JPH1121935A - Backhoe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a contact between the outer frame of a driver's seat and a moving bucket by obstructing entering by a horizontal second restraining surface when the bucket is brought near towards a driving section while having a sideways moving component. SOLUTION: When a bucket 6 is brought near towards a driving section while having a sideways moving component, the entering of the bucket 6 from a horizontal second restraining surface A3 at a place separate from the driving section is prevented because stop delay by the inertia of the bucket 6 must be considered. When the bucket 6 has no sideways moving component, on the other hand, entering into a region formed between the horizontal second restraining surface A3 and a horizontal first restraining surface A2 while crossing the horizontal second restraining surface A3 is permitted, and the bucket is controlled so as to be hindered when the bucket crosses the horizontal first restraining surface A2. Accordingly, even when the bucket is shifted from the front of the driving section to the side, the bucket traces a shorter path and can be moved, excavation works in a section brought near to the driving section are conducted, and housing, in which the bucket is brought near to the side of the driving section, can also be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for preventing a backhoe from coming into contact with an outer frame covering an operating portion and a bucket of the backhoe device.

[0002]

2. Description of the Related Art In a backhoe, in order to avoid contact between an outer frame covering an operating portion and a bucket, a front restraint surface is provided at a predetermined distance in front of the outer frame covering the operating portion, and a lateral sideways sideways. A check surface was provided. When the reference portion of the bucket moving closer to the driving unit from the lateral outside reaches the lateral restraint surface, a stop command is issued, but in consideration of the stop delay due to the inertia of the bucket, the lateral restraint surface is It is provided at a distance from the external frame.

[0003]

In the conventional structure as described above, as shown in FIG. 6, even when the bucket moves away from the driving section, the front check surface A
When the reference portion of the bucket hangs over the area where the driving section is located beyond the area 1 and the lateral restraint surface A2, the operation of the bucket is stopped. Then, as shown by an arrow in FIG. 6, when moving from the front of the driving unit to the lateral side of the driving unit, the bucket is sharpened at the corner where the front restraint surface A1 intersects with the first lateral restraint surface A2. Can be moved
Although the quick movement can be performed, the bucket stops when the reference portion of the bucket reaches the above-mentioned area, so that the movement of the bucket cannot be performed smoothly. On the other hand, when the bucket is driven along the lateral side of the driving unit, the bucket does not approach the driving unit, so that it is not necessary to set the position of the lateral restraint surface to a position considering inertia.

[0004] It is an object of the present invention to provide an apparatus in which an external frame of an operating unit does not come into contact with a moving bucket while the bucket can be moved smoothly.

[0005]

[Means for Solving the Problems]

[Structure] A characteristic structure of the invention according to claim 1 includes a position sensor for detecting a position of a bucket, a control unit for controlling the operation of the bucket based on the detection of the position sensor, and an external unit for covering an operation unit. A front restraint surface for preventing the bucket from entering at a spatial position separated by a predetermined distance from the frame; and a lateral one restraining surface for preventing the bucket from entering a spatial position at a predetermined distance from the external frame laterally outward of the driving unit. Assuming that the second lateral restraint surface is further laterally outward of the first lateral restraint surface, and the control means causes the bucket to approach the driving unit with a lateral movement component, The second lateral restraint surface is designed to prevent entry, and the operation and effect are as follows.

[Operation] In other words, when the bucket approaches the driving section with a laterally moving component, it is necessary to consider the stop delay due to the inertia of the bucket. Therefore, the second lateral restraint surface located at a position distant from the driving section. This prevents the bucket from entering more. On the other hand, if the bucket does not have a lateral movement component, that is, if the bucket is squeezed along the driving unit, or if it has a lateral movement component, but moves away from the driving unit, The control is made so that it is allowed to enter the region formed between the second lateral restraint surface and the first lateral restraint surface, and to block the area beyond the first lateral restraint surface.

[Effect] With this, even when the bucket is moved laterally from the front of the driving unit, the bucket can be moved by following a shorter path, and excavation work can be performed in a portion close to the driving unit. At the same time, it is possible to perform storage close to the lateral side of the driving unit.

According to a second aspect of the present invention, in the first aspect of the present invention, a third lateral restraint surface is further provided laterally outside the first lateral restraint surface. In the area between the first check surface and the third lateral check surface,
The control means is configured to reduce the moving speed of the bucket, and is configured to form a deceleration area outside the second lateral restraint surface when the bucket is prevented from entering by the second lateral restraint surface. The operation and effect are as follows.

[Effects] That is, the moving speed of the bucket is reduced between the first lateral restraint surface for preventing the bucket from entering and the third lateral restraint surface located outside the first restraint surface, and the bucket is gently stopped. When the bucket is stopped at the second lateral restraint surface, a deceleration area is provided outside the second lateral restraint surface, and the lateral restraint surface is provided between the first and second restraint surfaces. Even if it is replaced, it can be stopped gently.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an overall side view of a backhoe. A swivel 2 is supported on a traveling device 1 of the rubber crawler type, and a backhoe 3 is provided in front of the swivel 2. The backhoe device 3 includes a boom 4 that is vertically oscillated by a hydraulic cylinder 11, an arm 5 that is oscillated back and forth by a hydraulic cylinder 12, and a bucket 6 that is oscillated by a hydraulic cylinder 13. ing.

The boom 4 of the backhoe device 3 includes a first boom portion 4a which is vertically swung and a first boom portion 4a.
The second boom portion 4b is swingably connected around the axis P1 at the front end of the second boom, and the support bracket 4c is swingably connected around the axis P2 at the front end of the second boom portion 4b. The arm 5 is connected to the support bracket 4c. An interlocking link 8 is laid across the first boom portion 4a and the support bracket 4c to form a parallel quadruple link, and the hydraulic cylinder 7 swings the second boom portion 4b to move the arm 5 and the A so-called offset operation is performed in which the bucket 6 is moved left and right in parallel.

As shown in FIGS. 1 and 5, in the swivel base 2, a backhoe device 3 is disposed on the right side, and a driver's seat 14 and an operation unit 15 including right and left operation levers 9, 10 and the like are disposed on the left side. Have been. At the left and right center of the swivel base 2, a vertical partition plate 16 with a window is provided to partition the backhoe device 3 and the operation unit 15, and an upper partition plate 17 along the outside of the swivel base 2 is provided at the upper end of the vertical partition plate 16. Has been fixed.

Next, the operation structure of the hydraulic circuit structure, the backhoe device 3, the swivel 2 and the like will be described. As shown in FIG. 2, the control valve 21 of the hydraulic cylinder 11 of the first boom portion 4a (boom 4), the control valve 22 of the hydraulic cylinder 12 of the arm 5, the control valve 23 of the hydraulic cylinder 13 of the bucket 6,
The control valve 24 of the swivel motor 18 of the swivel 2, the control valve 25 of the hydraulic cylinder 7 of the second boom part 4 b, the right traveling device 1
, A control valve 27 of the left traveling device 1, a control valve 28 of a service port (not shown), and a control valve 29 of a hydraulic cylinder 51 for raising and lowering the dozer 19 shown in FIG.
Is provided, and hydraulic oil from the pump 20 is supplied to the control valve 2.
1 to 29.

The control valve 21 of the first boom part 4a, the control valve 22 of the arm 5, the control valve 23 of the bucket 6, the control valve 24 of the swivel 2 and the control valve 25 of the second boom part 4b It is an operation type and a neutral return type. The control valves 26 and 27 of the right and left traveling devices 1, the control valve 28 of the service port, and the control valve 29 of the dozer 19 are mechanically operated and neutral return type operated by operation levers (not shown).

As shown in FIG. 3, the right operating lever 9 is configured to be operable in the front, rear, left and right directions, and a pilot valve 31a for generating a pilot pressure by a rear operation of the right operating lever 9;
A pilot valve 31b that generates pilot pressure by operating the right operating lever 9 in front, a pilot valve 33a that generates pilot pressure by operating the right operating lever 9 to the right, and a pilot that generates pilot pressure by operating the right operating lever 9 to the left. A valve 33b is provided.

Similarly, the left operation lever 10 is also configured to be operable in the front, rear, left and right directions. The pilot valve 32a generates a pilot pressure by the rear operation of the left operation lever 10, and the pilot pressure is generated by the front operation of the left operation lever 10. A pilot valve 32b which generates a pilot pressure by operating the left operating lever 10 to the right, and a pilot valve 34b which generates pilot pressure by operating the left operating lever 10 to the left are provided.

As shown in FIG. 3, there is provided an operation pedal 39 which can be freely operated to the left and right, and a pilot valve 35 which generates a pilot pressure by operating the operation pedal 39 to the left.
a, and a pilot valve 35b for generating a pilot pressure by operating the operation pedal 39 to the right. A pilot pump 30 for supplying pilot pressure to the pilot valves 31a to 35b is provided.

As shown in FIGS. 2 and 3, the pilot valves 31a and 31b of the right operating lever 9 and the first boom portion 4a
Control valve 21, the pilot valve 33a of the right operation lever 9,
The control valve 33b and the control valve 23 of the bucket 6 are connected via a pilot oil passage, and the pilot valves 32a and 32b of the left operation lever 10, the control valve 22 of the arm 5, and the pilot valves 34a and 34b of the left operation lever 10 are connected. And the control valve 24 of the swivel 2 are connected via a pilot oil passage. The pilot valves 35a and 35b of the operation pedal 39 and the control valve 25 of the second boom portion 4b are connected via a pilot oil passage.

When the right operating lever 9 is operated backward by the above structure, the pilot pressure from the pilot valve 31a causes
When the control valve 21 is operated on the ascending side of the first boom portion 4a (extending side of the hydraulic cylinder 11) and the right operating lever 9 is operated in advance, the pilot pressure from the pilot valve 31b causes
The control valve 21 is operated on the lowering side of the first boom portion 4a (the contracting side of the hydraulic cylinder 11). When the right operation lever 9 is operated to the right, the control valve 23 is driven by the pilot pressure from the pilot valve 33a to discharge the bucket 6 to the discharging side (the hydraulic cylinder 1).
When the right operating lever 9 is operated to the left and the right operating lever 9 is operated to the left, the control valve 23 is operated to the rake side of the bucket 6 (the extending side of the hydraulic cylinder 13) by the pilot pressure from the pilot valve 33b.

When the left operating lever 10 is operated backward, the control valve 22 is operated to the squeezing side of the arm 5 (extending side of the hydraulic cylinder 12) by the pilot pressure from the pilot valve 32a, and when the left operating lever 10 is operated forward. The control valve 22 is operated to the discharging side of the arm 5 (the contracting side of the hydraulic cylinder 12) by the pilot pressure from the pilot valve 32b. When the left operating lever 10 is operated to the right, the pilot valve 34
When the control valve 24 is operated to the right turning side of the swivel base 2 by the pilot pressure from a and the left operating lever 10 is operated to the left, the control valve 24 is swiveled counterclockwise by the pilot pressure from the pilot valve 34b. It is operated on the side.

When the operation pedal 39 is depressed to the left, the control valve 25 of the second boom portion 4b is operated to the left swing side (extension side of the hydraulic cylinder 7) by the pilot pressure from the pilot valve 35a. When the right stepping operation is performed, the control valve 25 of the second boom portion 4b is operated to the right swing side (the contraction side of the hydraulic cylinder 7) by the pilot pressure from the pilot valve 35b.

As the right and left operation levers 9 and 10 and the operation pedal 39 are largely operated from the neutral position, the pilot valve 3
The pilot pressures 1a to 35b are configured to increase. Thereby, the right and left operation levers 9, 10,
The larger the operation pedal 39 is operated from the neutral position, the larger the pilot pressure of the pilot valves 31a to 35b, and the more the control valves 21 to 25 are operated to the larger flow rate side. That is, as the right and left operation levers 9 and 10 and the operation pedal 39 are operated larger, the hydraulic cylinders 7, 11, 12, and 13 and the turning motor 18 operate at a higher speed.

Next, the front restraint surface A1, the first lateral restraint surface A2, the second transverse restraint surface A3, and the like set for the swivel 2 will be described. As shown in FIGS. 4 and 5, the vertical partition 1
6, a front restraint surface A1 that is separated by a predetermined distance forward from the front edge of the upper partition plate 17 and the front edge of the upper partition plate 17, and a first horizontal restraint surface that is separated by a predetermined distance to the right from the lateral side of the vertical partition plate 16 A2 and further outwardly the second lateral restraint surface A3 are assumed and set in the control device 40 (see FIG. 3) as control means. Here, the vertical partition plate 16 and the upper partition plate 17 are referred to as an external frame.

In this case, when the bucket pin 6a connecting the bucket 6 to the tip of the arm 5 is located on the front restraint surface A1, the bucket 6 is swung so as to be closest to the driving unit 15 side. Also, the front restraint surface A is positioned so that the tip of the bucket 6 is located on a locus C1 separated by a predetermined distance from the front edge of the vertical partition 16 and the front edge of the upper partition 17.
1 is set. In a state where the bucket pin 6a is located on the first horizontal braking surface A2, the first horizontal braking surface A2 is set so that the left lateral surface of the bucket 6 is located on a locus C2 separated from the vertical partition plate 16 by a predetermined distance. ing.

A plane which is separated from the front and first lateral restraint surfaces A1 and A2 by a predetermined distance to the front or right is set, and the space between the space and the front and first lateral restraint surfaces A1 and A2 is frontward. The control device 40 is set as the restraint area B1 and the first lateral restraint area B2. The outer side surface of the lateral restraint region B2 is referred to as a second lateral restraint surface A3. Further, a third lateral restraint surface is provided further outside the second lateral restraint surface A3, and the second transverse restraint surface A3 and the third lateral restraint surface are provided.
A second lateral restraint region B3 is provided between the vehicle and the restraint surface. The front and side first and second check surfaces A1, A2, A3 as described above,
The front and lateral restraint areas B1, B2, and B3 are set for the swivel 2 and move with the swivel 2 as the swivel 2 turns.

As shown in FIGS. 1 and 4, a connecting portion between the swivel base 2 and the first boom portion 4a has a first
Angle sensor 36 for detecting the vertical angle of boom portion 4a
Is provided at a connection portion between the first and second boom portions 4a and 4b, and the second boom portion 4b with respect to the first boom portion 4a is provided.
Is provided with an angle sensor 37 for detecting the left-right angle of the camera. The connecting portion between the support bracket 4c and the arm 5 has a second
An angle sensor 38 for detecting the front-rear angle of the arm 5 with respect to the boom portion 4b is provided. Here, the angle sensors 36, 37, and 38 are referred to as position sensors.

The angle sensors 36, 37, 3 as described above
8 is input to the control device 40, and based on the detection values of the angle sensors 36, 37, and 38, as described later, the front and first and second lateral restraint surfaces A1, A2, A3, The control device 40 detects the position of the bucket pin 6a with respect to the lateral restraint regions B1 and B2.

As shown in FIG. 3, a pilot oil passage connecting the pilot valve 31a of the right operating lever 9 and the control valve 21 of the first boom portion 4a (operating the control valve 21 of the first boom portion 4a upward). Pilot oil passage), a pilot oil passage connecting the pilot valve 32a of the left operating lever 10 and the control valve 22 of the arm 5 (a pilot oil passage for operating the control valve 22 of the arm 5 to the scraping side), and an operation pedal. Each of the pilot oil passages (the pilot oil passages for operating the control valve 25 of the second boom portion 4b to the left oscillating side) connecting the pilot valve 35a of FIG. -Type pressure control valves 41, 42, 4
3 are provided.

Therefore, the pilot pressure is reduced by the pressure control valves 41, 42 and 43 (the maximum pressure is the value set by the right and left operating levers 9 and 10 and the operating pedal 39), and the right and left operating levers are reduced. 9, 10, regardless of the operation position of the operation pedal 39, the control valve 21 of the first boom portion 4a
Of the control valve 22 of the arm 5, the opening of the control valve 25 of the second boom portion 4b on the left swing side can be arbitrarily changed. By setting the pilot pressure to zero by the pressure control valves 41, 42, 43, the hydraulic cylinder 11, the arm 5 and the arm 5 of the first boom portion 4a can be operated regardless of the operation positions of the right and left operation levers 9, 10 and the operation pedal 39. The hydraulic cylinder 12 of the second boom portion 4b can be stopped.

Next, the relationship between the backhoe device 3 and the restraint areas B1, B2, B3 will be described. In this case, the position of the bucket 6 is a problem. However, the control is performed by using the bucket pin 6 a as the reference position of the bucket 6. As shown in FIG.
, The vertical angle of the first boom portion 4a, the left / right angle of the second boom portion 4b, the front / rear angle of the arm 5 based on the detection values of the angle sensors 36, 37, and 38;
a, the position of the bucket pin 6a is always detected based on the lengths of the second boom portion 4b and the arm 5. Therefore, based on the detection result, the bucket pin 6a
It is determined in which area the position is located. In the front restraint area B1, the lateral restraint areas B2 and B3, and in the other areas located outside the both restraint areas B1, B2 and B3. The control corresponding to each case and the certain case, that is, the front restraint control when the vehicle is in the front restraint region B1, the lateral restraint control when the vehicle is in the lateral restraint regions B2 and B3, and the normal control when the vehicle is in another region. (S100 to S1
03).

As shown in FIG. 6, in the normal control,
Based on the operation of the left and right operation levers 10 and 9 and the operation pedal 39, if there is a command to move the first boom part 4a up and down, the boom is moved up and down, and the arm 5 is moved back and forth, that is, it is scraped with the earth discharging side. When an operation command is issued to the retracted side, the arm 5 is moved back and forth, and when an operation command is issued to swing the second boom portion 4b left and right, the second boom portion 4b and the arm 5 are swung left and right as a unit. A so-called offset operation is performed (S201 to S206). In this control, the moving speed of the first boom portion 4a and the like is set so as not to be reduced. When the position of the bucket pin 6a reaches the second lateral restraint surface A3 of the lateral restraint area B2 in the state where the normal control is being performed, a left swing command is issued to the boom, that is, the second boom portion 4b. In this case, the swing operation to the left is stopped (S
207-S209). In other words, the presence of the left swing command means that the bucket 6 at least enters the driving unit 15, and in this case, the bucket 6
In consideration of the inertia of the vehicle, the stop operation is performed on the outer lateral second restraint surface A3. Therefore, when moving in a direction away from the driving unit 15 by a swing command to the right, normal control is performed.

The front restraint control will be described. First, an operation when an operation command is issued to the backhoe device 3 will be described. That is, when a vertical movement command is issued to the boom 4, the following control is performed. When the vehicle enters the front restraint area B1 shown in FIG. 10, the right operation lever 9 is operated backward to raise the first boom portion 4a, and the bucket pin 6a
Is handled before reaching the front restraint surface A1 as follows. The specific operation mode in this case is that the pilot pressure of the pilot valve 31a is reduced by the pressure control valve 41 shown in FIG. 3, and the first boom portion 4a is operated regardless of the operation position of the rear operation of the right operation lever 9. The ascending speed (extension speed of the hydraulic cylinder 11) is decelerated, and as the bucket pin 6a approaches the front restraint surface A1, the ascending speed of the first boom portion 4a (extension speed of the hydraulic cylinder 11) is greatly reduced. Operated (S301, 302, 30
5). The case where the bucket pin 6a has reached the front restraint surface A1 (S303, 304) will be described later.

Conversely, when the right operating lever 9 is operated forward to lower the first boom portion 4a, the bucket pin 6a is separated from the front restraint surface A1.
Even if a is located in the front restraint plane A1 and the front restraint area B1, the first boom portion 4a is operated to descend at a speed corresponding to the operation position of the previous operation of the right operation lever 9 regardless of this (S306). (As shown in FIG. 3, the pressure control valve 4 is provided in the pilot oil passage of the pilot valve 31b of the right operation lever 9.
1 is not provided).

When a vertical movement command is issued to the boom 4 in the front restraint area B1, the following control is performed.
In a state where the bucket pin 6a has entered the front restraint area B1 (S307), when the left operating lever 10 is operated backward to squeeze the arm 5, the bucket pin 6a is brought into a state of approaching the front restraint surface A1 (S308). ). In this state, the pilot pressure of the pilot valve 32a is reduced by the pressure control valve 42 shown in FIG.
0, the scraping speed of the arm 5 (the extension speed of the hydraulic cylinder 12) is decelerated regardless of the operation position of the post-operation. The more the bucket pin 6a approaches the front restraint surface A1, the more the arm 5 is scraped. The depressing speed (extension speed of the hydraulic cylinder 12) is greatly reduced (S308, S31).
0). When the bucket pin 6a reaches the front restraint surface A1 (S
308), the pilot pressure of the pilot valve 32a is set to zero by the pressure control valve 42 shown in FIG. 3, the control valve 22 is operated to the neutral position irrespective of the rear operation position of the left operation lever 10, and the arm 5 (Hydraulic cylinder 12) stops (S309).

Conversely, when the left operation lever 10 is operated forward and the arm 5 is operated to the earth discharging side (S307), the bucket pin 6a is separated from the front restraint surface A1, and the bucket pin 6a is moved forward. Even when the arm 5 is located in the plane A1 and the front restraint area B1, the arm 5 is operated to the earth discharging side at a speed corresponding to the operation position of the front operation of the left operation lever 10 regardless of this (S311) (FIG. 3). Left operating lever 1 as shown
This is because the pressure control valve 42 is not provided in the pilot oil passage of the zero pilot valve 32b).

When the bucket pin 6a enters the front restraint area B1, the operation pedal 39 is depressed to swing the second boom portion 4b, and the bucket pin 6a approaches the front restraint surface A1. (S315). In this state, the pilot pressure of the pilot valve 35a is reduced by the pressure control valve 43 shown in FIG. 3, and the left swing speed of the second boom portion 4a (regardless of the operation position of the left pedal operation of the operation pedal 39) ( Extension speed of hydraulic cylinder 7)
Is decelerated, and as the bucket pin 6a approaches the front restraint surface A1, the left swing speed (extension speed of the hydraulic cylinder 7) of the second boom portion 4a is increased and reduced (S317). When the bucket pin 6a reaches the front restraint surface A1 (S313), the pilot pressure of the pilot valve 35a is set to zero by the pressure control valve 43 shown in FIG.
The control valve 25 is operated to the neutral position irrespective of the operation position of the left pedal operation of the operation pedal 39, and the second boom portion 4b (the hydraulic cylinder 7) stops (S314).

Conversely, when the operation pedal 39 is depressed to swing the second boom portion 4b toward the opposite side (S31).
5) Since the bucket pin 6a is separated from the front restraint surface A1, even if the bucket pin 6a is located in the front restraint surface A1 and the front restraint area B1, the depression operation of the operation pedal 39 is performed regardless of this. At the speed corresponding to the operating position, the second
The boom portion 4b is rocked (S316) (due to the point that the pressure control valve 43 is not provided in the pilot oil passage of the pilot valve 35b of the operation pedal 39 as shown in FIG. 3).

Next, when the bucket pin 6a reaches the front restraint surface A1 by the raising operation of the first boom portion 4a (S3
02) and the case where the bucket pin 6a reaches the front restraint surface A1 by the scraping operation of the arm 5 will be described.
As shown in FIG. 3, an electromagnetically operated switching valve 44 is provided in a pilot oil passage between the pressure control valve 41 (the pilot valve 31a of the right operation lever 9) and the control valve 21. The switching valve 44 has a first position 44a and a second position 44b. In the first position 44a, the pilot pressure of the pilot valve 31a is supplied only to the control valve 21 and the second position 4a.
4b, the pilot pressure of the pilot valve 31a is supplied to the pilot oil passage between the pilot valve 32b of the left operation lever 10 and the control valve 22 via the control valve 21 and the pilot oil passage 45. , Is normally operated to the first position 44a.

For example, the right operation lever 9 is operated backward to
When the raising operation of the boom portion 4a is to be performed, the switching valve 44 shown in FIG. 3 is operated from the first position 44a to the second position 44b, and at the same time, the pressure control valve 41 slightly raises the pilot pressure from zero. Operated.

Thus, the pilot pressure of the pilot valve 31a of the right operation lever 9 is supplied to the control valve 21 (upward side) of the first boom portion 4a, and at the same time, the control valve 22 of the arm 5 (upward discharge side). ), The first boom portion 4a is raised at the lowest speed (the hydraulic cylinder 1).
1 is extended at the lowest speed) (S303), and at the same time, the arm 5 is slowly operated to the discharging side (the hydraulic cylinder 12 contracts slowly) (S304).

When the above operation is performed, the first boom portion 4a is raised and the angle D between the second boom portion 4a and the arm 5 is gradually increased as shown in FIG. And the bucket pin 6a rises along the front restraint surface A1 (while detecting the position of the bucket pin 6a based on the detection values of the angle sensors 36, 37, and 38, etc.). The pilot pressure is controlled by the pressure control valve 41 so that the bucket pin 6a is always located on the front restraint surface A1). At the same time, when the right operating lever 9 is operated to the left to rake the bucket 6,
The bucket 6 can be kept horizontal.

Next, the lateral restraint control will be described. In this lateral restraint control, the control mode when the bucket pin 6a is located in the first lateral restraint area B2 and the second lateral restraint area B3 is almost the same, so that the bucket pin 6a is located in the first lateral restraint area B2. Mainly in the horizontal second restraint area B3.
, Only the different points will be described.

The control from the state where the position of the bucket pin 6a is located in the first lateral restraint area B2 will be described. First, there is a problem whether an offset operation instruction is issued and whether the instruction indicates leftward swing (S401). Depress the operation pedal 39 to the left to
When the boom portion 4b is swung to the left, the bucket pin 6a
Comes closer to the first lateral restraint surface A2 (S40).
4). In this state, the pilot pressure of the pilot valve 35a is reduced by the pressure control valve 43 shown in FIG. 3, and the left swing speed of the second boom portion 4b (regardless of the operation position of the left pedal operation of the operation pedal 39). Hydraulic cylinder 7
Is decelerated (S404).
As the bucket pin 6a approaches the lateral restraint surface A2, the second
The left swing speed (extension speed of the hydraulic cylinder 7) of the boom portion 4b is greatly reduced. When the bucket pin 6a reaches the first lateral braking surface A2, the pilot pressure of the pilot valve 35a is set to zero by the pressure control valve 43 shown in FIG. The valve 25 is operated to the neutral position and the second boom portion 4b
(Hydraulic cylinder 7) stops (S403).

Conversely, when the operation pedal 39 is depressed to the right and the second boom portion 4b is pivoted to the right, the bucket pin 6
a is separated from the first lateral restraint surface A2, so that even if the bucket pin 6a is located in the first lateral restraint surface A2 and the first lateral restraint area B2, the operation pedal 39 is not related to this.
The second boom portion 4b is swung to the right at a speed corresponding to the operation position of the right depressing operation (the pilot oil passage of the pilot valve 35b of the operation pedal 39 as shown in FIG. 3).
(Because the pressure control valve 43 is not provided) (S40)
5).

In the state where the bucket pin 6a has entered the first lateral restraint area B2, the bucket 5 can be raised or lowered by operating the first boom portion 4a or by operating the arm 5 to the scraping side or the earth discharging side. Since the pin 6a does not approach the lateral first restraining surface A2, the first boom portion 4a is raised and lowered, and the arm 5 is squeezed when the bucket pin 6a enters the first lateral restraining region B2. The operation to the side and the earth discharging side can be freely performed (S406).
To S409). The bucket pin 6a is located in the second lateral restraint area B3.
In this case, the control shown in the other steps can be used as it is simply by switching the first lateral restraint surface A2 to be determined in step S402 to the second lateral restraint surface A3.

[Another Embodiment of the Invention] (1) In the above embodiment, in the lateral restraint control, when the bucket pin 6a is located in the first lateral restraint area B2, the left side of the second boom portion 4b is left. When a swing command, that is, an offset command is issued, the motor decelerates (S40).
4) Although the control mode has been described, it may be controlled so as to stop the leftward swing motion approaching the driving unit 15 as shown in step 403.

(2) In the embodiment of the present invention, FIG.
As shown in FIG. 5, the front and side restraint surfaces A1, A2, and A3 are set based on the position of the bucket pin 6a, but an angle sensor (not shown) is also provided at the position of the bucket pin 6a. The front and lateral restraint surfaces A1 and A2 may be set with respect to the position of the tip of the bucket 6. In this case, the trajectories C1 and C2 shown in FIG. 5 are the front and lateral restraint surfaces of the present invention.

(3) The operating positions of the right and left operating levers 9, 10 and the operating pedal 39 are electrically detected by a potentiometer (not shown), and a pilot valve (not shown) of the electromagnetic proportional pressure reducing valve type is operated. And the pilot control valve 2
1 to 25 operating type, right and left operating levers 9, 1
The present invention is also applicable to a type in which an operation position of the operation pedal 39 is electrically detected by a potentiometer (not shown) and a control valve (not shown) of an electromagnetic proportional pressure reducing valve type is operated based on the detected value. Is applicable. Further, the present invention can be applied to a backhoe in which the driving unit 15 is arranged on the right side of the swivel base 2 and the boom 4 (first boom portion 4a) of the backhoe device 3 is arranged on the left side of the swivel base 2.

(4) In the above embodiment, the first horizontal
Although the outer side surface of the restraining area B2 is the second horizontal restraining surface A3, the outer side surface of the second horizontal restraining surface A3 and the outer surface of the first horizontal restraining area B2 may be configured separately. In this case, the outer side surface of the first lateral restraint region B2 becomes the third lateral restraint surface. With such a configuration, it is possible to expand a range of control options such as making the surfaces A2 and A3 match the driving feeling of the operator.

[Brief description of the drawings]

FIG. 1 is an overall side view of a backhoe.

FIG. 2 is a hydraulic circuit diagram showing a hydraulic cylinder, a control valve, and the like of the backhoe device.

FIG. 3 is a hydraulic circuit diagram showing right and left operation levers, operation pedals, pilot valves, pilot oil passages, and the like.

FIG. 4 is a side view showing a front restraint surface and a front restraint area.

FIG. 5 is a plan view showing front and side restraint surfaces and front and side restraint areas.

FIG. 6 is a plan view showing a state where the bucket enters the lateral restraint region from the front.

FIG. 7 is a plan view showing a state where the bucket enters the lateral restraint region from the side.

FIG. 8 is an overall control flowchart.

FIG. 9 is a normal control flowchart.

FIG. 10 is a flowchart showing the first half of the control flow in the front restraint surface and the front restraint area.

FIG. 11 is a flowchart showing the latter half of the control flow in the front restraint surface and the front restraint area.

FIG. 12 is a flowchart showing lateral restraint control.

[Explanation of symbols]

 6 Bucket 15 Operating unit 16, 17 External frame 36, 37, 38 Position sensor 40 Control means A1, A2, A3 Checking surface

Claims (2)

[Claims] 1. A spatial position which is provided with a position sensor for detecting a position of a bucket, and a control means for controlling the operation of the bucket based on the detection of the position sensor, and is provided at a predetermined distance from an external frame covering the driving unit. In addition, it is assumed that a front restraint surface for preventing the entry of the bucket and a lateral one restraint surface for preventing the bucket from entering at a spatial position laterally outward of the driving unit at a predetermined distance from the external frame are assumed. Assuming a horizontal second restraint surface further laterally outward of the surface, if the bucket approaches the driving section with a lateral movement component by the control means, the entry is prevented by the second horizontal restraint surface A backhoe configured to do so. 2. A lateral third restraint surface is further provided laterally outside of the lateral first restraint surface, and in a region between the lateral first restraint surface and the lateral third restraint surface, the control means controls the bucket. The moving speed is reduced, and the second
2. The backhoe according to claim 1, wherein a deceleration region is formed outside the second lateral restraint surface when the bucket is prevented from entering by the restraint surface.