KR20170001061A

KR20170001061A - Oil pump having half magnet type BLDC motor

Info

Publication number: KR20170001061A
Application number: KR1020150090452A
Authority: KR
Inventors: 김보경; 송명준; 전완재; 민경진; 이상률; 니구치 노보루; 심요섭
Original assignee: (주)모토닉
Priority date: 2015-06-25
Filing date: 2015-06-25
Publication date: 2017-01-04

Abstract

The present invention relates to an oil pump for transferring fluid by power of an N-pole motor, comprising: a BLDC motor (10) having magnets (15), wherein the number of magnets is less than N; a pump (20) coupled to a shaft of the BLDC motor (10); and a controller (30) accommodated in a space separated on an identical housing (31) as the BLDC motor (10). Accordingly, by mounting a half-magnet type BLDC motor on a fuel supply pump of a vehicle, weakening of durability due to vibration is prevented while maintaining system stability for a long period of time.

Description

[0001] The present invention relates to an oil pump having a half-magnet type BLDC motor,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil pump equipped with a BLDC motor, and more particularly to an oil pump equipped with a half-magnet type BLDC motor used for fluid transportation including a fuel supply system of a vehicle.

Generally, BLDC motors (Brushless DC Motor) are adopted for fuel pumps of vehicles to ensure high efficiency, long service life and reliability. A BLDC motor includes a stator for generating a magnetic field and a rotor for rotating by a magnetic field generated in the stator.

Referring to FIG. 1, the conventional oil pump is a structure in which the BLDC motor 1 and the controller 2 are formed as separate bodies and connected to each other by a wire harness 5. Therefore, a resistance is generated by the wire harness 5, which causes a deterioration of the system efficiency. In addition to the cost increase due to the harness 5, the cost of the rare earth magnets required for the BLDC motor 1 also increases.

Korean Prior Art No. 1518431 (Prior Art 1) and Korean Patent Registration No. 0814435 (Prior Art 2) are known as prior art documents related thereto.

The prior art reference 1 is a high voltage BIST motor for driving an oil pump including a yoke cover member covering an upper portion of a yoke in a shape of covering a top surface of a terminal structure. The high voltage BIST motor is formed in a wave structure at the center of a yoke cover body, And a receiving groove portion for receiving a printed circuit board to which an electrical signal is connected. As a result, it is expected that the overheating of the high voltage BI DS motor will be recognized in advance.

The prior art document 2 discloses a BLDC drive motor mounted on a base frame for discharging a flow rate, a BLDC drive motor mounted to transmit a ground output to a pumping member, a controller for transmitting a command signal for operation of the BLDC drive motor, And a feedback control unit for compensating the command signal to be driven at a speed. Accordingly, it is possible to integrate the BLDC driving motor and the feedback control unit, and an additional device is not required.

However, there is a limit to ensure long-term system stability and durability by applying to a BLDC motor mounted on a vehicle in the manner disclosed in the above-mentioned prior patent, in particular, a half-magnet type.

1. Korean Patent Registration No. 1518431 entitled "High Voltage Biel DC Motor for Driving Oil Pumps" (Published on May 5, 2015). 2. Korean Patent Registration No. 0814435 entitled "Quantitative Pump Using BLDC Motor" (Published on Mar. 17, 2008).

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide an oil pump with a half-magnet type BLDC motor mounted on a fuel supply system of a vehicle for preventing system durability due to vibration, .

In order to achieve the above object, the present invention provides an oil pump for transferring fluid by the power of an N-pole motor, the oil pump comprising: a BLDC motor having a number of magnets less than N; A pump coupled to an axis of the BLDC motor; And a controller accommodated in a separate space on the same housing as the BLDC motor.

As a detailed configuration of the present invention, the BLDC motor is characterized by having N / 2 magnets on the rotor.

In a detailed configuration of the present invention, the pump is characterized by performing pumping with a cycloid tooth profile.

As a detailed configuration of the present invention, the board of the controller is connected to the BLDC motor via a bar-shaped electric wire fixed to the housing.

At this time, the bar-shaped electric wire is supported in a receiving space formed in the housing via a support piece having a "?" -Shaped cross section.

INDUSTRIAL APPLICABILITY As described above, according to the present invention, the half-magnet type BLDC motor is mounted on the fuel supply pump of the vehicle, and the durability due to vibration is prevented while maintaining the system stability over a long period of time.

1 is a schematic view showing a conventional on-vehicle oil pump
Fig. 2 is a configuration diagram showing a vehicle-mounted oil pump according to the present invention. Fig.
Fig. 3 is a perspective view of the oil pump according to the present invention,
Fig. 4 is a schematic view showing a front view of the oil pump according to the present invention. Fig.
Fig. 5 is an equivalent circuit diagram showing a conventional oil pump according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The present invention relates to an oil pump for transferring fluid by the power of an N-pole motor. Particularly but not exclusively, an oil pump mounted in a fuel supply system of a vehicle.

According to the present invention, a BLDC motor 10 having a number of magnets 15 smaller than N is used. The BLDC motor 10 includes a stator 11 provided with a plurality of teeth through which coils are wound and a rotor 12 provided with a plurality of magnets 15 corresponding to the stator 11. [ Reducing the quantity of the magnet 15 is intended to contribute to cost reduction by reducing the amount of ND magnet using expensive rare earths.

As a detailed configuration of the present invention, the BLDC motor 10 is characterized in that N / 2 magnets 15 are provided on the rotor 12. 3 illustrates a half magnet structure in which three magnets 15 are mounted on a BLDC motor 10 of a six-pole structure. In this case, the rotor 12 may be arranged such that the N - X - N - X - N - X poles face outward. Here, X is formed by magnetizing the core of the core as a magnetized portion to which the magnet 15 is not mounted. Of course, in the case of arranging six magnets 15 in the figure, the N - S - N - S - N - S poles are alternately turned to the outside.

In the BLDC motor 10, the external ratio of the stator 11 and the rotor 12 is most preferably 100: 50 to 60. However, when the external magnet ratio is 50 to 60%, the weight of the magnet 15 And the manufacturing cost is increased. By applying the half magnet to the BLDC motor 10, the outer diameter of the rotor 12 can be designed to be 50% to 60% of the outer diameter of the stator 11, thereby reducing the manufacturing cost and optimizing the efficiency of the motor.

According to the experiment, when the outer diameter of the stator 11 is 85 mm, the outer diameter of the rotor is 36 mm, and the outer diameter ratio is 100: 42, eight magnets of 10x2.5x45 mm are required, Or the outer diameter ratio is less than 50%, the ratio between the electric field and the magnetic field is not optimized. If the outer diameter of the rotor is increased to 49 mm under the same conditions and the outer diameter ratio is 100: 57, 8 magnets having a size of 13.5 × 2.3 × 45 mm are required, and the total volume of the magnets is rapidly increased to 11,178 km. On the other hand, according to the half-magnet structure using four magnets having a size of 13.5 × 3.5 × 45 mm, the total volume of the magnets is reduced to 8,505 Ω even if the external ratio is maintained at 50~60% according to the same performance (output).

According to the present invention, the pump 20 is coupled to the shaft of the BLDC motor 10. The pump 20 and the BLDC motor 10 are accommodated in the respective housings and connected together on the same axis.

As a detailed configuration of the present invention, the pump 20 is characterized by performing pumping in a cycloid tooth shape. In the case of the cycloid tooth type, it is advantageous for compactness and light weight, and vibration and noise are small, which is advantageous for system stabilization. Particularly, even if the torque ripple is slightly increased in the BLDC motor 10 of the half-magnet structure, a certain portion can be canceled by the cicloid tooth profile.

According to the present invention, the controller 30 is accommodated in a space separated on the same housing 31 as the BLDC motor 10. It is preferable that the BLDC motor 10 is housed in the lower space from the housing 31 and the controller 30 is housed in the upper space. On the upper surface of the housing 31, a cover having a cooling fin for heat radiation of the controller 30 is provided.

The board 34 of the controller 30 is connected to the BLDC motor 10 through a bar-shaped electric wire 36 fixed to the housing 31. In this case, The bar-shaped electric wire 36 is connected to apply the three-phase power source (U, V, W) to the BLDC motor 10 as a structure for preventing oscillation due to resonance. The substrate 34 supports the inverter circuit using the resin material holder. The lower end of the bar-shaped wire 36 is connected to the terminal block of the BLDC motor 10, and the upper end thereof is connected to the terminal block of the substrate 34. [ The bar-shaped electric wire 36 can be configured to have a circular cross section, a plate cross section, or a combination thereof. In any case, it is preferable to add a shielding layer to the surface of the bar-shaped wire 36.

At this time, the bar-shaped electric wire 36 is supported in the receiving stand 32 formed on the housing 31 via the support piece 38 of the "A" -shaped section. The receptacle 32 is a portion formed in the form of a narrow passage on one side of the housing 31. The inside of the accommodating table 32 can be filled with a resin having flexibility. The bar-shaped electric wire 36 is preferably configured to include a bent path rather than a straight line. In this case, a support piece 38 such as a resin material is added to the portion bent into the letter "a ".

On the other hand, the supporting piece 38 is formed of a structure separating the three-phase power source (U, V, W) by using a material having insulation, abrasion resistance, heat resistance and cold resistance. The bar-shaped electric wire 36 and the support piece 38 also function to absorb the tolerance.

Referring to FIG. 5, the BLDC motor 10 has a phase inductance, a coil resistance, and an induced voltage, and the controller 30 has a DC side and an AC side resistance. 5 (a) to 5 (b), when the resistance of the harness 5 is lost due to the integration of the BLDC motor 10 and the controller 30, System efficiency is increased. In FIG. 5, reference numeral 5 'denotes a resistance of a conductor from the power source to the controller 30.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined by the appended claims. It is therefore intended that such variations and modifications fall within the scope of the appended claims.

1: motor 2: controller
5: Harness 10: BLDC motor
11: stator 12: rotor
15: Magnet 20: Pump
30: controller 31: housing
32: receptacle 34: substrate
36: bar type wire 38:

Claims

Claims [1] An oil pump for transferring fluid by power of an N-pole motor, comprising:
A BLDC motor (10) having a number of magnets (15) less than N;
A pump 20 coupled to the shaft of the BLDC motor 10; And
And a controller (30) accommodated in a space separated on the same housing (31) as the BLDC motor (10).

The method according to claim 1,
Wherein the BLDC motor (10) comprises N / 2 magnets (15) on a rotor (12).

The method according to claim 1,
Wherein the pump (20) performs pumping in a cycloid tooth form.

The method according to claim 1,
Wherein the substrate 34 of the controller 30 is connected to the BLDC motor 10 via a bar type electric wire 36 fixed to the housing 31. The oil pump of the half-

The method of claim 4,
Wherein the bar type electric wire is supported in a receiving space formed in the housing via a support piece of a "?" -Shaped cross section.