JPS5922284Y2 - pressure switch circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a pressure switch that is mainly used and effective for detecting negative pressure.

Automobiles using easel engines are equipped with a pressure switch that lights up a warning lamp to warn when the air cleaner in the engine intake system becomes clogged.

This pressure switch is connected to the engine intake pipe.
It is just a pressure switch that closes when the intake pipe negative pressure exceeds a certain value due to air cleaner clogging, and current flows through the indicator lamp.If the indicator lamp goes out, you may not know about it. , it was inconvenient.

In view of the above, the purpose of this invention is to propose a pressure switch circuit that automatically checks for burnout of the lamp.

The embodiments shown in the drawings will be described below.

In Fig. 1, 1 is a diaphragm whose outer edges are airtightly bonded to a container body 2 and a cover 3.The center portion of the diaphragm is bonded to a shell 4 and a plate 5, and the upper surface of the plate 5 is covered with a U-shaped magnetic material. A frame 6 is attached with its open legs facing upward.

This frame 6 is made of a ferromagnetic material such as iron.

A spring 7 is disposed between the shell 4 and the cover 3 and always urges the diaphragm 1 and the magnetic frame 6 upward.

8 is a pressure chamber surrounded by a diaphragm 1 and a cover 3;
A rubber tube (not shown), one end of which is connected to the connecting tube portion 9 of the cover 3, is connected to the intake pipe of the engine.

Reference numeral 10 denotes a permanent magnet magnetized in the left-right direction in the figure, which is adhesively fixed to the inside of the upper part of the vessel body 2, and its magnetic pole portions at both left and right ends correspond to the distance between the leg opening ends 6a and 6b of the magnetic frame 6. Its position is determined so that it is located slightly inside.

Reference numeral 11 denotes a normally open reed switch provided on the outside of the upper part of the container body 2, and a coil 12 is wound around its outer periphery as shown in the figure.

These reed switch 11 and coil 12 constitute a so-called reed relay, which is molded with synthetic resin 13 and is fixed to the upper surface of body 2 as a whole.

The lead wires of the reed switch 11 and the coil 12 are connected to external connection terminals by suitable known means (not shown).

Figure 2 shows a pressure switch in which the reed relay is different from that shown in Figure 1, in which a normally open reed switch 11 is replaced by a synthetic resin 1
The coil 12 wound around the U-shaped iron core 14 is molded with synthetic resin 13'' and is superimposed and fixed on the reed switch 11. Both legs of the U-shaped core 14 are arranged close to the lead pull-out portion of the reed switch 11.

The pressure switches described above are connected as shown in FIG.

In the figure, 15 is an automobile key switch, which is a well-known A
It has M, ACC, IG, and ST contacts, the switching contact side of which is connected to one end of the battery 16, and the other end of the battery is grounded.

17 is a known oil pressure switch having a normally closed contact for detecting the pressure of lubricating oil in the engine, and 18 is an indicator lamp.

The reed relay 11 and the indicator lamp are connected in series, and one end is connected to the ignition terminal of the key switch 15, that is, I
It is connected to the G contact (IG), and the other end is grounded.

Further, the oil pressure switch 17 and the coil 12 are connected in series, and one end of this series circuit is connected to an IU contact (IG), and the other end is grounded.

In the above device, the key switch 15 and the IG contact (I
G), the coil 12 is turned on via the oil pressure switch 17.
A current flows through the reed switch 11 and the indicator lamp 1 is closed.
8 lights up, indicating that the lamp is not burnt out.

Next, put the key switch in the ST contact to start the engine, and then return it to the G contact position. As the pressure of the lubricating oil increases, the oil pressure switch 17 opens and the excitation current of the coil 12 is cut off, and the reed switch 11 is restored and indicator lamp 1
8 goes out.

When the air cleaner becomes clogged, the negative pressure in the intake pipe becomes abnormally large, which increases the negative pressure applied to the pressure chamber 8, causing the diaphragm 1 and the magnetic frame to move downward against the spring 7.
Since the air gap increases between the magnetic pole of the permanent magnet 10 and the magnetic frame 6, and the magnetic resistance increases, the lines of magnetic force from the permanent magnet 10 reach the reed switch 11, and the normally closed contact of the reed switch 11 is closed and the indicator lamp 18 lights up.

As mentioned above, according to this invention, inspection for indicator lamp burnout is automatically performed, and the reliability is high due to the use of a reed switch, and the operation of the reed switch itself can be checked at the same time as inspection for lamp burnout. There is.

[Brief explanation of drawings]

The drawings show embodiments of this invention, with FIGS. 1 and 2 showing cross sections of different embodiments of the pressure switch, and FIG. 3 showing the main parts of the electric circuit of the vehicle. 1...diaphragm, 2...vessel body, 6
...Magnetic frame, 6a, 6b...
Opening leg, 8...pressure chamber, 10...permanent magnet, 11...reed switch, 12...
...Coil, 15...Key switch 17...
...Oil pressure switch, 18...Indication lamp,
(IG)... IG contact.

Claims (1)

[Scope of utility model registration request] a diaphragm, a pressure chamber provided on one side of the diaphragm and connected to the intake pipe of the engine; a magnetic frame fixed to the diaphragm and having open legs; It has a permanent magnet disposed close to the opening leg, a normally open reed switch disposed close to the permanent magnet, and a coil for activating the reed switch. A diaphragm causes the opening leg of the magnetic frame to move away from the magnetic pole of the permanent magnet, and the magnetic field line of the permanent magnet has a pressure switch that operates the reed switch, and a normally closed contact for detecting the pressure of lubricating oil. An oil pressure switch and an indicator lamp are provided, and a series circuit is formed in which the reed switch and the indicator lamp are connected in series, and a series circuit is formed in which the oil pressure switch and the coil are connected in series, and one end of each of these plane series circuits is configured. A pressure switch circuit characterized in that the pressure switch circuit is connected to an IG contact of a vehicle key switch.