JPH0657952U - Structure of bucket desorption device - Google Patents

Abstract

(57) [Summary] [Purpose] For hydraulic excavators, the buckets are often replaced depending on the work situation. 2. Description of the Related Art Conventionally, various bucket attachment / detachment devices that allow a driver to replace a bucket by operating in a driver's cab have been considered. The invention is
A structure of a bucket attaching / detaching device is provided. [Structure] In the structure of the bucket attaching / detaching device of the present invention, the pin portion of the piston pin provided at each end of the arm tip boss and the bucket link tip boss and the sliding movement of the opposite bosses on which the piston portion slides The portion is provided with a seizure-resistant pin portion bush and a piston portion bush, respectively.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a desorption device for a hydraulic excavator bucket.

[0002]

[Prior art]

 FIG. 6 is a side view of the hydraulic excavator. In the figure, 1 is a work attachment mounted on the front portion of a hydraulic excavator, 2 is a boom of the work attachment 1, 3 is an arm, 4 is a bucket, 5 is a bucket link, 6 is an idler link, 7 is a bucket 4 Brackets, which are erected on the rear surface of, and 8 and 9 are connecting pins. FIG. 7 is a sectional view taken along the line AA of FIG. In the figure, 10 is the arm tip boss of the arm 3, 11 is the bucket link tip boss of the bucket link 5, 12 is the arm tip mounting pin hole opened in the bracket 7, and 13 is the bucket link tip mounting. The pin holes 14 and 15 are locking portions when the pins 8 and 9 are pivotally attached.

As shown in FIG. 6 and FIG. 7, in the bucket attaching / detaching device of the prior art, a bracket 7 is erected on the back surface of the bucket 4, and the bracket 7 has an arm tip attaching pin hole 12 and a bucket link tip. The mounting pin holes 13 are opened in parallel with each other so that the tip of the arm 3 and the tip of the bucket link 5 of the work attachment 1 and the bracket 7 of the bucket 4 are attached and detached via the pins 8 and 9. ing.

[0004]

[Problems to be solved by the device]

 For hydraulic excavators, the buckets are often replaced depending on the type of work, work content or work status. In the prior art shown in FIG. 6 and FIG. 7, pins are pivotally attached to the tip ends of the arm and bucket link and the bracket of the bucket, respectively. Therefore, the driver or the operator pulls out the pins and replaces the bucket. Was being done. Therefore, it takes a lot of labor and time to replace the bucket, and the work efficiency is lowered. For this reason, conventionally, various consideration has been given to a bucket attaching / detaching device (not shown) in which the driver can change the bucket by operating the driver in the cab. An object of the present invention is to provide a structure of the bucket attaching / detaching device.

[0005]

[Means for Solving the Problems]

 In the bucket attaching / detaching device of the present invention, a bracket is provided upright on the back surface of the bucket, and an arm tip attaching pin hole and a bucket link tip attaching pin hole are opened in the bracket in parallel with each other. A piston pin is provided inside each of the bosses for the arm tip boss and the bucket link tip boss, and the piston pin is separated left and right and can move in the axial direction of the boss. Also, in the bucket attaching / detaching device for attaching / detaching the bucket link tip portion to the bucket bracket, the diameter of the pin portion of the piston pin is equal to the diameter of the pin hole formed in the bracket of the bucket. Size, and the diameter of the piston part of the piston pin is set to be larger than that of the pin part. The pin portion bushing and the piston portion Bush having seizure resistance which is configured by providing each of the sliding portion of the.

[0006]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a view showing a cross section of a bucket attaching / detaching device of the present invention and a hydraulic circuit for operating the bucket attaching / detaching device. In the figure, the same reference numerals are given to those using the same constituent elements as those in the prior art. 16 is a boss portion for the arm tip mounting pin hole 12 fixed to the inner surface side of the bracket 7 of the bucket 4 which is opposed to the boss portion 17, and 17 is a boss portion for the bucket link tip mounting pin hole 13. Reference numeral 18 is an arm tip boss, 19 is a bucket link tip boss, 20 is a piston pin fitted to both left and right ends of the arm tip boss 18 and the bucket link tip boss 19, and 21 is a piston pin 20. Pin portion, 22 is a piston portion, 23 is a pin portion bush, 24 is a piston portion bush, 25, 26 and 27 are sealing members, respectively, 28 is a space between the left and right pistons 20 and 20 in both the bosses 18 and 19. The springs 29 are fitted in the spring chambers, 29 is a spring chamber, 30 is an oil chamber for piston pins, and 31L and 31R are bored in the boss 18 at the tip of the arm so that the oil chambers 30, 30 for the left and right piston pins are opened. Hydraulic ports communicating with each other, 32L and 32R are opened to the bucket link tip boss 19 and communicate with the left and right piston pin oil chambers 30, 30, respectively, and 33 is both the bosses 18 and An air passage that opens the air in the spring chamber 29 of 19 to the outside, 34 is a frame, 35L and 35R are left and right plates of the frame 34, 36 is a central connecting plate, 37 is a switching valve, and 38 is hydraulic pressure. A hydraulic power source 39 for the shovel is an oil tank. Since the bucket 4 is used by exchanging and exchanging the excavation work and the loading work, the inner diameters of the arm tip end attachment pin hole 12 and the bucket link tip end attachment pin hole 13 are set to the same dimension φd. . Therefore, the diameter of the piston pin 20 is also the same size φd (to be precise, since the piston pin 20 must be inserted into each of the pin holes 12 and 13), the diameter of the piston pin 20 is slightly smaller than that of the pin holes 12 and 13. It has been set to a small diameter).

The bucket attaching / detaching device of the present invention is constructed symmetrically, and FIG. 2 is a detailed view of a portion B of FIG. In the figure, reference numeral 40 denotes a greasing port for injecting grease for lubrication into a sliding portion between the inner peripheral surface of the pin portion bush 23 and the outer peripheral surface of the pin portion (21) of the piston pin 20. FIG. 3 is a plan view of the bucket attaching / detaching device of the present invention. In the figure, 41L and 41R are positioning guide plates fixed to the outer side surfaces of the left and right plates 35L and 35R of the frame 34, respectively. FIG. 4 is a side view of the bucket attaching / detaching device of the present invention viewed from C of FIG. In the figure, reference numeral 42 is a guide surface of the positioning guide plate 41L (41R).

Before describing the structure of the bucket attaching / detaching device of the present invention, the operation of the bucket attaching / detaching device will be described. First, when attaching the removed bucket 4 to the tip of the work attachment, the switching valve 37 shown in FIG. 1 is operated to the open oil passage position a. Since the pressure oil from the oil pressure source 38 is sent to the piston pin chambers 30 of both bosses 18 and 19 through the position of the switching valve 37, the piston pin 20 is pulled inward against the spring force of the spring 28. It is in a state. In this way, the tip of the piston pin 20 is retracted inward from both the left and right outer surfaces of the frame body 34, so that the driver operates the work attachment of the hydraulic excavator to move the bracket 7 of the bucket 4 to the opposite boss portion. The outer surface side of the frame 34 is inserted into the inner surface sides of 16 and 17, respectively. At the same time, the guide surfaces 42 of the positioning guide plates 41L and 41R fixedly provided on the left and right of the frame 34 come into contact with the upper outer peripheral surfaces of the boss portions 16 and 17 of the bucket 4 bracket 7. When operated in this state, the shaft centers of the piston pins 20 of both bosses 18 and 19 and the hole centers of both pin holes 12 and 13 of the bracket 7 of the bucket 4 are aligned, so the switching valve 37 is connected to the tank from the position a. Switch to oil passage position b. 5 is a diagram showing a state in which the switching valve 37 in FIG. 1 is operated to cause the piston pin 20 to project and move. As shown in FIG. 5, since the pressure oil from the hydraulic pressure source 38 does not act on the piston pin 20, the spring 28 extends due to the spring force, and the piston pin 20 is projected outward. Since the protruding tip side of the piston pin 20 is fitted into the pin holes 12 and 13 of the bucket 4, the bucket 4 can be attached to the tip of the work attachment. The operation for removing the attached bucket 4 may be performed in the reverse order of the above-mentioned attachment.

Next, the structure of the bucket attaching / detaching device of the present invention will be described with reference to FIGS. 1 and 2. According to the present proposal, the diameter φd of the pin portion 21 of the piston pin 20 provided at both left and right ends of the arm tip end boss 18 and the bucket link tip end boss 19 is defined by the diameter of the pin that is opened in the bracket 7 of the bucket 4. The diameter is set to be the same as the diameter of the holes (12, 13), and the diameter φD of the piston portion 22 of the piston pin 20 is set to be larger than that of the pin portion 21, so that the pin portion 21 and the piston portion 22 are A pin bush 23 and a piston bush 24 having seizure resistance are respectively provided on the sliding portions of the sliding bosses 18 and 19 on the opposite side. The pin portion bush 23 and the piston portion bush 23 may be integrally formed although not shown.

Next, the operation of the above structure in the bucket attaching / detaching device of the present invention will be described. In the present invention, the arm tip boss 18 and the bucket link tip 19 respectively function as cylinders. Since the pin portion 21 of the piston pin 20 is fitted into the pin hole of the pin portion bush 23, the pin portion 21 is supported by the pin hole and slides. Moreover, since lubricating grease is injected into the sliding portion from the greasing port 40, seizure will not occur. However, the spring chamber (29) side of the piston portion 22 of the piston pin 20 is open to the outside air (air). Therefore, the sliding portion of the outer peripheral surface of the piston portion (22) is likely to run out of oil, but in the present invention, the sliding portion of the bosses 18 and 19 is provided with a metal or non-metal piston portion bush 24 having resistance to seizure. Therefore, the seizure accident of the piston portion 22 can be prevented. Since the sliding surface of the piston pin 20 is hardened by heat treatment and the material of the bosses 18 and 19 is structural steel having a small seizure resistance, a so-called seizure bush is used for the piston bush 24. This prevents accidents such as seizure and galling.

[0011]

[Effect of device]

 According to the structure of the bucket attaching / detaching device of the present invention, the pin portion of the piston pin provided at the left and right end portions of the arm tip boss and the bucket link tip boss, and the sliding portion of the opposite boss on which the piston portion slides. , A pin bush and a piston bush having seizure resistance are provided respectively. Therefore, lubricating grease can be injected from the greasing port to the sliding surface between the pin portion of the piston pin and the pin hole of the pin bush, so seizure will not occur. And the piston part of metal or non-metal which has seizure resistance on the sliding part of the mating boss against the sliding part on the outer peripheral surface of the piston part which is open to the outside air and is in contact with the spring chamber side. Bush is provided. Therefore, the structure of the bucket attaching / detaching device of the present invention can prevent accidents such as seizure and galling even if oil runs out at the sliding portion on the outer peripheral surface of the piston during sliding.

[Brief description of drawings]

FIG. 1 is a view showing a cross section of a bucket attaching / detaching device of the present invention and a hydraulic circuit for its operation.

FIG. 2 is a detailed view of a B part in FIG.

FIG. 3 is a plan view of the bucket attaching / detaching device of the present invention.

FIG. 4 is a side view seen from C in FIG.

FIG. 5 is a diagram showing a state in which the piston pin in FIG. 1 is moved in a protruding manner.

FIG. 6 is a side view of the hydraulic excavator.

7 is a cross-sectional view showing the conventional technique seen from AA in FIG.

[Explanation of symbols]

 4 Bucket 7 Bracket 10,18 Arm tip boss 11,19 Bucket link tip boss 20 Piston pin 21 Pin portion 22 Piston portion 23 Pin portion bush 24 Piston portion bush 28 Spring 29 Spring chamber 30 Piston pin oil chamber 37 Switching valve

Claims (1)

[Scope of utility model registration request] 1. A bracket is erected on the back surface of the bucket,
On the bracket, a pin hole for attaching the arm tip portion and a pin hole for attaching the bucket link tip portion are opened in parallel with each other, while the arm tip boss and the bucket link tip boss are left and right inside the respective bosses. A bucket attaching / detaching device in which a piston pin that is separated and is movable in the axial direction of the boss is provided, and the tip of the arm and the tip of the bucket link are detached from the bracket of the bucket via the piston pin. Set the diameter of the pin portion of the piston pin to the same size as the diameter of the pin hole opened in the bucket bracket, and set the diameter of the piston portion of the piston pin to be larger than that of the pin portion. , A pin portion bush and a piston portion bush having seizure resistance are respectively provided on the sliding portions of the opposite bosses on which the pin portion and the piston portion slide. Bucket desorber, characterized in that provided.