JPS5842068B2 - Walking work vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a walk-behind working vehicle that is configured so that the extending direction of a control handle can be freely changed back and forth and is equipped with a forward and backward switching device.

When moving the machine backwards with a walk-behind work vehicle, there are cases where the operator is unable to stop the machine due to the operator falling, etc. There was a risk of injury.

As a means to avoid such danger, there is
As shown in Publication No. 38306, a device that detects whether the steering wheel is in the grip state is connected to the engine stop device and automatically stops the aircraft when the operator releases the steering wheel. However, with such a configuration, the aircraft will stop when you release your hand from the handle grip state detection device, regardless of the direction in which the aircraft is moving. Because of this, it is necessary to always grasp the handle accurately while working, which can easily lead to worker fatigue, and it is also difficult to perform other tasks at the same time by temporarily letting go of the handle. There were some inconveniences such as not being able to.

The technical problem to be solved by the present invention is that the aircraft does not stop when you take your hands off the handle whether the aircraft is moving forward or backward, but only when the aircraft is moving backwards, which is particularly important for the safety of the operator. The disadvantages of the above-mentioned conventional technology are solved by configuring the vehicle to stop, and the technology for stopping the vehicle only when moving backwards is applied to a walk-behind work vehicle in which the direction of the control handle can be changed freely. In order to ensure the safety of the operator, who holds the control handle after the orientation has been changed, the aircraft is stopped only when the aircraft is moving backwards.

The technical means of the present invention taken to solve the above problems are as follows:
As described above, in the walk-behind work vehicle, which is equipped with a device that can freely change the traveling direction of the machine body back and forth, and is configured so that the direction of the control handle can be changed back and forth, a steering wheel orientation detection mechanism that detects whether the steering wheel is in a grip position; a switching device operation state detection mechanism that detects whether the forward/reverse switching device is operated to tilt forward or backward; and a switching device operation state detection mechanism that detects whether the steering wheel is in a grasped state. A grip state detection mechanism for detecting whether or not the aircraft is moving is incorporated into the control circuit of the engine stop device, and further, this control circuit is configured to detect whether the aircraft is moving in the same direction as the direction in which the control handle is extended as detected by the handle orientation detection mechanism. The engine stop device is configured to operate the engine stop device to stop the engine when the forward/reverse switching detection mechanism detects that the steering wheel is in the state and the grip state detection mechanism detects that the control handle is not gripped. At the same time, when the forward/reverse switching detection mechanism detects that the aircraft is moving in a direction opposite to the direction in which the control handle extends, the above-mentioned This is because the engine stop device is configured to be inactive.

The effects obtained by taking the above technical measures are as follows.

■ In other words, when the operator takes his hand off the handle only when the aircraft is moving backwards, the aircraft is configured to stop and for the safety of the operator, so when the aircraft is moving forward, the operator must keep the control handle in a constant position at all times. This eliminates the inconvenience of having to keep holding the handle, reduces operator fatigue, and provides an excellent walk-behind work vehicle in terms of practical ease of use, such as being able to perform other tasks at the same time. .

■ Furthermore, the above-mentioned method of stopping the aircraft only when moving backwards can reliably stop the aircraft and avoid danger to the operator, regardless of the direction of the steering wheel, as long as the aircraft is moving backwards relative to the operator's position. It is something.

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

A mission case 4 having a pair of left and right drive rotating shafts 3, 3 is attached to a machine frame 2 on which an engine 1 is mounted at the front, and a tilling rotary 5, 5 is attached to each of the rotating shafts 3, 3, and a A control handle 7 having a grip part 6 is extended to the rear of the machine body, thereby configuring a walking-type tillage vehicle in which the machine body travels while cultivating the ground by the two rotors 'J5, 5. .

A gear-type forward/reverse switching device (not shown) is provided in the mission case 4 for switching the drive direction of the two rotating shafts 3, 3 to the forward and backward directions of the aircraft, and for switching the drive speed in the forward and backward directions into two high and low steps. An operating mechanism 9 for the switching device is constructed as shown in FIG. 2, and includes an operating lever 8 that is installed inside the machine and extends to the rear of the aircraft body, so that the lever 8 is used to switch the aircraft forward or backward and change the traveling speed. That's how it is.

That is, the first sliding shaft 10 operates the switching device to drive both rotaries 5, 5 in the forward direction of the aircraft and to switch the driving speed from neutral to high and low;
A second sliding shaft 11 for operating the switching device is protruded from the mission case 4 in order to drive both rotaries 5, 5 in the backward direction of the aircraft and to switch the driving speed from neutral to high and low. It is set up.

On the other hand, the mission case 4 is provided with a member 12 held swingably around the axis X in the lateral direction of the aircraft body, and a sliding member 12 is provided with an arm 13 that selectively engages with both the sliding shafts 10 and 11. A moving shaft operating member 14 is held by the swinging member 12 so as to be swingable around the vertical axis Y, and the base end of the lever 8 is connected to the operating member 14.

In other words, when the lever 8 is swung around the horizontal axis X,
When the arm 13 is engaged with either one of the sliding shafts 10, 11 to select forward or backward movement, and the lever 8 in the engaged state is swung around the vertical axis Y. , the sliding shaft 10 or 11 engaged with the arm 13 can be operated to change gears.

The handle 7 is attached to the upper part of the mission case 4 so as to be rotatable and fixed in the longitudinal direction of the aircraft around the vertical axis 2, and the gear shift lever 8 is attachable to and detachable from the operating member 14, and is attached to the upper part of the mission case 4. It is attached so that the direction can be changed in the front and rear directions, so that the extending direction of the control handle 7 can be changed to the front of the aircraft by artificially rotating it, and the extending direction of the gear shift lever 8 can be changed by manually inserting and removing it. If the direction is changed to the front of the aircraft by the operation and the direction change operation, the aircraft can be driven with the mission case 4 on the front side of the aircraft, and the swinging operation of the lever 8 can switch between forward and backward movement and change the traveling speed. .

As shown in FIG. 2, a first switch 17 is provided which rotates integrally with the operating handle 7, and a cam 16 is brought into contact with or released from contact with the first switch 17 as the handle 7 is rotated. A handle orientation detection mechanism 20a is provided, which is configured by fixing the handle to the mission case 4, and as shown in FIGS. 2 and 3, a switch operating portion 10a is provided on the first sliding shaft 10 portion, When the first sliding shaft 10 is operated to the neutral position, it is operated to the open state by contacting with the operating portion 10a, and when the first sliding shaft 10 is operated to the low-knock drive position, the contact between the operating portion 10a and the operating portion 10a is opened. A second opening/closing switch 18 is provided which becomes open when the contact is released, and a switch operating portion 11a is further provided at the second sliding shaft 11 portion, and the second sliding shaft 11 is operated to a neutral position. and the operating portion 11a are brought into contact with each other and operated to the open state, and the second
A switching device operation state detection mechanism 20b is provided, which includes a third opening/closing switch 19 that releases contact with the operating portion 11a and enters a closed state when the sliding shaft 11 is operated to the rotary drive position. , a device 20 for detecting the extending direction of the handle 7 and the operating state of the transmission device.

That is, when the first switch 17 is suppressed by the cam 16, it is detected that the extending direction of the handle 7 is toward the rear of the aircraft, and when the first switch 17 is removed from the cam 16, the extending direction of the handle 7 is detected. It is detected that the aircraft is facing forward, and when the second switch 18 is open and the third switch 19 is closed, it is detected that the switching device is in an operating state to move the aircraft toward the mission case 4 side. However, if the second switch 18 is in the closed state and the third switch 19 is in the open state, the switching device detects that the aircraft is in the operating state to run toward the engine 1 side.

As shown in FIG. 1, the grip portion 6 is provided with a push-button fourth opening/closing switch 21 as a grip state detection mechanism. The handle 7 is configured to be maintained in the push operation state by the hand against the handle 7, and is also configured to detect that the handle 7 is in the non-grip state when the push operation is released and the handle 7 enters the closed state.

As shown in FIG. 4, when the first switch 17, the second open/close switch 18, the third open/close switch 19, and the fourth open/close switch 21 are energized, they are in an operating state in which the engine 1 is stopped. A control circuit 22 is interposed in the power supply circuit of the device 38 and is automatically operated based on information from the detection device 20 and the fourth opening/closing switch 21 regarding the handle extension direction and the operating state of the switching device. This is for the safety of workers.

That is, the first switch 17 has a normally open first switch part 17a that is closed by the pressure of the cam 16 when the handle 7 is extended toward the rear of the aircraft body, and is opened when the handle 7 is extended toward the front. A normally closed second switch portion 17b is provided, which opens when the handle extends toward the rear of the aircraft body and closes when the handle extends toward the front.

The first switch section 17a and the third opening/closing switch 19
and a second circuit 24 in which the second switch section 17b and the second open/close switch 18 are connected in series.
4 are placed in parallel and connected in series to a circuit in which the fourth on-off switch 21 is interposed.

Therefore, the first circuit 23 or the second circuit 24 is closed only when the switching device is operated to cause the body to travel in the extending direction of the handle 7, and only in that case, the fourth opening/closing When the switch 21 is closed, the entire short circuit is closed, the engine 1 is automatically stopped, and the rotaries 5, 5 are stopped from being driven.

The normally open switch 25 shown in the figure is closed when the engine is stopped to close the short circuit.

In other words, no matter which direction the handle 7 extends, when moving the aircraft backwards, the fourth opening/closing switch 2 is
Press 1 and operate while keeping it in the open state.

If it becomes impossible to move backwards due to a fall or the like, when you release your hand from the grip 6, you also release your hand from the fourth opening/closing switch 21.
2 is activated to stop the aircraft from moving backwards.

The forward/reverse switching device may be replaced with one that simply allows switching between forward and backward travel, and FIGS. 5 and 6 show the switching device operating mechanism 9 and switching device operating state detection mechanism in that case. 20b, and FIG. 7 shows the travel stop device 22 in that case, each of which is constructed as follows.

That is, the operating mechanism 9 is configured such that a sliding shaft 26 for operating the switching device is provided protruding from the transmission case 4, and is swingable around a vertical axis 11 whose one end is locked to the sliding shaft 26. A lever operating member 29 having an arm 28 latched to the other end of the sliding shaft operating lever 27 is provided to be slidable around the vertical axis 22. The proximal end portions are connected so that they can be separated and changed in direction.

In the figure, numeral 30 denotes a sliding shaft positioning mechanism, which is configured to act on an arm 31 protruding from the lever operating member 29.

That is, when the lever 8 is swung around the vertical axis 22, the lever 27, which oscillates around the vertical axis 11 via the arm 28, moves the sliding shaft 26 from the neutral position to the rotary forward drive position and backward movement. It is designed so that it can be switched to the drive position.

The detection mechanism 20b includes a switch operating arm 32 that swings together with the sliding shaft operating lever 27.
A snap switch 34 is provided in which a switch operation lever 33 is engaged, and the switch 34 is closed only when the switching device is in a forward operation state, that is, a state in which the aircraft is moved toward the engine 1 side. Contact A1
A contact B is provided that is closed only when the switching device is in a reverse operation state, that is, a state in which the aircraft is moved toward the mission case 4 side, and when the switching device is in a neutral state, both fluids A and B are in an open state. That's how it is.

In other words, the switch 34 is configured as a mechanism for detecting the operating state of the forward/reverse switching device.

The control circuit 22 includes a first circuit 23 connecting the first switch section 17a and the contact B;
The second circuit 24 connecting the second switch section 17b and the contact A is put into a parallel state and the fourth open/close switch 2
Connect to 1.

The operating handle 7, the handle direction detection mechanism 20a, the lever operation member 29, and the switching operation state detection mechanism 20b shown in FIGS. 5 and 6 are attached to the mission case 4 via the base member 35, and the The base member 35 is configured to be able to swing freely around the horizontal axis 36 with respect to the mission case 4 and to be swingably fixed by bolts 37.

In other words, the extension angle of the operating handle 7 can be changed by swinging the base member 35.

The fourth opening/closing switch 21 may be installed inside the grip 6, or may be replaced with a device that senses the grip force applied to the grip 6. In short, the fourth switch 21 can be used to detect the non-grip state of the handle 7. Any device may be used, and these devices are collectively referred to as a device 21 for detecting a non-grip state of the handle 7.

[Brief explanation of the drawing]

The drawings show an embodiment of the walking work vehicle according to the present invention.
The figure is an overall side view of the tilling vehicle, Figure 2 is a side view of the switching device operation mechanism, handle orientation detection mechanism, and switching device operation state detection mechanism, Figure 3 is a plan view of the switching device operation state detection mechanism, and Figure 4 is a side view of the switching device operation state detection mechanism. The figure is a schematic diagram of the travel stop device, FIG. 5 is a side view showing another aspect of the switching device operation mechanism and the switching device operation state detection mechanism, FIG. 6 is a view taken along the line Vl-Vl in FIG. 5, and FIG. FIG. 2 is a schematic diagram showing another embodiment of the travel stop device. 7...Handle, 20a...Handle orientation detection mechanism, 20b...Switching device operation state detection mechanism, 21...Grip state detection mechanism, 22...
... Control circuit, 38 ... Engine stop device.

Claims (1)

[Claims] 1. A walking work vehicle configured to allow the direction in which the control handle 7 extends to be freely changed back and forth and equipped with a forward/backward switching device, and to determine whether the direction in which the control handle 7 extends is on the side that is tilted back and forth. A steering wheel orientation detection mechanism 20a that detects, a switching device operation state detection mechanism 20b that detects whether the forward/reverse switching device is operated to tilt forward or backward, and a switching device operation state detection mechanism 20b that detects whether the steering wheel 7 is in a grasped state. A grasp state detection mechanism 21 for detecting whether the
In this case, the forward/reverse switching detection mechanism 20b detects that the aircraft is moving in the same direction as the extending direction of the control handle 7 detected by the handle orientation detection mechanism 20a, and the grip state detection mechanism 21 is the control handle 7
When the engine stop device 3 detects an uncontrolled state of the
8 and stops the engine 1, and the forward/reverse switching detection mechanism 20b detects that the aircraft is moving in a direction opposite to the direction in which the control handle 7 extends. Sometimes, the engine stop device 3
A walk-behind work vehicle characterized in that: 8 is configured to be inoperative.