WO2021199012A1

WO2021199012A1 - Leakage proof electric water pump

Info

Publication number: WO2021199012A1
Application number: PCT/IB2021/052821
Authority: WO
Inventors: Kabir BHANDARI; Amardip KUMAR; Praveen Gupta; Ashok Kumar
Original assignee: Padmini VNA Mechatronics Pvt Ltd
Current assignee: Padmini VNA Mechatronics Pvt Ltd
Priority date: 2020-04-02
Filing date: 2021-04-05
Publication date: 2021-10-07
Anticipated expiration: 2022-10-02

Abstract

The present invention provides a leakage proof electric water pump, comprising of a volute casing (1); a housing (3); a rotor assembly (4); a bush (12); a rotor (5); a rotor casing (6); a shaft (7); a stator assembly (8); a PCB (9); and a cover (11) for covering lower part of pump; wherein the a volute casing (1) is joint with rotor casing (6), the rotor casing (6) is joint with housing (3) and the housing (3) is joint with cover (11) through a clean infrared welding (CIT) technique to form a leakage proof electric pump and increases the life of leakage proof electric pump with high welding strength.

Description

“LEAKAGE PROOF ELECTRIC WATER PUMP”

FIELD OF THE INVENTION

The present invention relates to a leakage proof electric water pump. In a more elaborative way, the present invention is directed towards a leakage proof electrically controlled BLDC motor based electric water pump that is welded with infrared welding (CIT) technique in order to increase durability of the pump for the applications in cabin heating, cooling of engine, inverter and battery in electric/hybrid vehicles.

BACKGROUND OF THE INVENTION

Conventionally, water pumps are driven by a belt attached to the crankshaft of internal combustion engine which takes mechanical power from the engine to circulate coolant through the engine and heater to cool the engine or heat the vehicle's occupant cabin. The rotational speed of internal combustion engine is responsible for determining the amount of refrigerant flowing out of the mechanical water pump. Therefore, in order to operate the heater and the radiator normally, the engine speed must be increased. Thus, on increasing the engine speed the fuel consumption also increases.

At present, in contrast with the mechanical water pump, the large number of vehicles are shifted towards an electric water pump since the electric water pump is capable of determining the amount of refrigerant regardless of the rotational speed of the internal combustion engine. The electric water pump is driven by an electric motor and is controlled by a controlling unit. The electrically driven water pump if employed in the electric /hybrid vehicles, is used for the cooling of its components. During the operation of electric water pump, sometimes a leakage occurs in the joints of various parts of pump if not welded properly and may cause damages to several parts of the water pump and creates negative effect on the efficiency of the pump.

US7956509B2 discloses an electric pump driven by a compact electric motor in which a coil is disposed in a ring form around and along a stator core which has a plurality of claw magnetic poles that extend alternately from both ends of one member of the stator core toward the end of the other member thereof. A stator core can be made from a compressed powder core by molding with resin, with the molded portion able to serve as a partition separating pump and motor units. The disadvantage of cited document is that the different parts of pump are fastened by bolts which may leads to leakage problem and effects the durability of pump.

Therefore, in order to overcome the aforementioned drawback, there exists a need to develop leakage proof and highly durable electric water pump that is welded with clean infrared welding (CIT) technology in order to maintain high welding strength of the electric water pump.

OBJECT OFTHE INVENTION The main object of the present invention is to provide an electrically controlled BLDC motor based electric water pump having applications in cabin heating, low pressure EGR cooling, battery cooling, inverter cooling and alike.

Another object of the present invention is to provide an infrared welding (CIT) on the edges of different components of leakage proof electric water pump with less flash for achieving a leakage proof electric water pump.

Another object of the present invention is to improve the welding strength of the leakage proof electric water pump for increasing the pump life.

Another object of the present invention is to improve the reliability of welding joints.

Still another object of the present invention is to develop a leakage proof electric water pump with enhanced welding that is highly reliable, efficient and cost effective.

SUMMARY OF THE INVENTION

The present invention provides a leakage proof electric water pump by joining the edges of pump components together through an infrared welding (CIT) technique with less flash in order to increase the life of leakage proof electric water pump and welding strength for the applications in cooling of engine, power electronics and battery of electric/hybrid vehicles.

In an embodiment, the present invention provides a leakage proof electric water pump, comprising of a volute casing; a washer; a housing with at least two mounting assembly; a rotor assembly; a cylindrical bush; a rotor; a rotor casing; a shaft inserted in the rotor casing; a stator assembly; a printed circuit board (PCB); a self-tapping screw; and a cover for covering lower part of pump; wherein a volute casing is joined with rotor assembly, the rotor casing is j oined with housing and the housing is joined with cover through a clean infrared welding (CIT) technique to form a leakage proof electric water pump and increases the life of pump with high welding strength.

BRIEF DESCRIPTION OF THE DRAWING

The object of the invention may be understood in more details and more particularly description of the invention briefly summarized above by reference to certain embodiments thereof which are illustrated in the appended drawings, which drawings form a part of this specification. It is to be noted, however, that the appended drawings illustrate preferred embodiments of the invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective equivalent embodiments.

Fig. 1 represents an exploded view of leakage proof electric water pump in accordance with an embodiment of the present invention.

Fig. 2 represents a side view of leakage proof electric water pump in accordance with an embodiment of the present invention.

Fig. 3 represents a cross-sectional view of leakage proof electric water pump in accordance with an embodiment of the present invention.

Fig. 4 shows welded joints of different parts of leakage proof electric water pump in accordance with an embodiment of the present invention.

Fig. 5 shows the welding rib for joining different parts together in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Many aspects of the invention can be better understood with references made to the drawings below. The components in the drawings are not necessarily drawn to scale. Instead, emphasis is placed upon clearly illustrating the components of the present invention. Moreover, like reference numerals designate corresponding parts through the several views in the drawings. Before explaining at least one embodiment of the invention, it is to be understood that the embodiments of the invention are not limited in their application to the details of construction and to the arrangement of the components set forth in the following description or illustrated in the drawings. The embodiments of the invention are capable of being practiced and carried out in various ways. In addition, the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.

The present invention provides a leakage proof electric water pump by joining the edges of pump components together through an infrared welding (CIT) method with less flash in order to increase the life of electric water pump and welding strength for the applications in cooling of engine, power electronics and battery of electric/hybrid vehicles.

In an embodiment referring to Fig. 1 and Fig. 2, the exploded and side view of the leakage proof electric water pump is illustrated. The leakage proof electric water pump comprising of a volute casing 1; a washer 2; a housing 3; a mounting assembly 3(a); a rotor assembly 4; a rotor 5; a rotor casing 6; a shaft 7; a stator assembly 8; a printed circuit board (PCB) 9; a self-tapping screw 10; and a cover 11. The electric water pump further comprises at least two mounting assembly 3(a) and 3(b) and a cover 11 attached at bottom.

Now referring to Fig. 3, a cross-sectional view of the leakage proof electric water pump is illustrated. The leakage proof electric water pump comprises of a volute casing 1 mounted on upper part of leakage proof electric water pump; a washer 2; a housing 3 for accommodating plurality of electric water pump components such as a rotor assembly 4, a cylindrical bush 12, a rotor 5, a rotor casing 6 with shaft 7 and a printed circuit board (PCB) 9; and a cover 11 for covering lower part of leakage proof electric water pump.

Now referring to Fig. 4, an infrared welding for joining different parts leakage proof electric water pump is illustrated. The welding joints formed by IR welding at different parts of leakage proof electric water pump includes a welding joint 13 between volute casing 1 and rotor casing 6; a welding joint 14 between rotor casing 6 and housing 3; and a welding joint 15 between housing 3 and cover 11. The execution of IR welding (CIT) over these different parts of electric water pump that provides a leakage proof electric water pump with high welding strength. The I. R welding j oints made in the leakage proof electric water in accordance with the present invention in comparison with conventional O-ring type sealing joint provide four times improvement in leakage characteristics.

Now referring to Fig. 5, the welding rib 16 for joining different parts together is illustrated. The welding rib 16 is inserted in the grooves of each part that is to be welded. These welding ribs 16 provide a better welding strength and enhances the life of the leakage proof electric water pump. The welding involves mainly three steps including: (a) joining the rotor casing 6 and housing 3 together by IR welding; (b) joining rotor casing 6 and volute casing 1 through I.R welding; and (c) joining the housing 3 and cover 11 through I.R. welding.

The present invention provides a highly efficient and affordable electrically controlled BLDC motor-based leakage proof electric water pump having applications in cooling of engine, power electronics inverter and battery in electric/hybrid vehicles. During the operation of leakage proof electric water pump, a leakage in the pump may reduce the electric water pump. Therefore, in order to avoid such leakage, the different parts of pump are welded by infrared welding (CIT) technique.

The foregoing description of embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the invention. The embodiments were chosen and described in order to explain the principals of the invention and its practical application to enable one skilled in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated.

Claims

CLAIMS We claim:

1. A leakage proof electric water pump, comprising: a volute casing (1); a washer (2); a housing (3) with at least two mounting assembly 3(a), 3(b); a rotor assembly (4); a cylindrical bush (12); a rotor (5); a rotor casing (6); a shaft (7) inserted in the rotor casing (6); a stator assembly (8); a printed circuit board (PCB) (9); a self-tapping screw (10); and a cover (11) for covering lower part of said leakage proof electric water pump; wherein, said volute casing (1) is joined with said rotor assembly (4) via a welding joint (13), said rotor casing (6) is joined with said housing (3) through a welding joint (14) and said housing (3) is joined with said cover (11) via a welding joint (15); and said welding joints (13, 14, 15) are made through a clean infrared welding technique and using a welding rib (16) to provide leakage proof electric water pump with improved life and high welding strength.

2. The leakage proof electric pump as claimed in claim 1, wherein said leakage proof electric water pump is electrically controlled and brushless electric direct current (BLDC) motor-based.

3. The leakage proof electric water pump as claimed in claim 1, wherein said welding rib (16) is inserted in grooves of said volute casing (1), rotor assembly (4), housing (3) and said cover (11).

4. The leakage proof electric water pump as claimed in claim 1, wherein said clean infrared welding comprises steps of: (a) joining the rotor casing (6) and housing (3) together by IR welding;

(b) joining rotor casing (6) and volute casing (1) through I.R welding; and

(c) joining the housing (3) and cover (11) through I.R. welding.