Battery holder for button-type battery

1. A battery holder for a battery having a circular side and flat surfaces, the battery holder made of an insulating material and comprising:

a case body having an upper wall and a side wall provided to a limb of the upper wall;

a base material arranged on an open side of the side wall of the case body such that space exists between the upper wall and the base material; and

an elastic first terminal and an elastic second terminal arranged in the space between the upper wall and the base material and provided on the base material,

wherein an opening as well as first and second preventive parts respectively opposite in a part of the limb of the opening are provided to the upper wall of the case body;

wherein the upper wall completely surrounds the opening,

wherein a circumferential wall corresponding to the circular side of the battery is provided in a vicinity of the second preventive part,

wherein a hole communicating with the space penetrates the side wall of the case body,

wherein the hole is located on a second preventive part side of the opening,

wherein the first terminal is provided opposite to the first preventive part,

wherein the second terminal is provided such that the second terminal faces the opening,

wherein the battery is inserted from the opening into the space,

wherein the first terminal is elastically touched to the circular side of the battery,

wherein the battery is pressed in a direction of the circular side opposite to the elastically touched circular side,

wherein the circular side is touched to the circumferential wall and the second terminal is elastically touched to one of the flat surfaces of the battery,

wherein the battery is pressed in a direction of the other of the flat surfaces of the battery,

wherein the other of the flat surfaces is touched to inner faces of the first and second preventive parts and the battery is housed in the space,

wherein when the battery housed in the space is extracted from the case body, the battery is moved against an elastic contact force of the first terminal via the hole of the side in the case body,

wherein prevention by the second preventive part is released, and

wherein the battery can be extracted from the opening of the case body.

2. The battery holder for a battery according to claim 1 ,

wherein a tongue piece is extended from the first preventive part to a substantial center of the opening, and

wherein a part of the other of the flat surfaces of the battery is held by the tongue piece.

3. The battery holder for a battery according to claim 2 , wherein the tongue piece is elastic.

4. The battery holder for a battery according to claim 1 , wherein the base material is a printed wiring board.

5. The battery holder for a battery according to claim 2 , wherein the base material is a printed wiring board.

6. The battery holder for a battery according to claim 3 , wherein the base material is a printed wiring board.

7. The battery holder for a battery according to claim 1 , wherein the side wall in which the hole is formed is disposed around the battery, and the hole communicates with the space from a side surface of the side wall.

8. The battery holder for a battery according to claim 1 , wherein a diameter of the hole is less than a distance between the base material and a bottom of the upper wall.

9. The battery holder for a battery according to claim 1 , wherein a diameter of the hole is about the same as a diameter of the circumferential wall.

10. The battery holder for a battery according to claim 1 , wherein the upper wall disposed above the hole is continuous.

11. The battery holder for a battery according to claim 2 , wherein the tongue piece is elastically deformed to increase an area of the opening when the battery is inserted.