JPS587701Y2 - Atsuden Rohaki - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a piezoelectric filter using a piezoelectric vibrator.

FIG. 1 shows a conventional piezoelectric filter.

1 is a piezoelectric vibrator of radial vibration, and electrodes 1a are provided on its upper and lower surfaces.

2 is a lead wire, one end of which is connected to the center 1b of the electrode 1a, and the other end connected to the connection terminal 3.

4 is an elastic material, 5 is a case, and 6 is its lid.

This piezoelectric filter includes a piezoelectric vibrator 1 with a lead wire 2 soldered to the center 1b of an electrode 1a, which is housed in an elastic material 4 processed to have approximately the same external shape as the piezoelectric vibrator 1, and a case. 5 and the lid 6.

Therefore, this piezoelectric filter has the following drawbacks.

(a) Since the case 5 and the lid 6 are required, the cost is high and the size is large.

(b) Furthermore, in order to accommodate the piezoelectric vibrator 1, the elastic material 4 must be processed to have approximately the same external shape as the piezoelectric vibrator 1, which increases the cost.

(C) Also, the elastic material 4 is selected from a material that does not support the influence of the piezoelectric vibrator 1 as much as possible, but it tends to cause variations in the contact pressure on the piezoelectric vibrator 1, and is resistant to external vibrations and shocks. Performance becomes unstable.

The present invention aims to eliminate these drawbacks by providing a small-sized piezoelectric filter with stable performance and low cost.

FIG. 2 shows an embodiment of the present invention.

1.2 and 3 are piezoelectric vibrators, lead wires, and connection terminals similar to those shown in FIG.

14 is an elastic material layer, 24 is a self-adhesive silicone rubber tape, and 15 is a synthetic resin layer.

Self-adhesive silicone rubber is silicone rubber that has the property of adhering to each other but not to other materials.

Now, in this piezoelectric filter, a piezoelectric vibrator 1 with a node wire 2 soldered to the center 1b of an electrode 1a is wrapped in self-bonding silicone rubber tape 24, and a self-bonding silicone rubber is wrapped around the outer periphery of the piezoelectric vibrator 1. A layer of rubber is formed, a liquid elastic material such as ordinary silicone rubber is applied to the outer periphery, and the organic solvent is evaporated to form an elastic material layer 14, and the outer periphery is coated with a synthetic resin such as epoxy resin. is coated and heated to form a synthetic resin layer 15.
was formed.

Note that the other end of the lead wire 2 is connected to the connection terminal 3 as in FIG.

For this reason, this piezoelectric filter is more effective than conventional piezoelectric filters (
b) Since the case 5 and lid 6 shown in FIG. 1 are not required, the cost is low and the size is small.

(b) Furthermore, since the elastic material layer 14 does not need to be processed, the cost is further reduced.

(c) Also, since the tapes 24 adhere to each other but do not directly touch the piezoelectric vibrator 1, the performance of the piezoelectric vibrator is not affected by external vibrations and shocks.

In this embodiment, the elastic material layer 1 is provided on the outer periphery of the tape 24.
4, however, this elastic material layer 14 may be omitted and the synthetic resin layer 15 may be provided directly on the outer periphery of the tape 24.

As described above, the present invention has a layer of self-adhesive silicone rubber on the outer periphery of a piezoelectric vibrator with lead wires connected to electrodes, and the outer periphery is made of a synthetic resin layer, so it has stable performance. This is a small, low-cost piezoelectric filter.

[Brief explanation of drawings]

FIG. 1 is a main sectional view of a conventional piezoelectric filter, and FIG. 2 is a main sectional view of a piezoelectric filter of the present invention. 1... Piezoelectric vibrator, 1a... Same electrode,
2...Lead wire, 4...Elastic material, 14
...Elastic material layer, 15...Synthetic resin layer,
24...Self-adhesive silicone rubber tape.

Claims (1)

[Scope of utility model registration request] A piezoelectric filter characterized in that a layer of self-adhesive silicone rubber is provided on the outer periphery of a piezoelectric vibrator having a lead wire connected to an electrode, and the outer periphery is formed of a synthetic resin layer.