JPH01313668A - Fuel pump - Google Patents

Abstract

PURPOSE:To prevent an impeller from wearing and its efficiency from deteriorating by providing a seal means between a rotary sleeve and a sleeve clearance hole or forming a relief groove reaching a pump chamber from a recessed part. CONSTITUTION:A seal device 71 is provided between a rotary sleeve 31 and a pump housing 22. The seal device 71 secures its lip part so as to be adapted to the peripheral surface of the rotary sleeve 31 to an annular groove 221 formed along a sleeve clearance hole 22B of the pump housing 22. Fuel, allowed to flow into a fuel pump 11, is prevented from being allowed to again flow in recessed parts 22A, 23A of the pump housing 22 and a pump cover 23. Or relief grooves 22G, 23G are formed in the pump housing 22 and the pump cover 23, and most of the inflow of fuel into the recessed parts 22A, 23A is guided to a pump chamber 10 passing through the relief grooves 22G, 23G by rotating an impeller 9.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a fuel pump, and in particular, an impeller is attached to a sleeve rotatably attached around a fixed shaft, and the sleeve is rotated. The present invention relates to a fixed-shaft Wesco type fuel pump that provides energy to fluid, and is capable of preventing a decrease in efficiency by preventing impeller wear.

(Prior Art) Fig. 7 is a vertical cross-sectional view of a conventional fixed-shaft type Wesco fuel pump disposed in the fuel passage of an internal combustion engine, and Fig.
9 is a plan view of the impeller 9, FIG. 10 is a view of the pump housing 22 in FIG. 7 viewed from the direction of arrow A, and FIG. 11 is a view of the pump cover 2 in FIG. 7.
3 viewed from the direction opposite to the arrow A direction. In each figure, the same reference numerals refer to the same or equivalent parts.

First, in Fig. 7.8, the rotating sleeve 31 has a core 4.
is fixed, and a coil 5 is wound and attached to the core 4. The insulation between the core 4 and the coil 5 is
Powder baking is done by painting. Then, sleeves 2OA and 20B are attached to the rotating sleeve 31.
After the coil 5 is press-fitted, a resin mold 5A is applied to the coil 5. The sleeves 20A and 2 (IB) are arranged so that the coil 5 is stably supported.

A commutator 6 is further attached to one end of the rotating sleeve 31.

A portion of the other end of the rotating sleeve 31 is cut so that its cross-sectional outer circumferential shape becomes a split circle, and a sleeve escape hole 22 is formed in the center of the pump housing 22.
After B is inserted, the impeller 9 is attached to the other end. The sleeve escape hole 22B is set larger than the outer diameter of the rotary sleeve 31 so that the rotary sleeve 31 can rotate smoothly.

This impeller 9 is made of resin, for example, and is made of resin.
As shown in FIG. 9, a plurality of holes 9A are formed on the outer periphery, and a hole 9C having approximately the same cross-sectional shape (split circle shape) as the other end of the rotary sleeve 31 is formed in the center thereof. By inserting the hole 9C into the other end of the rotating sleeve 31, the impeller 9 is inserted into the rotating sleeve 31.
mounted on.

This rotating sleeve 31 is rotatably attached to the main shaft 1 using bearings 2 and 3. Moreover, this main shaft 1 is
As shown in FIG. 7, the hole 23B of the pump cover 23
and is fixed to the base 32.

When fixing the pump cover 23 and the main shaft 1, the washer 21 is placed between the rotating sleeve 31 and the pump cover 23. This washer 21 fulfills the function of a thrust bearing for the rotating sleeve 31.

Note that 7.8 and 24 are a brush, a magnet, and a terminal, respectively.

As shown in FIGS. 8 and 11, the pump cover 23 has a recess 23A and an impeller accommodating portion 23 in the center thereof.
E, and a C-shaped groove 23C is formed on its outer periphery. One end of the C-shaped groove 23C is connected to the intake port 13 of the fuel pump.

Further, as shown in FIGS. 8-10, the pump housing 22 is formed with a recess 22A at its center and a C-shaped groove 22C at its outer periphery. Said C-shaped groove 22
A guide port 22D that communicates with the fuel pump interior 11 (FIGS. 7 and 8) is formed at the end opposite to the end corresponding to the suction port 13 of C (see FIG. 10).

The C-shaped grooves 22C and 23C of the pump housing 22 and the pump cover 23 (pump body) are connected to the pump chamber 10 (
7 and 8), and the groove 9A of the impeller 9 projects into the pump chamber 10.

Here, in order to increase the efficiency of the fuel pump, the impeller 9, the pump housing 22 and the pump cover 23 are
It is necessary to set the gap between the contact surface (sliding surface) and the contact surface small. Therefore, the contact portions between the impeller 9, the pump housing 22, and the pump cover 23 are formed with high precision.

Now, returning to Fig. 7, supply power from terminal 24, energize the armature of the thorn fuel pump, and impeller 9.
When the is rotated in a predetermined direction, fuel is sucked through the suction port 13 (in the direction of arrow A) and flows into the pump chamber 10 and the guide port 22D1 shown in FIG. , and is discharged from the discharge port 14 (in the direction of arrow B).

Such a fuel pump is, for example, disclosed in Japanese Utility Model Publication No. 33-1031.
It is described in Publication No. 3.

(Problems to be Solved by the Invention) As described above, the sleeve escape hole 22B formed in the pump housing 22 is formed with a diameter larger than the outer diameter of the rotating sleeve 31, so that the fuel can be removed from the pump chamber 10. A portion of the fuel that has flowed into the pump interior 11 flows into the recess 22.
A and 23A (FIG. 8). This recess 22A
Due to the rotation of the impeller 9, the fuel that has flowed into the fuel pump 23A passes through a small gap between the impeller 9, the pump housing 22, and the pump cover 23, moves to the pump chamber 10, and returns to the fuel pump interior 11. flows into (reflux).

The fuel flowing into the fuel pump is filtered by a filter device (not shown), but this fuel may contain minute amounts of dust that have passed through the filter device.

However, if such dust is contained in the fuel that has flowed into the recesses 22A and 23A from the fuel pump interior 11, when the fuel moves into the pump chamber 10, the impeller 9, pump housing 22, and Pump cover 23
The sliding surface may wear out.

As a result, the gap between the impeller 9, the pump housing 22, and the pump cover 23 increases, and the efficiency of the fuel pump decreases.

The present invention has been made to solve the above-mentioned problems.

(Means and operations for solving the problems) In order to solve the above problems, the present invention is characterized in that the gap between the rotating sleeve and the pump housing is sealed.

This prevents fuel from moving from the recessed portions of the pump housing and pump cover to the pump chamber, thereby preventing wear on the sliding surfaces between the impeller, the pump housing, and the pump cover.

Conversely, a groove is provided on the surface of the pump housing and/or the pump cover that contacts the impeller so as to reach the pump chamber from the recess 22A and/or the recess 23A, so that the fuel flowing into the recess 22A and 23A can be actively channeled. It is also unique in that it is made to flow out into the pump room.

As a result, even if some of the fuel flows into the recesses 22A and 23A, the amount of fuel that passes through the minute gaps between the impeller, the pump housing, and the pump cover is smaller compared to conventional fuel pumps, and the impeller It is possible to reduce or prevent wear on the sliding surfaces between the pump housing and the pump cover.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a first embodiment of the present invention, and FIG. 2 is an enlarged view of the main part of FIG. 1, which is similar to FIG. 8 described above. In FIGS. 1 and 2, the same reference numerals as in FIGS. 7-8 refer to the same or equivalent parts, so the explanation thereof will be omitted.

As is clear from the comparison between FIGS. 1 and 2 and FIG. 7.8, the first embodiment of the present invention has a sealing device 71 between the rotating sleeve 31 and the pump housing 22. It is.

This sealing device 71 is a sealing member with a lip made of, for example, rubber or a material having rubber-like elasticity. hole 2
It is fixed in an annular groove 221 formed along 2B.

By arranging the seal device 71 in this way, the fuel that has flowed into the fuel pump 11 will not flow into the recesses 22A and 23A of the pump housing 22 and the pump cover 23 again when the impeller 9 rotates.

As a result, the sliding surfaces of the impeller 9, the pump housing 22, and the pump cover 23 do not wear much.

In this embodiment, a bobbin 50 is used instead of the sleeves 2OA and 20B shown in FIG. This bobbin 50 is connected to the sleeves 20A and 2 in FIG.
It includes a cylindrical portion 52 corresponding to 0B, and an insulating plate 51 that insulates between the core 4 and the coil 5 at both ends of the core 4 in the rotational axis direction.

This bobbin 50 is arranged such that the insulating plate 51 is approximately equal to or larger than the contour shape of both ends of the bobbin 50, and the cylindrical portion 52 is located outside the coil 5 to be attached after the bobbin 50 is attached. so that it stands out,
It is made of an insulating material such as resin or ceramic.

After the attachment of the core 4 to the rotary sleeve 31 is completed, the bobbin 50 attaches its cylindrical portion 52 to the rotary sleeve 31.
1, the core 4 is placed on both sides of the core 4. After that, the coil 5 is wound or attached.

With this configuration, it is not necessary to apply powder coating to at least both ends of the core 4 for insulation, but of course, as shown in FIG. 7, instead of using the bobbin 50, the sleeve 20A and 20B may be used.

Now, in the present invention, the configuration of the sealing device is as follows:
It goes without saying that the shape is not limited to that shown in FIG. 2 and may be of any shape. Further, this sealing device may be of a non-contact type (labyrinth).

Various configurations of the sealing means for sealing between the rotary sleeve 31 and the pump housing 22 can be easily imagined by those skilled in the art, and therefore their explanations will be omitted.

FIG. 3 is a longitudinal sectional view of a second embodiment of the invention. Third
In the figure, the same reference numerals as in FIG. 1 refer to the same or equivalent parts.

As is clear from the comparison between FIG. 3 and FIG. It has been established.

By shifting the magnet 8A to the impeller 9 side, the armature of the fuel pump is moved to the impeller 9 side (arrow Z
direction). This bias causes the armature bobbin 50. The washer 81 and the pump housing 22 are brought into close contact with each other, and the space between the rotary sleeve 31 and the sleeve escape hole 22B is sealed as in the first embodiment.

In this case, in order to prevent wear of the pump housing 22 and to ensure good rotation of the armature, the sleeve relief hole 22B of the pump housing 22 is filled with metal,
An annular body for the washer 81 made of ceramic or the like may be attached so that its tip protrudes from the pump housing 22.

Similarly, the cylindrical portion 52 of the bobbin 50 may be formed to protrude from the resin molded portion 5A formed on the outer periphery of the coil 5.

FIG. 4 is an enlarged view of the main part of the third embodiment of the present invention, and is similar to FIG. 2.8. Moreover, FIG. 5.6 is a plan view of the pump housing 22 and the pump cover 23,
Figure 10.11 is similar to Figure 10.11;

In Figs. 4 to 6, the same reference numerals as in Figs. 1 to 3, 10, and 11 represent the same or equivalent parts.

This third embodiment, like the first and second embodiments described above, has a pump housing, a housing 22, and a pump cover 23.
Rather than preventing the fuel from flowing into the recesses 22A and 23A, the fuel that has flowed into the recesses 22A and 23A is prevented from passing through the gap between the impeller 9, the pump housing 22, and the pump cover 23. It actively flows out into the pump chamber 10.

That is, the pump housing 22 and the pump cover 2
3, relief grooves 22G and 23G are formed in the sliding motion with the impeller 9, as shown in FIGS. 4 to 6.
Most of the fuel that has flowed into the recesses 22A and 23A is guided into the pump chamber 10 through the relief grooves 22G and 23G due to the rotation of the impeller 9.

In this way, most of the fuel that has flowed into the recesses 22A and 23A passes through the relief grooves 22G and 23G and is guided to the pump chamber 10, so even if the fuel contains a small amount of dust, , impeller 9 and pump housing 22
Also, the sliding motion between the pump cover 23 and the pump cover 23 does not wear out much.

Note that this relief groove may be formed only in either one of the pump housing 22 and the pump cover 23.

(Effects of the Invention) As is clear from the above description, according to the present invention, the following effects are achieved.

(1) Since the space between the rotating sleeve of the armature and the sleeve relief hole of the pump housing is sealed, fuel does not flow into the recess 22A and recess 23A of the pump housing and pump cover when the fuel pump is driven. It disappears.

Therefore, fuel does not pass between the impeller, the pump housing, and the pump cover, and abrasion of the sliding surfaces between the impeller, the pump housing, and the pump cover is prevented.

As a result, it is possible to prevent the efficiency of the fuel pump from decreasing.

(2) Furthermore, since an escape groove is formed in at least one of the pump housing and the pump cover so as to reach the pump chamber from the recess 22A and/or recess 23A formed in the center thereof, when the fuel pump is driven, The fuel flowing into the recess 22A and the recess 23A is actively discharged into the pump chamber without passing much between the impeller, the pump housing, and the pump cover.

Therefore, wear of the sliding surfaces between the impeller, the pump housing, and the pump cover is prevented.

As a result, it is possible to prevent the efficiency of the fuel pump from decreasing.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a first embodiment of the invention. FIG. 2 is an enlarged view of the main part of FIG. 1. FIG. 3 is a longitudinal sectional view of a second embodiment of the invention. FIG. 4 is an enlarged view of main parts of a third embodiment of the present invention. FIG. 5 is a plan view of a pump housing applied to a third embodiment of the present invention. FIG. 6 is a plan view of a pump cover applied to a third embodiment of the present invention. FIG. 7 is a longitudinal cross-sectional view of a conventional fixed shaft type Wesco fuel pump disposed in a fuel passage of an internal combustion engine. FIG. 8 is an enlarged view of the main part of FIG. 7. FIG. 9 is a plan view of the impeller. FIG. 10 is a plan view of a pump 11 housing of a conventional fuel pump. FIG. 11 is a plan view of a pump cover of a conventional fuel pump. 1... Main shaft, 2, 3... Bearing, 8, 8A... Magnet, 9... Impeller, 10... Pump chamber, 22
...Pump housing, 22A...Recess, 22B.
...Sleeve escape hole, 22C...C-shaped groove, 22G...
・Escape groove, 221... Annular groove, 23... Pump cover, 23A... Recess, 23C... C-shaped groove, 23G.
...Escape groove, 31...Rotating sleeve, 71...Sealing device, 81...Washer agent Patent attorney Michito Hiraki and 1 other person Figure 1 Figure 2 Figure 5b and Ohi Figure 3 Figure 4 Figure 7 Figure 8 Figure 9

Claims (2)

[Claims] (1) an impeller having a plurality of grooves on its outer periphery; a rotating sleeve of an armature that rotationally drives the impeller;
A pump body having a pump chamber formed on the outer periphery of the impeller, a recess formed on the inner periphery of the impeller, and a sleeve relief hole larger than the outer diameter of the rotary sleeve for escaping the rotary sleeve. 1. A fuel pump comprising: a sealing means between the rotary sleeve and the sleeve escape hole. (2) an impeller having a plurality of grooves on its outer periphery, and a rotating sleeve of an armature that rotationally drives the impeller;
A pump body having a pump chamber formed on the outer periphery of the impeller, a recess formed on the inner periphery of the impeller, and a sleeve escape hole larger than the outer diameter of the rotary sleeve for escaping the rotary sleeve. 1. A fuel pump comprising: a relief groove extending from the recess to the pump chamber in the pump body.