JP2008290511A - Mower - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that performing an operation of a differential lock switching "ON" and "OFF" in a small ridable mower during a mowing operation instead of performing manually as in a conventional small ridable mower raises an inefficiency of the mowing operation due to the mowing operation being interrupted, and that an operator's continuance of the mowing operation with intention not to interrupt the mowing operation at any rate so that the operator can perform the operation of the differential lock causes the operator to be careless about steering operation due to the operation of the differential lock. <P>SOLUTION: The mower is configured so that an operation of a differential lock arm or differential lock shaft for operating a differential lock of a transmission "ON" and "OFF" is performed by an electric actuator such as a motor or cylinder. The mower is also configured so that a steering sensor is provided in a steering mechanism, and the actuator is operated to turn the differential lock "ON" when the steering wheel is at a position of an approximately straight traveling direction, and turn the differential lock "OFF" when the steering wheel is at other position. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention mainly relates to small riding among mowers or similar lawn mowers, and is a type in which a drive transmission with a differential lock mechanism is mounted, and relates to a driving operation method thereof.

In the past, most of the small-sized passenger mowers have been widely used in the four-wheel rear-wheel drive-front-wheel steering type. (Patent documents 1, 2) This is common as a drive control system. Further, since the mower mostly travels on rough terrain, a drive transmission that can lock the differential mechanism is generally used in order to stabilize the straight traveling performance.
Japanese Utility Model 06-55320 JP 2003-320864 A JP-A-5-16689

Diff lock “on” and “cut” are conventionally operated by operating the differential lock arm of the transmission by operating the differential lock lever in the lever operation panel that is mainly arranged in the vicinity of the seat. "Was. (Reference figure-Patent Document 2) When it is necessary to improve the straight-line stability by setting the diff lock to “enter”, not only during movement, but in the case of reciprocating alignment mowing work when the work area is wide, uneven projections, etc. This function is particularly necessary in the case of severe rough terrain work surfaces, and in continuous mowing work when the vehicle body is inclined, such as a river bank slope. When the diff lock lever operation to “turn on” or “cut” the diff lock is performed during the mowing operation, the operation is interrupted. There was also a risk that the steering operation would be inadvertent due to attention being paid to the operation of the diff lock lever, trying to do the work while not interrupting the work even a little. Some other agricultural machines of the same type have this differential lock lever on the side of the steering handle to improve operability. (Patent Document 3)
However, as long as the lever is operated, the work is inevitably interrupted, and both the inconvenience and inefficiency remain. The present invention provides a mowing machine that solves and releases the troublesome operation of the lever to “turn on” and “cut” the diff lock, improves the operability, and excels in the stability, safety, and workability of the mowing machine.

The means taken in the present invention to solve the above-mentioned problems is that the operation of the differential lock arm or differential lock shaft for “on” and “off” the differential lock of the transmission is performed by an electric actuator such as a motor or a cylinder. is there. Furthermore, a steering sensor is provided in the steering mechanism, and when the steering wheel is in a substantially straight traveling direction position, the actuator is operated to turn on the diff lock, and when it is in any other position, the diff lock is turned off. It is a configuration. Furthermore, one or more switches or levers are provided on the operation control panel, and by operating the switches or levers, the differential lock "automatic" on "and" off "operation mode" linked to the steering operation position and the differential lock "forced" This is a configuration in which the operation mode “ON” operation mode can be selected.

  The present invention has the following effects by applying the above means.

  In normal work, the diff lock is automatically “entered” and “cut” according to the steering position, so that the troublesome operation of the conventional diff lock lever is eliminated and the mowing work efficiency is improved.

  In normal operations, the diff lock is automatically “entered” and “cut” depending on the steering position, so it is suitable for rough terrain and rough surfaces with lots of unevenness in Japan. An excellent mower can be realized.

In addition to the normal automatic mode, the forced mode is also provided, so that the stable traveling work area is expanded and the mowing work efficiency is improved.

By setting the steering sensor so that the play angle of the steering wheel + the forward straight traveling direction angle, the steering feeling becomes smooth without a sense of incongruity.

  A first embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a left side view of an embodiment of the mower of the present invention, FIG. 2 is a plan view showing a differential lock operating mechanism of the mower of the present invention, FIG. 3 is a diagram showing an actuator mechanism, and FIG. 4 is a diagram showing a steering sensor mechanism. The illustration is partially omitted for clarity. The mower can receive the rotational output of the engine 2 from the engine pulley 21 by the cutting blade pulley 12 and rotate the cutting blade 11 to mow the grass. The cutting height can be set by the lifting lever 13. On the other hand, it is received by the transmission pulley 31 separately from the engine pulley 21, driven by the traveling drive wheel 6 through the transmission 3, and the front wheel 5 is steered and operated by operating the steering wheel 41.

  The linkage structure of the steering system 4 of the mower of the present invention and the differential lock arm 32 of the transmission 3 will be described. The diff lock is “entered” by pulling and rotating the diff lock arm 32 of the transmission 3 in the wire direction of FIG. 2. If the wire is returned, it will be “cut” with the built-in springback. Conventionally, this wire (or rod) operation is manually performed with a lever. The mowing machine of the present invention realizes the electrification of this and has made a great progress. The steering system 4 is provided with a steering sensor 44 for detecting the moving position of the rack on the general configuration of the steering wheel 41, the steering shaft 42, and the rack and pinion unit 43, and the motor control unit is adapted to the operation of this sensor. The electric power of the battery 7 is fed through the harness 8 to the motor & wire unit 46, which is an electric actuator 45. The motor & wire unit 46 “pulls” and “returns” the differential lock wire 47 connected to the differential lock arm 32 to “enter” and “cut” the differential lock.

  The motor & wire unit 46 which is an electric actuator of the mower of the present invention will be described. The upper two of FIG. 3 are two views. The unit 46 mainly includes a motor 461, a reduction gear pair 462 and 463, a cam plate 464, a limit switch pair 466 and 467, and the like, and one end of a diff lock wire 47 is pivotally supported on a support shaft 465 fixed to the cam plate 464. Yes. The motor 461 rotates forward and backward, but the corner portion of the cam plate 464 fixed to the shaft of the reduction gear 463 is configured to stop at the moment when the limit switch 466 or 467 is operated. Rotate between limit switches 466 and 467 in the direction. The differential lock wire 47 is “pulled” and “returned” by the rotation of the cam plate 464. The center diagram is a diagram in which the cam plate 464 is rotated in the clockwise direction and the limit switch 466 is operated, and the wire 47 is stopped in the “return” state. On the other hand, the lower figure is a figure stopped in the “pulling” state of the wire 47 at the position where the limit switch 467 is operated by rotating counterclockwise.

  The steering sensor 44 and the related configuration of the mower according to the present invention will be described with reference to FIG. The steering mechanism mainly includes a steering wheel 41, a steering shaft 42, and a rack and pinion unit 43. In conjunction with the rotation of the steering wheel 41, the rack in the rack and pinion unit 43 linearly moves in the horizontal direction in the figure. Along with this operation, the tie rod connected to the rack bracket 431 fixed to the left and right ends of the rack is pushed and pulled to rotate the knuckle arm of the wheel hub to perform steering. This is the very basic configuration of a rack and pinion type steering mechanism. The steering sensor 44 detects the left / right linear operation position instead of detecting the rotation angle of the steering wheel 41, and includes a limit switch 441, a switch bracket 442, a sensor guide 443, and the like. The limit switch 441 is a roller type contact portion and is fixed to the machine body by a bracket 442 (not shown). The sensor guide 443 is fixed to the left and right ends of the rack together with the rack bracket 431, and moves linearly in the left-right direction in the drawing in conjunction with the rotation of the steering wheel 41. A contact surface with the switch 441 is provided to detect the operation position of the rack. A plan view of the contact surface of the sensor guide 443 with the switch 441 is shown below. The roller contact portion of the limit switch 441 traces on the A line in the range B in conjunction with the rotation of the steering wheel 41. The contact surface of the guide 443 is provided with a pair of left and right contact adjustment plates 444L and 444R so as to be adjustable this time. If the roller contact portion of the limit switch 441 is in contact with the contact adjusting plate 444, it can be detected that the vehicle is turning, and if it is in the gap and is in the non-contact state, it is detected that the vehicle is running substantially straight.

  With the above two control elements, it is possible to enter the diff lock “ON” state during the substantially straight-ahead maneuvering, and “OFF” state during the turning maneuver. The control block and other component configurations are shown in FIGS. Normally, when the switch 1/48 is turned on, the motor & wire unit 46 is driven by the motor control unit 45 in conjunction with the turning on / off of the steering sensor 44, and the differential lock is turned on / off. In addition, switches 2.49 are provided especially when a forced differential lock is required. When this is turned on, the diff lock is “on” regardless of whether the steering sensor 44 is on or off. The motor control unit 45 is mounted in the front bonnet. The other units in the bonnet are for control other than this system. The switches 1 and 48 and the switches 2 and 49 are arranged on the steering panel below the steering wheel 41 so as to be easy to operate. Other switches are for control other than this system.

In the embodiment, a motor is used as the actuator, but a linear motion actuator such as a cylinder may be used. Alternatively, a wire may be used to rotate the differential lock arm 32, but a rod may be used. Further, the shaft of the diff lock arm 32 can be directly rotated by an actuator. The embodiment succeeds in electrification without greatly changing the conventional structure of the airframe.

  It can be used for all small and medium-sized riding work machines such as small and medium-sized agricultural machines and civil engineering machines that use a drive transmission with a differential lock mechanism.

It is a left view of the mowing machine which shows this 1st Example. It is a top view which shows the electric operation system of the diff lock | rock of this 1st Example mower. It is detail drawing of the electric actuator which performs the electric operation of the differential lock | rock of this 1st Example mowing machine. It is a figure which shows the steering sensor part in connection with the electric operation control of the differential lock | rock of this 1st Example mowing machine. It is a block diagram which shows the electric diff lock control of this 1st Example mower. It is a front view which shows the mounting state of the control unit in connection with the electric operation control of the differential lock | rock of this 1st Example mowing machine. It is a perspective view which shows arrangement | positioning of the operating devices in connection with the electric operation control of the differential lock | rock of this 1st Example mowing machine.

Explanation of symbols

1 Mowing unit 2 Engine 3 Drive transmission (with differential lock mechanism)
4 Steering 5 Front wheel 6 Driving rear wheel 7 Battery 8 Wire harness 11 Cutting blade 12 Cutting blade pulley 13 Lift lever 21 Engine pulley 31 Transmission input pulley 41 Steering wheel 42 Steering shaft 43 Rack & pinion unit 44 Steering sensor 45 Motor control unit 46 Motor & wire unit 47 Differential lock wire 48 Switch 1
49 Switch 2

Claims (3)

  A small riding mower using a pair of left and right steering front wheels, a driving rear wheel or driving front wheel or driving front and rear wheels, and a cutting portion between the front and rear wheels, and using a transmission with a diff lock mechanism as a driving transmission mechanism for the driving wheels. A small-sized riding mower configured to operate a differential lock arm or differential lock shaft for “entering” and “cutting” a differential lock of the transmission with an electric actuator such as a motor or a cylinder.   In a small riding mower that steers using a steering wheel or steering handle, a steering sensor is provided in the steering mechanism. 2. The small riding mower according to claim 1, wherein the differential lock is configured to be “cut” when in the other position.   One or more switches or levers are arranged on the driving operation panel, and by operating the switches or levers, the diff lock “automatic“ on ”and“ off ”operation mode” linked to the steering operation position and the diff lock “forced” on The small riding mower according to claim 1 or 2, wherein an operation mode of "operation mode" can be selected.

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