JPH0345162Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a piezoelectric shiatsu gauge used to measure the internal cylinder pressure of an engine, that is, the shiatsu chart. The present invention relates to a piezoelectric acupressure meter that can be assembled by increasing the drying effect of the piezoelectric element.

[Prior art]

An example of a conventional piezoelectric acupressure meter is shown and explained in Fig. 1. In the figure, numeral 1 is a cylindrical sleeve made of metal such as stainless steel as a case, and the inner circumferential surface of the bottom part 1a has the same shape. A plate-shaped pressure receiving part 2 made of a material is attached. Further, a cylindrical insulating member 3 made of Teflon or the like is inserted into the inner peripheral surface of the sleeve 1, and a pressure receiving portion 2 inside the insulating member 3 is inserted.
Plate-shaped piezoelectric elements 4a to 4e made of X-axis cut crystal are stacked and arranged on the upper surface of the device. In this case, a predetermined gap 5 is provided between the insulating member 3 and the piezoelectric elements 4a to 4e, and each piezoelectric element 4a to 4e is free of charge generated when pressurized in the X-axis direction. The electrodes are connected to each other so that their charges are added according to their polarities.

Further, an acceleration correction weight (also referred to as a mass) 6 made of tungsten and serving as an electrode is placed on the top surface of the piezoelectric elements 4a to 4e, and an acceleration correction weight 6 made of a perforated crystal with an X-axis cut is placed on the top surface of the weight 6. A correction piezoelectric element 7 is mounted. Furthermore, a bushing member 8 made of stainless steel and having a through hole 9 is disposed in close contact with the upper surface of the piezoelectric element 7.
The upper opening 1 of the case 1 is opened by the bushing member 8.
b is occluded. The lead wire 10 connected to the center of the upper surface of the acceleration correction weight 6 passes through the through hole 7a of the acceleration correction piezoelectric element 7 and is connected to a terminal 11 at a predetermined position in the through hole 9, and is pulled out to the outside. The terminal 11
is sealed by a sealing member 12 to hermetically seal the through hole 9 of the bushing member 8.

Note that the acceleration correction piezoelectric element 7 and the laminated piezoelectric elements 4a to 4e are connected to each other through an acceleration correction weight 6, so that the electrodes of each piezoelectric element 7 and the laminated piezoelectric elements 4a to 4e are mutually connected to each other through an acceleration correction weight 6 so as to cancel the electric charges generated by inertial force due to acceleration. The output is taken out between the case 1 and the terminal 11 from which the lead wire 10 of the acceleration correction weight 6 is drawn out.

By the way, in the piezoelectric acupressure meter having such a configuration, the electric charge generated from each of the piezoelectric elements 4a to 4e and 7 is extremely small, and in order to reduce the leakage and prevent deterioration of the piezoelectric elements, the electric charge is usually left in the sleeve 1. Methods of assembling in an environment with little moisture are being used. However, when drying the moisture inside the sleeve 1, as shown in FIG. There were problems such as the drying process taking a long time and insufficient drying, resulting in deterioration of the piezoelectric element.

[Summary of the idea]

This invention was made in view of the above points,
A ventilation groove is provided on the bottom surface of the bushing member that closes the top opening of the case in which the piezoelectric element is housed, communicating with a through hole made through the bottom surface, so that the inside of the case can be ventilated during the drying process. The present invention provides a piezoelectric acupressure meter that can enhance the drying effect of the piezoelectric element and improve its reliability by improving the properties of the piezoelectric element, and can also reduce costs. Hereinafter, embodiments of the present invention will be described with reference to the drawings.

〔Example〕

2 and 3 are a cross-sectional view and a perspective view of a bushing member, respectively, showing a schematic structure of a piezoelectric acupressure meter according to an embodiment of the present invention. In the acupressure meter of this embodiment, piezoelectric elements 4a to 4e, an acceleration correction weight 6, and an acceleration correction piezoelectric element 7 are sequentially laminated on the upper surface of a pressure receiving part 2 attached to a sleeve 1, and these are housed in the sleeve 1. Then, the upper opening 1b of the sleeve 1 is closed with a bushing member 8, the lead wire 10 connected to the acceleration correction weight 6 is pulled out through the through hole 9 of the bushing member 8, and the through hole 9 is hermetically sealed. The structure is similar to that of the conventional one shown in FIG. A cross-shaped ventilation groove 20 is provided on the bottom surface 8a of the bushing member 8 so as to communicate with the gap 5 between the insulating member 3 and the insulating member 3.

In this way, by providing the ventilation groove 20 in communication with the through hole 9 on the bottom surface of the bushing member 8 that closes the upper surface opening 1b of the sleeve 1, the bushing member In the drying process before sealing the through holes 9 of 8 with the sealing member 12, the moisture inside the sleeve 1 can be released through the ventilation grooves 20 and the through holes 9, so that the air permeability is significantly improved and the drying process is completed. This can be significantly reduced. Therefore, there is no need to assemble in a special environment with little moisture, and the moisture inside the sleeve 1 is removed by hermetically sealing the through hole 9 of the bushing member 8 in the same manner as before after a short drying process. Thus, the drying effect of each piezoelectric element 4a to 4e and 7 can be enhanced.

In addition, although the above-mentioned embodiment shows the case of a piezoelectric acupressure meter equipped with an acceleration correction mechanism, the present invention is not limited to this. Needless to say, the present invention can be similarly applied to a general piezoelectric type acupressure gauge having a structure in which the section is closed with a bushing member.

[Effect of idea]

As explained above, according to the piezoelectric acupressure meter of the present invention, the bottom surface of the bushing member that closes the top opening of the case in which the piezoelectric elements are stacked communicates with the through hole formed through the bottom surface. By providing ventilation grooves, the air permeability inside the case during the drying process is improved, and this process can be largely omitted, leading to a reduction in manufacturing costs. Moreover, since the piezoelectric elements inside the case can be sufficiently dried, leakage between the elements is reduced, deterioration of the elements can be prevented, and reliability can be improved.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a schematic structure of a piezoelectric shiatsu gauge according to a conventional example, and FIGS. 2 and 3 are sectional views showing a schematic structure of a piezoelectric shiatsu gauge according to an embodiment of the present invention, and a perspective view of a bushing member. It is a diagram. DESCRIPTION OF SYMBOLS 1... Sleeve, 2... Pressure receiving part, 3... Insulating member, 4a-4e... Piezoelectric element, 5... Gap part, 6
... Weight for acceleration correction, 7 ... Piezoelectric element for acceleration correction, 8 ... Bush member, 9 ... Through hole of bush member, 10 ... Lead wire, 11 ... Terminal, 12 ... Seal member, 20 ... ...ventilation groove.

Claims (1)

[Scope of utility model registration request] A piezoelectric element for converting the pressure into an electric signal is laminated on the upper surface of the pressure receiving part attached to the case, and these piezoelectric elements are housed in the case, and the upper surface opening of the case is formed by a bushing member having a through hole. In the piezoelectric acupressure gauge, the piezoelectric acupressure meter is configured to be closed and to draw out a lead wire connected to an electrode of the piezoelectric element through the through hole, and to hermetically seal the through hole. A piezoelectric acupressure gauge, characterized in that a ventilation groove is provided so that the through hole communicates with a gap between the piezoelectric elements laminated in the case and the case.