JPH0216251Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention provides a displacement detection mechanism for a steering device;
In particular, the present invention relates to a displacement detection mechanism for effectively detecting rotational displacement between a steering shaft and a shaft coupled to a steering wheel.

A steering device 1 as shown in FIG. 1 generally includes a steering wheel 2 disposed in a vehicle interior, a steering shaft 3 whose one end is connected to the steering wheel 2 and is rotatable integrally with the steering wheel 2, and a vehicle body panel. A steering column 4 is attached via a bracket 5 to rotatably supports a steering wheel 2 and a steering shaft 3, a first universal joint 6 is connected to the other end of the steering shaft 3, and a first universal joint 6 is provided outside the vehicle interior. a steering gear 8 connected to the steering gear 8, a second universal joint 7 coupled to the steering gear 8, and a universal joint 7 provided between the first and second universal joints 6 and 7, and which is provided to prevent vibrations from the road surface from the tires, the engine, and the suspension. and an intermediate member 9 that prevents vibrations from being transmitted to the steering wheel.

When such a steering device adopts a power steering system, this steering device 1 throttles hydraulic oil from an oil pump driven by an on-vehicle engine using a control valve that responds to the steering load. Power assist is obtained by supplying hydraulic pressure to one chamber of the power cylinder corresponding to the steering direction, thereby enabling light power steering. In such a device, if the oil pump is configured to be driven by the engine even during non-steering operation, the oil pump will be driven in vain during this time, resulting in poor engine fuel efficiency. ,
An energy-saving steering device has been proposed that detects this state and releases the supply of driving force between the engine and the oil pump. In such a steering device, for example, during a steering operation, the relative rotational displacement between the steering shaft 3 and the intermediate member 9 connected to the steering shaft 3 via the first universal joint 6 is considered as a relative rotational displacement. However, there is a device as shown in FIG. 2, for example, as a device for detecting heel displacement.

This includes a drive shaft directly connected to the steering wheel 2 by connecting the intermediate member 9 to the output side yoke of the first universal joint 6, that is, a torque transmission shaft 9a, and a material such as rubber attached to the torque transmission shaft 9a. A driven shaft 9b is connected to a driven shaft 9b for relative rotational displacement via an elastic member 10 made of lines 11, 12
and the steering column 4 using a contact energizing mechanism.
Power is being supplied to the side. That is, a contact piece 9c is attached to the torque transmission shaft 9a, while a contact piece 9d is attached to the driven shaft 9b at a predetermined angular interval with respect to the contact piece 9c, and one contact piece 9c is connected to the lead wire 11, for example. and the other contact piece 9d.
is connected to the lead wire 12. On the contrary,
A support plate 13 is fixedly attached to the steering shaft 3, and movable contacts 14 and 15 are arranged in a ring shape on the side surface of the support plate 13 at a predetermined interval in the radial direction with respect to the axis O of the steering shaft 3. It is installed in Further, the steering column 4 has a fixed contact piece 16 having a contact point 16a.
and a fixed contact piece 17 having a contact 17a are attached, the contact 16a being in elastic contact with the movable contact 14, and the contact 17a being in elastic contact with the movable contact 15. and,
Lead wires 18 and 19 are connected to the fixed contact pieces 16 and 17 for supplying power to various devices attached to the vehicle body. Therefore, when the steering shaft 3 rotates due to a steering operation, the torque transmission shaft 9a rotates integrally with the steering shaft 3, and a predetermined distance is created between the torque transmission shaft 9a and the driven shaft 9b by the action of the elastic member 10. When rotational displacement occurs,
The contact piece 9c and the contact piece 9d come into contact to perform a switch-on operation and detect the rotational displacement. In order to absorb the rotational displacement between the torque transmission shaft 9a and the driven shaft 9b and the rocking in the first universal joint 6 at this time, the lead wires 11 and 12 are given some slack. .
In addition, the reference numeral 20 in FIG. 2 indicates the steering column 4.
This is a bearing that rotatably supports the steering shaft 3, and reference numeral 21 is a boot that covers and protects the first universal joint 6.

However, in the case of the displacement detection device 1 of the steering device 1, the displacement detection and power supply structure is installed across the steering wheel 2 side and the steering gear 8 side with respect to the first universal joint 6. Therefore, the structure is complicated, and there is a possibility that the lead wires 12, 12 may be broken due to expansion and contraction. In addition, since power is supplied from the movable parts such as the steering shaft 3 to the non-movable parts such as the steering column 4 by the sliding contact between the two, the contacts 14 and 16a and the contact 1
5 and 17a, and there was a fear that the rotational displacement of the steering device 1 could not be detected accurately.

The present invention was developed by focusing on these conventional problems, and its purpose is to create a steering system that can operate reliably and accurately detect rotational displacement in the steering system while minimizing the number of power supply parts. An object of the present invention is to provide a displacement detection mechanism.

In order to achieve the above object, the present invention includes a driving shaft directly connected to a steering wheel constituting a steering device, and a driven shaft that receives torque from the driving shaft and transmits torque to the steering gear, that is, a driving shaft. The transmission shaft is rotatably connected to the transmission shaft via an elastic member, and a guide portion having a concave or convex cross section is provided on the outside of one of the shafts and extends in the axial direction, and the shaft is movable while being guided by this guide portion. In addition, a sliding member is provided that is prevented from rotating around the shaft, a fixing member is provided that is fixed to the other shaft and can rotate integrally, and a surface of the sliding member and the fixing member that oppose each other is provided. A displacement converting mechanism is installed in which recesses are formed in each of the recesses, rolling elements that loosely fit between the recesses are loaded, and the sliding member is biased toward the fixed member by an elastic body, and A switch mechanism is provided that operates on and off according to the displacement of the sliding member, and when a rotational displacement occurs between the two shafts, the displacement conversion mechanism converts this rotational displacement into an axial displacement of the sliding member. However, the gist is that this is detected by the operation of a switch mechanism. In addition, the connection between the sliding member and the guide portion extending to the power transmission shaft on one shaft is a spline connection or a key in order to enable movement of the slider as the sliding member in the axial direction. There are groove connections, etc. Since the switch mechanism is attached to the vehicle body side corresponding to the mover, all electrical components such as lead wires can be installed on the vehicle body side, and there is no need to provide fixed and movable contacts for power supply. There is no problem of causing defects.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 3 is a diagram showing an embodiment of the present invention. The displacement detection mechanism of the steering device according to this embodiment connects the driving shaft connected to the steering wheel 2, that is, the steering shaft 3, and the driven shaft, that is, the power transmission shaft 25 for inputting the first universal joint, to the vibration isolating rubber. 27 in a rotatably displaceably connected joint part. The anti-vibration rubber 27 is fixed to the end of the power transmission shaft 25 on the steering shaft 3 side by baking, and a tube-shaped collar 2 is attached to the outer periphery of the vibration-proof rubber 27.
8 is baked and fixed, and is tightly fitted to the inner periphery of the tubular steering shaft 3 via this collar 28. A spline shaft 26 is fixed to the end of the power transmission shaft 25 on the universal joint 6 side, and a slider 30 having a spline formed on its inner diameter is fitted into the spline shaft 26 so as to be slidable in the axial direction. It is worn. The mover 30 is made of a disk member having a predetermined thickness, and one side of the mover 30 is arranged to face a sleeve 40 provided at the tip of the steering shaft 3. Furthermore, cam grooves 32 and 33 are formed on the opposing side surfaces of the slider 30 and the sleeve 40, respectively, and rolling elements, that is, balls 34 are loosely fitted into these cam grooves 32 and 33. It is rotatably loaded to form a cam mechanism. Furthermore, the cam groove 32,
33 and the ball 34, a spring 35 is interposed between the mover 30 and the first universal joint 6, and constantly urges the mover 30 toward the side of the steering shaft 3. ing. On the other hand, a micro switch 36 is fixed to the steering column 4 which rotatably supports the steering shaft 3 via a bearing 29 with a screw 41 with its contact 37 corresponding to the slider 30. Extending lead wires 38 and 39 are connected to various devices.
The movable element 30, the sleeve 40, the ball 34, and the spring 35 constitute a displacement conversion mechanism that converts the rotational displacement between the steering shaft 3 and the power transmission shaft 25 into an axial displacement of the movable element 30. There is. Moreover, a displacement detection device is realized by this displacement conversion mechanism and the microswitch 36.

With this configuration, when the steering wheel 2 is operated to rotate in one direction, if the steering force on the steering shaft 3 is larger than a certain constant value, the vibration isolating rubber 27 is sheared and deformed, causing the steering shaft to rotate. 3 and the power transmission shaft 25 , and the sleeve 40 is rotationally displaced with respect to the mover 30 .
Therefore, the cam groove 33 moves the ball 34 in the direction of rotation of the steering shaft 3 relative to the cam groove 32.
The ball 34 rides up from the cam groove 32 of the mover 30 to the side surface. As the ball 34 rides up, the slider 30 receives an axial pressing force toward the first universal joint 6 indicated by the arrow S in FIG. 3, and resists the heating force of the spring 35. It makes a sliding movement. Then, the contactor 37 of the microswitch 36 protrudes as the movable element 30 slides, turns the microswitch 36 on (or off), and detects the displacement of the steering device 1. When the micro switch 36 is turned on, current is conducted (or cut off) through the lead wires 38 and 39, and the equipment connected thereto is activated (or stopped). For example, in the case of a power steering device, when the displacement of the steering device is detected, the micro switch 36
is turned on, operating the electromagnetic clutch that drives the oil pump.

Therefore, the displacement caused by the steering operation in the steering device 1 is always detected by the on/off operation of a switch provided on a part fixed to the vehicle body, such as the steering column 4, so that the steering device cannot be moved. There is no need to supply power from the part to the stationary part using lead wires and contact terminal members.

In this embodiment, the driving side shaft is the steering shaft 3, the driven side shaft is the power transmission shaft 25 connected to the first universal joint 6, and both shafts 3, 25 are used.
Although the displacement detection mechanism is arranged at the connection part of the first universal joint 6 and the second
The displacement may be detected by installing the micro switch 36 between the universal joint 7 and the vehicle body panel near the displacement converting member.

As described above, according to the displacement detection mechanism according to the present invention, the driving shaft and the driven shaft in the steering device are elastically connected to enable rotational displacement, and the rotational displacement is transferred between the two shafts by the sliding member. A displacement conversion mechanism that converts the rotational displacement into axial displacement and a switch mechanism that operates on and off according to the displacement of the sliding member are provided, so the power supply structure for detecting the rotational displacement can be simplified. Summer. In addition, this displacement detection mechanism eliminates the need to provide a lead wire from the movable part of the steering device to the movable part, and also eliminates the need to supply current through the contact action of the contact terminal member. It is possible to prevent instability of the operation of the device due to wire breakage, poor contact of the contact terminal member, etc., and the displacement detection accuracy of the steering device can be further improved. Furthermore, even if the dimensions of the rubber provided between the drive-side shaft and the driven-side shaft differ depending on the vehicle model, you can simply change the shape of the recesses of the sliding member or fixed member, the size of the rolling elements, etc. It also has the effect of increasing the degree of freedom in design without reducing cost and effort.

[Brief explanation of the drawing]

FIG. 1 is an overall perspective view showing a general example of a steering device to which the present invention is applied, FIG. 2 is an enlarged explanatory view showing a displacement detection mechanism of a conventional steering device,
FIG. 3 is an enlarged explanatory diagram showing a displacement detection mechanism of a steering device according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Steering device, 2... Steering wheel, 3... Steering shaft (drive side shaft), 4... Steering column, 6... First universal joint, 7... Second universal joint, 8... Steering gear, 25... Power transmission shaft (driven shaft), 30... mover,
32, 33...Cam groove, 34...Ball, 35...Spring, 36...Micro switch (switch mechanism), 40...Sleeve.

Claims (1)

[Claims for Utility Model Registration] A drive-side shaft rotatably attached to a vehicle body panel and directly connected to a steering wheel, and a drive-side shaft rotatably connected to the drive-side shaft via an elastic member. In addition, in a steering device having a driven shaft connected to a steering wheel of a vehicle, a guide portion having a concave or convex cross section is provided on the outside of one of the shafts between the driving shaft and the driven shaft. A sliding member is provided which extends in the axial direction, is guided by the guide portion, is movable, and is prevented from rotating around the axis, and a fixed member is fixed to the other shaft and is rotatable as a unit. recesses are formed in mutually opposing surfaces of the sliding member and the fixing member, and a rolling element that loosely fits between these recesses is loaded so that the sliding member is fixed to the fixing member by an elastic body. A displacement exchange mechanism that is biased in the direction of is installed, and a switch mechanism that operates on and off according to the displacement of the sliding member is installed, and when rotational displacement occurs between the two shafts, the displacement exchange mechanism is installed. A displacement detection mechanism for a steering device, characterized in that the rotational displacement is converted into an axial displacement of the sliding member, and this is detected by the operation of a switch mechanism.