JPH0712190A - Automatic traveling vehicle - Google Patents

Abstract

PURPOSE:To provide an automatic traveling vehicle capable of restraining the vehicle speed from becoming suddenly high at the time of travel load becoming suddenly light as in the case of traveling on a down slope so as to maintain the vehicle speed constant. CONSTITUTION:A belt type continuously variable transmission 8 is interposed in the transmission system of an engine 7 and driving wheels, and the speed change split pulley 8b of the belt type continuously variable transmission 8 is formed in such a way that the belt winding width is expandable. An automatic traveling vehicle of such constitution is provided with a detecting means B for detecting whether or not the driving load of the output shaft of the belt type continuously variable transmission 8 has a tendency to become light, and a regulating means A for regulating the belt winding width of the split pulley 8b into the narrow state on the basis of the detection result of the driving load having a tendency to become light by the detecting means B.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic traveling vehicle such as a golf cart, which has a belt type continuously variable transmission interposed in a transmission system between an engine and driving wheels, and the belt type continuously variable transmission. The invention relates to an automatic traveling vehicle in which the shifting pulley is configured such that the belt winding width can be freely expanded and contracted.

[0002]

2. Description of the Related Art Conventionally, in this type of automatic traveling vehicle, it is known that the vehicle automatically travels on a predetermined traveling path by guided steering or wireless steering. By operating the split pulley of the belt type continuously variable transmission according to the load, the vehicle speed can be kept constant regardless of the fluctuation of the running load.

[0003]

However, in the above-mentioned conventional structure, when there are many ups and downs in a running place such as a golf course, the running load becomes large on the uphill and the low speed naturally occurs. It can be operated and driven with high torque, but since the traveling load on the downhill decreases suddenly, the speed increase rate tends to be rapid, and the belt type continuously variable transmission reduces the vehicle speed to the predetermined vehicle speed. It took time to go, and there was a problem that the vehicle body could not be smoothly steered. The present invention has been made in view of the above circumstances, and suppresses a sudden increase in vehicle speed when the traveling load is rapidly reduced, such as when traveling on a downhill. It is an object of the present invention to provide an autonomous vehicle capable of maintaining a vehicle speed.

[0004]

In order to achieve the above object, the automatic traveling vehicle according to the first aspect of the present invention has the structure described above and has a light drive load on the output shaft of the belt type continuously variable transmission. The detection means for detecting whether or not there is a tendency to be provided is provided, and based on the detection result that the drive load by the detection means tends to be light, the split pulley is restricted to a narrow belt winding width. A characteristic configuration is that a regulation means is provided. In order to achieve the above-mentioned object, the automatic traveling vehicle according to the second aspect of the present invention has the structure described above, and detects whether or not the drive load of the output shaft of the belt type continuously variable transmission tends to be light. The detecting means is provided, and the load increasing means for increasing the load on the output of the belt type continuously variable transmission is provided based on the detection result that the driving load by the detecting means tends to be light. The configuration. The operation and effect of this characteristic configuration are as follows.

[0005]

In other words, according to the first aspect of the present invention, the detection means for detecting whether or not the drive load of the output shaft of the belt type continuously variable transmission tends to become lighter detects that the drive load tends to become lighter. Then, the belt pulley is regulated to a low speed state by regulating the belt winding width of the split pulley to a narrow state by the regulation means, so that it is possible to prevent the vehicle speed from suddenly increasing, and the predetermined speed can be avoided. The vehicle speed can be maintained.
Further, according to the second aspect of the present invention, when the detection means for detecting whether or not the drive load of the output shaft of the belt type continuously variable transmission tends to be lightened, it is detected that the drive load tends to be lightened. By increasing the load on the output of the continuously variable transmission by the load increasing means, the output of the belt continuously variable transmission is maintained at a low speed by the load, so that it is possible to suppress a sudden increase in vehicle speed. It is possible to maintain a predetermined vehicle speed.

[0006]

Therefore, according to the present invention, when the load of the output shaft of the belt type continuously variable transmission means is lightened, for example, when the vehicle travels on a downhill, the belt type continuously variable transmission is set to a low speed state. By forcibly restricting or increasing the load on the output of the belt type continuously variable transmission, the output of the belt type continuously variable transmission is forcibly maintained at a low speed state, and the vehicle speed is unreasonably high. Therefore, the steering can be performed satisfactorily.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 shows a golf cart as an example of the automatic vehicle according to the present invention. The golf cart according to the first and second embodiments of the present invention will be described. In this golf cart, a pair of left and right front wheels 1, 1 and a pair of left and right rear wheels 2, 2 as driving wheels movably support a vehicle body frame 3 to form a traveling vehicle body V. In addition, the boarding operation unit 4, the driving unit 5, the luggage stand 6 and the like are mounted and configured.

As shown in FIG. 1, the prime mover 5 is provided with an engine 7, a belt type continuously variable transmission 8 and a mission case 9, and the rear wheel 2 is driven by the output from the mission case 9. , 2 are driven. The belt type continuously variable transmission 8 includes an output shaft 7 of the engine 7.
A transmission belt 8c is stretched over a drive pulley 8a that is interlocked with a and a driven pulley 8b that is interlocked with the input shaft 9a of the mission case 9 and has a split pulley structure. Tension is applied by the biased tension pulley 8d. The driven pulley 8b is slidable with respect to the fixed split pulley 11 which is freely rotatable around the end of the input shaft 9a and whose position is regulated in the axial direction, and the shaft 9a in the axial direction of the input shaft 9a. The movable split pulley 12 is provided so as to freely rotate. The movable split pulley 12 has a cam portion 13 in which the transmission case 9 has an inclined cam surface 13a on its lower surface portion.
And a cylindrical cam 15 having a cam portion 14 having an inclined cam surface 14a that is guided by contacting the inclined cam surface 13a of the cam portion 13 by spline fitting to the input shaft 9a. It is provided slidably in the axial direction. Then, the tubular cam 15 is pressed by the electric cylinder 16 so that the movable split pulley 12 contacts and regulates the movable split pulley 12 so that the movable split pulley 12 can be pressed and moved. With this structure, the cylindrical cam 15 is pressed by the electric cylinder 16 so that the cylindrical cam 15 is moved to the electric cylinder 1.
6, the inclined cam surface 14a of the cam portion 14 of the tubular cam and the inclined cam surface 13a of the cam portion 13 of the movable split pulley 12 are in contact with each other in this state. Rotational power from the movable split pulley 12 is transmitted to the input shaft 9a via the surfaces 13a and 14a. Further, the inclined cam surface 13a of the movable split pulley 12 which is urged to be separated from the fixed split pulley 11 by the tension of the transmission belt 8c, and the inclined cam of the tubular cam 15 whose position is regulated by the pressing force of the electric cylinder 16. The movable split pulley 12 is located at a position where the acting forces in opposite directions on the surfaces abutting on the surface 14a are balanced, and the winding diameter of the transmission belt 8c and the winding diameter of the drive pulley 8a at that position. The vehicle speed with respect to the engine rotation speed at that time is set by the relationship with. Therefore, the cylindrical cylinder 1 is driven by the electric cylinder 16.
As the movable split pulley 12 is moved closer to the solid split pulley 11 via 5, the vehicle speed is continuously changed so that the vehicle speed becomes lower. The position of the inclined cam surface 13a of the movable split pulley 12 relative to the inclined cam surface 14a of the tubular cam 15 also changes due to changes in the traveling load, and for example, when the load decreases, the speed change transmission speed increases so that the movable split pulley speed increases. 12 moves toward the tubular cam 15, and the movable split pulley 12 moves away from the tubular cam 15 so that the shift transmission speed decreases when the load increases.
It is designed to automatically maintain a predetermined vehicle speed. or,
The electric cylinder 16 constitutes a regulating means A that presses the fixed split pulley 11 to the brow so as to regulate the movable split pulley 12 to a predetermined low speed transmission state based on a command from the control device 10. Further, the transmission case 9 of the movable split pulley 12 is provided with a fixed friction member 17 in an annular shape around the rotation axis of the transmission case 9 and the electric cylinder 16 extends a predetermined amount or more. A movable friction member 18 that regulates the position of the movable split pulley 12 by pressingly contacting the fixed friction member 17 is slidably fitted around the outer periphery of the cylindrical cam 15.

A preview sensor 19 composed of a photoelectric sensor is arranged at the front end of the traveling vehicle V. As shown in FIG. 3, the preview sensor 19 transmits an optical signal toward the front lower side, receives the optical signal reflected on the ground or the like, and receives the received signal from the control device 1.
By inputting 0, the distance L between the ground and the preview sensor 19 can be calculated. here,
The preview sensor 19 and the control device 10 are detecting means B.
It is what constitutes. Then, with respect to the detection distance L obtained in a horizontal traveling place, the detection distance Lu when the vehicle body is on a level ground and there is an uphill ahead is detected as a value smaller than the distance L, while the vehicle body is leveled on a level ground. Since the detection distance Ld when there is a downhill ahead in a certain state is detected as a value larger than the distance L, the control device 10 determines that there is a downhill ahead based on the detection result of the preview sensor 19. When judged, the control device 10 outputs a signal for extending the electric cylinder 16 to have a predetermined length, whereby the electric cylinder 16 is extended to the predetermined length, and the electric cylinder 16 is driven at the predetermined length. The movable split pulley 12 is moved to the cam portion 13 so that the winding diameter of the transmission belt 8c with respect to the pulley 8b becomes such a large diameter that a predetermined low speed running state appears. 4 is brought close to the fixed split pulley 11 through. In this case, the extension length of the electric cylinder 16 may be set so that the movable friction member 18 also contacts the fixed friction member 17.
The extension length of the electric cylinder 16 may be set so that the movable friction member 18 does not contact the fixed friction member 17. When the extension length of the electric cylinder 16 is set so that the movable friction member 18 does not contact the fixed friction member 17, the electric cylinder 16 is further extended based on a predetermined extension signal. Then, at that time, the movable friction member 18 may be brought into contact with the fixed friction member 17, and further, the movable friction member 18 may not be brought into contact with the fixed friction member 17 while going downhill. Movable split pulley 12 for sudden reduction of traveling load after traveling
Alternatively, the movable friction member 18 may abut against the fixed friction member 17 when the fixed split pulley 11 moves to the armpit.

Next, an embodiment of the second invention will be described. As shown in FIG. 4, the driven pulley 8b of the belt type continuously variable transmission 8 in the golf cart as an example of the automatic traveling vehicle according to the second aspect of the invention is, for example, automatically driven by the traveling load as in the first aspect of the invention. When the load becomes lighter, the movable split pulley 12 moves closer to the fixed split pulley 11 due to the abutment guide between the cam portion 13 and the cam portion 14, and the low speed drive shifts. When the load becomes heavy, the cam portion 13 and the cam portion 13 move. When the movable split pulley 12 is separated from the fixed split pulley 11 by contact guide with 14, the high speed drive shifts to a high speed, and the fixed split pulley 11 has an annular fixed friction on the outer surface thereof. The member 20 is provided, and the fixed friction member 20
A movable friction member 21 disposed so as to face each other is provided so as to be movable in the perspective direction with respect to the fixed friction member 20 by driving an electric actuator 22 such as an electric motor. The electric actuator 22 is drive-controlled by the control device 10. Then, the inclination sensor 2 is attached to the traveling vehicle body V.
3 is mounted, and the inclination sensor 23 detects inclination with respect to the traveling direction of the vehicle body and inputs the detection information to the control device 10. Here, the tilt sensor 23 and the control device 10 constitute a detecting means B.

With this configuration, in the control device 10, when the tilt sensor 23 detects that the traveling vehicle body V is in the forward descending state by a predetermined angle or more, the electric actuator 22 is driven to drive the vehicle on a normal level ground. In the state in which the movable friction member 21 is in contact with the movable friction member 21, the fixed friction member 20 and the movable friction member 21 are pressed against each other.
Move to the crab. Due to the contact pressure between the fixed friction member 20 and the movable friction member 21, a load is applied to the input shaft 9a of the transmission case 9, so that the rotation speed of the driven pulley 8b decreases. Here, the fixed friction member 2
0, the movable friction member 21 and the electric actuator 22 are
It constitutes load increasing means C.

The present invention may be carried out as follows in addition to the above embodiment. (A) As the detecting means, a torque sensor or the like capable of detecting a change in drive torque of the transmission system in the traveling device is used.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing a driving unit.

FIG. 2 is a vertical sectional side view showing a driven pulley of a belt type continuously variable transmission.

FIG. 3 is a side view showing a golf cart.

FIG. 4 is a vertical sectional side view showing a driven pulley of a belt type continuously variable transmission according to another embodiment.

[Explanation of symbols]

 2 drive wheels 7 engine 8 belt type continuously variable transmission 8b split pulley A regulating means B detecting means C load increasing means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshifumi Yamanaka 64 Ishizukita-cho, Sakai City, Osaka Prefecture Kubota Sakai Factory Co., Ltd. (72) Inventor Shigeru Tanaka 64, Ishizukita-machi, Sakai City, Osaka Kubota Sakai Co., Ltd. Inside the factory (72) Shinichi Kawabata 64 Ishizukita-cho, Sakai City, Osaka Prefecture Kubota Sakai Co., Ltd. (72) Inventor Yasushi Fujii 64, Ishizukita-machi, Sakai City, Osaka (72) Invention Yasuo Irie 64, Ishizukita-machi, Sakai City, Osaka Prefecture Kubota Sakai Factory Co., Ltd.

Claims (2)

[Claims] 1. A belt type continuously variable transmission (8) is provided in a transmission system between an engine (7) and a drive wheel (2), and the belt type continuously variable transmission (8) is used for shifting. Detection for detecting whether or not the drive load of the output shaft of the belt type continuously variable transmission (8) tends to be reduced in an automatic vehicle in which the belt winding width of the split pulley (8b) is freely expandable and contractible. With the provision of the means (B), the dividing pulley (8b) is regulated to have a narrow belt winding width based on the detection result that the driving load tends to be lightened by the detecting means (B). An automatic vehicle provided with means (A). 2. A belt type continuously variable transmission (8) is provided in a transmission system between an engine (7) and drive wheels (2), and the belt type continuously variable transmission (8) is used for shifting. Detection for detecting whether or not the drive load of the output shaft of the belt type continuously variable transmission (8) tends to be reduced in an automatic vehicle in which the belt winding width of the split pulley (8b) is freely expandable and contractible. With the provision of the means (B), the load increase for increasing the load on the output of the belt type continuously variable transmission (8) based on the detection result that the drive load tends to be lightened by the detection means (B) An automatic vehicle provided with means (C).