JPH02296580A - Self-propelling working machine of walking type - Google Patents

Abstract

PURPOSE:To prevent the subject working machine from running unexpectedly and increase the safety by providing a non-contact type operator existence sensor for detecting whether a standing operator is existing near a steering handle, and automatically stopping a machine body upon detecting the non existence of the operator. CONSTITUTION:A crawler walking type mower has an engine start key switch 9, a cutter clutch lever 10 for turning on and off drive power, and a travel clutch lever 11 for turning on and off power transmission to a rear wheel respectively on a frame 8 extended between a pair of right and left steering handles 7 and 7. ln this case, a supersonic sensor is so fitted to the intermediate part of the frame 8 as to be directed aft as an operator existence sensor 12. In addition, when a transmitted signal wave from the supersonic sensor 12 does not return with the travel clutch lever 11 turned on, or a reflected wave is detected in or after the predetermined time, a control device judges that there is no operator M near the steering handles 7, and interrupts fuel supply to an engine for stopping the operation thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a self-propelled walk-behind work machine, such as a walk-behind lawnmower, in which an operator grips a control handle to perform work.

[Conventional technology]

In a walk-behind lawn mower, which is a type of self-propelled walk-behind work machine, for example, as shown in Fig. 4, a loop-shaped fixed control handle (17) is replaced with a similar arch-shaped latch lever that moves. (18) is attached to be vertically swingable around the horizontal axis (Pl), and the latch lever (18) running with a spring (not shown) or the like is urged toward the cutting side.

As a result, the operator lifts the running latch lever (18) toward the control handle (17), engages the running latch, and engages the running latch lever (17) and the running latch lever (17).
18) Hold both. The travel latch is now engaged and the aircraft moves forward, and the pilot follows the aircraft while holding the control handle (17) and the travel latch lever (1B>).

The operator may fall and the control handle (17)
When the latch lever (18) that moves is released, the latch lever (18) that moves returns to the cutting side due to the biasing force of the spring and the machine automatically stops, thereby preventing the walk-behind lawn mower from running out of control. I try not to do it.

[Problem to be solved by the invention]

With the above-mentioned structure, during lawn mowing work, the latch lever, which moves against the biasing force toward the clutch disengagement side, must be held in the engaged position at all times. The pilot becomes easily fatigued. Also, if the machine body moves up and down on an uneven surface during lawn mowing work and you take your hand off it, the machine will automatically stop.

In other words, the aircraft will stop even when there is no need to stop the aircraft, so there is room for improvement in terms of improving work efficiency.

Here, the present invention aims to solve the above-mentioned problems while retaining the safety function of automatic stop.

[Means to solve the problem]

The features of the present invention include, in the self-propelled walk-behind work machine as described above, a non-contact type operator presence/absence sensor that detects whether or not an operator is present in a standing position near the operating handle;
The aircraft is equipped with an automatic stopping means for stopping the aircraft based on the detection of the absence of the pilot, and its functions and effects are as follows.

[For production]

In self-propelled walk-behind work machines such as walk-behind lawn mowers, there is no need for the operator to hold the control handle at all times while the machine is running, and it is necessary to correct the direction of the machine or stop unexpected movement of the machine. If the vehicle is moving in a stable straight line, the operator can easily grasp the steering wheel and there is no problem even if the operator takes his hands off the steering wheel. do not have.

Therefore, if configured as described above, the aircraft will automatically stop only if the operator falls and becomes too far away from the control handle.

〔Effect of the invention〕

This eliminates the need for the latch lever, which runs against the biasing force toward the cut side, to be held in the clutch engaged position all the time during operation, as in the conventional structure, and reduces fatigue for the operator. If the operator is close to the control handle, the machine will not stop even if he or she takes his hand off the control handle, so the machine will not stop frequently and be forced to interrupt work, and this will prevent a drop in work efficiency. .

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings using a walking lawn mower, which is one of the self-propelled walking working machines.

As shown in Figure 3, a mower (5) equipped with three rotary cutting blades (4) is attached to the lower part of the machine body (3) supported by the front wheels (1) and rear wheels (2). A self-propelled walk-behind lawn mower is provided with an engine (6) in the center of the machine body (3), a grass collection container (19) and a control handle (7) at the rear of the machine body.

As shown in FIG. 1, the control handles (7) are rod-shaped and are provided in pairs on the left and right sides, and grips (7a) are attached to the ends thereof. A frame (8) is installed across both control handles (7), and a key switch (9) for starting the engine (6) is mounted on this frame (8).
A mower blade clutch lever (10) is provided to perform important operation of power to the mower (5), and a running latch lever (11) is provided to perform important operation of power to the rear wheels (2).

In the center of the frame (8) is a pilot presence/absence sensor (
The ultrasonic sensor 12) is attached facing backward (downward in the paper). Therefore, the latch lever (1
1) is inserted and operated, the ultrasonic sensor (12
) does not return or is detected by the ultrasonic sensor (12) as a reflected wave after a set time, the operator (M ) is not present, the control device (13) determines that there is no fuel pipe (1) from the fuel tank (14) to the engine (6).
The on-off valve (16) (5) is closed by the control device (13), and the aircraft automatically stops.

Conversely, if the starting wave from the ultrasonic sensor (12) is detected by the ultrasonic sensor (12) as a reflected wave within the set time while the latch lever (11) for running is in the engaged state, the steering starts. It is determined that the operator (M) is near the handle (7), and the closing operation of the on-off valve (16) is not performed.

[Another example]

An infrared or optical distance sensor may be used as the operator presence/absence sensor (12).

In addition, when the operator (M) is not near the control handle (7), the engine (6) may be operated without stopping (by turning off the latch that allows the engine to run), and at the same time, the mower clutch It is even safer to perform the cutting operation.

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 drawings]

The drawings show an embodiment of the self-propelled walking type work machine according to the present invention, in which Fig. 1 is a plan view of the vicinity of the operating handle, Fig. 2 is a schematic diagram showing an automatic stop system for traveling, and Fig. 3 is a walking type work machine. FIG. 4 is an overall side view of the lawnmower, and is a perspective view of the vicinity of the control handle in a conventional structure. (7)... Control handle, (12)...
・Pilot presence/absence sensor

Claims (1)

[Claims] A non-contact type operator presence/absence sensor (
12) and an automatic stopping means for stopping the machine based on detection of the absence of an operator.