JPH1120579A - Bumper device for moving objects - Google Patents

Abstract

(57) [Summary] [Problem] While fully utilizing a bumper's original buffering function, even if it contacts an obstacle, it can be reliably detected that the contact has occurred, and high security can be easily obtained. A bumper device for a mobile object. SOLUTION: As a mechanism for holding a bumper 12 on a main frame 2, four arms 13-1, 13-2, 13- are respectively connected by joints 13-5, 13-6.
A left switch 15 and a right switch, which perform switching operation by the movement of the arms 13-3 and 13-4, in addition to the obstacle sensor 14 attached to the bumper 12, using the joint link mechanism 13 constituted by 3, 3-4. 16 and provided. A coil spring is incorporated in each of the joints 13-5 and 13-6, so that the impact when the bumper 12 comes into contact with the obstacle O is absorbed by bending at the joint of the arm. When at least one of the left switch 15 and the right switch 16 is turned on or off due to a change in the angle of the arm, the traveling of the moving body is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bumper device for a moving object having an obstacle detecting function, and more particularly to a bumper device for a moving object running at a relatively low speed such as a self-propelled lawn mower.

[0002]

2. Description of the Related Art For a moving body that travels at a relatively low speed, such as a riding powered lawn mower, bumpers are mounted in front and rear of the traveling vehicle, thereby causing an impact when the vehicle comes into contact with an obstacle. It is customary to mitigate this.

In recent years, a sensor for detecting an obstacle is provided on the bumper to detect the contact of the bumper with the obstacle and to control the deceleration and the stop of the vehicle. In addition to the above, a bumper device has been proposed in which a shock absorbing effect due to deceleration and stop of a vehicle can be obtained, and an example thereof is disclosed in JP-A-60-113750.
JP-A-2-256540, JP-A-7-61302
And JP-A-8-194538.

[0004]

However, the above prior art does not take into account the fact that the bumper may come into contact with an obstacle in a variety of ways, and has a problem in the function of detecting contact with an obstacle. That is, the contact of the bumper with the obstacle is not always from the front of the bumper, but from the side.
Alternatively, there may be contact from behind, such as hooking during retreat, but in the related art, only contact from the front can be mainly detected, and therefore, a problem occurs in the contact detection function for obstacles.

SUMMARY OF THE INVENTION An object of the present invention is to make it possible to reliably detect contact with an obstacle and to easily obtain high security while making full use of the bumper's original buffering function. It is another object of the present invention to provide a bumper device for a mobile object.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a bumper device for a moving body having a buffering function and an obstacle detecting function, wherein an articulated link mechanism for attaching a bumper to a vehicle body is provided. And a left and right sensor means for independently detecting the angular displacement of the left and right arms of the articulated link mechanism, wherein the left and right sensor means are provided. By at least one of the above, when the angular displacement of the arm is detected, at least one of the deceleration control and the stop control of the moving body is executed.

[0007] The obstacle may come into contact with the bumper at any angle, but according to the articulated link mechanism, the angle of at least one arm of the left and right link mechanisms changes in any case. Therefore, by using left and right sensor means for independently detecting the angular displacement of the left and right arms of the articulated link mechanism, it is possible to always surely detect the contact of the obstacle.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a bumper device for a mobile object according to the present invention will be described in detail with reference to the illustrated embodiments. FIG. 1 is a side view showing an embodiment of a moving body to which the present invention is applied, and FIG. 2 is a plan view thereof.

In this embodiment, the present invention is applied to an engine-driven self-propelled lawn mower 1. In these figures, reference numeral 2 denotes a main frame constituting a vehicle body. 3, a front wheel 4 and a rear wheel 5 are provided on the lower side. 4S and 5
S denotes an axle, and a vehicle speed sensor (not shown) is attached to these axles to detect the vehicle speed based on the rotation speed of each wheel. Also, mainframe 2
The lawn mowing units 6 and 7 are attached to a lower part of the self-propelled lawn mower 1.

In this embodiment, a hydraulic drive system is used. For this reason, the engine 3 drives a hydraulic pump 8, and the wheels are driven by the hydraulic oil generated by the hydraulic pump 8 to perform steering. Self-propelled, lawn mowing unit 6,
7 is driven up and down and the cutter is driven, so that lawn mowing can be obtained. For this reason, the wheels, the steering system, and the lawn mowing unit are each provided with a hydraulic actuator or a hydraulic motor. .

An operator's seat 9 and a steering wheel 10 are provided on the main frame 2 so that
At the time of manned driving, an operator can get on and drive, and therefore, around the seat 9, an operation lever 11, an accelerator pedal, a brake pedal (not shown) and the like are arranged.

Thus, the hydraulic pump 8 is driven by the engine 3.
Is driven, the wheels 4, 5 are rotated by hydraulic motors attached to the respective wheels, and the lawn mowing unit 6,
The vertical movement of 7 is operated by a hydraulic cylinder, and the cutter is driven by a hydraulic motor. As a result, the operation as a self-propelled lawn mower is obtained as described above.

In this embodiment, manual operation and automatic operation can be selected. During automatic operation, steering and accelerator operation are performed by a hydraulic actuator. Therefore, the self-propelled lawn mower 1 according to this embodiment is equipped with the control device 20 and various sensors necessary for the autonomous automatic driving. Then, the posture measurement sensor detects the current posture of the vehicle body (roll angle and pitch angle with respect to the horizontal plane). Next, the gyro sensor detects the yaw angle of the vehicle body, and the steering angle sensor detects the steering angle of the steering to calculate the angle of the steered wheels. The vehicle speed sensor calculates the vehicle speed from the rotation speed of each wheel, and the travel control angle sensor detects the control angle of the accelerator actuator.

As will be described later, a sensor for recognizing an obstacle near the bumper, a switch for detecting that the bumper has touched the obstacle, and the like are also provided. The emergency stop is configured so that the control device 20 can control the lawn mower 1
Can be operated automatically by autonomous navigation, so that the lawn mower 1 can perform lawn mowing work without any person, and furthermore, the wireless device 21 can be used to remotely control lawn mowing work.

Next, a front bumper 12F and a rear bumper 12R are attached to the front and rear of the main frame 2 by joint link mechanisms 13F and 13R, respectively. Obstacle sensors 14F and 14R are attached to these bumpers 12F and 12R, respectively. Note that, here, the suffix F represents the front member, and R represents the rear member. In this embodiment, the front member and the rear member are partially different in size and shape. Only the basic configuration is the same, and therefore, these will be described below in common except for the subscript.

FIG. 3 shows details of the joint link mechanism 13. In this figure, both ends of the bumper 12 are omitted. In FIG. 3, 13-1 is a left front arm, 13-2 is a right front arm, 13-3 is a left rear arm,
3-4 is a right rear arm, 13-5 is a left joint, 13-6 is a right joint, 13-7 is a left front pivot support, 13-8 is a right front pivot support, and 13-9 is a left rear. Rotating shaft support, 13-10 is right rear rotating shaft support, 13-11 is left lever, and 13-
12 is a right lever. 15 is a left switch and 1
6 is a right switch.

First, the left front arm 13-1 and the left rear arm 1
3-3 is rotatably connected to each other by a common axis in a left joint 13-5. Similarly, the right front arm 13-2 and the right rear arm 13-4 are shared by the right joint 13-6. Are rotatably connected to each other. At this time, as is apparent from FIG. 1, the left front arm 13-1 and the right front arm 13
Each of the left rear arm 13-3 and the right rear arm 13-4 is composed of two upper and lower arms, and each of the joints 13-5 and 13-6. The left front arm 13-1 and the right front arm 13-2 are connected by shafts so as to sandwich them from above and below, respectively.

Next, the front end of the left front arm 13-1 is rotatably supported by the bumper 12 by a left front rotation shaft support 13-7. Similarly, the rear end of the left rear arm 13-3 is It is rotatably supported on the main frame 2 by a rear rotating shaft support 13-9. Similarly, the tip of the right front arm 13-2 is
Similarly, the right rear arm 13-4 is rotatably supported on the main frame 2 by the right rear pivot shaft support 13-10. It is freely supported.

As a result, the left front arm 13-1 and the left rear arm 13-3 can be bent around the left joint 13-5. Similarly, the right front arm 13-2 and the right rear arm 13-4 can be bent. Can be bent around the right joint 13-6, forming a well-known pantograph mechanism as a whole. The bumper 12 moves between a state shown in FIG. 3 and a state shown in FIG. Is held by the main frame 2 so that it can freely move back and forth with the buffer stroke.

Next, a coil spring is mounted on each of the joints 13-5 and 13-6, so that the left front arm 13-1, the left rear arm 13-3, and the right front arm 13
-2 and the right rear arm 13-4 are connected to each joint 13-
At 5 and 13-6, an elastic force in a direction in which the angle becomes larger is given.

As a result, as shown in FIG. 3, if an obstacle O comes into contact with the bumper 12 in the direction of arrow A and pushes the bumper 12, as shown in FIG.
By retreating the bumper 12, each joint 13-5, 13-6
The angle of the front and rear arms is narrowed against the elastic force of the coil spring mounted on the bumper, whereby the buffering function as the original function of the bumper can be obtained.

At this time, each of the joints 13-5 and 13-6 is provided with a stopper (not shown) for regulating the rotation angle, so that the angle formed by the front and rear arms at this portion can be controlled by an external force. When the bumper 12 is not applied, it is opened to the state shown in FIG. 3, and in this state, it is prevented from opening further, so that the bumper 12 protrudes from the main frame 2 when there is no obstacle. Is set to a predetermined value.

Next, the left lever 13-11 and the right lever 13
Reference numeral -12 functions to operate the left switch 15 and the right switch 16, and is attached to the left rear arm 13-3 and the right rear arm 13-4, respectively. As shown in FIG. 3 and FIG. 4, the right rear turning shaft support portion 13-10 moves together with the left rear arm 13-3 or the right rear arm 13-4.

At this time, both the left switch 15 and the right switch 16 are constituted by micro switches mounted on the main frame 2. Here, when these switches are operated as make contact type, the signal is detected when the contact is turned off from on, and when used as the break contact type, the signal is detected when the contact is turned on. Is detected.

When the joint link mechanism 13 is in the state shown in FIG. 3, that is, when the front and rear arms are fully opened and the bumper 12 is fully projected, the left lever 13-11 and the right lever 13 The tip of the switch 12 is in contact with the operating member of each of the switches 15 and 16 and pushing the switch. From this state, when the angle of the front and rear arms is reduced by a predetermined amount, the left lever 13-
11 and the tip of the right lever 13-12 are each switch 15,
It is separated from the sixteen working members.

As a result, each of the left switch 15 and the right switch 16 operates as a sensor means for independently detecting the angular displacement of the left rear arm and the right rear arm. It is connected to the control device 20. Then, the control device 20 controls the left switch 15
When at least one of the right switch 16 and the right switch 16 is switched from on to off (or from off to on), control to stop the running of the lawn mower 1 is executed.

An obstacle sensor 14 is mounted on the bumper 12, for example, a well-known sensor for detecting an approaching object by an ultrasonic system or a radar system. During automatic driving, when there is any obstacle on the traveling route, the obstacle sensor 14 detects the obstacle and stops the lawn mower 1 until the obstacle is removed. The output is also supplied to the control device 20.

Next, an operation of detecting an obstacle according to this embodiment will be described. First, if an obstacle O is present on the traveling path of the lawn mower 1, it is detected by the obstacle sensor 14, so that the lawn mower 1 is stopped by the control device 20, and as a result, Safety is ensured. Then, this obstacle sensor 1
If the detection failure of the obstacle 4 occurs, the obstacle comes into contact with the bumper 12 (the bumper 12F or the bumper 12R).

Then, as shown in FIG. 3, an obstacle O approaches from the front of the bumper 12 as shown by an arrow A,
Next, assuming that the bumper 12 is pushed a predetermined amount, the left switch 14 and the right switch 15 are switched from on to off (or off to on). Therefore, even in this case, since the lawn mower 1 is stopped by the control device 20, safety is reliably maintained.

Next, as shown by an arrow B in FIG. 5, the obstacle O comes into contact with the bumper 12 from an oblique side, and the bumper 1
2 is translated horizontally, the left rear arm 13
Since the angle of -3 does not change, the angle of the left lever 13-11 does not change, and therefore the left switch 15 does not switch.
However, even in this case, since the angle of the right rear arm 13-4 changes, the right lever 13-12 moves as shown by the arrow C,
Since the right switch 16 is switched, the control device 2
0 ensures that the lawn mower 1 is stopped. Therefore, even in this case, there is no problem in securing safety.

In FIG. 5, the obstacle O is indicated by an arrow B
As shown in the figure, the case where the contact is made from the left front is shown. However, when the contact is made from the right front, the left switch 15 is switched. Will not occur.

Next, it is assumed that the obstacle O is hooked by the bumper 12 as shown in FIG. In this case, the force indicated by arrow D acts on the right end of the bumper 12,
At this time, since the angle between the right front arm 13-2 and the right rear arm 13-4 does not increase any more, the bumper 12 is rotated counterclockwise around the right front rotation shaft support 13-8, and The part moves as indicated by arrow E.

As a result, although the angle of the right rear arm 13-4 does not change, the angle of the left rear arm 13-3 changes, so that the left lever 13-11 moves as shown by an arrow C ', and the left switch 15 is turned on. Since the switching is performed, the lawn mower 1 is reliably stopped by the control device 20. Therefore, even in this case, there is no problem in securing safety.

In FIG. 6, the obstacle O is indicated by an arrow D
As shown in the figure, the case where contact is made from the right rear is shown. However, when contact is made from the left rear, the right switch 16 is switched. Will not occur.

Therefore, according to this embodiment, the bumper 1
2, even if the obstacle O comes in contact in any state, the obstacle O can be reliably detected, and the lawn mower 1 can be emergency stopped.

In the above embodiment, the front bumper 12F and the rear bumper 12R are attached by the joint link mechanisms 13F and 13R, respectively. However, the bumper is supported by the joint link mechanism as in this embodiment. In addition to the ones, there are those using a slide mechanism. FIG.
Fig. 4 shows the difference in size between the structure of the bumper by the slide mechanism and the structure of the bumper by the joint link mechanism.

In the case of the bumper using the slide mechanism shown in FIG. 7A, the buffering stroke of the bumper 12 is taken by the expansion and contraction of the slide rod S and the slide cylinder T, so that the bumper has a length other than that necessary to take the stroke. In addition, the length of the portion for storing the slide bar S is required, so that the mounting dimension becomes longer, and the size of a moving body such as a lawn mower increases. On the other hand, FIG.
In the case of the articulated link mechanism shown in (1), since the stroke is taken by the refraction of the link L, almost no extra length is required. Therefore, according to the above embodiment, there is an advantage that the size can be reduced.

[0038]

According to the present invention, the contact of an obstacle can always be detected without fail irrespective of the contact mode of the obstacle, while the original buffering function of the bumper is sufficiently maintained. High bumper device can be easily provided. As a result, the safety of the moving object can always be reliably ensured.

[Brief description of the drawings]

FIG. 1 is a side view showing an example of a lawn mower to which an embodiment of a moving object bumper device according to the present invention is applied.

FIG. 2 is a plan view showing an example of a lawn mower to which an embodiment of a bumper device for a moving object according to the present invention is applied.

FIG. 3 is an enlarged view showing one embodiment of a bumper device for a mobile object according to the present invention.

FIG. 4 is an enlarged view showing one embodiment of a bumper device for a moving body according to the present invention.

FIG. 5 is an enlarged view showing one embodiment of a bumper device for a moving body according to the present invention.

FIG. 6 is an enlarged view showing one embodiment of a bumper device for a mobile object according to the present invention.

FIG. 7 is a diagram illustrating a comparison between a bumper using a slide mechanism and a bumper using a link mechanism.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Lawn mower 2 Main frame 3 Engine 4 Front wheel 5 Rear wheel 6, 7 Lawn mowing unit 8 Hydraulic pump 9 Seat (for operator) 10 Steering handle 11 Operating lever 12 Bumper (12F is for the front, 12R is for the rear) 13 Joint link mechanism (13F is for front, 13R is for rear) 14 Obstacle sensor (14F is for front, 14R is for rear) 15 Left switch 16 Right switch 20 Control device 21 Wireless device O Obstacle

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Shintaro Hatsumoto 7-1-1, Higashi Narashino, Narashino-shi, Chiba Industrial Equipment Division, Hitachi, Ltd. (72) Inventor Kuniya Kaneko 1-26, Miyuki-cho, Toyokawa-shi, Aichi Prefecture Co., Ltd.Kyoei In-house Co., Ltd. Mutual prosperity

Claims (2)

[Claims] 1. A bumper device for a mobile body having a buffering function and an obstacle detecting function, wherein an articulated link mechanism for attaching a bumper to a vehicle body is provided, and the bumper is given to the bumper by the articulated link mechanism. And left and right sensor means for independently detecting the angular displacement of the left rear arm and the right rear arm of the articulated link mechanism are provided, and at least one of the left and right sensor means is provided. Wherein at least one of deceleration control and stop control of the moving body is executed when the angular displacement of the arm is detected. 2. The invention according to claim 1, wherein the bumper includes sensor means for detecting an obstacle, and when an obstacle is detected by the sensor means, at least one of deceleration control and stop control of the moving body is executed. A bumper device for a mobile object, characterized in that the bumper device is configured to be operated.