Stereo camera device
The present invention provides a stereo camera device with which it is possible to prevent the deformation of a housing caused by a warp or strain imposed on a cover and a difference in the rate of increase of the temperature of the housing and the cover, as well as to reduce the size of the housing and to cut down component counts and assembly man-hours. In the present invention, fixing of a substrate and a housing together and fixing of a cover and the housing together are performed in common, and the substrate and the cover are fixed to the housing at the same (common) fixing point, whereby a warp or strain imposed on the cover and a difference in the rate of increase of the temperature of the housing and the cover are absorbed by an elastic body that is used for floating/fixing and is provided for the purpose of cancelling a difference in the amount of contraction and expansion caused by a difference in the coefficient of linear expansion of the substrate and the housing.
1. A stereo camera device, comprising:
first and second imaging units;
a housing that includes the first and second imaging units;
a substrate that receives signals from the first and second imaging units, and has a linear expansion coefficient different from a linear expansion coefficient of the housing;
a cover that houses the substrate in cooperation with the housing, and has a linear expansion coefficient different from the linear expansion coefficient of the substrate;
a first fixing portion that co-fastens the substrate and the cover to the housing by a first fixing member without an elastic body interposed between the cover and the first fixing member; and
a second fixing portion that co-fastens the substrate and the cover to the housing by a second fixing member with an elastic body interposed between the cover and the second fixing member,
wherein the elastic body is configured to cause elastic deformation or sliding between the substrate and the cover so as to be allowable even though the cover holds a slight displacement from the substrate, and
the first fixing portion is provided at a position closer to a central point of a line segment connecting the first imaging unit and the second imaging unit than the second fixing portion.
2. The stereo camera device according to claim 1 , wherein the first fixing portion and the second fixing portion are co-fastened such that the substrate is interposed between the housing and the cover.
3. The stereo camera device according to claim 2 , wherein
a circumferential or annular vertical wall portion is erected along a peripheral edge of the housing,
a circumferential or annular abutment surface portion facing an upper surface of the vertical wall portion is provided along a peripheral edge of the cover, and a circumferential or annular outer peripheral wall portion is erected along a peripheral edge of the abutment surface portion, and
the cover houses the substrate in cooperation with the housing by mounting a peripheral edge of the substrate on the upper surface of the vertical wall portion, causing the abutment surface portion to abut on the peripheral edge of the substrate, and externally inserting the outer peripheral wall portion into the vertical wall portion.
4. The stereo camera device according to claim 1 , wherein the first fixing portion is provided on a plane which passes through the central point and is perpendicular to the line segment.
5. The stereo camera device according to claim 1 , wherein the second fixing portion is provided on the first imaging unit side and the second imaging unit side with a plane which passes through the central point and is perpendicular to the line segment interposed therebetween.
6. The stereo camera device according to claim 1 , wherein the elastic body is made of rubber or resin having a function of allowing predetermined deformation and returning to a shape before deformation.
7. The stereo camera device according to claim 1 , wherein
a plurality of the second fixing portions is provided, and
among the plurality of second fixing portions, an elastic body of the second fixing portion provided at a position relatively far from the central point is configured such that the amount of deformation or the amount of sliding is larger than the amount of deformation or the amount of sliding of an elastic body of the second fixing portion provided at a position relatively close to the central point.
8. The stereo camera device according to claim 1 , wherein
the substrate is arranged between the first and second imaging units, rearward of the first and second imaging units, or at both the first and second imaging units, and
the housing and the cover are latched only by a hooking structure outside the first and second imaging units.
9. The stereo camera device according to claim 8 , wherein the hooking structure includes an engagement protrusion portion provided at a side end of the housing, and an engagement hole which is provided at a side end of the cover and into which the engagement protrusion portion is fitted.
10. The stereo camera device according to claim 9 , wherein
the engagement protrusion portion is provided in a reception recess portion provided at the side end of the housing, and
the engagement hole is bent at the side end of the cover and is erected, and is provided at a rising engagement surface portion fitted into the reception recess portion.