JP2556437Y2 - Bucket removal device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a device for attaching and detaching a bucket for a hydraulic shovel.

[0002]

2. Description of the Related Art FIG. 6 is a side view of a hydraulic excavator.
In the drawing, reference numeral 1 denotes a work attachment mounted on a front part of a hydraulic shovel, and 2 denotes a work attachment 1.
, 3 is an arm, 4 is a bucket, 5 is a bucket link, 6 is an idler link, 7 is a bracket erected on the back of the bucket 4, and 8 and 9 are connecting pins. FIG. 7 is a sectional view taken along line AA in FIG. In the drawing, 10 is an arm tip boss of the arm 3, 11 is a bucket link tip boss of the bucket link 5, 12 is an arm tip mounting pin hole drilled in the bracket 7, and 13 is a bucket link tip mounting pin. The holes 14 and 15 are locking portions when the pins 8 and 9 are pivoted.

As shown in FIGS. 6 and 7, in a conventional bucket attaching / detaching apparatus, a bracket 7 is erected on the back of a bucket 4, and a pin hole 12 for attaching an arm tip and a bucket link tip are attached to the bracket 7. The tool pin holes 13 are drilled 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 detached via pins 8 and 9.

[0004]

[Problems to be Solved by the Invention] In a hydraulic excavator, a bucket is frequently replaced in accordance with the type of work, the contents of work, or the state of work. In the prior art shown in FIGS. 6 and 7, since the pins are pivotally attached to the respective ends of the arm and the bucket link and the bracket of the bucket,
A driver or an operator pulls out the pin and replaces the bucket. The work of replacing the bucket requires a great deal of labor and time, and the work efficiency is reduced. For this reason, various types of bucket attachment / detachment devices that can easily and quickly replace the bucket have been considered. An object of the present invention is to provide a bucket attaching / detaching device that can solve the above-mentioned problems.

[0005]

According to the present invention, a bucket attaching / detaching device is separated into left and right sides inside the respective bosses with respect to an arm tip boss and a bucket link tip boss, and in the boss hole center direction within the boss. A movable piston pin is provided, and a spring is interposed between the left and right piston pins to urge the respective piston pins outward, and the left and right piston pins are pressed inward against the spring force of the spring by hydraulic operation. A bucket detachable device which is configured to be capable of being retracted and to be detachable between the arm tip and the bucket link tip and the bucket via the piston pin.
A pair of vertical plates are formed upright on the back surface of the bucket, and two sets of parallel pin holes of a bracket for connecting the tip of the arm and the tip of the bucket link are provided on the inner end surface of the vertical plate. In addition, a tapered portion for guiding the front end of the piston pin is formed so that the diameter of the opening hole on the inner end face is larger than the diameter of the pin hole, and becomes thinner in the outward direction to match the diameter of the pin hole.

[0006]

FIG. 1 is a sectional view of a bucket attachment / detachment device according to the present invention and a hydraulic circuit for operating the bucket attachment / detachment device. In the drawing, reference numeral 16 denotes a bracket fixed to the back of a bucket 4 '(an entire view of the bucket 4' is not shown), 17L and 17R denote a pair of right and left vertical plates of the bracket 16, and 18a and 18b denote brackets. Reference numeral 16 is a pin hole for attaching the tip of the arm, 19a and 19b are pin holes for attaching the tip of the bucket link, 20 is a boss at the tip of the arm,
21 is a bucket link tip boss, 22 is a piston pin fitted into each of the left and right ends of the arm tip boss 20 and the bucket link tip boss 21, 23 is a bush, 24 and 25 are seal members, 26 is Spring chambers inside the bosses 20 and 21, 27 are springs, 28 is a piston pin oil chamber, 29L, 29R, 30L and 30R are hydraulic ports communicating with the piston pin oil chamber 28, and 31 and 32 are the above. Spring chamber 26 of both bosses 20 and 21
An air passage opening the air inside to the outside, 33 is a frame,
34L and 34R are left and right plates of the frame 33, 35 is a central connecting plate, 36 is an electromagnetic switching valve, 37 is a hydraulic source provided in a hydraulic shovel, 38 is an oil tank, 39 is a power supply,
Reference numeral 0 denotes a switch arranged in a cab (not shown). Since the bucket 4 'is used by being inverted and replaced for backhoe excavation work and loading work, the inner diameters of the pin holes 18a-18b for mounting the arm tip and the pin holes 19a-19b for mounting the bucket link tip are the same size φd.
Is set to In addition, since the gap adjusting device 41 is provided to eliminate the rattling gap between the inner end face of the bracket 16 and the outer end face of the frame 33, the side of the bracket 16 on which the vertical plate 17L is attached to the arm tip. Pin hole 18
a is formed in a pin hole of the bush 42 with a collar. FIG. 2 is an enlarged view of the vicinity of the arm tip boss 20 in FIG.

FIG. 3 is a plan view of the bucket attaching / detaching device of the present invention. In the figure, reference numerals 43L and 43R denote positioning guide plates fixed to the outer surfaces of the left and right plates 34L and 34R of the frame 33, respectively. FIG. 4 is a side view of the bucket attaching / detaching device of the present invention as viewed from B of FIG. In the figure, an imaginary line A indicates a portion near the bracket 16 of the bucket 4 '.

Next, the structure of the bucket attaching / detaching apparatus of the present invention will be described with reference to FIGS. The bucket attaching / detaching device according to the present invention comprises a piston pin which is separated into left and right inside the respective bosses 20 and 21 with respect to the arm tip boss 20 and the bucket link tip boss 21, and is movable in the boss hole center direction in the boss. 22 and a spring 27 is interposed between the left and right piston pins 22, 22, and the piston pins 22,
22 are urged outwardly, and the switch 40 is turned on to switch the electromagnetic switching valve 36 to the open oil passage position B, so that the left and right piston pins 22, 22 are moved inward against the spring force of the spring 27. To be able to move in,
A bucket attachment / detachment device for attaching / detaching an arm tip and a bucket link tip and a bucket 4 'via the piston pin 22. A pair of upright plates 17L and 17R are erected on the back surface of the bucket 4'. And two sets of parallel pin holes (18a-18b), (19) of the bracket 16 connecting the tip of the arm and the tip of the bucket link.
a-19b), the pin holes 18a, 18
b, 19a, 19b, on the inner end face of the vertical plates (17L, 17R), the opening hole diameter on the inner end face (the opening hole diameter is φD as shown in FIG. 2) is larger than the pin hole diameter φd. And a tapered portion 44 for guiding the tip of the piston pin (22) so as to become thinner in the outward direction to match the pin hole diameter φd.
(Shown in FIG. 2).

Next, the operation of the bucket attaching / detaching device of the present invention will be described. Since the bucket 4 'is sometimes used by being inverted and replaced with respect to the tip of the work attachment, the structure and the assembly dimensions of the arm tip boss 20 and the bucket link tip boss 21 are set to be the same. When attaching the detached bucket 4 'to the tip of the work attachment, the switch 40 (shown in FIG. 1) is turned on before the attachment. The electromagnetic switching valve 36 is energized and switches to the opening oil passage position b. Since the pressure oil from the hydraulic pressure source 37 is supplied to the piston pin oil chambers 28 of both the bosses 20 and 21 via the position B of the electromagnetic switching valve 36, the piston pin 22 resists the spring force of the spring 27. , Plates 34L, 34R are retracted inward from the outer surfaces. Then, the driver operates the work attachment of the hydraulic excavator to insert the frame 33 inside the bracket 16 of the bucket 4 ′. The guide surfaces 45 of the positioning guide plates 43L and 43R fixed to the left and right of the frame 33 are respectively provided with boss portions 46a, 46b, 47a and 47b inside the vertical plates 17L and 17R of the bracket 16 for the bucket 4 '.
(Shown in FIG. 1). When operated in this state, the piston pins 22 in both bosses 20 and 21 are
And both pin holes (18a-18) of the bracket 16
b), (19a-19b) The hole centers are preset so as to be concentric with each other, but the positioning guide plates 43L and 43R are connected to the boss portions (46a, 46b,
47a, 47b), they are not exactly concentric due to a positioning error when they are brought into contact with each other. However, in the present invention, the diameter of the opening holes of the pin holes (18a, 18b, 19a, 19b) on the inner end faces of the vertical plates 17L, 17R of the bracket 16 is formed to be φD larger than the pin hole diameter φd. The pin diameter of the piston pin 22 is slightly smaller than the pin hole diameter φd, but is substantially φd, and the outer peripheral corner is chamfered on the tip end surface. Therefore, even if the above positioning error occurs, the distal end surface of the piston pin 22 can be positioned so as to face the opening hole diameter φD of the tapered portion 44.

As described above, the pin holes 18a, 18b, 19
The switch 40 is turned off when the distal end surface of each piston pin 22 is located within the range of the opening hole diameter φD of each of the tapered portions 44a and 19b. FIG. 5 is a diagram showing a state when the switch 40 is turned off in the bucket attaching / detaching device in FIG. The electromagnetic switching valve 36 is de-energized, and switches from the position B to the tank communication oil passage position C. Since the pressure oil from the hydraulic pressure source 37 does not act on the piston pin 22, the piston pin 22 is pushed outward by the spring force of the spring 27. At this time, the piston pins 22 are fitted into the pin holes 18a, 18b, 19a, and 19b, respectively, while the chamfered corners at the tip of the piston pins 22 are guided along the tapered portions 44. Thereby, even if the above-mentioned positioning error occurs, the bucket 4 'can be attached to the tip of the work attachment without any trouble. The operation for removing the attached bucket 4 'may be performed in a manner reverse to that of the above-described case of attachment.

[0011]

In the bucket attaching / detaching device of the present invention, a pair of vertical plates are formed upright on the back surface of the bucket, and the two sets of parallel pin holes of the bracket for connecting the tip of the arm and the tip of the bucket link are provided. On the other hand, on the inner end face of the vertical plate of the pin hole, the diameter of the opening hole on the inner end face is larger than the diameter of the pin hole, and it becomes thinner in the outer direction to guide the tip of the piston pin so that it matches the pin hole diameter. Was formed. Equipped with the bucket attachment / detachment device of the present invention, when attaching the detached bucket to the tip of the work attachment, with the piston pin retracted inside from the outer surface of the frame, place the frame inside the bucket bracket. Insert into. Then, the positioning guide plates fixed to the left and right of the frame are brought into contact with the boss inside the bracket of the bucket. When this positioning operation is performed, there is a positioning error. Therefore, the respective axes of the arm tip boss and the bucket link tip boss are exactly concentric with the two sets of parallel pin holes of the bucket bracket. It does not become. However, since the diameter of the opening of the pin hole on the inner end face of the vertical plate of the bracket is formed to be φD larger than the diameter of the pin hole φd, the piston pin is tapered within the range of the diameter of the opening hole φD. Can be positioned relative to the part. Then, in this state, when the piston pin is pushed out by a spring force, each piston pin is fitted into the pin hole while the chamfered corner at the tip of the piston pin is guided along the tapered portion. Therefore, in the bucket attaching / detaching apparatus of the present invention, even if a positioning error occurs during the bucket attaching operation, the bucket can be easily attached in a short time without any trouble.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a cross section of a bucket attaching / detaching device of the present invention and an operation circuit.

FIG. 2 is an enlarged view of the vicinity of an arm tip boss in FIG. 1;

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

FIG. 4 is a view as viewed from B in FIG. 3;

FIG. 5 is a diagram showing a state when a switch in FIG. 1 is turned off.

FIG. 6 is a side view of the excavator.

FIG. 7 is a cross-sectional view showing the conventional technique as viewed from AA in FIG. 6;

[Explanation of symbols]

 3 Arm 4, 4 'Bucket 5 Bucket link 7, 16 Bracket 10, 20 Arm tip boss 11, 21, Bucket link tip boss 12, 13, 18a, 18b, 19a, 19b Pin hole 17L, 17R Vertical plate 22 Piston Pin 27 Spring 33 Frame 36 Electromagnetic switching valve 43L, 43R Positioning guide plate 44 Taper

Claims (1)

(57) [Scope of request for utility model registration] An arm extremity boss and a bucket link extremity boss in a work attachment of a hydraulic shovel are provided with piston pins which are separated into left and right inside the respective bosses and which can move in the boss hole center direction in the bosses.
A spring is interposed between the left and right piston pins to bias the piston pins outward, and the left and right piston pins can be retracted and moved inward by hydraulic operation against the spring force of the spring. A bucket attaching / detaching device configured to attach / detach a tip and a bucket link tip and a bucket via the piston pin, wherein the bucket attaching / detaching device is formed by erecting a pair of vertical plates on the back surface of the bucket, For the two parallel pin holes of the bracket connecting the bucket link tip, the opening hole diameter at the inner end surface is larger than the pin hole diameter at the inner end surface of the vertical plate, A bucket attaching / detaching device characterized in that a tapered portion for guiding a piston pin tip portion is formed so as to be thinned to match a pin hole diameter.