JPH0437784Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention has an oil filler port at the upper end, and the lower end is fixed in a fuel supply pipe connected to the fuel tank. To provide a fuel oil backflow prevention valve for an automobile, which allows the fuel oil to flow to a fuel tank without any hindrance, but closes when the automobile overturns or turns while traveling on a curve to prevent fuel oil from leaking outside from an oil filler port.

(Prior Art) Conventionally, a check valve provided in an oil supply pipe has been known, for example, as disclosed in Japanese Utility Model Application Publication No. 59-53122, and in addition, the valves shown in Figs. 4 and 5 are known. It is. It consists of a funnel cylinder part 1 whose diameter is reduced downward, a ventilate or hourglass-shaped cylinder body 3 having a spherical valve seat part 2 connected to its lower end and enlarged downward, and a cylinder body 3 having a valve seat part 2 connected to its lower end and enlarged downward. An integrally molded plastic product consisting of a plurality of legs 5 that hang downward from the lower end and each have an inward protrusion 4 at the lower end, and a ball valve that is buoyant with respect to fuel oil is mounted on the protrusion 4 at the lower end of each leg. 6 is supported at a distance below the valve seat portion 2.

(Problem to be solved by the invention) In general, ball valves are designed to have sufficient buoyancy for the fuel oil, so that when the vehicle overturns or turns, the fuel oil that tries to flow backwards through the oil supply pipe quickly closes the valve seat. A hollow, thin-walled plastic sphere is used to levitate and close the valve.

For this reason, when fuel oil is injected from the oil inlet, the ball valve is strongly pushed downward by the fuel oil flowing down through the funnel, and the inward movement of each leg that locally supports the ball valve from below causes The load is concentrated on the protrusion,
As a result, that part of the ball valve may become recessed and deformed, and when the valve is closed, fuel oil may leak from between the recess and the valve seat and flow toward the oil filler port. In order to prevent this deformation, increasing the wall thickness of the ball valve increases the weight and reduces the buoyancy, resulting in poor valve closing response.

In addition, in order to fix this cylindrical body in the oil supply pipe 7 made of steel pipe, the cylinder body is fitted into the oil suction pipe, and the oil supply pipe is squeezed from around the constricted part of the cylinder body in the shape of a drum. To do so, it is necessary to accurately match the position where the cylinder is inserted into the oil supply pipe and the position where the oil supply pipe is squeezed from the circumference, which is extremely time-consuming.

(Means for solving the problem) Therefore, the present invention encloses the valve seat part in an outer cylinder, and suspends a plurality of struts downward from the lower end of the outer cylinder.
Each of the above-mentioned supports supports a ring that places the ball valve at a distance below the valve seat, and a locking piece that projects outward is provided at the lower end of all or a part of the above-mentioned support, and the lower end of each support. is connected to a flange ring having a larger outer diameter than the outer cylinder.

(Embodiment) In the illustrated embodiment, the same components as in the conventional example described above are given the same reference numerals.

8 is the above-mentioned outer cylinder, 9 is a support column, 10 is a ring,
Reference numeral 11 indicates a locking piece, and reference numeral 12 indicates a collar ring. In this embodiment, these are integrally molded from plastic, and a separately molded cylinder 3 is inserted into the outer cylinder 8 from above, and the furnace cylinder 1 is inserted into the outer cylinder 8 from above.
A protrusion 1' protruding from the outer periphery of the upper half is inserted into a hole 8' provided at the upper end of the outer cylinder to assemble it. Note that the ball valve 6 is placed on the ring 10 before assembly.

In this embodiment, four struts 9 hang down from the lower end of the outer cylinder at equal intervals, and an inward protrusion 13 is provided on the inner surface of each strut at the same level for reinforcement.
0 is connected to the tip of each projecting portion 13.

A wide portion 14 is provided at the lower ends of a pair of opposing columns, and a tongue-shaped locking piece 11 is formed in this portion by a U-shaped notch 11'. Each locking piece 11 has a serrated claw 15 at its lower free end, and there is a gap 16 between the flat lower surface of the claw 15 and the flange ring 12, which is approximately the same as the wall thickness of the oil supply pipe 7. It is maintained.

The lower end of the oil supply pipe 7 is bulged to form an inward annular groove 17 that bulges in a folded manner in the outer circumferential direction.

To fix this check valve in the oil supply pipe, insert it into the pipe from below. As a result, the claws 15 of each locking piece 11 protruding outward from the outer periphery of the outer cylinder 8 are pushed by the lower wall 17' of the annular groove 17, so that each locking piece 11 is bent inward, and the flange ring 12 When the upper surface abuts the lower wall 17' of the annular groove from below, the pawl 15 is located within the annular groove 17, so each locking piece 11 uses its own elasticity to rebound and restore its flexure, causing the pawl 15 to form an annular shape. Groove 1
7 from the inside. Therefore, after that, when pushed upward, the collar ring 12 contacts the lower wall 17' of the annular groove 17 from below, and when pulled downward, the lower surface of the pawl 15 contacts the same lower wall 17' from above, so that it moves in the vertical direction. fixed immovably.

When fuel oil is injected, the ball valve 6 is pushed downward by the fuel oil flowing down from the reactor tube 1, but the ring 10 supports the ball valve 6.
Since the ring supports the ball valve 6 around the entire circumference of the annular upper surface, there is no local concentration of load on the ball valve 6 unlike in the conventional example, and there is no risk of deformation even with a thin ball valve.

In addition, since a ball valve with a thin wall and large buoyancy can be used, the valve closing response is extremely good.
The valve closes before the fuel oil is about to leak, and leakage of fuel oil can be reliably prevented.

In this embodiment, the inner diameter of the oil supply pipe 7 is a little larger than the outer diameter of the outer cylinder 8, so there is an auxiliary tube inside the oil supply pipe 7 at a position surrounding the outer cylinder 8, the inner diameter of which is the same as or slightly larger than the outer diameter of the outer cylinder. Although the pipe 18 is attached by welding, the auxiliary pipe 18 is not necessary if the same annular groove 17 is formed by bulging at the lower end of the oil supply pipe whose inner diameter is the same as or slightly larger than the outer diameter of the outer cylinder.

In addition, this embodiment includes a cylinder body 3, an outer cylinder 8, and a ball valve 6.
It consists of three parts, but if the space between the pillars is widened so that the ball valve 6 can be placed on the ring 10, the cylinder body and the outer cylinder can be molded as one, making it two parts with the ball valve. . Note that the diameter of the funnel tube 1 is reduced downward in order to provide a concave spherical valve seat portion 2 that matches the curvature of the ball valve 6 underneath, and a valve is provided at the upper end of the inner circumference of the outer tube. It is also possible to omit the furnace tube part if the seat part is formed.

Furthermore, a rubber pipe is placed over the lower end of the fuel supply pipe to connect it to the fuel tank, but in this case, the bulge at the bottom end of the fuel supply pipe prevents the band that tightens the rubber pipe from slipping downward from the fuel supply pipe. It serves as a stopper to prevent this.

(Effects of the invention) According to this invention, it can be fixed in the oil supply pipe by simply fitting it into the oil supply pipe from below, so if the lower end of the oil supply pipe is machined with a bulge in advance, there is no need to process the pipe afterwards, making it very easy to fix. It can be performed. The pressure exerted by the injected fuel oil on the ball valve is distributed around the entire circumference of the ring, so even a ball valve with a thin wall will not deform. It is possible to provide a check valve with outstanding performance.

[Brief explanation of the drawing]

Fig. 1 is a front view of one embodiment of the check valve of the present invention, Fig. 2 is a sectional view taken along the - line in Fig. 1, and Fig.
The figure is a vertical sectional side view showing a state in which the direction is changed by 90 degrees from that shown in Fig. 1, and it is fixed in the oil supply pipe. Fig. 4 is a perspective view of a conventional check valve, and Fig. 5 shows the check valve shown in Fig. 4. This is a cross-sectional view showing the state fixed in the oil supply pipe.
1 is a funnel tube, 2 is a valve seat portion, 3 is a cylinder body, 6 is a ball valve, 7 is an oil supply pipe, 8 is an outer cylinder, 9 is a column, 10 is a ring, and 11 is a locking piece.

Claims (1)

[Scope of Claim for Utility Model Registration] A cylindrical body having a downwardly enlarged spherical valve seat is fixed in a fuel supply pipe having a fuel filler port at its upper end and a lower end connected to a fuel tank, and In a fuel oil backflow prevention valve for an automobile, which has a ball valve that is buoyant with respect to the fuel oil arranged below, a plurality of struts are suspended downward from the lower end of the outer cylinder that encloses the cylinder body, and each of the above struts In addition to supporting a ring for placing the ball valve at a distance below the valve seat, a locking piece projecting outward is provided at the lower end of all or some of the pillars, and the lower end of each pillar is connected to the outside of the valve seat. A fuel oil backflow prevention valve for an automobile, characterized in that it is connected to a flange ring having an outer diameter larger than the cylinder.