JPH01296906A - Lifting control device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a system in which a detection signal from a position sensor that detects the level of a working device relative to a vehicle body and a setting signal from a manually operated position setting device are balanced. a position control mechanism that drives the work equipment up and down, and a position control mechanism that drives the work equipment up and down so that the detection signal from the level sensor that detects the ground level of the work equipment and the setting signal of the manually operated ground level setter are balanced. The present invention relates to an elevation control device that is equipped with a ground level control mechanism, and more particularly, to an improvement in a check means that prevents descending control of a working device at the time of starting an engine.

[Conventional technology]

Conventionally, as an elevator control device having a check means as described above, there is a device such as that shown in Japanese Patent Application Laid-Open No. 152205/1983.

[Problem to be solved by the invention]

Additionally, in this reference, when the engine is started, the position control mechanism for adjusting the level of the work equipment relative to the vehicle body and the ground level control mechanism for adjusting the level of the work equipment relative to the ground must be configured so that they cannot be controlled in the downward direction. For example, when stopping,
Even if the control target level of the working device is erroneously operated to a low level side, the work safety is ensured without causing any inconvenience such as lowering the working device when the engine is started.

Also, in order to release the restraining state in this reference, at least
It is necessary to perform an operation to change the control target of the position control mechanism in the upward direction to a position corresponding to the level of the working device.

However, in the lifting drive system of the working equipment, a mechanical lifting limit of the working equipment is determined, and the lifting control limit of the position control mechanism is set at a level lower than this lifting limit. If you directly operate the lifting hydraulic cylinder to raise and lower the level of the working equipment above the limit of the lifting control of the position control mechanism, the control system will inevitably go into check mode when the engine starts. Since the working device is in the uncontrollable range, even if the control target of the position control mechanism is changed to the upper limit, the restraining state cannot be released and there is room for improvement.

Incidentally, the upward control limit in the position control mechanism is
If it is determined by the position of the dial for setting the target level or the stopper for setting the operating limit of the lever, and the check state cannot be released as described above, the check state can be released by changing the position of the stopper. Sometimes it is possible to cancel.

The purpose of the present invention is to improve, through reasonable modification, a control system that can easily release the check state without compromising safety even if the work equipment is at a level higher than the lift control limit. There are some points that are easy to configure.

[Means to solve the problem]

A feature of the present invention is that the lift control device is provided with a check means for preventing the position control WJ mechanism or the ground level control mechanism from being controlled to the descending side when the engine provided in the vehicle body is started, and the check means If the work equipment is located at a level close to the mechanical lift limit in a check state due to A restraint release means is provided at a corresponding position to release the restraint by operating the position setting device, and its functions and effects are as follows.

[For production]

If the above characteristics are configured as shown in FIG. 3, for example, when the lift arm (10) that suspends and supports the working device (12) is located at a level higher than the rise limit of the position control, as shown in FIG. is the mechanical rise limit (L0)
Operate the position setting device (15) to a position corresponding to a level (L,) set a predetermined amount lower based on , or to a position corresponding to a check release area formed in an area higher than this level (L1). By doing so, you can release the restraint.

In addition, in the flowchart of Figure 2, this check can be released.
#5 It is represented by step.

〔Effect of the invention〕

Therefore, by creating an area for releasing the restraint based on the mechanical ascent limit of the working equipment, even if the working equipment is located at a level above the control area, safety will not be compromised. Moreover, a control system that can easily release the check state has been constructed in a relatively simple manner.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in Figure 4, an engine (1) and a main clutch (2) are arranged in a connected state at the front of the vehicle body, and a transmission case (3) is arranged at the rear of the vehicle body. The running system of the agricultural tractor is configured so that the power is transmitted to the front and rear wheels (4) and (5), respectively.

In this agricultural tractor, a driver's seat (7) is provided above the transmission case (3) at a position midway between the left and right rear fenders (6), and a steering handle (8) is provided in front of the driver's seat (7). A pair of left and right lift arms (10), (10) are provided on the upper part of the transmission case (3), which are raised and lowered by the operation of a hydraulic cylinder (9), and a two-point link mechanism (11) is installed on the rear surface of the transmission case (3). A rotary type work device (12) is provided through the work device (12).
By supporting the lift arms (10), (10) via the lift rods (13), (13), the level of the work equipment (12) can be adjusted by driving the lift arms (10), (10) during work. It is configured to be adjustable.

In addition, in order to control the lifting and lowering of the working device (12), a position setting device (15) operated by a lever (14) is arranged on the side of the driver's seat (7) as shown in FIG. A potentiometer-type position sensor (16) is attached to the base end of (10) to detect the level of the working device (12) relative to the vehicle body from the swing angle of the lift arm (lO).
Control box (1) installed on the rear fender (6)
7) is equipped with a ground level setting device (19) operated by a dial (18), and the working device (12) is equipped with a rear cover (1).
Work bag from the swinging position of 2a)! A potentiometer-type level sensor (20) is provided to detect the ground level of the working device (12), and signals from these sensors are used to detect the level of the working device (12).
), the control device (A) that raises and lowers the control box (
17).

As shown in FIG. 3, the control system of the working device (12) raises and lowers the working device (12) until the setting signal from the position setting device (15) and the detection signal from the position sensor (16) are balanced. and a position control mechanism (B) that operates to set the working device (12) to an arbitrary level relative to the vehicle body.
), the working device (12) is raised and lowered until the setting signal from the ground level setter (19) and the detection signal from the level sensor (20) are balanced, and the working device (12) is set to the desired ground level. A ground level control mechanism (C) that operates to set the level to 15)
If the setting level of is on the lower side, the working device (12)
A restraining means (D) for preventing elevation control and a restraining release means (E) for releasing the restraining state are provided to ensure work safety.

The operation by the position control mechanism (B) is referred to as position control, and the operation by the ground level control mechanism (C) is referred to as automatic plowing depth control, and the position control area based on the lift arm (10) is the first It is represented as shown in the figure.

In addition, the checking state can be released by operating the position setting device (15) to a position corresponding to the level of the working device (12) or to a position on the high level side, or by moving the working device (12) mechanically. If the level is near the rise limit (L0), the position is set to a position corresponding to a level (LL) set a predetermined amount lower than the mechanical rise limit (L0), or to a high level position. Vessel (15
).

Of the above-mentioned check release operations, the former operation is the first one.
The latter operation involves operating the position setter (15) within the restraint release area, and within the second restraint release area.

In addition, the control device (A) is a microprocessor (not shown).
In addition, it is equipped with a position control 'a mechanism (B), a ground level control mechanism (C), a check means (D), and a check release means (
E) Each consists of a program set in a memory (not shown), and its operation is expressed as in the flowchart of FIG.

In other words, the key switch for starting the engine (shown in Figure 3)
21) is turned on, first the position sensor (1
6) Please input the detection signal from II! Step), Next, it is determined whether the level of the working device (12) is in the uncontrollable range (+12 step). If it is determined that it is in this range, a predetermined signal is sent in place of the signal from the position sensor (16). Input the value (the signal value corresponding to the lower level (Lo)) (Step #3).

Next, a setting signal from the position setting device (15) is input (step #4) and compared with the human input signal (step #5). As a result, if the direction of position control is downward, no movement is performed and the check state is set, and if the direction of position control is upward, the work bag is set! (12) is increased (#6
step), if it is in a balanced state, it is set to a check release state with the flow of +16 steps.

Also, the checking state is released by operating the position setting device (15) in the upward direction, and when the checking state is reached, the setting signal from the position setting device (15) and the ground level setting device are activated. Input the setting signal from (19) (Steps #7 and #8), and determine the control mode from each value (Step #9). As a result, the setting signal from the ground level setting device (19) If the level is on the high level side, automatic tilling depth control is determined, and the detection signal from the level sensor (20) is input (Step #10), and feedback control is performed so that this detection signal and the setting signal are balanced (
#11 step), and if the setting signal on the position setting device (15) side is on the high level side in step #9, it is determined that position control is being performed, and the detection signal from the position sensor (16) is input. #12 Step), feedback control is performed so that this detection signal and setting signal are balanced (Step #12), and the control mode is determined in this way and the control continues until the key switch (21) is turned off. It is supposed to be done.

Incidentally, the signal from the control device (A) is output to the solenoid valve (22), and the hydraulic cylinder (9) is controlled by this solenoid valve (22), and the solenoid valve (22) is directly operated. Switch (23) that controls the hydraulic cylinder (9)
are also provided.

In addition, in this embodiment, a check means (D) and a check release means (E)
is also used as step #5 in the flowchart, the position control mechanism (B) is configured in step 1113 in the flowchart, and the ground level control mechanism (CC) is configured in step #11 in the flowchart.

[Another example]

In addition to the embodiments described above, the present invention includes, for example, a check means, a check release means, a position control mechanism, and a part or all of the ground level control mechanism configured with a hard circuit consisting of a combination of logic gates, comparators, etc. The control system can be implemented in various ways, and the sensors can also have various structures.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawings show an embodiment of the elevation control device according to the present invention, and the first embodiment
2 is a flowchart showing the operation of the control device, FIG. 3 is a block circuit diagram of the control system, and FIG. 4 is a side view of the entire agricultural tractor. (1)...Engine, (12)...Working device, (15)...Position setting device, (1
6)...Position sensor, (19)...
... Ground level setting device, (20) ... Level sensor, (B) ... Position control mechanism, (C)
...Ground level control mechanism, (D)...
Checking means, (E)...Checking release means, (L0)
...Limit of rise, (L1)...Level.

Claims (1)

[Claims] The work device (12) is driven up and down so that the detection signal from the position sensor (16) that detects the level of the work device (12) relative to the vehicle body is balanced with the setting signal from the manually operated position setting device (15). The detection signals from the position control mechanism (B) and the level sensor (20) that detects the ground level of the working device (12) are balanced with the setting signal of the manually operated ground level setting device (19). A lifting control device equipped with a ground level control mechanism (C) for driving and lifting a working device (12),
A check means (D) is provided that prevents the position control mechanism (B) or the ground level control mechanism (C) from controlling the descending side when the engine (1) provided in the vehicle body is started, and this check means (D), when the working device (12) is located at a level near the mechanical ascent limit (L_0), the level ( By operating the position setting device (15) to a position corresponding to L_1) or a position corresponding to a level higher than this level,
An elevation control device comprising a restraint release means (E) for releasing restraint.