JPS587086Y2 - Safety device to prevent fuel leakage in vehicles, etc. - Google Patents

Description

[Detailed description of the invention] The safety device of the present invention, in particular, prevents fuel from leaking to the outside when a diaphragm member, etc. that is disposed in a fuel supply passage of a vehicle or the like and forms the fuel supply passage is damaged. Regarding safety equipment.

Conventionally, in electronic fuel injection systems for vehicles, fuel pressure control valve devices have a diaphragm-type valve member that is exposed to the fuel passage and swings depending on the fuel pressure, or a fuel pressure control valve device that is exposed to the fuel passage and has a diaphragm type valve member that swings depending on the fuel pressure. Diaphragm type damper devices and the like that swing in response have been proposed.

However, in the above-mentioned type of diaphragm device, the diaphragm is damaged due to diaphragm fatigue, etc.
There were disadvantages such as fuel leaking and flowing out.

Therefore, the present invention aims to provide a new safety device that eliminates the above-mentioned disadvantages, thereby preventing fuel from leaking to the outside when the diaphragm or the like is damaged.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a damper device 10 for absorbing and preventing pulsations in fuel or fuel pressure, and the device 10 is installed, for example, in a fuel passage connecting a fuel pump (not shown) of an electronic fuel injection system and an injection port for fuel injection. will be placed.

The damper device 10 has a housing 13 in which a port 11 leading to a fuel pump and a port 12 leading to an injection are disposed, and a cover 14 is fixedly disposed on the housing 13.

A diaphragm member 15, which is sandwiched and held on the outer periphery by the housing 13 and the cover 14 and is protected by rubber or the like, is attached to the swinging member 1.
6, and an inner periphery which is held and held by a retainer 17 fixedly arranged on the member 16.

A chamber 18 forming a fuel passage and an atmospheric chamber 19 are defined within the housing 13 and the cover 14.

The diaphragm member 15 and the swinging member 16 are connected to the retainer 17
Normally, the spring 20 is urged to the illustrated position by a spring 20 whose one end is locked, and is brought into contact with the tip of the inwardly extending portion 21 of the housing 13 .

Even in this state, communication between the port 11 and the chamber 18, and therefore the port 12, is ensured through the passage 22 formed in the extension portion 21.

The other end of the spring 20 has an O-ring type seal 23, and a resin valve holding member 2 is fitted into the cover 14.
4 is locked.

A floating resin valve member 26 is disposed within the holding member 24 and is biased to the position shown in FIG. 1 by a further spring 25, one end of which is secured to the cover 14.

The valve member 26 has a T-shaped passage 27, and the atmospheric pressure chamber 19 normally communicates with the atmosphere through the passage 27, an air hole 28 formed in the cover 14, and a passage 29 formed in the holding member 24. are doing.

The valve member 26 has a valve portion 30 at its upper end, which comes into contact with the cover 14 to block the air hole 28 when the valve member 26 is displaced upward against the spring 25 as described later.

In the device of the present invention configured as described above, the pulsations in the supplied fuel and fuel pressure that occur during the discharge operation of the fuel pump, or the pulsations in the fuel and fuel pressure that occur during fuel injection via injection, and the back propagation of the pulsations. Abnormal noises generated by this are prevented from being absorbed by the diaphragm member 15 and the swinging member 16, which are displaced against the spring 20 in response to the pulsating pressure, and which make the effective volume of the fuel passage variable.

As a result, the diaphragm member 15 etc. were damaged, and the fuel leaked into the chamber 1.
8 to the atmospheric chamber 19, the fuel, which has a lower viscosity coefficient than air, causes the valve member 26 to resist the spring 25 and close to the air hole due to the increased flow resistance, especially through the passage 27 of the valve member 26. 28 is biased in the closing direction, and the valve member 26 is displaced upwardly as shown in FIG. 2 to block the air hole 28.

Therefore, the fuel leaked from the chamber 18 to the atmospheric chamber 19 does not leak to the outside.

FIG. 3 shows a modified embodiment in which a safety device comprising the above-mentioned valve member and the like is disposed in a fuel pressure control device 50 of an electronic fuel injection system.

However, the structure and operation of the safety device itself are substantially the same as those of the embodiments described above, and therefore are designated by the same reference numerals as those of the embodiments described above, and detailed explanation thereof will be omitted.

The fuel pressure control device 50 includes a housing 52 fixed with bolts or the like on a fuel delivery pipe 51 in which an injection is provided, and a cover 53 fixed to the housing 52.
has.

A diaphragm member 54, whose outer periphery is sandwiched between the housing 52 and the cover 53, has its inner periphery sandwiched and supported by a swinging member 55 and a plate 56 fitted into the member 55, thereby partitioning compartments 57 and 58. ing.

The chamber 57 is connected to the delivery pipe 51 so as to constantly receive fuel, and can be connected to an IJ-IJ-F pipe line 59 leading to a fuel tank via a valve mechanism to be described later.

A hollow tubular member 60 that acts as a seat is press-fitted into the housing 52, and when the swinging member 55 is in the illustrated position by a spring 61 stretched in the chamber 58, the seat 60 is pressed into the housing 52.
A floating valve 63 is disposed within the swinging member 55 and is biased by a spring 62 into contact with the floating valve 63 .

The swinging member 55 has a hollow extending portion 64 that comes into contact with the housing 52 and has a stopper function, and a bushing 65 made of an alloy with a low coefficient of friction such as Teflon, lead, bronze, etc. is provided on the inner wall of the extending portion 64. It is press-fitted.

The chamber 58 is connected to the intake manifold of the engine via a conduit 66, and constitutes a negative pressure chamber that receives negative pressure responsive to the opening degree of the throttle valve.

In the modified embodiment configured as described above, when the fuel pressure in the fuel supply passage, and therefore in the chamber 57, is below a predetermined value, the swinging member 55 is held at the illustrated position by the spring 61, and the valve 63 contacts the sheet 60 and blocks the chamber 57 from the relief conduit 59.

When the fuel pressure in the chamber 57 exceeds a predetermined value, the diaphragm member 54 and the swinging member 55 are displaced upward against the spring 61, and the bush 65 integrated with the swinging member 55 moves the valve 63 away from the seat 60. separated, chamber 57
It is connected to the IJ-F pipe line 59.

In this way, the fuel is relieved into the tank, and when the pressure drops below a predetermined pressure, the swinging member 55 is urged downward by the spring, and the valve 63 comes into contact with the seat 60.

Thereafter, by repeating the above action, the fuel pressure is controlled to a desired value and desired fuel injection becomes possible.

Note that during the fuel pressure control operation, the force that urges the swinging member 55 in the direction of opening the valve 63 changes due to fluctuations in the negative pressure of the intake manifold transmitted to the chamber 58, and thus the intake manifold negative pressure increases. Indeed, the fuel control pressure is made small, making it possible to perform optimal fuel pressure control in response to the driving condition of the vehicle.

If fuel leaks into the chamber 58 due to a defect in the diaphragm member 54 or the like, the valve member 26 moves to the illustrated position to cut off the conduit 66 from the chamber 58, as in the previous embodiment, so details will not be given. Further explanation will be omitted.

As detailed above, according to the device of the present invention, if the diaphragm member etc. that partition the fuel passage breaks and fuel leaks, the safety valve device operates by utilizing the relatively thick viscosity coefficient of the leaked fuel. Since this is provided, leaked fuel will not leak or flow out to the outside, and will not pollute the inside of the engine room, and will have the effect of preventing dangers such as ignition.

It is clear that the valve member constituting the safety device may be made of rubber, steel, or the like.

[Brief Description of the Drawings] Fig. 1 is a sectional view showing one embodiment of the device of the present invention, Fig. 2 is a sectional view showing the operating state of the main parts of Fig. 1, and Fig. 3 is a sectional view showing a modified embodiment. It is a figure similar to figure 1. DESCRIPTION OF SYMBOLS 10... Damper device, 13... Housing, 14... Cover, 15... Diaphragm member, 16... Rocking member, 18 ,1
9... Chamber, 20... Spring, 24
... Valve holding member, 25 ... Spring, 26 ... Valve member, 27 ...
Passage, 28... Air hole, 30... Valve section, 50... Fuel pressure control device, 52...
Housing, 53...Cover, 54...
・Diaphragm member, 55... Swinging member, 57
．． 58...Room.

Claims (1)

[Scope of utility model registration request] A first chamber through which fuel can be transmitted and a second chamber having an opening connected to the atmosphere or a signal pressure source are defined in a housing disposed in the fuel passage, and the fuel pressure in the first chamber is A diaphragm is provided which swings by a diaphragm, and a normally open valve device is provided in the second chamber, which is displaced to a position where the opening is blocked by fuel pressure leaking into the second chamber when the diaphragm or the like is damaged. A safety device to prevent fuel leakage.