JP2017053106A - Protective structure for cylinder and work machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a protective structure for a cylinder that suppresses a cover member from interfering with a member fitted to an outer periphery of a cylinder tube without increasing the number of components.SOLUTION: A cylinder 5 comprises a cylinder tube 51, a rod 53, a cover support member 7, and a protective cover 6. The protective cover 6 has one end side 6A constituted as a fixed end which is fixed to a tip part of the rod 53 and the other end side 6B constituted as a free end which is not fixed. Parts between the one end side 6A and the other end side 6B of the protective cover 6 abut slidably on the cover support member 7, and function as a pair of rail parts 63A, 63B guiding the cover member to slide in an expansion/contraction direction D1. At an end side of the other end side 6B of the protective cover 6, a cut part 61 is formed which avoids interference with a fitting member fitted to an outer peripheral surface of the cylinder tube 51 during contraction of the rod 53.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a protection structure for a cylinder and a technology related to the structure.

  2. Description of the Related Art Conventionally, in a working machine, a cover is provided on a hydraulic cylinder to prevent earth and sand or rocks from colliding with a rod portion. For example, in patent document 1, the boom cylinder (3) provided with the protection apparatus (2) for rods is disclosed.

  Specifically, an outer rail cover (32) and an inner rail cover (35) divided into two parts are provided as protective covers for the rod (29). When the boom cylinder (3) is extended, the two rail covers (32, 35) are connected to each other to be in an extended state. On the other hand, when the boom cylinder (3) is reduced, the inner rail cover (35) is 32) It will be in an accommodation state. According to this invention, it can prevent that a cover interferes with the member provided in the outer periphery of the cylinder cylinder of a hydraulic cylinder.

Japanese Patent No. 3587597

  However, in the split type cover described in Patent Document 1, since the number of parts is increased, the configuration of the entire cylinder device is complicated, and the work efficiency during assembly is reduced.

  Therefore, an object of the present invention is to provide a cylinder protection structure that suppresses interference of a cover member with a member attached to the outer periphery of a cylinder tube without increasing the number of parts.

  In order to achieve the above object, the present invention is a cylinder protection structure comprising a cylinder tube and a rod projecting from the tip of the cylinder tube so as to expand and contract, and is provided on the rod side of the cylinder tube. A support member and a cover member that is long in the direction of expansion and contraction of the rod, wherein one end side is configured as a fixed end that is fixed to the tip portion of the rod and the other end side is configured as a free end that is not fixed A part between the one end side and the other end side of the cover member is slidably supported by the support member, and guides the sliding of the cover member in the expansion / contraction direction An attachment member that is attached to the outer peripheral surface of the cylinder tube when the rod is contracted, on the end side of the other end side of the cover member. It provides a protective structure for a cylinder, wherein a cutout portion for avoiding interference is formed.

  Moreover, it is preferable that the said supporting member is arrange | positioned in the position which blocks at least one part of the said notch part in the state which the said rod extended | stretched.

  Moreover, it is preferable that the said supporting member is comprised as a flat plate which has an area larger than the said notch part, and is arrange | positioned in the position which plugs up the said notch part in the state which the said rod extended | stretched.

  Further, the guide portion includes a pair of rail portions extending in the expansion / contraction direction of the rod at both ends parallel to the expansion / contraction direction of the cover member, and the protective surface of the cover member includes the pair of rail portions. It is preferable that a stepped portion that is recessed toward the cylinder side from the one end side to the other end side is formed.

  The cylinder tube is provided with a pipe extending in the expansion / contraction direction, and the cover member is fixed to the first cover and a first cover disposed at a position to protect the rod when the rod is extended. And a second cover that is configured to move together with the first cover and that is disposed at a position that protects the pipe when the rod is contracted, and an end on the other end side of the second cover Preferably, the notch is formed so as to avoid interference with the mounting member when the rod is contracted.

  The present invention is a work machine, comprising a machine main body, an attachment connected to the machine main body, and a cylinder that rotates the attachment. The cylinder includes a cylinder tube, and a cylinder tube. A rod that protrudes from the tip of the rod, a support member provided on the rod side of the cylinder tube, and a cover member that is long in the direction of stretching of the rod, one end of which is fixed to the tip of the rod And a cover member configured as a free end that is not fixed at the other end, and a part between one end and the other end of the cover member is slidable on the support member The guide member functions as a guide portion that guides the sliding of the cover member in the expansion and contraction direction. And further provides a working machine, wherein a cutout portion for avoiding interference with the member at the time of de contraction is attached to the outer peripheral surface of the cylinder tube is formed.

  According to the present invention, the cover member for protecting the rod is constituted by one member, and the notch is formed on the end side on the other end side of the cover member. For this reason, when the rod is contracted, a part of the attachment member attached to the outer peripheral surface of the cylinder tube is disposed in the notch. Therefore, it is possible to prevent the cover member from interfering with the attachment member attached to the outer periphery of the cylinder tube without increasing the number of parts.

1 is a side view showing a hydraulic excavator according to a first embodiment of the present invention. The side view which shows the attachment of a hydraulic shovel. The perspective view which shows the cylinder and protective cover of a rod's most contracted state (A) and the most extended state (B). The perspective view which shows a protective cover and a cover support member. VV position sectional drawing of FIG. 3 (B). The side view (A) and top view (B) which show the cylinder and protection cover of the rod most extended state. The side view (A) and top view (B) which show the cylinder and protective cover of the rod most contracted state. VIII-VIII position sectional drawing of FIG. 7 (A). The top view which shows the protective cover and cover support member of a rod maximum extension state. The side view which shows a lower traveling body provided with the dozer apparatus which concerns on 2nd Embodiment. The top view which shows the lower frame and dozer device of a lower traveling body. The figure which shows the state change of the dozer blade according to the expansion-contraction of an angle cylinder. The perspective view which shows the angle cylinder of the state which removed the cover member. The side view which shows the angle cylinder in the expansion | extension state. The side view which shows the angle cylinder in a contracted state. The perspective view which shows a 1st protective cover and a 2nd protective cover. The top view of the cylinder and protective cover which concern on a modification.

<1. First Embodiment>
A cylinder protection structure according to a first embodiment of the present invention will be described with reference to FIGS. Hereinafter, a hydraulic excavator 10 will be described as an example of a work machine according to the present invention.

  As shown in FIG. 1, the hydraulic excavator 10 includes a crawler type lower traveling body 20 and an upper swing body 30.

  The upper turning body 30 is mounted on the lower traveling body 20 and can turn around the vertical axis with respect to the lower traveling body 20. The upper swing body 30 includes a machine main body 40 and an attachment 1 connected to the machine main body 40.

  As shown in FIG. 2, the attachment 1 includes a boom 2, an arm 3, a bucket 4, and the like, and is used by being attached to a machine main body 40 (FIG. 1). A boom cylinder 5 for raising and lowering the boom 2 is mounted on the boom 2. The boom cylinder 5 is an example of a cylinder according to the present invention.

  As shown in FIG. 3, the boom cylinder 5 includes a cylinder tube 51 and a rod 53 that protrudes from a head cover 51 </ b> H provided at the tip of the cylinder tube 51 so as to extend and contract. The boom cylinder 5 is provided with a protective cover 6 that protects the rod 53 from earth and sand and rocks scattered during excavation work and the like. The protective cover 6 is an example of a cover member according to the present invention.

  Hereinafter, the protection structure of the boom cylinder 5 will be described in detail with reference to FIGS.

  As shown in FIG. 3B, a cover support member 7 for slidably supporting the protective cover 6 is provided on the outer peripheral surface of the cylinder tube 51 on the rod 53 side. As shown in FIG. 4, the cover support member 7 is configured by a flat plate that can be inserted inside the protective cover 6. The cover support member 7 is an example of a support member according to the present invention.

  As shown in FIGS. 3A and 3B, the protective cover 6 is composed of a plate-like member that is long in the expansion / contraction direction D <b> 1 of the rod 53. Of the protective cover 6, one end side 6 </ b> A is configured as a fixed end fixed to the distal end portion of the rod 53 by a bolt, and the other end side 6 </ b> B is configured as a free end that is not fixed. With this configuration, as shown in FIGS. 3A and 3B, when the rod 53 is expanded and contracted with respect to the cylinder tube 51, the protective cover 6 moves together with the rod 53. As shown in FIGS. 3A and 3B and FIG. 4, a cutout portion 61 is formed on the end side of the other end side 6 </ b> B of the protective cover 6. The notch 61 will be described in detail later.

  Further, the protective cover 6 includes a pair of rail portions 63A and 63B extending in the expansion / contraction direction D1 at both ends parallel to the expansion / contraction direction D1. As shown in FIG. 5, each of the rail portions 63A and 63B has a substantially U-shaped cross section. A part of the U-shaped inner side of the rail parts 63A and 63B slidably contacts the cover support member 7 and functions as a guide part that guides the sliding (sliding movement) of the protective cover 6 in the expansion / contraction direction D1.

  As shown in FIGS. 3A, 3 </ b> B, and 5, a stepped portion 65 is formed on the protective surface of the protective cover 6 (surface facing away from the boom cylinder 5). The step portion 65 is a portion that is recessed toward the boom cylinder 5 from the one end side 6A to the other end side 6B between the pair of rail portions 63A, 63B. In addition, inclined portions 67A and 67B exist between the pair of rail portions 63A and 63B and the stepped portion 65. The notch 61 is formed only in a part of the step 65 in the protective cover 6. That is, the notch 61 is not formed in the rail parts 63A and 63B and the inclined parts 67A and 67B.

  As shown in FIGS. 6 and 7, in the first embodiment, a holding valve (oil-tight holding function valve) 8 is provided on the outer periphery of the base end side of the cylinder tube 51. As shown in FIG. 8, a part (bracket 81) of the holding valve 8 is disposed in a notch 61 formed in the protective cover 6 when the rod 53 is contracted to the minimum. If the notch 61 is not formed at the end of the other end side 6B, the protective cover 6 interferes with the holding valve 8 when the rod 53 is fully contracted (see FIG. 7). The holding valve 8 is an example of a mounting member according to the present invention.

  Also, as shown in FIG. 9, the cover support member 7 is configured as a flat plate having a larger area than the notch 61. The cover support member 7 is disposed at a position that closes the notch 61 when the rod 53 is fully extended. As shown in FIG. 4, in the cover support member 7, the left and right side portions 73A and 73B (portions corresponding to the rail portions 63A and 63B) are formed longer in the D1 direction than the center portion 73C. Therefore, as shown in FIG. 9, the overlapping part of the cover support member 7 and the protective cover 6 can be enlarged.

  In the first embodiment, the protective cover 6 for protecting the rod 53 is constituted by a single plate member, and a notch 61 is formed on the end side of the other end side 6B. A part of the holding valve 8 (bracket 81) is disposed in the notch 61 when the rod 53 is fully contracted. Therefore, it is possible to prevent the protective cover 6 from interfering with the holding valve 8 without increasing the number of parts.

  Moreover, in 1st Embodiment, the cover support member 7 is arrange | positioned in the position which plugs up the notch part 61 at the time of the maximum extension of the rod 53 (FIG. 9). Therefore, it is not necessary for earth and sand or rocks to enter the rod 53 side through the notch 61, and the rod 53 can be reliably protected as in the conventional case. Further, since the cover support member 7 is configured as a flat plate having an area larger than that of the notch portion 61, a portion where the protective cover 6 and the cover support member 7 overlap (a broken line portion in FIG. 9) is relatively large. The As a result, the load when earth, sand, rocks or the like collide with the protective cover 6 is dispersed, and deformation or breakage of the protective cover 6 can be prevented.

  As shown in FIGS. 3 and 5, a stepped portion 65 is formed between the pair of rail portions 63 </ b> A and 63 </ b> B on the protective surface of the protective cover 6. Therefore, the protective cover 6 is provided with a bending structure in which the boom cover 5 is recessed, and the rigidity of the protective cover 6 is improved.

  Further, in the first embodiment, as shown in FIG. 3A, the notch portion 61 is formed in a part of the step portion 65. In other words, the notch 61 is not formed in the rails 63A and 63B or the inclined parts 67A and 67B. Therefore, when the rod 53 is fully extended, the notch 61 can be closed without gaps by the cover support member 7, and intrusion of earth and sand or rocks can be more reliably prevented.

<2. Second Embodiment>
In the first embodiment, the boom cylinder 5 has been described as an example of the cylinder according to the present invention. On the other hand, 2nd Embodiment demonstrates taking the angle cylinder which comprises a dozer apparatus as an example of the cylinder which concerns on this invention. In the second embodiment, the description of the same parts as those in the first embodiment is omitted.

  In 2nd Embodiment, as shown in FIG. 10, the lower traveling body 20 is provided with the dozer apparatus 9 used for dozer work.

  As shown in FIG. 11, the dozer device 9 includes a pair of left and right arms 91, a dozer cylinder 93, a dozer blade 95, and an angle cylinder 97.

  The arm 91 is a member for connecting the lower frame 21 of the lower traveling body 20 and the dozer blade 95. Among the arms 91, the rear end portion is connected to a fulcrum portion 23 provided on the lower frame 21, and the front end portion is connected to a dozer blade 95.

  The dozer cylinder 93 is a cylinder for rotating the arm 91 in the vertical direction D2 shown in FIG.

  The dozer blade 95 is a soil discharge plate for extruding earth and sand in the traveling direction of the excavator 10.

  As shown in FIG. 12, the angle cylinder 97 is a cylinder for changing the horizontal inclination of the dozer blade 95 by expansion and contraction.

  As shown in FIG. 13, the angle cylinder 97 includes a cylinder tube 971 and a rod 973 that protrudes from the tip of the cylinder tube 971 so as to extend and contract.

  The cylinder tube 971 is provided with an oil supply port 98A for supplying hydraulic oil to the bottom chamber via a connector 981A. The cylinder tube 971 is provided with a pipe 96 extending in the axial direction of the angle cylinder 97, and an oil supply port 98B for supplying hydraulic oil to the rod chamber via the pipe 96 is provided via the connector 981B. It has been.

  When hydraulic oil is supplied to the bottom chamber via the oil supply port 98A, the rod 973 extends. On the other hand, when hydraulic oil is supplied to the rod chamber through the oil supply port 98B and the pipe 96, the rod 973 contracts.

  Further, a cover support member 94 for slidably supporting a cover member 99 (FIGS. 14 to 16) described below is attached to the cylinder tube 971 using a band 92. The cover support member 94 includes a sliding surface 94A that is slidably in contact with the cover member 99 described below, and a connection portion 94C that connects the sliding surface 94A and the outer periphery of the cylinder tube 971.

  The cover member 99 includes a first protective cover 991 that protects the rod 973 when extended as shown in FIG. 14, and a second protective cover 993 that protects the pipe 96 when contracted as shown in FIG.

  As shown in FIG. 16, the first protective cover 991 has a cylindrical shape into which the rod 973 can be inserted. On the other hand, the second protective cover 993 has a U-shaped cross section through which the pipe 96 can be inserted. The second protective cover 993 is welded to the outer peripheral surface of the first protective cover 991.

  An end 991E (FIGS. 14 and 15) on the rod 973 side of the first protective cover 991 is connected to the tip of the rod 973 via a bolt. On the other hand, the end opposite to the end 991E is not fixed and is configured as a free end. Accordingly, the first protective cover 991 moves following the expansion and contraction of the rod 973 (see FIGS. 14 and 15).

  As shown in FIG. 14, when the rod 973 is extended, the first protective cover 991 surrounds and protects the rod 973. On the other hand, as shown in FIG. 15, when the rod 973 is contracted, the first protective cover 991 is retracted to a position surrounding the outer peripheral surface of the cylinder tube 971. Therefore, the first protective cover 991 has a larger diameter than the cylinder tube 971.

  As shown in FIGS. 14 to 16, the second protective cover 993 has a notch 993 </ b> A formed on the base end side of the angle cylinder 97. Since the second protective cover 993 is connected to the outer peripheral surface of the first protective cover, it moves together with the first protective cover.

  As shown in FIG. 14, when the rod 973 is extended, a part of the notch 993 </ b> A of the second protective cover 993 is blocked by the sliding surface 94 </ b> A of the cover support member 94.

  On the other hand, as shown in FIG. 15, the second protective cover 993 is disposed at a position that protects the pipe 96 when the rod 973 is contracted. At this time, the connector 981B, which is a connection portion between the oil supply port 98B and the cylinder tube 971, is disposed in the notch 993A of the second protective cover 993. The connector 981B is an example of an attachment member according to the present invention.

  As described above, in the second embodiment, the cutout portion 993A is formed in the second protective cover 993 of the cover member 99. When the rod 973 is contracted to the minimum, a connector 981B, which is a connection portion between the oil supply port 98B and the cylinder tube 971, is disposed in the notch 993A. That is, the presence of the notch 993A prevents interference between the second protective cover 993 and the connector 981B. Therefore, it is possible to prevent the second protective cover 993 from interfering with the connector 981B without increasing the number of parts.

<3. Modification>
The cylinder protection structure according to the present invention is not limited to the above-described embodiment, and various modifications and improvements can be made within the scope described in the claims.

  In the said 1st Embodiment, although the holding valve 8 was illustrated as an example of the attachment member attached to the base end side outer periphery of the cylinder tube 51, it is not limited to this. For example, as shown in FIG. 17, the same effect as that of the above embodiment can be obtained also when the port 80 connecting the pipes is provided on the outer periphery on the proximal end side of the cylinder tube 51.

  Moreover, although the case where the step part 65 was formed in the protective surface of the protective cover 6 was illustrated in the said embodiment, it is not limited to this, It is comprised so that a protective surface may be comprised with the flat shape which does not have the step part 65. It may be.

  In addition, as an example of the cylinder according to the present invention, the boom cylinder 5 is illustrated in the first embodiment, and the angle cylinder 97 is illustrated in the second embodiment. However, the present invention is not limited to this, and other cylinders mounted on the work machine are exemplified. The present invention can also be applied to a cylinder.

  In the first embodiment, the case where a part of the holding valve 8 (the bracket 81) is disposed in the notch 61 when the rod 53 is contracted is illustrated. There is no need. For example, the rod 53 may be in a slightly extended side than when it is fully contracted.

  Similarly, in the second embodiment, the case where the connector 981B is disposed in the notch 993A when the rod 973 is contracted is illustrated, but the rod 973 is not necessarily required to be contracted.

  In the first embodiment, the case where the cover support member 7 is disposed at a position that closes the notch 61 when the rod 53 is extended to the maximum is illustrated. However, the rod 53 is not necessarily extended to the maximum extension. Absent. For example, the rod 53 may be in a slightly contracted side with respect to the maximum extension.

  As described above, the configuration according to the present invention is suitable for use in a hydraulic excavator or the like equipped with a hydraulic cylinder having a protective cover.

1 Attachment 2 Boom 3 Arm 4 Bucket 5 Boom cylinder
6 protective cover, 6A one end side, 6B other end side, 7 cover support member,
8 Holding valve, 9 Dozer device, 10 Hydraulic excavator, 20 Lower traveling body,
21 Lower frame, 23 fulcrum, 30 upper swing body, 40 machine body,
51 cylinder tube, 51H head cover, 53 rod, 61 notch,
63A, 63B rail part, 65 step part, 67A, 67B inclined part,
73A, 73B left and right side parts, 73C center part, 80 ports, 81 bracket,
91 arm, 92 band, 93 dozer cylinder, 94 cover support member,
94A sliding surface, 94C connection, 95 dozer blade, 96 piping,
97 Angle cylinder, 98A, 98B Filling port, 99 Cover member,
971 Cylinder tube, 973 rod, 991 first protective cover, 991E end,
993 Second protective cover, 993A Notch, D1 Stretch direction, D2 Vertical direction

Claims (6)

A cylinder protection structure comprising a cylinder tube and a rod projecting from the tip of the cylinder tube so as to expand and contract,
A support member provided on the rod side of the cylinder tube;
A cover member that is long in the direction of expansion and contraction of the rod, wherein one end side is configured as a fixed end fixed to the tip of the rod and the other end side is configured as a free end that is not fixed;
With
A part between the one end side and the other end side of the cover member is slidably supported by the support member, and functions as a guide portion that guides the sliding of the cover member in the expansion and contraction direction.
A notch for avoiding interference with an attachment member attached to the outer peripheral surface of the cylinder tube when the rod is contracted is formed on the end side of the other end side of the cover member. Feature cylinder protection structure.   2. The cylinder protection structure according to claim 1, wherein the support member is disposed at a position that closes at least a part of the notch in a state where the rod is extended. 3.   3. The cylinder according to claim 2, wherein the support member is configured as a flat plate having a larger area than the notch, and is disposed at a position that closes the notch when the rod is extended. Protection structure. The guide portion includes a pair of rail portions extending in the expansion / contraction direction of the rod on both ends parallel to the expansion / contraction direction of the cover member,
4. A stepped portion is formed on the protective surface of the cover member, the step being recessed toward the cylinder from the one end side to the other end side between the pair of rail portions. The cylinder protective structure as described in any one of them. The cylinder tube is provided with a pipe extending in the expansion / contraction direction,
The cover member is
A first cover disposed at a position to protect the rod when the rod is extended;
A second cover fixed to the first cover and configured to move together with the first cover, and disposed at a position to protect the pipe when the rod is contracted;
Have
3. The notch for avoiding interference with the mounting member when the rod is contracted is formed at an end of the second cover on the other end side. Cylinder protection structure. A working machine,
The machine body,
An attachment connected to the machine body;
A cylinder for rotating the attachment;
With
The cylinder is
A cylinder tube;
A rod projecting from the tip of the cylinder tube so as to expand and contract;
A support member provided on the rod side of the cylinder tube;
A cover member that is long in the direction of expansion and contraction of the rod, wherein one end side is configured as a fixed end fixed to the tip of the rod and the other end side is configured as a free end that is not fixed;
Have
A part between one end and the other end of the cover member is slidably supported by the support member, and functions as a guide portion that guides the sliding of the cover member in the expansion and contraction direction.
A notch for avoiding interference with a member attached to the outer peripheral surface of the cylinder tube when the rod is contracted is formed at the end of the cover member on the other end side. Work machine.

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