic cylinder according to claim 1, It is characterized in that Also includes: Two gaskets are respectively arranged on both sides of the first planar thrust needle roller bearing along the axial direction of the channel.

6. The swing hydraulic cylinder according to claim 5, It is characterized in that The first wear-resistant ring is located on the outer periphery of the gasket.

7. The swing hydraulic cylinder according to claim 1, It is characterized in that An annular step portion is provided on the outer wall surface of the output shaft, and the first planar thrust needle roller bearing is provided on the annular step portion.

Images