JP4289620B2 - Seating detection structure for work equipment - Google Patents

Description

  The present invention relates to a seating detection structure used for a working machine such as an agricultural tractor or a mower.

  In the above working machine, the engine cannot be started unless the driver is seated in the driver's seat, or the driver is not seated in the driver's seat while the engine is running for more than the set time. Then, there is one configured to perform engine stop control.

As a structure for detecting whether or not the driver seat is seated, a means for detecting the vertical displacement of the driver seat using a sensor such as a limit switch is generally used. As shown in the figure, the driver's seat is pivotally connected to the front end of the seat support member whose position can be adjusted back and forth so that the driver's seat can swing up and down. In the structure where the switch that faces the bottom of the seat is attached to the seat support member, when the driver is seated on the driver's seat, the switch is pressed to detect the seated state, and when the driver stands up or comes off the driver's seat, the seating load disappears. The seat is lifted slightly by the cushion spring, and the non-sitting state is detected by releasing the pressing operation of the switch.
Japanese Patent Laid-Open No. 11-5469

  The sensors in the above-described seating detection structure are generally arranged to be shifted to one side of the driver's seat due to wiring, maintenance, or the arrangement of the seat front-rear adjustment mechanism. Appropriate detection operation may be performed.

  That is, the worker sitting on the driver's seat often visually confirms the rear working portion depending on the work, and the driver worker turns the body while turning and turns around while sitting. In this case, the operator's weight acts on the driver seat in a lateral direction, whereby the driver seat is somewhat elastically distorted, and the side opposite to the side on which the body weight is unevenly floats and feels like a lift. Therefore, if the driving worker takes a long backward confirmation posture, there is a possibility that the sensor that is unevenly distributed in the lateral direction detects the rising of the driving seat and the engine stop control is executed.

  The present invention has been made paying attention to such points, and it is an object of the present invention to prevent misdetection of a non-sitting state even if the driver's seat is deformed in the left-right direction due to a bias in seating load.

The first invention is a seating detection structure of the working machine provided with a sensor for detecting the presence or absence of seating load acting vertically swingably supported driver seat seat as a vertical displacement of the driver's seat,
Wherein the driver's seat and driver's seat between the seat support frame which supports via a spring, e Bei long movable member in the lateral direction of displacement following the tilting of the lateral direction of the front SL driver's seat, the movable It said movable member in a horizontal side in the lateral direction and sets the lateral tilt can be supported fulcrum member, and attach the sensor to the other lateral side of the right and left direction of the movable member, the movable A cushion rubber that is in contact with the bottom surface of the driver seat in a state in which the driver seat tilts to one side in the left-right direction is attached to a position outside the fulcrum in the member in the left-right direction. To do.

  According to the above configuration, even if the driver seat tilts and deforms in the left-right direction due to the bias of the seating load, the movable member tilts following this deformation, so the relative positional relationship between the driver seat and the movable member does not change. The detection state of the sensor is maintained in the seating detection state.

  Therefore, according to 1st invention, even if a driver's seat deform | transforms into the left-right direction by the bias | inclination of seating load, it can avoid reliably misdetecting that it is a non-seating state.

According to a second invention , in the first invention, a fulcrum shaft is erected on an upper surface of a lateral side portion of the seat support frame in the left-right direction, and the movable member is laterally moved in the left-right direction. One side is externally supported, and the movable member can be tilted to the left and right by the interchange formed in the fitting portion between the movable member and the fulcrum shaft.

According to a third invention , in the second invention, a tongue piece erected on the upper side from the seat support frame is provided on the other lateral side portion in the left-right direction of the seat support frame, and is engaged with the tongue piece. The slit to be formed is formed on the other lateral side in the left-right direction of the movable member.

  FIG. 1 shows an agricultural tractor as an example of a working machine having a seating detection structure according to the present invention. This agricultural tractor has a cultivator specification in which a rotary cultivator 3 which is an example of a working device is connected to be movable up and down via a three-point link mechanism 2 hydraulically driven at the rear part of the four-wheel drive tractor main unit 1. It is configured.

  A driver's seat 5 is disposed between the left and right rear wheel fenders 4 at the rear portion of the tractor main body 1 so that the front and rear positions can be adjusted. Details of the mounting structure are shown in FIGS.

  Between the left and right rear wheel fenders 4, a sheet support 6 having a sheet metal structure covering the rear portion of the tractor main unit 1 is fixedly arranged, and a seat support base 7 is bolted and fixed to the upper surface of the seat support 6. A pair of front and rear suspension arms 8 are pivotally connected to the left and right outer surfaces of the seat support base 7, and a seat support 9 is pivotally connected in a parallel quadruple link shape across the upper ends of the suspension arms 8. The entire seat support 9 is supported by the swing of the suspension arm 8 so as to be movable in the vertical and forward / backward directions. A pair of left and right cushion springs (see FIG. 4) 10 is incorporated between the seat support base 7 and the seat support base 9, and the seat support base 9 is elastically biased upward by the cushion spring 10. Although the detailed structure is not shown, the tension of the cushion spring 10 can be adjusted by turning the handle 11 provided at the rear part of the seat support base 7, and the weight of the driver who is seated can be adjusted. Accordingly, it is possible to set a desired cushion characteristic.

  The seat support 9 is formed by bending a wide plate material and having a raised portion 9a at the left and right center, and a seat support frame is fixed to a slide rail 15 fixed on the upper surface of the left and right ends. 16 is mounted so that it can slide back and forth. The seat support frame 16 includes left and right slide portions 16a that are externally supported by the slide rail 15, a stay 16b that connects the front portions of the slide portions 16a, and a lateral fulcrum that is connected to the front end of the stay 16b. A boss 16c is provided, and the driver's seat 5 is mounted on the upper surface of the left and right seat mounting brackets 18 supported by the fulcrum boss 16c via the support shaft 17 so as to be swingable up and down. .

  A pair of levitation springs 19 and cushion rubbers 20 are mounted on the rear portions of the left and right slide portions 16a of the seat support frame 16, respectively. The levitation spring 19 is easily compressed and deformed by the seating load, and has elasticity that lifts and swings the empty driver's seat 5 when the seating load disappears. The cushion rubber 20 includes the levitation spring 19. The rear portion of the bottom surface of the driver seat 5 that has been compressed and deformed and rocked downward is elastically received.

  On the right side of the seat support frame 16, a lock fitting 21 for fixing the front / rear position of the slider can be rotated about the front / rear axis p through the operation support shaft 22, and can be rotated in the lock direction by a torsion spring 23. It is installed at once. Therefore, in the free state, the lock metal member 21 that is urged to rotate is engaged and locked with one of the notches n formed on the slide rail 15 at a predetermined pitch in the front-rear direction to prevent the driver seat 5 from moving back and forth. By pulling and turning upward the handle portion 22a that is bent and connected to the front end of the shaft 22, the lock fitting 21 is turned against the torsion spring 23 to release the engagement lock. Movement is allowed, and it is possible to adjust the movement back and forth to an arbitrary position.

  The driver seat support structure configured as described above is equipped with means for detecting whether or not the driver seat 5 is seated, and the detailed configuration thereof will be described below.

A horizontally long movable member 25 made of a belt-like plate material is mounted and supported at an intermediate position in the front and back of the seat support frame 16. The movable member 25 is externally supported by a fulcrum shaft 26 erected on the upper surface of the right slide portion 16 a of the seat support frame 16, and is fitted by appropriate flexibility formed at a fitting portion with the fulcrum shaft 26. The movable member 25 can be tilted to the right and left around the part. Further, the tongue 25d provided on the seat support frame 16 side is engaged with the slit 25b formed on the one end side of the movable member 25 so that the movable member 25 rotates in a plane around the fulcrum shaft 26. To be prevented. Further, the movable member 25 supported by the fulcrum shaft 26 unevenly distributed on the right side is tilted by its own weight in a direction in which the left end side is lowered, but the cushion rubber 28 fitted and fixed on the upper surface of the right end of the movable member 25 is provided on the driver seat 5. The movable member 25 is held in a posture parallel to the bottom surface of the driver seat 5 by coming into contact with the right side of the bottom surface.

  A sensor support portion 25a is continuously provided at the left end portion of the movable member 25, and a rotary operation type switch 29 as a seating detection sensor is mounted and connected thereto. A detection lever 30 that is urged to rotate upward is provided on the outer surface of the switch 29, and this detection lever 30 is pressed by an operation piece 18 a extending from the left rear end of the seat mounting bracket 18. It is like that.

  The seating detection structure is configured as described above, and when the driver is correctly seated on the driver's seat 5, the driver's seat 5 that receives the seating load is received and supported by the cushion rubber 20, as shown in FIG. The detection lever 30 is pushed down and turned to the ON position by the operation piece 18a, and the switch 29 detects the seating state. In this seating detection state, engine start is allowed.

  In a state where the driver is removed from the driver seat 5 and no seating load is applied, the driver seat 5 is lifted and swung by the levitation spring 19 as shown in FIG. 5, and the pressing operation by the detection piece 18a is released. The detection lever 30 is turned upward to the OFF position, and the switch 29 detects the non-sitting state. When this non-sitting state is detected, if the engine is stopped, the engine start is inhibited and when the non-sitting state is detected for a set short time during engine operation, the engine stop control is automatically performed. Made.

In addition, the seated driver is subjected to a seating load biased rightward on the driver's seat 5 by, for example, twisting the body to the opposite side of the switch, that is, the right side of the aircraft in this example, for the purpose of confirming the rear. Then, the driver seat 5 is twisted and deformed in the right downward direction. In this case, as shown in FIG. 6, when the driver seat 5 is deformed in the lower right direction , the movable member 25 is tilted following the tilt deformation of the seat bottom surface, and the left side of the movable member 25 is displaced upward. Accordingly, the switch 29 provided on the left side of the movable member 25 is also moved upward, so that the detection lever pressing operation state by the detection piece 18a is maintained, and even if the driver seat 5 is laterally deformed due to an unbalanced load, it is not seated. It is avoided that it is erroneously detected.

  [Other Examples]

(1) As the sensor 29 for detecting the vertical displacement of the driver's seat 5, a push-type switch, a proximity switch, or the like can be used in addition to the switch with a lever as described above.

Whole side view of agricultural tractor Side view showing the seating state of the driver seat support structure Top view of driver seat support structure Rear view of driver seat support structure Side view showing the non-sitting state of the driver seat support structure Rear view of the offset load acting state of the driver seat support structure

5 Driver's seat 16 Seat support frame
16d tongue
19 Spring 25 Movable member
25d slit
26 fulcrum shaft
28 cushion rubber 29 sensor

Claims (3)

A seating detection structure in the vertical swingably whether the seating load acting on supported driver seat's seat with a sensor for detecting a vertical displacement of the driver's seat working machine,
Wherein the driver's seat and driver's seat between the seat support frame which supports via a spring, e Bei long movable member in the lateral direction of displacement following the tilting of the lateral direction of the front SL driver's seat,
Wherein said movable member in a horizontal side of the left and right direction of the movable member sets the lateral tilt fulcrum which rotatably supports, the sensor Ri attached preparative beside the other side in the lateral direction of said movable member,
A cushion rubber that is in contact with the bottom surface of the driver seat in a state where the driver seat is tilted to one lateral side in the left-right direction is attached to a position outside the fulcrum in the movable member in the left-right direction. Features a seating detection structure for work equipment. A fulcrum shaft is erected on the upper surface of one lateral side in the left-right direction of the seat support frame, and the lateral one side in the left-right direction of the movable member is externally supported by this fulcrum shaft.
The seating detection structure for a working machine according to claim 1, wherein the movable member is configured to be tiltable left and right by the interchange formed at a fitting portion between the movable member and the fulcrum shaft. A tongue piece erected on the upper side from the seat support frame, provided on the other lateral side in the left-right direction of the seat support frame;
The seating detection structure for a working machine according to claim 2, wherein a slit that engages with the tongue piece is formed on a laterally lateral side portion of the movable member in a lateral direction.

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