JPH0143667B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a steering device for a dual-handle vehicle.

[Conventional technology] Vehicles with handles on both left and right driver seats are
For example, it is used for vehicles that require driving by pulling to the left side of the road, such as training vehicles and road cleaning vehicles.

For example, a double-handle vehicle such as a road cleaning vehicle disclosed in Japanese Patent Application Laid-Open No. 55-19678 does not have a clutch mechanism on one of the steering shafts, so when one handle is operated, the other handle is always activated. It follows and operates. For this reason, when the vehicle is used as a dual-handle vehicle for training purposes, when the student is operating the steering wheel, the steering wheel in the instructor's seat also rotates at the same time, so the instructor cannot rest with his/her hands on the steering wheel.

Therefore, it is desirable that one of the handles does not normally rotate, but is operated as needed, and that the operation of one of the handles is given priority over the other.

Furthermore, in the dual-handle vehicle, switching control of pressure fluid from the hydraulic pump is performed only by manually operating the lever on the directional control valve, so switching control cannot be performed quickly, and only one of the directional control valves, which should be given priority, Emergency steering operations using the steering wheel may not be possible.

In addition, the steering device of the training vehicle disclosed in Publication of Utility Model Publication No. 1973-19532 also has the ability to connect the steering wheel post on the trainee's side and the steering transmission section even when the clutch device on the instructor's side is connected. Since the connection will not be broken, if the operating force on the trainee's side is strong, there is a risk that the instructor's steering operation will become impossible. Because they are now being made to be done manually, they lack speed,
There was a risk that emergency steering operations using the driver's side steering wheel would become impossible.

[Problems to be Solved by the Invention] In view of the above points, an object of the present invention is to selectively connect both power steering devices to a pressure fluid source via a switching valve, so that one handle can be connected as needed. The actuator that operates the clutch mechanism provided on one of the steering shafts and the switching valve of both power steering devices are operated using electromagnetic means and pressure fluid. An object of the present invention is to provide a steering device for a dual-handle vehicle, which improves the speed and reliability of steering operations in an emergency using a steering shaft-side handle having the clutch mechanism.

[Means for Solving the Problem] In order to achieve the above object, the configuration of the present invention is connected to the left and right driver's seat handles via steering shafts, and is selectively connected to a pressure fluid source via a switching valve. and a clutch mechanism operated by an actuator is provided on one steering shaft, such that when the clutch mechanism is connected, the power steering device of the one steering shaft is connected to the pressure fluid source. Further, there is provided a steering device for a dual-handle vehicle in which the switching valve and the actuator are connected to a pressure fluid source via an electromagnetic switching valve operated by a control lever.

[Operation] When the operating lever is operated to operate the electromagnetic switching valve, the supply of pressure fluid from the pressure fluid source is switched from the actuator to the switching valve. Pressure fluid is now selectively supplied to the power steering device on the side, and steering operations are performed only by the handle on the side of the clutch mechanism.

[Embodiments of the Invention] The steering system for a dual-handle vehicle of the present invention will be described based on an embodiment. As shown in FIG. Devices 13, 3 are provided, and their outputs,
That is, the steering arms are connected to each other by a tie rod (not shown).

Steering shafts 2 and 12, which are input shafts of power steering devices 3 and 13, are operated by handles 1 and 11, respectively. In the power steering device 3 in the instructor's seat, a servo control valve is operated by the rotation of the steering shaft 2, and a hydraulic pump 2 as a pressure fluid source is installed in one end chamber of the power cylinder.
2 is supplied via a conduit 4 for pressurized liquid, and the pressurized liquid in the other end chamber is returned to the liquid tank 21 via a conduit 5. Similarly, in the power steering device 13 of the student seat, the servo control valve is actuated by the rotation of the steering shaft 12, and pressure liquid is supplied to the one end chamber of the power cylinder from the hydraulic pump 22 through the conduit 14.
The pressure liquid from the other end chamber is returned to the liquid tank 21 via the conduit 15.

The hydraulic pump 22 is connected to the conduits 14 and 4 via a switching valve 23 so that it can communicate with the conduits 14 and 4 alternatively so that the operation of the handle 1 on the instructor's seat can give priority to steering the vehicle in an emergency. This switching valve 23 is operated by fluid pressure, and the electromagnetic switching valve 2
4 is a switch 2 which is opened and closed by an operating lever 28.
7, pressurized fluid is applied from the pressure fluid tank 25 as a source of pressure fluid via the conduit 29, the solenoid switching valve 24 and the conduit 20 to the switching valve 23, switching the switching valve 23, thereby causing the A pressure pump 22 is connected in communication with conduit 4 . At the same time, the conduit 30 is isolated from the pressure fluid tank 25 and opened to the atmosphere, causing the spring to return the hydraulic actuator 26 and connecting the clutch mechanism 31, which will be described below.

Further, a clutch mechanism 31 for disconnecting and disconnecting the rotational connection between the steering shaft 2 of the steering device in the instructor's seat and the handle 1 is provided.
The structure is as follows.

As shown in FIG. 2, the end of the lower shaft 2a of the steering shaft 2 is supported by a bearing 38 on the end wall 37 of a housing 39 fixed to the vehicle body, and the lower shaft 2a of the steering shaft 2 is provided with teeth 42a on the upper end surface. Clutch plates 42 are connected with serrations 42b. On the other hand, the end of the upper shaft 2b of the steering shaft 2 that supports the handle 1 is supported by the end wall 32 of the housing 39 with a bearing 33.
A clutch plate 40 is provided with teeth 40a that mesh with teeth 42a of the clutch plate 42 on a spline 2c formed at the end of the upper shaft 2b.
bonded with 0d. A clutch spring 34 is interposed between the annular recess 40b of the clutch plate 40 and the end wall 32. An annular groove 40c is formed on the peripheral surface of the clutch plate 40, and a shift fork 41 that engages with the annular groove 40c is supported by the rod 35. This rod 35 is slidably supported substantially parallel to the steering shaft 2 and is connected to a rod 36 of a hydraulic actuator 26 supported in a housing 39.

Further, S in FIG. 2 indicates the stroke when the rod 35 slides.

The fluid pressure actuator 26 is, as is known,
A piston is fitted inside the cylinder to form a working chamber at one end and an atmospheric chamber at the other end, from which a rod 36 connected to the piston projects.

In the above configuration, when the switch 27 is opened by the operation lever 28 during normal driving practice, the electromagnetic switching valve 24 connects the conduit 29 to the conduit 30 and isolates it from the conduit 20.
Therefore, the pressure fluid from the pressure fluid tank 25 is supplied to the fluid pressure actuator 26, so that the rod 36 is projected upward, and the clutch plate 40 is pushed up by the shift fork 41 against the force of the spring 34. The engagement with the clutch plate 42 is released.

Further, the switching valve 23 supplies the pressure liquid of the hydraulic pump 22 to the power steering device 13 via the conduit 14.
In this state, steering power is generated by the power steering device 13 operated by the handle 11 of the student seat, and the student can easily perform the steering operation. Since the instructor's steering wheel 1 is isolated from the steering shaft 2, even if the instructor holds the steering wheel 1, the steering wheel 1 will not be rotated by the steering operation at the student's seat, thereby avoiding trouble. can.

However, if the student's steering operation is immature and an accident such as a collision or a crash is predicted, the instructor immediately closes the switch 27 using the operating lever 28, the electromagnetic switching valve 24 is switched, and the conduit 29 is switched to the conduit 30. The connection is cut off and connected to the conduit 20. Accordingly, the hydraulic actuator 26 is returned and the force of the spring 34 engages the teeth 40a of the clutch plate 40 with the teeth 42a of the clutch plate 42. At the same time, the switching valve 23 is actuated and pressure fluid from the hydraulic pump 22 is supplied to the conduit 4 and is no longer supplied to the conduit 14. Therefore, the power steering device 13 on the student side becomes inactive, and when the instructor operates the steering wheel 1, the power steering device 3 operates in accordance with the instructor's operation, thereby preventing accidents. Can be done.

FIG. 3 shows a second embodiment of the clutch mechanism, and this clutch mechanism 31A has spline shafts 46 and 45 provided at the ends of the lower shaft 2a and the upper shaft 2b of the steering shaft 2, respectively, and meshes with the spline shafts 46 and 45. Clutch sleeve 47 with spline hole 48
is operated by a fluid pressure actuator with a shift fork 41 that engages with this outer circumferential annular groove 40c. Since the structure of the clutch mechanism 31 is simpler in this case, it can be provided at a lower cost.

[Effects of the Invention] As described above, the steering device for a dual-handle vehicle of the present invention is connected to the left and right driver's seat handles via steering shafts, respectively, and is selectively connected to a pressure fluid source via a switching valve. a power steering device connected thereto, a clutch mechanism operated by an actuator is provided on one steering shaft, and when the clutch mechanism is connected, the power steering device of the one steering shaft is connected to the pressure fluid source. Since the switching valve and the actuator are connected to a pressure fluid source via an electromagnetic switching valve operated by an operating lever, the dual power steering device is configured to selectively connect the pressure fluid source to the switching valve and the actuator. Because they are connected, one handle can be prevented from being rotated if necessary, and the other handle can be operated preferentially, and the clutch mechanism and both power steering devices provided on one of the steering shafts can be operated. Since the switching valve is controlled by electromagnetic means and pressure fluid,
The present invention has the effect of providing a steering device for a dual-handle vehicle that improves the speed and reliability of steering operations in an emergency using the steering shaft-side handle having the clutch mechanism.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram of a steering device for a dual-handle vehicle according to the present invention, Fig. 2 is a side sectional view of a clutch mechanism in the same device, and Fig. 3 shows a second embodiment of the clutch mechanism. FIG. 1, 11: Handle, 2, 12: Steering shaft, 3,
13: Hydraulic power steering device, 21: Liquid tank, 22:
Hydraulic pump, 23: switching valve, 24: electromagnetic switching valve,
25: Pressure fluid tank, 26: Fluid pressure actuator, 27: Switch, 28: Operation lever, 3
1, 31A: Clutch mechanism, 40, 42: Clutch plate, 41: Shift fork, 45, 46: Spline shaft, 47: Clutch sleeve, 48: Spline hole.

Claims (1)

[Claims] 1 Equipped with a power steering device connected to the left and right driver's seat handles via steering shafts and selectively connected to a pressure fluid source via a switching valve, and a clutch operated by an actuator on one steering shaft. a mechanism is provided, and the switching valve and the actuator are connected via an electromagnetic switching valve operated by a control lever so that the power steering device of the one steering shaft is connected to the pressure fluid source when the clutch mechanism is connected. A steering device for a dual-handle vehicle connected to a source of pressure fluid.