JPS6135725Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a manual priming pump that is installed in the middle of a fuel path connecting a fuel tank and a fuel injection pump and used to vent air from this fuel path.

A conventional priming pump will be explained based on FIG. 1. A camshaft 2 of a fuel supply pump 1
When the pump piston 4 is given reciprocating motion through the tappet roller 3 due to the rotation of In a fuel supply device configured to be sent to the pump 11, when the fuel supply device is first used,
If air is present in the pipe, the fuel supply pump 1
Since it is not possible to suck in or pump fuel, a priming pump 12 is attached for air venting.

The priming pump 12 includes a cylinder 13 and a plunger 14, and by manually reciprocating a handle portion 15 formed on the plunger 14 from the outside, the pump chamber 16 is expanded and contracted.
Air is removed by sucking and pressurizing fuel into a fuel path 17 connected to the pump chamber 16.

Since the priming pump 12 does not need to be used after the air purge operation is completed, the plunger 14 is fixed at a predetermined position relative to the cylinder 13. Conventionally, the plunger 14 was formed with a male threaded part 18 and the cylinder 13 was formed with a female threaded part 19, and the plunger 14 was fixed by screwing the male threaded part 18 and the female threaded part 19 together.

However, according to the above fixed structure, the male threaded portion 18 and the female threaded portion 19 may collide during reciprocating operation of the plunger 14, which may damage one of the threads and make screwing impossible.
Since the tightening force applied by the operator varies, if the tightening force is small, it will easily loosen due to vibrations, etc. Furthermore, the plunger 14 must be rotated multiple times during the attachment/detachment operation, resulting in poor workability. There was a problem.

The present invention was developed based on these circumstances, and its purpose is to provide a fuel that is easy to operate and that does not cause problems such as failure to fix the plunger and cylinder or undesirable loosening when fixing the plunger and cylinder. It is an object of the present invention to provide a priming pump for a supply device.

That is, in the present invention, the plunger of the priming pump is provided with an elastic member that is biased in the extraction direction at this fixed position and a locking protrusion that extends in the radial direction, and the cylinder has a vertical structure through which the locking protrusion can pass in the axial direction. a groove, an annular groove in which the locking protrusion can rotate at a fixed position continuous with the vertical groove, and a locking recess in which the locking protrusion is locked by receiving the biasing force of the elastic member in the annular groove. It is characterized by the fact that it has been formed.

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3.

The priming pump 30 of this embodiment is attached to the fuel supply pump 1 in place of the conventional priming pump 12 shown in FIG. 1, and 31 is a cylinder. A plunger 32 that is manually reciprocated from the outside is fitted into the cylinder 31 . The plunger 32 has a large-diameter piston portion 33, a rod portion 34, and a handle portion 35 that can be operated from the outside. Pump room 3 in the space
6. This pump chamber 36 is expanded and contracted by the reciprocating movement of the plunger 32. A stepped portion 37 having a smaller diameter than the outer diameter of the piston portion 33 is formed on the tip side of the piston portion 33, and an O-ring 38 is provided in a circumferentially continuous groove in the stepped portion 37.
A sealing material such as the following is inserted. A shaft portion 39 is extended at the tip of the stepped portion 37, and this shaft portion 3
A locking protrusion 40 is attached to the tip of 9. The locking protrusion 40 extends in the radial direction and has an outer diameter larger than the outer diameter of the shaft portion 39.
A plate spring 41 as an elastic member is superimposed on the locking protrusion 40 .

On the other hand, the cylinder 31 has the pump chamber 36
A passage 42 is formed that connects the fuel passage 17 and the fuel passage 17 shown in FIG. A sliding passage 43 is formed on the side of the pump chamber 36 of this passage 42, into which the O-ring 38 slides. Further, a locking flange 44 is formed at the lower end of the sliding passage 43 in the drawing. The locking flange 44 is formed with vertical grooves 45, 45 (only one of which is shown) through which the locking protrusion 40 can pass in the axial direction. and locking flange 4
4, an annular groove 46 is continuous to the vertical groove 45.
is formed. The locking protrusion 40 and the leaf spring 41 can rotate within this annular groove 46. On the upper surface of the annular groove 46 are locking recesses 47, 47 into which the locking protrusion 40 is removably locked.
is provided. Further, the lower surface of the annular groove 46 serves as a bearing surface 48 on which the leaf spring 41 slides, and when the locking protrusion 40 and the leaf spring 41 are positioned within the annular groove 46, the leaf spring 41 abuts on the bearing surface 48. This forces the plunger 32 in the escape direction, that is, upward in the figure, and this urging force presses the locking protrusion 40 into the locking recess 47 to maintain the locked state.

In the embodiment having such a configuration, when it is desired to use the priming pump 30, the handle portion 35 of the plunger 32 is pushed down slightly to disengage the locking protrusion 40 from the locking recess 47, and in this state, the plunger 32 is removed. By rotating the locking projection 40 within a range of 180 degrees, the locking protrusion 40 is opposed to the vertical groove 45 and pulled out from the vertical groove 45. In this way, the plunger 32 is released from the cylinder 31, and the O-ring 38 is released as shown in the right half of FIG.
is separated from the sliding contact passage 43. Therefore, since the pump chamber 36 is in communication with the fuel path 17, when the plunger 32 is reciprocated, fuel is sucked into the fuel path 17 by expansion and contraction of the pump chamber 36, and the fuel path 1
Extrude 7 fuel. At this time, since the O-ring 38 does not come into sliding contact with the inner surface of the cylinder 31 and the sliding contact passage 43, the reciprocating force of the plunger 32 can be reduced.

When the priming pump 30 is not used, the locking projection 40 and the leaf spring 41 are passed through the vertical groove 45 by pushing down the plunger 32 with the locking projection 40 facing the vertical groove 45 . When the locking protrusion 40 and the leaf spring 41 enter the annular groove 46, a pushing force is applied to the plunger 32, causing the plunger 32 to rotate with the leaf spring 41 being bent. When the locking protrusion 40 reaches a position facing the locking recess 47, the pushing force of the plunger 32 is released, and the locking protrusion 40 is locked in the locking recess 47.

Therefore, in this embodiment of the structure, the elastic force of the leaf spring 41 always urges the locking protrusion 40 to engage with the locking recess 47, so that the fixation of the plunger 32 to the cylinder 31 is ensured. ,
There is no risk of loosening even if vibrations are transmitted. In addition, the plunger 32 and the cylinder 31 can be fixed and released within a rotation range of 180 degrees, making the operation extremely easy.

Note that when the plunger 32 is fixed to the cylinder 31, the O-ring 38 comes into close contact with the sliding passage 43 as shown in the left half of FIG. 2, so that communication between the pump chamber 36 and the fuel passage 17 is cut off. It is something.

In the case of the above embodiment, the locking recesses 47, 47 are formed in a shape that is recessed in the upper surface of the annular groove 46, but in the present invention, the locking recess 147 is formed in the flange as shown in FIGS. If the structure is such that it penetrates in the axial direction of 44, the workability will be improved. In this case, the upper surface of the locking protrusion 40 may be formed into a chevron shape, and the chevron-shaped upper surface may be fitted into the lower surface of the locking recess 147 as shown in FIG.

Further, the present invention is not limited to the above embodiments.
For example, other means may be used instead of the leaf spring 41, such as installing a coil spring between the handle portion 35 and the upper surface of the cylinder 31. In other words, when the plunger 32 is fixed, Any material that provides a biasing force may be used.

As detailed above, according to the present invention, since the conventional screw engagement is not used, there is no possibility that the plunger cannot be fixed due to damage to the thread, and the locking protrusion is inserted into the locking recess by the elastic member. Since the locked state is maintained, the fixation will not be undesirably released even if vibrations or the like are transmitted. Moreover, since the plunger only needs to be rotated within a range of 180 degrees when fixing and releasing, the operation is quick and easy.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a conventional swimming pump together with a fuel supply device, Figs. 2 and 3 show an embodiment of the present invention, and Fig. 2 shows a priming pump with the left and right halves in different operating states. A sectional view of the pump, FIG. 3 is an exploded cutaway sectional view of the main parts. Further, FIGS. 4 and 5 show a modification of the present invention, with FIG. 4 being an exploded cutaway sectional view of the main parts, and FIG. 5 being a sectional view showing the locked state of the locking protrusion. 30...Priming pump, 31...Cylinder, 32...Plunger, 36...Pump chamber, 4
0... Locking protrusion, 41... Leaf spring (elastic member),
45... Vertical groove, 46... Annular groove, 47,147...
...Latching recess.

Claims (1)

[Scope of utility model registration request] It is installed in the middle of the fuel path that connects the fuel tank and the fuel injection pump, and consists of a cylinder that forms a pump chamber that communicates with the fuel path, and a manually reciprocated plunger that expands and deflates this pump chamber. In the priming pump, the cylinder and the plunger are fixed at a predetermined position when not in use, and the plunger includes an elastic member that is biased in the extraction direction at the fixed position and a locking protrusion that extends in the radial direction. The cylinder is provided with a vertical groove through which the locking protrusion passes in the axial direction, an annular groove continuous with the vertical groove through which the locking protrusion can rotate at the fixed position of the plunger, and a A priming pump for a fuel supply device, characterized in that a locking protrusion is formed with a locking recess in which the locking protrusion is locked under the biasing force of the elastic member.