JPH048631A - Structure of fuel system of car - Google Patents

Abstract

PURPOSE:To widen the degree of freedom in the layout of a fuel system by shutting off fuel feed to the feed pipe side when a feed pipe or a return pipe is broken in the event of car collision, collecting the fuel staying backstream of the broken point to back to the tank, and thereby minimizing the outflow of the fuel to the outside. CONSTITUTION:When deceleration exceeds a certain specified value in the event of car collision, a deceleration sensor 10 senses it to actuate a solenoid valve 9, and the discharged fuel from a fuel pump 4 is switched from the supply device 6 side to the divergent pipe 7 side. Therefore, the discharge fuel is not sent to the supply device 6, but passes the divergent pipe 7 to come into a nozzle 12 of an ejector pump 11, wherefrom it is returned to the tank body 1. When a feed pipe 2 is broken at A-part in the event of collision, the discharged fuel from the pump 4 is led to the nozzle 12 and supplied as working fluid for the pump 11, so that a neg. pressure is generated in a chamber 13, into which the fuel staying backstream of A-part is sucked as the liquid to be worked. This is collected to the tank body 1 together with the jetting fuel from the nozzle 12.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a vehicle fuel system structure.

BACKGROUND ART FIG. 6 shows a general fuel system of a vehicle. Between a fuel supply device 6 attached to an engine 5 mounted at the front of the vehicle body and a tank body I mounted at the rear of the vehicle body, The fill vibe 2 and the return pipe 3 are communicated and connected, and the fuel sent out from the tank body l by the fuel pump 4 is supplied to the fuel supply device 6 through the feed pipe 2, and the fuel is supplied to the fuel supply device 6 by the fuel supply device 6. Surplus fuel that is not consumed is returned to the tank body I via a return pipe 3. This similar structure is shown in, for example, Japanese Unexamined Patent Publication No. 181914/1983.

Problems to be Solved by the Invention If the feed pipe 2 or the return pipe 3 breaks midway during a vehicle collision, fuel will flow out from the broken part, so these feed pipes 2. The layout of the return pipe 3 is severely restricted. Therefore, the present invention provides a feed vibe that can minimize the external outflow of fuel even if the feed pipe or return pipe is broken during a vehicle collision.

The present invention provides a fuel system structure for a vehicle that can expand the degree of freedom in the arrangement layout of the fuel system, including a return pipe.

Means for Solving the Problem A branch pipe is provided downstream of the fuel pump of the feed pipe that feeds the fuel in the tank body to the fuel supply device by the operation of the fuel pump, and a branch pipe is installed at the branch part of the branch pipe to detect the deceleration at the time of a vehicle collision. A flow path switching means is provided to detect the fuel pump and switch the delivery of the fuel discharged from the fuel pump from the fuel supply device side to the branch pipe side. The branch pipe communicates with the nozzle that spouts the working fluid, and the return pipe that returns excess fuel from the fuel supply device to the tank body communicates with the chamber that introduces the fluid to be operated of the ejector pump.

Under normal operating conditions, fuel discharged from the fuel pump is sent to the engine's fuel supply system through the foot pipe, and excess fuel that is not consumed by the fuel supply system passes through the return pipe to the ejector pump. is introduced into the chamber and returned into the tank body via the chamber. When a vehicle collides, the flow path switching means quickly senses the deceleration of the vehicle and immediately switches the flow path from the fuel supply device side to the branch pipe side. As a result, the fuel discharged from the fuel pump is introduced into the nozzle of the ejector pump through the branch pipe, and is ejected from the nozzle and returned into the tank body. Additionally, if either the feed vibe or the return pipe breaks during this collision, the fuel discharged from the fuel pump will be introduced into the nozzle of the ejector pump and used as the working fluid for the ejector pump, as described above. Therefore, the fuel downstream of the broken portion of the pipe is sucked into the chamber as actuated fluid, and is returned into the tank body together with the fuel jetted from the nozzle.

Example Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In FIGS. 1 to 3, I is a tank body, and a fuel pump 4 is disposed inside the tank body l. When the fuel pump 4 is driven, the fuel in the tank body 1 is filtered by a filter 4a. The fuel is then fed to the fuel supply bag R6 of the engine 5 via the feed vibe 2. Further, surplus fuel that is not consumed by the fuel supply device 6 is returned to the tank body l via the return pipe 3. These basic structures are the same as those of the prior art.

Here, the feed vibe 2 located downstream of the fuel pump 4 of the feed vibe 2, specifically within the tank body 1,
A branch pipe 7 is provided in the middle of the flow path, and a flow path switching means 8 is provided at this branch portion.

In this embodiment, the flow path switching means 8 includes a solenoid valve 9 disposed at the branch portion, and a deceleration sensor 10 that sends an activation signal to the solenoid valve 9 when the deceleration exceeds a predetermined value at the time of a vehicle collision. is used. The solenoid valve 9 has a valve body 9a that shuts off the branch pipe 7 and opens the feed vibe 2 in a normal state, and a valve body 9a that shuts off the branch pipe 7 and opens the feed vibe 2 in response to a signal from the deceleration sensor IO at the time of a collision.
The solenoid 9b pulls the feed vibration 2, cuts off the feed vibration 2, and opens the branch pipe 7.

That is, in this embodiment, when the deceleration sensor IO detects deceleration at the time of a vehicle collision, the solenoid valve 9 is immediately operated to switch the flow path from the fuel supply device 6 side to the branch pipe 7 side.

On the other hand, an ejector pump 11 is disposed within the tank body l. This ejector pump 11 has a chamber 13 in which a nozzle 12 for ejecting working fluid is installed.
A constriction part 14 and a throat part 15 are arranged in series below the nozzle 12, and when the working fluid is ejected from the nozzle 12 and negative pressure is generated in the chamber 13, the chamber 1
The actuated fluid is sucked and introduced into the throttle part 14. The liquid is discharged via the throat portion 15. The branch pipe 7 is communicated and connected to the nozzle I2 of the ejector pump 11, and the return pipe 3 is communicated to the chamber 13 of the ejector pump 11.
It is connected.

Next, the operation of the structure of the above embodiment will be explained.

Under normal conditions, fuel in the tank body 1 is fed to the fuel supply device 6 of the engine 5 through the feed pipe 2 by driving the fuel pump 4 . Surplus fuel that is not consumed by this fuel supply device 6 is introduced into the chamber 13 of the ejector pump 11 through the return pipe 3, and the constricted portion 14 of the chamber 13. It flows down the throat part 15 and returns into the tank body l.

When a vehicle collides and the deceleration of the vehicle exceeds a predetermined value, the deceleration sensor 1O detects this and promptly operates the solenoid valve 9 to transfer the fuel discharged from the fuel pump 4 from the fuel supply device 6 side to the branch pipe. Immediately switch the feed to the 7 side. As a result, the fuel discharged from the fuel pump 4 is not sent to the fuel supply device 6, but is introduced into the nozzle 12 of the ejector pump 11 through the branch vibe 7,
2 and returned into the tank body 1.

Furthermore, if either the foot pipe 2 or the return pipe 3 is broken during this collision, for example, if the feed vibe 2 is broken at part A in FIG. 1, the fuel discharged from the fuel pump 4 will be Since the fuel is introduced into the nozzle 12 of the ejector pump 11 and used as the working fluid of the ejector pump II, a negative pressure is generated in the chamber 13, and the fuel flowing downstream from the breakage point A is generated in the chamber 13. The fluid is sucked in as the actuated fluid, and the fuel is ejected from the nozzle 12 together with the throttle section 14 . It passes through the throat portion I5 and is collected into the tank body 1.

Here, especially as described above, when fuel is injected from the nozzle 12 and the ejector pump 11 is started at the time of a vehicle collision,
In the normal state before the collision, return fuel continues to be introduced into the chamber 13, and the constriction part I in the chamber 13
Since the fourth side is in a full state, the rise of negative pressure in the chamber 13 is accelerated, and the ejector pump II
Since the priming characteristics of the fuel cell are improved, the above-mentioned fuel recovery can be carried out efficiently.

FIG. 4.5 shows a different example of the flow path switching means 8.

An annular passage I6 is formed in the middle of the foot pipe 2 downstream of the fuel pump 4. This annular passage 16 communicates with the foot pipe 2 through a plurality of radial passages 17, for example, four, and the branch passage 7 is connected to this annular passage 16. A valve seat 1 is provided in each radiation passage I7.
8 and a hole check valve 19 are provided. In the normal state, the hole check valve 19 closes the valve seat 18 due to its own weight and blocks the annular passage 16, but when a predetermined deceleration occurs, the radial passage 17 is closed due to inertia.
It rolls over the fixed position regulating part 17a on the bottom and rolls into the feed vibe 2, and receives the discharge pressure of the fuel pump 4 and comes into close contact with the valve seat 20 at the downstream opening end of the feed vibe 2, causing the foot pipe 2 to It is designed to be blocked.

Therefore, in the case of this embodiment, the hole check valve 19 of any one of the radiation passages 17 will detect deceleration regardless of whether the vehicle is involved in a frontal/rearward collision or a side collision. When it rolls into the feed vibe 2, the hole check valve 19 immediately shuts off the foot pipe 2 and opens the annular passage 16.
Switch the flow path to the branch pipe 7 side.

In addition, in the above embodiment, the fuel pump 4 is connected to the tank body 1.
Although the case of a so-called in-tank pump type fuel tank in which the fuel pump is disposed inside the fuel tank has been disclosed, it is of course applicable to a fuel tank in which the fuel pump is disposed outside the tank body.

Effects of the Invention As described above, according to the present invention, even if either the feed pipe or the return pipe breaks during a vehicle collision, the fuel delivery to the feed pipe side is immediately cut off, and the fuel downstream from the breakage point is immediately cut off. Since the fuel can be collected inside the tank body, the leakage of fuel to the outside can be suppressed to the lowest possible level, further improving safety, as well as allowing freedom in the layout of the fuel system, including foot pipes and return pipes. It has a great practical effect of being able to expand the power.

[Brief explanation of drawings]

Fig. 1 is a system diagram showing embodiments of the present invention, Fig. 2 is a sectional view of an ejector pump, Figs. 3 and 4 are sectional views showing various examples of flow path switching means, and Fig. 5 is FIG. 4 is a schematic perspective view of the flow path switching means, and FIG. 6 is a system diagram showing a conventional fuel system. l...Tank body, 2...Feed pipe, 3...
・Return pipe, 4...Fuel pump, 6...
Fuel supply device, 7... Branch pipe, 8... Channel switching means, 11... Ejector pump, 12... Nozzle,
13...Chamber. 1st Figure 1 Tank body 2 Feed pipe 3 Return pipe 4/Tsurubo knob 6 Fuel supply device 7/Branch pipe 8 Flow path switching means! ■ Ejector pop 12/nozzle] 3 Chatuba Figure 3 Figure 4

Claims (1)

[Claims] (1) A branch pipe is installed downstream of the fuel pump of the feed pipe that sends the fuel in the tank body to the fuel supply device by the operation of the fuel pump, and the deceleration at the time of a vehicle collision is detected at the branch part of this branch pipe. , a flow path switching means is provided to switch the supply of fuel discharged from the fuel pump from the fuel supply device side to the branch pipe side, and an ejector pump is provided within the tank body to eject the working fluid of the ejector pump. A fuel system structure for a vehicle, characterized in that the branch pipe communicates with the nozzle for the ejector pump, and a return pipe for returning excess fuel from the fuel supply device to the tank body communicates with the chamber for introducing the actuated fluid of the ejector pump. .