JPH083186B2 - Bucket attachment / detachment mechanism for construction machinery - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction machine used for digging and leveling earth and sand, and in particular, a bucket for performing various civil works can be detachably connected to the tip of an arm. The present invention relates to a bucket attachment / detachment mechanism for a construction machine.

[0002]

2. Description of the Related Art Conventionally, in construction machines, especially excavators, machines used for digging holes and digging called backhoes, the bucket attached to the arm is often replaced for the purpose of the operation. It was This excavator was widely used in civil engineering and construction work.
In this excavator, a bucket for excavating earth and sand is connected to the tip of an arm. By swinging this arm and the bucket vertically with a hydraulic cylinder, it is possible to save labor and improve work efficiency in the work of digging earth and sand and forming a groove.

However, these days, the excavator is not used only for the purpose of simple drilling work, but it is often used for other work purposes by utilizing its mechanism. That is,
BACKGROUND ART Buckets attached to arms are connected to accessories for other work, and applications for specific civil work and construction work are becoming popular. For example, buckets with different excavation widths may be attached to work depending on the hardness of earth and sand and the width of grooves. In addition, a breaker may be connected to the tip of the arm, or a grip may be attached to the arm for breaking work or cargo handling work. By combining these various accessories with the arm, the excavator can be used for various construction work, and the applicability at the work site can be spread.

In the case of attaching and detaching the bucket to and from the tip of the arm, the conventional work of changing the attachment is complicated. First, the bucket attached to the end of the arm had to be removed and accessories for other uses had to be manually connected. In this manual work, the two connecting pins connecting the arm and the bucket must be removed and the bucket must be separated from the arm.
Then, after connecting other accessories to the arm, a connecting pin had to be inserted between the accessory and the arm.

A series of operations for attaching and detaching the bucket to and from the excavator have been performed manually. Moreover, a plurality of workers are required for the attachment / detachment work, resulting in a reduction in personnel efficiency at the work site. Further, it takes a lot of time to insert and remove the connecting pin and replace the bucket, and it is not possible to quickly deal with the problem by changing the most suitable accessory for the work site.

For this reason, the bucket can be quickly attached to and detached from the tip of the arm according to the purpose of use at the work site, and if the number of workers required for this attachment and detachment can be reduced, It was possible to improve the efficiency of the site of civil engineering and construction work.

[0007]

Therefore, if the bucket attached to the tip of the arm can be attached and detached only by the operator who operates the excavator and the bucket can be exchanged with the accessory for other uses, the replacement is required. Therefore, another worker is not needed, and the number of workers can be reduced. Furthermore, in connecting the arm and bucket, if the shaft holes are connected by pin connection, not by simply hooking them together, the mechanism can be deformed by sufficiently holding even if a large acting force is applied to the bucket and arm. There are few.

For this reason, the same inventor as the inventor of the present application has proposed a bucket attaching / detaching mechanism in which a pair of engaging claws which can be expanded and contracted vertically are provided at the tip of the arm in order to solve this problem. No. 196763 of the second year of the wish, 25th year of the special application
0697). Similarly, a structure is also proposed in which a claw is provided on the upper side of the tip of the arm, and a connecting pin that can be extended to the left and right is provided below the claw (Japanese Patent Application No. 2243203).
No. 243204 of Japanese Patent Application No. 2). Furthermore, a structure is proposed in which a horizontal groove is opened at the tip of the arm, the bucket is hooked by the claw located above the tip of the arm, and then the connecting rod fixed to the bucket is inserted into the groove and gripped. (Japanese Patent Application No. Hei 2 305558).

In these newly proposed constructions, the construction is extremely complicated, and since the connection between the arm and the bucket is engaged not by the pin connection but by the upward claw, a large acting force is applied to the bucket. The nails were deformed, and it was difficult to withstand long-term use. Further, between the arm and the bucket, both of them often rotate and move during the work. Therefore, it is preferable that both of them be connected by pin connection with a pin hole and a connecting pin.

As described above, it has been desired to develop a bucket attaching / detaching mechanism for a construction machine which facilitates the connection of the arm and the bucket, facilitates the positioning of the pin hole for inserting the connecting pin, and can connect the bucket and the arm with the pin. Further, if desired, in connecting the arm and the bucket by the connecting pin, it is preferable that the arm and the bucket are connected by pins at two front and rear positions. In this, the arm and the bucket are usually connected so as to form a link mechanism, and both are swingably connected so that the angle can be changed in the working mode. For this reason,
When an acting force is applied to the bucket, this stress concentrates on the connecting portion, and if the arm and bucket are connected by only one connecting pin, the member is easily deformed. Therefore, in the mechanism for connecting the arm and the bucket, it was preferable to connect the two at two or more places by pins.

Therefore, the bucket and the arm can be easily pinned at two or more places by facilitating the connection of the arm and the bucket with a simple mechanism and by accurately positioning the front and rear pin holes. It has been desired to develop a bucket attachment / detachment mechanism for construction machines that can be connected.

[0012]

According to the present invention, there is provided a movable vehicle body, a boom which is vertically swingably connected to the vehicle body, and an arm which is vertically swingably connected to a tip of the boom. In a construction machine including a bucket that is detachably engaged with the tip of this arm, a pair of engagement links whose lower ends are rotatably connected to the left and right of the tip of the arm, and the front side of each engagement link. With the engaging claws protruding upward, the base part of the engaging claws is connected to the rear of the arm, and the cylinder rods of the bucket cylinders are connected to the upper parts of both engaging links, and No. 1 pin hole, a second pin hole opened at the tip of the arm at a position coaxial with the rotation center of the engagement link, a pair of brackets fixed to the back surface of the bucket at a distance, and Provided between brackets The engaging pin, the third pin hole opened at a position close to the hook pin of each bracket, the fourth pin hole opened at a position distant from the hook pin of each bracket, and the engaging claws. It is formed by the first connecting pin that is commonly inserted into the first and third pin holes when the hooking pin is inserted into the engaging groove formed by the mating link, the engaging claw, and the engaging link. A bucket attachment / detachment mechanism for a construction machine, comprising a second connecting pin that is commonly inserted into the second and fourth pin holes when the hooking pin is inserted into the engagement groove. To do.

Further, in the present invention, the movable vehicle body, the boom vertically swingably connected to the vehicle body, the arm vertically swingably connected to the tip of the boom, and the tip of the arm. In a construction machine comprising a bucket removably engaged with a shaft, a cylindrical bearing rotatably inserted into the tip of the arm so that the axis line is perpendicular to the length direction, and the shaft core of the bearing. A second pin hole that penetrates through and is open to the left and right, a pair of engagement links that are located on the left and right sides of the arm and that connect the lower parts of the arms to both ends of the bearing, and project upward toward the front side of each of the engagement links. The engaging claw, the first pin hole opened in the upper part of each engaging link, the base part of which is connected to the rear of the arm, and the cylinder cylinder of which is connected to the upper part of both engaging links; It is the tip of the arm and Second pin hole opened at a position coaxial with the rotation center of the, a pair of brackets fixed to the back surface of the bucket at a distance, a hooking pin provided between both brackets, and a hooking pin of each bracket To the third pin hole opened at a position close to each other, a fourth pin hole opened at a position apart from the hooking pin of each bracket, and an engagement groove formed by the engaging claw and the engaging link. A state in which the hooking pin is inserted in the engaging groove formed by the first connecting pin and the engaging claw and the engaging link, which are commonly inserted into the first and third pin holes when the engaging pin is inserted. In this case, the bucket attaching / detaching mechanism of the construction machine is provided, which is composed of the second connecting pin that is commonly inserted into the second and fourth pin holes.

Further preferably, the distance between the first and second pin holes is set to be substantially the same as the distance between the third and fourth pin holes. The present invention provides a bucket attaching / detaching mechanism.

Preferably, the outer distance of the engaging links provided on the left and right of the arm is set to be substantially the same as the inner distance of the pair of brackets fixed to the bucket. The present invention provides a mechanism for attaching and detaching a bucket of the construction machine described above.

Preferably, the distance between the engaging groove formed by the engaging claw and the engaging link and the first pin hole is set to be substantially the same as the distance between the hooking pin fixed to the bracket and the third pin hole. Claims 1 and 2 characterized in that
The present invention provides a mechanism for attaching and detaching a bucket of the construction machine described above.

[0017]

According to the present invention, a pair of engaging links are connected to the left and right of the tip of the arm, and first and second pin holes are opened above and below each engaging link. Has an engaging claw facing upward, and an engaging groove is formed between the engaging link and the engaging claw. Further, third and fourth pin holes are opened in the bracket of the bucket, and a hooking pin is fixed between both brackets. Therefore, after swinging the arm to hook the hooking pin in the engaging groove to align the engaging link and the bucket, the first connecting pin is inserted into the first and third pin holes, The second connecting pin to the second
And the bucket and the engagement link can be connected by inserting into the fourth pin hole. In this connection, since the arm and the bucket are pin-connected by two connecting pins, the connection between the two becomes strong, and even if a large stress is applied to the bucket, there is no possibility of deformation at the connecting portion.

With such a procedure, the position of the pin hole of the engaging link and the pin hole of the bucket can be easily determined by hooking the hook pin in the engaging groove even if only one operator is present. Therefore, the bucket and various accessories can be attached to and detached from the tip of the arm, and the accessories suited to the purpose of use at the work site can be quickly replaced to improve work efficiency.

[0019]

An embodiment of the present invention will be described below with reference to the drawings. In this embodiment, FIG. 1 is a perspective view of the entire excavator showing a state in which a bucket attaching / detaching mechanism is provided at the tip of the arm, FIG. 2 is an enlarged view showing the tip of the arm of the excavator, and FIG. It is explanatory drawing which shows the shape of each member in an arm and a bucket, FIG. 4 is a top view which shows the length of each member in an arm and a bucket, and FIG. 5 is sectional drawing of the state which attached the bucket to the front-end | tip of an arm. FIG. 6 is a perspective view showing a state in which the bucket is hooked on the arm.

Crawlers 2 are provided on the lower left and right sides of the vehicle body 1 accommodating the engine and the like, and the crawler 2 allows the vehicle body 1 to freely move back and forth and left and right. A boom 3 bent in a slightly V shape is attached to the front of the vehicle body 1 so as to be vertically swingable.
Hydraulic cylinders 4 for raising and lowering are respectively interposed between the right and left of the center of the boom 3 and the front surface of the vehicle body 1, and the boom 3 is swung up and down by the hydraulic cylinders 4. .

An elongated arm 5 is vertically swingably connected to the upper end of the boom 3, and a swing hydraulic cylinder 6 is provided between the center of the rear surface of the boom 3 and the rear end of the arm 5. Is intervened. With this hydraulic cylinder 6, the arm 5 can be swung up and down with respect to the boom 3. A rear end of the bucket cylinder 7 is connected to the center of the rear surface of the arm 5, and a start-up link 9 is connected to the left and right ends of the cylinder rod 8 of the bucket cylinder 7. The lower ends of the rising links 9 are rotatably connected to both sides near the tip of the arm 5.

A pair of connecting links 10 are connected in parallel to the tip of the cylinder rod 8, and the tip of the connecting link 10 is directed toward the tip of the arm 5. A pair of engagement links 11 are arranged in parallel between the tip ends of the connection links 10 and the arm 5 and the engagement links 11 are swingably connected to the arms 5. is there. The arm 5, the rising link 9, the connecting link 10, and the engaging link 11 constitute a slightly parallelogrammatic link mechanism. Then, each engagement link 11
An engaging claw 12 extending upward is projected from the upper end of the front side of the engaging claw 12.
A slightly U-shaped engaging groove 13 that is open upward is formed by. A first pin hole 14 penetrating left and right is opened at the center of rotation of the connecting link 10 and the engaging link 11, and the center of rotation of the engaging link 11 and the arm 5 is similarly left and right. The 2nd pin hole 15 which penetrated is opened.
The first connecting pin 16 is inserted into the pin hole 14, and the second connecting pin 17 is inserted into the pin hole 15.

The bucket 18 shown in FIG. 1 has a conventionally well-known shape, and a pair of flat plate-like brackets 19 are fixed in parallel to the outer circumference of the bucket 18. Each bracket 19 has a third
The pin holes 20 and the fourth pin holes 21 are opened, and a total of four pin holes 20 and 21 are provided. The axis of the pair of pin holes 20 and the axis of the pair of pin holes 21 are arranged in parallel. The distance between the axes of the pair of pin holes 20 and the pair of pin holes 21 is set to match the distance between the axes of the pin holes 14 and 15. A hooking pin 22 that is bridged between the two brackets 19 is fixed between the pair of brackets 19 and at a position closer to the main body of the bucket 18 than the pin hole 20. The hooking pin 22 has a round bar shape, and its outer diameter is formed to be slightly smaller than the groove width of the engaging groove 13. The axis of the hooking pin 22 is arranged to be parallel to the axes of the pair of pin holes 20.

FIG. 2 is an enlarged view showing the bucket attaching / detaching mechanism near the tip of the arm 5. Pins 25 are inserted through the tip of the cylinder rod 8 to the left and right, and are located on the left and right of the cylinder rod 8 to form the connecting links 1 respectively.
0 is rotatably inserted in the pin 25. Located on the left and right of both connecting links 10, the start-up link 9 is further pin 2
It is inserted through 5 so as to be rotatable. These rising links 9 extend downward, and the lower ends of the rising links 9 are rotatably connected by a pin 26 near the tip of the arm 5. Further, the engaging links 11 are arranged on the left and right of the tip of the arm 5, and the engaging links 11 extend upward, respectively, and the upper end of each engaging link 11 and the tip of the connecting link 10 are connected. Are rotatably connected, and a curler 27 is interposed between the tips of the two connecting links 10. Next, slightly L-shaped engaging claws 12 are projected from the middle of the front side of the two engaging links 11 (on the left side in FIG. 2) to the upper side. The upper end of the engaging claw 12 is substantially aligned with the upper end of the engaging link 11. Since the engaging claws 12 project toward the front of the engaging link 11, there is a slight U between them.
A letter-shaped engaging groove 13 is formed, and the engaging groove 13 has a shape extending to a semi-circular curve at the upper end of the engaging link 11.

FIG. 3 is a perspective view showing the relationship in length between the bracket 19 fixed to the bucket 18 and the respective portions of the engagement link 11 connected to the arm 5.
A pair of flat plate-like brackets 19 are fixed to the back surface of the bucket 18 with a space therebetween.
The space inside 9 is set to A. And pin hole 2
The distance between the axis of 0 and the axis of the pin hole 21 is set to B, and the distance between the axis of the pin hole 20 and the axis of the hooking pin 22 is set to C. The distance between the left and right outer sides of the pair of engagement links 11 is set to A, and the distance between the shaft centers of the pin holes 14 and 15 in the engagement link 11 is set to B. The distance between the axis of the pin hole 14 and the groove center of the engaging groove 13 is set to C.

Further, FIG. 4 is a plan view showing the relationship between the distances A and B of the respective members described in FIG. As can be seen in this figure, the entire pair of engagement links 11 can be inserted into the space between the pair of brackets 19 and 19, and the entire engagement link 11 can be fitted between the brackets 19. It is set.

Next, referring to FIG. 5, the engagement link 11 is fitted into the bracket 19, and the both are connected to the connecting pin 16 and the connecting pin 1.
It is sectional drawing in the state connected by 7. In this state, the connecting pin 16 is inserted into the pin holes 14 and 20, the connecting pin 17 is inserted into the pin holes 15 and 21, and the bucket 18 is attached to the tip of the arm 5. It is a thing. At the tip of the arm 5, there is a shaft support 3 which has a flange shape on both sides which is opened through in the left-right direction.
5 is stuck. A cylindrical bearing 36 is fixed to the side surface of one of the engagement links 11 at a position coaxial with the pin hole 15. The bearing 36 is rotatably inserted into the shaft support 35. ing. The tip of the bearing 36 extends to the other side surface of the arm 5, and the bearing 36
The side surface of the other engagement link 11 is closely attached to the tip of the other end, and the other engagement link 11 and the bearing 36 are screwed by a screw 37. In addition, one engagement link 11
A cylindrical shaft support 38 is fixed at a position coaxial with the pin hole 14, and the side face of the other engaging link 11 is closely attached to the tip of the shaft support 38. The engagement link 11 and the shaft support 38 on the other side are fixed by screws 39. The bearing 36, the shaft support 38, the screw 37, and the screw 39 enable the engagement links 11 on both sides to simultaneously swing with respect to the arm 5 about the shaft support 35.

The shaft center of the pipe-shaped bearing 36 is aligned with the shaft center of the pin hole 15 opened in the engagement link 11. Further, the axial center of the pipe-shaped shaft support 38 is aligned with the axial center of the pin hole 14 opened in the engagement link 11. Further, a connecting hole opened at the tip of the connecting link 10 is rotatably inserted through the outer periphery of the shaft support 38, and a pipe-shaped curler 27 is interposed between the two connecting links 10. The curler 27 regulates the two connecting links 10 so as not to come close to each other. With such a configuration, the connecting pin 16 is inserted into the pin holes 14 and 20, the connecting pin 17 is inserted into the pin holes 15 and 21, and the engaging link 11 and the bracket 19 are inserted by the connecting pins 16 and 17. And are pin-connected. In addition,
Split pins 40 and split pins 41 are inserted at the tips of the inserted connecting pins 16 and 17 in a direction perpendicular to the axis thereof,
The split pin 40 and the split pin 41 connect the connecting pin 1
6. The connecting pin 17 is prevented from falling off.

Next, a procedure for mounting the bucket 18 on the tip of the arm 5 will be described with reference to FIGS. 6, 7, 8 and 9. In this procedure, first, as shown in FIG. 7, the bucket 18 is placed on the ground, and a worker rides on the driver's seat of the vehicle body 1, swings the boom 3 and the arm 5 back and forth, and the excavator works A single member can connect the bucket 18 to the tip of the arm 5.

First, FIG. 7 shows a state in which no accessory for the civil engineering work (here, the bucket 18) is attached to the tip of the arm 5, and the bucket 18 will be moved to the arm 5 from now on.
Will be attached to the tip of. Before starting this mounting work, first activate the bucket cylinder 7,
The cylinder rod 8 is extended to the maximum extent, and the engagement link 11 is tilted forward as much as possible. This engagement link 1
1 is inclined, the engaging claw 12 is directed downward, and U
The engagement groove 13 formed in a V shape is located at the tip of the arm 5.

With this preparation completed, the hydraulic cylinder 4 and the hydraulic cylinder 6 are operated cooperatively to swing the boom 3 and the arm 5 up and down, and the tip of the engaging link 11 approaches the bracket 19 of the bucket 18. Let Then, if both sides of the engagement link 11 are positioned between the pair of brackets 19, the open end of the engagement groove 13 is caught by the hook pin 2.
2 to adjust, then boom 3 and arm 5
Is operated to push the hooking pin 22 into the engaging groove 13 to move the engaging link 11 obliquely downward to the left in FIG. Thus, the hook pin 2 is inserted into the groove of the engaging groove 13.
The state in which the two are fitted together is shown in FIG. In this state, the hooking pin 22 is fitted inside the groove of the engaging groove 13, so that the relative positions of the engaging link 11 and the bucket 18 are determined by the groove of the engaging groove 13 and the hooking pin 22. You can

As described above, the hydraulic cylinder 4, the hydraulic cylinder 6, and the bucket cylinder 7 are controlled to keep the hooking pin 22 rotating while the outer periphery of the hooking pin 22 is kept in contact with the depth of the engaging groove 13. The engagement link 11 is rotated in the clockwise direction as shown by the arrow in FIG.
Then, the engagement link 11 is fitted between the brackets 19, and the tip of the arm 5 is fitted between the left and right brackets 19.

As already shown in FIGS. 3 and 4, the spacing between the pin hole 14 and the engaging groove 13 formed in the engaging link 11 and the bracket 19, and the pin hole 20 and the hooking pin 22.
Since the distance between each is C, the hooking pin 22
When the engagement link 11 is rotated around the
The axis line of the pin hole 20 and the axis line of the pin hole 20 always match. At the same time, the distance between the pin holes 14 and 15 and the pin hole 20,
Since the intervals of 21 are B, respectively, if the axes of the pin holes 14 and 20 coincide, the axes of the pin holes 15 and 21 also coincide. In this way, the pin hole 1
4 and the pin hole 20 have the same axis, and the pin holes 15 and 2
When the axes of 1 match, the connecting pin 16 is inserted into the pin holes 14 and 20 from the side surface of the bracket 19, and the connecting pin 17 is inserted into the pin holes 15 and 21. The engagement pins 11 and the bracket 19 are connected by the connecting pins 16 and 17.
Is pin-connected, and as a result, the bucket 18 is connected to the tip of the arm 5.

Such alignment can be performed by an operator on the body 1 of the excavator without the need for another operator by expanding or contracting the hydraulic cylinder 4, the hydraulic cylinder 6, and the bucket cylinder 7, respectively. it can. And this alignment can be performed only by swinging the hooking pin 22 around the engagement groove 13, and can be completed by a simple operation.

After that, as shown in FIG. 9, the bucket cylinder 7 is contracted, and the hydraulic cylinders 4 and 6 are operated to lift the bucket 18 upward so that various civil engineering works can be performed. .

By this series of procedures, the bucket 18 can be attached to the tip of the arm 5. In order to remove the bucket 18 from the tip of the arm 5, the connecting pin 16 and the connecting pin 17 are pulled out by the procedure shown in FIGS. 9, 8 and 7 contrary to the above, and then the engaging groove 13 is hooked. The bucket 18 can be removed from the tip of the arm 5 by pulling it away from the pin 22.

[0037]

As described above, according to the invention of the present application, the front and rear pin holes are positioned by the engaging groove of the engaging link attached to the tip of the arm and the hooking pin of the bucket even though the structure is simple. Can be done easily.

In addition, in connecting the arm and the bucket, since the two pins are connected by pins, the connection between the two is extremely strong, and the possibility of deforming the member is reduced even when a large force is applied to the bucket. Therefore, in order to easily attach and detach the bucket, an adapter is provided at the tip of the arm, and the bucket can be firmly held as compared with a mechanism in which the adapter attempts to attach and detach the bucket.

[Brief description of drawings]

FIG. 1 is an overall perspective view showing a structure in which a bucket is connected to an arm of an excavator.

FIG. 2 is an enlarged perspective view showing the configuration of each part near the tip of the arm.

FIG. 3 is an enlarged perspective view showing the configuration of the vicinity of the tip of the arm and the bucket.

FIG. 4 is a plan view showing the relationship between the tip of the arm and the length of each member of the bucket.

FIG. 5 is a cross-sectional view showing a state in which an engagement link and a bracket are combined.

FIG. 6 is a perspective view showing a state in which an engagement groove and a hooking pin are fitted together.

FIG. 7 is an explanatory diagram showing a state before the bucket is brought close to the tip of the arm.

FIG. 8 is an explanatory diagram showing a state in which the arm and the bucket are connected by a connecting pin.

FIG. 9 is an explanatory diagram showing a state in which a bucket connected to the arm is lifted. 1 Car Body 3 Boom 5 Arm 7 Bucket Cylinder 9 Start-up Link 10 Connecting Link 11 Engaging Link 12 Engaging Claw 13 Engaging Groove 14 First Pin Hole 15 Second Pin Hole 16 First Connecting Pin 17 Second Connecting pin 18 Bucket 19 Bracket 20 Third pin hole 21 Fourth pin hole 22 Hooking pin

Claims (5)

[Claims] 1. A movable vehicle body, a boom vertically swingably connected to the vehicle body, an arm vertically swingably connected to a tip of the boom, and a arm detachably attached to the tip of the arm. In a construction machine consisting of engaged buckets, a pair of engagement links whose lower ends are rotatably connected to the left and right of the tip of an arm, and the engagement links are made to project upward at the front side of each engagement link. An engaging claw, a bucket cylinder in which its base is connected to the rear of the arm, and its cylinder rod is connected to the upper parts of both engaging links, a first pin hole opened in the upper part of each engaging link, and an arm of the arm. The second end opened at a position coaxial with the center of rotation of the engagement link
Pin holes, a pair of brackets fixed to the back surface of the bucket at intervals, hook pins provided between both brackets, and a third pin hole opened at a position close to the hook pins of each bracket, A fourth pin hole opened at a position apart from the hook pin of each bracket and a first pin and a third pin hole when the hook pin is inserted into an engagement groove formed by the engagement claw and the engagement link. The first connecting pin that is commonly inserted in the pin hole of the above, and the second and fourth pin holes when the hooking pin is inserted in the engaging groove formed by the engaging claw and the engaging link. And a second connecting pin that is inserted therethrough. 2. A movable vehicle body, a boom vertically swingably connected to the vehicle body, an arm vertically swingably connected to a tip of the boom, and an arm detachably attached to a tip of the arm. In a construction machine consisting of a bucket to be engaged, a cylindrical bearing rotatably inserted into the tip of the arm so that the axis line is perpendicular to the longitudinal direction of the arm, and penetrates through the shaft core of the bearing. Second pin holes that are opened, a pair of engagement links that are located on the left and right sides of the arm and that connect their lower parts to both ends of the bearing, and engagement that protrudes upward at the front side of each engagement link Connect the claw, the first pin hole opened at the top of each engagement link, and its base to the rear of the arm,
A bucket cylinder in which the cylinder rod is connected to the upper part of both engagement links, a second pin hole opened at the tip of the arm at a position coaxial with the rotation center of the engagement link, and a gap on the back surface of the bucket. , A pair of brackets that are fixed by placing, and a hook pin provided between both brackets,
It is formed by a third pin hole opened at a position close to the hook pin of each bracket, a fourth pin hole opened at a position separated from the hook pin of each bracket, and an engaging claw and an engaging link. To the engaging groove formed by the engaging claw and the engaging link, and the first connecting pin that is commonly inserted into the first and third pin holes when the hooking pin is inserted into the engaged groove. A bucket attaching / detaching mechanism of a construction machine, comprising a second connecting pin that is commonly inserted into the second and fourth pin holes when the hooking pin is inserted. 3. The bucket of a construction machine according to claim 1, wherein the distance between the first and second pin holes is set to be substantially the same as the distance between the third and fourth pin holes. Detachable mechanism. 4. The distance outside the engagement links provided on the left and right of the arm is set to be substantially the same as the distance inside the pair of brackets fixed to the bucket.
And a mechanism for attaching and detaching a bucket of a construction machine according to the above item 2. 5. The interval between the engaging groove formed by the engaging claw and the engaging link and the first pin hole is set to be substantially the same as the interval between the hooking pin fixed to the bracket and the third pin hole. The attachment / detachment mechanism for a bucket of a construction machine according to claim 1 or 2, characterized in that.