JPH0240871B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to improvements in diaphragm fuel pumps, and more particularly to a diaphragm fuel pump using a combination valve made of an elastic material.

(Prior Art) Automotive fuel pumps are strongly required to be lighter and smaller, and a chamber formed by drawing a metal plate is used.

On the other hand, there is also a demand for miniaturization of suction valves and discharge valves, and it is also known that a rubber umbrella valve is used and the umbrella part functions as a check valve.

On the other hand, a composite valve has also been proposed in which a single valve body functions as both a suction valve and a discharge valve.

(Problems to be Solved by the Invention) However, when this composite valve is used in a diaphragm fuel pump, various difficulties must be solved, and various measures are required to solve this problem.

For example, in a diaphragm fuel pump, the discharge chamber (desirably, the suction chamber also has some volume) needs to have a certain size in order to prevent fuel pulsation. Furthermore, the suction chamber and the discharge chamber must be made as compact as possible to reduce the overall size and weight. Furthermore, the sealing between the suction side and the discharge side must be ensured. Furthermore, it must be easy to assemble.

In order to solve the technical issues mentioned above, it is important to consider where the composite valve should be installed and how the suction chamber and discharge chamber should be laid out.
Various considerations must be made.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to effectively incorporate a compound valve into a diaphragm fuel pump using a chamber formed by drawing a metal plate to further reduce the size of the pump.
The goal is to achieve weight reduction.

(Means for Solving the Problems) In order to achieve the above object, the present invention is configured as follows.

That is, the present invention provides an inch yambar passing through the center of the outchamber, and forms a suction chamber between the periphery of the inch yamba and the outchamber,
A valve mounting member is hermetically attached to the open end of the inch chamber on one side, the valve mounting member is sealingly attached to the inner periphery of the out chamber on the other hand, the valve attachment member is provided with an opening circumferentially, and has an umbrella portion on the periphery. and a composite valve having a one-way valve portion in the center is provided to open and close an opening formed in the valve mounting member,
The outchamber is configured by caulking the diaphragm to the flange portion of the lower body.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

An out chamber 4 is caulked to a flange 2 of a lower body 1 made of cast metal, sandwiching the peripheral edge of a diaphragm 3. The outchamber 4 is formed by drawing and forming a metal plate, and has a suction pipe 5 penetratingly held on the side surface thereof. An inch bow 7 is held through the top surface 6 of the out chamber 4.
Both the suction pipe 5 and the inch bower 7 are attached to the outchamber 4 by brazing means, but it is also possible to use other attachment means.

The enlarged diameter cylindrical open end 8 of the inch bower 7 is located within the out chamber 4, and a valve mounting member 9 is in sealing abutment with the open end 8 of the inch bow 7 on the one hand via a seal 10, and on the other hand in the out chamber 4. Press-fitted into the inner periphery.

The valve mounting member 9 has a mounting port 11 in the center,
A plurality of openings 12 are provided at positions on the outer periphery of the open end 8 of the inch bow 7.

The composite valve 13 consists of an umbrella part 14 at the periphery, a one-way valve part 15 at the center, and a base part 16. The one-way valve part 15 is inserted into the mounting opening 11, and the umbrella part 14 covers the opening 12 to open and close. , the base 16 is connected to the mounting port 11
is installed in a sealed manner.

For the valve mounting member 9, an appropriate material such as synthetic resin or cast iron may be selected, but synthetic resin is preferable from the viewpoint of cost and weight.

The diaphragm 3 is fixed to the pull rod 18,
Its peripheral edge is caulked so as to be sandwiched between the end of the outchamber 4 and the flange 2 of the lower body 1. The pull rod 18 is reciprocated by a rocker arm 19.

The inch bower 7 is shaped like a tip and is penetrated with a portion remaining outside the top surface 6 of the outer bower 4.

A discharge pipe 20 is provided passing through the side surface of the inch bow 7 on the outside of the top surface 6. In addition,
The discharge pipe 20 can also be provided so as to penetrate the top surface 21 of the inch bow 7.

In the structure of the composite valve 13 described above, the one-way valve part 15 has the distal end 22 crushed and constricted, and extends upward from the base part 16.

In the present invention configured as described above, the fuel pump operates as follows.

The pull rod 18 is reciprocated by the rocker arm 19, and the diaphragm 3 is reciprocated. When the diaphragm 3 moves downward, the fuel being sucked into the suction chamber 23 via the suction pipe 5 expands the umbrella portion 14 of the composite valve 13 and is sucked into the pump chamber 24 through the opening 12.

Subsequently, when the diaphragm 3 moves upward, the umbrella part 1
4 closes the opening 12, and the tip of the one-way valve portion 15 is expanded by the fuel, and the fuel is introduced into the discharge chamber 25. Thereafter, the fuel is delivered to a carburetor (not shown) through the discharge pipe 20.

(Effects of the Invention) The effects of the present invention explained above are listed below.

Suction pipes, discharge pipes, inch bars, etc. are installed by brazing, but when plating work is performed after brazing, each part is in an open state, so the structure is such that it becomes a hindrance to plating work. do not have. Therefore, the overall manufacturing process is simplified and costs are reduced.

Further, since the one-side valve portion of the composite valve is oriented upward, the diaphragm can be brought close to the composite valve as far as possible, and the volume inside the pump chamber can be made as small as possible, thereby improving pump efficiency.

Since it is easy to increase the volume of the discharge chamber, pulsation of fuel supply can be reduced.

The equipment is well-balanced as the intake is taken in through the peripheral opening and discharged through the one-way valve in the center.
There are fewer abnormal noises and abnormal vibrations, and durability is improved.

The suction chamber and the discharge chamber can be reliably sealed, and the pump chamber, the suction chamber, and the discharge chamber can be reliably sealed.

The valve mounting member is provided with a composite valve, and the valve mounting member is press-fitted to the outside chamber and sealed to the inch chamber through a seal, which simplifies assembly and provides reliable sealing.

[Brief explanation of drawings]

The figure is a sectional view showing one embodiment of the present invention. 1: Lower body, 3: Diaphragm, 4: Out chamber, 7: Inch chamber, 9: Valve mounting member, 13: Complex valve.

Claims (1)

[Claims] 1. An inch bow is provided through the center of the out chamber, a suction chamber is formed between the periphery of the inch bow and the out chamber, and a valve mounting member is sealingly attached to the open end of the inch bow on the one hand;
On the other hand, the valve mounting member is hermetically mounted to the inner periphery of the outchamber, the valve mounting member is provided with an opening around the circumference, and a composite valve having an umbrella portion on the periphery and a one-way valve portion in the center is attached to the valve mounting member. A diaphragm type fuel pump characterized in that an opening formed in the outer chamber is provided to open and close, and the outer chamber is caulked to a flange portion of a lower body by sandwiching a diaphragm therebetween.