JPH0579063A - Back hoe - Google Patents

Abstract

PURPOSE:To improve the extent of working properties as well as to secure safety by installing a critical surface setting means, setting a critical surface on the space, and a position sensor, detecting bucket position of a back hoe unit, respectively. CONSTITUTION:In ordinary ovation at a control unit 19, a position of a bucket pin 6a is always calculated with, a vertical angle of a boom 4 (first boom 4a), a symmetrical angle of a second boom 4b and a longitudinal angle of an arm 5 by each signal out of three potentiometers 36, 37, 38 and each length of the first boom 4a, the second boom 4b and the arm 5. When the bucket pin 6a is situated on both front and lateral critical surfaces A1 and A2, as well as when a back hoe unit 3 is operated in a direction where the pin 6a separates from these front and lateral critical surfaces A1 and A2, in contrast with deceleration, each speed of respective hydraulic cylinders 11, 12, 7 is operated for speed-up in both front and lateral decelerating areas B1 and B2, so that it is put back to the original speed when having come out of these front and lateral decelerating areas B1 and B2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backhoe, and a safety structure for an operator seated in a driving part.

[0002]

2. Description of the Related Art An example of a safety structure for a driving part of a backhoe is disclosed in Japanese Patent Application Laid-Open No. 2-256722. In this structure, a dangerous surface that is separated from the outermost part of the driving section by a predetermined distance is set in the space, and a position sensor that detects the position of the bucket of the backhoe device is provided to detect this position sensor. Based on this, when the bucket tries to enter the operating unit side over the dangerous surface, the checker is provided to stop the hydraulic cylinder for driving the backhoe device and prevent the check.

[0003]

With the above configuration, when the operator of the driving section is operating the backhoe device, an operation such that the bucket is accidentally brought close to the driving section side is performed by mistake. Even if it happens, the backhoe will automatically stop when the bucket reaches a critical surface. However, in practice, the backhoe device and the bucket can be operated up to a range beyond the above-mentioned dangerous surface. Therefore, if the above-mentioned restraint means is provided, the bucket can be brought close to the operating part. Becomes impossible, and the operating range of the backhoe device and the bucket is narrowed accordingly. As a result, it becomes unavoidable to perform work such that the bucket is brought close to the driving unit to a very close distance, which causes inconvenience in terms of workability. It is an object of the present invention to ensure safety while being able to perform work such as bringing a bucket close to a driving unit to a close range.

[0004]

A feature of the present invention is that the backhoe as described above is configured as follows. That is, [1] a dangerous surface setting means for setting a dangerous surface in the space, which is separated from the outermost portion of the driving section outward by a predetermined distance, and a position sensor for detecting the position of the bucket of the backhoe device, When the bucket tries to enter the driving part side over the dangerous surface based on the detection of this position sensor, it is equipped with a check means for stopping the hydraulic cylinder for driving the backhoe device to prevent the check, and also the outermost part of the driving part. On the other hand, there is provided a changing means for moving the dangerous surface closer to and further away from the dangerous surface to change the position.

[2] A position sensor that detects the position of the bucket of the backhoe device, a storage unit that stores the position of the bucket when an artificial command is issued, and the stored positions of the bucket are connected by a plane. And a dangerous surface setting means for setting a dangerous surface in the space, which is distant from the outermost portion of the driving section, and the bucket may cross the dangerous surface and enter the driving section side based on the detection of the position sensor. In this case, there is provided a restraining means for stopping the hydraulic cylinder for driving the backhoe device and restraining the hydraulic cylinder.

[0006]

[I] With the configuration as described in [1], the backhoe device and the bucket are configured in the same manner as the conventional configuration even if the operator tries to perform an operation such that the bucket crosses over the dangerous surface and enters the driving section side. Stops on the dangerous side. And when it is necessary to work near the driving section,
Operate the changing means to bring the dangerous surface closer to the driving section. As a result, the bucket can be brought close to the driving section to perform work. In this case, since the check mechanism on the dangerous side is operating, the minimum necessary safety for preventing the situation where the bucket hits the driving section is secured. On the other hand, in the case of dangerous work in which the safety is impaired when the bucket approaches the driver's side even a little, it suffices to operate the changing means to move the dangerous surface sufficiently away from the driver's part. As a result, the bucket does not approach the operating unit side due to the action of the restraining means during the work, so that safety is surely ensured.

[II] In the case where the dangerous surface is set with the configuration as described in [2] above, in the work to be performed,
The bucket may be actually approached to each important point of the driving unit such that "this portion of the driving unit may be approached up to here", and the position of the bucket at that time (desired The position where work can be performed and required safety is ensured) is stored in the storage means. This allows
Each stored position of the bucket is connected by a surface, and a dangerous surface is set. In this way, since the dangerous surface can be set by actually approaching the bucket to the driving unit before the work, the position and shape of the dangerous surface can be freely set according to each work.

[0008]

As described above, when the restraint means based on the dangerous surface is provided, the dangerous surface can be moved closer to or away from the driving section, and the position and shape of the dangerous surface can be freely set. As a result, it becomes possible to operate the bucket up to the closest distance of the driving section according to the work,
It was possible to improve workability. Further, since the restraint means operates normally, the bucket is prevented from approaching the driving section over the dangerous surface, and the safety is secured as in the conventional configuration.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 5 shows the entire side surface of the backhoe, in which the dozer 20 and the swivel base 2 are supported by the traveling device 1 of the rubber crawler type, and the backhoe device 3 is provided in the front part of the swivel base 2. The backhoe device 3 includes a boom 4 that is vertically swung by a hydraulic cylinder 11, an arm 5 that is swung back and forth by a hydraulic cylinder 12, and a bucket 6 that is scraped and swung by a hydraulic cylinder 13. Is configured. A hydraulic motor 14 is provided for driving the swivel base 2.

The boom 4 in the backhoe device 3 is shown in FIG.
Also, as shown in FIG. 2, the second boom 4b is swingably connected around the front axis P1 of the front end of the first boom 4a that is driven to swing up and down, and the second boom 4b is connected around the front axis P2 of the second boom 4b. The support bracket 4c is swingably connected, and the arm 5 is connected to the support bracket 4c. The linkage links 8 are laid across the first boom 4a and the support bracket 4c to form a parallel four-link structure. 6 can be moved in parallel to the left and right.

As shown in FIG. 3, a control valve 21 for the hydraulic cylinder 11 of the boom 4, a control valve 25 for the hydraulic cylinder 7 of the second boom 4b of the boom 4, a control valve 22 for the hydraulic cylinder 12 of the arm 5, and a bucket 6. A control valve 23 for the hydraulic cylinder 13 and a control valve 24 for the hydraulic motor 14 of the swivel base 2 are provided. The control valves 21 to 25 are of a three-position switching type and a pilot operation type, and the flow rate can be controlled by adjusting the opening degree based on the pilot pressure. Then, pilot valves 31a, 31b, 32a, 32b, 33 of the electromagnetic proportional pressure reducing valve type that generate pilot pressure for operating the opening of each control valve 21-25 are provided.
a, 33b, 34a, 34b, 35a, 35b are provided.

As shown in FIGS. 5 and 3, the swivel base 2 is provided with a right operation lever 9 and a left operation lever 10.
The right and left operation levers 9 and 10 can be operated in the front-rear direction and the left-right direction. A potentiometer 15 for detecting the operation position of the right operation lever 9 in the front-rear direction and a potentiometer 16 for detecting the operation position in the left-right direction are provided. A potentiometer 17 for detecting the operation position of the operation lever 10 in the front-back direction and a potentiometer 18 for detecting the operation position of the left-right direction are provided. Then, operation signals from the potentiometers 15 to 18 are input to the control device 19. An operation pedal 26 is provided on the lower front side of the swivel base 2, and an operation signal from the operation pedal 26 is input to the control device 19.

With the above structure, when the right operation lever 9 is operated forward or backward, the pilot valves 31a, 3 are accordingly operated.
1b generates pilot pressure, and the control valve 21 for the boom 4
Is operated to the descending side or the ascending side, and when operated to the right or the left, the pilot valves 33a and 33b generate pilot pressure based on this, and the control valve 23 is operated to the soil discharging side or the scraping side of the bucket 6. When the left operation lever 10 is operated forward or backward, the pilot valves 32a and 32b are operated based on the operation.
Generates pilot pressure, the control valve 22 is operated to the raising side or the scraping side of the arm 5, and when operated to the right or left, the pilot valves 34a and 34b generate pilot pressure based on this and the control valve 24 turns. It is operated on the right side or the left side of the turn. When the operation pedal 26 is stepped right or left, the pilot valves 35a and 35b generate pilot pressure based on this, and the control valve 25 is operated to the right or left moving side of the second boom 4b.

In the above operation, the potentiometers 15 to 18 for the right and left operation levers 9 and 10 detect not only the operation direction of the right and left operation levers 9 and 10 but also the operation amount from the neutral position thereof. There is. As a result, as the operation amount of the right and left operation levers 9 and 10 increases, the pilot pressure of the pilot valves 31a to 34b increases and the control valve 21 increases.
The hydraulic cylinders 11 to 13 and the hydraulic motor 14 are configured to operate at higher speeds such that .about.24 are operated toward the high flow rate side, that is, the larger the right and left operating levers 9 and 10 are operated.

As shown in FIG. 5, a potentiometer 36 (corresponding to a position sensor) for detecting the vertical angle of the boom 4 (first boom 4a) and a potentiometer 37 (corresponding to a position sensor) for detecting the horizontal angle of the second boom 4b. ), And a potentiometer 38 for detecting the longitudinal angle of the arm 5
(Corresponding to a position sensor) is provided, and the detection signals from the potentiometers 36, 37, 38 are input to the control device 19.

As shown in FIGS. 2 and 5, in the swivel base 2, the backhoe device 3 is arranged on the right side, and on the left side is a driver's seat 28 and a driver unit 27 composed of the right and left operating levers 9, 10 and the like. It is arranged. A vertical partition plate 29 with a window for partitioning the backhoe device 3 and the operating unit 27 in the left-right center of the swivel base 2 (corresponding to the outermost portion of the operating unit 27).
The semi-circular upper partition plate 30 (corresponding to the outermost part of the operation unit 27) along the outside of the swivel base 2 is also fixed to the upper end of the vertical partition plate 29.

Next, the driving section 2 at a predetermined height from the ground G
7 The setting of the front dangerous surface A1 on the front side of the vertical partition plate 29 and the lateral dangerous surface A2 on the right side of the vertical partition plate 29 in the range above the predetermined position D near the lower part will be described. As shown in FIGS. 4 and 3, a changeover switch 39 and a memory button 40 are arranged in the control unit 27, and first, the changeover switch 39 is changed over to the setting mode before starting the work (step S1). As a result, the front dangerous surface A1 and the lateral dangerous surface A2 that have been set so far are erased (step S
2).

As shown in FIGS. 1 and 2, in the actual work to be performed from now on, "the bucket 6 (bucket pin 6a) may be brought close to this position with respect to this portion of the operating unit 27". Find a plurality of positions F to say. Next, operate the backhoe device 3 to move to one position F
When the bucket pin 6a is positioned at and the storage button 40 is pressed, the position F of the bucket pin 6a is stored in the control device 19 based on the detection signals from the potentiometers 36, 37 and 38 (steps S3 and S4). .. Then, the above operation is repeated for each position F shown in FIGS. 1 and 2, and each position F is stored in the control device 19 (corresponding to a storage unit).

When the storage of all positions F is completed, the changeover switch 39 is changed over to the working mode. This allows
The stored positions F are connected by a flat surface (or an arc surface that is convex outward with respect to the operating unit 27) as shown by the solid line, and the front dangerous surface A1 and the lateral dangerous surface A2 are connected to the control device 19.
Is set within (steps S5 and S6). In this case, even if the bucket pin 6a (see FIG. 1) is on the front dangerous surface A1 and the bucket 6 is operated so as to come closest to the driving unit 27 side, the locus C1 away from the driving unit 27. The tip of the bucket 6 is on the top. Further, as shown in FIG. 2, in a state where the bucket pin 6a is on the lateral dangerous surface A2, the lateral side surface of the bucket 6 is on the locus C2 separated from the vertical partition plate 29.

With respect to the front and side danger planes A1 and A2 set as described above, planes separated by a predetermined distance from the front or the right side are set, and as shown in FIGS. 1 and 2. In addition, the surface of this space and the front and side dangerous surfaces A1, A2
Meanwhile, the front deceleration region B1 and the lateral deceleration region B2 are set in the control device 19 (step S7).

When excavating the ground G by the backhoe device 3, the mechanical operating limit of the backhoe device 3 itself, which is the extent to which the backhoe device 3 can excavate the traveling device 1, can be obtained in advance. .. Then, it is calculated which locus the bucket pin 6a passes through when the operation is carried out to the operation limit, and a locus slightly (outer) than the locus of the bucket pin 6a corresponding to this operation limit is set as the boundary surface E, As shown in FIG. 1, it is set in the control device 19 in a range below the predetermined position D.

The position of the boundary surface E is moved and operated as a new boundary surface E so that the boundary surface E is smoothly connected to the front and side dangerous surfaces A1 and A2 set as described above. It is set (step S8). When the bucket 6 is operated so as to come closest to the traveling device 1 when the bucket pin 6a is on the boundary surface E, the tip of the bucket 6 passes along the locus C3 as shown in FIG.

The front and side dangerous surfaces A1, A2,
The normal work of the backhoe device 3 can be started after the setting of the front and lateral deceleration regions B1 and B2 and the boundary surface E is completed.
These are set for the swivel base 2 and move with the swivel base 2 as the swivel base 2 turns.

In the control device 19, during normal work, the vertical angle of the boom 4 (first boom 4a), the horizontal angle of the second boom 4b, and the front-back angle of the arm 5 in response to signals from the potentiometers 36, 37, 38. And the length of each of the first boom 4a, the second boom 4b, and the arm 5, the position of the bucket pin 6a is constantly calculated.

The bucket pin 6a is shown in FIGS.
When entering the front and lateral deceleration regions B1 and B2 shown in FIG. 3, the hydraulic pressure of the backhoe device 3 is operated regardless of the operation of the right and left operation levers 9 and 10 and the operation pedal 26 by operating the pilot valves 31a to 32b, 35a and 35b. Cylinders 11, 12,
The speed of 7 is decelerated. In this case, bucket pin 6
The more a moves into the front and side deceleration regions B1 and B2, that is, the closer the bucket pin 6a approaches the front and side dangerous surfaces A1 and A2, the greater the deceleration operation is performed (step S9).

When the bucket pin 6a is positioned on the front and side dangerous surfaces A1 and A2, when the backhoe device 3 is operated in a direction in which the bucket pin 6a moves away from the front and side dangerous surfaces A1 and A2, Contrary to the deceleration described above, in the front and lateral deceleration regions B1 and B2, the hydraulic cylinders 11 and 12,
The speed of 7 is increased, and the front and lateral deceleration area B
It returns to the original speed when exiting from 1, B2. On the contrary, when the bucket pin 6a tries to be operated toward the operation part 27 side beyond the front and side dangerous surfaces A1 and A2 from the front and side dangerous surfaces A1 and A2, the pilot valves 31a to 32a.
b, 35a, 35b pilot pressure disappears, control valve 2
The hydraulic cylinders 11, 12, 7 of the backhoe device 3 are stopped by 1, 22, 25 (corresponding to a restraint means).
(Step S10).

Further, the bucket pin 6a has a front and side dangerous surface A.
1 and A2, the hydraulic cylinder 13 of the bucket 6 can be operated normally. Then, the operation of moving the bucket pin 6a vertically and horizontally on the front and side dangerous surfaces A1 and A2 can be performed at an extremely low speed.

As described above, the front and lateral deceleration regions B1 and B2 are set in the portion above the predetermined position D shown in FIG. The lateral deceleration areas B1 and B2 are not set. Therefore, until the bucket pin 6a reaches the boundary surface E, the hydraulic cylinders 11, 12, 7 of the backhoe device 3 are operated at a speed based on the operation of the right and left operation levers 9, 10 and the operation pedal 26. When the bucket pin 6a is going to be operated toward the traveling apparatus 1 side beyond the boundary surface E even a little, the pilot valves 31a to 32b,
The pilot pressure of 35a, 35b disappears and the control valves 21, 2
2, 25 by the hydraulic cylinder 11 of the backhoe device 3,
12, 7 are stopped (step S10).

When the bucket pin 6a is located on the boundary surface E, the operation of the hydraulic cylinder 13 of the bucket 6 can be performed as usual, and the operation of moving the bucket pin 6a on the boundary surface E is also performed as usual. You can do it. Therefore, when the soil on the ground G near the traveling apparatus 1 is scraped off by the bucket 6, the bucket 6 may be lifted so that the bucket pin 6a moves upward on the boundary surface E. In this way, the bucket pin 6a smoothly moves from the boundary surface E to the front dangerous surface A1 and enters the front deceleration area B1, and the backhoe device 3 is decelerated as described above.

The front and side dangerous surfaces A1, A2,
When another type of work is performed after performing the work on the boundary surface E, the front and side dangerous surfaces A1 and A2 and the boundary surface E may not be adapted to this another work mode. In such a case, as shown in FIG. 4, the changeover switch 39 is switched to the setting mode to set the new front and side dangerous surfaces A1 and A2 and the boundary surface E adapted to this other work form. It's good.

[Other Embodiment] In the above-mentioned embodiment, the bucket 6 of the backhoe device 3 is operated to store the position before the work,
Although it is a format in which the arbitrary front and side dangerous surfaces A1 and A2 are set, this may be configured as follows. That is, the standard lateral dangerous surfaces A1 and A2 as shown by the solid lines in FIGS.
Is set in the control device 19 in advance. Then, by using a first dial type switch (corresponding to a changing unit) (not shown), it is possible to bring the entire position of the front dangerous surface A1 closer to the driving unit 27 side or away from the driving unit 27. Constitute. By operating a second dial type switch (corresponding to a changing unit) (not shown) also on the lateral danger surface A2, the entire position of the lateral danger surface A2 is brought closer to the driving unit 27 side, or the driving unit 27 is operated. It is configured so that it can be moved away from 27. In this case, the shapes of the standard lateral dangerous surfaces A1 and A2 serving as the reference may be arbitrarily changed.

In the above embodiment, as shown in FIG. 1, the position of the bucket pin 6a is used as a reference, but a potentiometer is installed at the position of the bucket pin 6a so that the position of the tip of the bucket 6 is set in the controller 19. Alternatively, it may be configured to constantly calculate. In this case, the loci C1 and C2 shown in FIGS. 1 and 2 are the front and side dangerous surfaces of the present invention.

It should be noted that although reference numerals are given in the claims for convenience of comparison with the drawings, the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a schematic side view of a backhoe showing a front dangerous surface, a front deceleration area, and a boundary surface.

FIG. 2 is a schematic plan view of a backhoe showing front and lateral dangerous surfaces and front and lateral deceleration areas.

FIG. 3 is a schematic circuit diagram of each hydraulic cylinder, control valve, pilot valve, right and left operating levers, changeover switch, memory button, etc. of the backhoe device.

FIG. 4 is a flowchart showing a control flow.

[Fig. 5] Overall side view of the backhoe

[Explanation of symbols]

 3 Backhoe device 6 Bucket of backhoe device 7, 11, 12 Hydraulic cylinder of backhoe device 27 Operating part 29, 30 Outermost part of operating part 36, 37, 38 Position sensor A1, A2 Dangerous surface

Claims (2)

[Claims] 1. The outermost part (29) of the operating part (27),
Dangerous surface (A
1) and (A2) are set in the space as a dangerous surface setting means,
A position sensor (36), (37), (38) for detecting the position of the bucket (6) of the backhoe device (3) is provided to detect the position sensor (36), (37), (38). Based on the bucket (6), the dangerous surface (A
1) and (A2), when trying to enter the operating part (27) side, the hydraulic cylinders (7), (11) and (12) for driving the backhoe device (3) are stopped to prevent them from being restrained. And a check means for controlling the operation part (2
A backhoe provided with a changing means for moving the dangerous surfaces (A1) and (A2) close to and away from the outermost parts (29) and (30) of 7) and changing the position thereof. 2. Bucket (6) of a backhoe device (3)
Position sensors (36), (37) for detecting the position of
(38), storage means for storing the position of the bucket (6) when an artificial command is given, and each position of the stored bucket (6) are connected by a plane, and the operating unit ( Two
7) is provided with a danger surface setting means for setting the danger surfaces (A1) and (A2) outwardly separated from the outermost parts (29) and (30) in the space, and the position sensor (36),
The bucket (6) based on the detection of (37) and (38)
Goes over the dangerous surfaces (A1), (A2) and the driving section (2
When trying to enter the 7) side, hydraulic cylinders (7), (11), (1) for driving the backhoe device (3).
A backhoe provided with a restraining means for stopping 2) and restraining this.