JP2000345942A - Fuel supplying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel supplying device having a delivery pipe having an improved function, and capable of being easily mounted. SOLUTION: A plurality of injectors 2 are fitted to the side surface of a delivery pipe 1, a gas pressure sensor 7 is arranged on one end surface of the delivery pipe 1, a gas temperature sensor 8 is arranged on the other end surface, a fuel supplying port 9 is provided on the side surface of the delivery pipe 1, and mounting stays 11 are fixed between respective injectors 2, 2 on the side surface of the delivery pipe 1. A gas passage in the delivery pipe 1 is shortened to restrain the variation in performance of cylinders. Since sensing surfaces 7a, 8a of both sensors are provided on the passage so as to be faced to each other, measurement is accurately performed. Further, manufacture of the delivery pipe 1 is facilitated, the weight balance is improved, and mounting work is facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION Natural gas (CNG) is used for vehicles.
Engines that use fuel are also used. Fuel is distributed to each cylinder by a delivery pipe. Some fuel pressure control devices are provided to control fuel pressure fluctuations. The present invention relates to a fuel supply device provided with such a delivery pipe.

[0002]

2. Description of the Related Art In an automobile using natural gas (CNG) as a fuel, an engine having a structure in which fuel is injected into a combustion chamber by an injector has a fuel temperature,
Engine performance varies with fuel pressure. Therefore, as a fuel supply device, a structure has been proposed in which a fuel pressure regulator is attached to a delivery pipe for supplying fuel to a plurality of injectors, and the fuel gas pressure device has a large variation in fuel gas pressure.

[0003] Conventionally, a delivery pipe of a fuel supply device is directly connected to a plurality of injectors for injecting fuel into a combustion chamber. Therefore, the delivery pipe extends along a cylinder of the engine and is structurally attached to an intake manifold. As an example, the inside of the delivery pipe has a double structure, two passages are arranged side by side, a fuel supply port and an adjustment discharge port are provided on one end face of the delivery pipe, and a pressure regulator is attached to an end face on the opposite side of the passage return. Have been proposed (see Japanese Patent Application Laid-Open Nos. H7-167008 and 8-82268).

[0004] When a delivery pipe is directly connected to an injector, a structure has been proposed in which an electromagnetic coil portion of the injector is inserted into the delivery pipe and integrally connected, and electrical wiring is connected from an end face of the delivery pipe ( See JP-A-9-112386 and JP-A-10-184490).

[0005]

By the way, when attaching a long delivery pipe installed along the cylinder of the engine, since the both end faces of the delivery pipe described above have different structures, the delivery pipe has a different structure. The applied load becomes non-uniform, and it is necessary to select the position of the tightening screw from the viewpoint of strength, which causes a restriction on the layout. In addition, even when a pressure regulator or a sensor is mounted near the injector, the space near the intake manifold to which the delivery pipe is mounted is often narrow and difficult to mount. Further, even when the delivery pipe is attached, if the weight balance is poor, it is not easy to support the temporary fixing or the like, and the assembling work is troublesome.

[0006] It is an object of the present invention to provide a fuel supply device in which the function of a delivery pipe is enhanced and the installation is easy.

[0007]

In order to achieve the above object, according to the present invention, an injector hole for fitting a plurality of injectors is provided on a side surface of a delivery pipe mounted on an engine and a fuel is provided. A supply port is provided, and a fuel temperature sensor is provided on one end surface of the delivery pipe, and a fuel pressure sensor is provided on the other end surface. Further, when the fuel supply port is provided on the side surface near the fuel pressure sensor provided at one end of the delivery pipe, the temperature and pressure of the fuel gas can be measured efficiently.

A second aspect of the present invention is characterized in that, in the first aspect of the present invention, the end face of the sensing portion of the fuel pressure sensor is disposed substantially on the same plane as the edge of the injector hole on the fuel pressure sensor side.

[0009] The invention of claim 3 is claim 1 or claim 2.
In the invention, the delivery pipe is formed with a fuel chamber having a uniform cross section inside, and the fuel chamber is provided with a sensing part of a fuel pressure sensor.

[0010] The invention of claim 4 is the invention of claims 1 to 3.
The invention according to any one of the above, characterized in that a mounting stay is connected between adjacent injector fitting positions of the delivery pipe. The invention of claim 5 is claim 1
The invention according to any one of claims 4 to 6, wherein the mounting stay of the delivery pipe is fastened to a reinforcing stay of the intake manifold.

The invention of claim 6 is the invention of claims 1 to 5
In the invention described in any one of the above, a gas temperature sensor is installed as a fuel temperature sensor, and a gas pressure sensor is installed as a fuel pressure sensor.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the structure of a fuel supply device that injects fuel (gas) into each combustion chamber of the engine, FIG.
As shown in (a), fuel (gas) is distributed to injectors 2 of each combustion chamber by a delivery pipe 1 on the supply side. Injector holes 1a are formed at substantially equal intervals on the side surface of the long delivery pipe 1, and a cylindrical injector cap 3 is fitted into the injector hole 1a. The tip of the injector cap 3 is enlarged so that the insertion portion of the injector 2 can be easily fitted. An O-ring 4 is attached to an insertion portion of the injector 2.

[0013] Further, casings 5 and 6 are attached to both ends of the delivery pipe 1, and a gas pressure sensor 7 and a gas temperature sensor 8 are respectively mounted by screwing. Since the end of the casing 5 of the gas pressure sensor 7 is caulked, the casing 5 is attached to the delivery pipe 1 by having a narrowed portion at the end and fitting the narrowed portion to the end of the delivery pipe 1. ing. The throttle portion of the gas pressure sensor 7 is disposed apart from the end of the injector hole 1a on the gas pressure sensor 7 side. The casing 6 of the gas temperature sensor 8 has a fitting portion that matches the inner peripheral surface of the delivery pipe 1, and the casing 6 is attached to the delivery pipe 1 by fitting the fitting portion to the end of the delivery pipe 1. ing. Further, the sensing portion end surface 8a of the gas temperature sensor 8 is projected from the fitting portion, and the sensing portion end surface 8a is brought close to the gas temperature sensor 8 side edge of the injector hole 1a on the gas temperature sensor 8 side.

A fuel supply port 9 is provided on another side of the delivery pipe 1 on the side close to the gas pressure sensor 7. The mounting holes of the casings 5 and 6 of the sensors 7 and 8 have different sizes to prevent the mounting positions of the sensors 7 and 8 from being mixed up. Also, the O-ring 10 mounted on the end of the screw face is adjusted to the respective diameter.
A combustion chamber having a uniform cross-sectional area is formed inside the delivery pipe 1, and both ends are provided with a casing 6 of the gas temperature sensor 8.
And the casing 5 of the gas pressure sensor 7.

The injector caps 3 are provided at substantially equal intervals in the delivery pipe 1, and a mounting stay 11 is fixed between adjacent injector caps 3. Further, the injector 2 has an injector cover.
12 (see FIG. 5) is attached. As shown in FIGS. 3 to 5, a reinforcement stay 15 is fixed to the intake manifold 13 with screws 16 so as to reinforce the branch 14.
When the delivery pipe 1 is mounted on the engine, the mounting stay 11 of the delivery pipe 1 is fastened to the reinforcing stay 15 with the screw 17. Reference numeral 18 shown in FIG. 4 is a cylinder head 18 of the engine.

Next, the operation of the fuel supply device thus configured will be described. First, since the gas pressure sensor 7 and the gas temperature sensor 8 are provided at both ends of the delivery pipe 1 by screwing, the arrangement of the gas pressure sensor 7 and the gas temperature sensor 8 is on the same axis, and such a structure is set. This facilitates processing of the end of the delivery pipe 1. Further, since both sensors 7 and 8 are arranged on the end face of the delivery pipe 1, there is no need to prepare a blind lid. In addition, since the sensing part of the gas temperature sensor 8 is brought close to the sensor side edge of the injector hole 1a, it is difficult for a gas reservoir to be formed around the sensor side end of the injector hole 1a, so that the temperature can be measured accurately. become able to.

In addition, this arrangement increases the space at the intermediate portion of the delivery pipe 1, and the mounting stay 11 can be provided at this location. Further, the mounting stay 11 can be fastened to the reinforcing stay 15 for improving the strength of the branch 14 of the intake manifold 13. Since the weight of the delivery pipe 1 is substantially equal in the longitudinal direction, the weight balance is good, the load applied to the mounting stay 11 is substantially equal, and the work of mounting the delivery pipe 1 to the intake manifold 13 becomes easy. By mounting the delivery pipe 1 on the reinforcing stay 15, the branch 14 of the intake manifold 13 is also strengthened.

Further, since the space between the injectors 2 and 2 is widened, it is easy to attach the injector cover 12, and thus a soundproof effect can be obtained. When the delivery pipe 1 is mounted on the intake manifold 13, the shape of the gap therebetween changes depending on the shape of the injector cover 12. However, since the mounting stay 11 and the reinforcing stay 15 are interposed, the screw tightening position can be freely changed. can do.

Further, since fuel flows from the fuel supply port 9 on the side surface of the delivery pipe 1 to the injector 2 mounted on the other side surface, the fuel flow path is shortened, the temporal variation is reduced, and the fuel flow is stabilized for each cylinder. Amount can be injected. Further, the gas pulsation in the delivery pipe 1 entering the injector 2 is also sensed by the gas pressure sensor 7 near the fuel supply port 9, and the gas pressure can be measured. Further, the sensing section end face 8a of the gas temperature sensor 8 is arranged on the end face of the delivery pipe 1 facing the fuel flow path, so that the gas temperature can be accurately measured. The fuel supply can be adjusted by the signals from the sensors 7 and 8, and the operation of the engine can be performed smoothly.

Another embodiment of the present invention will be described with reference to FIG. In the delivery pipe 1 used in the fuel supply device, in the above configuration, as shown in FIG. 1B, the end of the casing 5 of the gas pressure sensor 7 is separated from the injector hole 1a, so that the vicinity of the end is A gas reservoir m is formed around the gas pressure sensor 7, and the pressure of the fuel in the gas reservoir m may be different from the pressure of the injected fuel.
Further, the casing 5 of the gas pressure sensor 7 shown in FIG.
Since the end of the casing 5 is caulked and attached to the delivery pipe 1, a throttle portion is formed between the combustion chamber and the sensing section. For this reason, a difference occurs between the gas pressure in the combustion chamber and the gas pressure in the delivery pipe 1 due to the influence of the throttle portion.

In another embodiment of the present invention, as shown in FIG. 2, both ends of the delivery pipe 1 are formed with threaded surfaces 1b and 1b 'in inner holes of different sizes, respectively. The gas temperature sensor 8 is inserted for a predetermined length. Positioning of each sensor 7 and 8 is performed with screw surface 1b, 1b '
As straight screws for accuracy. An injector hole 19 is integrally formed on the side surface of the delivery pipe 1, and the sensing unit end face 7 a of the gas pressure sensor 7 is disposed on substantially the same plane as the gas pressure sensor 7 side edge of the injector hole 19. At the same time, the end of the insertion port of the gas pressure sensor 7 in the delivery pipe 1 was brought close to the injector hole 19. Further, both ends in the delivery pipe 1 are partitioned by a gas temperature sensor 8 and a gas pressure sensor 7 to provide a fuel chamber a having a substantially uniform cross-sectional area. An end face 7a is provided. That is, the fuel chamber a is formed by inserting the sensing part end face 7a in the delivery pipe 1 of the gas pressure sensor 7 and the sensing part end face 8a in the delivery pipe 1 of the gas temperature sensor 8 into the insertion diameter r of the adjacent injector hole part 19. And a space between the sensing portion end face 7a and the sensing portion end face 8a. Further, when the gas pressure sensor 7 and the gas temperature sensor 8 are mounted, the insertion diameters in the delivery pipe 1 are different, so that the assemblability is improved. A fuel chamber a having a uniform sectional area is formed.

As described above, the gap around the sensing portion of the gas pressure sensor 7 is reduced, and the gas reservoir m is not formed between the gas pressure sensor 7 and the adjacent injector hole portion 19, so that the gas pool can be prevented. The pressure of the gas can be measured more accurately. Further, since there is no throttle at the end of the gas pressure sensor 7 in the delivery pipe 1 and there is no pressure fluctuation that can be caused by the gas passing through the aforementioned throttle, the gas pressure in the delivery pipe 1 can be more accurately measured. Can be measured.

[0023]

The present invention is as described above. According to the first aspect of the present invention, the fuel is supplied from the side of the delivery pipe and distributed to the injector, so that the distance between the fuel supply port and the injector is reduced. Can be shortened. As a result, performance variations among the cylinders of the engine can be suppressed. Further, since the fuel temperature sensor and the fuel pressure sensor are arranged at both ends of the delivery pipe, the production of the delivery pipe is facilitated. Further, the weight balance is improved, the strength is maintained, and the work of attaching the fuel supply device to the engine is facilitated. Further, productivity can be improved. Further, since the gas pulsation sensor detects the fuel pulsation in the delivery pipe, the fuel pressure can be accurately measured.

According to the second aspect of the present invention, since the sensing portion end face of the fuel pressure sensor is disposed on substantially the same plane as the edge of the injector hole on the fuel pressure sensor side, the delivery pipe is provided at the fuel pressure sensor side end. A gas reservoir is less likely to be formed, and the pressure of the injected gas can be measured more accurately. According to the third aspect of the present invention, since the combustion chamber having a substantially uniform cross-sectional area is formed in the delivery pipe, the pressure in the delivery pipe can be accurately measured.

According to the fourth aspect of the present invention, since the mounting stay is coupled between the adjacent injector fitting positions of the delivery pipe, the delivery pipe can be compactly mounted on the intake manifold, and the empty space is effectively used. Can be used for In the invention described in claim 5, the mounting stay of the delivery pipe is tightened to the reinforcing stay of the intake manifold. Therefore, when the injector cover is mounted, the mounting screw position is changed even if the shape and position of the mounting gap are changed. It is possible to do. Thereby, the soundproofing effect of the injector can be improved. In the invention according to claim 6, since the gas pressure sensor and the gas temperature sensor are installed in the delivery pipe, the pressure and temperature of the fuel of the engine using natural gas can be measured. The engine can be operated efficiently.

[Brief description of the drawings]

FIG. 1 is a sectional view of an entire delivery pipe (a) and a main part (b) of a delivery pipe according to an embodiment of the present invention.

FIG. 2 is a sectional view of a delivery pipe according to another embodiment of the present invention.

FIG. 3 is an assembly diagram of the delivery pipe according to the embodiment of the present invention.

FIG. 4 is a side view showing an assembled state of the delivery pipe according to the embodiment of the present invention.

FIG. 5 is an exploded view of an assembly location of the delivery pipe according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Delivery pipe 1a Injector hole 2 Injector 3 Injector cap 7 Gas pressure sensor 7a Sensing part end face 8 Gas temperature sensor 8a Sensing part end face 9 Fuel supply port 11 Mounting stay 13 Intake manifold 15 Reinforcement stay r Insertion diameter

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02B 43/00 F02B 43/00 A F02M 21/02 F02M 21/02 L SX 37/00 321 37/00 321B 65/00 307 65/00 307

Claims (6)

[Claims] An injector hole for fitting a plurality of injectors is provided on a side face of a delivery pipe mounted on an engine, a fuel supply port is provided, a fuel temperature sensor is provided on one end face of the delivery pipe, and a fuel pressure sensor is provided on the other end face. A fuel supply device provided with a sensor. 2. The fuel supply device according to claim 1, wherein an end face of the sensing portion of the fuel pressure sensor is disposed on substantially the same plane as an edge of the injector hole on the fuel pressure sensor side. 3. The fuel delivery system according to claim 1, wherein a fuel chamber having a uniform cross section is formed in the delivery pipe, and a sensing part of a fuel pressure sensor is disposed in the fuel chamber. Fuel supply system. 4. The fuel supply device according to claim 1, wherein a mounting stay is connected between adjacent injector fitting positions of the delivery pipe. 5. The fuel supply device according to claim 1, wherein an attachment stay of the delivery pipe is fastened to a reinforcement stay of the intake manifold. 6. The fuel supply device according to claim 1, wherein a gas temperature sensor is provided as the fuel temperature sensor, and a gas pressure sensor is provided as the fuel pressure sensor.