JPS6352002A - Steering angle detector - Google Patents

Abstract

PURPOSE:To accurate detect actual wheel steering angle information by providing a metallic core to a rod member which moves in the breadthwise direction of a car body by steering and then providing primary and secondary coils to the outer periphery at an interval. CONSTITUTION:A large-diameter part 12 is formed at some part on a rack shaft 4 which projects from a gear box 3 and metallic rings 13 and 13 made of copper, etc., are fitted to both ends to constitute a core 14. The primary coil 15 and secondary coils 16 and 16 on both sides are fixed successively on the outer periphery of the diameter part 12 on a car body side. Thus, a steering angle detector 11 is constituted. An AC voltage is applied to the coil 15, which is driven; when a core 14 moves right and left, a secondary voltage corresponding to its movement quantity is developed between the coils 16 and 16. Consequently, the moving direction and quantity of the shaft 14 are detected directly and the steering direction and angle of the front wheels 6 are therefore detected. A control signal 22 based on the steering information on the front wheels 6 and car speed information is inputted to a motor 23 and the rotation of the driving shaft 24 of the motor 23 is transmitted through a rear wheel steering gear box 25, a rack shaft 26, and a knuckle 27 to drive the rear wheels 28.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a steering angle detector using a differential transformer.

(Prior Art) For example, front and rear wheel steering (hereinafter abbreviated as 4WS) vehicles are equipped with a steering angle detector to detect steering angle information. Conventionally, detectors such as potentiometers and encoders have been installed. It was mechanically connected to the Pi rudder shaft and information about the rudder angle was obtained from the steering wheel angle.

(Problem to be solved by the invention) However, the steering force transmission path from the steering wheel to the wheels has mechanical backlash, twisting, etc., and the steering wheel has some play, so the steering wheel angle does not necessarily indicate the actual wheel steering angle. It is difficult to say that the information is accurate.

Furthermore, if a detector is mechanically connected to the steering function parts, vibrations of the steering gear parts can be prevented from rattling or twisting due to shock.
Also, it is easily affected by environmental changes such as dust and temperature.

Therefore, an object of the present invention is to accurately detect actual wheel steering angle information by arranging a detector on a rod member that moves in the width direction of the vehicle body by steering and serves as a steering angle output member to the wheels. In addition, by keeping the rod member and the detector in a non-contact state, the steering angle detector is not affected by rattling, twisting, or environmental changes, and can obtain accurate steering angle information. is to provide.

(Means for Solving the Problems) In order to achieve the above object, the present invention disposes a differential transformer on a rod member that moves in the width direction of the vehicle body by steering, that is, a metal core is provided on the rod member. , a primary coil and a secondary coil are provided at a distance from each other around the outer periphery of the core.

(Function) Since the amount of movement of the rod member forming the steering angle output member to the wheels is directly detected, the actual wheel steering angle information can be detected accurately.

Since this detection is performed using a differential transformer, the steering direction and steering angle can be detected simultaneously. Moreover, the core, primary and secondary
There is a required gap between the next coils, that is, there is no contact with the rod member, so the detection accuracy is not affected by rattling, twisting, dirt, etc. of the rod member, and the differential transformer Since it is resistant to environmental changes such as temperature, the reliability of steering angle detection is high.

Furthermore, if the voltage of the coil is monitored, disconnections and poor connections in the coil or conductor can be easily detected.

(Example) Examples will be described below based on the accompanying drawings.

Figure 1 shows a schematic plan view of the 4WS 9 position, where (1) is the handle, (2) is the steering shaft, (3) is the front wheel steering gear box, (4) is the rank shaft, and (5) is the knuckle arm. ,(
6) is the front wheel, and the rotation of the handle (1) is converted by the rank pinion mechanism in the gear box (3) into the width direction of the vehicle body (horizontal movement) of the rank shaft (4),
The front wheels (6) are steered via.

First, in the first embodiment, a steering angle detector (11) is placed on a rack shaft (4) protruding from a gear box (3). That is, as shown in FIG. 2, a large diameter part (12) is formed in a part of the rack shaft (4), and metal rings (13) made of copper or aluminum are attached to both ends of this large diameter part (12). , (la)
The metal core (1
4). On the other hand, on the vehicle body side, a primary coil (15) is fixed at a distance from the outer periphery of the large diameter part (12), and secondary coils (Is) are arranged and fixed on both sides of the primary coil (15). do. In this way, the core (14) provided on the roller shaft (4), the primary coil (15) provided on the vehicle body side, and the
Next coil (1G), (ts) and steering angle detector (11)
Configure.

This steering angle detector (11) is the same as a differential transformer, and is excited by applying AC voltage to the primary coil (15), and the core (14)
When the core (14) moves left and right, the secondary coil (16), (
16).This allows the direction and amount of movement of the rack shaft (4) to be directly detected, and therefore the 1tt wheel (B)
Information on the steering direction and steering angle can be obtained.

The front wheel steering information thus detected by the steering angle detector (11) is input to the control unit (22) together with, for example, the vehicle speed information detected by the vehicle speed detector (21), and control is performed based on the front wheel steering information and the vehicle speed information. A signal is input from the control unit (22) to the motor (23). The rotation of the drive shaft (24) of this motor (23) is controlled by the rear wheel steering gear box (25).
The rack and pinion mechanism inside converts the movement of the rank shaft (26) in the left and right direction, and the rear wheel (28) moves through the knuckle (27).
) is steered.

Next, FIG. 3 shows a second embodiment, and in this embodiment, a steering angle detector (1
1) and a rack shaft for rear wheel steering (2G
)h is also provided with a similar steering angle detector (111), and the rear wheel steering information detected by this rear wheel side steering angle detector (ill) is fed back to the control unit (22).

In addition, in FIG. 4 showing the third embodiment, the rack shaft on the rear wheel side (
A rod (28) parallel to the rod (28) was provided integrally, and a steering angle detector (111) was placed on this rod (29), and other parts were the same as in the second embodiment.

In the second embodiment, the steering angle detector is placed on the rack shaft that protrudes from the gear box, but it may also be placed on the rack shaft inside the gear box, as shown in FIG. 5 showing the fourth embodiment. In addition, a large diameter portion (12
) and a metal ring (13).
), and the primary coil (15) and the secondary coils (18) on both sides thereof are fixed to the inner peripheral surface of the gearbox cylindrical part (31). ) has a built-in steering angle detector (11), but a similar structure is possible for the rear wheels as well.

In this way, the steering angle detector (11) is installed inside the gear box (3).
This arrangement is advantageous in terms of space and allows the coils (15) and (1B) to be supported using the gearbox (3) without using a bracket.

By the way, the formation of the core (14) is shown in FIGS. 6(a) to (f).
) Various structures are possible. That is, the same figure (a
), the rack shaft (4) is simply provided with a large diameter portion (12), and as shown in FIG.
12) with metal 1i:1 (13), (13) on both sides, and a large diameter metal ring (17) around the rack shaft (4) as shown in (C) of the same figure. As shown in (d), the rack shafts (4) on both sides of the large diameter part (12) J,! Coating (1g) and (18) on it, same figure (e)
Rack shaft (with a groove on the 0th circumference and a metal ring of the same diameter (19
), coatings (18), (18
).

Here, the rack shaft (4) of the type shown in FIG. 6(a) in which only the large diameter portion (12) is provided receives signals from the circumference of the rack shaft (4) itself other than the large diameter portion (12). Therefore, unless the large diameter part (12) is made thicker than the rear shaft (4), it will be difficult to get a clear signal, and if it is made large, it will take up space and
There is also a major problem. On the other hand, if a large diameter core (14) is formed only from a non-magnetic metal ring (17) such as copper or aluminum as in the type (C) in the same figure, the non-magnetic metal absorbs magnetic lines of force as vortex TLIQ. Since the difference between the rack shaft and the metal is clearly visible, there is an advantage that a large output signal can be obtained. In particular, experiments have shown that the type shown in FIG. 6(C) has a larger signal than the types shown in FIGS. 6(a) and 6(b), and has the highest detection accuracy.

Next, an embodiment of a steering angle detector using the core of the type shown in FIG. 6(C) will be described.

FIG. 7 shows a schematic plan view of the active rear wheel #9 steering device of the fifth embodiment, where (27) is the knuckle, (28) is the rear wheel, and the rear wheel steering gear box (41) is similar to the above. The internal structure of is shown in FIG. That is, a screw shaft (43) is incorporated into the gear box (41) so as to be slidable in the width direction of the vehicle body.
The screw shaft (43) 1 in the gear box (41) is provided with a motor (51) and a steering angle detection W (111).

The pole screw (44) on the screw shaft (43) also has a pole (
45) The nut member (4B) is screwed through...
A cylindrical rotating shaft (52) is interlocked and connected to a nut member (4B) rotatably supported within the gear box (41). This rotating shaft (52) is arranged with a gap provided around the outer periphery of the screw shaft (43), and a plurality of iron cores (53) are fixed to the outer periphery of the rotating shaft (52) in the circumferential direction. An armature winding (54) is wound around the armature winding (54), and a permanent magnet (55) is further provided with a gap from the outer periphery of the iron core (53).
is fixed to the inner periphery of the cylindrical part (42) of the gear box (41), (58) is a commutator, (57) is a brush, and (58) is a brush holder.

A large-diameter metal ring (17) is provided around the screw shaft (43) near the motor (51) to form a core (14), and a gap is provided between the core (14) and the primary coil. (15
) and secondary coils (I8) and (18) lined up on its outer periphery are fixedly installed on the inner periphery of the gearbox cylindrical part (42), thereby forming the steering angle detector (111) of the type shown in FIG. 6(c). Configure.

When the NAND member (46) rotates due to the operation of the motor (51), the screw shaft (43) moves in the left-right direction by the pole screw mechanism, thereby steering the rear wheels (28) and changing the steering angle. Rear wheel steering information is detected by a detector (111).

In this way, the present invention is applicable not only to the rack and pinion type steering device but also to an electric pole screw mechanism type steering device, and although not shown, it can be mechanically connected to the front wheel steering device using an eccentric pin, a planetary gear mechanism, etc. The present invention can also be applied to a rear wheel steering device of the type that steers the rear wheels by moving the joint rod in the left and right directions. In short, the steering angle detector may be constructed by arranging a differential transformer on a rod member such as a roller shaft, a screw shaft, a joint rod, or a joint rod that outputs the steering angle to the wheels.

(Effects of the Invention) As described above, according to the present invention, since steering angle information is detected from the rod member that serves as the steering angle output member to the wheels by using a differential transformer, the steering angle information is detected from the rod member that outputs the steering angle to the wheels. Accurate steering angle information can be obtained without being affected.

[Brief explanation of the drawing]

Fig. 1 is a schematic plan view of a 4WS device showing the first embodiment, Fig. 2 is a perspective sectional view of the steering angle detector, and Figs. 3 and 4 show the second and third embodiments, respectively. 5 is a schematic plan view of the 4WS device, FIG. 5 is a broken rear view of the main part of the steering gear box showing the fourth embodiment, FIGS. 6(a) to 6(f) are front views showing an example of the structure of the core, 7 and 8 are a schematic plan view of a rear wheel steering device and a cross-sectional view of the inside of its gear box, showing a fifth embodiment. In the drawings, (4), (2B), and (43) are rod members, and (11). (111) is the steering angle detector, (12) is the large diameter part, (13)
, (17). (19) is a metal ring, (14) is a core, (15), (1
6) is a coil. Patent applicant: Agent for Honda Motor Co., Ltd.
Patent Attorney Part 2 1) Patent Attorney at the Department of Technology Kuni Ohashi, Patent Attorney at the Department
Yuki Koyama Patent Attorney No 1)
Figure 1 Figure 2 Figure 3 Figure 4 Figure 6

Claims (1)

[Scope of Claims] A steering angle detection system comprising a metal core provided on a bar member that moves in the width direction of the vehicle body by steering, and a primary coil and a secondary coil provided at a distance from each other around the outer periphery of the core. vessel.