JPH0232866Y2 - - Google Patents

Description

[Detailed Description of the Invention] <<Industrial Application Field>> This invention relates to a fuel filter inserted into a fuel supply system of an internal combustion engine.

<<Prior Art>> Some fuel filters inserted into the fuel supply system of diesel engines used in automobiles and the like are attached integrally with a priming pump. FIG. 1 shows an example of a conventional mounting structure.

In the figure, 1 is a priming pump, 2 is a fuel filter, and the fuel filter 2 is attached to a cylindrical part 3 protruding from the center of the lower part of the priming pump 1 by screwing its center part,
It consists of a cylindrical case 4 whose peripheral edge is liquid-tightly fixed to the priming pump 1, and a filter element 5 disposed within the case 4. The outer periphery of the filter element 5 communicates with an inlet A provided on the side of the priming pump 1, and the inner periphery communicates with an outlet B formed at the center of the cylindrical portion 3.

Further, the priming pump 1 is provided with a diaphragm 6 and a pair of check valves 7 and 8 below, and the fuel supplied from the inlet A by the reciprocation of the piston 9 flows from the outer circumference to the inner circumference of the filter element 5. After passing through, it is discharged from the outlet B side.

However, the fuel filter having such a structure has the following technical problems.

<Problems to be Solved by the Invention> In other words, in the above structure, the pair of check valves 7 and 8 must be provided in a portion of the priming pump 1 that has many bends, which complicates the structure.

Further, when replacing the element 5 in the filter 2, it is removed from the cylindrical portion 3, but at this time, fuel tends to leak from the filter 2.

This idea was devised in view of the above problems, and eliminates the need for a check valve on the discharge side of the priming pump, thereby simplifying and downsizing the pump structure and preventing fuel leakage when replacing the filter. The purpose is to prevent

<Means for Solving the Technical Problems> In order to achieve the above object, this invention incorporates a priming pump in which a fuel pressure feeding path and a fuel outlet are formed, and a filter element.
A fuel filter comprising a case with an open end, an end plate and a mounting plate attached to the opening of the case, and the priming pump is screwed onto the mounting plate to integrate the fuel filter, the inlet of the fuel pumping path. a check valve provided in the filter element; a communication hole provided in the mounting plate and communicating with the fuel pumping path; and a check valve provided inside the communication hole on the filter element side. It is characterized by consisting of.

<<Example>> Hereinafter, a preferred example of this invention will be described in detail using the drawings.

FIG. 2 shows an embodiment of the fuel pump according to this invention.

In the same figure, 10 is a priming pump;
1 is a fuel filter.

The priming pump 10 is provided with a fuel pressure feeding path as in the prior art, and this path has an inlet A that opens on the side.

Further, a cylindrical portion 12 is formed at the center of the lower part of the priming pump 10, and a fuel outlet B is provided inside the cylindrical portion 12, and a diaphragm 13
and a manual piston 14 whose center is connected to a diaphragm 13, and a check valve 15 only in the vicinity of the inlet A.

The filter 11 consists of a cylindrical case 16, a cylindrical filter element 17 housed in the case 16, and a central cylindrical portion 18a located above the case 16 and connected to the inner cylindrical portion of the filter element 17. A mounting plate 18 that fits and has its peripheral edge connected to the case 16; and an end plate 19 provided with a gasket portion 19a that is caulked to the upper edge of the case 16 and is liquid-tightly connected to the bottom peripheral edge of the priming pump 10. It is made up of

The cylindrical portion 18a of the mounting plate 18 is screwed to the cylindrical portion 12 of the priming pump 10, and a circulation hole 18b communicating with the fuel pressure passage of the priming pump 10 is formed at the periphery of the cylindrical portion 18a. The fuel that has entered the chamber of the priming pump 10 is introduced into the case 16 through the check valve 15 and through the flow hole 18b.

The flow hole 18b is closed by a rubber check valve 20 (check valve) provided inside the case 16 to prevent backflow.

The rubber check valve 20 is fixed by fitting the center into the cylindrical portion 18b, and contacts the inside of the flow hole 18b, and maintains a predetermined gap between it and the upper end of the filter element 17 by the ring-shaped spacer 21. It is well located.

With the above configuration, a pair of check valves 15 and 20 are configured in the pressure feeding path between the inlet A of the priming pump 10 and the element 17 of the fuel filter 11, and due to the pressing action of the piston 14, As shown by the arrow, the fuel introduced from the outlet A side closes the check valve 15, pushes open the rubber check valve 20 provided on the flow hole 18b side, enters the outer periphery of the case 16, and passes through the filter element 17. Then, it is discharged from the inside to the outlet B side.

Also, when the piston 14 is pulled, the rubber check valve 20 closes, contrary to the above, and the check valve 1
5 opens to introduce fuel into the pump chamber.

By alternately opening and closing the valves 15 and 20 in this manner, fuel can be pumped in only one direction.

<<Operations and Effects of the Invention>> As is clear from the above explanation, the fuel filter according to the invention eliminates the need for at least one check valve on the priming pump side to which it is attached. The mechanism of the priming pump can be simplified and downsized.

In addition, when replacing the fuel filter, the fuel or moisture contained in the case will not leak out due to the built-in check valve, so there are advantages such as no need to worry about replacing the fuel filter. be.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a conventional fuel filter and priming pump mounting structure, and FIG. 2 is a sectional view showing a fuel filter and priming pump mounting structure according to this invention. 10...Priming pump, 11...Fuel filter, 12...Cylinder part, 13...Diaphragm,
14...Manual piston, 15...Check valve, 16...
...Case, 17...Filter element, 18...
...Mounting plate, 18a...Cylinder part, 18b...
Communication hole, 19...end plate, 19a...gasket portion, 20...rubber check valve, 21...ring-shaped spacer.

Claims (1)

[Scope of utility model registration request] A priming pump in which a fuel pressure feeding path and a fuel outlet are formed, a case with a built-in filter element and an open end, and an end plate and a mounting plate that are attached to the opening of the case, and the mounting plate The fuel filter is integrated with the priming pump by screwing the priming pump thereon, a check valve provided only at the entrance of the fuel pressure feeding path, and a communication hole bored in the mounting plate and communicating with the fuel pressure feeding path. , and a check valve provided inside the communication hole on the side of the filter element.