FORM 2
THE PATENTS ACT 1970
(39 of 1970)
AND
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rulel3)
1. TITLE OF THE INVENTION:
"TWIN COOL BOX"
2. APPLICANTS:
(a) NAME: MIRC ELECTRONICS LIMITED
(b) NATIONALITY: Indian Company incorporated under The Companies
Act, 1956
(c) ADDRESS: G-l, Onida House, MIDC, Mahakali Caves Road, Andheri (East),
Mumbai - 400093, Maharashtra, India.
3. PREAMBLE TO THE DESCRIPTION:
The following specification particularly describes the invention and the manner in which it is to be formed.

FIELD OF INVENTION:
The invention relates to a time-based multiflexing, universal, multi splitting box assembly, namely Twin cool box, for splitting the refrigerant flow between multiple indoor units connected to one outdoor unit.
BACKGROUND OF INVENTION:
Multi-Split air conditioner systems are ideal for situations where there is limited space for outdoor units. There are many manufacturers of multi-split systems and Variable refrigerant volume (VRV) systems throughout the world and it is important that the designer / technician / building owner has some practical understanding of their uses and limitations. These types of systems vary considerably from manufacturer to manufacturer particularly with reference to noise levels and the type of indoor units used. This is particularly the case with VRV systems where it is often assumed, quite erroneously, that there are few manufacturers of these systems and they are all similar.
These systems have seen an increased requirement in the recent past and are particularly popular because they require less outdoor plant space than conventional systems, are less disruptive to fit in existing buildings (particularly when occupied), are able to cool and heat through common pipework.
The traditional 'split system' is also known colloquially and more descriptively as a 'one to one split system', meaning one external condensing unit / heat pump is connected by refrigerant pipework to one indoor cooling / cooling and heating unit.
The'multi-split system uses one external unit which is connected to several indoor units. The multi-split system takes a number of different forms, as listed below, and it is essential that the designer/ technician understands the limitations of each type of system.
Master and slave system: One off external condensing unit / heat pump unit is connected to several indoor units as is typical for a multi-split system. One of the indoor units is provided with temperature controller / sensor and acts as master and the other unit(s) acts

as slaves. All indoor units will therefore function as the master setting. Master and slave units are suitable for single areas, single rooms or even multiple rooms with very similar heat gains / losses. They are not suitable for individual areas / rooms which have different heat gain / loss characteristics because the master control will sense air temperature for one area / room only and the areas / rooms will overcool or overheat.
Variable refrigerant volume (VRV) systems: Again one off condensing unit/heat pump is connected to several indoor units. VRV systems are able to provide total versatility and each indoor unit may cool / heat independently of each other. In fact, if part of a building requires cooling and other areas require heating the heat rejected for the required cooling contributes or is recovered to provide heating in the other area.
Various multi-split air conditioning air systems are known, as described hereinabove, still other multi-spilt air conditioning systems are further covered by JP4350444 filed by Hitachi. As per the disclosure therein, the systems based on this scheme are expensive and usually not universal, that is, the outdoor units, indoor units need to be purchased from same manufactures as single unit, thereby making system economically less feasible.
Another European patent application, EP1437554 discloses a solenoid valve control device and an air conditioner provided with the same for reduced power consumption but fails to throw light on split air conditioning. Also, the in-built additional components in the air conditioning device lead to a complicated construction.
Available solutions for split air conditioning are restrictive for customization, requiring specific makes of indoor units to be used with specific makes of outdoor units.
Hence, with a view of making the system less expensive and more customizable, inventors of the present invention hereby propose a novel multi splitting box, namely Twin cool box,

Summary:
In view of the above, the present invention provides an integrated Twin cool box for connecting single outdoor unit to plurality of indoor units.
In another aspect, the-Twin cool box of invention is independent of make or model of either outdoor unit or indoor unit.
In yet another aspect, the Twin cool box of invention uses time multiflexing technique to understand cooling needs of rooms containing the various indoor units.
Brief description of Drawings:
.Fig. 1 illustrates a schematic layout of the-Twin cool box of the invention.
Fig. 2 illustrates a schematic drawing of Twin cool system.
Fig. 3 illustrates schematic layout of the Controller Board
Detailed Description of Invention:
The present invention will now be described with reference to the figures and specific and optional embodiments.
The current invention describes solenoid valve-based, universal, integrated Twin cool box assembly for splitting the refrigerant flow between multiple indoor units connected to one outdoor unit wherein, microprocessor based time multiflexing intelligent controller (Fig. 3) understands the cooling needs of room by processing the signal from Indoor unit controller. The said controller (Fig. 3) drives an expander (bi-flo x'pander) (9 and/orlO) by one way solenoid valve (7 and 8, Fig.l) which gets power from the intelligent controller.
In an embodiment, the system, as illustrated in Fig. 1 and Fig. 2, comprises a Twin cool box (12), which in turn consists of a microprocessor based controller (11). The said controller analyzes signal received from the indoor units (13A and 13B, shown in Fig. 2) regarding the cooling needs of the room. The box (12) further consists of one way solenoid valves (7) and (8). The said valves (7) and (8) receive a signal from either IDUs

(13A and 13B) based on demand from the controller board. The valve further comprises a pair of bi-flow expanders (9) and (10). The Twin cool box is in communication with the Outdoor Unit (ODU) (14) and Indoor units (IDUs) (13A and 13B), through flexi unions (1, 2, 3, 4, 5 and 6). Bi-flow expanders (biflo x'pander) (9) and (10) are placed one each on suction line and liquid line to divide the refrigerant flow among each of the lines as directed by the controller. The biflo x'panders are designed to divide the refrigerant flow equally and feed both the systems. The twin-cool box is connected the IDU's and the ODU by inter-connecting pipes via flexi unions.
In an embodiment, the one way solenoid valves (7) and (8) get signals from IDUs (13A and 13B) through controller board, as in Fig. 3 vide AC1 or AC2 inputs. When the signal is received from the IDUs, a relay, selected from RL-1 or RL-2, switches on the solenoid valves (7) and/or (8). When coil (not shown) over the solenoid valve is energized, the plunger (not shown) inside the valve body lifts the ball over the valve seat and allows the refrigerant to pass through. Once IDU sends the signal that the room conditions are achieved, the valve is cut off and refrigerant flow stops.
In a preferred embodiment, the system, as illustrated in Fig. 1 and Fig. 2, comprises a Twin cool box (12), to universally connect any two IDU's to one ODU irrespective of their make, comprising of a microprocessor based controller (11) therein. The said controller analyzes signal received from the IDU's (13A and 13B), shown in Fig. 2) regarding the cooling needs of the room. The box (12) further consists of one way solenoid valves (7) and (8) operated at 230V. The said valves (7) and (8) receive a signal from either IDUs (13A and 13B) based on demand from the controller board. The valve further comprises a pair of bi-flow expanders (9) and (10). The Twin cool box is in communication with the Outdoor Unit (ODU) (14) and Indoor units (IDUs) (13A and 13B), through flexi unions (1, 2, 3, 4, 5 and 6). The one way solenoid valves (7) and (8) get signals from IDUs (13A and 13B) through controller board, as in Fig. 3 vide AC1 or AC2 inputs respectively. It uses time multiflexing to regulate the air conditioning in the rooms where the two IDU's are installed. The controller asses the needs of each of the room based on the signals received from respective IDU's. When one IDU in the system is shut, the other IDU is operated at 100% of its capacity for a periodic time or till its IDU sends a signal to reduce cooling. When both IDU's in the system are working

simultaneously, the controller controls and operates each of them on an optimally equal/proportionate capacity at the same time. Thus, with time multiflexing, the Twin cool box regulates flow of refrigerant between both IDU's of the system optimally without straining the single ODU. When the signal is received from the IDUs, a relay, selected from RL-1 or RL-2, switches on the solenoid valves (7) and/or (8). When coil (not shown) over the solenoid valve is energized, the plunger (not shown) inside the valve body lifts the ball over the valve seat and allows the refrigerant to pass through. Once IDU sends the signal that the room conditions are achieved, the valve is cut off and refrigerant flow stops.
The most preferred embodiment of the present invention thus accomplishes a process for controlling the flow of refrigerant between a plurality of IDU's (13A and 13B) and at least one ODU (14), irrespective of their individual make, characterized in that, the solenoid valve-based, universal, time multi-flexing integrated Twin-Cool box (12), connected between said plurality of IDU's (13A and 13B) and at least one ODU (14), is enabled to accomplish the said process. The said twin-cool box(14) comprises a plurality of channels for passage of refrigerant a controller (11) enabled to analyze and process signals received from IDU's (13A and 13B), means to manage flow of refrigerant through said plurality of channels as directed by the said controller, namely the one way solenoid valves (7 and 8), and means to divide refrigerant flow received from said one way solenoid valves as directed by said controller and output the said refrigerant flow to said plurality of IDU's, namely biflo x'panders (9 and 10). The said Twin-Cool box (12) is enabled to perform time multi-flexing operation, in coordination with said at least one ODU (14) and said plurality of IDU's (13A and 13B), at 0 - 100 % capacity during operating conditions. The said bi-flow x'panders (9 and 10) are designed to divide refrigerant flow equally and are placed on suction-line and liquid-line of each of the said plurality of IDU's (13A and 13B). The said Twin-Cool (12) box is connected to the said at least one ODU (14) with the said plurality of IDU's (13A and 13B) via flexi unions (1, 2, 3, 4, 5 and 6) through connecting pipes. The said Twin-Cool box is connected to the said at least one ODU with at least two IDU's.

Example:
A system as shown in Fig. 2comprising an outdoor unit (14) connected to solenoid valve (12), whereby the refrigerant flow is split and sent to the individual indoor unit depending on the room conditions as reported by the indoor control units sensor (13A and 13B). The signals obtained by IDUs are transferred to controller board. The controller board, depending on the room conditions, allows passage of the refrigerant through solenoid valves (7 and/or 8) by energizing them. Once the controller receives the signal that the room conditions have been achieved, the controller shuts down the solenoid valve and thereby stops flow of refrigerant.

We Claim,
1. A process for controlling the flow of refrigerant between a plurality of Indoor Air-conditioning Units (IDU) and at least one Outdoor Air-conditioning Unit (ODU) characterized in that, a solenoid valve-based, universal, time multi-flexing integrated Twin-Cool box, connected between said plurality of IDU's and at least one ODU, enabled to accomplish the said process, wherein, the said twin-cool box comprises:
a plurality of channels for passage of refrigerant,
a controller enabled to analyze and process signals received from IDU's,
a plurality of means to manage flow of refrigerant through said plurality of channels as directed by the said controller
and
a plurality of means to divide refrigerant flow received from said means to manage flow of refrigerant as directed by said controller and output the said refrigerant flow to said plurality of IDU's.
2. The process for controlling the flow of refrigerant as claimed in claim 1, wherein, the said Twin-Cool box is enabled to perform time multi-flexing operation, in coordination with said at least one ODU and said plurality of IDU's, at 0 - 100% capacity during operating conditions.
3. The process for controlling the flow of refrigerant as claimed in claim 1, wherein, said means to manage flow of refrigerant through said plurality of channels as directed by the said controller are one way solenoid valves.
4. The process for controlling the flow of refrigerant as claimed in claims 1 and 3, wherein, means to divide refrigerant flow received from said one way solenoid valve as directed by said controller and output the said refrigerant flow to said plurality of IDU's is a bi-flow x'pander.

5. The process for controlling the flow of refrigerant as claimed in claims 1 and 4, wherein, said bi-flow x'panders, designed to divide refrigerant flow equally are placed on suction-line and liquid-line of each of the said plurality of IDU's
6. The process for controlling the flow of refrigerant as claimed in claim 1, wherein, the said Twin-Cool box is connected to the said at least one ODU with the said plurality of IDU's via flexi unions through connecting pipes.
7. The process for controlling the. flow of refrigerant as claimed in claim 1, wherein, the said Twin-Cool box is connected to the said at least one ODU with at least two IDU's.