JP2014061752A - Door mirror device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a door mirror device for a vehicle which can reduce a sense of incongruity given to a driver while ensuring a wide angle of view.SOLUTION: In a door mirror device (6) for a vehicle, which is mounted to doors (2, 4) of a vehicle (1) and has reflecting mirrors (8), the reflecting mirrors (8) each includes a curvature radius constant region (12) which exists inside the vehicle width direction and has a constant curvature radius, and a curvature radius change region (14) which exists outside the vehicle width direction and whose curvature radius is stepwisely reduced toward the outside in the vehicle width direction. The angle of view of the reflecting mirror (8) is 30° or more, the curvature radius of the curvature radius constant region (12) is 1.3 m or more, and the curvature radius of the curvature radius change region (14) at the outside end in the vehicle width direction is 0.3 m or more.

Description

  The present invention relates to a vehicle door mirror device that is attached to a vehicle door and includes a reflecting mirror.

  Conventionally, in order to secure a field of view behind the vehicle, a vehicle door mirror device having a reflecting mirror directed toward the rear of the vehicle has been used. In recent years, in order to increase the field of view behind the vehicle (mirror angle of view) without increasing the size of the vehicle door mirror device itself, a convex mirror having a smaller radius of curvature than that of the inner portion of the reflector in the vehicle width direction outer portion. A compound curvature mirror formed as follows may be used.

  For example, Patent Document 1 discloses that a reflecting mirror of a door mirror device includes a constant curvature portion having a substantially constant curvature radius of the mirror surface, and a gradual decrease in the curvature radius of the mirror surface that continues to the constant curvature portion and gradually decreases toward the end portion. A vehicle indirect visual recognition device provided with an inflection part is disclosed. Is this indirect visual recognition device provided with a polarizing film in the constant curvature portion and provided with a color filter in the gradual curvature portion, whether the visual recognition is through the constant curvature portion of the mirror surface or is visible through the gradual curvature portion? Can be easily determined.

JP 2008-174219 A

  By the way, when the reflecting mirror of the door mirror device is a plane mirror or a convex mirror with a constant curvature radius, the shape of the object reflected on the reflecting mirror is the same when viewed from the right eye and when viewed from the left eye. An object reflected on the reflecting mirror can be stereoscopically viewed as one object.

  However, in the compound curvature mirror such as the reflection mirror of the door mirror device of Patent Document 1 described above, the curvature radius of the reflection mirror varies along the vehicle width direction, so that an object when viewed from the right eye is a reflection mirror. Depending on the difference between the reflected position and the position where the object viewed from the left eye is reflected on the reflecting mirror (that is, the difference in the proportion of the mirror image of the object that is reflected in the slowly varying curvature part), the convex mirror reflects the mirror image of the object. The degree to which the width is compressed is different. As a result, the shape of the object reflected on the reflector differs between when viewed from the right eye and when viewed from the left eye, so the driver cannot stereoscopically view the object reflected on the reflector as a single object, which may cause discomfort. There is.

  The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide a vehicle door mirror device that can reduce a sense of incongruity given to a driver while ensuring a wide angle of view. .

In order to achieve the above object, a vehicle door mirror device according to the present invention is a vehicle door mirror device that is attached to a vehicle door and has a reflecting mirror. The reflecting mirror is on the inner side in the vehicle width direction and has a constant radius of curvature. An area having a constant radius of curvature and an area having a radius of curvature that is stepwise outward in the vehicle width direction and gradually decreases toward the outside in the vehicle width direction, and the angle of view of the reflector is 30 ° or more, The curvature radius of the curvature radius constant region is 1.3 m or more, and the curvature radius at the outer end in the vehicle width direction of the curvature radius change region is 0.3 m or more.
In the present invention configured as described above, by setting the curvature radius at the outer end in the vehicle width direction to 0.3 m or more, when viewed from the right eye, the field angle of the object reflected in the curvature radius change region and the left eye are viewed. In this case, the difference between the angle of view of the object reflected in the radius-of-curvature change area is effectively reduced, and the discomfort caused by the shape of the object reflected on the reflector is different between when viewed from the right eye and when viewed from the left eye. Therefore, it is possible to reduce a sense of discomfort given to the driver while ensuring an appropriate distance to the object reflected on the reflecting mirror and a necessary mirror angle of view.

In the present invention, preferably, the length in the vehicle width direction of the curvature radius changing region is 0.05 m or more.
In the present invention configured as described above, the mirror angle of view of the reflecting mirror can be maintained at a relatively large value, and both reduction of the uncomfortable feeling given to the driver and securing of the necessary mirror angle of view can be achieved. it can.

In the present invention, it is preferable that the number of steps in which the curvature radius of the curvature radius change region decreases is 10 or less.
In the present invention configured as described above, the mirror angle of view of the reflecting mirror can be maintained at a relatively large value, and both reduction of the uncomfortable feeling given to the driver and securing of the necessary mirror angle of view can be achieved. it can.

In the present invention, it is preferable that the decreasing rate of the curvature radius in the curvature radius changing region decreases toward the outside in the vehicle width direction.
In the present invention configured as described above, the mirror angle of view of the reflecting mirror can be maintained at a relatively large value, and both reduction of the uncomfortable feeling given to the driver and securing of the necessary mirror angle of view can be achieved. it can.

  According to the vehicle door mirror device of the present invention, it is possible to reduce a sense of discomfort given to the driver while ensuring a wide angle of view.

1 is a plan view of a vehicle having a vehicle door mirror device according to an embodiment of the present invention. It is a top view of the door mirror device for vehicles by the embodiment of the present invention. It is sectional drawing in the III-III line of FIG. 2 of the reflecting mirror with which the vehicle door mirror apparatus by embodiment of this invention is provided. It is a diagram which shows the curvature radius of the reflective mirror with which the vehicle door mirror apparatus by embodiment of this invention is provided. FIG. 5A is a plan view of the vehicle door mirror device, FIG. 5A is a diagram showing the vehicle door mirror device viewed from the driver's left eye, and FIG. 5B is a vehicle door mirror device viewed from the driver's right eye. FIG. It is a diagram which shows the change of the feature point shift | offset | difference excess amount according to the change of each parameter which determines the shape of a reflective mirror. FIG. 7A is a diagram showing a change in the mirror angle of view of the reflecting mirror in accordance with a change in each parameter that determines the shape of the curvature radius change region, and FIG. 7A shows a change in the length L _Rchg of the curvature radius change region. FIG. 7B is a diagram showing a change in the mirror angle of view θ, and FIG. 7B is a diagram showing a change in the mirror angle of view θ according to a change in the decrease rate r _{crv in which} the radius of curvature of the curvature radius change region decreases. (C) is a diagram showing the change of the mirror angle of view θ according to the change of the number of steps N _{div in which} the radius of curvature of the curvature radius change region decreases.

Hereinafter, a vehicle door mirror device according to an embodiment of the present invention will be described with reference to the accompanying drawings.
First, the configuration of a vehicle door mirror device according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a plan view of a vehicle having a vehicle door mirror device according to an embodiment of the present invention, FIG. 2 is a plan view of the vehicle door mirror device according to an embodiment of the present invention, and FIG. FIG. 4 is a cross-sectional view taken along line III-III of FIG. 2 of the reflector provided in the vehicle door mirror device according to the embodiment, and FIG. 4 is a diagram showing the radius of curvature of the reflector provided in the vehicle door mirror device according to the embodiment of the present invention. It is.

  As shown in FIG. 1, a vehicle door mirror device 6 is provided at each of the front end of the left front door 2 and the front end of the right front door 4 of the vehicle 1. The vehicle door mirror device 6 includes a mirror stay 6a that is fixed to the front doors 2 and 4 of the vehicle, and a housing 6b that is rotatably attached to the mirror stay 6a. A reflecting mirror 8 directed to the rear of the vehicle 1 is attached to the housing 6b. The driver can visually recognize the rear of the vehicle 1 indirectly by looking at the reflecting mirror 8. A mirror field angle at which the driver can visually recognize the rear through the reflecting mirror 8 is defined as θ. In order to ensure a sufficient rear field of view for the driver, it is desirable to set the mirror angle of view θ to a predetermined value or more (for example, 30 ° or more).

As shown in FIGS. 2 and 3, the reflecting mirror 8 includes a constant radius of curvature region 12 formed on the inner side in the vehicle width direction from a boundary line 10 extending vertically at a predetermined position in the vehicle width direction of the reflecting mirror 8, and a boundary A radius-of-curvature changing region 14 formed on the outer side in the vehicle width direction from the line 10.
The constant curvature radius region 12 is formed as a convex mirror having a constant curvature radius R _main . The smaller the radius of curvature R _main is, the larger the angle of view θ of the reflecting mirror 8 can be. However, since the distortion of the object reflected on the reflecting mirror 8 increases, the driver needs to know the sense of distance to the object. Becomes difficult. Therefore, it is desirable that the radius of curvature R _main is set to a predetermined value or more (for example, 1.3 m or more) so that the driver can appropriately grasp the distance to the object reflected on the reflecting mirror 8.

On the other hand, the curvature radius changing region 14 is formed as a convex mirror whose curvature radius decreases stepwise toward the vehicle width direction outer side.
The shape of the curvature radius changing region 14 is such that the length L _Rchg of the curvature radius changing region 14 (that is, the length from the boundary line 10 of the reflecting mirror 8 to the outer end in the vehicle width direction) and the curvature radius of the curvature radius changing region 14 are as _follows. Decrease number of steps N _div , decrease rate r _{crv at which} the radius of curvature of the curvature radius change region 14 decreases, and curvature radius (end curvature radius) R _end at the outer end in the vehicle width direction of the curvature radius change region 14 .
As shown in FIG. 4, when the length along the tangent in the horizontal direction in contact with the reflecting mirror 8 at the center (mirror center) C in the vehicle width direction of the reflecting mirror 8 is set as the mirror horizontal length L, as shown in FIG. Further, the curvature radius of the curvature radius changing region 14 is set to a constant mirror horizontal length (L _Rchg / N _div ) from the curvature radius R _main of the constant curvature radius region 12 to the terminal curvature radius R _end of the curvature radius changing region 14. Decrease gradually.
The decreasing rate r _crv at which the curvature radius of the curvature radius changing region 14 decreases is the curvature radius when the curvature radius of the curvature radius changing region 14 decreases with a certain inclination (that is, the curvature radius decreases linearly in FIG. 4). R _crv = (R _m −R _end ) / (R where R _{0 is} the radius of curvature in the center of the vehicle width direction of the change region 14 and R _m is the radius of curvature of the center of the change radius region 14 in the vehicle width direction. ₀ −R _end ). In the example of FIG. 4, since R ₀ = 1100 mm, R _m = 650 mm, and R _end = 200 mm, the reduction rate r _crv = (650−200) / (1100−200) = 0.5.

Next, referring to FIG. 5, a method for evaluating a sense of incongruity caused by the shape of the object reflected on the reflecting mirror 8 being different between when viewed from the right eye and when viewed from the left eye will be described.
FIG. 5 is a plan view of the vehicle door mirror device 6, FIG. 5 (a) is a diagram showing the vehicle door mirror device 6 viewed from the driver's left eye, and FIG. 5 (b) is from the driver's right eye. It is the figure which shows the door mirror apparatus 6 for vehicles which looked.

Since the position at which the object is reflected on the reflecting mirror 8 differs depending on whether the object is viewed from the right eye or the left eye, the proportion of the portion of the mirror image of the object that is reflected in the curvature radius change region 14 is different. As a result, the angle of view of the object reflected in the curvature radius changing region 14 differs between when viewed from the right eye and when viewed from the left eye.
In the example of FIG. 5, the mirror image of the rear vehicle 16 is more visible when viewed from the driver's right eye (FIG. 5B) than when viewed from the driver's left eye (FIG. 5A). Since the ratio of the portion reflected in the curvature radius change region 14 is large, the degree to which the mirror image is compressed becomes large. Therefore, the angle of view of the rear vehicle 16 reflected on the reflecting mirror 8 is narrower when viewed from the driver's right eye than when viewed from the driver's left eye.
Here, the angle of view between the left and right headlights of the rear vehicle 16 reflected on the reflector 8 when viewed from the left eye of the driver is θ _l , and the rear vehicle 16 reflected on the reflector 8 when viewed from the right eye of the driver. If the angle of view between the left and right headlights is θ _r , the difference between these angles of view θ _d = θ _l −θ _r is defined as the “feature point deviation amount”. When this feature point deviation amount θ _d is less than a predetermined reference value T, the driver can stereoscopically view the rear vehicle 16 reflected on the reflecting mirror 8 as one object. However, when the feature point deviation amount θ _d becomes equal to or greater than the predetermined reference value T, the driver cannot stereoscopically view the rear vehicle 16 reflected on the reflecting mirror 8 as one object, and the feature point deviation amount θ _d is further reduced. The larger the feeling, the greater the uncomfortable feeling that the driver feels. That is, by reducing the feature point deviation amount θ _d , it is possible to reduce the uncomfortable feeling given to the driver. More specifically, the amount of feature point deviation θ _d exceeding a predetermined reference value T (feature point deviation excess amount) G is set to 4.5 ° or less, so that the driver feels uncomfortable within an allowable range. Can be suppressed.

The inventors of the present invention use each of the mirror angle of view θ and the feature point deviation amount G of the reflecting mirror 8 as a target variable, and the curvature radius R _main of the constant curvature radius region 12 and the length L _Rchg of the curvature radius change region 14. The number of steps N _{div at which} the curvature radius of the curvature radius change region 14 decreases, the decrease rate r _{crv at which} the curvature radius of the curvature radius change region 14 decreases, and the terminal curvature radius R _end of the curvature radius change region 14 are explanatory variables. By performing multivariate analysis (for example, multiple regression analysis), the following equations were derived.
... (1)
... (2)

Next, a method for determining the shape of the curvature radius changing region 14 will be described with reference to FIGS.
FIG. 6 is a diagram showing a change in the feature point deviation excess amount according to a change in each parameter that determines the shape of the reflecting mirror 8 of the vehicle door mirror device 6. FIG. 7 is a diagram showing changes in the mirror angle of view of the reflecting mirror 8 in accordance with changes in parameters that determine the shape of the radius-of-curvature changing region 14, and FIG. graph showing the change in the mirror angle θ corresponding to the change in length L _Rchg in FIG. 7 (b) mirror angle in response to changes in reduction rate r _crv radius of curvature of the curvature radius change region 14 is reduced graph showing the change in the theta, FIG. 7 (c) is a graph showing the change in the mirror angle theta in response to changes in number of levels N _div radius of curvature of the curvature radius change region 14 is reduced.

FIG. 6 is a diagram illustrating the shape of the reflecting mirror 8 within the range of predetermined constraints such as the manufacturing constraints of the reflecting mirror 8 and the restrictions on the regulation of the vehicle door mirror device 6 in the above-described formula (2). A change in the feature point deviation excess amount G when the parameter is changed is shown. As shown in FIG. 6, the change in the feature point deviation excess amount G with respect to the change in the terminal curvature radius R _end is larger than the change in G with respect to other parameters. That is, in order to reduce the feature point deviation excess amount G in order to reduce the uncomfortable feeling given to the driver, it is considered most effective to increase the terminal curvature radius _Rend . In particular, by setting the _end curvature radius R _end to 0.3 m or more, the feature point deviation excess amount G can be suppressed to a sufficiently small value (that is, 4.5 ° or less).
However, as is clear from the above equation (1), when the end curvature radius _Rend is increased, the mirror angle of view θ is decreased. Therefore, the necessary mirror angle of view θ is secured by adjusting each parameter other than the terminal curvature radius R _end that determines the shape of the curvature radius change region 14.

FIG. 7 shows the change in the mirror angle of view θ when each parameter for determining the shape of the reflecting mirror 8 is changed within the range of the predetermined constraint in the expression (1).
As shown in FIG. 7A, the mirror angle of view θ is larger as the length L _Rchg of the curvature radius changing region 14 is longer regardless of the change in the terminal curvature radius R _end . In particular, the mirror angle of view θ can be maintained at a relatively large value by _setting the length L _Rchg of the curvature radius changing region 14 to 0.05 _m or more.
Further, as shown in FIG. 7B, regardless of the change in the terminal curvature radius R _end , the smaller the decrease rate r _{crv at} which the curvature radius of the curvature radius change region 14 decreases, the larger the mirror angle of view θ. In particular, by _setting the reduction rate r _crv to 0.6 or less, the mirror angle of view θ can be maintained at a relatively large value.
Further, as shown in FIG. 7C, the mirror angle of view θ is larger as the number of steps N _{div at} which the curvature radius of the curvature radius change region 14 decreases is smaller regardless of the change in the terminal curvature radius R _end . In particular, the mirror angle of view θ can be maintained at a relatively large value by setting the number of steps N _div to 10 or less.

For example, the curvature radius R _main of the constant curvature radius region 12 is 1.3 m or more, the end curvature radius R _end is 0.3 m or more, the length L _Rchg of the curvature radius change region 14 is 0.05 m or more, and the curvature radius change region 14 When the decrease rate r _{crv at} which the radius of curvature of the _reflector decreases is 0.6 or less and the number of steps N _{div at} which the radius of curvature of the curvature radius change region 14 decreases is 10 or less, the mirror field angle θ of the reflector is 30 °. As described above, the feature point deviation excess amount G is 4.5 ° or less.

  Next, effects of the vehicle door mirror device 6 according to the above-described embodiment of the present invention will be described.

First, the mirror field angle θ of the reflecting mirror 8 is 30 ° or more, the curvature radius R _main of the constant curvature radius region 12 is 1.3 m or more, and the curvature at the outer end in the vehicle width direction of the curvature radius changing region 14 is first. Since the radius R _end is 0.3 m or more, the feature point deviation excess amount G can be suppressed to a relatively small value while ensuring an appropriate distance to the object reflected on the reflecting mirror 8 and a necessary mirror angle of view. It is possible to reduce the uncomfortable feeling given to the driver.

Further, since the vehicle width direction length L _{Rchg of the} curvature radius changing region 14 is 0.05 m or more, the mirror angle of view θ is maintained at a relatively large value even when the terminal curvature radius R _end is 0.3 m or more. It is possible to reduce both the feature point deviation excess amount G and secure the necessary mirror angle of view θ by setting the terminal curvature radius R _end to 0.3 m or more.

Further, since the number of steps N _{div at} which the curvature radius of the curvature radius change region 14 decreases is 10 or less, the mirror angle of view θ is maintained at a relatively large value even when the terminal curvature radius R _end is 0.3 m or more. It is possible to reduce both the feature point deviation excess amount G and secure the necessary mirror angle of view θ by setting the terminal curvature radius R _end to 0.3 m or more.

Furthermore, since the decreasing rate r _{crv at} which the curvature radius of the curvature radius changing region 14 decreases is 0.6 or less, the required mirror field angle θ is relatively large even when the terminal curvature radius R _end is 0.3 m or more. Therefore, it is possible to achieve both reduction of the feature point deviation excess amount G and securing of a necessary mirror angle of view θ by setting the terminal curvature radius R _end to 0.3 m or more.

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Left front door 4 Right front door 6 Vehicle door mirror device 6a Mirror stay 6b Housing 8 Reflector 10 Boundary line 12 Curvature radius constant area 14 Curvature radius change area 16 Rear vehicle

Claims (4)

In a vehicle door mirror device attached to a vehicle door and having a reflecting mirror,
The reflecting mirror is located on the inner side in the vehicle width direction and has a constant curvature radius region having a constant curvature radius, and on the outer side in the vehicle width direction, and the curvature radius changing region where the curvature radius decreases stepwise toward the outer side in the vehicle width direction. And comprising
The angle of view of the reflecting mirror is 30 ° or more, the curvature radius of the constant curvature radius region is 1.3 m or more, and the curvature radius at the outer end in the vehicle width direction of the curvature radius changing region is 0.3 m or more. A vehicle door mirror device characterized by the above.   The vehicle door mirror device according to claim 1, wherein a length in the vehicle width direction of the curvature radius changing region is 0.05 m or more.   The vehicle door mirror device according to claim 1 or 2, wherein the number of steps at which the curvature radius of the curvature radius changing region decreases is 10 or less.   4. The vehicle door mirror device according to claim 1, wherein a decreasing rate of the curvature radius of the curvature radius changing region decreases toward the outside in the vehicle width direction. 5.