JPH0445290Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention provides a holding terminal that holds a piezoelectric element used for a resonator, oscillator, filter, etc. at the vibration node point of the piezoelectric element from both sides. Regarding the structure of the board.

<Prior art> An electronic component using a piezoelectric element, such as a piezoelectric resonator, has a case 1o as shown in the cross-sectional view of FIG.
It has a piezoelectric element 2o which spreads inwards and has a vibration mode, and this piezoelectric element 2o is held by holding terminal plates 3o, 3o having spring elasticity at vibration node points of the vibration mode. These holding terminal plates 3o
As shown in the plan view of FIG. 7, the main plate portion 3oa
It has a structure in which the main plate part 3oa is integrally formed with the lead part 3ob, and a holding protrusion 4o is formed only at a portion that contacts the vibration node point of the piezoelectric element 2o at approximately the center of the main plate part 3oa.

<Problems to be Solved by the Invention> By the way, if the holding terminal plate 3o has the holding protrusion 4o only at the location corresponding to the vibration node point of the piezoelectric element 2o as described above, it is difficult to receive a strong external impact. If the piezoelectric element 2o tilts significantly relative to the holding terminal plate 3o as a result of this, the corner portion of the piezoelectric element 2o may strongly collide with the flat portion of the holding terminal plate 3o, and there is a risk that the corner portion may be damaged or otherwise damaged. However, it had the disadvantage of poor impact resistance.

On the other hand, in order to prevent damage to the corner portion of the piezoelectric element 2o, as shown in FIG. 8, a receiving protrusion 5o is formed around the holding protrusion 4o to receive the corner portion of the piezoelectric element 2o. A holding terminal plate 31o has been proposed, and a holding terminal plate 32o in which a damper 6o is attached to the periphery of the main plate portion as shown in FIG. 9 has been proposed.

However, as mentioned above, the receiving protrusion 5o
In the holding terminal plate 31o in which the holding protrusion 5o is formed, it is necessary to match the position of the receiving protrusion 5o to the size of the piezoelectric element 2o, and it is necessary to prepare many types of terminal plates with different positions of the receiving protrusion 2o.
Further, in the holding terminal plate 32o to which the damper 6o is attached, the process of attaching the damper is added in addition to the press working of the terminal plate itself, increasing the number of man-hours, and both have the disadvantage of being inferior in mass productivity.

The present invention was devised in view of the above-mentioned problems, and it effectively prevents damage such as breakage of the corners of the piezoelectric element, improves impact resistance, and has excellent mass productivity and can be manufactured at low cost. The purpose is to make it possible to

<Means for Solving the Problems> In order to achieve the above-mentioned purpose, the present invention abuts the vibration nodes of a piezoelectric element that has a larger external shape than the piezoelectric element and is housed in a case. A structure of a holding terminal plate for a piezoelectric element consisting of a main plate portion on which a protruding flat portion for holding is formed and a lead portion extending from the main plate portion, wherein an inclined surface portion is provided around the protruding flat portion, The inclined surface portion is characterized in that it is formed along a widening inclined surface that continuously connects the peripheral edges of the protruding plane portion and the main plate portion in a linear or curved shape in cross-sectional view.

<Example> Hereinafter, the present invention will be described in detail based on an example shown in the drawings. FIG. 1 is a cross-sectional view of a piezoelectric resonator having a holding terminal plate according to the present invention. In the case 1, the piezoelectric element 2 is held in pressure contact with the inner wall of the case 1 at the vibration node point of its vibration mode from both sides by both terminal plates 3, 3. . Each holding terminal plate 3
As shown in the perspective view of FIG. 2, the main plate part 3a has a structure in which a main plate part 3a having a larger external shape than the piezoelectric element 2 and a lead part 3b extending from the main plate part 3a are integrated. A protruding flat portion 4 is formed approximately in the center of the main plate portion 3a to abut against and hold the vibration node of the piezoelectric element 2 housed in the case 1, and is protruded from the periphery of the main plate portion 3a. and,
As shown in FIGS. 1 and 2, the main plate portion 3a has a widening inclined surface that continuously connects the peripheral edge of the protruding plane portion 4 and the peripheral edge of the main plate portion 3a in a straight line in cross-sectional view. An inclined surface portion 5 is formed along the slope of the cone and is a so-called truncated conical slope.

Therefore, when an external impact is applied to the piezoelectric resonator, the piezoelectric element 2 tilts significantly relative to the holding terminal plate 3, as shown in FIG.
The portion of the piezoelectric element 2 other than the vibration node point is received by the inclined surface portion 5, and the piezoelectric element 2 and the inclined surface portion 5 are in line contact, so that a local impact is not applied to the corner portion of the piezoelectric element 2. Therefore, the corner portion of the piezoelectric element 2 will not be damaged.

The reason why the outer shape of the main plate part 3a constituting the holding terminal plate 3a is made larger than that of the piezoelectric element 2 is that the corner part of the piezoelectric element 2 protrudes from the periphery of the main plate part 3a when tilted, and the case This is to prevent damage caused by direct collision with the inner wall of 1. Incidentally, the inclined surface portion 5 does not necessarily have to be formed over the entire surface of the main plate portion 3a, but may be formed at least around the protruding flat portion 4. That is,
FIG. 4 is a half-sectional view of another embodiment, and in the holding terminal plate 31 of this embodiment, the peripheral edges of the protruding plane portion 41 and the main plate portion 31a are connected continuously in a straight or curved shape in cross-sectional view. An inclined surface portion 51 formed along a widening inclined surface is provided only at a constant radius portion centered on the protruding plane portion 41. Note that at this time, it goes without saying that the length of the slope of the slope portion 51 is set to be at least half the length of the piezoelectric element 2 from the vibration node point to its periphery. This holding terminal plate 31 also provides the same effects as the embodiments shown in FIGS. 1 to 3.

Further, the cross-sectional shape of the inclined surface portion is not limited to a linear shape, and may be, for example, a curved shape that continues the peripheral edges of the protruding plane portion and the main plate portion. That is, FIG. 5 shows an embodiment in which a sloped surface portion having a curved shape in cross section is provided around the protruding flat surface portion, and the main plate portion 32 of the holding terminal plate 32
The protruding plane portion 42a and the inclined surface portion 52a at a
Both are bulged into a spherical shape with a widened base. In this embodiment, as the piezoelectric element 2 is tilted, the piezoelectric element 2 is sequentially received at different parts of the inclined surface part 52, so that no impact is locally applied to the corner part of the piezoelectric element 2, and the corner No damage to the parts will occur.

<Effects of the invention> As described above, according to the invention, when the piezoelectric element is tilted significantly with respect to the holding terminal plate due to an external impact, the portion of the piezoelectric element other than the vibration node point is received by the inclined surface portion. Therefore, the corner portion of the piezoelectric element does not collide with the holding terminal plate, and damage to the corner portion can be reliably prevented and impact resistance is improved.

Moreover, even if the size of the piezoelectric element is different, the damage prevention effect described above occurs, so there is no need to manufacture several types of piezoelectric elements depending on the size.
It is possible to produce large quantities of a single shape,
In addition, in manufacturing, the same pressing process as the conventional holding terminal plate is required and manufacturing is easy, so it is excellent in mass production and can be manufactured at low cost.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a piezoelectric resonator equipped with the holding terminal plate of the present invention, Fig. 2 is a perspective view of the holding terminal plate, Fig. 3 is an explanatory view showing the action of the holding terminal plate, and Fig. 4 is an illustration of other parts. FIG. 5 is a half-cut sectional view of another embodiment, FIG. 6 is a sectional view of a piezoelectric resonator equipped with a conventional holding terminal plate, and FIGS. 7 to 9 are sectional views of a conventional piezoelectric resonator. FIG. 3 is a plan view of the holding terminal board of FIG. 2... Piezoelectric element, 3, 31, 32... Holding terminal plate, 3a, 31a, 32a... Main plate portion, 4, 4
1, 42... Holding protrusion, 5, 51, 52... Inclined surface part.

Claims (1)

[Scope of Claim for Utility Model Registration] A main plate portion having a larger external shape than the piezoelectric element and on which a protruding plane portion is formed that abuts and holds the vibration node points of the piezoelectric element housed in the case, and a main plate portion extending from the main plate portion. A structure of a holding terminal plate for a piezoelectric element consisting of an extended lead portion, wherein an inclined surface portion is provided around the protruding flat portion, and the inclined surface portion is arranged between the peripheral edges of the protruding flat portion and the main plate portion. 1. A structure of a holding terminal plate for a piezoelectric element, characterized in that it is formed along a sloped surface with a flared base that connects continuously in a straight line or curved shape when viewed in cross section.