KR20220087109A - Turbine-type fuel pump - Google Patents

Abstract

To a turbine fuel pump, the casing having an inlet through which fuel is introduced and an outlet through which pressurized fuel is discharged, a pump provided in the casing and pumping and pressurizing the fuel introduced through the inlet, and the pump It includes a motor unit generating a driving force to drive the unit, and the inlet is provided in the upper part of the casing higher than the pump unit so that the inflow direction of the fuel flowing into the pump unit coincides with the gravity direction, and the inlet flows into the pump unit By forming an inlet at the upper end of the casing so that the inflow direction of the used fuel coincides with the direction of gravity, fuel is naturally introduced, thereby improving fuel suction power and increasing the efficiency of the fuel pump.

Description

Turbine fuel pump {TURBINE-TYPE FUEL PUMP}

The present invention relates to a turbine-type fuel pump, and more particularly, to a turbine-type fuel pump for supplying an engine by pressurizing LPG fuel stored in a tank in a liquid state.

In general, Liquefied Petroleum Gas (hereinafter referred to as 'LPG') has a characteristic of being easily liquefied by cooling or pressurization and, conversely, vaporized by heating or reduced pressure. Accordingly, LPG is usually stored in a pressurized (liquefied) state in a high-pressure container, so it is easier to handle than other gases and has a high calorific value.

Conventionally, liquefied gas in a vehicle fueled by LPG was introduced into the engine in a gaseous state together with air to be ignited in the combustion chamber of the engine. There was a problem with lowering.

In order to solve this problem, recently, the LPI (Liquefied Petroleum Injection) engine configured to inject the liquefied gas supplied from the fuel tank to the injector as it is by using the same method as the gasoline engine for the gas stored in the container. was used to increase maneuverability and improve the output part.

For example, the present applicant discloses the LPI system and the fuel pump and fuel pump motor driving technology applied thereto in many of the following Patent Documents 1 to 3, and has applied for and registered a patent.

In general, in the LPI system, a positive displacement pump or a turbine pump is applied to a fuel pump in order to inject liquid fuel as it is from an injector.

In addition, the motor that drives the fuel pump uses a brushless DC motor (hereinafter referred to as 'BLDC motor') to ensure high efficiency, long life and reliability. In particular, a sensorless BLDC motor is used. The motor driver that controls the BLDC motor applied to the fuel pump is installed inside the fuel tank.

The positive displacement pump can easily control the discharge pressure compared to the turbine type pump, but the structure is complicated, and noise is continuously generated when the pump is driven due to the collision between the flange of the pump and the shaft of the motor and the torque ripple during motor control. .

On the other hand, turbine-type pumps have less vibration than positive displacement pumps, so noise is low, continuous water supply is possible, simple structure, easy handling, good movement performance, and the discharge amount changes according to pressure.

The turbine-type pump has a structure in which the fuel introduced through the inlet is pressurized by rotating the impeller and discharged through the outlet.

However, the turbine-type pump according to the prior art has a problem in that the pressure on the inlet side is lowered when the pump is driven, and cavitation occurs inside the pump due to the insufficient amount of fuel introduced through the inlet.

Republic of Korea Patent Registration No. 10-1094882 (Announced on December 15, 2011) Republic of Korea Patent Registration No. 10-1072362 (Announced on October 12, 2011) Republic of Korea Patent Registration No. 10-1021108 (Announced on March 14, 2011)

An object of the present invention is to solve the above problems, and to provide a turbine type fuel pump capable of increasing fuel suction power by smoothly introducing fuel through an inlet of the pump.

Another object of the present invention is to provide a turbine-type fuel pump capable of improving the speed and force at which fuel is introduced through an inlet.

In order to achieve the above object, the turbine-type fuel pump according to the present invention includes a casing in which an inlet through which fuel is introduced and an outlet through which pressurized fuel is discharged is formed, provided inside the casing and introduced through the inlet. A pump unit for pumping and pressurizing fuel and a motor unit generating a driving force to drive the pump unit, wherein the inlet port is higher than the pump unit so that an inflow direction of fuel flowing into the pump unit coincides with a direction of gravity. It is characterized in that it is provided in.

As described above, according to the turbine-type fuel pump according to the present invention, an inlet is formed at the upper portion of the casing so that the inflow direction of fuel flowing into the pump unit coincides with the direction of gravity to naturally introduce fuel, thereby improving fuel suction power, There is an effect that the efficiency of the fuel pump can be increased.

And according to the present invention, a plurality of outer and inner blades are provided in the impeller, and while moving the outer passage, the fuel pressurized by the outer blade is supplied to the inner passage and the inner blade again to compensate to increase the inlet pressure of the pump unit. The effect that it can be achieved is obtained.

So, according to the present invention, by using an impeller having a double-blade structure, the load on the outer blades that send out fuel by increasing pressure is reduced, and the speed and force of fuel inflow can be improved by rapidly delivering the naturally introduced fuel. The effect that can be obtained is obtained.

Accordingly, according to the present invention, it is possible to prevent a decrease in discharge pressure due to a decrease in the inlet side pressure of the fuel pump in advance, and to prevent cavitation due to a shortage of the amount of fuel introduced is obtained.

For this reason, according to the present invention, the efficiency of the turbine type fuel pump and the LPI system can be improved by precisely controlling the discharge pressure to be obtained by driving the fuel pump.

1 is a cross-sectional view of a turbine type fuel pump according to a preferred embodiment of the present invention;
Figure 2 is an exploded perspective view of the pump shown in Figure 1;
3 is a bottom view of the upper cover shown in FIG. 1;
4 is a cross-sectional view of a pump unit applied to a turbine type fuel pump according to another embodiment of the present invention.

Hereinafter, a turbine type fuel pump according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view of a turbine type fuel pump according to a preferred embodiment of the present invention, FIG. 2 is an exploded perspective view of the pump shown in FIG. 1 , and FIG. 3 is a bottom view of the upper cover shown in FIG. 1 .

Hereinafter, terms indicating a direction such as 'left', 'right', 'front', 'rear', 'up' and 'downward' are defined as indicating each direction based on the state shown in each figure. do.

As shown in FIGS. 1 and 2 , the turbine-type fuel pump 10 according to a preferred embodiment of the present invention has a casing in which an inlet 21 through which fuel is introduced and an outlet 22 through which pressurized fuel is discharged are formed. (20), the pump unit 30 provided in the casing 20 and pumping and pressurizing the fuel introduced through the inlet 21, and the motor unit 40 for generating a driving force to drive the pump unit 30 includes

The casing 20 may be formed in a substantially cylindrical shape or a hexahedral shape.

At the upper portion of the casing 20 , an inlet 21 through which fuel stored in a fuel tank (not shown) flows into the casing 20 and an outlet 22 through which fuel pressurized by the pumping operation of the pump unit 30 is discharged. ) may be formed respectively.

In general, in the turbine-type fuel pump according to the prior art, an inlet is provided at the lower end of the casing.

So, in the turbine-type fuel pump according to the prior art, the fuel introduced through the inlet moves in a direction opposite to the direction of gravity, ie, upward, and is supplied to the impeller.

For this reason, in the longitudinal cooling technology, in the turbine-type fuel pump, as the speed and force of the fuel movement decreases while the fuel moves in the opposite direction to the direction of gravity through the inlet, the pressure on the inlet side is lowered, and the fuel is introduced through the inlet. There was a problem that cavitation occurred inside the pump due to the insufficient amount of fuel used.

In order to solve this problem, in the present embodiment, by forming an inlet at the upper portion of the casing, the inflow direction of the fuel flowing into the pump unit may coincide with the gravity direction.

Accordingly, the present invention can increase the efficiency of the fuel pump by naturally introducing fuel along the inflow direction coincident with the gravitational direction to improve fuel suction power.

Here, the inlet 21 and the outlet 22 may be formed at various positions higher than the pump unit 30 , such as the upper end or side of the casing 20 .

A space in which the pump unit 30 and the motor unit 40 are installed may be provided inside the casing 20 .

In addition, the casing 20 has a suction flow path 23 for supplying fuel sucked in through the suction port 21 to the pump unit 30 , and a discharge channel for discharging the fuel pressurized by the pump unit 30 toward the discharge port 22 . Euro 24 can be provided

The motor unit 40 may include a motor that receives power from a controller (not shown) and is driven by a control signal of the controller.

The motor may be provided with various types of motors such as a BLDC motor, a BLAC motor, and a DC motor according to the specifications of the fuel pump 10 .

In FIG. 1 , reference numeral 41 denotes a shaft that transmits the driving force of the motor to the pump unit 30 .

The pump unit 30 is installed in the upper cover 31 and the lower cover 32 and the pressurized space to form a pressurized space for pressurizing the fuel introduced through the inlet 21 therein and delivered from the motor unit 40 . It may include an impeller 33 that rotates by the driving force to pressurize the fuel to a preset pressure.

In this embodiment, the impeller 33 may be provided with a plurality of blades in two stages, respectively, on the outside and the inside. Thus, the impeller 33 may include a plurality of outer blades 331 and inner blades 332 .

The upper cover 31 may have a supply port 311 receiving fuel through the suction passage 23 and an outlet 312 for discharging fuel pressurized by the rotation of the impeller 33 toward the discharge passage.

And, on the bottom surface of the upper cover 31, as shown in FIG. 3, the fuel supplied through the supply port 311 is delivered to the outer and inner blades 331 and 332 provided in the impeller 33. An outer flow path 313 and An inner flow path 314 may be formed.

The outer flow path 313 is formed in a substantially arc shape or a ring shape to correspond to the outer blade 331 , and both ends of the outer flow path 313 may be spaced apart from each other by a preset interval.

The inner flow path 314 is formed in an approximately arc shape or a ring shape to correspond to the plurality of inner blades 332 provided in the impeller 33, and both ends of the inner flow path 314 may be spaced apart by a preset interval. .

Here, one end of the outer passage 313 is connected to the supply port 311 to which fuel is supplied through the inlet 21, and the other end of the outer passage 313 is connected to the inner passage ( 314) may be connected to one end.

In addition, an outlet 312 for discharging fuel pressurized by the inner blade 332 may be provided at the other end of the inner flow path 314 .

Therefore, the fuel supplied to the outer passage through the supply port 321 is pressurized by the rotation of the plurality of outer blades 331 , and is supplied to the inner passage 314 through the transmission passage 315 .

Subsequently, the fuel supplied to the inner flow path 314 is pressurized by the rotation of the plurality of inner blades 332 , and then is discharged toward the discharge port 22 through the discharge port 312 and the discharge flow path 24 .

Meanwhile, a connection flow path 321 connecting the plurality of outer blades 331 and lower ports of the inner blade 332 may be formed on the upper surface of the lower cover 32 .

For example, the connection flow path 321 is formed in an approximately arc shape or a ring shape so as to correspond to the plurality of inner blades 332 provided in the impeller 33 , and both ends of the connection flow path 321 are spaced apart by a preset interval. can be spaced apart.

One end of the connection flow path 321 is disposed at a position corresponding to the connection portion of the transmission flow path 315 and the outer flow path 313 , and the other end of the connection flow path 321 is disposed at a position corresponding to the outlet 312 . can

To this end, at the other end of the connection flow path 321, a transmission unit 322 for blocking additional movement after supplying the fuel supplied to the connection flow path 321 to the inner blade 332 provided in the impeller 33 is provided. can The transfer unit 322 may be formed as an inclined surface inclined toward the upper surface of the lower cover 32 .

As described above, the present invention provides a plurality of outer and inner blades in the impeller, and while moving the outer passage, the fuel pressurized by the outer blade is supplied to the inner passage and the inner blade again to compensate to increase the inlet pressure of the pump unit can do.

Therefore, the present invention uses an impeller having a double blade structure to reduce the load on the outer blades for lifting and sending fuel, and to rapidly deliver the fuel naturally introduced to improve the speed and force of fuel inflow. .

Accordingly, according to the present invention, it is possible to prevent in advance a decrease in discharge pressure due to a decrease in the inlet pressure of the fuel pump and to prevent cavitation due to a shortage of the amount of fuel introduced.

For this reason, the present invention can improve the efficiency of the turbine type fuel pump and the LPI system by precisely controlling the discharge pressure to be obtained by driving the fuel pump.

Next, the coupling relationship and operation method of the turbine type fuel pump according to a preferred embodiment of the present invention will be described in detail.

First, the operator sequentially installs the lower cover 32 , the impeller 33 , and the upper cover 31 in the lower part of the space inside the casing 20 .

At this time, the upper cover 31 may be connected to the inlet 21 through the suction passage 23 to receive fuel stored in the fuel tank.

And the operator installs the motor unit 40 on the upper part of the pump unit 30, and the discharge passage 24 between the discharge port 312 formed in the upper cover 31 and the discharge port 22 formed at the top of the casing 20. to connect the outlet 312 and the outlet 22 .

Accordingly, the fuel moving through the discharge passage 24 when the pump is driven may cool the motor unit 40 through heat exchange with the motor unit 40 .

At this time, in the upper cover 31 , the outer and inner flow paths 313 and 314 and the transmission flow path 315 respectively corresponding to the plurality of outer and inner blades 331 and 332 provided in the impeller 33 are formed.

And the lower cover 32 has a connection flow path 321 corresponding to the plurality of inner blades 332 provided on the impeller 33 is formed.

Through this process, when the assembly of the turbine-type fuel pump 10 is completed, the controller controlling the driving of the fuel pump 10 supplies power to the motor unit 40 through communication with the main control unit provided in the vehicle. and control the driving of the motor unit 40 .

When the motor unit 40 is driven, the fuel stored in the fuel tank is supplied to the pump unit 30 through the inlet 21 and the suction passage 23 provided at the upper portion of the casing 20 .

The fuel supplied to the pump unit 30 is supplied to the impeller 33 through the supply port 311 formed in the upper cover 31 and the outer and inner flow paths 313 and 314, and is preset by rotation of the impeller 33. pressurized by pressure. Then, the pressurized fuel is discharged through the discharge port 312 formed in the upper cover 31 , the discharge passage 24 , and the discharge port 22 formed at the upper end of the casing 20 , and supplied to the engine.

That is, the fuel supplied to the pump unit 30 is supplied to the plurality of outer blades 331 provided in the impeller 33 while moving through the outer flow path 313 formed in the upper cover 31 , and of the impeller 33 . pressed by rotation. At this time, the transfer passage 315 formed in the upper cover 32 transfers the fuel pressurized by the outer blade 331 back to the inner passage 314 while moving the outer passage 313 . Therefore, the fuel supplied to the inner flow path 314 is pressurized by the rotation of the plurality of inner blades 332 provided in the impeller 33 .

In this case, the connection flow path 321 formed in the lower cover 32 may transfer the fuel pressurized by the outer blade 331 to the inner blade 332 again.

As such, the fuel pressurized by the outer and inner blades 331 and 332 is discharged toward the discharge port 22 through the discharge port 312 and the discharge passage 24 of the upper cover 31 .

Through the process as described above, the present invention improves the fuel suction power and increases the efficiency of the fuel pump by forming an inlet at the upper part of the casing so that the inflow direction of the fuel flowing into the pump unit coincides with the direction of gravity to naturally introduce the fuel. can increase

And the present invention provides a plurality of outer and inner blades on the impeller, and while moving the outer passage, the fuel pressurized by the outer blade is supplied back to the inner passage and the inner blade to compensate to increase the inlet pressure of the pump unit. have.

So, the present invention uses an impeller having a double blade structure to increase the fuel pressure and reduce the load on the outer blades that are sent out, and to rapidly deliver the naturally introduced fuel to improve the speed and force of fuel inflow. .

Accordingly, according to the present invention, it is possible to prevent in advance a decrease in discharge pressure due to a decrease in the inlet pressure of the fuel pump and to prevent cavitation due to a shortage of the amount of fuel introduced.

For this reason, the present invention can improve the efficiency of the turbine type fuel pump and the LPI system by precisely controlling the discharge pressure to be obtained by driving the fuel pump.

Meanwhile, in the above embodiment, it has been described that the supply port 311 is connected to one end of the outer passage 313 and the outlet 312 is connected to one end of the inner passage 314 , but the present invention is not necessarily limited thereto. it is not

That is, the present invention connects the supply port 311 with the inner flow path 314 and the discharge port 312 with the outer flow path 313 to sequentially move the fuel in the inner flow path 314 and the outer flow path 313 . It may be changed to pressurize it.

And Figure 4 is a cross-sectional view of the pump applied to the turbine type fuel pump according to another embodiment of the present invention.

The turbine-type fuel pump 10 according to another embodiment of the present invention is similar to the configuration of the turbine-type fuel pump 10 described with reference to FIGS. 1 to 3 above.

However, in this embodiment, the supply port 311 is provided in the central portion of the upper cover 31 where the shaft 41 is installed, as shown in FIG. 4 , and pressurized fuel is provided on one side of the lower cover 32 . An outlet 323 to be discharged may be provided.

In addition, the impeller 33 may be provided in a double structure including a plurality of outer blades 331 and an inner blade 332 installed on the outside of the shaft 41 .

So, the fuel introduced through the inlet 21 formed in the upper part of the casing 20 is supplied to the impeller 33 through the supply port 311, and is pressurized by the rotation of the impeller 33 to the lower cover 32. It is discharged through the formed outlet 323 .

At this time, the inner blade 332 installed on the outside of the shaft 41 primarily pressurizes the fuel supplied to the impeller 33 through the supply port 311 , and the first pressurized fuel is again applied to the outer blade 331 . Second pressurized by

As such, the present invention uses an impeller having a double blade structure to increase the pressure of fuel and reduce the load on the outer blade for sending it out, and to rapidly deliver the naturally introduced fuel to improve the speed and force of fuel inflow. have.

Although the invention made by the present inventors has been described in detail according to the above embodiments, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist of the present invention.

The present invention is applied to a turbine type fuel pump technology that improves the fuel suction power for sucking fuel into the pump unit and increases the efficiency of the fuel pump.

10: turbine type fuel pump
20: casing
21: inlet 22: outlet
23: suction flow path 24: discharge flow path
30: pump unit
31: upper cover 311: supply port
312: outlet 313: outer flow path
314: inner flow path 315: transmission flow path
32: lower cover 321: connection passage
322: delivery unit 323: outlet
33: impeller 331, 332: outer, inner blade
34: discharge port 35: discharge flow path
40: motor 41: shaft

Claims (6)

A casing in which an inlet through which fuel is introduced and an outlet through which pressurized fuel is discharged are formed;
a pump unit provided in the casing and pumping and pressurizing the fuel introduced through the inlet; and
and a motor unit generating a driving force to drive the pump unit,
The inlet port is a turbine type fuel pump, characterized in that provided in the upper portion of the casing higher than the pump unit so that the inflow direction of the fuel flowing into the pump unit coincides with the direction of gravity. According to claim 1,
The pump unit includes an upper cover and a lower cover for forming a pressurizing space therein for pressurizing fuel introduced through an inlet formed in the casing;
and an impeller installed in the pressurized space and rotated by a driving force transmitted from the motor to pressurize fuel to a preset pressure,
The upper cover has a supply port through which the fuel introduced through the inlet is supplied;
Turbine fuel pump, characterized in that the discharge port for discharging the fuel pressurized by the rotation of the impeller toward the discharge port is formed. 3. The method of claim 2,
The upper cover has outer and inner flow paths for supplying fuel to a plurality of outer blades and inner blades provided in two stages to the impeller,
One end of the outer flow path is connected to the supply port,
One end of the inner flow path is connected to the outlet,
The other ends of the outer flow passage and the inner passage are connected to each other through a transmission passage. 4. The method of claim 3,
A connection passage connecting the plurality of outer blades and lower ports of the inner blades is formed in the lower cover,
One end of the connection flow path is disposed at a position corresponding to the connection part of the delivery flow path and the outer flow path,
A turbine type fuel pump, characterized in that a transmission unit for blocking additional movement after supplying the fuel supplied to the connection passage to the inner blade provided in the impeller is provided at the other end of the connection passage. According to claim 1,
The pump unit includes an upper cover and a lower cover for forming a pressurizing space therein for pressurizing fuel introduced through an inlet formed in the casing;
and an impeller installed in the pressurized space and rotated by a driving force transmitted from the motor to pressurize fuel to a preset pressure,
A supply port for supplying fuel introduced through the inlet to the impeller is formed in the center of the upper cover,
A turbine type fuel pump, characterized in that a discharge port for discharging the fuel pressurized by the rotation of the impeller to the discharge port side is formed on one side of the lower cover. 6. The method of claim 5,
The impeller includes a plurality of outer blades and
Turbine-type fuel pump, characterized in that it is provided with a double sphere including an inner blade installed on the outside of the shaft of the motor unit disposed in the supply hole.

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