JPH11241362A - Bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve compactness of a bearing device, and improve assembling workability by rotatably connecting a boss member to a bracket member without using a connection pin. SOLUTION: A lower boom 7, and an upper boom 9 are provided on a work device 6 of a hydraulic back hoe. On a lower boom bracket 18, an installation plate 20 is detachably installed using installation bolts 22, and on an upper boom boss 19, an installation plate 23 is detachably installed using installation bolts 25. A protruded part 24 of the installation plate 23 is slidably fitted into an fitting recess 21 in the installation plate 20, thereby the lower boom 7 and the upper boom 9 are horizontally rotatably connected to each other by a bearing device 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing device suitable for use in a working device mounted on a construction machine such as a hydraulic shovel.

[0002]

2. Description of the Related Art Generally, a working device mounted on a construction machine such as a hydraulic excavator is provided with a bearing device for rotatably connecting a boom, an arm, a bucket, and the like. This kind of conventional bearing device is provided with a pair of bracket members provided to face each other and connected between the respective bracket members, as shown in, for example, Japanese Utility Model Application Laid-Open No. 5-96152. And a boss member rotatably connected to each bracket member via a pin.

In this case, a pin insertion hole for a connecting pin is formed in the bracket member and the boss member. The connecting pin is inserted at both ends in the axial direction into the pin insertion holes of the bracket member, protrudes to the outside of the bracket member through the pin insertion holes, and has one end portion with a retaining pin or the like. It is fixed to the outer surface side of the bracket member in a state where the bracket is prevented from coming off and rotating. Further, the connection pin is slidably inserted into a pin insertion hole of the boss member via a bush or the like at an intermediate portion in the axial direction, thereby rotatably connecting the bracket and the boss member.

[0004]

In the prior art described above, both ends of the connecting pin are projected outward from the bracket member, and one end of the connecting pin is prevented from coming off on the outer surface side of the bracket member by a retaining pin or the like. Since it is configured to be fixed in a detented state, the external dimensions of the bearing device become large, especially in the axial direction of the connecting pin, and there is a problem that it is difficult to reduce the size of the bearing device.

[0005] Further, since the connecting pin is formed as a heavy column made of a high-strength metal material or the like, when assembling the working device of the excavator, the boom, the arm and the like are connected using the heavy connecting pin. Therefore, not only the workability at the time of assembling deteriorates, but also the weight of the working device increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and the present invention is capable of securely connecting a bracket member and a boss member without using a connecting pin or the like, thereby achieving a reduction in size and weight. It is an object of the present invention to provide a bearing device capable of efficiently performing assembly work.

[0007]

According to a first aspect of the present invention, there is provided a bearing device in which a boss member is rotatably connected between a pair of bracket members. One of the boss members is provided with a pair of convex portions serving as a rotation axis, and the other member is provided with a pair of fitting concave portions into which the convex portions are rotatably fitted. Features a characteristic configuration.

[0008] With this configuration, the protrusion provided on one of the bracket member and the boss member can be slidably fitted into the fitting recess provided on the other member. The bracket member and the boss member can be rotatably connected via the convex portion and the fitting concave portion.

According to the second aspect of the present invention, the one member has a detachable mounting plate having the projection, and the other member has another mounting plate having the fitting recess. Is provided.

Thus, when assembling the bearing device, first, the other mounting plate is attached to one of the mounting plates attached to the boss member so that the convex portion and the fitting concave portion are fitted to each other. The member and each mounting plate can be disposed between each bracket member. Then, by attaching the other mounting plate to the bracket member, the mounting plate can be fixed to the bracket member and the bob member in a state where the respective mounting plates are fitted to each other, and the bearing device can be easily assembled.

In the invention according to claim 3, at least one of the mounting plate having the convex portion and the mounting plate having the fitting concave portion is formed of a self-lubricating material.

Thus, when the boss member is relatively rotated with respect to the bracket member, the convex portion and the fitting concave portion of each mounting plate can be smoothly slid between them.

Further, in the invention according to claim 4, the bracket member or the boss member is provided with a shim plate located between the bracket member and the boss member.

Thus, the gap between the mounting plate of the bracket member and the mounting plate of the boss member can be adjusted by the thickness of the shim plate.

[0015] In the invention of claim 5, the lower boom, an upper boom rotatably provided on the lower boom via a bearing, and an arm stay rotatably provided on the upper boom via a bearing, The present invention is applied to a working device of a construction machine including an arm provided on the arm stay so as to be able to move up and down.

Thus, for example, a bearing provided on a lower boom, an upper boom, an arm stay and the like of the working device is constituted by the bearing device of the present invention, so that the working device can be downsized.
The weight can be reduced.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below in detail with reference to FIGS.

FIGS. 1 to 4 show a first embodiment of the present invention. In this embodiment, a case where a bearing device is applied to a hydraulic shovel will be described as an example.

Reference numeral 1 denotes an undercarriage constituting the lower side of the hydraulic excavator, and 2 denotes an upper revolving body mounted on the undercarriage 1 so as to be pivotable. The upper revolving body 2 includes a machine room 3 and a driver's cab. 4 and a counterweight 5 are provided.

Reference numeral 6 denotes a working device mounted on the upper revolving unit 2 so as to be able to move up and down for performing an excavating operation and the like.
Is composed of a lower boom 7, an upper boom 9, an arm stay 11, an arm 13, a bucket 15, and the like, which will be described later.

Reference numeral 7 denotes a lower boom whose base end is pin-connected to the upper revolving unit 2 so as to be able to move up and down. A lower boom bracket 18 to be described later is integrally provided at the distal end of the lower boom 7. The lower boom 7 is raised and lowered by a boom cylinder 8 disposed between the lower boom 7 and the upper swing body 2.

An upper boom 9 is rotatably connected to the distal end of the lower boom 7 using a bearing device 17 described later.
As shown in FIG. 2, an upper boom boss 19 described later is integrally provided on the base end side of the upper boom 9. Then, the upper boom 9 is rotated left and right with respect to the lower boom 7 in the direction of arrow A in FIG. 2 by an offset cylinder 10 disposed between the upper boom 9 and the lower boom 7.

An arm stay 11 is rotatably connected to the distal end of the upper boom 9 using a bearing device 26 described later. The arm stay 11 is connected to the lower boom 7 as shown in FIGS. A bar-shaped link 12 is provided between them. When the upper boom 9 rotates left and right with respect to the lower boom 7, the arm stay 1
1 is rotated in the opposite direction with respect to the upper boom 9 by the rod-shaped link 12 and the like, and rotates left and right in the direction of arrow C in FIG. Thereby, the bar-shaped link 12 is connected to the upper boom 9,
The arm 13 and the like are always kept parallel to the lower boom 7.

An arm 13 is pin-connected to the tip of the arm stay 11 so as to be able to move up and down. The arm 13 is moved up and down with respect to the arm stay 11 by an arm cylinder 14. Reference numeral 15 denotes a bucket pin-connected to the tip end of the arm 13 so as to be rotatable upward and downward. The bucket 15 is vertically rotated with respect to the arm 13 by a bucket cylinder 16 to excavate earth and sand. Work.

Reference numeral 17 denotes a bearing device according to the present embodiment in which the lower boom 7 and the upper boom 9 are rotatably connected to the left and right directions. The bearing device 17 is, as shown in FIG. , 18, an upper boom boss 19, a mounting plate 20 having a fitting recess 21,
4 and the like.

Reference numerals 18 and 18 denote a pair of lower boom brackets as bracket members provided on the distal end side of the lower boom 7, and the lower boom bracket 18 is a metal member which is arranged to be separated upward and downward in FIG. It is made of a plate or the like, and is provided with bolt insertion holes for mounting bolts 22 described later.

Reference numeral 19 denotes an upper boom boss as a boss member provided on the base end side of the upper boom 9. The upper boom boss 19 is disposed between the lower boom brackets 18 and faces the lower boom brackets 18. The mounting plate 23 is provided on the upper and lower sides of the upper boom boss 19 to be mounted.
19A for mounting and screw holes 19 for mounting bolts 25
B are formed respectively.

Reference numerals 20 and 20 denote each lower boom bracket 18.
A pair of upper and lower mounting plates provided on the
As shown in FIGS. 3 and 4, a high-strength metal material having a self-lubricating property, such as a copper alloy, or a high-strength metal having a self-lubricating material, such as polytetrafluoroethylene, on a sliding surface is used. It is formed in a substantially disk shape by a material, and is arranged on the inner surface side of each lower boom bracket 18 facing each other. An annular projection 20A is integrally formed at the center of the inner surface side of the mounting plate 20, and a pair of fittings which slidably fit the respective projecting portions 24 of the mounting plate 23 on the inner peripheral side of each of the projections 20A. The concave portions 21 and 21 are formed. Furthermore, mounting plate 2
2, screw holes 20B for screwing the mounting bolts 22 in FIG. 2 are formed at intervals in the circumferential direction of the projection 20A.

In each screw hole 20B of the mounting plate 20, for example, four mounting bolts 22 are screwed through respective bolt insertion holes of the lower boom bracket 18. Thus, each mounting plate 20 is removably fastened to the inner surface of each lower boom bracket 18.

Reference numerals 23, 23 are in sliding contact with the respective mounting plates 20.
In the lower pair of mounting plates, the mounting plate 23 is shown in FIGS.
As shown in the figure, the mounting plate 20 is formed in a substantially disc shape from a high-strength metal material having self-lubricating properties almost similarly to the mounting plate 20. An annular groove 23A is formed at a central portion of the mounting plate 23 with a certain depth dimension, and bolt insertion holes for mounting bolts 25 are drilled at intervals in a circumferential direction on a bottom side thereof. Further, the inner peripheral side of the annular groove 23A constitutes a pair of convex portions 24, 24 located on the upper surface side and the lower surface side of the upper boom boss 19 and arranged coaxially with each other.
4 is slidably fitted in the fitting concave portion 21 of the mounting plate 20, and is positioned in the radial direction by the projection 20A of the mounting plate 20.

Here, four mounting bolts 25, such as hexagon socket bolts, are inserted into the respective bolt insertion holes of the mounting plate 23, and each of the mounting bolts 25 has a distal end corresponding to each of the upper boom bosses 19. It is screwed into the screw hole 19B. Thereby, each mounting plate 23 is connected to the upper boom boss 1.
Nine recesses 19A are detachably fastened.

When the upper boom 9 rotates left and right with respect to the lower boom 7 in the directions indicated by arrows A in FIG. 2, the mounting plate 23 moves relative to the mounting plate 20 in directions indicated by arrows B in FIG. The projection 24 rotates in the fitting recess 21 at this time. As a result, each projection 24 constitutes a rotation axis of the bearing device 17.

26 is an upper boom 9 and an arm stay 11
As shown in FIG. 1, the bearing device 26 includes, for example, a boss portion provided on the distal end side of the upper boom 9 and the arm stay 11 in substantially the same manner as the bearing device 17 described above. A pair of bracket portions provided on the base end side, a pair of mounting plates detachably attached to the boss portion and having a convex portion, and detachably attached to each bracket portion, and each of the convex portions is And another mounting plate (both not shown) having a pair of fitting recesses to be slidably fitted.

The bearing device 26 connects the upper boom 9 and the arm stay 11 so as to be rotatable left and right, and the arm stay 11 is connected to the upper boom 9 by an arrow C in FIG.
It is allowed to turn left and right in the direction.

The hydraulic shovel according to the present embodiment has the above-described configuration, and its operation will be described next.

First, during operation of the hydraulic excavator, the lower boom 7 is moved together with the upper boom 9 and the arm stay 11 to the upper revolving unit 2 by operating the boom cylinder 8, the arm cylinder 14, the bucket cylinder 16 and the like of the working device 6. The excavation work such as earth and sand is performed by rotating the arm 13, the bucket 15, and the like on the tip side of the upper boom 9 while raising and lowering the same.

When excavating a gutter on the right side of the upper revolving unit 2 (vehicle), when the offset cylinder 10 is extended, each convex portion 24 of the bearing device 17 rotates in each fitting concave portion 21 and the upper boom 9 Is indicated by a solid line in FIG.
It rotates to the right side of the lower boom 7 via the bearing device 17.

As a result, the arm stay 11 is pivoted to the left side of the upper boom 9 via the bearing device 26 by the rod-like link 12 or the like, and the arm 13 is moved to the right with respect to the lower boom 7. 7, side grooves are dug by rotating (elevating) the arm 13, the bucket 15, and the like. Further, when digging a side ditch on the left side of the vehicle, the upper boom 9 is rotated to the left side of the lower boom 7 as shown by a two-dot chain line in FIG. 2 by reducing the offset cylinder 10.

On the other hand, when connecting the lower boom 7 and the upper boom 9 at the time of assembling the hydraulic excavator, first, before disposing the upper boom boss 19 between the lower boom brackets 18, The upper and lower mounting plates 23 are fastened using the respective mounting bolts 25. Then, the upper and lower mounting plates 20 are attached to these mounting plates 23.
And the projection 24 of the mounting plate 23 is held in a state of being fitted into the fitting recess 21 of the mounting plate 20.

Next, in this state, the lower boom 7 and the upper boom 9 are brought closer to each other, whereby the upper boom boss 1 is moved.
9 together with the mounting plates 20 and 23
8 at a predetermined position. And each mounting bolt 22
Is screwed into each screw hole 20B of the mounting plate 20 via each bolt insertion hole of the lower boom bracket 18, thereby fixing the mounting plate 20 to the lower boom bracket 18.

Thus, in this embodiment, the mounting plate 2 provided on each lower boom bracket 18 with the projection 24 of each mounting plate 23 provided on the upper and lower surfaces of the upper boom boss 19 is provided.
The bearing device 1 is slidably fitted into the fitting recess 21 of the bearing device 1.
7, the lower boom 7 and the upper boom 9 can be rotatably connected to the lower and right booms 9 via the fitting concave portions 21 and the convex portions 24, and the upper boom 9 rotates left and right with respect to the lower boom 7. In some cases, the upper boom 9 and the lower boom 7 can be smoothly rotated relative to each other via the bearing device 17 by the convex portion 24 being rotationally displaced in the fitting concave portion 21.

Accordingly, the lower boom 7 and the upper boom 9 can be reliably connected without using a connecting pin or the like as in the prior art, and the size and weight of the bearing device 17 and the working device 6 can be reduced.

Further, the mounting plate 20 is detachably mounted on the lower boom bracket 18 by means of the mounting bolts 22, and the mounting plate 23 is mounted by means of the mounting bolts 25 on the upper boom boss 1.
When the bearing device 17 is assembled, the mounting plate 20 is first mounted on the mounting plate 23 mounted on the upper boom boss 19, and the upper boom boss 19 is mounted together with the mounting plates 20 and 23 in this state. After being disposed between the lower boom brackets 18, the mounting plate 20 can be mounted on the lower boom bracket 18, and the bearing device 17 is provided.
Can be efficiently performed.

Further, since the mounting plates 20 and 23 are made of a self-lubricating metal material or a high-strength metal material having a sliding surface made of a self-lubricating material such as polytetrafluoroethylene, the lower boom bracket is used. When the upper boom boss 18 and the upper boom boss 19 rotate relatively, the mounting plate 2
0, 23 can be slid smoothly. This makes it possible to use the bearing device 17 without lubrication for a long period of time, thereby improving the maintainability.

Further, since the upper boom 9 and the arm stay 11 are connected to the left and right by a bearing device 26 having substantially the same configuration as the bearing device 17, the working device 6
Can be made smaller and lighter, and the assembling work of the working device 6 can be performed efficiently.

Next, FIG. 5 shows a second embodiment according to the present invention. In this embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be given. It shall be omitted. However, the bearing device 3 according to the present embodiment
The first feature is that a shim plate 32 for gap adjustment is arranged between the lower boom bracket 18 and the mounting plate 20 with respect to the bearing device 17 according to the first embodiment.

Thus, also in the present embodiment having such a configuration, it is possible to obtain substantially the same operation and effect as in the first embodiment. And especially in this embodiment,
The gap dimension formed between the mounting plate 20 on the lower boom bracket 18 and the mounting plate 23 on the upper boom boss 19 can be easily adjusted by the thickness of the shim plate 32. By simply replacing the plate 32 with another shim plate or the like having a different thickness dimension, the operation of adjusting the gap size can be performed efficiently.

In each of the above embodiments, the bearing device 1
7 is provided on the lower boom bracket 18 side, and the convex portion 24 is provided on the upper boom boss 19 side. However, the present invention is not limited to this, and the fitting concave portion 21 is provided on the upper boom boss 19. The projection 24 may be provided on the lower boom bracket 18.

In each of the above embodiments, the bearing device 1
The lower boom 7 of the hydraulic excavator and the upper boom 9 are connected to each other using the first and third hydraulic excavators 7 and 31, and the upper boom 9 and the arm stay 11 are connected to each other using the bearing device 26. Not limited to, for example, upper revolving superstructure 2
Bearings 17, 26, 31 such as a bearing provided between the arm and the lower boom 7, a bearing provided between the arm stay 11 and the arm 13, or a bearing provided between the arm 13 and the bucket 15. The bearing devices 17 and 31 may be used for bearings provided in construction machines such as hydraulic cranes and wheel loaders, and for other industrial machines and agricultural machines.

[0050]

As described in detail above, according to the first aspect of the present invention, one of the bracket member and the boss member is provided with a pair of convex portions, and the other member is provided with the convex portions. Since a pair of fitting recesses that are rotatably fitted are provided, the bracket member and the boss member can be rotatably connected via the protrusions and the fitting recesses, and these are smoothly rotated relative to each other. Can be done. Therefore, unlike the related art, it is not necessary to use a connecting pin or the like, and the bearing device can be reduced in size and weight, and the assembling operation can be performed efficiently.

According to the second aspect of the present invention, one of the bracket member and the boss member is detachably provided with a mounting plate having a convex portion, and the other member has a fitting concave portion in the other member. Since the mounting plate is provided detachably, when assembling the bearing device, the mounting plate of the bracket member is mounted on the mounting plate of the boss member, and these can be disposed between the bracket members together with the boss member, The assembling work of the bearing device can be performed efficiently.

According to the third aspect of the present invention, at least one of the mounting plates is made of a material having self-lubricating properties. The convex portion and the fitting concave portion of the mounting plate can be smoothly slid. This makes it possible to use the bearing device for a long period of time without lubrication, thereby improving its maintenance.

According to the fourth aspect of the present invention, since the shim plate is provided between the bracket member or the boss member and the mounting plate, the shim plate is provided between the bracket member mounting plate and the boss member mounting plate. The gap size to be formed can be easily adjusted by the thickness dimension of the shim plate.During maintenance of the bearing device, for example, the gap size adjustment operation can be performed simply by replacing the shim plate with another shim plate having a different thickness dimension. It can be performed efficiently.

Further, according to the invention of claim 5, since the bearing device is applied to the bearings provided on the lower boom, the upper boom and the arm stay of the working device, the working device can be made smaller and lighter. The workability when assembling the working device of the construction machine can be improved.

[Brief description of the drawings]

FIG. 1 is a front view showing a hydraulic shovel to which a bearing device according to a first embodiment of the present invention is applied.

FIG. 2 is a plan view of the working device showing a state in which the upper boom in FIG. 1 is rotated left and right on the distal end side of the lower boom.

FIG. 3 is a longitudinal sectional view of the bearing device as viewed from a direction indicated by arrows III-III in FIG. 2;

FIG. 4 is a cross-sectional view of the bearing device as viewed from a direction indicated by arrows IV-IV in FIG. 3;

FIG. 5 is a longitudinal sectional view showing the bearing device according to the second embodiment, viewed from the same position as in FIG. 3;

[Explanation of symbols]

 Reference Signs List 6 Working device 7 Lower boom 9 Upper boom 11 Arm stay 13 Arm 17, 26, 31 Bearing device 18 Lower boom bracket (bracket member) 19 Upper boom boss (boss member) 20, 23 Mounting plate 21 Fitting recess 24 Convex portion 32 Shim plate

Claims (5)

[Claims] 1. A bearing device in which a boss member is rotatably connected between a pair of bracket members, wherein one of the bracket member and the boss member has a pair of projections serving as a rotation axis. A bearing device, wherein the other member is provided with a pair of fitting concave portions into which the convex portions are rotatably fitted. 2. A structure in which the one member has a detachable mounting plate having the convex portion, and the other member has another mounting plate having the fitting concave portion detachably provided. 2. The bearing device according to 1. 3. The bearing device according to claim 2, wherein at least one of the mounting plate having the convex portion and the mounting plate having the fitting concave portion is formed of a self-lubricating material. 4. The bearing device according to claim 2, wherein a shim plate is provided on the bracket member or the boss member between the bracket member and the boss member. 5. A lower boom, an upper boom rotatably provided on the lower boom via a bearing, an arm stay rotatably provided on the upper boom via a bearing, and an upper and lower movement on the arm stay. The bearing device according to claim 1, 2, 3, or 4, wherein the bearing device is applied to a working device of a construction machine including an arm provided in the vehicle.