JPH0447439Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to an in-tank fuel pump used in automobiles and the like.

[Conventional technology]

A conventional example of this type of fuel pump will be explained with reference to FIG. In the figure, 1 is the pump body, which includes a cylindrical yoke 2, a housing base 3, and a housing cover 4.
and a bracket 5. 6 is a magnet fixed inside the pump body 1;
7 and 8 are bearing metals fixed to the bracket 5 and base 3 respectively, 9 are both bearing metals 7 and 8
10 is an armature having an armature core 11, etc., and 11a is a slot. Reference numeral 12 denotes a synthetic resin molded part 12a and a conductive part 12b planted on the outer peripheral side of this molded part 12a.
12c is a groove for insulating the conductive parts 12b, and 13 is a brush. 16 is a suction port provided in the housing cover 4, 17 is a discharge port formed in the bracket 5, and 18 is provided in the housing 19 between the housing base 3 and the housing cover 4 at one end of the shaft 9. The impeller is fixed to prevent rotation by a provided keyway or locking image 20. 21 is a lead wire for electricity supply.

Next, the operation of the above configuration will be explained. When power is supplied from an external power source to the brush 13 via the current-carrying lead wire 21, the armature shaft 9 rotates and drives the impeller 18 to rotate. As the impeller 18 rotates, fuel in the fuel tank is sucked into the housing 19 through the suction port 16 . The fuel sucked into the housing 19 is transferred to the impeller 18
The gas is pressurized and discharged from the discharge port 17, and is supplied to a carburetor (not shown).

However, in the conventional fuel pump described above, since the impeller 18 is fixed to the armature shaft 9, it is difficult to align the rotation center of the impeller 18 with the axis of the armature shaft 9, and the impeller 18 tends to be eccentric. Further, the locking surface 20 is likely to be rubbed by the rotational torque of the armature shaft 9, and the transmission efficiency of the rotation of the armature shaft 9 to the impeller 18 is also poor.

Therefore, as another conventional example, for example, as disclosed in Fig. 2 of Publication No. 57-95467, a commutator and a joint are each fixed to the drive shaft, and the protrusions on both sides of the joint are are fitted into the commutator and runner fan respectively, thereby eliminating friction on the driven part of the impeller.
A device is known that efficiently rotates the impeller in a proper posture.

However, in the above-mentioned other conventional examples, a joint is required separately, and the increase in the number of parts has the disadvantage that the structure of the pump becomes complicated.

Furthermore, the following drawbacks are common to the above two conventional examples. In other words, when fixing the commutator 12 to the armature shaft 9 at a predetermined position, it is necessary to align the circumferential position of the armature core 11 with the conductive part 12b implanted on the outer peripheral side of the molded part 12a. be. This positioning and fixing is performed using the slot 11a of the armature core 11, which is press-fitted into the armature shaft 9 when the armature 10 is assembled, and the conductive portion 12b.
The commutator 12 must be press-fitted while the circumferential position of the commutator 12 is aligned in advance, which is an extremely difficult task.

More specifically, there are thin grooves 12 in the axial direction between the conductive parts 12b planted on the outer circumferential side of the mold part 12a for insulating each conductive part 12b.
c is provided, and the guide for fixing the commutator is press-fitted into this groove 12c while being inserted. Therefore, there was a high risk that the conductive portion 12b or the guide portion of the press-fitting tool would be damaged.

During the above-mentioned positioning work, there is a risk that dirt from hands or the like may adhere to the contact portion of the brush 13 of the commutator 12.

[The problem that the idea aims to solve]

This idea was made in order to solve the common problems in the above conventional examples, and when the commutator 12 is press-fitted into the armature shaft 9 during assembly of the armature 10, the slot 11a of the armature core 11 and the commutator 12 conductive parts 12b can be easily aligned in the circumferential direction, and the armature shaft 9 can be easily aligned with a simple structure.
It is an object of the present invention to provide a highly reliable in-tank fuel pump that can smoothly and efficiently transmit rotation torque of the present invention to an impeller 18.

[Means for solving problems]

The in-tank fuel pump according to this invention includes an armature shaft rotatably supported within the pump body, and a conductive part implanted on the outer circumference of a synthetic resin molded part fixed to one end of the armature shaft. a center hole that freely passes through one end of the armature shaft; and a recess larger than the outer circumference of the rectifying hole at both ends of the center hole;
and an impeller having a pair of holes arranged symmetrically about the center hole in the recess, and an impeller integrally formed with the mold part on the impeller-facing surface of the commutator and arranged in each hole of the impeller. A pair of boss portions are fitted into each other to enable alignment of the armature core of the armature and the commutator in the circumferential direction. It is configured so that the signal is transmitted to the impeller via the

[Effect]

According to this invention, when fixing the position of the conductive part of the commutator at a predetermined position with respect to the slot of the armature core, the boss part is used as a guide part for positioning the conductive part of the commutator in the circumferential direction. This makes it easier to assemble the armature.

In addition, the center hole of the impeller is allowed to pass freely through the armature shaft, and the commutator is integrally formed with a driving boss, which is fitted into the hole in the impeller. Rotational torque can be transmitted smoothly and efficiently to the impeller with a small number of parts.

[Example of idea]

An embodiment of this invention will be described below with reference to the drawings.

FIG. 2 shows an example of an in-tank fuel pump according to this invention, and the same parts as in FIG.

In the figure, 101 is an impeller, and 102 is a commutator consisting of a conductive part 103 and a synthetic resin molded part 104. The molded portion 104 is fixed to the armature shaft 9 by press fitting. As shown in FIGS. 3A and 3B, the impeller 101 includes a center hole 105 that freely passes through the lower end 9a of the armature shaft 9, and recesses 108 larger than the outer circumference of the commutator at both ends of the center hole 105. 108 is formed, and a pair of holes 106, 106 are arranged symmetrically about the center hole 105 in this recess.

On the other hand, on the lower surface of the commutator 102, that is, the surface facing the impeller 101, as shown in FIGS. Both boss portions 107, 107 are fitted into the holes 106, 106, respectively.

When power is supplied to the brush 13 via the energizing lead wire 21, the armature shaft 9 rotates. When the armature shaft 9 rotates, that is, the commutator 102 rotates, the impeller 101 rotates because the boss portion 107 and the hole portion 106 are fitted. The fuel suction and discharge operations by rotation of the impeller 101 are the same as in the conventional case.

Here, since the boss part 107 of the commutator 102 is fitted into the hole part 106 of the impeller 101, the rotational torque of the armature shaft 9 can be transferred to the commutator 10 without using a joint like the conventional one.
2 to the impeller 101 smoothly and efficiently. This allows the number of parts to be reduced and the structure of the pump to be simplified.

Moreover, the center hole 1 provided in the impeller 101
Since recesses 108 larger than the outer circumference of the commutator 102 are formed at both ends of the commutator 102, the molded part 10 of the commutator
A pair of driving boss portions 107 integrally formed with 4,
Since the axial length of 107 can be shortened by at least the length corresponding to the depth of the recess, the forming work is easy and high dimensional accuracy can be obtained, and the mechanical strength of the driving boss is increased, which improves the rectification. The child and impeller can be firmly connected, further improving transmission efficiency.

Further, when press-fitting and fixing the commutator 102 to the armature shaft 9, it is necessary to align the commutator 102 in the circumferential direction with respect to the armature core 11 in advance. During this work, the commutator 102 can be aligned in the circumferential direction with respect to the armature core 11 using the boss portion 107 as a positioning guide, thereby facilitating the work.

For example, the armature core 11 is fixed using the slot 11a on the outer periphery of the armature core 11 press-fitted into the armature shaft 9 as a guide, and the commutator 1
02 is inserted and fixed into the recess of the tool using the boss portion 107 as a guide, and when the commutator 102 is press-fitted into the armature shaft 9 in this aligned state, assembly work can be easily and stably performed. It can be done.

Moreover, the commutator 102 is connected to the armature shaft 9.
By grasping the boss portion 107 when fixing the commutator 102 to the commutator 102, it is possible to prevent dirt from hands or the like from adhering to the contact portion of the commutator 102 with the brush.

Further, the impeller 101 is connected to the armature shaft 9
Since it is set in a free state with respect to the armature shaft 9, it is not forced to tilt toward the armature shaft 9 side as in the conventional case, and is driven to rotate in an appropriate horizontal posture. Furthermore, since the impeller 101 is driven by the bosses 107, 107 on the commutator 102 side that fit into the holes 106, 106 around the center hole 105, compared to the case where the impeller 101 is driven at the center. Therefore, the transmission efficiency from the commutator 102 side is increased, and the torque at the time of starting etc. is also alleviated, so that the impeller 101 side does not wear out.

Note that the boss portions 107, 107 and the hole portion 10
The numbers 6, 106, etc. are not limited to those in the above embodiment, and can be changed as appropriate.

[Effect of idea]

As described above, according to this invention, by using the boss part as a guide part for positioning the commutator, when fixing the commutator to the armature shaft, the armature core and the conductive part of the commutator are aligned in the outer circumferential direction. The work of aligning and fixing becomes easier, improving work efficiency. Moreover, since the commutator can be prevented from becoming dirty, a highly reliable in-tank fuel pump can be obtained.

In addition, the rotational torque of the armature shaft can be smoothly and efficiently transmitted to the impeller with a small number of parts, and the structure of the pump can be significantly simplified. In addition, the pair of driving bosses integrally formed in the molded portion of the commutator are easy to mold, limiting high dimensional accuracy, and the mechanical strength of the bosses is high, making it possible to firmly connect the commutator and impeller. transmission efficiency can be further improved.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the configuration of a conventional in-tank fuel pump, FIG. 2 is a sectional view showing an example of the in-tank fuel pump according to this invention, FIG. 3A is a top view showing the impeller, and FIG. Figure 3 B is B in Figure A
-B sectional view, Figure 4A is a bottom view showing the commutator,
FIG. 4B is a sectional view taken along the line BB in FIG. 4A. 1 is a pump body, 9 is an armature shaft, 11 is an armature core, 11a is a slot, 101 is an impeller, 102 is a commutator, 103 is a conductive part, 104
105 is a synthetic resin molded part, 105 is a center hole, and 106 is a synthetic resin molded part.
107 is a hole, 107 is a boss, and 108 is a recess.
Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] an armature shaft rotatably supported within a pump body; a commutator comprising a synthetic resin molded part fixed to one end of the armature shaft; and a conductive part implanted on the outer circumferential side of the molded part; , a center hole that freely passes through one end of the armature shaft, and a recess larger than the outer circumference of the commutator at both ends of the center hole, and the recesses are arranged symmetrically about the center hole. an impeller having a pair of holes formed in the impeller; and an impeller having a pair of holes formed integrally with the mold part on a surface facing the impeller of the commutator and fitted into each hole of the impeller, and an armature core of the armature and the commutator. and a pair of boss portions that can be aligned in the circumferential direction of the in-tank fuel pump, and is configured to transmit rotational torque of the armature shaft to the impeller via the boss portion of the commutator.