JP2002206251A - Backhoe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a backhoe with interference prevention control or a crane function, which is provided with an interference prevention control means for restraining and controlling the operation of a front device according to the detection of the attitude of the front device in order to inhibit the intrusion of a bucket into an operation part, and enables the favorable use of overturning prevention control for the backhoe even during a change in the specifications of the front device. SOLUTION: Parameters for calculating the bucket position of the front device 8 are stored in a rewritable storage means and constituted so that the arbitrary parameter can be read out and used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backhoe having interference prevention control means for restraining the operation of the front device based on the attitude detection of the front device so as to prevent the bucket from entering the driving section, or The present invention relates to a backhoe with a crane function, comprising: means for detecting a posture of a front device and calculating a horizontal position of a load hanging point at a front device front end, and means for calculating a load acting on the load hanging point. .

[0002]

2. Description of the Related Art In a backhoe provided with the above-described interference prevention control means, parameters such as a distance between fulcrums of a front device are previously input to a controller. The position of the bucket is calculated based on this.

[0003] In a backhoe with a crane function, parameters such as the distance between fulcrum points in the front device, the weight and the position of the center of gravity of each member constituting the front device, and the like are input to a controller in advance, and the load is suspended from these. The horizontal position of the point is calculated and displayed as the suspension radius, or the rated suspension load in this case is displayed.

[0004]

In the above-mentioned backhoe with interference prevention control means or crane function, the front device is designed so that arms of different lengths are replaced or buckets of different capacities are replaced. If used after being changed, the actual data does not coincide with the data of the parameters input in advance, and proper control cannot be performed.

The present invention has been made in view of such a point, and even if the specifications of the front apparatus are changed, the interference prevention control or the backhoe fall control with a crane function is preferably used. The primary purpose is to be able to

[0006]

Means for Solving the Problems [Configuration, Function and Effect of the Invention According to Claim 1]

(Structure) The invention according to claim 1 is provided with interference prevention control means for restraining the operation of the front device based on the attitude detection of the front device so as to prevent the bucket from entering the driving section. In the backhoe, parameters for determining a bucket position in the front device are stored in rewritable storage means, and arbitrary parameters can be read and used.

(Operation) According to the above configuration, for example, when the arm of the front device is replaced with one having a different length or the bucket is replaced with one having a different size (capacity), the arm is stored and stored. By reading and setting an appropriate one of the parameters, it is possible to execute the interference prevention control corresponding to the front device whose specification has been changed.

Here, a plurality of types of stored parameters are stored and stored in advance in the manufacturing process, and parameters corresponding to the specifications of the front device at that time are read out and set at the time of shipment from the factory. Become. Also, when the user changes the specifications of the front device, the parameters corresponding to the specifications can be read and set. Also, when using special specifications,
Parameters can be rewritten and changed.

(Effect) Therefore, according to the first aspect of the present invention, it is not necessary to develop a controller for each model having different specifications, and it is possible to accurately perform desired interference prevention control with an inexpensive configuration. Become. In addition, it is possible to easily cope with a specification change on the user side, which is excellent in usability.

[Structure, operation and effect of the invention according to claim 2]

(Structure) The invention according to claim 2 is means for detecting the attitude of the front device, calculating the horizontal position of the load suspension point at the front end of the front device, and calculating the load acting on the load suspension point. In a backhoe with a crane function having means for calculating, a parameter for calculating the position of the load suspension point in the front device is stored in rewritable storage means, and arbitrary parameters can be read and used. There is a feature.

(Operation) According to the above configuration, for example, when the arm or the boom in the front device is replaced with one having a different length, the corresponding one of the stored parameters is read and set. Thereby, it is possible to calculate the suspension radius and suspension load corresponding to the front device whose specification has been changed.

Here, a plurality of types of stored parameters are stored and stored in advance in the manufacturing process, and parameters corresponding to the specifications of the front device at that time are read out and set at the time of factory shipment. Become. Also, when the user changes the specifications of the front device, the parameters corresponding to the specifications can be read and set. Also, when using special specifications,
Parameters can be rewritten and changed.

(Effect) Therefore, according to the second aspect of the present invention, it is not necessary to develop a controller for each model having different specifications, and a desired crane function can be exhibited with an inexpensive configuration. In addition, it is possible to easily cope with a specification change on the user side, which is excellent in usability.

[Structure, operation and effect of the invention according to claim 3]

(Structure) The invention according to claim 3 is the invention according to claim 2, further comprising a pressure sensor for detecting a negative pressure of the boom cylinder in the front device, and a suspension load based on the detected load pressure. Is calculated.

(Operation) According to the above configuration, the suspension load is calculated based on the detection of the front attitude and the negative pressure of the boom cylinder, and the suspension load is displayed, and an alarm is issued when the computed suspension load approaches the rated load. Or you can.

(Effects) Therefore, according to the third aspect of the present invention, it is possible to calculate the overturning moment acting on the body without equipping the load suspension point with a load sensor or the like. There is no need to provide a long electric wire between the load sensor and the body, and the possibility of causing a disconnection trouble or the like is reduced, and reliability can be improved.

[0020]

FIG. 1 shows an overall side view of a backhoe according to the present invention. The basic configuration of this backhoe is not particularly different from the well-known one, and the swivel base 4 can be swiveled all around the vertical axis X on a track frame 3 provided with a pair of right and left crawler traveling devices 1 and a discharge plate 2. A driving unit 7 with a driving unit 5 and a sunshade 6 is provided on the swivel 4, and a front device 8 for excavation work is provided on the right side of the driving unit 7.

The front device 8 comprises a boom cylinder C1, an arm cylinder C2, and a boom cylinder C1, an arm cylinder C2, and a boom 10, an arm 11, and a bucket 12, which are sequentially connected.
The boom 10 is driven to bend and extend and undulate by a bucket cylinder C3, and the boom 10 is driven by an offset cylinder C4 to bend horizontally and in parallel via a pair of joint fulcrums Y1 and Y2. A so-called ultra-small swivel type backhoe that can be folded to the right side and swivel with a small radius together with the swivel base 4 is configured.

At the base of the boom cylinder C1, the base of the arm 11, and the joint fulcrum Y1 of the boom 10, angle sensors S1, S2, S3 using potentiometers are provided, respectively. These angle sensors S1, S2,
The bucket pin 1 provided at the tip of the arm from the detection result of S3
The position of the bucket 7 is recognized, and the angle sensors S1 and S2 are arranged so as to prevent the bucket pin 12a from intruding and moving toward the driving unit 7 from the preset regulating surfaces Z1 and Z2 in front of and right side of the driving unit 7. By controlling the operations of the boom cylinder C1, the arm cylinder C2, and the offset cylinder C4 based on the information from S2 and S3, interference prevention control for avoiding the bucket 12 from interfering with the driving unit 7 is executed. It has become so.

FIGS. 2 and 3 schematically show a hydraulic circuit for driving the backhoe and an operating hydraulic circuit.
In the figure, V1 and V2 are control valves for the traveling hydraulic motors M1 and M2 for driving the left and right crawler traveling devices 1, and V3 is a turning hydraulic motor M for driving the swivel table 4.
V4 is a control valve for the boom cylinder C1, V5 is a control valve for the arm cylinder C2,
6 is a control valve for the bucket cylinder C3, V7 is a control valve for the offset cylinder C4, V8 is a control valve for the dozer cylinder C5 that moves up and down the soil discharge plate 2, and V9 is a control valve for the service port. P1 and P2 are working pumps, and P3 is a pilot pump for supplying a pilot pressure for operating a control valve.

Here, the traveling control valves V1 and V2
Are mechanically interlocked with left and right control levers 14 provided at the front of the driving unit 7 and are directly artificially operated by the driver. The control valve V8 for the dozer cylinder C5 and the control valve for the service port are also provided. V9 is the driving unit 7
Are mechanically linked to pedals and levers (not shown) provided in the vehicle, and are directly artificially operated by the driver. The control valve V3 for turning, the control valve V4 for the boom, which controls the attitude of the front device 8, the control valve V5 for the arm, and the control valve V6 for the bucket are configured by a pilot operation type. A pair of pilot valves PV1 and PV2 for supplying pilot pressure are operated by a pair of left and right working levers 15 and 16 provided at the front of the operating unit 7. The control valve V7 for offset is also of a pilot-operated type, and a pilot valve PV3 for supplying a pilot pressure to the control valve V7 is operated by a pedal 17 provided at the foot of the operating unit 7. The work levers 15 and 16 are each configured in a cross-operation manner. The boom is lowered by operating the right working lever 16 forward, the boom is raised by operating backward, the bucket is scraped by the left operation, and the bucket dump is operated by the right operation. The arm is swung out by operating the left working lever 15 forward, the arm is scraped by operating backward, the left turning is performed by left operating, and the right turning is performed by right operating.

As shown in FIG. 3, the pilot valves PV1,
PV2, PV3 and each control valve V3, V4, V5, V6, V
7 are provided in the pilot hydraulic circuit with electromagnetic proportional control valves MV1, MV2, MV for performing the interference prevention control.
3 and MV4 are interposed, each of which is the angle sensor S1.
, S2 and S3 are connected to the controller 20.

The solenoid proportional pressure control valve MV1 is interposed in a boom raising pilot oil passage a, and controls the raising operation of the boom 10. The electromagnetic proportional control valve MV2 is interposed in the arm oil scraping pilot oil passage c, and controls the arm 11 scraping operation. The electromagnetic proportional pressure control valve MV3 is interposed in the pilot oil passage i for boom left offset, and controls the left offset operation of the boom 10. Further, the electromagnetic proportional pressure control valve MV4 is interposed in a pilot oil passage d for swinging the arm, and controls the swinging operation of the arm 11 forward.

Each electromagnetic proportional pressure control valve MV1, MV2, M
The operation of V3 and MV4 is controlled based on the detection results of the angle sensors S1, S2 and S3. The position of the bucket pin 18 recognized from the detection results of these angle sensors S1, S2 and S3 is determined by the operation unit. When approaching a predetermined regulating surface in front of and on the right lateral side of 7, the pressures of the pilot oil passages a, c, and i are further suppressed by the electromagnetic proportional pressure control valves MV1, MV2, and MV3, and the boom is raised. When the arm scraping operation and the left offset operation are decelerated and the bucket pin 18 reaches the regulating surfaces Z1 and Z2, the pilot oil passages a, c and i are controlled to be shut off, and the boom raising operation is further performed. The arm scraping operation and the left offset operation are prevented.
If the position of the bucket pin 18 approaches a predetermined distance from the regulating surface Z1 when the boom is raised and the arm is scraped at the same time, the electromagnetic proportional pressure control valve MV4
Is operated, the arm 11 is automatically operated in the swinging direction, and the boom raising operation is continued. As a result, the bucket pin 18 is not stopped along the surface set a predetermined distance before the regulating surface without stopping. Control for moving upward is performed.

Also, in the boom raising operation, the boom 1
When 0 approaches its rising limit, the following impact mitigation control is performed.

When the boom 10 is near its upper limit,
When the approach of the stroke end of the boom cylinder C1 in the extension direction is detected by the detection result from the angle sensor S1 for detecting the boom angle, the electromagnetic proportional control valve MV
The current applied to 1 is controlled with a predetermined characteristic, the opening of the control valve is gradually reduced, the boom rising speed gradually decreases, and the rising limit is reached without impact.

The controller 20 is provided with a rewritable storage medium 21 such as a non-volatile memory, and the like. Are stored and stored in a plurality of types of specifications, and are read out arbitrarily and used as data for the interference prevention control.

A suspension link 22 is pivotally connected to a link fulcrum R of a bracket 12a provided on the back surface of the bucket 12. The suspension link 22 is stored and held behind the bracket 12a when the front device 8 is used for a normal excavation operation, and when the crane operation is performed using the front device 8, the suspension link 22 shown in FIG.
As shown in FIG. 5, the hanging member 23 such as a hook is attached by being swung out at the back of the bucket 12 in the scraping posture.

As described above, when the front device 8 is used for crane work, the crane work mode is selected by switching the work mode selection switch 24 connected to the controller 20, and the machine body is prevented from tipping over due to the hanging load. Is performed. When the crane operation mode is selected, the patrol light 25 provided in the operation unit 7 is turned on and turned to notify surrounding workers that the crane operation is being performed.

Here, in the pilot hydraulic circuit connecting the pilot valves PV1, PV2 and the control valves V3, V4, V5, V6, V7, there are provided electromagnetic proportional control valves MV5, MV6, MV7 for controlling the crane operation. , And each is connected to the second controller 26. Also,
The controller 20 is provided with a liquid crystal display device 28, and a pressure sensor PS is connected to an oil passage on the pressure oil supply side when the boom cylinder C1 is raised. The load pressure generated in the cylinder C1 is detected.

In the crane operation mode,
Based on the front device attitude information, the horizontal position from the turning center X to the suspension point (link fulcrum) R is determined, and from the load pressure acting on the boom cylinder C1,
The suspended load acting on the suspended point R is calculated, and the calculated suspended load, the calculated suspended radius, and the rated suspended load that can be safely suspended by the front device 8 are calculated by the liquid crystal display device 26. Displayed side by side or sequentially
The driver can be made to know the current work situation. In the crane operation mode, the pilot oil passage f is shut off by the electromagnetic proportional control valve MV5 so that the bucket 12 in the raked position is not inadvertently dumped. And the electromagnetic proportional control valves MV6, MV
By V7, the maximum pilot pressure that can be applied to the turning control valve V3 is limited to a low value, and the maximum turning speed is suppressed. Further, when the calculated lifting load approaches the rated lifting load more than the set value, a warning is issued from the warning device 27 to draw attention.

In this crane operation control, if the specifications of the front device 8 are changed by replacing the arm 11 or the boom 10 with a different length, the changed parameters are read out from the storage medium 21 and set. By doing so, fall prevention control corresponding to the changed specification is performed.

[Brief description of the drawings]

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

FIG. 2 is a hydraulic circuit diagram

FIG. 3 is an operation pilot circuit diagram.

FIG. 4 is a side view illustrating an interference prevention control operation.

FIG. 5 is a plan view illustrating an interference prevention control operation.

FIG. 6 is a control block diagram.

[Explanation of symbols]

 7 operation unit 8 front device 12 bucket C1 boom cylinder PS pressure sensor

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Atsushi Matsumoto 64 Ishizu-Kitacho, Sakai-shi, Osaka F-term in Kubota Sakai Works Co., Ltd. (Reference) 2D003 AA01 BA07 BB03 BB11 DA03 DA04 DB02 DB04

Claims (3)

[Claims] 1. A backhoe comprising interference prevention control means for restraining the operation of the front device based on the attitude detection of the front device so as to prevent the bucket from entering the driving section. A backhoe wherein parameters to be determined are stored in rewritable storage means, and arbitrary parameters are read and used. 2. A crane function comprising: means for detecting the attitude of the front device and calculating a horizontal position of a load suspension point at the front device front end; and means for calculating a load acting on the load suspension point. In the attached backhoe, a parameter for calculating the position of the load suspension point in the front device is stored in rewritable storage means,
A backhoe characterized in that any parameter can be read and used. 3. The backhoe according to claim 2, further comprising a pressure sensor for detecting a negative pressurization of the boom cylinder in the front device, and configured to calculate a suspension load based on the detected load pressure.