JPS5848605Y2 - Waterproof structure of pressure detection oscillator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a waterproof structure for a pressure detection oscillator suitable for use in automobiles.

Pressure detection in automobiles is often carried out to detect, for example, the pressure of engine oil or the vacuum pressure of a brake booster, and to display the suitability of the detection to the driver.

A pressure detection oscillator for detecting these pressure fluctuations and obtaining a displacement signal is generally equipped with a diaphragm.

Oscillators using this diaphragm combine the detected pressure with atmospheric pressure and a spring (some diaphragms have a spring force themselves).

), so the pressure in the chamber above the diaphragm must always be the same as atmospheric pressure.

By the way, as a pressure detection oscillator used in automobiles, the ambient temperature range is wide, so in order to make the upper chamber of the diaphragm have the same pressure as the atmospheric pressure, a vent hole must be provided to allow ventilation with the outside. I have to keep it.

However, since cars are driven and washed even in rainy weather, it is necessary to prevent water from entering through the ventilation holes.

In other words, it is required to have a structure that is contradictory to that of having ventilation but also requiring waterproofing.

However, in the past, when trying to create a structure that was both ventilated and waterproof as described above, the structure became complicated and large, and the pressure inside the oscillator case changed due to temperature changes, causing the diaphragm to Since it was unavoidable that the balance of power at the center would be thrown out of whack, ventilation was sometimes shut off to make it waterproof.

There are also devices that perform the necessary ventilation through adjustment threads, but this is because when the detected pressure changes from high pressure to low pressure, the inside of the oscillator chamber becomes negative pressure.
Atmospheric air is sucked in through the threads, and if there are water droplets in the air at this time, there is a risk that the water droplets will be sucked into the oscillator as well.

The present invention has been devised in view of the above-mentioned circumstances, and has been devised for the purpose of providing a waterproof structure for a pressure detection oscillator that achieves both ventilation and waterproof effects with a simple configuration.

An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view of a main part of a pressure detection oscillator showing a waterproof structure according to the present invention, and FIG. 2 is an exploded perspective view thereof.

Reference numeral 1 denotes a case of a main body of a pressure detection oscillator, in which a pressure detection mechanism and the like are provided, but the details thereof are not directly related to the explanation of the present invention, so illustrations and explanations thereof are omitted.

A hole 11 is formed in the upper surface of the case 1, and a housing 3 made of plastic, for example, is placed so as to cover the hole 1.

The housing 3 has a U-shaped cross section, has a notch 31 on its upper surface, a through hole 32 in the center of the notch 31, and has an appropriate number of grooves 33 formed at its lower end to communicate the inner and outer walls.

An elastic backing 4 is housed inside the housing 3.

The backing 4 has a hollow cylindrical shape, and has concave and convex grooves 41 and 42 formed on its outer and inner surfaces, and has inner and outer grooves on its upper surface.
A groove 43 is formed to communicate the outer surfaces, and a step 44 is further formed at the lower part.

This stepped portion 44 is engaged with the hole 11 of the case 1.

A terminal 5 for deriving an output signal is placed in the notch 31 of the housing 3, and a rivet 6 is inserted through the through hole 51.

The lower end of the rivet 6 protrudes into the case 1 through the hollow part of the backing 4, and the insulating seat 7. It is tightened with washer 8.

Note that recesses 72.82 are formed in the holes 71.81 of the insulating washer 7 and the washer 8, respectively.

The present invention is constructed as described above, and the ventilation inside and outside of the case 1 is controlled by: the groove 33 on the lower end of the housing 3 - the groove 41 on the outer surface of the backing - the groove 43 on the top surface of the backing - the groove 43 on the inner surface of the backing 42 - recess 72 of the insulating washer - recess 82 of the washer, and the inside of the case 1, that is, the chamber above the diaphragm (not shown) can be maintained at the same pressure as atmospheric pressure.

In addition, the outer surface and inner surface of the backing 4 have ridge-like irregularities 41.
42, the route is long and the route is folded up and down, so a sufficient waterproof effect can be obtained.

As mentioned above, the present invention allows for a long ventilation path, provides a sufficient waterproof effect, and has a structure in which the ventilation path is folded up and down. It can be configured with a small size, making it possible to make it smaller.

Furthermore, since the backing is an elastic material, by using backings with different heights, it is possible to change the pitch of the concave and convex grooves on the outer and inner surfaces of the backing, making it possible to control the waterproofing effect in various ways. .

Note that the terminal 5 is electrically connected to the internal mechanism of the pressure detection oscillator shown in the case 1, and output signals related to pressure fluctuations are derived. It is connected to a lamp etc.

The case 1 and the terminal 5 are electrically insulated by the housing 3, the backing 4, and the insulating seat 7.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part showing an embodiment of the waterproof structure of a pressure detection oscillator according to the present invention, and FIG. 2 is an exploded perspective view of FIG. 1. 1... Pressure detection oscillator case, 3...
...Housing, 33.43...Groove, 4...
... Backing, 41.42 ... Thread-like unevenness.

Claims (1)

[Scope of utility model registration request] It consists of a pressure detection oscillator body, a housing that is fixed and placed so as to cover a hole formed in the case of this body and has a groove at its lower end that communicates the inside and outside, and a hollow elastic body that is housed within this housing. What is claimed is: 1. A waterproof structure for a pressure detection oscillator, comprising: a backing having thread-like irregularities on an outer surface and an inner surface, and a groove formed on an upper surface to communicate the outer surface and the inner surface.