Description:FIELD OF INVENTON
This invention relates to an electric motor for a submersible water pump. More particularly, this invention relates to an arrangement for cable replacement in an electric motor for a submersible water pump.

BACKGROUD OF THE INVENTION
An electric motor is an electrical machine that converts electrical energy into mechanical energy in the form of rotational movement. Generally, an electric motor comprises a motor housing (shell), a stator mounted on an inner wall of the motor housing, and a rotor located at the centre of the stator. The stator comprises winding coils. The rotor comprises magnets and spins at high speeds, providing rotational mechanical energy to the system. The electric motor used for the submersible pump requires special construction, like shape and size. These motors have a cylindrical shape, a small diameter, and a long length due to the requirement for the insertion of the submersible pump in a bore-well. The electric motor for a submersible pump comprises a motor housing in the form of a cylindrical tube (shell), a stator attached to the inner diameter of the shell at a central location, end covers both ends of the shell and a rotor supported between the two end covers and located at the radially central position of the shell.
According to one prior art of electric motor for a submersible pump, the stators are concealed and filled with epoxy resin. A motor cable is used to connect stator coils and external power source. One end of motor cable is connected to the stator coils in the epoxy resin filled concealed stator. Other end of cable is connected to the power source through controller. In practical application, there exists a requirement of cable replacement, for example due to improper handling of motor, cable cut issue arises frequently. As this motor cable is integral with the epoxy filled concealed stator, the complete stator assembly has to be replaced in case of cable cut. This leads to increase in service cost to customer and increases lead time to service motor stator by manufacturer or service provider.

In the known another prior arts of electric motor for submersible pumps, the cable is provided with male-female connector. The female part of the connector is connected to the stator coils in the epoxy resin filled stator. The male part of the connector is connected to the one end of the motor cable. Other end of motor cable is connected to the power source through the controller. The connection is made through the male-female connectors. In case the motor cable is cut or damaged, it can be replaced easily by dismantling it with the help of the male-female connector. This ensures low service cost to customer and servicing can be easily and quickly done by motor manufacturer or service provider. The drawback of the male-female connector is that contact resistance is increased which reduces the motor efficiency. Also only motor cable can be replaced. But the female portion of the connector which is integral with concealed stator cannot be replaced. Cost increases due replacement requirement of male-female connector. This type connectors can be used up to 1.5 sq.mm cable. It cannot be used above 1.5 sq.mm cable due to dimensional constraints as per IS Standard IS9283.

OBJECT OF THE INVENTION
The object of the invention is to design a power cable connection arrangement for an electric motor for a submersible pump with a resin filled stator that can be easily and quickly replaced in case of failure/damage of cable.

Another object of the invention is to design a power cable connection arrangement for an electric motor for a submersible pump with a resin filled stator which has less servicing cost.

Another object of the invention is to design a power cable connection arrangement for an electric motor for a submersible pump with a resin filled stator which does not reduce the motor efficiency due to non usage of connectors .

SUMMARY OF INVENTION
To avoid the problems mentioned above and achieve the objects, according to one embodiment of the present invention, the applicant developed an electric motor for the submersible pump, wherein it comprises:
a) A motor housing,
b) A stator,
c) A rotor,
d) A motor cable or power cable,
e) A stator cable,
Wherein;
The stator is concealed and filled with epoxy resin, and
the motor cable and the stator cable are connected to each other at connection joint, which is outside the epoxy resin filled area of the stator.

The stator area is divided into two parts; first part (shown by green colour part and numeral 61 in the figure 2), which contains stator coils, is filled with epoxy resin, and second part (shown by yellow colour part and numeral 62 in figure 2) is kept empty and not filled with epoxy resin, and the connection joint is placed in the second part.

The second part of the stator is closed from all sides and is made leak proof by providing a rubber grommet on the motor cable and tightening it by a cable clip. This ensures no contact of water/Oil and connection in the second part of the stator.

The motor cable and the stator cable are connected to each other at connection joint, with the help of known methods like soldering, bolting, clamping etc.

The stator cable in the second part of the stator has provision of excess length to facilitate repair/servicing of the cable.; so that the motor and the stator cables with connection joint can be brought out of the second part of the stator by loosening the cable clip and removing the rubber grommet to replace the motor cable in case of damage.

A method of servicing /repairing the damaged motor cable (55) of the electric motor for the submersible pump comprised following steps:
a) Removal of clip,
b) Removal of grommets,
c) Taking out the connection joint from the second part of the stator,
d) Disconnecting the connection joint and removal of damaged motor cable from the stator cable,
e) Connecting a new/ repaired motor cable to the stator cable at the connection joint,
f) Insertion of the connection joint, into the second part of the stator,
g) Re-fitting of rubber grommets on the motor cable and clamping it with the clip.

The motor cable (55) and the stator cable (56) are connected to each other at connection joint (63) by known methods selected from the group of soldering, bolting, clamping etc.

With the above arrangements, the motor cable in the electric motor can be easily and quickly serviced or replaced. This also reduces cost of servicing/ repairing the electric motor for a submersible pump and also does not reduce efficiency of motor.

BRIEF DESCRIPTION OF DRAWINGS:

Figure 1 is a pictorial cross section side view of an electric motor of a submersible pump according to one prior art of the present invention.
Figure 2 is a pictorial cross section side view of an electric motor of a submersible pump according to one embodiment of the present invention.
Figure 3 is an exploded view of an electric motor of a submersible pump according to one embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT:

Embodiments of the present invention will now be explained with the help of the figures herein below. All the aspects described herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating preferred embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope herein without departing from the spirit and scope thereof, and the present invention herein includes all such modifications.

Referring to Figure 1, according to one of the prior art of the present invention, an electric motor (1) of a submersible pump comprises; a motor housing (2), a stator (3), a rotor (4), a motor cable (5) and stator coils (6). The stator (3) is concealed by filling epoxy resin (7) in it. A motor cable (5) is used to connect stator coils (6) and an external power source. One end of motor cable (5) is connected to the stator coils (6) with the help of pins (10), in the epoxy resin (7) filled concealed stator (3). The other end of motor cable (5) is connected to the power source through a controller. Motor cable (5) is fitted in the housing (2) with a rubber grommet (8) and a sealing clip (9) to make the motor (1) leak proof. In practical applications, due to improper handling, motor cable (5) cut issues arise frequently. As this motor cable (5) is integral with the epoxy resin (7) filled concealed stator (3), the complete stator assembly has to be replaced in the event of a cable cut. This leads to increase in service costs to customer and increase in lead time for service of motor and stator by the manufacturer.

Now, referring to figures 2 and 3, according to one embodiment of the present invention, an electric motor (51) of a submersible pump comprises (Not shown); a motor housing (52), a stator (53), a rotor (54), motor cable (55) and a stator cable (56). The stator (53) of the motor (51) is concealed by filling epoxy resin (58) around it.

The stator (53) area is atleast divided into two parts; first part (61), which comprises stator coils (57) and is filled with epoxy resin (58) and a second part (62), which is not filled with epoxy resin. The connection joint (63) is disposed in the second part (62). One end of the stator cable (56) is connected to the stator coils (57) in the first part (61) of the stator (53) area, and the other end of the stator cable (56) is connected to the one end of the motor cable (55) at the connection joint (63) in the second part (62) of the stator (53) area. The other end of the motor cable (55) is connected to the power source through the controller (Not shown).

According to an embodiment, the second part (62) of the stator (53) is closed from all sides and is configured to make it leak proof by providing a rubber grommet (64) on the motor cable and tightening it with a cable clip (65). This ensures no contact between water or oil, and the connection joint (63) in the second part (62) of the stator (53).

The motor cable (55) and stator cable (56) are connected to each other at the connection joint (63) with the help of standard methods like soldering, bolting, clamping, etc.

The stator cable (56) in the second part (62) of the stator (53) has provision of excess length to facilitate repair/servicing of cable, so that in case of any damage to cable or any repair work, the motor cable (55) and the stator cable (56) with connection joint (63) can be brought out of the second part (62) of the stator (53) by loosening the cable clip (65) and removing the rubber grommet (64) to replace the motor cable (55).

A method of servicing /repairing the damaged motor cable (55) of the electric motor for the submersible pump comprised following steps:
a) Removal of clip (65),
b) Removal of grommets (64),
c) Taking out the connection joint (63) from the second part (62) of the stator (53),
d) Disconnecting the connection joint (63) and removal of damaged motor cable (55) from the stator cable (56),
e) Connecting a new/ repaired motor cable (55) to the stator cable (56) at the connection joint (63),
f) Insertion of the connection joint (63), into the second part (62) of the stator (53),
g) Re-fitting of rubber grommets (64) on the motor cable (55) and clamping it with the clip (65)

With the above arrangements, the motor cable (55) in the electric motor (51) can be easily and quickly serviced or replaced. This also reduces cost of servicing/ repairing the electric motor for a submersible pump without hampering efficiency of motor.

Although the invention has been described with regard to its embodiments, specific embodiments, and various examples, which constitute the best mode presently known to the inventors, it should be understood that various changes and modifications, as would be obvious to one having the ordinary skill in this art, may be made without departing from the scope of the invention. The scope of the claims should not be limited by the preferred embodiments set forth in the examples, but should be given the broadest interpretation consistent with the description as a whole. All changes that come with the meaning and range of equivalency of the claims are to be embraced within their scope.
, Claims:WE CLAIM:

Claim 1: an electric motor (51) of a submersible pump comprises;
a) A motor housing (52),
b) A stator (53),
c) A rotor (54),
d) motor cable (55),
e) stator cable (56)
Wherein;
The stator (53) of the motor (51) is concealed by filling epoxy resin (58) around it, and
the motor cable (55) and the stator cable (56) are connected to each other at connection joint (63) which is disposed outside the epoxy resin filled area (61) of the stator (53).

Claim 2: An electric motor (51) for the submersible pump as claimed in claim 1, wherein; the stator (53) area is divided into atleast two parts; a first part (61), accommodating the stator coils (57) and is filled with epoxy resin (58), and second part (62) without epoxy resin, and the connection joint (63) is disposed in the second part (62).

Claim 3: An electric motor (51) for the submersible pump as claimed in claim 2, wherein; the second part (62) of the stator (53) is closed from all sides, and is configured to be leak proof arrangement (64) and a fastening arrangement (65) for motor cable (55) and stator cable (56).

Claim 4: An electric motor (51) for the submersible pump as claimed in claim 3, wherein; the said leak proof arrangement is a rubber grommet (64) on the motor cable (55).

Claim 5: An electric motor (51) for the submersible pump as claimed in claim 3, wherein; the said fastening arrangement for motor cable (55) and stator cable (56) is by a cable clip (65).
Claim 6: An electric motor for the submersible pump as claimed in claim 3, wherein; the motor cable (55) and the stator cable (56) are connected to each other at connection joint (63) by known methods selected from the group of soldering, bolting, clamping etc.

Claim 7: An electric motor for the submersible pump as claimed in claim 2, wherein; the stator cable (56) in the second part (62) of the stator (53) has provision of excess length to facilitate repair/servicing of cable.

Claim 8: A method of servicing /repairing the damaged motor cable (55) of the electric motor for the submersible pump comprised following steps:
a) Removal of clip (65),
b) Removal of grommets (64),
c) Taking out the connection joint (63) from the second part (62) of the stator (53),
d) Disconnecting the connection joint (63) and removal of damaged motor cable (55) from the stator cable (56),
e) Connecting a new/ repaired motor cable (55) to the stator cable (56) at the connection joint (63),
f) Insertion of the connection joint (63), into the second part (62) of the stator (53),
g) Re-fitting of rubber grommets (64) on the motor cable (55) and clamping it with the clip (65)

Claim 9: A method of servicing /repairing the damaged motor cable (55) of the electric motor for the submersible pump wherein; connecting and disconnecting of the connection joint (63) are by known methods selected from the group of soldering, bolting, clamping etc.