| Brushless motor and fluid pump having the same -> Monitor Keywords |
|
|
 
Brushless motor and fluid pump having the sameRelated Patent Categories: Pumps, Motor Driven, Electric Or Magnetic Motor, Rotary Motor And Rotary Nonexpansible Chamber Pump, Submersible TypeBrushless motor and fluid pump having the same description/claimsThe Patent Description & Claims data below is from USPTO Patent Application 20070086905, Brushless motor and fluid pump having the same. Brief Patent Description - Full Patent Description - Patent Application Claims
CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is based on and incorporates herein by reference Japanese Patent Application No. 2005-302698 filed on Oct. 18, 2005. FIELD OF THE INVENTION [0002] The present invention relates to a brushless motor and a fuel pump having the brushless motor. BACKGROUND OF THE INVENTION [0003] For example, according to JP-A-5-340345, a fuel pump includes a brushless motor as a driving source. In general, a motor (brush motor) having a brush causes a loss such as slide resistance between a commutator and a brush, electric resistance between the commutator and the brush, and fluid resistance caused in grooves, via which the commutator is divided into segments. By contrast, a brushless motor may not cause the above losses arising the brush motor. Therefore, a brushless motor is higher than a brush motor in motor efficiency, so that a fuel pump having a brushless motor is enhanced in pump efficiency. Here, the pump efficiency is a ratio of an amount of work produced by the fuel pump relative to electricity supplied to the fuel pump. The amount of work produced by the fuel pump can be calculated by multiplying fuel discharge pressure by a fuel discharge amount. [0004] When the amount of work is constant, as the efficiency of the fuel pump increases, a motor portion can be downsized, so that the fuel pump can be downsized. A fuel pump including a brushless motor may be applied to a small vehicle such as a motor cycle. [0005] A fuel pump may be downsized by reducing a space occupied by coils. In addition, a coil in a fuel pump needs to be protected from corrosion due to exposure to fuel such as debased fuel or low quality fuel is used. [0006] The JP-A-5-340345 does not disclose reduction of the space occupied by the coils in the brushless motor applied to the fuel pump. In addition, in JP-A-5-340345, a case is provided for accommodating the stator, which includes the coils and the stator core, for protecting the stator from corrosion. The components constructing the case are welded for tightly sealing. Accordingly, in this structure manufacturing work is necessary for welding the case. SUMMARY OF THE INVENTION [0007] In view of the foregoing and other problems, it is an object of the present invention to produce a brushless motor that includes coils, which can be protected by a simple structure. It is another object of the present invention to produce a fuel pump having the brushless motor. [0008] According to one aspect of the present invention, a fluid pump includes a stator core that includes a plurality of teeth, which is circumferentially arranged. The fluid pump further includes a plurality of coils each being formed by concentrically winding a wire around an outer circumferential periphery of each of the plurality of teeth. The plurality of coils circumferentially generates magnetic poles in inner circumferential peripheries of the plurality of teeth when being supplied with electricity. The magnetic poles are switched by controlling electricity supplied to the plurality of coils. The fluid pump further includes a rotator that is rotatable around the inner circumferential peripheries of the plurality of teeth, the rotator having an outer circumferential periphery opposed to the inner circumferential peripheries of the plurality of teeth. The outer circumferential periphery defines magnetic poles different from each other with respect to a rotative direction of the rotator. The fluid pump further includes a pump portion that has a rotor member, the rotator rotating the rotor member for pumping fluid. The fluid pump further includes an electrically insulative resin material that is charged between the plurality of teeth, which are circumferentially adjacent to each other. The electrically insulative resin material is molded such that the electrically insulative resin material covers the plurality of coils. [0009] According to another aspect of the present invention, a brushless motor is at least partially submerged in fluid. The brushless motor includes a stator core that includes a plurality of teeth, which is circumferentially arranged. The brushless motor further includes a plurality of coils each being formed by concentrically winding a wire around an outer circumferential periphery of each of the plurality of teeth. The plurality of coils circumferentially generates magnetic poles in inner circumferential peripheries of the plurality of teeth when being supplied with electricity, the magnetic poles being switched by controlling electricity supplied to the plurality of coils. The brushless motor further includes a rotator that is rotatable around the inner circumferential peripheries of the plurality of teeth, the rotator having an outer circumferential periphery opposed to the inner circumferential peripheries of the plurality of teeth. The outer circumferential periphery defines magnetic poles different from each other with respect to a rotative direction of the rotator. The brushless motor further includes an electrically insulative resin material that is charged between the plurality of teeth, which are circumferentially adjacent to each other. The electrically insulative resin material is molded such that the electrically insulative resin material covers the plurality of coils. The electrically insulative resin material substantially insulates the plurality of coils from the fluid. BRIEF DESCRIPTION OF THE DRAWINGS [0010] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description made with reference to the accompanying drawings. In the drawings: [0011] FIG. 1 is a longitudinal partially sectional view showing a fuel pump according to a first embodiment; [0012] FIG. 2 is a sectional view taken along the line II-II in FIG. 1; [0013] FIG. 3 is a perspective view showing a slant restricting member of the fuel pump; [0014] FIG. 4 is a sectional view showing a fuel pump according to a second embodiment; and [0015] FIG. 5 is a sectional view showing a fuel pump according to a third embodiment. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS First Embodiment [0016] As shown in FIG. 1, a fuel pump 10 of this embodiment is an in-tank turbine pump that is provided in a fuel tank of a motorcycle with an engine size of 150 cc, for example. [0017] The fuel pump 10 includes a pump portion 12 and a motor portion 13. The motor portion 13 rotates the pump portion 12. The housing 14 accommodates both the pump portion 12 and the motor portion 13. A pump case 20 and an end cover 48 are fixed by crimping both axial ends of the housing 14. The thickness of a portion of the housing 14 covering the outer circumferential periphery of the stator core 30 in the motor portion 13 is less than the thickness of a portion defining a step 15 in the pump portion 12. The housing 14 is not necessary for defining a magnetic circuit. Therefore, the outer diameter of the motor portion 13 can be reduced by reducing the thickness of the housing 14 surrounding the outer circumferential periphery of the stator core 30. Continue reading about Brushless motor and fluid pump having the same... Full patent description for Brushless motor and fluid pump having the same Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Brushless motor and fluid pump having the same patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Brushless motor and fluid pump having the same or other areas of interest. ### Previous Patent Application: Surface pump assembly Next Patent Application: Gearwheel and method for manufacturing a gearwheel Industry Class: Pumps ### FreshPatents.com Support Thank you for viewing the Brushless motor and fluid pump having the same patent info. IP-related news and info Results in 0.92194 seconds Other interesting Feshpatents.com categories: Electronics: Semiconductor , Audio , Illumination , Connectors , Crypto , 174 |
 * Protect your Inventions * US Patent Office filing 
PATENT INFO |
|
