JP2002078411A - Mower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure protection and safety of a HST because when an mowing is carried out at a higher speed than usual in a small-sized mower, a power system of the HST becomes overload and the moving becomes dangerous. SOLUTION: This mower is constituted so that when a mowing operation crutch is in on-state, a sub-transmission may not be in a mode of the high-speed side for traveling, and in the reverse, when the sub transmission is at high-speed side, the mowing operation crutch may not be in the on-state, to prohibit concurrent movements.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work safety of a low-mount type or a mid-mount type of a lawn mower or a lawn mower, and to a protection device related to a power transmission device. is there.

[0002]

2. Description of the Related Art A small work machine such as a mowing machine uses an engine as a prime mover, uses an HST (hydraulic continuously variable transmission) as a main transmission, and switches a traveling speed between a high speed mode for movement and a low speed mode for work. A typical configuration uses a machine (gear transmission).

[0003]

However, in the case of a small-sized machine, there has been a problem that the power balance cannot be set with sufficient margin in order to reduce the size and weight and to reduce the cost. In other words, since the mowing work state and the self-propelled moving state are designed on the assumption that they are completely different modes in the normal use state, if the worker mistakenly or forcibly performs the mowing work at the moving speed (high speed), it is over- There is a problem that the load becomes a load and the HST of the power system, particularly the HST of the main transmission, is broken. In addition, it can be said that the operation is performed in a mode that is not in the normal operation method in terms of the working environment, and therefore, it is in a very dangerous state.

[0004] Therefore, the present invention aims at overcoming the above-mentioned drawbacks of the prior art and mainly for protecting the HST of the power system and improving the work safety.

[0005]

The technical measures taken in the present invention to solve the above-mentioned problems include a "high speed" mode for moving the sub-transmission when the mowing work clutch is in the "engaged" state. Or, conversely, when the auxiliary transmission is on the "high speed" side, the parallel operation is prohibited so as not to put the mowing work clutch in the "engaged" state.

[0006]

As a result, regardless of the immature, inexperienced, or aggressiveness of the worker, it must not exist originally.
The mowing work is performed at the moving speed (high speed).
In particular, failures due to overloading of the HST have been dramatically reduced. In addition, by making it impossible to perform a driving operation that is not in the normal operation method, work safety has been dramatically improved.

[0007]

An embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a side view showing an embodiment of the present invention in a low-mount type small riding mower. FIG. 2 is a plan view. The figure is partially omitted for easy viewing. The engine 3, which is a prime mover, has an output shaft mounted in a machine hanging direction. The input shaft of the transmission 4 is belt-driven from the output shaft and travels by traveling wheels 5,5. The steering of the vehicle body is performed by the steering wheels 6, 6 driven by the steering 7.

The transmission 4 includes a gear type auxiliary transmission section 4a and an HS
T section (hydraulic type continuously variable transmission) 4b, and by operating the sub-transmission lever 12, the sub-transmission arm 4c is rotated via the switching rod 12c, so that the mowing work speed (low speed)
And speed for movement (high speed). In addition, by rotating the HST adjusting arm 4d in the same manner by operating the HST lever 13, forward and backward and stepless speed setting can be performed. The above-mentioned levers are centrally arranged on the traveling panel 16 so that they can be operated efficiently. In addition, the panel is provided with an engine throttle lever and a differential lock lever. (Not shown) and sub-shift lever 1
The speed change lever switch 22 is mounted so as to be interlocked with the operation 2.

On the other hand, the engine output shaft drives the driven pulley 1b, which is disposed above the cutting unit 1, by a belt, and cuts the grass by rotating a disk-shaped cutting blade 1a connected to the pulley. Can pay. The mowing unit 1 is suspended substantially at the center of the body frame 2, and is moved up and down by operating the elevating lever 14 on the elevating panel 15 to adjust the position of the mowing height. The clutch mechanism for "entering" and "disconnecting" the working power of the mowing unit 1 is a belt tension type in which a tension pulley 11e is pressed against a belt, and is operated by a clutch lever 11. A clutch lever 11 is mounted on the clutch lever bracket 11b on which the clutch lever 11 is mounted.
The clutch lever switch 21 is mounted so as to be interlocked with the operation.

A configuration for inhibiting the parallel operation of the work clutch and the auxiliary transmission will be described. FIG. 3 is a plan view showing a clutch lever mechanism, and FIG. 4 is a side view thereof. FIG. 5 is a side view showing a sub-transmission lever mechanism portion. Clutch lever 1
1 is rotatably supported on a support shaft 11f on a clutch lever bracket 11b fixed to the body frame 2.
When the clutch lever 11 is depressed forward in the traveling direction, the clutch is "engaged". At this time, the wire bracket 11a fixed to the clutch lever 11 pushes the clutch pulley 11c against the driving pulley via a tension spring or the like (FIG. 2). On the other hand, when the clutch lever 11 is pulled up and is in a substantially vertical state, the clutch is "disengaged".

The clutch lever switch 21 is set to the clutch "disengaged" so as to interlock with the operation of the clutch lever 11.
In this state, when the clutch lever 11 is in a substantially vertical state, the switch head is pressed by the edge of the wire bracket 11b and the switch is turned on to be adjusted and fixed to the clutch lever bracket 11b. The switch is set to off when the clutch is "on" and on when the clutch is "off". 3 and 4 show the state of the clutch lever 11 and the state of the clutch lever switch 21 when the clutch is "on" and "off," respectively.

On the other hand, the auxiliary transmission lever 12 is
Is rotatably supported by a sub-shift lever bracket 12a fixed to the support shaft 12d. When the sub-shift lever 12 is tilted forward in the traveling direction, it is a moving speed (high speed) state.
At this time, the rod bracket 12b rotatably engaged with the auxiliary transmission lever 12 pushes the switching rod 12c to set the switching arm 4c of the auxiliary transmission 4a to the high speed side.
(FIG. 2). On the other hand, when the auxiliary speed change lever 12d is pulled up in the opposite direction, it is a working speed (low speed) state.

When the shift lever switch 22 is in the auxiliary shift movement (high speed) mode, the switch head is pressed by the contact surface of the rod bracket 12b and the switch is turned on so that the switch is turned on in conjunction with the operation of the auxiliary shift lever 12. 2 and is fixed after position adjustment to a switch bracket 22a fixed to the switch bracket 22. The switch is set to on when the sub-shift mode is "moving (high speed)" and to be off when it is "work (low speed)". FIG. 5 shows the state of the subtransmission lever 12 and the state of the transmission lever switch 22 in the subtransmission mode “for movement (high speed)”.

FIG. 6 shows a control block and a control sequence (logic). When the clutch lever switch 21 is turned off with the above two switches and the instantaneous speed change lever switch 22 is turned on, the engine stop code is body grounded by the controller 23 to stop the engine 3 so that the mowing work is not performed at a moving (high speed) speed. . Clutch lever switch 21
Is used "off" for circuit configuration reasons because the switch is also used for another engine start interlock function. This stopping method is a general method for an industrial small gasoline engine in which the primary side of the ignition coil is short-circuited and the plug is not ignited. The controller 23 is constituted by a seat position switch for detecting a worker's seating and a brake position switch for detecting "on" and "off" of the traveling brake, in addition to the above two switches, and is mounted under the hood. (Fig. 1, Fig. 2)

In this embodiment, the engine is stopped to protect the power system, especially the HST, by applying to a small riding mower. However, in a machine one size larger than this, the power system has room and the mowing work is performed in the moving mode. Some models do not immediately become overloaded. It is not necessary to stop the engine immediately, but there is a problem with the work for a long time, and the work will be continued in a dangerous state. In such a case, an alarm is issued to alert the worker. In the case of a diesel engine, the engine is stopped by driving the fuel cut solenoid instead of short-circuiting the engine stop code.

With the above configuration, a configuration in which the work clutch and the auxiliary transmission are inhibited from being electrically operated in parallel can be realized. The configuration is not limited to the switches shown in this embodiment.

[0017]

According to the present invention, an electric or mechanical parallel operation of the work clutch and the sub-transmission is prohibited in the riding small mower, and when the mowing work clutch is in the "on" state, the sub-transmission is moved. The following effects are achieved because the high-speed mode is not set, or conversely, when the auxiliary transmission is on the high-speed side, the parallel operation is prohibited so that the mowing work clutch is not set to the "on" state. Having.

[0018] Regardless of the operator, the body moving speed
The irregular use of the mowing operation at (high speed) can no longer be performed, and the failure of the power system, particularly the failure due to the overload of the HST, has been dramatically reduced.

Dangerous high-speed running work is no longer possible, and work safety has been dramatically improved.

[Brief description of the drawings]

FIG. 1 is a side perspective view of a low-mount small riding mower showing an embodiment of the present application.

FIG. 2 is a plan view of a low-mount type riding mower showing an embodiment of the present application.

FIG. 3 is a plan view showing a mowing work clutch lever portion.

FIG. 4 is a side view showing a mowing work clutch lever part.

FIG. 5 is a side view showing a sub-transmission lever portion.

FIG. 6 is a diagram showing a control block and a control sequence.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cutting part 2 Body frame 3 Engine 4 Transmission 5 Running wheel 6 Steering wheel 7 Steering 8 Seat 11 Work clutch lever 12 Subtransmission lever 13 HST lever 14 Elevating lever 21 Clutch lever switch 22 Transmission lever switch 23 Controller

Claims (3)

[Claims] 1. A work clutch mechanism for turning on and off the power of a reaping unit, the operating device, and switching of the machine running speed between "moving (or high speed)" and "working (or low speed)". In a mower equipped with a sub-transmission and the operating device, the sub-transmission is not set to a "high-speed" mode when the work clutch is "on", or the first-stage work clutch is used when the sub-transmission is "high". A protection device for a mower, characterized in that a parallel operation that does not allow the user to “enter” is prohibited. 2. The system according to claim 1, wherein the parallel operation prohibition configuration is provided with a switch between the work clutch mechanism or the operating device and the auxiliary transmission or the operating device, and the operation clutch is set to “on” and the auxiliary transmission is set to the “high speed” side. 2. The protection device for a mower according to claim 1, wherein an alarm is issued in a circuit or an engine is stopped when the engine is stopped. 3. When the parallel operation prohibition configuration is set to the “engaged” state of the work clutch, the auxiliary transmission is not moved to the “high speed” side by a traction device engaged by a link or a wire, or the auxiliary transmission is 2. A mechanical (mechanical) parallel operation prohibition configuration in which the work clutch operating device is prevented from being brought into the clutch "engagement" side by a restraint device engaged by a link or a wire when the "high speed" side is engaged. A mower protector as described.