JPH08135529A - Negative pressure inlet path in multiple throttle body - Google Patents

Abstract

PURPOSE: To reduce a piping space and cost by using a simple construction not using collective piping. CONSTITUTION: A negative pressure inlet groove part 7 which interconnects intake 4 and also interconnects a negative pressure communication path 10 on the outside of a body is formed a mating surface 3a downstream from a multiple throttle body having the intake paths 4 independent for each cylinder of an engine. Also the multi-throttle body is connected to an engine head for an opening part of the negative pressure inlet part 7 on the mating surface side to be covered by the mating surface of the engine head.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiple throttle body having an independent intake passage for each cylinder of an engine and introducing a negative pressure of a multiple throttle body communicating with a negative pressure communication passage leading to an intake pipe pressure sensor or the like. Regarding the passage.

[0002]

2. Description of the Related Art A conventional multiple throttle body is used in an LJ type electronically controlled fuel injection system for controlling an amount of intake air by controlling an amount of intake air. There is an intake passage demarcation member disclosed in Japanese Patent No. 180106. By the way, the pressure of the intake manifold is measured, the intake air amount is calculated, and fuel injection is performed.
When considering a multiple throttle body used in a -J type electronically controlled fuel injection system, a crankcase ventilation passage 8 (reference numeral in the publication, the same applies hereinafter) for power steering in the conventional multiple throttle body. In addition to the communication passage 2 to which auxiliary air supply passages such as the idle-up passage 6, the air-conditioner idle-up passage 7, and the passage 5 from the idle speed control device are connected,
A negative pressure introducing passage is required to newly measure the intake pipe pressure.

[0003]

Therefore, it may be easy to connect the negative pressure introducing passage to the communicating passage 2. However, since the communicating passage 2 is connected to the passage 8 having a crankcase ventilation valve. The blow-by gas may flow into the negative pressure introduction passage, and the intake pipe pressure sensor provided in the passage may be damaged. Therefore, the negative pressure introduction passage needs to be provided in a system different from that of the communication passage 2. In this case, a structure in which a collecting pipe that individually communicates with each intake passage is connected to the outside of the throttle body by a conventional general collecting pipe system requires a large piping space and is not a preferable measure. Negative pressure extraction of the multiple throttle body must be introduced from all cylinders because it is necessary to measure the accurate intake air amount.

The technical problem to be solved by the present invention is as follows.
It is an object of the present invention to provide a negative pressure introduction passage for a multiple throttle body that can reduce piping space and cost by adopting a simple structure that does not use a collecting pipe.

[0005]

According to a first aspect of the invention for solving the above-mentioned problems, the intake passages are mutually connected to a downstream side mating surface of a multiple throttle body having an independent intake passage for each cylinder of the engine. A negative pressure introducing passage of a multiple throttle body, characterized in that a negative pressure introducing groove communicating with a negative pressure communicating passage outside the body is formed. According to a second aspect of the present invention, a negative pressure outlet is provided in the center of the negative pressure inlet groove so as to communicate with the negative pressure communication passage, and the negative pressure inlet groove has a substantially symmetrical shape with respect to the negative pressure outlet. The negative pressure introducing passage of the multiple throttle body according to claim 1. According to a third aspect of the present invention, in the multiple throttle body in which the injection port portion of the injector is provided on the mating surface on the downstream side, the opening portion on the intake passage side of the negative pressure introduction groove portion is arranged at a position farther from the injection port portion. The negative pressure introducing passage of the multiple throttle body according to claim 1 or 2.

[0006]

According to the negative pressure introducing passage of the multiple throttle body of the first aspect of the invention, by connecting the multiple throttle body to the downstream side connecting member, the opening on the mating surface side of the negative pressure introducing groove is located on the downstream side. Blocked by the mating surfaces of the connecting members,
As a result, the intake passages are communicated with each other and the negative pressure communication passages outside the body are communicated with each other, so that the structure is simple without using a conventional collecting pipe. According to the negative pressure introducing passage of the multiple throttle body of the second aspect of the invention, the length of the negative pressure introducing passage from the opening on each intake passage side to the negative pressure extracting port is balanced. According to the negative pressure introducing passage of the multiple throttle body of the third aspect of the invention, since the opening on the side of each intake passage is located farther than the injection port of the injector, the introduction negative pressure is affected by the fuel injection pressure of the injector. Hateful.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. A multiple throttle body used in a four cylinder engine is shown in FIG. 3 in a front view and in FIG. 4 in a side view.
The multiple throttle body 1 includes a body 2 independent of each cylinder, and an intake flange 3 connected to the downstream end surface of the body 2 by a bolt or the like (not shown).

FIG. 2 is an explanatory view showing a side surface of the multiple throttle body 1 which is partially broken. The body 2 and the intake flange 3 form a series of independent intake passages 4 for each cylinder of a 4-cylinder engine. A throttle valve 5 that opens and closes each intake passage 4 is rotatably supported by the body 2 via a shaft 5a. Further, an injector 6 for injecting fuel into each cylinder is attached to the intake flange 3. Although not shown, a surge tank is connected to the upstream mating surface of the body 2 and an engine corresponding to the downstream connecting member shown by the two-dot chain line in FIG. 2 is connected to the downstream mating surface of the intake flange 3. The head 13 is connected.

In addition to FIG. 2, in FIG. 1 showing a downstream side mating surface of the multiple throttle body 1, a negative pressure introducing groove portion for communicating the respective intake passages 4 is formed on the downstream side mating surface 3a of the intake flange 3. 7 is provided. At the center of the negative pressure introducing groove portion 7, a substantially L-shaped negative pressure outlet 8 is formed which communicates with the outside of the body. A hose connecting tube 9 is attached to the open end of the negative pressure outlet 8, and a negative pressure communication passage 10 connected to the intake pipe pressure sensor 11 is connected to the tube 9.

As shown in FIG. 1, the negative pressure introducing groove portion 7 is formed in a substantially symmetrical shape around the negative pressure outlet 8. For details, check each cylinder in sequence from left to right in Figure 1.
1, # 2, # 3, and # 4, the injection port portions 12 of the injector 6 in the cylinders # 1 and # 2 are arranged symmetrically at positions close to the cylinders.
Nozzle portion 12 of the injector 6 in both cylinders # 4
Similarly, as described above, the cylinders are arranged substantially symmetrically at positions close to each other. # 1, # 2, # of the negative pressure introducing groove portion 7
The openings a to d of the intake passages 3 and # 4 on the side of the intake passage 4 are arranged at positions farther from the injection port portion 12 of the injector 6, and the negative pressure introduction groove portion 7 thereof has the openings a and b of # 1 and # 2. An arcuate portion 71 connecting in a substantially arcuate shape, and openings c and d of # 3 and # 4.
Is provided with an arcuate portion 72 that connects the arcuate portions in a substantially arcuate shape, and a linear portion 73 that linearly connects the arcuate portions 71, 72 in the tangential direction thereof. An outlet 8 is arranged.

According to the negative pressure introducing passage of the multiple throttle body 1, by connecting the multiple throttle body 1 to the engine head 13, the opening of the negative pressure introducing groove portion 7 on the mating surface side is aligned with the engine head 13. It is closed by a surface, which allows the intake passages 4 to communicate with each other and the negative pressure communication passage 10 outside the body to communicate with each other. Since a conventional collecting pipe is not required, the structure is simple, and the piping space is reduced. In addition, the cost can be reduced. Further, the negative pressure pulsation can be prevented by balancing the negative pressure introducing passage lengths from the openings a, b, c, d on the side of each intake passage 4 to the negative pressure outlet 8. This is suitable for accurate detection by the intake pipe pressure sensor 11. Further, the openings a, b, c, on the intake passage 4 side,
Since d is located farther from the injection port 12 of the injector 6, the introduction negative pressure is unlikely to be affected by the fuel injection pressure of the injector 6, and therefore the intake pipe pressure sensor 11 can perform accurate detection. The negative pressure communication passage communicating with the negative pressure introducing passage is not limited to the passage communicating with the intake pipe pressure sensor 11.

[0012]

According to the negative pressure introducing passage of the multiple throttle body of the first aspect of the invention, the multiple throttle bodies are connected to the downstream side connecting member so that the intake passages are communicated with each other and are connected to the outside of the body. Since the pressure communication passages are communicated with each other, the structure is simpler than that using a conventional collecting pipe, so that the piping space can be reduced and the cost can be reduced. According to the negative pressure introduction passage of the multiple throttle body of the invention of claim 2, the negative pressure pulsation is prevented by balancing the negative pressure introduction passage length from the opening on each intake passage side to the negative pressure outlet. You can According to the negative pressure introducing passage of the multiple throttle body of the invention of claim 3, the introduced negative pressure is less likely to be affected by the fuel injection pressure of the injector. Therefore, for example, when the negative pressure for measuring the intake pipe pressure is obtained, the accuracy is high. Can detect.

[Brief description of drawings]

FIG. 1 is a view showing a downstream side mating surface of a multiple throttle body.

FIG. 2 is an explanatory view showing a side surface of a multiple throttle body which is partially broken.

FIG. 3 is a front view of a multiple throttle body.

FIG. 4 is a side view of a multiple throttle body.

[Explanation of symbols]

 1 Multiple throttle body 2 Body 3 Intake flange 3a Downstream mating surface 4 Intake passage 7 Negative pressure introducing groove 8 Negative pressure outlet 10 Negative pressure connecting passage 13 Engine head

Claims (3)

[Claims] 1. A negative pressure introduction system that connects the intake passages to each other and a negative pressure communication passage outside the body to a mating surface on the downstream side of a multiple throttle body having an independent intake passage for each cylinder of the engine. Negative pressure introduction passage of multiple throttle body characterized by forming a groove. 2. A negative pressure outlet opening for communicating a negative pressure communication passage is arranged in the center of the negative pressure inlet groove portion, and the negative pressure inlet groove portion has a substantially symmetrical shape with the negative pressure outlet opening as a center. The negative pressure introducing passage of the multiple throttle body according to claim 1. 3. A multiple throttle body in which an injector nozzle portion is provided on a downstream mating surface, wherein an opening of the negative pressure introducing groove portion on the intake passage side is arranged at a position farther from the nozzle hole portion. The negative pressure introducing passage of the multiple throttle body according to claim 1 or 2.