JPS6012340Y2 - piezoelectric tuning fork - Google Patents

Description

[Detailed Description of the Invention] The object of the present invention is to significantly reduce noise output due to external shocks and vibrations in a piezoelectric tuning fork having a structure in which a tuning fork is directly fixed to a ground terminal embedded in a terminal board.

Hereinafter, a conventional piezoelectric tuning fork will be shown together with FIG.

Reference numeral 1 denotes a tuning fork made of metal, which is bonded to piezoelectric ceramics 3, 3' near the vibration nodes of vibrating pieces 2, 2'.

Further, a ground terminal 5 is fixed to the connecting portion 4 of the vibrating pieces 2, 2' by welding or the like, and this ground terminal 5 is implanted in a terminal plate 6.

Input and output terminals 7, 8 are embedded in the terminal plate 6, and the output terminals 7, 8 are connected to the piezoelectric ceramics 3, 3' by lead wires 9, 10.

Conventionally, the tuning fork 1 was fixed directly to the ground terminal 5 as shown in FIG. 5, the tuning fork 1 is excited, which causes a noise output and causes malfunction of the circuit.

In order to prevent this inconvenience, a structure has been proposed in which the terminal plate and the tuning fork support are attached via a cushioning material such as rubber, and the ground terminal and the tuning fork support are connected by a thin lead wire.

However, this structure has the disadvantage that it is difficult to mass produce and is expensive due to its complicated structure.

The object of the present invention is to eliminate the above-mentioned disadvantages, to obtain a piezoelectric tuning fork that has a simple structure, is easy to mass-produce, and has low noise output due to external shocks and vibrations.

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3.

The configurations 1 to 10 shown in FIG. 2 are similar to the conventional example, but a vibration absorber 11 is further inserted and fixed to the tuning fork support portion of the ground terminal 5.

If this vibration absorber 11 is made of a so-called viscoelastic material such as butyl rubber, the noise output of the piezoelectric tuning fork can be minimized, but it may also be made of chloroprene rubber, silicone rubber, etc. depending on the desired degree of vibration suppression. good.

The vibration absorber 11 has a hole 12 in the center corresponding to the diameter of the ground terminal 5 in advance as shown in FIG. After the vibration absorber 11 is inserted into the earth terminal 5, the tuning fork 1 is fixed to the earth terminal 5 by welding or the like, and the vibration absorber 11, the earth terminal 5, and the terminal plate 6 are bonded together. The vibration absorber 11 is adhesively fixed with a rubber-like adhesive similar to that of the vibration absorber 11.

FIG. 4A shows a vibration absorber 11 in another embodiment of the present invention.
', a piece of the thick part has been cut, and the cut part 13
the vibration absorber 11' from the side of the ground terminal 5 using
It is configured so that it can be inserted.

Furthermore, the opening in FIG. 4 also shows a vibration absorber 11" according to another embodiment of the present invention, in which the diameter of the hole 12 is slightly larger than that of the ground terminal 5, and the hole 12 is connected to the upper part of the vibration absorber 11". An upper hole 14 with a larger diameter is provided, and after inserting into the ground terminal 5, by injecting a small amount of low-viscosity adhesive or the like into the upper hole 14, the vibration absorber 11''
can be easily adhesively fixed to the ground terminal 5 and the terminal plate 6.

The effects of the present invention are as follows.

(1) Since a vibration absorber is attached around the ground terminal, vibrations and shocks applied from the outside to the terminal board, case, terminals, etc. are absorbed by the vibration absorber.

That is, vibration of the ground terminal is suppressed.

Therefore, the degree to which the tuning fork is excited becomes extremely small, and almost no noise output that causes the circuit to malfunction is generated.

(2) Since the vibration absorber is pre-formed in a certain shape, the effect of absorbing vibration is stable at a certain level.
The effect of vibration absorption does not vary from product to product.

(3) Since a pre-formed vibration absorber is inserted and fixed into the ground terminal, handling is easier and mass production is easier than applying adhesive material.

In addition, manufacturing is much simpler, more mass-producible, and less expensive than the case where a buffer is inserted between the tuning fork support and the terminal plate to fix them to each other, and the tuning fork support and the ground terminal are connected by a lead wire.

(4) Even if the earth terminal has a relatively long and thin shape, the surrounding area can be supported with a certain wall thickness, so the mechanical strength of the supporting part is strong and it will not break even if large shocks or large vibrations are applied for a long time. No worries.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a conventional piezoelectric tuning fork, FIG. 2 is a perspective view of an embodiment of the piezoelectric tuning fork according to the present invention, and FIG. 3 is a perspective view of a vibration absorber constituting the piezoelectric tuning fork. Figure 4 A9
The mouth is a perspective view showing other embodiments of the vibration absorber. 1...Tuning fork, 5...Ground terminal, 6.
...Terminal board, 11. 11', 11"-...
... Vibration absorber, 12 ... Hole, 13 ...
...Cut section, 14...Top hole.

Claims (3)

[Scope of utility model registration request] (1) Insert a vibration absorbing material made of butyl rubber or the like, previously formed into a certain shape, into the ground terminal extended above the terminal board, fix this vibration absorbing material to the ground terminal and the terminal board, and A piezoelectric tuning fork with a tuning fork fixed to the tip by welding, etc. (2) A piezoelectric tuning fork according to claim (1), which uses a vibration absorber having a cut portion on one side of the thick portion. (3) A piezoelectric tuning fork according to claim 1, which uses a vibration absorber having a hole in the center with a diameter slightly larger than the diameter of the support and an upper hole with a diameter larger than the hole in the upper part.