JPH0715173B2 - Excavator with extendable bucket - Google Patents

Description

The present invention relates to an excavator, and more particularly to an excavator characterized by allowing a bucket for excavating earth and sand to extend and contract in the length direction of an arm. The present invention relates to an excavator having a bucket.

[Conventional technology]

In the civil engineering work, most of the work involves excavating earth and sand and excavating holes. An excavator (also called a backhoe) is actively used to modernize civil engineering work, which is such excavation work, and to efficiently perform the work.

In many conventional excavators, a boom having a slightly V shape is swingably attached to a vehicle body to which a crawler and wheels are attached, and a slightly linear arm is attached to the tip of the boom. This arm was vertically swingably connected to the boom, and a bucket was attached to the tip of the arm. With this configuration, by operating the boom, the arm, and the bucket in cooperation with each other, the bucket can be pushed into the soil, and then the bucket can be pulled up to dig the earth and sand. The basic structure of this excavator has been actively used, and its shape has hardly changed. And, in order to operate these buckets, arms, and booms, it is usually possible to perform the digging work by operating each of the three hydraulic cylinders.

Using such an excavator that has been actively used,
In order to deepen the depth of the trenches and holes to be dug, the boom, arm and length must be increased respectively. Also, at work sites where the bucket is extended from the riverbank to dig up the soil on the opposite bank, the length of the boom and arm is fixed in conventional excavators, so the length set by the boom and arm should be longer than the length set by the boom and arm. The bucket did not reach. As described above, in the conventional configuration, the depth to be dug by the bucket and the distance reached by the bucket are naturally limited.

In the work with limited conditions as described above, when trying to dig a groove or hole deeply or when trying to reach the long position of the bucket, it is necessary to increase the length of the boom and the arm, respectively. This is theoretically possible. However, if the boom and arm are designed to be long, the entire length of the boom and the arm will be long when the excavator moves, which makes it difficult to carry.

Further, after such excavation work, the excavated earth and sand must be moved from the front of the vehicle body toward the rear with a bucket. In this transfer, the bucket is rotated with respect to the vehicle body, but the boom must be raised vertically at the time of turning, and if the boom is raised vertically, the top height of the boom rises, and the electric wires and other This made it dangerous to work with because it came into contact with the structure.

In the conventional excavator, since the boom and the arm are fixed in length, the work range is limited. For this reason, the same applicant as the present invention has proposed an excavator that allows the arm to be extended and retracted so that the bucket attached to the tip of the arm can be pushed down to a deeper position or can be reached for a long time. Wishhei 1 year 10
No. 7990). However, in this newly proposed excavator, the inner boom expands and contracts with respect to the boom, so that the hydraulic cylinder for controlling the angular position of the bucket must be moved at the same time.
For this reason, a part of the hydraulic cylinder is designed to be movable with respect to the outer boom, and the base of the hydraulic cylinder is moved by front or rear wires for synchronization.
However, in this configuration, the base of the hydraulic cylinder cannot be moved in synchronism with the inner boom unless the front and rear wires are always pulled, and the structure becomes complicated.

[Means for solving problems]

In view of the above-mentioned drawbacks, the present invention provides a movable vehicle body, a boom connected to the vehicle body so as to be vertically swingable, and a hollow outer portion connected to the boom so as to be vertically swingable. An arm, an inner arm inserted into the outer arm so as to be slidable in its length direction, a bucket connected to the tip of the inner arm, and a hydraulic cylinder for expansion and contraction interposed between the outer arm and the inner arm. , A slider that can move in the length direction outside the outer arm, a hydraulic cylinder interposed between the bucket and the slider, a synchronizer that connects the tip of the inner arm and the slider, and a rear portion of the outer arm. The first wheel pivotally supported, the second wheel pivotally supported on the front portion of the outer arm, the tip end thereof is coupled to the slider, and the rear end thereof is coupled to the rear end of the inner arm. Wheel and first The wheel there is provided a drilling machine having a stretchable bucket is composed of a connecting band with flexibility is wound around the S-shaped.

Further, in the present invention, there is a pair of first wheels, and each first wheel
Wheels are respectively supported on both sides of the rear part of the outer arm, there are a pair of second wheels, each second wheel is supported on both sides of the front part of the outer arm, and there are two connecting belts. The tip of each is connected to the slider, the rear end of each connecting band is connected to the rear part of the inner arm, and one connecting band is wound around one of the first and second wheels in an S shape and the other is connected to the other. The connecting band provides an excavator having an extendable bucket, which is characterized by being wound around the other first and second wheels in an S shape.

Further, in the present invention, the first wheel is a rear portion of the outer arm and is pivotally supported inside thereof, and the second wheel is a front portion of the outer arm and is pivotally supported inside thereof. The second wheel provides an excavator having a retractable bucket characterized by being located outside the inner arm.

Further, the present invention provides an excavator having an extendable bucket, wherein the first and second wheels are sprocket wheels and the connecting band is a chain.

Further, in the present invention, both sides of the upper surface of the outer arm are formed as guide edges extending in the left-right direction and extending in the length direction of the outer arm, and the cross-section with the respective openings facing each other is formed on both sides of the slider. The U-shaped guide is fixed,
(EN) An excavator having an extendable bucket characterized in that a slider is restricted to move only in the length direction of an outer arm by fitting each guide to each guide edge.

Further, according to the present invention, fixing screws are projected at both ends of the synchronous body that connects the slider and the inner arm, and each screw is connected to the slider and the inner arm by a nut so that the length can be adjusted. An excavator having a retractable bucket is provided.

[Action]

According to the present invention, the outer arm is connected to the tip of the boom, and the inner arm is slidably inserted in the length of the outer arm. With this configuration, in order to reach the deeper position of the bucket, the total length of the bucket can be increased by pushing the inner arm out of the outer arm by the hydraulic expansion / contraction mechanism. This allows the bucket to reach a deeper position or a longer position. When the inner arm is pushed out with respect to the outer arm, the slider moves the outer arm in synchronization with the extension amount of the inner arm because the synchronizing body is interposed between the tip of the inner arm and the slider. However, the base of the hydraulic cylinder for the bucket mounted on the slider moves on the side surface of the outer arm with the same movement amount. Therefore, even if the inner arm extends, the bucket angle can always be kept the same.

When the inner arm is to be housed in the outer arm, the connecting belt connected to the rear portion of the inner arm acts to pull up the slider while rolling the first and second wheels. Therefore, the slider moves the outer arm in synchronization with the reduction amount of the inner arm, and the base portion of the bucket hydraulic cylinder mounted on the slider moves on the side surface of the outer arm with the same movement amount. Therefore, even if the inner arm extends, the bucket angle can always be kept the same.

Further, since the first and second wheels and the two connecting bands are provided, when the inner arm slides with respect to the outer arm,
The slider can be moved smoothly.

In addition, since the first and second wheels are axially supported inside the outer arm, each wheel is not exposed, is not damaged, and can be used for a long period of time.

Further, since the first and second wheels are sprocket wheels and the connecting band is a chain, the interlocking can be performed strongly, and breakage is reduced.

Further, guide edges are formed on both sides of the upper surface of the outer arm, and U-shaped guides are fixed on both sides of the slider, and each guide is fitted to each guide edge.
The slider can move only in the length direction without being disengaged from the outer arm.

Then, fixing screws are projected at both ends of the synchronous body that connects the slider and the inner arm, and the looseness can be adjusted with these screws, so that tension can always be applied to the flexible connecting band. it can. Therefore, the connecting band does not loosen, there is no play in the movement of the slider, and the slider can be moved accurately.

〔Example〕

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

FIG. 1 is an external perspective view showing an embodiment of an excavator according to the present invention.

Crawlers 2 are attached to the lower left and right sides of a vehicle body 1 that houses an engine, a hydraulic pressure generator, and the like, and the crawler 2 allows the vehicle body 1 to move freely. A boom 3 bent in a V shape is connected to the center of the front surface of the vehicle body 1, and a hydraulic cylinder 4 for depression is interposed between the center legs of the boom 3 and the front left and right sides of the vehicle body 1. There is. A linear outer arm 5 is swingably connected to the upper end of the boom 3, and a swing hydraulic cylinder 6 is interposed between the rear portion of the outer arm 5 and the center of the rear surface of the boom 3. is there. The outer arm 5 is formed by bending a steel plate and has a tubular shape with a slightly quadrangular cross section, and an inner arm 7 having a quadrangular cross section is inserted inside the outer arm so as to be slidable along its length direction. I am allowed. A bucket 8 is swingably connected to the tip of the inner arm 7.

The levers 9 and 10 for forming a link mechanism are connected between the tip of the inner arm 7 and the rear portion of the bucket 8, and both levers 9 and 10 have a slightly triangular shape with their tips tied together. The cylinder rod 12 of the bucket cylinder 11 is connected to the apexes of both levers 9 and 10. On the upper surface of the outer arm 5, there is combined a slider 13 which can move in the lengthwise direction, and on the upper surface of the slider 13, a pair of slightly trapezoidal shaft support plates 15 are fixed. is there. A base portion of a bucket cylinder 11 is inserted between both shaft support plates 15, and the shaft support plate 15 and the bucket cylinder 11 are swingably connected by a pin 16.

A slightly triangular fixing tool 17 is fixed to the tip of the inner arm 7 near the lever 9, and a flat shape is formed between the fixing tool 17 and the slider 13. An interlocking bar 18 as a synchronizing body is interposed.

Next, FIG. 2 and FIG. 3 show the internal structure of the outer arm 5 in this embodiment. 4 shows the interlocking mechanism in this embodiment, and FIG. 5 shows A in FIG.
FIG. 7 is a cross-sectional view taken along arrow A.

At the center of the inside of the inner arm 7, a hydraulic cylinder 20 for expansion and contraction is inserted so as to be parallel to the lengthwise direction,
The base of the hydraulic cylinder 20 is fixed to the rear end (right side in FIG. 2) of the outer arm 5, and the cylinder rod 21 of the hydraulic cylinder 20 is connected to the center of the inner surface of the inner arm 7.

Next, small rollers 22 and 23 for rolling are pivotally supported on the upper and lower surfaces of the outer arm 5 so that the inner arm 7 can move smoothly with respect to the outer arm 5 by these rollers 22 and 23. Held in. Further, at the rear end of the outer arm 5 and at the left and right positions thereof, sprocket wheels 24 and 25 as first wheels, half of which are exposed on the upper surface of the outer arm 5, are pivotally supported. Sprocket wheels as second wheels are provided on both sides of the inner surface of the arm 5 and on both sides of the outer surface of the inner arm 7.
26 and 27 are held so as to be pivotally supported by the outer arm 5. The tip of the chain 28 serving as a connecting band is connected to the rear end of the slider 13, and the chain 28 is reversed by the sprocket wheel 24, and the inner arm 5
It is inserted between the inner arm 7 and the inner arm 7, extends in the direction of the bucket 8 and is inverted by the sprocket wheel 26, and its rear end is connected to the rear end of the inner arm 7. A chain 29 as a connecting band is connected to the slider 13 at its rear end, and then the chain 29 is reversed by a sprocket wheel 25 and inserted between the outer arm 5 and the inner arm 7 to extend in the bucket 8 direction. , The sprocket wheel 27 is reversed, and its rear end is connected to the rear end of the inner arm 5.

Next, the structure near the slider 13 will be described with reference to FIGS.

The outer arm 5 is composed of a body portion 55 formed by bending a steel plate into a U shape, and a roof portion 56 fixed so as to close an opening on the upper surface of the body portion 55. The left and right end portions of the roof portion 56 slightly project from the side surfaces of the body portion 55, and the roof portion 56
The left and right ends of the slider 13 are combined so that the slider 13 does not drop.

This slider 13 is composed of a slightly H-shaped main body 30 whose center width is set to be the same as the width of the outer arm 5,
The lower surface of the main body 30 has a sliding body formed of reinforced synthetic resin or the like.
57 is fixed, and the lower surface of the sliding body 57 is the roof portion 56.
The sliding body 57 allows the slider 13 to slide smoothly. The shaft support plate 15 is fixed in parallel to the center of the upper surface of the main body 30 at intervals, and the base of the bucket cylinder 11 is inserted between the shaft support plates 15. Also, flat plate-shaped mounting plates 58 and 59 are fixed to the left and right sides of the main body 30, and the guide plates 31 that engage with the ends of the roof portion 56 are attached to the mounting plates 58 and 59, respectively. , 32 are fixed with screws 60, 61.

Inside the lower parts of the guide bodies 31, 32, concave portions 62, 63 formed in a U-shape are provided, and L-shaped sliding bodies 64, 65 formed of reinforced synthetic resin or the like are formed on the inner walls of the concave portions 62, 63. It is fitted. The sliding bodies 64, 65 can guide the slider 13 while contacting the end of the roof portion 56. Then, the slider 13 is covered by the guide members 31 and 32.
56, that is, it can be moved so as not to come off the upper surface of the outer arm 5. A connecting hole 33 is horizontally opened at the center of the main body 30 so as to be perpendicular to the length direction, and joint holes 6 are formed on the left and right sides of the connecting hole 33 in parallel.
6 and 67 are opened.

Next, the interlocking bar 18 will be described.
For example, it is formed of a thin metal band having high rigidity, and fixing screws 34 and 35 for applying tension are fixed to the front end and the rear end of the interlocking bar 18 by welding or the like. The fixing screw 35 is inserted into the connecting hole 33, and the main body 30
At the rear part, nuts 37, 38 are doubled and screwed and fixed. Further, the fixing screw 34 is fixed to the fixing portion 17
It is inserted into a fixing hole 39 opened on the vertical surface of the nut, and nuts 40 and 41 are double tightened and fixed to the fixing screw 34. In this way, the connection bar 18 is such that the gap between the fixed portion 17 and the slider 13 is adjusted by the fixing screws 34, 35, and the nuts 37, 38, 4
The pulling force can be freely set by adjusting 0 and 41, respectively.

In addition, long screws 6 are attached to the tips of the chains 28 and 29, respectively.
8 and 69 are connected, the long screw 68 is inserted into the joint hole 66, and a nut 70 is doubled and fixed by screwing at the rear portion of the main body 30. And
The long screw 69 is inserted into the joint hole 67, and the main body 30
At the rear part, the nut 71 is doubled and screwed and fixed.

Next, the operation of this embodiment will be described.

The crawler 2 is driven to move the vehicle body 1 to a place where a groove or a hole is to be dug down. Then, align the bucket 8 with the position where you want to dig, and set the hydraulic cylinders 4, 6, 11
The bucket 8 can be rocked by operating so as to cooperate with each other, and the bucket 8 can excavate the earth and sand. This operation is the same as that of the conventional excavator.

Next, in order to deepen the hole or groove to be dug, the bucket 8
Must be controlled to move to a deeper position. In this case, the hydraulic cylinder 20 is operated and the cylinder rod 21 is pushed out. Then, as the hydraulic cylinder 20 and the cylinder rod 21 extend, the inner arm 7 is pushed out of the outer arm 5, and the inner arm 7 slides from the outer arm 5 as shown in FIG. 7 to FIG. Become. Therefore, since the bucket 8 moves to a position longer than the base of the outer arm 5, the bucket 8 can be dug down to a deep position.

During this operation, when the inner arm 7 moves with respect to the outer arm 5, the interlocking bar 18 fixed to the tip of the inner arm 7
Means pulling the slider 13 and moving the slider 13 in the length direction on the upper surface of the outer arm 5. When the slider 13 is moved, the guide bodies 31 and 32 fixed to the left and right of the main body 30 guide the left and right sides of the outer arm 5 by contacting the side surfaces thereof. Does not come off from the top surface. Further, since the interlocking bar 18 does not extend its length, as long as it is pulled by the fixture 17, the slider 13
Will move in synchronization with the movement of the inner arm 7 and the movement amount thereof.

In this way, when the hydraulic cylinder 20 is actuated and the cylinder rod 21 is pushed out, the inner arm 7 is pushed out by the outer arm 5, but the bucket cylinder 11 is moved at the same time in synchronization with the sliding amount. Since the angle of is moved while being held at the same angle, it can be operated without any discomfort during the excavation operation.

When pulling up the soil excavated by the bucket 8, the hydraulic cylinder 20 is first operated to reduce the cylinder rod 21. Then, the inner arm 7 is pulled inward of the outer arm 5. At this time,
Since the chains 28, 29 are connected to the rear part of the inner arm 7, the chains 28, 29 are pulled toward the base of the outer arm 5, and the chains 28, 29 are sprocket wheels 26, 27.
The slider 13 is turned upside down, and then turned upside down by the sprocket wheels 24 and 25 and pulled, and the slider 13 is pulled up toward the upper end of the outer arm 5.

Therefore, similarly to the above, at the same time that the inner arm 7 moves, the bucket cylinder 11 also moves at the same speed by synchronizing the movement amount. Therefore, the bucket 8 is pulled up with the holding angle kept the same, and thus the dug earth and sand is not dropped. After that, by operating the hydraulic cylinders 4 and 6 and the bucket cylinder 11 in cooperation with each other, the earth and sand excavated by the bucket 8 is transferred to a truck waiting at the rear of the vehicle body 1 or moved to another place. Can be changed.

Next, FIGS. 9 and 10 show another embodiment of the synchronizing mechanism of the present invention. 9 and 10, the same mechanism as that of the first embodiment is designated by the same reference numeral as that of the first embodiment, and the description thereof is omitted.

FIG. 9 is a side view in which a part of the outer arm 5 and the inner arm 7 is cut, and FIG. 10 is an exploded perspective view of the synchronization mechanism.

At a position near the tip of the inner arm 7 and close to the lever 9, a slightly triangular fixing tool 17 is fixed,
The fixture 17 and the main body 30 of the slider 13 are connected by a pipe-shaped connecting body 40 having a rectangular cross section. The connecting body 40 is formed so as to have stress resistance so that it does not buckle or deform even if it is compressed or stretched in its length direction. The stress applied to the connecting body 40 is about the pulling force required when the bucket 8 is excavated. The feature of the second embodiment shown in FIG. 9 is that the wire or the like connected to the rear portion of the slider 13 required in the first embodiment is unnecessary.

The connecting body 40 is composed of a rod 41 and fixing bolts 42 and 43 connected to both ends of the rod 41. This rod 41
Has a hollow pipe shape whose cross section is quadrangular, and has insertion grooves 44 and 45 cut in groove shapes at the centers thereof at both ends thereof. The fixing bolt 42 is inserted into the insertion groove 44, and the two are connected by a pin 46. The fixing bolt 43 is inserted into the insertion groove 45, and both are connected by a pin 47.

Next, the threaded portion of the fixing bolt 42 is inserted into the connecting hole 33, and two fixing nuts 4 are formed on the rear surface of the main body 30.
8 and 49 are screwed in, and this fixing bolt 42 has nuts 48 and 49.
It is firmly fixed to the body 30 by. In addition, the screw portion of the fixing bolt 43 is inserted into the fixing hole 39 of the fixing tool 17,
Two nuts 50 and 51 are screwed in on the back surface, and the fixing bolt 43 is fixed by the nuts 50 and 51.
It is firmly fixed to. With this configuration, the rod 41 is a pin
It can be swung up and down by 46 and 47, but it is firmly fixed so that it cannot expand or contract in the length direction, and it has a steel structure that can not extend or contract the length.

In this embodiment, when the hydraulic cylinder 20 is operated and the cylinder rod 21 is extended, the rod 41 is pulled by the fixture 17 and the main body 30 of the slider 13 is pulled out accordingly, so that the bucket 8 is kept at the same angle. The base of the bucket cylinder 11 is moved as it is.
Therefore, the inner arm 7 can be extended with respect to the outer arm 5 without changing the angle of the bucket 8.
Also, operate the hydraulic cylinder 20 to activate the cylinder rod.
When 21 is contracted, the inner arm 7 connected to the cylinder rod 21 is pulled inside the outer arm 5. At this time, since the rod 41 fixed to the fixture 17 has rigidity, the main body 30 is pushed up without shortening its length, and thus the base of the bucket cylinder 11 is pushed up toward the rear of the outer arm 5. Become. Therefore, bucket 8
While the angle of is held at that angle position, the base of the bucket cylinder 11 can be moved in synchronism with the movement of the inner arm 7, and the bucket cylinder 11 can be moved with the same feeling as the operation of the normal bucket 8. it can.

Unlike the first embodiment, this embodiment has a small number of parts and has a simple structure.

〔effect〕

Since the present invention is configured as described above, when performing earth and sand excavation work using an excavator, it is possible to push down the bucket to a deeper position or to reach a long distance, so excavation of earth and sand The working range in work can be expanded.

In addition, the length of the boom can be made the same as the length of the conventional excavator, while the distance that the bucket can be extended becomes longer.Therefore, when moving the excavator or standing the boom vertically. When turning, the height of the boom does not become high, it will not collide with electric wires or structures,
It is possible to prevent an accident from occurring.

[Brief description of drawings]

FIG. 1 is a perspective view showing the appearance of an excavator showing an embodiment of the present invention, FIG. 2 is a side view showing the structure of an outer arm, FIG. 3 is a plan view of the same as above, and FIG. FIG. 5 is an exploded perspective view showing the structure, FIG. 5 is a sectional view taken along the line AA in FIG. 2, FIG. 6 is an exploded perspective view showing the structure of the synchronizing mechanism, and FIG. FIG. 8 is a side sectional view showing a state in which its length is shortened, FIG. 8 is a side view showing a state in which the same inner arm is pushed out from the outer arm to maximize its total length, and FIG. 9 is another view of the present invention. FIG. 10 is a side view with a part of the outer arm cut off showing an embodiment, and FIG. 10 is an exploded perspective view of the same synchronizing mechanism. 1 ... Body, 3 ... Boom, 5 ... Outer arm, 7 ... Inner arm, 8 ... Bucket, 11 ... Bucket cylinder,
13 ...... Slider, 17 ...... Fixture, 18 ...... Interlocking bar as synchronous body, 24, 25 ...... Sprocket wheel as first wheel, 26,27 ...... Sprocket wheel as second wheel, 28 , 29 …… Chain as connecting band, 30 …… Main body, 35,36 …… Fixing screw, 37,38 …… Nut, 40 …… Connecting body as synchronous body.

Claims (6)

[Claims] 1. A movable vehicle body, a boom connected to the vehicle body so as to be vertically swingable, an outer arm having a hollow interior connected to the boom so as to be vertically swingable, and an outer body. An inner arm slidably inserted into the arm, a bucket connected to the tip of the inner arm, a hydraulic cylinder for expansion and contraction interposed between the outer arm and the inner arm, and an outer arm A slider that can move in the length direction outside of the, a hydraulic cylinder interposed between the bucket and the slider, a synchronizing body that connects the vicinity of the tip of the inner arm and the slider, and is rotatably supported at the rear of the outer arm. The first wheel, the second wheel pivotally supported on the front part of the outer arm, the tip end of which is connected to the slider and the rear end of which is connected to the rear end of the inner arm, and the first wheel and the second wheel On the wheel Drilling machine having a stretchable bucket, characterized in that it is composed of the connecting band and with a wound a flexible shape. 2. A pair of first wheels, each first wheel being pivotally supported on both sides of a rear portion of the outer arm, a second wheel being a pair, and each second wheel being on both sides of a front portion of the outer arm. Each of them is pivotally supported, and there are two connecting belts. The tip of each connecting belt is connected to a slider. The rear end of each connecting belt is connected to the rear part of the inner arm. The expandable bucket according to claim 1, wherein the first and second wheels are wound in an S shape, and the other connecting band is wound in an S shape on the other first and second wheels. Excavator having. 3. A first wheel is a rear part of the outer arm and is pivotally supported inside thereof, and a second wheel is a front part of the outer arm and is pivotally supported inside thereof. An excavator having a retractable bucket according to claim 1 or 2, wherein the wheel of (1) is located outside the inner arm. 4. The excavator with a retractable bucket according to claim 1, 2 or 3, wherein the first and second wheels are sprocket wheels and the connecting band is a chain. 5. Both sides of the upper surface of the outer arm are projected to the left and right,
In addition, it is formed as a guide edge that extends in the length direction of the outer arm.On both sides of the slider, guides with U-shaped cross sections facing each opening are fixed, and each guide is attached to each guide edge. The excavator having an extendable bucket according to claim 1, wherein the slider is regulated so as to move only in the length direction of the outer arm by fitting. 6. A synchronous body connecting the slider and the inner arm is provided with fixing screws at both ends, and each screw is connected to the slider and the inner arm by a nut so that the length thereof can be adjusted. An excavator having an extendable bucket according to claim 1.