JP2622196B2 - Work vehicle swivel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a descending state in which a traveling apparatus of a plurality of traveling apparatuses, which is located on the turning center side, descends so as to float, and an ascending state in which the traveling apparatus rises so as to contact the ground. The vehicle body is provided with an up-and-down type grounding body that is capable of ascending and descending and forming the turning center in the descending state, and at least the grounding portion of the up-and-down type grounding body is arranged around the longitudinal axis with respect to the vehicle body. The present invention relates to a turning device for a working vehicle, which is configured to be rotatable and provided with control means for controlling the traveling device to turn the vehicle body in the lowered state.

[0002]

2. Description of the Related Art The turning device for a working vehicle as described above is used, for example, for automatically performing operations such as lawn mowing and cleaning. In other words, it is used, for example, when the work vehicle is turned to move the work vehicle to the next adjacent work process when performing a so-called reciprocating run that repeats traveling from one end side to the other end side of the work place. . As described above, when the work is performed automatically, a geomagnetic sensor is generally provided to detect the direction of the work process. Then, the work vehicle is turned by obtaining the turning angle of the vehicle body based on the detection information of the geomagnetic sensor. Incidentally, since the geomagnetic sensor is affected by residual magnetism of the vehicle body, the relationship between the turning angle of the vehicle body and the detection information of the geomagnetic sensor is not always linear. Therefore, conventionally, for example, correction data of the turning angle of the vehicle body with respect to the detection information of the geomagnetic sensor is set and stored in advance, and the turning angle of the vehicle body is obtained by referring to the correction data.

[0003]

The residual magnetism of the vehicle body is not always kept constant, and may change both in quantity and direction. Therefore, in the above-described conventional technology, the detection of the turning angle of the vehicle body becomes inaccurate, for example, when the residual magnetism of the vehicle body changes, and the turning angle of the vehicle body becomes a value different from the target angle, so that the proper turning travel can be performed. There was no fear. SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned conventional drawbacks and to provide a turning device for a working vehicle capable of accurately detecting a turning angle of a vehicle body and appropriately turning the vehicle body.

[0004]

In order to achieve this object, a turning device for a working vehicle according to the present invention is characterized in that an angle detecting means for detecting a rotation angle of the ground contact portion with respect to the vehicle body is provided, The means is configured to control the traveling device in the descending state to turn the vehicle body at a target angle based on the detection information of the angle detecting means with the grounding portion as a turning center.

[0005]

When the vehicle body is turned, the up-and-down type grounding body is set in a lowered state, and the angle of rotation with respect to the vehicle body is detected by the angle detecting means at that time as a reference angle. The difference between the rotation angle with respect to the vehicle body detected by the angle detection means and the reference angle is equal to the target angle (for example, 180 in the case of reversal).
It is sufficient to control the traveling device until it coincides with (degree).

[0006]

Therefore, as compared with the conventional case using a geomagnetic sensor, the turning angle of the vehicle body can be accurately detected irrespective of the area or surrounding environment, and the operation of turning the target angle can be performed properly. Therefore, even when the operation is performed automatically, the reliability of the operation can be improved.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a small lawn mowing work vehicle will be described below with reference to the drawings.
As shown in FIGS. 5 and 6, a single front wheel 1F for steering is attached to the front of the vehicle body V, and a pair of left and right driving rear wheels 1L, 1R is attached to the rear of the vehicle body V. .

A rotary blade 2 for lawn mowing, which is rotationally driven by an engine E, is attached to a substantially central lower portion of the vehicle body V. Although not described in detail, the engine E drives a pair of left and right driving rear wheels 1L and 1R via a driving case 3. Also, the pair of left and right driving rear wheels 1
The left and right L, 1R are not provided with a differential device and are driven to rotate left and right simultaneously.

At the front of the vehicle body V, three copying sensors S1, S2, S3 for detecting the presence or absence of uncut grass are mounted in a state of being lined up in the width direction of the machine body. However, the sensors S1 and S3 at the left and right ends are located behind the front wheel 1F, and the sensor S2 at the center is located ahead of the front wheel 1F. If the scanning sensors S1, S2, and S3 are further described, they are configured as a so-called photo-interrupter type, and light transmitted between a light source and a light receiver, which are disposed to face each other at an interval in the left-right direction, is not used. It is possible to determine whether the location where the sensor is attached is the uncut area A or the already-cut area B based on whether or not the grass is cut off by the uncut grass. The three sensors are arranged in the vehicle width direction in order to automatically travel along the boundary L between the uncut area A and the already-cut area B (see FIG. 7). This is because it is possible to determine whether the end of the work process has been reached when determining whether the vehicle has shifted in the direction or when the vehicle body V is automatically driven. At the rear of the vehicle body V, a geomagnetic sensor S0 is attached.

[0010] As shown in FIG. 7, the lawn mowing vehicle described above has an uncut area A surrounded by a cut area B, and a boundary between the uncut area A and the cut area B. Along L
By traveling from one end to the other end of the work place, turning to the uncut side as it reaches the end, and reversing the next work step adjacent to it, repeating so-called reciprocating travel It is configured to automatically perform a lawn mowing operation in a predetermined range. By the way, the boundary L is basically a straight line, and the angle formed by the straight line with the direction J of the geomagnetism is the reference azimuth θs of the traveling of the work vehicle (hereinafter, the angle is assumed to be clockwise positive). When the vehicle travels from one end of the working range to the other end along the boundary L between the uncut area A and the cut area B and reaches the end of the working area, the surrounding area becomes the cut area B. Therefore, all of the three copying sensors S1, S2, and S3 detect the cut ground B. Therefore, when all of the three copying sensors S1, S2, and S3 detect the cut ground B, it is determined that the end of one work stroke has been reached, and the uncut portion is moved to move to the next adjacent work stroke. It turns to the ground side. At this time, the work vehicle is turned so that the direction of the work vehicle becomes the reference azimuth angle θs.
It should be noted that the reference azimuth θs when turning is naturally inverted by 180 degrees.

By the way, when the vehicle reaches the end of the work stroke and turns toward the next work stroke, the drive rear wheel on the turning center side is lifted and only the drive rear wheel on the outside of the turn is turned in a state of contacting the ground. It is like that. That is, the pair of left and right driven rear wheels 1L, 1R corresponds to the traveling device.
In addition, as shown in FIGS. 3 and 4, a lowering state in which the rear wheel located on the turning center side is lowered to the inside of the body of the pair of left and right driving rear wheels 1 </ b> L and 1 </ b> R,
Thereafter, a pair of up-and-down type grounding members 4 that form a turning center in the descending state can swing up and down around the fulcrums P1 and P2 so as to swing freely around the fulcrum P1 and P2, respectively. Installed. A spring 5 for urging each of the pair of lifting and lowering members 4 to a raised state, and a rotary cam 6 for selecting one of the pair of lifting and lowering members 4 and switching to a lowered state are provided. ing. By the way, the cam 6 is connected to the motor 8 via the gear 7 and is rotated in one direction. Each time the cam 6 rotates by 90 degrees, both of the pair of up-and-down type grounding bodies 4 are in the up state ( 3) and a state in which one of the lifting / lowering type grounding bodies 4 is in a descending state and the other is in an ascending state (see FIG. 4). Further, the lifting / lowering type grounding body 4 which is in the lowering state every time it rotates by 180 degrees is configured to alternate. In addition, four proximity switches S4 for detecting the rotation angle of the gear 7 are provided on the same circumference, and a long hole is formed in a part of the circumference of the gear 7. Then, the proximity switch S4
Is configured to be OFF in a state facing the long hole and ON in other states. Therefore, cam 6 is 9
The rotation of 0 degrees can be detected. Also, an encoder 1 as an angle detecting means for detecting a rotation angle of the grounding portion 9 with respect to the vertical grounding member 4 is attached to the tip of the vertical grounding member 4 so as to be rotatable about a vertical axis.
6 are provided. An inclined surface R is formed on the outer side of the rear driving wheels 1L, 1R so that the ground contact area of the rear driving wheels 1L, 1R during turning is relatively large.

Next, a control structure for turning the vehicle body V will be described. As shown in FIG. 1, a control device H is provided using a microcomputer, and the control device H includes a geomagnetic sensor S0 and an encoder 16 as shown in FIG. , And the proximity switch S4 are connected. And the control device H
Is based on preset information and various input information,
The operation of the motor 8 and the transmission 3 is controlled. That is, the control unit 100 is configured using the control device H.

Next, the turning of the vehicle body V will be described with reference to the flowchart shown in FIG. First, when the end of the work stroke is reached, the traveling is stopped, and
It is rotated by one degree so as to be a reference of the turning of the lifting and lowering body 4, that is, a state in which the turning center side is in a down state and the other is in an ascending state. Next, the current azimuth angle θn is obtained from the detection information of the geomagnetic sensor S0, and the deviation Δθ from the reference azimuth angle θs is obtained.
Ask for. Then, after steering the front wheel 1F in the direction along the tangent of the circle formed when turning, the rear wheel 1F
L. 1R is driven forward, and turns based on the detection information of the encoder 16 until the reference azimuth θs is inverted, that is, until the rotation angle reaches the target angle of 180 degrees. Here, the output of the geomagnetic sensor S0 is measured, and the output value Vs of the geomagnetic sensor S0 at this time is set as a value corresponding to the reference azimuth angle θs. That is, during the lawn mowing operation, the vehicle travels based on the direction in which the output of the geomagnetic sensor S0 becomes the output value Vs. When the turning is completed, the cam 6 is moved to 9
By rotating by 0 degrees, both the pair of lifting and lowering type grounding bodies 4 are brought into a state of rising. Further, the front wheels 1F are directed straight. Thus, the turning operation is completed and the next traveling can be started.

[Alternative Embodiment] In the above embodiment, the deviation .DELTA..theta. Between the current azimuth .theta.n and the reference azimuth .theta.s is determined by the geomagnetic sensor S0, and the turning angle is changed according to the deviation .DELTA..theta. The angle may always be 180 degrees.
Further, in this case, the single-turn rotary potentiometer may be configured to rotate 360 degrees each time the vehicle rotates 180 degrees, and the specific configuration of the angle detecting means may be variously changed. In the above embodiment, the vehicle is driven forward when turning, but may be driven backward. In the above-described embodiment, the case where the present invention is applied to a lawnmower is shown, but the present invention can be applied to various work vehicles such as a cleaning vehicle. In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration shown in the attached drawings.

[Brief description of the drawings]

FIG. 1 is a block diagram of a control configuration.

FIG. 2 is a flowchart of a control operation;

FIG. 3 is a rear view of the lifting type grounding body.

FIG. 4 is a rear view of the lifting type grounding body.

FIG. 5 is a schematic plan view of a vehicle body.

FIG. 6 is a schematic side view of a vehicle body.

FIG. 7 is an explanatory view of a working mode.

[Explanation of symbols]

 1L, 1R Traveling device 4 Elevating type grounding body 9 Grounding part 16 Angle detecting means 100 Control means V Body

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location G01V 3/26 G01V 3/26 (72) Inventor Hiroshi Suzuki 64 Ishizukitamachi, Sakai-shi, Osaka Co., Ltd. Kubota Sakai Works (72) Inventor Katsumi Ito 64 Ishizu-Kitamachi, Sakai City, Osaka Prefecture Kubota Sakai Works Co., Ltd. 72) Inventor Kazuo Uchikoshi 64 Ishizukita-cho, Sakai City, Osaka Prefecture Inside Kubota Sakai Works (56) References JP-A-2-229330 (JP, A) JP-A-55-28184 (JP, A) 1962-12587 (JP, U)

Claims (1)

(57) [Claims] 1. A traveling device (1L), (1R) located on a turning center side of a plurality of traveling devices (1L), (1R).
A lifting type that can freely move up and down between a descending state in which the vehicle descends so as to float and an ascending state in which the traveling devices (1L) and (1R) ascend to ground, and forms the turning center in the descending state. A grounding body (4) is provided on a vehicle body (V), and at least a grounding portion (9) of the lifting / lowering type grounding body (4) is rotatable around a vertical axis with respect to the vehicle body (V). And control means (10) for controlling the traveling devices (1L) and (1R) to turn the vehicle body in the lowered state.
0), a turning device for a work vehicle, provided with angle detection means (16) for detecting a rotation angle of the ground contacting portion (9) with respect to the vehicle body (V), and the control means (100). Is based on the detection information of the angle detecting means (16) in the descending state, with the grounding portion (9) as the turning center.
A turning device for a working vehicle configured to control the traveling devices (1L) and (1R) to turn the vehicle body (V) at a target angle .