JPH0342348Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a piezoelectric shiatsu gauge for measuring the internal cylinder pressure of an engine.

Conventional technology There are mechanical, pressure balanced, and electric types of shiatsu gauges that measure the pressure inside a cylinder. Among these, piezoelectric shiatsu gauges are small and have excellent sensitivity and responsiveness. Widely used.

For example, as shown in FIG. 2, a piezoelectric element 2, an electrode 3, and an insulating material 4 are inserted into a bottomed cylindrical sleeve 1, and an opening 1a of the sleeve 1 is fitted onto the cylindrical outer periphery 5a of a converter 5. The proximal end 6a of the case 6 and the seat portion 5b of the converting portion 5 are fixed by welding or the like while pressing the outer bottom surface 1b of the sleeve 1 into contact with each other. A lead wire 7 is connected to the electrode 3, and the lead wire 7 is led out through an insertion hole 5c formed in the center of the conversion section 5.

Problems to be Solved by the Invention However, in the conventional piezoelectric acupressure meter, the converting part 5 and the case 6 are fixed and have an integral structure, so it is not possible to disassemble them and take out only the converting part 5. However, there were problems in that the pressure-electrical characteristics of the converting section 5 could not be inspected until after the shiatsu gauge had been assembled, and that even if the shiatsu gauge broke down, it could not be repaired.

The present invention was made to solve these problems, and the purpose is to provide a piezoelectric shiatsumeter that allows the pressure-electrical characteristics of the converter to be inspected before assembling the shiatsumeter. .

Means for Solving the Problems The piezoelectric acupressure meter according to the present invention has an opening of a bottomed cylindrical metal sleeve that houses a piezoelectric element and an electrode inside, and a cylindrical shape having a threaded part on a part of the outer surface. A converting part assembly is constructed by welding and fixing to the tip of a shaped inner case, and a lead wire is taken out from the electrode inside the sleeve to the outside through an insertion hole inside the inner case, and a lead wire is taken out from the electrode inside the sleeve to the outside. A diaphragm is formed at the distal end of a hollow outer case that houses the assembly, an opening through which the converter assembly can pass is formed on the proximal end side, and heat insulation is provided between the inner surface of the diaphragm and the distal end of the sleeve. By inserting the conversion part assembly into the opening of the outer case with the material in between, and screwing together the threaded part formed on a partial inner surface of the opening and the threaded part of the inner case, It is constructed by pressing a sleeve against the diaphragm.

Function In the piezoelectric acupressure meter of the present invention, the conversion section, which consists of a sleeve that accommodates the piezoelectric element, an inner case, etc. that is fixed to the opening of the sleeve by welding, is assembled separately from the outer case, and the conversion section is assembled separately from the outer case. After assembling the sleeve and performing the necessary inspections, the sleeve is inserted into the opening of the outer case and the threaded part is screwed together. Since the converter is pressurized, it is not only easy to assemble, but also makes it possible to check whether there are any abnormalities in the pressure-electrical characteristics of the converter before assembling it to the outer case. can.

In addition, in the piezoelectric shiatsumeter of the present invention, the converter and outer case, which are a single assembly, are constructed so that they can be separated by a threaded part, so even after the converter is assembled to the outer case, Alternatively, even if the finished piezoelectric shiatsumeter is installed in the target engine, if an abnormality occurs in the converter, the converter can be removed from the outer case as an integrated assembly by unscrewing the inner case. Since it can be removed, it is convenient to replace it with a new one, repair it at a suitable location outside where it is easy to work, and even inspect its operating condition outside.

Embodiment An embodiment of the present invention will be described based on the drawings. Figure 1 is. 1 shows an embodiment of a piezoelectric acupressure meter according to the present invention.

First, a piezoelectric element 13 and an electrode 14 are sequentially housed inside a metal sleeve 16 having a cylindrical shape with a bottom, and a cylindrical outer periphery 17a at the tip of a cylindrical inner case 17 is placed in an opening 16a of the sleeve 16. The converter assembly is manufactured by inserting and fixing by spot welding or the like. and,
The converting portion is inserted into the outer case 12 fixed to the holder 11 through an opening thereof. At this time, the lead wire 18 is attached to the electrode 14.
One end 18a is connected, and this lead wire 18 is inserted into the insertion hole 17 formed in the center of the inner case 17.
The other end 18b is taken out to the outside through b.

A protrusion 16 is provided at the center of the outer bottom surface of the sleeve 16.
b is formed, and one end 19a of a cylindrical heat insulating material 19 made of ceramic or the like is in contact with the circumferential bottom surface 16c formed around this protrusion 16b, and the other end 19b is in contact with the inner surface 20a of the diaphragm 20. . The diaphragm 20 is formed integrally with the metal outer case 12 in this case, and has an annular groove 20b on its outer periphery for absorbing deformation due to thermal expansion.
is formed. Inner case 17 housed inside outer case 12 is supported by its guide portion 17c and fixed to outer case 12 by threaded portion 17d.

When assembling this shiatsu gauge, the inner case 17 is fixed in advance, and the opening 16a of the sleeve 16 is connected to the cylindrical outer periphery of the inner case 17.
When the piezoelectric element 13 is fitted into the sleeve 16 and fixed by spot welding or the like, a predetermined pressure (preload) is applied to the piezoelectric element 13 housed in the sleeve 16. Before the acupressure meter is assembled, it is possible to check the pressure-electrical characteristics of the converting section composed of the piezoelectric element 13, electrode 14, insulating material 15, inner case 17, sleeve 16, etc. In other words, it is possible to discover defects such as product defects in the piezoelectric element 13 and the like with these converters separated from the outer case 12, and if such defects are discovered, they can be easily repaired by replacing parts, etc. can be done. If the pressure-electrical characteristics are confirmed to be normal,
The conversion section and the heat insulating material 19 are combined and housed inside the outer case 12. At this time,
While one end 19b of the heat insulating material 19 is in contact with the inner surface 20a of the diaphragm 20, the inner case 17 is supported by the outer case 12 via the sleeve 16 by its guide portion 17c, and the threaded portion 1
These conversion parts are coupled to the inner periphery of the outer case 12 by 7d. During the screw connection, the screw is turned until the outer surface 20c of the diaphragm 20 undergoes a predetermined deformation amount 8. This prevents the outer case 12 and the heat insulating material 1 from occurring due to a difference in thermal expansion due to the temperature difference between the outer case 12 and the conversion section.
The settings are made so that no gap occurs between the two. In this case, since the amount of deformation 8 is adjusted by screw connection, adjustment work at the time of fastening can be easily performed.

The piezoelectric acupressure meter with the above configuration can be used for various pressure measurements, but if an abnormality occurs during the measurement, the converter etc. can be removed as a whole from the outer case 12 and the assembly procedure described above can be performed. It can be easily repaired by disassembling it in the reverse order.

Effects of the invention According to the invention, before completing the assembly of the piezoelectric shiatsumeter, the converting section consisting of the piezoelectric element, electrodes, sleeve, inner case, etc. is separated from the outer case as one assembly, and the pressure is applied only to the converting section. - Since the electrical characteristics can be inspected, it is possible to improve the quality of the product after the shiatsu gauge has been assembled, and to disassemble the shiatsu gauge if an abnormality occurs in the pressure-electrical characteristics during use. This makes it easy to investigate the cause of the abnormality and repair it. Further, according to the present invention, even after the shiatsu gauge has been assembled, the conversion section of the shiatsu gauge can be easily removed as an integral assembly, thereby making it easy to readjust and reassemble the shiatsu gauge.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view showing one embodiment of the present invention, and FIG. 2 is a partial sectional view showing a conventional example. 12...Outer case, 13...Piezoelectric element,
14... Electrode, 15... Insulating material, 16... Sleeve, 16a... Opening, 17... Inner case, 17a... Cylindrical outer periphery, 17c... Guide portion,
17d...screw part, 18...lead wire, 19...
Insulation material, 20... diaphragm.

Claims (1)

[Scope of utility model registration request] The converter assembly is assembled by welding and fixing the opening of a bottomed cylindrical metal sleeve that houses the piezoelectric element and electrodes to the tip of a cylindrical inner case that has a threaded part on a part of its outer surface. a diaphragm at the tip of a hollow outer case that houses the converter assembly;
An opening through which the converter assembly can pass is formed on the proximal end side, and a heat insulating material is sandwiched between the inner surface of the diaphragm and the distal end of the sleeve, and the converter assembly is inserted into the opening of the outer case. A piezoelectric acupressure gauge, characterized in that the sleeve is pressed against the diaphragm by inserting the sleeve into the diaphragm and screwing together a threaded part formed on a part of the inner surface of the opening and the threaded part of the inner case.