Flexural vibration element and electronic component

1. A flexural vibration element comprises:

a vibration element body composed of a plurality of vibrating arms provided in parallel, a connecting part connecting the vibrating arms, and one central supporting arm extending between the vibrating arms from the connecting part in parallel with the vibrating arms at equal distance from the arms; and

a frame body disposed outside the vibration element body,

the vibration element body being supported by the frame body at an end part, the end part being opposite to the connecting part, of the central supporting arm,

the end part, opposite to the connecting part, of the central supporting arm being directly connected with one side part of the frame body so as to support the vibration element body, and

the side part of the frame body being connected with the central supporting arm and having a groove formed on at least one of a front surface and a rear surface thereof, and the groove being positioned in an area that is along the side part and in which compressive stress and tensile stress alternately occur at an inner side and an outer side in a width direction of the side part due to flexural vibration of the vibrating arms.

2. The flexural vibration element according to claim 1 , wherein the groove is formed between one end of the side part and a part of the same to which the central supporting arm is connected and between the other end of the side part and the part to which the central supporting arm is connected.

3. The flexural vibration according to claim 1 , wherein the groove has a bottom.

4. The flexural vibration element according to claim 1 ; wherein the groove is a through groove.

5. A flexural vibration element comprises:

a vibration element body composed of a plurality of vibrating arms provided in parallel, a connecting part connecting the vibrating arms, and one central supporting arm extending between the vibrating arms from the connecting part in parallel with the vibrating arms at equal distance from the arms; and

a frame body disposed outside the vibration element body,

the vibration element body being supported by the frame body at an end part, the end part being opposite to the connecting part, of the central supporting arm, the frame body having a supporting part, at an interior side thereof, extending between a pair of side parts thereof, and the end part, opposite to the connecting part, of the central supporting arm being connected to the supporting part so as to support the vibration element body.

6. The flexural vibration element according to claim 5 , wherein the supporting part has a groove formed on at least one of a front surface and a rear surface thereof, and the groove is positioned in an area that is along the supporting part and in which compressive stress and tensile stress alternately occur at a vibration element body side of the supporting part and an opposite side to the vibration element body side due to flexural vibration of the vibrating arms.

7. The flexural vibration element according to claim 6 , wherein the groove is formed between one end of the supporting part and a part of the same to which the central supporting arm is connected and between the other end of the supporting part and the part to which the central supporting arm is connected.

8. The flexural vibration element according to claim 6 , wherein the groove has a bottom.

9. The flexural vibration element according to claim 6 , wherein the groove is a through groove.

10. An electronic component, comprising:

the flexural vibration element of claim 1 ;

a base on which the flexural vibration element is disposed; and

a lid bonded with the base, wherein

the flexural vibration element is fixed to the base at a side part that is different from a side part to which the central supporting arm of the frame body is connected, and is air-tightly sealed in a space formed by the base and the lid.

11. An electronic component, comprising:

the flexural vibration element of claim 5 ;

a base bonded to a lower surface of the frame body of the flexural vibration element; and

a lid bonded to an upper surface of the frame body, wherein the flexural vibration element is air-tightly sealed in a space formed by the base and the lid.

12. An electronic component; comprising:

the flexural vibration element of claim 5 ;

a base on which the flexural vibration element is disposed; and

a lid bonded with the base; wherein the flexural vibration element is fixed on the base at a side part of the frame body, and the flexural vibration element is air-tightly sealed in a space formed by the base and the lid.

13. The flexural vibration element claim 1 , wherein the groove of the supporting part is a through groove.

14. An electronic component comprises:

the flexural vibration element of claim 1 ;

a base on which the flexural vibration element is disposed; and

a lid bonded with the base.

15. An electronic component comprises:

the flexural vibration element of claim 1 ;

a base bonded to a lower surface of the frame body of the flexural vibration element; and

a lid bonded to an upper surface of the frame body.

16. An electronic component, comprising:

the flexural vibration element of claim 5 ;

a base on which the flexural vibration element is disposed; and

a lid bonded with the base, wherein

the flexural vibration element is fixed to the base at a side part that is different from a side part to which the central supporting arm of the frame body is connected, and is air-tightly sealed in a space formed by the base and the lid.

17. An electronic component comprises:

the flexural vibration element of claim 5 ;

a base on which the flexural vibration element is disposed; and

a lid bonded with the base.

18. An electronic component comprises:

the flexural vibration element of claim 5 ;

a base bonded to a lower surface of the frame body of the flexural vibration element; and

a lid bonded to an upper surface of the frame body.