JPH08329133A - Method for positioning license plate - Google Patents

Abstract

PURPOSE: To automatically determine the position of a license plate matched with regulations (light distribution rule). CONSTITUTION: Since the illuminance of a regulated illuminance measuring point on a license plate illuminated by a lamp 23 is calculated by a CAD system and the calculated illuminance is compared with regulated illuminance to position the plate 21, the position of the plate 21 can be automatically determined only by simple key entry. Whether the fixing position P of the plate 21 is included within a area 42 satisfying all regulation references or not can be visually checked on a display 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a license plate positioning method suitable for use in, for example, motorcycles and four-wheeled vehicles.

[0002]

2. Description of the Related Art A license plate (registration certificate, license number tag, so-called license plate) of a motorcycle or the like is provided with a lamp so that the identification symbol (so-called number) on the license plate can be easily confirmed from the rear even at night. It is required by law (license plate light distribution standard) to be illuminated and to secure an illuminance above a certain level on the license plate.

[0003] In order to secure the illuminance according to this regulation, conventionally, in the development and design stage of a motorcycle or the like, specifications of a lamp for illuminating a license plate (luminance specifications, etc.)
The position of the license plate with respect to the lamp was determined by manual calculation on the desk based on the regulations and the specifications (minimum illuminance specifications, etc.).

[0004]

However, since the size of the license plate and the light distribution standard of the license plate differ depending on the country, for example, Japan, the United States, Germany, etc., in the above-mentioned manual calculation method, the so-called destination is different. However, there is a problem in that it has to be calculated each time and the design man-hours are considerably increased.

Moreover, the lamp and the license plate have a relationship in which the axis of the lamp and the axis of the license plate coincide with each other in order to improve the visibility from the rear, in other words, the front surface of the license plate is illuminated by the lamp. Since it is not, the calculation was troublesome.

In addition, in practice, a design is manually performed to some extent as a guideline, and finally a light distribution test by an actual machine is performed to determine the position of the license plate that satisfies the regulation (light distribution standard). Since this was an indispensable task, it resulted in repeated trial and error and took time.

The present invention has been made in view of the above problems, and provides a license plate positioning method capable of automatically determining the position of the license plate conforming to the regulations (light distribution standard). The purpose is to do.

[0008]

SUMMARY OF THE INVENTION The present invention utilizes the CAD system to position the license plate in relation to a lamp that illuminates the license plate, as a CAD element, the dimensions of the license plate, and the license. The process of inputting the specifications of the lamp for illuminating the plate, the process of setting the illuminance measurement point on the license plate determined according to the law on the license plate, the filament position of the lamp and the license plate The step of inputting the initial mounting position, the step of calculating the calculated illuminance on the illuminance measurement point illuminated by the lamp, and the calculated illuminance calculated and the illuminance on the regulation are compared, and And a step of performing positioning.

Further, the invention is characterized in that, in the step of performing the positioning, a range satisfying the illuminance according to the regulation is displayed on the screen.

[0010]

According to the present invention, the CAD system calculates the calculated illuminance of the illuminance measurement point on the license plate illuminated by the lamp and compares the calculated illuminance with the illuminance on the law. Since the position of the license plate is determined, the position of the license plate can be automatically determined by a simple key input.

Further, according to the present invention, since the range satisfying the legal illuminance is displayed on the screen, it is possible to easily confirm whether or not the light distribution satisfies the rule.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a CAD to which this embodiment is applied.
1 shows a schematic configuration of the system 11.

As is well known, the CAD system 11 has a computer 12 as a control means. The computer 12 is a central processing unit (CPU) 13, an internal storage device, and is a random storage device for temporarily storing processed data. An access memory (RAM) 14, a read-only memory (ROM) 15 in which a system program and the like are written are provided.

The CPU 13 has a role of figure calculation, display control, database management and the like. A database 16 such as a hard disk, which is an external storage device, is connected to the CPU 13, and the database 16 includes a license plate light distribution standard in accordance with laws and regulations described later and other C
Information and the like corresponding to the drawing of the AD element are stored.

The CPU 13 is also an output device,
A display 17 comprising a CRT or the like as a central device for user interaction, a keyboard 18 which is an input device for characters and numerical values, and other well-known digitizers and joysticks for performing graphic input, display / program switching, etc. An input device 19 such as a dial, a function key, etc. is connected.

FIG. 2 shows a license plate 21 mounted on a rear wheel cover of a motorcycle (not shown).
And the surface of the license plate 21 (number, letters,
(A surface on which characters such as figures are formed by painting, etc.)
Shows a general positional relationship with a lamp (also referred to as a license light) 23 for illuminating the. In addition,
The graphic of FIG. 2 can be displayed on the display 17.

In FIG. 2, reference numeral 24 is a lamp cover made of a light transmissive member such as acrylic resin. The lamp cover 24 has a structure that substantially seals the lamp 23 together with a lamp holding portion (not shown), and has a lens function as necessary. The lamp 23, the lamp cover 24, and the lamp holding portion (not shown) are integrally configured to form the covered lamp 25. The cover-equipped lamp 25 is attached near the tip of a rear seat (not shown).

As is well known, the lamp 23 is composed of a cover portion such as glass for covering the filament 26 (reference numeral 26 is also used as a filament position) and a base portion for forming electrodes.

The lamp 23 is the license plate 2
There are two types of motorcycles, one is a motorcycle that is installed only for lighting and the other is a motorcycle that also serves as a tail light. However, the present invention is applicable to both types. Further, as described above, the present invention can be applied not only to motorcycles but also to four-wheeled vehicles.

Next, referring to the flowchart of FIG.
The operation of the above embodiment will be described in detail. The control subject is the CPU 13.

Usually, the license plate 2 is used at the final stage of motorcycle design and frame design.
The mounting position of 1 is officially determined.

Therefore, in such a stage, first,
The initial mounting position Pi of the license plate 21, the destination or model of the license plate 21, the mounting angle φ of the license plate 21 (see FIG. 2), and the specifications of the lamp 23 are input (step S1).

Here, the initial mounting position Pi is, as shown in FIG. 2, coordinates (DX, DY) from the filament position 26 of the lamp 23 to the central position of the upper end (upper side) 31 of the rectangular license plate 21. Specify with. In addition,
In practice, about 6 types of specifications (dimensions, luminous intensity, etc.) of the lamp 23 are stored in the CAD system 11 as default values in advance, so that it is not actually necessary to input the specifications of the lamp 23.

The destination of the license plate 21 is “domestic” and “US” as shown in the license plate light distribution standard table 40 shown in FIG. 4, and is not shown because it is complicated. However, for example, there are ECE ratification countries such as Switzerland and the Netherlands, and Germany.

Further, the type K of the license plate 21
1, K2, and A are determined in relation to the displacement amount shown in the division column. However, in the case of the United States, there is no need to enter the model because the divisions are not divided. Laws (light distribution standards) such as minimum illuminance are determined according to this model.
In fact, entering the model makes it unnecessary to specify the destination.

Next, based on the input of the model, whether the mounting angle φ (see FIG. 2) of the license plate 21 is within the standard, and the minimum incident angle θmin (of the light emitted from the lamp 23 to the license plate 21 I will explain later.)
It is determined by searching the license plate light distribution standard table 40 (step S2). here,
The incident angle θ is different from the usual optical incident angle, and as shown in FIGS. 2 and 5, the incident light ray L incident from the filament position 26 on the incident point Ip on the license plate 21 and the incident light L. It is defined as the angle formed by the sine of the ray L on the license plate 21. Minimum incident angle θm
“In” means the incident angle θ when the left and right ends 32R and 32L of the lower end (lower side) 32 of the license plate 21 are considered as the incident points Ip.

If the determination in step S2 is not established,
The calculated minimum incident angle θmin is displayed on the display 17 (step S3), and the plate mounting angle φ and the like are prompted again (step S1 again).

When the determination in step S2 is established,
Next, the light distribution value at the measurement points (predetermined illuminance measurement plate measurement points) described in the bottom column of the license plate light distribution standard table 40 shown in FIG. 4, that is, the illuminance I, In addition, the degree of uniformity (described later) is calculated and displayed on the screen of the display 17 (step S).
4). The measurement point is, for example, a license plate 21 having a size of 170 mm × 100 mm of a domestic model K1
In Fig. 4, there are 6 points indicated by ○.

In this case, the illuminance I at any point on the license plate 21 can be calculated by the following equation (1).

I = Γ × Q × sin θ / L ² (1) Here, Q: luminous intensity of the lamp [cd] Γ: 0.92 when the lamp cover 24 as a lens is an acrylic resin, and when it is a polycarbonate resin Is 0.8
9 θ: Incidence angle (see FIGS. 2 and 5) Next, it is determined whether the illuminance I or the like calculated in step S3 satisfies the reference value (step S4). Here, the reference value is the license plate light distribution standard table 4 in FIG.
0 is the minimum illuminance, the average illuminance, the proportion, and the like. In addition,
In the case of Europe, the brightness gradient is also included in the reference value.

As shown in the license plate light distribution standard table 40, the uniformity ratio has a different calculation formula depending on the model, and basically, the illuminance difference between the measurement point with low illuminance and the measurement point with high illuminance is constant. It is a standard to show whether it is within the range. The brightness gradient is determined based on whether or not a value obtained by dividing the brightness difference between two adjacent points by the distance between the two points is, for example, twice the minimum illuminance or less.

If it is determined in step S5 that the standard values of the laws and regulations are not satisfied, the area of the position of the license plate 21 that satisfies all the law and regulations is displayed on the display 17 in the positional relationship with the license plate 21. The area 42 is displayed as shown in FIG. 6 (step S6). A region 42 indicated by a hatched portion is a region that satisfies all legal standards.

Therefore, in this case, the license plate 21 is arranged in the area 42 so that the mounting position P of the license plate 21, which is defined as the center position of the upper end of the license plate 21, is set in the area 42, that is, in the hatching. It is sufficient to move in the direction, for example, the arrow Q direction (step S1 again). The coordinates P (DX, DY) of the mounting position P of the license plate 21 is the area 4
It is also possible to make the license plate 21 colored or change its color when the number is doubled to facilitate the confirmation.

After this second movement of the mounting position P, the mounting angle φ of the license plate 21 (see FIG. 2) is taken into consideration in terms of rear visibility and design.
If you want to change
The position of the license plate 21 can be determined by repeating the above process until the determination in step S5 is satisfied.

If the area 42 satisfying all the legal standards displayed in step S6 is structurally or design inappropriately, for example, too close to the position of the lamp cover 24, the CAD is concerned. When the user of the system 11 makes a decision, the lamp 23 is changed to a lamp 23 having higher luminous intensity (step S1), and steps S1 to S1 are performed.
The process of step S6 may be repeated.

FIG. 7 shows a state in which the license plate 21 has entered an area 42 that satisfies all the legal standards. This completes the positioning process of the license plate 21. In FIG. 7, reference numeral 41 is an area used when laying out the vehicle body design, specifically, an area for confirming, for example, interference between the license plate 21 and a vehicle body portion (not shown).

After positioning, the lamp with cover 25
The registered position of the license plate 21 and the confirmation area 41 as required are registered in the CAD system 11 (step S7). It is a so-called CAD element.

Finally, the light distribution value such as the illuminance value at each measurement point and the area where the emitted light L of the covered lamp 25 illuminates the license plate 21 is displayed and confirmed (step S8). . In this case, the reference value is also displayed. Required data among the created data is stored in the database 16.

As described above, according to the above-described embodiment, the CAD
The system 11 calculates the calculated illuminance of the illuminance measurement point on the license plate 21 illuminated by the covered lamp 25, and compares the calculated illuminance with the illuminance on the law to position the license plate 21. Since this is done, it is possible to obtain the effect that the position of the license plate 21 can be determined almost automatically simply by performing a simple key input with the keyboard 18 or the like.

In other words, there is an advantage that an appropriate layout of the license plate 21 and the covered lamp 25 for illuminating the license plate 21 can be easily set.

Further, according to the above-described embodiment, since the area 42 satisfying all the legal standards can be displayed on the display 17, it is possible to easily visually confirm whether or not the light distribution satisfies the legal. it can.

The present invention is not limited to the above embodiment,
It goes without saying that various configurations can be adopted without departing from the gist of the present invention.

[0044]

As described above, according to the present invention, the CAD system calculates the calculated illuminance at the illuminance measurement point on the license plate illuminated by the lamp on the legal plate, and the calculated illuminance and the legal plate are calculated. Since the license plate is positioned by comparing with the illuminance of, the effect that the position of the license plate can be automatically determined by a simple key input is achieved.

Further, according to the present invention, since the range satisfying the legal illuminance is displayed on the screen, it is possible to easily confirm whether or not the light distribution satisfies the rule. To be achieved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a CAD system to which an embodiment of the present invention is applied.

FIG. 2 is a diagram provided for explaining a relative position of a lamp and a license plate and the like.

FIG. 3 is a flowchart provided for explaining the processing of the example in FIG.

FIG. 4 is a diagram showing a license plate light distribution standard table.

FIG. 5 is a diagram provided for explaining a minimum incident angle and the like.

FIG. 6 is a diagram provided for explaining a state in which the region that satisfies all the legal standards and the position of the license plate do not match.

FIG. 7 is a diagram provided for explaining a state in which a region satisfying all the legal standards and the position of the license plate match.

[Explanation of symbols]

11 ... CAD system 12 ... Computer 13 ... CPU 16 ... Database 21 ... License plate 23 ... Lamp 24 ... Lamp cover 25 ... Covered lamp 26 ... Filament position 41 ... Confirmation area 42 ... Area satisfying all legal standards Ip ... Incident Point (illumination point) θ… Incident angle φ… Mounting angle

Claims (2)

[Claims] 1. A relation between a license plate and a lamp for illuminating the license plate. When positioning the license plate using a CAD system, the dimensions of the license plate and specifications of the lamp for illuminating the license plate are used as CAD elements. And a step of setting an illuminance measurement point on the license plate determined on the license plate on the license plate, and a filament position of the lamp and an initial mounting position of the license plate. A step of calculating a calculated illuminance on the illuminance measurement point illuminated by the lamp, and a step of positioning the license plate by comparing the calculated illuminance with the illuminance on the regulation. A method for positioning a license plate, comprising: 2. The method of positioning a license plate according to claim 1, wherein in the step of performing the positioning, a range satisfying the illuminance according to the law is displayed on the screen.