KR20090024085A - Impeller, fuel pump having the impeller, and fuel supply apparatus having the fuel pump - Google Patents

Abstract

An impeller, a fuel pump having the impeller, and a fuel supply apparatus having the fuel pump are provided to supply fuel steadily at low torque by setting up rearward tilt angle of an inner vane groove at 30~80°. An impeller comprises an inner pump chamber and an outside pump chamber coaxially positioned and a plurality of partitions dividing adjacent inner vane grooves(55). A rear surface is located in a back side of a rotational direction of each inner vane groove. The radius direction inner side of the rear surface rearwards inclines to the radius direction outer side from the radius direction inner side of the rotational direction. A first line connects the radial direction inner end of the rear surface to the radial direction outer end of the rear surface. A second line is extended in a radial direction from the radial direction inner end of the rear surface. Between the first line and the second line, a rearward tilt angle(alpha2) is formed. The rearward tilt angle is satisfied with the relation of 30°<= alpha2 <= 80°.

Description

Impeller, fuel pump with impeller and fuel supply device with fuel pump {IMPELLER, FUEL PUMP HAVING THE IMPELLER, AND FUEL SUPPLY APPARATUS HAVING THE FUEL PUMP}

The present invention relates to an impeller for a fuel pump. Moreover, this invention relates to the fuel pump provided with this impeller. Moreover, this invention relates to the fuel supply unit provided with this fuel pump.

Conventionally known turbine-type fuel pumps are mounted to a vehicle's fuel pump to supply fuel to the vehicle engine under pressure.

This type of fuel pump is mounted in an auxiliary tank provided at the bottom of the fuel tank. In this structure, even when the vehicle is moving or inclined, the liquid level of the fuel in the fuel tank is tilted, or even when the liquid level of the fuel in the fuel tank is reduced by fuel consumption, the fuel is reliably extracted or May be discharged. The auxiliary tank is a fuel container filled with fuel from the fuel tank, so that the fuel container can store fuel at a liquid level independent of the liquid level in the fuel tank.

As a structure for filling fuel in an auxiliary tank, for example, US 5,596,970 discloses a pump chamber of a fuel pump. The pump chamber of the fuel pump is formed coaxially in two rows. In this structure, the outer pump chamber provided on the outer side is used to supply fuel to the vehicle engine under pressure, and the inner pump chamber provided on the inner side is used to fill the auxiliary tank with fuel. Further, JP-A-2007-132196 discloses that the pump efficiency of the fuel pump is improved by specifying the front tilt angle or the rear tilt angle of the rear surface located on the rear side in the rotational direction of the vane groove of the impeller. . The rear tilt angle of the rear surface is formed between a line connecting the radially inner portion of the rear surface with the radially outer portion of the rear surface and a line extending radially from the radially inner end. The front tilt angle of the rear face is between a line connecting the center in the rotational axis direction of the rear face and one end in the rotational axis direction of the rear face, and a line extending in the rotational tangential direction from the center in the rotational axis of the rear face. Is formed.

As in US Pat. No. 5,596,970, when the pump chamber is formed coaxially in two rows, the inner pump chamber is used to fill the auxiliary tank with fuel, and the circumferential speed of the impeller decreases in the inner pump chamber as compared to the outer pump chamber. Thus, the suction negative-pressure is reduced in the inner pump chamber as compared to the outer pump chamber.

Thus, for example, when the fuel residual amount in the fuel tank is reduced so that the fuel liquid level in the fuel tank is reduced compared to the pump mounting position, the fuel in the inner pump chamber is exhausted and the suction negative pressure in the inner pump chamber becomes very low. As a result, fuel cannot be extracted from the fuel tank to the internal pump chamber. Even when fuel can be extracted into the internal pump chamber at low suction negative pressure, the fuel cannot be pumped to the auxiliary tank if no gas (air) is discharged from the internal pump chamber to create a pump effect.

To solve this problem, the vane groove structure disclosed in JP-A-2007-132196 can be used as the vane groove shape of the impeller for the internal pump chamber of US 5,596,970 to improve the pump efficiency. However, in this combination, the fuel pumped to the auxiliary tank is boosted excessively in terms of pressure. This excessive boost in pressure leads to an increase in the drive torque of the fuel pump, resulting in an increase in current consumption.

In view of the above and other problems, it is an object of the present invention to provide a fuel pump impeller configured to stably pump fuel at low torque. Another object of the present invention is to provide a fuel pump having an impeller and configured to steadily pump fuel at low torque. Another object of the present invention is to provide a fuel supply unit having a fuel pump and configured to steadily pump fuel at low torque.

According to one aspect of the invention, an impeller for a fuel pump has an outer pump chamber and an inner pump chamber that are substantially coaxial with each other, the impeller being provided in at least a region corresponding to the inner pump chamber and arranged in a rotational direction, each of which is It includes a plurality of partitions for partitioning the inner vane groove adjacent to each other. The rear face is located on the rear side in the direction of rotation of each inner vane groove. At least the radially inner side of the rear surface is inclined rearward in the rotational direction from the radially inner side to the radially outer side. The first line connects the radially inner end of the rear face and the radially outer end of the rear face. The second line extends radially from the radially inner end of the rear face. The first line and the second line form a rear tilt angle α2 therebetween. The rear tilt angle α2 satisfies the relationship of 30 ° ≦ α2 ≦ 80 °.

According to the present invention, it is possible to provide a fuel pump impeller, a fuel pump and a fuel supply unit configured to stably pump fuel at low torque.

The above and other objects, features and advantages of the present invention will become apparent from the following detailed description with reference to the accompanying drawings.

(First embodiment)

The vehicle fuel supply unit 1 of this embodiment will be described with reference to Figs.

As shown in FIG. 1, the fuel supply unit 1 is accommodated in the fuel tank 10 to supply fuel from the fuel tank 10 to the fuel consuming unit outside the fuel tank 10. In this embodiment, the fuel consumption unit is, for example, a vehicle engine. The fuel supply unit 1 has an auxiliary tank 20 provided below the fuel tank 10 and a fuel pump 30 housed in the auxiliary tank 20.

The fuel tank 10 is for storing fuel. In this embodiment, the fuel is for example gasoline. The auxiliary tank 20 is a fuel container provided under the fuel tank 10, and may store fuel at a liquid level independent of the liquid level of the fuel in the fuel tank 10.

In particular, the auxiliary tank 20 is formed of a resin having a cylindrical or box shape at the bottom. In this embodiment, the auxiliary tank 20 is cylindrical in shape. The through-hole 22 is provided in the lower part (sub tank lower part 21) of the auxiliary tank 20, and the inside of the fuel tank 10 communicates with the inside of the auxiliary tank 20 via the through hole 22. As shown in FIG.

The gap space 23 is formed between the lower part of the fuel tank 10 and the lower part of the auxiliary tank 21. The gap space 23 is formed to be sized to accommodate the intake filter 90 for filtering the fuel flowing to the fuel pump 30 to remove the foreign matter, and communicates with the interior of the fuel tank 10.

In the through hole 22, an internal suction tube 58 communicating with an internal pump chamber 50b of the fuel pump 30 described later is inserted. The inner suction tube 58 extends into the gap gap 23 and is connected with the suction filter 90.

The check valve 58a has an inner suction tube 58 which allows fuel to flow only substantially from the gap gap 23 to the inner pump chamber 50b. The check valve 58a restricts the backflow of fuel flowing from the auxiliary tank 20 to the fuel tank 10 via the internal pump chamber 50b and the internal suction tube 58.

Intake filter 91 is also provided on the upper surface of the lower side of the auxiliary tank in the auxiliary tank 20 to filter the fuel flowing to the fuel pump 30 to remove foreign matter. The intake filter 91 is connected to an outer suction tube 59 which communicates with the outer pump chamber 50a of the fuel pump 30 described later.

The fuel pump 30 is configured to have a motor portion 40, a pump portion 50, a resin cover end 70, and the like. The motor unit 40 is supplied with electric power for rotation. The pump unit 50 is supplied with a rotational driving force for extracting and discharging fuel from the motor unit 40. The resin cover end portion 70 forms a discharge passage that guides the fuel discharged from the pump portion 50 from the inside of the fuel pump 30 to the outside of the fuel tank 10.

First, the motor part 40 is a well-known DC electric motor provided with a brush. In particular, the motor unit is configured such that the rotor 43 is rotatably provided in the radially inner side of the permanent magnet 42 periodically provided along the inner circumferential surface of the cylindrical housing 41. In addition, a current is applied to the coil (not shown) of the armature 43 by the rotation of the armature 43 itself. A brushless motor can be used for the motor portion 40.

The coil of the armature 43 includes a terminal of the connector portion 72 provided on the cover end 70, a brush provided in the cover end 70, and a commutator provided in the armature 43 (all of which are not shown). Power is supplied from an external power source via The cover end 70 is fixed to one end side of the housing 41 by caulking or the like. In more detail, the cover end 70 is fixed to the upper end side of the housing 41 in a mounting state as shown in FIG.

The rotating shaft 44 of the armature 43 is supported by a bearing provided at the center of both the pump portion 50 and the cover end 70. In addition, an end portion of the rotation shaft 44 at the side of the pump portion 50 of the rotation shaft 44 is connected to the impeller 51 of the pump portion 50.

In this structure, when a current for rotating the armature 43 is applied to the motor portion 40, the impeller 51 rotates together with the armature 43, so that the pump portion 50 performs the pump operation. do. Fuel flowing from the pump portion 50 to the fuel chamber 45 in the housing 41 by the pumping of the pump portion 50 passes through the discharge flow path formed in the cylindrical outlet 71 of the cover end 70. Flow out of (10).

The pump portion 50 is configured to have an impeller 51, a pump chamber casing 52, and a pump chamber cover 53. In more detail, the impeller 51 is rotatably received about the axis of rotation 44 in the casing formed by the pump chamber casing 52 and the pump chamber cover 53.

The impeller 51 will be described in detail with reference to FIGS. 3 to 6. 3A shows an overall front view of the impeller 51 observed in the direction of the rotation axis. FIG. 3B shows an enlarged view of the periphery of the impeller 51 of FIG. 3A. 4 shows an inclined cross section with the impeller 51 housed in the casing.

The impeller 51 is a disk-shaped member formed of resin. As shown in Figs. 3A and 3B, the impeller 51 has a plurality of outer vane grooves 54 and inner vane grooves 55 formed to transfer momentum to the fuel. The outer vane groove 54 and the inner vane groove 55 are provided in two rows coaxially in the rotational direction.

In more detail, the ring 51a is provided at the outermost periphery of the impeller 51. The outer vane groove 54 is provided in the radially inner side of the ring 51a. The inner vane groove 55 is provided radially inward of the outer vane groove 54.

First, the outer vane groove 54 will be described. As shown in Figs. 3A, 3B and 4, the outer vane grooves 54 adjacent to each other in the rotational direction are divided into V-shaped partition walls 54a. As shown in Fig. 4, the V-shaped partition wall 54a extends from an approximately center in the rotation axis direction (thickness direction) of the impeller 51 to end surfaces 51b on both sides in the rotation axis direction of the impeller 51. Tilt forward in the direction of rotation. That is, the partition wall 54a is formed substantially in a V shape such that both sides of the end face 51b are inclined forward in the rotational direction in the cylindrical section around the rotational axis.

In each outer vane groove 54, the partition wall projects radially outward from the radially inner side of the outer vane groove 54. The partition wall 54b divides a part of the grooves 54 radially inward in the rotational axis direction. Therefore, in the radially outer side of the partition 54b of the outer vane groove 54, the spaces formed by the end faces 51b of the impeller 51 communicate with each other.

Further, as shown in the enlarged view of the outer vane groove 54 in FIG. 5, in the rear face 54c located on the rear side in the rotational direction of the outer vane groove 54, at least the radially inner side is radially at least. It is inclined rearward in the rotational direction from the inner side to the radially outer side. That is, at the surface located on the front surface in the rotational direction of the partition 54a, at least the radially inner side is inclined rearward in the rotational direction from the radially inner side to the radially outer side.

The rear tilt angle α1 is formed between the line 101 and the line 102. Line 101 connects radially inner end 54d of rear face 54c and radially outer end 54e in a plane perpendicular to the axis of rotation. Line 102 extends from the radially inner end 54d in the radial direction of the impeller 51. The rear tilt angle α1 is in the range of approximately 15 ° ≦ α1 ≦ 30 °.

Next, the inner vane groove 55 will be described. The configuration of the inner vane groove 55 is basically the same as that of the outer vane groove 54. In particular, the inner vane grooves 55 adjacent to each other in the rotational direction are divided into V-shaped partition walls 55a inclined forward in the rotational direction. A portion of each inner vane groove 55 in the radially inner side is divided into partition walls 55b.

Further, as shown in the enlarged view of the inner vane groove 55 in Fig. 6, in the rear face 55c located on the rear side in the rotational direction of the inner vane groove 55, at least the radially inner side is radially at least. It is inclined rearward in the rotation direction from the inner side to the radially outer side. That is, in the surface located on the front side in the rotational direction of the partition 55a, at least the radially inner side is inclined rearward in the rotational direction from the radially inner side to the radially outer side.

The rear tilt angle α2 is formed between the line (first line) 103 and the line (second line) 104. The line 103 connects the radially inner end 55d of the rear face 55c with the radially outer end 55e at the surface orthogonal to the axis of rotation. Line 104 extends from the radially inner end 55d in the radial direction of the impeller 51. The rear tilt angle α2 is in the range of approximately 30 ° ≦ α2 ≦ 80 °.

Referring to FIG. 3, a D-shaped hole 51c is formed in the radially inner side of each inner vane groove 55 of the impeller 51. The D-shaped hole 51c penetrates through both end surfaces 51b of the impeller 51. The D-shaped hole 51c is substantially fitted with the D-shaped portion of the rotation shaft 44 of the motor portion 40.

As shown in Fig. 2, the pump chamber casing 52 and the pump chamber cover 53 are formed of a metal (e.g., aluminum die cast) represented by aluminum, or a resin material having excellent fuel resistance and high strength. . First, the pump chamber casing 52 is formed in a substantially cylindrical shape to accommodate the impeller 51. The recess 52a is formed in the pump chamber casing 52.

The recess 52a has a depth in the rotational axis direction, and the depth is about 5 μm to 50 μm thicker than the thickness of the impeller 51. In this structure, the dimension in the rotational axis direction of the casing formed by the pump chamber cover 53 and the pump chamber casing 52 and the dimension in the rotational axis direction of the impeller 51 are such that a predetermined gap is formed therebetween. Is set.

In addition, the outer pump channel 52b and the inner pump channel 52c are substantially arcuately formed over the range of a predetermined angle in the surface of the recess 52a that faces the impeller 51. The outer pump channel 52b and the inner pump channel 52c allow the flow of fuel as the impeller 51 rotates.

The outer pump channel 52b and the inner pump channel 52c are formed at respective positions according to the arrangement of the outer vane groove 54 and the inner vane groove 55 of the impeller 51. The outlet 52d for the fuel chamber is provided at the rear end in the rotational direction of the external pump channel 52b of the pump chamber casing 52. The outlet 52d communicates with the fuel chamber 45 in the housing 41.

On the other hand, the pump chamber cover 53 is formed in a substantially disk shape and is fixed to the pump chamber casing 52 by caulking or the like. The pump chamber cover 53 is provided at the lower end in the mounting state shown in FIG. 1 and is located on the opposite side of the side on which the cover end 70 of the housing 41 is mounted. The pump chamber cover 53 is located at a predetermined position with respect to the pump chamber casing 52.

As shown in Fig. 2, in terms of facing the impeller 51 of the pump chamber cover 53, the outer pump channel 53b and the inner pump channel 53c are also arcuately over a predetermined angle range. In this structure, the outer pump channel 53b and the inner pump channel 53c allow the flow of fuel along the axis of rotation of the impeller 51. In addition, the outer pump channel 53b and the inner pump channel 53c are formed at positions corresponding to the arrangement of the outer vane groove 54 and the inner vane groove 55 of the impeller 51, respectively.

In the pump chamber cover 53, the outer suction tube 59 and the inner suction tube 58 are integrally formed. Further, the distal end of the outer pump channel 53b in the rotational direction of the impeller 51 communicates with the suction flow path in the outer suction tube 59, and the distal end of the inner pump channel 53c in the rotational direction of the inner pump channel 53c. It communicates with the suction flow path in the inside). In addition, the auxiliary tank discharge port 53d communicating with the auxiliary tank 20 is provided at the rear end in the rotational direction of the internal pump channel 53c.

In this structure, the outer pump chamber 50a is the outer pump channel 52b of the pump chamber casing 52, the outer vane groove 54 of the impeller 51 and the outer pump channel 53b of the pump chamber cover 53. Is formed by Further, the inner pump chamber 50b is formed by the inner pump channel 52c of the pump chamber casing 52, the inner vane groove 55 of the impeller 51 and the inner pump channel 53c of the pump chamber cover 53. Is formed.

Further, in this embodiment, similar to that disclosed in US 5,596,970, the inner pump chamber 50b is used to fill the auxiliary tank 20 with fuel supplied from the fuel tank 10, and the outer pump chamber 50a is It is used to supply fuel under pressure from the auxiliary tank 20 to the fuel consumption unit.

Next, the operation of the fuel supply unit of this embodiment having the above-described configuration will be described. When the vehicle start switch (not shown) is turned on and electric power is supplied from the battery to the fuel pump 30 through the connector 72, the armature 43 of the motor portion 40 rotates. Thereafter, the impeller 51 rotates together with the rotation shaft 44 of the armature 43.

When the impeller 51 rotates, and thus the internal pump chamber 50b performs the pump operation, the fuel in the fuel tank 10 is filled with the gap space 23, the suction filter 90, the internal suction tube 58. , And flows sequentially through the internal pump chamber 50b and the outlet 53d for the auxiliary tank 20, and eventually fills the auxiliary tank 20.

In addition, when the external pump chamber 50a performs the pump operation, the fuel in the auxiliary tank 20 is discharged 52d for the suction filter, the external suction tube 59, the external pump chamber 50a and the fuel chamber 45. Flows sequentially through) and is eventually discharged to the fuel chamber 45. The fuel discharged to the fuel chamber 45 passes through the periphery of the armature 43 while cooling the armature 43, and is discharged from the cylindrical discharge port 71 to the outside of the fuel tank 10.

Here, the operation principle of the fuel pump 30 of this embodiment is demonstrated. Since the operating principle of the outer pump chamber 50a is basically the same as the operating principle of the inner pump chamber 50b, only the operating principle of the outer pump chamber 50a will be described with reference to FIG.

The fuel extracted from the external suction tube 59 to the external pump chamber 50a moves from the external suction tube 59 side to the discharge port 52d side for the fuel chamber 45 in accordance with the rotation of the impeller 51, and the external pump channel ( 52b, 53b). In this flow of fuel, the fuel flows while being guided by the partition wall 54b to cause a swirl flow 300 in which the fuel rotates symmetrically between both sides in the direction of the rotational axis of the impeller 51. .

By creating a swirl flow 300, fuel flows from the outer pump channels 52b, 53b to the respective outer vane grooves 54 and from each of the outer vane grooves 54 to the outer pump channels 52b and 53b. Repeat the flow. As a result, the momentum in the rotational direction is transferred from the outer vane groove 54 to the fuel, so that the pressure of the fuel increases.

In this embodiment, since the rear tilt angle α1 of the outer vane groove 54 is set in the range of about 15 ° ≦ α1 ≦ 30 °, as described above, high pump efficiency as previously disclosed in US Pat. No. 5,596,970. This may be produced by the external pump chamber 50a. On the other hand, since the rear tilt angle α2 of the inner vane groove 55 is set to 30 ° ≦ α2 ≦ 80 °, the suction negative pressure necessary for pumping fuel into the internal pump chamber 50b can be stably generated.

This operation is described in more detail, according to FIG. FIG. 7 is a graph showing the relationship between the rear tilt angle α2 of the inner vane groove 55 and the suction negative pressure. More specifically, the graph shows that the fuel liquid level 400 shown in FIG. 1 is lower than the pump mounting position 401, and the impeller 51 runs at 5000 rpm without load when gas (air) fills the internal pump chamber 50b. When rotating, the measurement result of the suction negative pressure is shown. The pump mounting position 401 corresponds to the lowest surface position of the impeller 51.

As indicated in FIG. 7, when the rear tilt angle α2 is set to 30 ° ≦ α, this can generate a stable suction negative pressure necessary for pumping fuel into the internal pump chamber 50b. On the other hand, when the angle α2 is set to α2 <30 °, the auxiliary tank 20 cannot be filled with fuel because the suction negative pressure is small, and the fuel cannot be extracted sufficiently.

When the angle α2 is set to 80 ° <α2, the rear surface of each inner vane groove 55 (compared with the tangent of the inscribed circle 402 formed by the end at the inner diameter side of the inner vane groove shown in Fig. 3B) Since 55c is inclined rearward from the rear in the rotational direction (inner side in the radial direction), the rear surface 55c of the inner vane groove 55 cannot be formed efficiently. Therefore, the rear tilt angle α2 of the inner vane groove 55 is set to 30 ° ≦ α2 ≦ 80 °, so that even when no fuel is present in the internal pump chamber 50b, the fuel is removed from the fuel tank 10. It can be pumped into the auxiliary tank 20.

In addition, the inner pump chamber 50b is provided radially inward as compared with the outer chamber 50a. Thus, in the outer pump chamber 50a, the circumferential speed of the impeller 51 is used to efficiently increase the pressure of the fuel so that the fuel can be supplied under pressure from the auxiliary tank 20 to the outside of the fuel tank 10. have. In addition, in the inner pump chamber 50b, the unnecessary boosting of the fuel pressure can be limited.

As a result, an increase in driving torque in the inner pump chamber 50b is suppressed, and as a result, fuel can be pumped from the fuel tank 10 to the auxiliary tank 20 at a low torque.

(2nd Example)

In the first embodiment, the basic configuration of the inner vane groove 55 is substantially the same as the basic configuration of the outer vane groove 54, and the outer and inner vane grooves 54, 55 are respectively different from each other in the rear tilt angle α1. , α2). In contrast, in the present embodiment, as shown in Figs. 8A and 8B, an example in which the inner vane groove 55x having a different configuration from the outer vane groove 54 in the first embodiment is used will be described.

8A and 8B show views corresponding to Figs. 3A and 3B of the first embodiment, respectively, where Fig. 8A shows an overall front view observed in the rotational axis direction of the impeller 51 in this embodiment, FIG. 8B shows an enlarged view of the periphery of the impeller 51 of FIG. 8A. 8A and 8B, portions substantially similar or identical to those of the first embodiment are denoted by the same reference numerals, respectively. This is substantially the same in the other embodiments described below.

As shown in Figs. 8A and 8B, the partition walls 55b are not provided in each inner vane groove 55x in this embodiment. Thus, the swirl flow 300 described in FIG. 4 is less likely to occur in the internal pump chamber 50b of this embodiment as compared to the structure of the first embodiment. Further, the rear face 55cx of the inner vane groove 55x is inclined rearward in the rotational direction from one end side to the other end in the rotational axis direction.

More specifically, as shown in Fig. 9, the rear surface 55cx is rearward in the rotational direction from the end of the pump chamber cover 53 side to the end of the pump chamber casing 52 side in the cylindrical surface around the rotational axis. Inclined to FIG. 9 is a cylindrical cross sectional view around the axis of rotation along line IX, XI, XVII, XVIII, XIX-IX, XI, XVII, XVIII, XIX of FIG. 8B.

On the cylindrical surface around the axis of rotation, an inclination angle β is formed between the line (third line 105) and the line (fourth line 106). Line 105 connects the end 55fx of the rear face 55cx on the pump chamber cover 53 side and the end 55gx of the rear face 55cx on the pump chamber casing 52 side. The line 106 extends tangentially to the rear side of the rotational direction from the end 55fx on the side of the pump chamber cover 53. The inclination angle β is in the range of 65 ° ≦ β <90 ° in the entire area in the radial direction of the rear face 55cx.

In this embodiment, the inclination angle β is set to be substantially equal in the entire area in the radial direction of the rear face 55cx. Alternatively, one tilt angle β on the cylindrical face at the radially inner peripheral side may be different from the other tilt angle β on the cylindrical face at the radially outer peripheral side. For example, the inclination angle β may be gradually reduced from the inner peripheral side to the outer peripheral side.

The other components are substantially the same as in the first embodiment. Therefore, when the fuel supply unit 1 of this embodiment is operated, the external pump chamber 50a operates in substantially the same manner as the first embodiment.

In addition, in this embodiment, the inclination angle β of the inner vane groove 55x is set to 65 ° ≦ β <90 °. In such a structure, when the fuel surface 400 is lower than the pump mounting position 401 and the gas (air) fills the inner pump chamber 50b, air can be discharged from the inner pump chamber 50b so that the inner pump chamber ( 50b) may produce some pump efficiency.

This operation is described with reference to FIG. FIG. 10 is a graph showing the relationship between the inclination angle β of the inner vane groove 55x and the pumping flow rate of the inner pump chamber 50b. The test conditions are substantially the same as in the case of FIG. As shown in Fig. 10, the inclination angle β is set to 65 ° ≤β <90 °, whereby the pumping flow rate can be sufficiently secured. Thus, the fuel can be sufficiently pumped from the fuel tank 10 to the auxiliary tank 20. On the other hand, when the angle β is set to β <65 °, the pumping flow rate to the internal pump chamber 50b is significantly reduced.

When the inclination angle β is 90 °, the rear surface 55cx is parallel to the rotation axis direction. In this case, the rear face 55cx of the inner vane groove 55x does not incline rearward in the rotational direction from one end side to the other end in the rotational axis direction. Even in this case, as shown in FIG. 10, fuel may be pumped from the fuel tank 10 to the auxiliary tank 20.

According to this embodiment, even when no fuel is present in the inner pump chamber 50b, the fuel can be surely pumped from the fuel tank 10 to the auxiliary tank 20 at low torque.

(Third Embodiment)

In this embodiment, the shape of the V-shaped partition wall 55a of the inner vane groove 55 will be described, whereby the high pump efficiency ηb is generated by the inner pump chamber 50b as compared with the first embodiment. Explain.

In particular, as shown in Fig. 11, the front tilt angle γ is formed between the line (ninth line, 107) and the line (tenth line, 108). Line 107 connects the rotational axis center 55h of the rear surface 55c on the cylindrical surface around the rotational axis with one end 55i in the rotational axis direction of the rear surface 55c. The line 108 extends tangentially from the center 55h in the rotational axis direction of the rear face 55c to the front side in the rotational direction. The forward tilt angle γ is in the range of 70 ° ≦ γ <90 °. FIG. 11 shows a sectional view corresponding to a cross sectional view along the lines IX, XI, XVII, XVIII, XIX-IX, XI, XVII, XVIII, XIX in FIG. 8B in this embodiment.

The other components are substantially the same as in the first embodiment. Therefore, when the fuel supply unit 1 of this embodiment is operated, the external pump chamber 50b operates similarly in the same way as the first embodiment.

Further, in this embodiment, since the front tilt angle γ of the inner vane groove 55 is set to 70 ° ≦ γ <90 °, the fuel surface 400 is lower than the pump mounting position 401, and the gas ( Even when air) fills the inner pump chamber 50b, the pump efficiency of the inner pump chamber 50b can be stably maintained high.

This operation is described in accordance with FIG. FIG. 12 is a graph showing the relationship between the front tilt angle γ of the inner vane groove 55 and the pump efficiency ηb of the inner pump chamber 50b. The test conditions are substantially the same as in the case of FIG. As shown in Fig. 12, the front tilt angle γ is set in a range of 70 ° ≤ γ <90 °, whereby the pump efficiency can be stably maintained high.

This effect can be produced because the front tilt angle γ is set to 70 ° ≦ γ <90 °, so that fuel is excessively swirled in the internal pump channels 52c, 53c of the internal pump chamber 50b. By not generating a flow, the pressure of the fuel can be transmitted so as not to increase excessively. On the other hand, when the angle γ is set to γ <70 °, excessive swirl flow occurs, leading to a significant decrease in pump efficiency.

The pump efficiency ηb of the internal pump chamber 50b is defined by the following equation F1.

ηb = (P * Q) / (Tb * R) ... (F1)

P denotes the discharge pressure of the internal pump chamber 50b, Q denotes the pumping flow rate of the internal pump chamber 50b, Tb denotes the drive torque of the internal pump chamber 50b, and R denotes the Represents the rotation speed. When the front tilt angle γ is 90 °, the partition wall 55b of the inner vane groove 55 is not V-shaped, and high pump efficiency as shown in FIG. 12 can be produced.

As described above, according to this embodiment, even when no fuel is present in the internal pump chamber 50b, the fuel can be pumped from the fuel tank 10 to the auxiliary tank 20 at a low torque, and at the same time pump efficiency (ηb) is kept high stably.

(4th to 7th Example)

The fourth to seventh embodiments are modifications of the first to third embodiments. That is, the impeller 51 from the line 103 connecting the radially inner end 55d of the rear face 55c and the radially outer end 55e of the rear face 55c and the radially inner end 55d. The rear tilt angle α2 between the radially extending lines 104 is set in a range of 30 ° ≦ α2 ≦ 80 °, similarly to the first to third embodiments. In this embodiment, the shape of the surface formed by the rear surface 55c is actually deformed.

In particular, in the fourth embodiment, as shown in Fig. 13, the inner vane groove 55 is formed as an R-chamfer at the corner of the peripheral shape.

In the fifth embodiment, as shown in Fig. 14, the peripheral shape of the inner vane groove 55 is formed in a straight line in the radially inner side and arcuately in the radially outer side.

In the sixth embodiment, as shown in Fig. 15, the circumferential shape of the inner vane grooves 55 is arcuately formed radially inward, and is formed straight in radially outward.

Further, in the seventh embodiment, as shown in Fig. 16, the peripheral shape of the inner vane groove 55 is formed in a straight line.

13 to 16 are enlarged views showing the inner vane grooves 55 in each of the fourth to seventh embodiments, and the inner vane grooves in each embodiment correspond to the inner vane grooves 55 in FIG. In each of the fifth to seventh embodiments, as shown in Figs. 14 to 16, the radially inner end 55d is formed of the arc and the rear face 55c formed by the inner diameter end of the inner vane groove 55. Corresponds to the intersection between the extensions of the straight portions. Further, the radially outer end 55e corresponds to the intersection between the arc formed by the outer diameter side end of the inner vane groove 55 and the extension line of the straight portion of the rear face 53c.

13 to 16, even if the peripheral shape of the inner vane groove 55 is deformed, the rear tilt angle α2 is set in a range of 30 ° ≦ α2 ≦ 80 °, thereby implementing the first to third implementations. The same advantages as the example can be obtained.

(Eighth to tenth embodiments)

Each of the eighth to tenth embodiments is a modification of the second embodiment. In other words, on the cylindrical surface around the axis of rotation, an inclination angle β is formed between line 105 and line 106. Line 105 connects the end 55fx of the rear face 55cx on the pump chamber cover 53 side and the end 55gx of the rear face 55cx on the pump chamber casing 52 side. Line 106 extends tangentially to the rear side of the rotational direction from the end 55fx on the pump chamber cover 53 side. The inclination angle β is in the range of 65 ° ≦ β <90 °. In this embodiment, the shape of the surface formed by the rear surface 55cx is actually deformed.

In particular, in the eighth embodiment, as shown in Fig. 17, the outer cylindrical end of the rear face 55cx is formed of several straight lines. In the ninth embodiment, as shown in Fig. 18, the pump chamber cover 53 side of the rear surface 55cx is curved. Further, in the tenth embodiment, as shown in Fig. 19, substantially only the rear face 55cx is inclined. 17-19 each show a cross-sectional view corresponding to the cross-sectional view along the lines IX, XI, XVII, XVIII, XIX-IX, XI, XVII, XVIII, XIX of FIG. 8B in each of the present embodiments.

As shown in Figs. 17-19, even when the shape of the outer cylindrical end portion of the rear face 55cx is deformed, the inclination angle β is set to 65 ° ≦ β <90 °, thereby the same as in the second embodiment. Advantages can be obtained.

(Example 11)

This embodiment includes a modification of the second embodiment. In the second embodiment, an example in which the inclination angle β of the rear face 55cx of the inner vane groove 55x is substantially the same in the entire area in the radial direction has been described. On the contrary, in this embodiment, as shown in Figs. 22 to 24, the inclination angle β1 at the radially inner circumferential side of the rear surface 55cx is the inclination angle β2 at the radially outer circumferential side of the rear surface 55cx. An example different from is described.

20 is an enlarged view of the periphery of the impeller 51 of this embodiment, corresponding to FIG. 8B. FIG. 21 is a view of the arrow XXI direction of FIG. 20, that is, the rear face 55cx in the rotational direction. 22, 23 and 24 respectively show a cylindrical cross section along the line XXII-XXII in FIG. 20, a cylindrical cross section along the line XXIII-XXIII in FIG. 20, a cylindrical cross section along the line XXIV-XXIV in FIG. The cross section is observed around the axis of rotation.

In the present embodiment, the rear surface 55cx is formed of a plurality of surfaces crossing each other. In particular, the rear surface 55cx is formed of two surfaces, an inner region surface 551 and an outer region surface 552. As shown in Fig. 21, the inner region surface 551 intersects with the outer region surface 552 at the bent portion 55j extending inclined with respect to the radial direction.

In addition, the inner region surface 551 is formed as a surface parallel to the rotation axis direction. Thus, as shown in Fig. 22, the inclination angle β1 formed between the line (fifth line 105a) and the line (sixth line 106a) is given by β1 = 90 degrees. Here, the line 105a has an end 551f on one end side in the axial direction and an end 551g on the other end side in the axial direction on the circumferential side of the radially innermost side of the rear face 55cx. Connect from The line 106a extends from the end portion 551f on one end side in the axial direction in a direction orthogonal to the rear side in the rotational direction.

On the other hand, the outer region surface 552 is formed as a surface inclined to the rear side in the rotational direction from the bent portion 55j. Further, as shown in Fig. 23, the inclination angle beta 2 formed between the line (seventh line 105b) and the line (eighth line 106b) is given by 55 °? The line 105b connects the end 552f on one end side in the axial direction and the end 552g on the other end side in the axial direction at the radially innermost circumferential side of the rear face 55cx. do. Line 106b extends tangentially from the end 552f on one end side in the axial direction to the rear side in the rotational direction.

In this structure, the inner region surface 551 and the outer region surface 552 cross obliquely to each other at the bent portion 55j, as shown in FIG. Further, the inclination angle β3 formed between the line 105c and the line 10c is given by 55 ° ≦ β3 <90 °. Line 105c has an end portion 553f on one end side in the axial direction and an end portion 553g on the other end side in the axial direction from a radius approximately from the center in the radial direction of the rear surface 55cx. Connect from outside the direction. Line 106c extends in the direction orthogonal to the rear side in the rotational direction from the end 553f on one end side in the axial direction.

The other components are substantially the same as the components of the second embodiment. In the present embodiment, the inclination angle β1 and the inclination angle β2 of the rear surface 55cx are respectively deformed. Also in this structure, the inclination angle β2 is set to 55 ° ≦ β2 <90 °, whereby similar advantages as in the second embodiment can be obtained.

This operation is described with reference to FIG. FIG. 25 is a graph showing the relationship between the inclination angle β 2 of the inner vane groove 55x and the pumping flow rate of the inner pump chamber 50b. The test conditions are substantially the same as in the case of FIG. As indicated in FIG. 25, the inclination angle β2 is set to 55 ° ≦ 2 <90 °, whereby fuel can be sufficiently pumped from the fuel tank 10 to the auxiliary tank 20. When the angle β2 is set to β2 <55 °, the pumping flow rate to the internal pump chamber 50b decreases significantly.

Thus, according to this embodiment, even when no fuel is present in the internal pump chamber 50b, the fuel can be surely pumped from the fuel tank 10 to the auxiliary tank 20 at low torque. Further, the inclination angle β2 can be set in a wide range compared to the inclination angle β of the second embodiment and the eighth to tenth embodiments, and thus the design freedom can be improved.

In the above description, each of the inner region surface 551 and the outer region surface 552 is formed in a plane in this embodiment. Alternatively, at least one of the inner region surface 551 and the outer region surface 552 may be formed as a curved surface. Further, only the outer region surface 552 may be formed to be curved so that the inner region surface 551 and the outer region surface 552 smoothly cross each other.

(Other embodiment)

In this embodiment, the partition wall 55b is provided in the inner vane groove 55 in the first and third embodiments. Alternatively, the partition wall 55b may not be provided as in the second embodiment.

In the first to third embodiments, the outer pump chamber 50a is used to supply fuel under pressure from the auxiliary tank 20 to the outside of the fuel tank 10, and the inner pump chamber 50b is the auxiliary tank 20. Is used to fill the fuel from the fuel tank 10. Alternatively, between the outer vane groove 54 and the inner vane groove 55 when the outer pump chamber 50a is used to fill the auxiliary tank and the inner pump chamber 50b is used to supply fuel under pressure. The shape of is reversed.

The structure of the present embodiment can be combined as appropriate.

The procedure of an embodiment of the present invention is described to include a specific continuous step, and other embodiments including various other continuous steps and / or additional steps not disclosed herein are intended to be within the steps of the present invention.

Various modifications and variations can be made in various ways to the embodiments within the spirit of the invention.

1 is a sectional view showing a fuel supply unit of a first embodiment.

Fig. 2 is an enlarged cross sectional view showing the periphery of the pump portion of the fuel pump of the fuel supply unit of the first embodiment;

3A is an overall front view of the impeller of the first embodiment.

3B is an enlarged view of FIG. 3A.

Fig. 4 is an inclined sectional view showing the pump portion of the fuel pump of the first embodiment.

Fig. 5 is an enlarged view of the outer vane groove of the impeller of the first embodiment.

Fig. 6 is an enlarged view of the inner vane groove of the impeller of the first embodiment.

Fig. 7 is a graph showing the relationship between the rear tilt angle α2 and the suction negative pressure.

8A is an overall front view of the impeller of the second embodiment;

8B is an enlarged view of FIG. 8A.

FIG. 9 is a sectional view along the lines IX, XI, XVII, XVIII, XIX-IX, XI, XVII, XVIII, XIX in FIG. 8B; FIG.

Fig. 10 is a graph showing the relationship between the inclination angle β and the pumping flow rate.

FIG. 11 is a sectional view along the lines IX, XI, XVII, XVIII, XIX-IX, XI, XVII, XVIII, XIX of FIG. 8B in a third embodiment; FIG.

12 is a graph showing the relationship between the front tilt angle γ and the pump efficiency.

Fig. 13 is an enlarged view of the inner vane groove of the impeller of the fourth embodiment.

Fig. 14 is an enlarged view of the inner vane groove of the impeller of the fifth embodiment.

Figure 15 is an enlarged view of the inner vane groove of the impeller of the sixth embodiment.

Figure 16 is an enlarged view of the inner vane groove of the impeller of the seventh embodiment.

FIG. 17 is a sectional view along the lines IX, XI, XVII, XVIII, XIX-IX, XI, XVII, XVIII, XIX of FIG. 8B in the eighth embodiment; FIG.

FIG. 18 is a sectional view along the lines IX, XI, XVII, XVIII, XIX-IX, XI, XVII, XVIII, XIX of FIG. 8B in the ninth embodiment; FIG.

Fig. 19 is a sectional view along the lines IX, XI, XVII, XVIII, XIX-IX, XI, XVII and XIX in Fig. 8B in the tenth embodiment.

20 is an enlarged view of the impeller of the eleventh embodiment.

FIG. 21 is a view taken along arrow XXI in FIG. 20; FIG.

FIG. 22 is a cross sectional view along line XXII-XXII in FIG. 20; FIG.

FIG. 23 is a cross sectional view along line XXIV-XXIV in FIG. 20; FIG.

FIG. 24 is a cross sectional view along line XXIII-XXIII in FIG. 20; FIG.

Fig. 25 is a graph showing the relationship between the inclination angle β2 and the pumping flow rate.

<Explanation of symbols for the main parts of the drawings>

1: fuel supply unit

10: fuel tank

20: auxiliary tank

40: motor unit

45: fuel chamber

50: pump part

50a: external pump chamber

50b: internal pump chamber

51: impeller

54: Outside Vane Home

55: inside vane groove

Claims (11)

An impeller for a fuel pump having an inner pump chamber 50b and an outer pump chamber 50a that are substantially coaxial to each other, The impeller, Is provided in at least a region corresponding to the inner pump chamber 50b and arranged in the rotational direction, each of which includes a plurality of partition walls 55a for dividing the inner vane grooves 55, 55x adjacent to each other, The rear surfaces 55c and 55cx are located on the rear side in the rotational direction of the respective inner vane grooves 55 and 55x, At least the radially inner side of the rear surfaces 55c, 55cx is inclined rearward in the rotational direction from the radially inner side to the radially outer side, The first line 103 connects the radially inner end 55d of the rear surfaces 55c and 55cx and the radially outer end 55e of the rear surfaces 55c and 55cx, The second line 104 extends radially from the radially inner end 55d of the rear surfaces 55c and 55cx, The first line 103 and the second line 104 form a rear tilt angle α2 therebetween, The rear tilt angle α2 is an impeller for a fuel pump that satisfies a relationship of 30 ° ≦ α2 ≦ 80 °. The rear surface 55cx is inclined backward in the rotational direction from one end side in the rotational axial direction to the other end side in the rotational axial direction, The third line 105 connects the end 55fx on one end side of the rear face 55cx and the end 55gx on the other end side of the rear surface 55cx, The fourth line 106 extends tangentially from the end 55fx on the one end side toward the rear side in the rotational direction, The third line 105 and the fourth line 106 form an inclination angle β therebetween, The inclination angle β is a fuel pump impeller that satisfies the relationship of 65 ° ≤ β <90 ° in the entire radial direction of the rear surface (55cx). The impeller for a fuel pump according to claim 2, wherein the inclination angle (beta) is substantially constant throughout the radial direction of the rear face (55cx). The method of claim 1, The rear surface 55c is at least partially inclined rearward in the rotation direction from one end side in the rotational axis direction to the other end in the rotational axis direction, and has a plurality of surfaces 551, 552 intersecting with each other. and, The fifth line 105a connects the end portion 551f at one end side of the radially innermost side of the rear surface 55cx and the end portion 551g at the other end side of the radially innermost side of the rear surface 55cx, The sixth line 106a extends tangentially from the end portion 551f of the rear surface 55cx at one end side of the radially innermost side toward the rear side in the rotational direction, The fifth line 105a and the sixth line 106a form an inclination angle β1 therebetween, The seventh line 105b connects the end 552f at one end side of the radially outermost side of the rear surface 55cx and the end 552g at the other end side of the radially outermost side of the rear surface 55cx, The eighth line 106b extends tangentially from the end 552f of the rear face 55cx on one end side of the radially outermost side toward the rear side in the rotational direction, The seventh line 105b and the eighth line 106b form an inclination angle β2 therebetween, The inclined angle β1 is different from the inclined angle β2. The impeller for a fuel pump according to claim 4, wherein the inclination angle β1 satisfies a relationship of β1 = 90 °. The impeller for a fuel pump according to claim 4, wherein the inclination angle β2 satisfies a relationship of 55 ° ≦ β2 <90 °. The rear surface 55c is inclined substantially forward in the rotational direction from the center 55h in the rotational axial direction to both sides in the rotational axial direction, The ninth line 107 connects the center 55h in the rotational axis direction of the rear surface 55c and the end 55i of one of the ends 55i in the rotational axis direction of the rear surface 55c, The tenth line 108 extends tangentially from the center 55h in the rotational axis direction of the rear surface 55c toward the front side in the rotational direction, The ninth line 107 and the tenth line 108 form a front tilt angle γ therebetween, The front tilt angle (γ) is a fuel pump impeller that satisfies the relationship of 70 ° ≤ γ <90 °. 8. A plurality of dividers according to any one of the preceding claims, provided at least in an area corresponding to the outer pump chamber 50a, arranged in a rotational direction, each of which divides the outer vane grooves 54 adjacent to each other. Further comprises an outer partition 54a of, The outer rear face 54c is located on the rear side in the rotational direction of each outer vane groove 54, At least the radially inner side of the outer rear surface 54 is inclined rearward in the rotational direction from the radially inner side to the radially outer side, The outer first line 101 connects the radially inner end 54d of the outer rear surface 54c and the radially outer end 54e of the outer rear surface 54c, The outer second line 102 extends radially from the radially inner end 54d of the outer rear face 54, The outer first line 103 and the outer second line 104 form an outer rear tilt angle α1 therebetween, And the outer rear tilt angle α1 satisfies a relationship of 15 ° ≦ α1 ≦ 30 °. The impeller for a fuel pump according to any one of claims 1 to 7, wherein each inner vane groove (55, 55x) in the radially inner side is partially divided by the partition wall (55b). A fuel pump provided with an impeller (51) for a fuel pump according to any one of claims 1 to 7. A fuel pump according to claim 10, An auxiliary tank 20 provided in the fuel tank 10 for storing fuel, The auxiliary tank 20 is configured to store fuel extracted from the fuel tank 10 at a liquid level independent of the liquid level in the fuel tank, A fuel supply device configured to supply fuel from the fuel tank (10) by pumping the internal pump chamber (50b) of the fuel pump (30).

Images