DESC:PUMP WITH IN BUILT LIQUID LEVEL CONTROLLER

FIELD OF INVENTION
The present invention relates to an electric motor pump fitted with inbuilt controller to control the electric motor pump. The controller is connected to the liquid level sensors for selectively activating and deactivating the electric motor pump in order to maintain uninterrupted supply of liquid from the over head tank / reservoir. Advantageously the circuitry of controller according to the present invention is inbuilt to the terminal box of the electric motor pump and eliminates the requirement of separate controller.

DESCRIPTION OF PRIOR ART
Pumps typically have an inlet which is located at the suction side of the pump where the liquid enters the pump - for example from sump and delivered through an outlet located above overhead tanks / reservoir The operation of the pump creates suction by building lower pressure at the suction side, so that liquid can enter the pump through the inlet. The pump operation also causes higher pressure at the discharge side so that liquid can be delivered to the overhead tanks / reservoir through the outlet.

In many homes and other public places, ground water is used, which is pumped up to overhead tanks / reservoir using pumps. In such installations by and large the pump is manually switched on when water level is low / or no water in the over head tank / reservoir and manually switched off when the over head tank / reservoir is filled with sufficient water. Such type of manual operation of the pump always results in interruption in the supply of water which is undesirable.

Automatic Controlling of the pumps is often a necessity to avoid wastage of water as well as to ensure uninterrupted supply of water without human interference. The usage of controllers with water level monitoring system is known in the art for automatic controlling of the pumps.

The water level control and monitoring system comprises the water level monitoring equipment which is placed inside the over head tank / reservoir and electrically connected to the controller for controlling the working of the pump. The monitoring equipment controls different levels of water in the over head tank / reservoir by switching ‘on’ and ‘off’ of the pump to maintain defined minimum/maximum level of water in the over head tank / reservoir. The controller comprises components such as relays, timers, transistors etc.

During operation, the monitoring system which comprises devices such as floats which are positioned in the water reservoir generates signal corresponding to different water levels. The signals are fed to the controller for processing. The controller provides necessary start / stop command to the pump circuit for starting and stopping of the pump.

Different types of monitoring and systems for controlling are known in the art. In the known arrangements the controller is constructed as a separate module and is electrically connected to the monitoring equipment and the pump.

When the water level in the over head tank / reservoir reaches the pre defined minimum level the monitoring device sends signal to the controller which in turn switches the pump ‘on’. Once the water level in the reservoir reaches the pre defined maximum level the monitoring device sends signal to the controller which in turn switches the pump ‘off’. This arrangement facilitates switching ‘on’ and ‘off’ of the motor without human interference.

In the known arrangements which has controller as separate module is mounted at a place and electrically connected to the monitoring unit and the pump. Since the controller being a separate unit, the, cost of the water level monitoring system is in higher side. Also it essentially involves wiring to electrically connect the controller and the pump.

Also in the known arrangements the controller is constructed with Integrated circuits (ICs) and transistors which are sensitive to temperature and likely to malfunction at elevated temperatures.

The known regulators employ floats as the monitoring device which is likely to cause induction in the water in case of damage.

So it will be advantageous to develop a control circuitry that could be in built in the pump itself there by the need for separate controller can be eliminated.

Since the controller being the integral part of pump the need for wiring to electrically connected the pump and the controller can be eliminated.

It will be advantageous to provide a pump with inbuilt controller that is free from the problems that are associated with temperature raise so that the malfunctioning of the controller at elevated temperatures could be eliminated.

OBJECTS OF THE INVENTION
One or more of the problems of the conventional prior art may be overcome by various embodiments of the present invention.

It is another object of the present invention to eliminate the requirement of separate controller for water level control function.

It is another object of the present invention to provide an electric motor pump with inbuilt water level control.

It is another object of the present invention wherein the control circuitry for controlling the water level is advantageously embedded in the pump terminal box itself.

It is another object of the present invention wherein the control circuitry of present invention is constructed using Diodes and resistors which facilitates working of the controller free from malfunctioning due to raise in temperature.

It is another object of the present invention wherein the circuitry construction of the controller is based on 12V DC circuitry for enhanced safety.

SUMMARY OF INVENTION
Thus according to the embodiment of the present invention there is provided a liquid level controller for pump comprises of a water pump is in flow communication with water tank through the tank inlet pipe line; a water level controller comprising a plurality of controlling components including a selector switch for the mode selection for the control of the water pump either in manual mode or auto mode are configured inter connected in a pre defined manner to facilitate the control of the water pump in manual / automatic mode according to the mode of selection and a water level sensor for sensing the water level mounted in the water tank to detect water level and to communicate with the water level controller to automatically control the water pump when auto mode is selected.

It is another aspect of the present invention, the controlling components for the control of the water pump are configured and inter connected in a pre defined manner to facilitate the control of the water pump in manual / automatic mode according to the mode of selection is constructed as a module.

It is another aspect of the present invention, wherein the module is mounted within the terminal box of the water pump.

It is another aspect of the present invention, wherein the selector switch has the knob for the selection of manual/auto mode protrudes through a small opening provided in the terminal box cover.

It is another aspect of the present invention, wherein the water level sensor works on 12 V DC for enhanced safety.
BRIEF DESCRIPTION OF THE DRAWINGS:
Figure 1 of the drawing schematically illustrates prior art water level control arrangement.
Figure 2 of the drawing is the schematic of water level controller (1) according to the present invention.
Figure 3 of the drawing schematically illustrates water level controller (1) constructed as a module according to the present invention.
Figure 4 of the drawing schematically illustrates water level controller (1) mounted inside the terminal box of the pump motor according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING FIGURES
As known, water level controller is a device which works automatically to monitor and control the availability of water to a pre determined level in the water storage tanks such as overhead water tanks. The controller do so by switching ‘on’ and ‘off’ the pump/ electric motor attached to the pump based on the water level information fed to it in the form of signals. The water level detection sensors are used to provide such signals deepening upon the level of water present inside the tank.
Figure 1 shows a water level control arrangement of prior art. The automatic water level control arrangement comprises of a water level controller (1), a water pump (2), a water tank (3), tank inlet pipe line (4) and water level sensor (5) for example a float switch mounted inside the water tank (3) for detecting water level and connection terminals and two wires that connects the water level sensor (5). The water level controller (1) is provided with a selector switch (6) for selecting the mode of operation of the water level controller (1) suitable for manual operation or automatic operation and optionally a ‘ON’ / ‘OFF’ switch (7). The water pump (2) is in flow communication with the water tank (3) through the tank inlet pipe line (4).

By switching the selector switch (6) to manual mode, the switching ON or OFF of the water pump (2) is carried out manually by the operation of the ON / OFF switch. By switching the selector switch (6) to automatic mode the operation of the water pump (2) is carried out automatically by the water level controller (1).
In the automatic mode, water level sensor (5) is energized with power by the water level controller (1) through one of the terminal. Whenever the water level in the water tank (2) is below the pre determined level, then the water level sensor (5) circuit is closed through the other terminal and the water pump (2) is automatically activated. By the working of the water pump (2) the water level in the water tank (3) rises and when the water tank (3) is filled with water to the pre determined level then the water level sensor (5) circuit is opened and the water pump (2) is automatically de-activated. This is achieved by the controlling components configured in the water level control unit (1). The controlling components may comprise a transformer, a contactor, a relay and the like.
The water level controller (1) known in the prior art are assembled inside a housing and is mounted as a separate unit at a place near the water pump and electrically connected to the monitoring unit and the pump. Since the water level controller (1) being a separate unit, the, cost of the water level monitoring system is in higher side. Also it essentially involves wiring to electrically connect the controller and the pump.

The water level controller (1) according to the present invention is constructed with a step down transformer, a rectifier, a capacitor , a relay working on 12 V DC, a selector switch to select the mode of operation, resistors, indicating lamps and connection terminals and constructed as a module. The components such as the transformer, the rectifier, the capacitor , the relay, the selector switch, the resistors and the indicating lamps are configured and inter connected in a pre defined manner as shown figure 2 to facilitate the control of the water pump in manual / automatic mode according to the mode of selection. The power from the a/c main is feed to step down transformer and the output from the transformer is fed to a rectifier for conversion in to 12 V DC.

During the automatic mode the relay supply the 12 V DC through resisters to the water level sensor (5) for sensing the water level, for example a float switch through sensor cables. For enhanced safety the operation of the water level sensors (5) are controlled by 12 V DC. The water level sensors (5) close the circuit and input the power to the water pump for its operation.

The water level controller (1) according to the present invention is constructed as a miniature module (8) as shown in figure 3 and advantageously mounted inside the terminal box of the pump motor itself as shown in figure 4. The mounting is such that the knob (6a) of the selector switches (6) for the selection of manual/auto mode protrudes through a small opening provided in the terminal box cover (2a) of the motor of the water pump (2). The mounting of the water level controller (1) inside the terminal box of the motor itself eliminate the need for separate housing and wiring between the water level controller (1) and the water pump (2) which provides cost effectiveness and enhanced operational reliability.

Although the invention has been described with reference to specific embodiments, these descriptions are not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments of the invention will become apparent to persons skilled in the art upon reference to the description of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. It is therefore, contemplated that the claims will cover any such modifications or embodiments that fall within the true scope of the invention. ,CLAIMS:I CLAIM
1. A liquid level controller for pump comprising:
a water pump (2) is in flow communication with water tank (3) through the tank inlet pipe line (4);
a water level controller (1) comprising a plurality of controlling components including a selector switch (6) for the mode selection for the control of the water pump (2) either in manual mode or auto mode are configured inter connected in a pre defined manner to facilitate the control of the water pump (2) in manual / automatic mode according to the mode of selection; and
a water level sensor (5) for sensing the water level mounted in the water tank to detect water level and to communicate with the water level controller (1) to automatically control the water pump (2) when auto mode is selected, characterized in that, the controlling components for the control of the water pump (2) are configured and inter connected in a pre defined manner to facilitate the control of the water pump in manual/automatic mode according to the mode of selection is constructed as a module, and
wherein the module is mounted within the terminal box of the water pump.

2. The liquid level controller for pump as claimed in claim 1, wherein the selector switch (6) has the knob (6a) for the selection of manual/auto mode protrudes through a small opening provided in the terminal box cover (2a).

3. The liquid level controller for pump as claimed in claim 1, wherein the water level sensor (5) works on 12 V DC for enhanced safety.