JPH0629417A - Sensor board - Google Patents

Abstract

PURPOSE:To reduce a high stress applied on an image sensor, a coupling part between the image sensor and a sensor board, and the sensor board by cantilevering the sensor board to which a sensor holder including the image sensor held thereon is fixed. CONSTITUTION:An image sensor 2 and a sensor board 4 are soldered to each other with the use of a jig, and the image sensor 2 is fixed to a sensor holder 1 using a leaf spring 3, and further the sensor holder 1 and the sensor board are fixed to each other through a screw 5. Thereupon, once the image sensor 2 and the sensor holder 1 are completely fixed to each other. There is applied force W which pulls down the sensor board 4, through the soldered portion. A portion of the sensor board 4 where the sensor board 4 is fixed to the sensor holder 1 through the screw 5 is cantilevered, whereby a load to the image sensor 2 due to a load to the image sensor 2 due to deflection of the sensor board 4 is sharply reduced without depending on the pitch L2 of the screw 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sensor board in which image sensors are connected, and a sensor holder to which an image sensor is held by a fixing means is fixed.

[0002]

Conventionally, in the sensor board in which the image sensor is connected to the sensor board, the sensor board in which the image sensor is held by the fixing means is fixed in the sensor board. The distance from the sensor to the sensor board is fixed. Further, since the sensor holder and the sensor board are fixed by the fixing means, the distance between the sensor holder and the sensor board is also decided.

Therefore, the above two distances do not match due to the dimensional tolerance of the sensor holder during processing and the assembly tolerance when the sensor is soldered, and a high load is applied to the image sensor and the connecting portion between the image sensor and the sensor board and the sensor board. This may damage the image sensor, the connection between the image sensor and the sensor board, and the sensor board. Improvement in this respect is desired.

[0004]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention is directed to a sensor board in which image sensors are connected, and a portion of the sensor board to which a sensor holder in which the image sensor is held by a fixing means is fixed. Provides a cantilevered structure.

[0005]

Therefore, according to the present invention, by taking the above means, in the sensor board to which the image sensor is connected, the part of the sensor board to which the sensor holder held by the image sensor or the fixing means is fixed is It has a cantilever shape, and can alleviate a high load on the image sensor and the connecting portion between the image sensor and the sensor board and the sensor board.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The image sensor 2 and the sensor holder 1 have the structure shown in FIG. First, the image sensor 2 and the sensor board 4 are soldered using a jig. In this case, the dimensional tolerance of the distance A between the bottom surface of the image sensor 2 and the bottom surface of the sensor board 4 can be empirically ensured to be ± 0.3 mm by using the jig.

Next, the image sensor 2 is fixed to the sensor holder 1 with the leaf spring 3, and the sensor holder 1 and the sensor board 4 are fixed with screws 5. The dimensional tolerance of the distance B from the abutting surface of the sensor holder 1 with the sensor board 4 to the abutting surface of the sensor board 4 is within ± 0.2 mm due to the processing accuracy. From A and B, this mounting tolerance is about ± 0.5 mm.

That is, when the image sensor 2 and the sensor holder 1 are completely fixed, a force W pulling the sensor board 4 downward through the soldering portion works. The relationship between this force W and the pitch L _{1 of the} screw 5 is as shown in FIG. When the sensor board 4 is fixed with the screws 5, it is considered as a statically indeterminate beam. In addition, L ₁ is limited to about 50 mm in terms of space.

Therefore, from the graph, the force W for pulling the sensor board 4 exceeds 100 kg. The Young's modulus E of the sensor board was E = 1470.5 kg / as a result of the measurement.
It was mm ² . Actually, the image sensor 2 is pulled by this force and cannot be fixed by the leaf spring 3, and even if it is possible, the soldered portion may be damaged.
Incidentally, the relationship between the load and the deflection when the both ends of the image sensor 2 can be fixed by the leaf springs 3 is shown in FIG. The Young's modulus E of the ceramic used is
E = 28543.01 kg / mm ² .

As a solution to the above problems, the structure of FIG. 4 was devised. According to this method, since each fixed part is a cantilever, the load on the image sensor 2 due to the deflection of the sensor board 4 does not depend on the pitch L _{1 of the} screw 5 and can be greatly reduced.

Mounting tolerance δ = 0.5 mm, sensor board 4
Thickness h = 1.6 mm, sensor board 4 Young's modulus E = 14
From 70.5 kg / mm ² , the relationship between the load W applied to the sensor board 4 and the notch length 1 is as shown in FIG. According to this graph, even if the cutout width B is about B = 10 mm, if the beam length 1 can be 1 = 20 mm, the load applied to the image sensor 2 is considered to be a concentrated load and is suppressed to 1 kg or less. To be With such a load, the image sensor 2 can be sufficiently fixed by the leaf spring 3.

When the above fixing method is performed, it is necessary to take into consideration the longitudinal deflection of the sensor board 4 and the image sensor 2.

If the sensor board 4 is fixed at four places and the pitch L _{1 in the} depth direction is L ₁ = 50 mm, the screw pitch L ₂ in the longitudinal direction in FIG.
The relationship with the pulling force W is as shown in FIG. 7 when the mounting tolerance δ = 0.5 mm. From the conventional width of the normal image sensor 2 (310 mm in the L ₂ direction), L ₂ is 20
Although it is 0 to 250 mm, even if it is considered as a static beam, it is W at the center
= A load of 0.3 kg or less is required.

FIG. 8 shows the relationship between the deflection W of the central portion of the image sensor 2 and the load W at this time.
According to this, even if the load W = 1 kg generated by the fixing in the depth direction is applied, the deflection δ of the image sensor 2
Is about 1 mm in the central part, but in reality, the part to be fixed at the distance of L ₂ is notched as described above, so W
The relationship of −L ₂ is different from that of the statically-determined beam, and since the plate springs 3 for fixing the image sensor 2 are also provided at three places, the above value is smaller than the notation.

[0015]

According to the sensor board of the present invention, it is possible to reduce a high load caused by processing and assembling precision, so that the image sensor and the connecting portion between the image sensor and the sensor board and the sensor board are prevented from being destroyed. Can be prevented.

[Brief description of drawings]

FIG. 1 is a sectional view of a mounting portion of an image sensor and a sensor holder.

FIG. 2 is a diagram showing a relationship between a force W for pulling the sensor board downward and a screw pitch L ₁ .

FIG. 3 is a relationship diagram of a load and a deflection when both ends of the image sensor can be fixed by leaf springs.

FIG. 4 is a perspective view showing an embodiment of the present invention.

FIG. 5 shows the relationship between the load W applied to the sensor board and the cutout length l in the sensor board of the present invention.

FIG. 6 is a positional relationship in the longitudinal direction of the image sensor.

FIG. 7 shows an example of the relationship between the screw pitch L _{2 in the} longitudinal direction of the image sensor and the force W pulling the image sensor. (Installation tolerance δ = 0.5mm)

FIG. 8: Deflection δ and load W at the center of the image sensor
An example of the relationship with.

[Explanation of symbols]

 1 ... Sensor holder 2 ... Image sensor 3 ... Leaf spring 4 ... Sensor board 5 ... Screw

Claims (1)

[Claims] 1. A sensor board to which an image sensor is connected, characterized in that a portion of the sensor board to which a sensor holder holding the image sensor by a fixing means is fixed has a cantilever shape. Sensor board.