JPH0244074Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an electric fuel pump used in a vehicle internal combustion engine or the like.

<Prior art> As a conventional fuel pump for an internal combustion engine, for example,
There is something like the one shown in Figure 4.
(See Publication No. 17292).

This is a roller vane type positive displacement pump, which includes a pump housing consisting of a pump head 1, a pump ring 2, and a pump plate 3, and a rotor that rotates around a fixed shaft 4 that is located inside the pump housing and passes through its eccentric position. 5, and a roller 7 housed in a plurality of grooves 6 provided at equal intervals on the outer peripheral surface of the rotor 5. 8 is a suction port, and 9 is a discharge port.

In addition, the armature 1 of the rotor 5 and the motor 10
1 through joints 12 and 13.

<Problems to be solved by the invention> Conventionally, in this type of roller vane fuel pump, the operating noise of the pump increases due to variations in the assembly position accuracy of the pump plate 3 with respect to the pump ring 2. Discharge efficiency and durability sometimes deteriorated.

That is, in the roller vane fuel pump having the above configuration, a pump chamber is formed by the inner circumferential surface of the pump ring 2 and the outer circumferential surface of the rotor 5 interposed therein, and a discharge port provided in the pump plate 3. The larger the overlap area between 9 and 9 in the discharge stroke, the more the fuel discharge resistance can be reduced.
The discharge flow rate of the fuel pump can be increased (discharge efficiency can be improved). Furthermore, since the fuel pump has a higher discharge efficiency when the overlap area is increased in this way, the operating noise of the fuel pump can also be reduced.

However, since the axial movement of the roller 7 housed in the groove 6 provided on the outer peripheral surface of the rotor 5 is restricted by the pump head 1 and the pump plate 3, if the overlap area is made extremely large, , the position of the roller 7 on the pump plate 3 side may be insufficiently regulated at the time of overlapping, and there is a risk that the roller 7 may tilt within the groove 6.

If the roller 7 is tilted in this way, the roller 7 will repeatedly tilt and straighten during fuel pump operation, which will increase the operating noise of the fuel pump and reduce pump efficiency due to poor sealing. Otherwise, the durability of the fuel pump may be significantly reduced.

On the other hand, if the overlap area is made smaller, the inclination of the roller 7 is prevented, but the discharge resistance increases, the discharge flow rate of the fuel pump decreases, and the discharge efficiency of the fuel pump decreases. Furthermore, in this case, the operating noise of the fuel pump increases due to the reduction in discharge efficiency.

As mentioned above, the discharge efficiency, operating noise, and durability of the fuel pump are greatly influenced by the accuracy of the assembly position of the pump plate 3 with respect to the pump ring 2, and it is required to assemble the pump plate 3 in an optimal position.

The present invention was devised in view of these conventional problems. a discharge port;
An object of the present invention is to provide a fuel pump in which the overlap area of the fuel pump can be adjusted easily and with high reliability.

<Means for solving the problem> Therefore, in the present invention, a protrusion is provided on one of the overlapping end surfaces of the pump ring and the pump plate, and the overlap area between the pump chamber and the fuel discharge port is varied on the other side. A groove that can freely engage with the protrusion is provided in at least a predetermined range in the linear direction, and the mounting position of the pump plate relative to the pump ring is adjusted by adjusting the engagement position between the protrusion and the groove.

<Function> With such a configuration, by adjusting the mounting position of the pump plate with respect to the pump ring,
The overlapping area between the pump chamber and the discharge port can be easily adjusted to the optimum position, thereby improving the discharge efficiency and durability while reducing the operating noise of the fuel pump.

<Example> An example of the present invention will be described below based on FIGS. 1 to 3. Incidentally, the same elements as those in the conventional example are given the same reference numerals and the explanation thereof will be omitted.

That is, in the figure, the end surface of the pump plate 3 that overlaps with the pump ring 2 has a center portion C of a maximum diameter arc centered on the shaft 4 of the discharge port 9 opened in the pump plate 3 and the center of the shaft 4. One to two protrusions 21 have a predetermined length in a direction perpendicular to the connecting adjustment direction A and protrude in a sawtooth shape.
Provide one. Note that the adjustment direction A is the overlap area between the pump chamber and the discharge port 9, which is formed by the inner circumferential surface of the pump ring 2 and the outer circumferential surface of the rotor 5 interposed therein, without changing the discharge timing. The direction is to make the change variable.

Also, the pump plate 3 is connected to the pump ring 2.
A bolt through hole 22 for fastening is formed as a long hole in a direction parallel to the adjustment direction A.

On the other hand, in a portion of the end face of the pump ring 2 facing the protrusion 21, a groove 23 is provided which can freely engage with the protrusion 21 within a predetermined range parallel to the adjustment direction A.

With such a configuration, the protrusion 21 and the groove 23 are connected to each other when the pump plate 3 is superposed on the pump ring 2.
By adjusting the engagement position of the pump chamber 14 and the discharge port 9 by gradually shifting linearly,
The overlapping area with the pump plate 3 can be easily fine-tuned to the optimum position where the maximum discharge efficiency can be obtained within a range that prevents the roller 7 from tilting, and the pump plate 3 can be reliably positioned at this position. There will be no positional shift when superimposing and fastening the pump ring 2 onto the pump ring 2.

By such adjustment, it is possible to obtain the maximum ejection efficiency while preventing the roller 7 from tilting, so that operating noise can be reduced and durability can be maintained satisfactorily.

Note that the adjustment direction A is the direction connecting the center of the shaft 4 and the center part C of the maximum diameter arc centered on the shaft 4 of the discharge port 9 opened in the pump plate 3 because of the discharge port in this embodiment. This is to adjust the overlap area without changing the discharge timing using the 9 shapes, and it is clear that the adjustment direction differs depending on the shape of the discharge port 9, etc. Further, an adjustment direction that involves changing the discharge timing may be set.

<Effects of the invention> As explained above, according to the invention, in a roller vane fuel pump, a protrusion is provided on one end surface where the pump ring and the pump plate overlap, and the pump chamber and the fuel discharge port are provided on the other side. A groove is provided that can freely engage with the protrusion within at least a predetermined range in a linear direction that changes the area of overlap with the port, and the mounting position of the pump plate relative to the pump ring is adjusted by adjusting the engagement position between the protrusion and the groove. With this configuration, it is easy to adjust the overlap area between the pump chamber and the discharge port to an optimal value, thereby reducing pump operating noise while improving discharge efficiency and durability. .

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment of the present invention, Fig. 2 is a plan view showing the same embodiment, and Fig. 3 is a
-X arrow sectional view, FIG. 4 is a sectional view showing a conventional fuel pump. 1...Pump head, 2...Pump ring, 3
...Pump plate, 4...Shaft, 5...Rotor, 6...Groove, 8...Suction port, 9...Discharge port, 21...Protrusion, 23...Groove, A...Adjustment direction.

Claims (1)

[Scope of utility model registration request] A pump ring having a cylindrical pump chamber cut out therein is overlaid and fastened between a pump head forming a fuel intake port and a pump plate forming a fuel discharge port, and is inserted through the pump plate to form a pump chamber. a shaft that passes through an eccentric position and has one end fixed to the pump head; a hollow drive shaft that also passes through the pump plate and is fitted into the shaft for free rotation around the axis; A roller vane type fuel pump comprising a disk-shaped rotor fixedly attached to the rotor, and rollers disposed in a plurality of grooves formed on the outer circumferential surface of the rotor, wherein the pump ring and the pump A protrusion is provided on one end surface that overlaps with the plate, and a groove is provided on the other end that freely engages with the protrusion within at least a predetermined range in a linear direction that changes an area of overlap between the pump chamber and the fuel discharge port. A fuel pump characterized in that the mounting position of the pump plate relative to the pump ring is adjusted by adjusting the engagement position between the protrusion and the groove.