JPH0679266B2 - Neutral self-diagnosis device for operating lever - Google Patents

Description

TECHNICAL FIELD The present invention relates to a neutral self-diagnosis device for an operating lever in a work machine control device.

(Prior Art) As a control device for a working machine, for example, as a boom rocking control device for a tractor-mounted backhoe, command means (potentiometer or the like) that outputs a command signal proportional to the tilt angle of the operating lever is provided to control rocking. When the operating lever is tilted by a certain angle at this time, the control valve operates in the tilt direction of the operating lever at an opening proportional to the tilt angle by the command signal from the commanding means, and the hydraulic oil from the hydraulic pump interlocking with the engine is operated by the control valve. There is a device which is supplied to the swing cylinder via.

This control device, like the control valve for normal manual operation, swings the boom at a speed proportional to the tilt angle of the operation lever, despite operating the operation lever to electrically control the control valve. Therefore, even when various automatic control functions are added to the drive circuit of the control valve, there is an advantage that the control valve can be operated with the same feeling as for manual operation.

(Problems to be Solved by the Invention) The operating lever is normally configured to return to a neutral state by a spring or the like, but is not always in a neutral state due to damage to the spring, biting of foreign matter, or the like. . Therefore, conventionally, if the operation lever is outside the neutral range, a command signal is output from the command means when the key switch of the engine is turned on and the power is turned on. There was a fear that he would suddenly rock.
In particular, in the case of a tractor-mounted backhoe, the key switch for starting the engine of the tractor and the control section side such as the operation lever on the backhoe side are widely separated, so even if the boom of the backhoe suddenly starts moving as described above. , The operator could not return the operation lever to the neutral position without moving from the tractor to the backhoe side, which was very dangerous.

In view of such conventional problems, the present invention self-diagnoses whether or not the operating lever is in the neutral range when starting the engine, and enables the control valve if it is in the neutral range. The purpose is to prevent malfunctions immediately after the engine is started by issuing a warning.

[Means for Solving the Problem] In the present invention, the command means 31 proportional to the tilt angle of the operation lever 29 is used.
The control valve 33 is operated by a command signal from the engine 6
In the working machine control device in which the hydraulic oil from the hydraulic pump 34 interlocked with is supplied to the hydraulic cylinders 23 and 24 through the control valve 33, the signal from the command means 31 is sent when the key switch 35 of the engine 6 is turned on. Storage means for inputting and storing 38
And a start detecting means 37 for detecting the start of the engine 6, and a determining means for determining whether the stored signal of the storing means 38 is in the neutral range of the operating lever 29 after the start detecting means 37 detects the start of the engine 6. 39, an actuating means 34 for enabling the control valve 33 when the discriminating means 39 discriminates that it is in the neutral zone, and an alarm means 42 for giving an alarm when the discriminating means 39 discriminates that it is outside the neutral zone.

(Operation) The operation will be described with reference to the flowchart shown in FIG.

When the key switch 35 is turned on and the power is turned on when the engine 6 is started (step), the command signal of the command means 31 is input to the storage means 38 and the lever state is detected (step). That is, since the command means 31 outputs a command signal proportional to the tilt angle of the operating lever 29, a signal corresponding to the tilt angle of the operating lever 29 is input and stored in the memory means 38 (step). Next, when the key switch 35 is started, the stark
36 operates and the engine 6 starts. When the engine 6 is started, the lubricating oil pump is driven,
The start detection means 37 such as an oil switch detects the start of the engine 6 (step), and determines the engine start (step). That is, the signal from the command means 31 is input and stored between the time when the key switch 35 is turned on and the time when the engine 6 is started. If the operation lever 29 moves during this time and the signal of the command means 31 changes, the changed signal is input and stored.

When the start detecting means 37 detects the start of the engine 6, the discriminating means 39 reads the storage signal of the storing means 38 and discriminates whether or not it is in the neutral range A (step). Then, if the stored signal has a value indicating the inside of the neutral range A, the initial state of the operating lever 29 is judged to be normal, the operating means 41 is operated to enter the normal control mode (step), and the control valve 33 can be operated. To be in a good state. On the other hand, if the memory signal indicates B outside the neutral range, the initial state of the operating lever 29 is judged to be abnormal, and the alarm means
An alarm is issued by 42 (step). Therefore, when the engine 6 is started, it can be self-diagnosed whether or not the operating lever 29 is in the neutral range A, and according to the result of the diagnosis, the control valve 33 can be operated in the neutral range A and outside the neutral range. If it is B, an alarm is issued, so that a malfunction after the engine 6 is started can be prevented.

Further, even when the command means 31 is disconnected or short-circuited, zero or the power supply voltage + V is input, so that an abnormality due to them can be diagnosed.

After the engine 6 is started, the signal of the command means 31 is not input as self-diagnosis.

(Example) Hereinafter, the present invention will be described in detail with reference to the illustrated example.
In the figure, 1 is a tractor vehicle body, 2 is a front wheel, and 3 is a rear wheel. 4 is a steering wheel, 5 is a driver's seat, and 6 is an engine.

Reference numeral 7 denotes a front loader mounted on the front part of the tractor vehicle body 1, including a mast 8 mounted on both left and right sides of the tractor vehicle body 1, a boom 9 pivotally attached to an upper end of the mast 8 so as to be vertically movable, It has a boom cylinder 10 for moving the boom 9 up and down, a bucket 11 pivotally attached to the tip of the boom 9, and a bucket cylinder 12 for rotating the bucket 11.

Reference numeral 13 denotes a backhoe attached to the rear end of the tractor body 1, and includes a machine frame 14 attached to the tractor body 1 and a machine frame 14.
14, a rocking base 16 pivotally mounted about a vertical axis 15 about a vertical axis, a boom 17 pivotally mounted on the rocking base 16 so as to be vertically movable, and a boom 17
An arm 18 pivotally attached to the tip of the arm 18, a bucket 19 pivotally attached to the tip of the arm 18, a control box 20 and a driver's seat 21 provided on the rocking base 16. . As shown in FIG. 4, the rocking platform 16 is supported by a pair of upper and lower brackets 22 protruding rearward from the machine frame 14 via a vertical axis 15, and near the lower bracket 22 the machine frame 14 and the rocking platform 16 are supported.
It is rocked by a pair of rocking cylinders 23 and 24 on the left and right that are interposed between the rocking cylinders. A detection means 25 such as a potentiometer for detecting the swing position of the swing base 16 is attached to the swing base 16. The boom 17 is vertically movable by a boom cylinder 26, the arm 18 is freely bendable by an arm cylinder 27, and the bucket 19 is freely rotatable by a bucket cylinder 28.

On the upper surface side of the control box 20, as shown in FIG. 5, two operation levers 29 and 30 which are swingable back and forth and left and right are provided side by side. When the operation lever 29 is operated left and right, the swing base 16 swings left and right, and when the operation lever 29 is operated back and forth, the boom 17 moves up and down. Operating lever 30
Bucket 19 squeezes and dumps when operated left and right,
The arm 18 expands and contracts when it is operated back and forth.

As shown in FIG. 1, the operating lever 29 is interlocked with a command means 31 such as a potentiometer provided on the base side of the operating lever 29, and the neutral area N in the control mode and the high speed positions LH at the left and right ends,
It is possible to operate to the left and right with the RH to any tilt angle.

In FIG. 1, the command means 31 is configured to output a command signal (voltage signal) proportional to the tilt angle of the operating lever 29. Reference numeral 32 is a swing control means, which determines the swing direction and swing speed of the swing base 16 or the boom 17 based on a command signal from the command means 31 and a detection signal from the detection means 25, and a control valve It is designed to activate 33. The control valve 33 is for supplying hydraulic oil from the hydraulic pump 34 interlocking with the engine 6 to the oscillating cylinders 23 and 24, and is constituted by a flow rate proportional type directional control valve. Reference numeral 35 is a key switch for starting the engine 6, and the starter 36 of the engine 6 is activated when the starting operation is performed after the power is turned on. Reference numeral 37 is a start detection means for detecting the start of the engine 6, and is constituted by an engine lubricating oil system oil switch or the like. 38 is a storage means, 39 is a discrimination means, and these are constituted by a microcomputer 40. The storage means 38 stores the command means 31 when the key switch 35 is turned on.
The command signal from is input and stored. The discriminating means 39 discriminates whether the stored signal of the storing means 38 is the neutral area A or the neutral area B after the start detecting means 37 detects the start of the engine 6. Reference numeral 41 denotes an actuating means for turning on the control valve 33 so that the signal from the rocking control means 32 can be output to the control valve 33 so that the control valve 33 can be operated when the discriminating means 39 determines the neutral area A. Is. Reference numeral 41 is an alarming means such as an LED, which is for issuing an alarm to the operator when the determining means 39 determines that the area B is outside the neutral range. The neutral zone A for self-diagnosis
Is set to be smaller than the neutral range N in the control mode so that malfunction does not occur due to vibration of the operating lever 29 and backlash.

The actuating means 41 may turn on / off the entire control means 32.

It can also be carried out on work machines other than the backhoe 13.

(Effect of the Invention) According to the present invention, the storage means 38 for inputting and storing the signal from the command means 31 when the key switch 35 of the engine 6 is turned on.
And a start detecting means 37 for detecting the start of the engine 6, and a judging means 39 for judging whether the stored signal of the storing means 38 is in the neutral range of the operating lever 29 after the start detecting means 37 detects the start of the engine 6. The operating means 34 for enabling the control valve 33 when the discriminating means 39 discriminates that it is in the neutral region, and the alarm means 42 which warns when the discriminating means 39 discriminates that the engine 6 is out of the neutral region. At the time of starting, it is possible to diagnose whether or not the operating lever 29 is in the neutral range A, and therefore, it is possible to prevent the malfunction of the engine 6 after starting, and the safety is remarkably improved. Moreover, the abnormality of the command means 31 can be diagnosed.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, FIG. 1 is a block diagram,
2 is a flow chart, FIG. 3 is a side view, FIG. 4 is a cross-sectional plan view of the rocking base, and FIG. 5 is an explanatory view of the operating lever. 6 ... Engine, 13 ... Backhoe, 23, 24 ... Oscillating cylinder (hydraulic cylinder), 29 ... Operating lever, 31 ... Command means, 33 ... Control valve, 34 ... Hydraulic pump, 35 ... Key switch, 37 ... Start detection means, 38 ... Storage means, 39 ...
... discriminating means, 41 ... actuating means, 42 ... warning means, A ...
Neutral zone.

Claims (1)

[Claims] 1. A control valve (33) is operated by a command signal from a command means (31) in proportion to a tilt angle of an operating lever (29), and an operation from a hydraulic pump (34) interlocking with an engine (6). Oil through control valve (33) to hydraulic cylinders (23) (2
In the working machine control device adapted to supply to the 4), a storage means (38) for inputting and storing a signal from the command means (31) when the key switch (35) of the engine (6) is turned on.
And a start detection means (3 for detecting the start of the engine (6)
7) and a determination means (39) for determining whether the storage signal of the storage means (38) is in the neutral range of the operation lever (29) after the start detection means (37) detects the start of the engine (6). And an actuating means (34) for enabling the control valve (33) when the discriminating means (39) discriminates that it is in the neutral range, and an alarm means (42) which gives an alarm when the discriminating means (39) judges that the control valve (33) is outside the neutral range A neutral self-diagnosis device for the operating lever, which is provided with.