JPH0354196Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an improvement of a telescopic arm in which a slide arm is slidably engaged with a base arm which is pivoted to a boom etc. of the main body of an earth-moving machine. This invention relates to a telescopic arm in which the arm slides in surface engagement and the front sliding engagement part that is affected by earth and sand is formed inside the side surface of the slide arm.

[Prior art]

As a telescopic arm for expanding and expanding the range of work by making the arm of earth-moving machines such as excavators telescopic, guide plates are installed at both ends of the bottom of the base arm connected to the tip of the boom and the top of the slide arm. A device is known in which an upper and lower roller attached to the tip of an arm and an upper and lower roller attached to the rear end of a slide arm are engaged with each other so as to sandwich a mating guide plate.

However, in this structure, the load during excavation is received at the point of the roller pin, so the load is concentrated on the pin, and there is a strength problem in that it is easily deformed and broken.

In addition, this type of equipment has a structure in which the rollers roll on the guide rail exposed to the outside to expand and contract, so dirt and concrete lumps attached to the rail surface are bitten by the rollers, which can also cause deformation of the roller shaft.
It tends to break, and the axis of the entire arm tends to twist, preventing smooth expansion and contraction. In particular, since the rail of the front slide arm protrudes outward, it is not only easily deformed by external obstacles, but even if local deformation occurs, the roller rolls on the deformed surface at the point of contact. This adversely affects other members, such as roller wear and uneven wear, making maintenance extremely difficult.

[Purpose of invention]

The first object of the present invention is to provide a telescopic arm that can withstand large excavation loads by eliminating deformation and damage of the engaging members of the base arm and slide arm.

Another purpose of the present invention is to protect the slide engagement surfaces of the base arm and slide arm from dirt and sand, thereby ensuring smooth expansion and contraction. The purpose is to make maintenance easier.

[Summary of the idea]

The slide arm is slidably engaged with a base arm that is pivotally attached to the tip of a boom, etc., and the slide arm is telescopically slid along the base arm using a driving means such as a hydraulic cylinder installed between both arms. The feature of this invention is that the telescopic arm of the earth-moving machine has rails extending in the axial direction protruding outward on both the left and right sides of the base arm.
Guide grooves with a U-shaped cross section are formed that are recessed inward in the axial direction on both the left and right sides of the slide arm, and grooves and grooves are slidably engaged in the guide grooves of the slide arm on both left and right sides near the tip of the base arm. A bracket integrally formed with a hook-shaped slide block is attached, and a bracket is integrally formed near the rear of the slide arm with a slide block having a U-shaped cross section that slidably engages with the rail of the base arm. As a result, the U-shaped guide groove of the slide arm and the hook-shaped block of the base arm are surface-engaged on the inside of the side surface of the slide arm, and the rail of the base arm and the U-shaped slide block of the slide arm are connected to each other. This is due to the fact that they are surface engaged. Preferably, a shim is removably attached to the sliding surface of each slide block, and wipers may be fixed to both ends of the slide block to protect the block.

[Example of idea]

An embodiment of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 1, the telescopic arm 1 includes a base arm 1a connected to the tip of the boom 2 of the main body of the earth-moving machine, and a slide slidably engaged above the base arm along the axial direction of the base arm 1a. Arm 1b, base arm 1a and slide arm 1b
It is constructed from driving means such as a hydraulic cylinder 3, which is installed between the two base arms and moves the slide arm 1b back and forth along the base arm 1a.

A series of outwardly projecting guide rails 4 are provided on the upper edges of both the left and right sides of the base arm 1a and extend from the rear to the front, and the other slide arm 1
Attachment mounting holes 5 on the left and right sides of b
A series of inwardly recessed guide grooves 6 are formed parallel to the lower surface of the arm 1b from the vicinity of the arms 1b to the rear. It is preferable for the guide groove 6 to have a U-shaped cross section as shown in FIG. 2 in terms of strength.

These guide rails 4 and guide grooves 6 are provided at appropriate lengths and positions depending on the desired extension and contraction stroke of the telescopic arm 1.

As shown in FIG. 2, upwardly extending brackets 7, 7 are removably fixed on the left and right sides of the front part of the base arm 1a, preferably with four bolts 8, etc. A slide block 9 that is engaged with the guide groove 6 of the slide arm 1b is integrally provided so as to project inward in a hook shape.

On the other hand, as shown in FIG.
Brackets 1 extending downward on both left and right sides of the rear part of b.
0 and 10 are preferably removably fixed with four bolts 11, etc., and each of these brackets 1
A slide block 12 having a U-shaped cross section and having a lateral groove 12' for slidably engaging the guide rail 4 of the base arm 1a in a concave and convex manner is integrally connected to the inside of the base arm 1a.

In addition, 13 in the figure is a grease oil inlet provided in the slide blocks 9 and 12, and is designed to supply lubricating grease to the sliding surfaces through grease holes (not shown) formed in the wall thickness of the blocks. It's getting old.

In this way, the slide arm 1b engages the slide block 9 at the front of the base arm 1a in a concave-convex manner in the guide groove 6 formed on the inside of the side surface, and also engages the U-shaped slide block 12 provided at the rear of the slide arm 1b. The guide rail 4 of the base arm 1b is fitted into the lateral groove 12' of the base arm 1b so as to be slidable.

One end of a driving means such as a hydraulic cylinder 3 is pivotally connected to a bracket 14 provided at the rear upper part of the base arm 1b.The hydraulic cylinder 3 is disposed through the inside of the slide arm 1b, and the other end is connected to the slide arm 1b. Pin 1 installed between the side plates of
It is pivoted to 5.

In addition, 16 in the figure is a working attachment connected to the tip mounting holes 5a and 5b of the slide arm 1b.
7 is a link, and 18 is a working hydraulic cylinder installed between the upper bracket 19 of the slide arm 1b and the attachment operating link 17.

In order to smooth the sliding motion between the base arm 1a and the slide arm 1b, and to facilitate the wear and maintenance of the sliding surfaces of the slide blocks 9 and 12, a more preferable embodiment is as shown in FIGS. 2 and 3. Then, a shim 20 is attached to the sliding surface of each slide block 9, 12 with the mating member.

That is, as shown in FIG. 2, the slide arm 1 is attached to the slide block 9 of the base arm 1a.
A shim 20 is removably attached to the contact surface with the U-shaped guide groove 6 of b with a bolt 21. This shim 20 projects slightly inward from the tip of the slide block 9, and the common shim 20 protects not only the upper or lower sliding surface of the block 9 but also the inner side surface at the same time.

Similarly, as shown in FIG. 3, shims are also provided on the upper surface and inner side surface of the slide block 13, which has a U-shaped cross section and is attached to the slide arm 1b, that is, on the contact surface of the base arm 1a with the guide rail 4. 20 is detachably attached via bolts 21 or the like.

These shims 20 are preferably made of a material with a small coefficient of friction, such as hard plastic (hard nylon).

As shown in FIGS. 4 and 5, earth and sand on the sliding surfaces of the guide groove 6 and guide rail 4 on the other side that are in sliding contact with each other are removed from the front and rear ends of each slide block 9, 13, and A wiper 22 for protecting the shims 20 and 9, 12 is removably fixed with bolts 23. These wipers 22 are usually made of a flexible material such as rubber.

The telescopic arm of the present invention usually has a bracket 23 provided at the rear lower part of the base arm 1a.
The pin hole 24 is pivotally attached to the tip of the boom 2 of the earth-moving machine main body, and one side of the arm rotation cylinder 26 is connected to the pin hole 25 at the rear end of the base arm 1b. By adjusting the extension and contraction of the arm 1b along the base arm 1a, the working position of the working attachment 16 can be freely selected and used within the range of the extension and contraction stroke of the telescopic arm 1.

[Effect of idea]

In the telescopic arm of the present invention, the base arm and the slide arm are in abutting engagement with each other on a flat surface, so the surface pressure per unit is small, so it can withstand a large load, and it also has a guide groove when sliding. Since the dirt and the like on the guide rail surface are removed, there is no risk of dirt and the like getting mixed into the sliding surface.

In particular, since the engagement portion between the slide block of the base arm and the slide arm is located inside the side surface of the arm, there is no risk of dirt or sand getting mixed in or damaging the sliding contact surface even if dirt or the like falls on the front of the arm during work.

In addition, if shims are removably attached to the sliding surface of the slide block, only the shim needs to be replaced when it wears out, and the slide block itself can be used as is, making it significantly more economical than replacing the entire roller. be.

Furthermore, if the slide block is provided with a wiper, dirt on the guide groove or guide rail surface can be removed in advance, thereby protecting the slide block (particularly the shim) and extending its life.

[Brief explanation of the drawing]

Fig. 1 is a side view of the telescopic arm of the present invention, Fig. 2 is a sectional view taken along the - line in Fig. 1, Fig. 3 is a sectional view taken along the - line in Fig. 1, and Fig. 4 is the portion shown in Fig. 2. Side view, FIG. 5 is a partial side view of FIG. 3. 1a...Base arm, 1b...Slide arm, 3...Hydraulic cylinder, 4...Guide rail,
6... Guide groove, 7, 10... Bracket, 9, 1
2...slide block, 20...shim, 22...
...wiper.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A slide arm is slidably engaged with a base arm pivotally attached to the tip of a boom, etc., and the slide arm is moved along the base arm using a hydraulic cylinder installed between both arms. In a telescopic arm of an earth-moving machine that is extendable and retractable, guide rails 4 extending in the axial direction are provided on both left and right sides of a base arm 1a to protrude outward, and guide rails 4 are recessed inward in the axial direction on both left and right sides of a slide arm 1b. A guide groove 6 having a U-shaped cross section is formed, and a hook-shaped slide block 9 is provided on both left and right sides near the tip of the base arm 1a so as to be slidably engaged with the guide groove 6 of the slide arm 1b. On the other hand, a slide block 12 having a U-shaped cross section is attached near the rear of the slide arm 1b to slidably engage with the guide rail 4 of the base arm 1a.
A telescopic arm for an earth-moving machine, characterized in that a bracket 10 integrally formed with the bracket 10 is attached. (2) The telescopic arm according to claim 1, wherein a shim 20 is detachably attached to each sliding contact portion of the slide block 9 of the base arm 1 and the slide block 12 of the slide arm 1b. (3) The telescopic lens according to claim 1 or 2, wherein the slide block 9 of the base arm 1a and the slide block 12 of the slide arm 1b have wipers 22 at both their front and rear ends. arm.