FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
[See section 10 and rule 13]
TITLE OF THE INVENTION
SYSTEM FOR OPERATING A CONICAL MILLING MACHINE IN A PREDEFINED TEMPERATURE RANGE
2. APPLICANT
Name
Nationality
Address
IDEX INDIA PVT LTD
INDIA
REVENUE SURVEY NO. 256, MANJUSAR – G.I.D.C., MANJUSAR, SAVLI ROAD, VADODARA - 391775, GUJARAT, INDIA
The following specification particularly describes and ascertains the nature of the invention and the manner in which it is to be performed.

SYSTEM FOR OPERATING A CONICAL MILLING MACHINE IN A PREDEFINED TEMPERATURE RANGE
TECHNICAL FIELD
[0001] The present disclosure relates generally to conical milling machines for milling pharmaceutical products in a predefined temperature range, and more specifically to reducing excessive heat produced in milling chamber of such milling machines.
BACKGROUND
[0002] Screen milling/conical milling technology is being used for achieving uniform particle size distributions and deagglomeration dispersions in the pharmaceutical, food and fine chemical industries.
[0003] An example of such conical milling machine is Quadro® Comil® that is being used in major manufacturing facilities worldwide and is the leading technology in uniform size reduction, sieving/screening, deagglomeration and homogenous dispersion. The Comil®’s proprietary, advanced screen milling size reduction technology has been refined through thousands of applications to deliver reliable scalability, repeatability and performance.
[0004] However, conical milling processes/machines face a major challenge of heat addition while milling heat sensitive products. The addition of heat during milling degrades, and reduces effectiveness of ingredients, melts/burns ingredients, causes sticking/choking in the milling chamber, generates black particles, and reduce milling capacity due to frequent start/stop of the milling machine.
[0005] Multiple solutions have been proposed to overcome the afore-mentioned drawbacks. One such solution includes circulation of chilled water and purging dry nitrogen in the milling chamber. However, it results in an inconsistent output, and high dusting requirement. Also, Quadro® Comil® do not have any fixed solution for heat sensitive products.

[0006] Therefore, in light of the foregoing discussion, there exists a need to overcome the aforementioned drawbacks associated during milling in the conventional conical milling machines, and to strike a balance between heat generation and pharmaceutical milling size reduction due to the challenges posed in products with low melting points.
SUMMARY
[0007] This summary is provided to introduce concepts related to reduce excessive heat generated during milling of pharmaceutical products in conical milling machines. The concepts are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
[0008] Other and further aspects and features of the disclosure will be evident from reading the following detailed description of the embodiments, which are intended to illustrate, not limit, the present disclosure.
[0009] In accordance with an embodiment of the present disclosure, there is provided a conical milling apparatus that includes a milling chamber for receiving a pharmaceutical product for milling, and an automatic liquid nitrogen filling system for operating the milling chamber in a predefined temperature range. The automatic liquid nitrogen filling system includes first and second temperature sensors communicatively coupled to the milling chamber, wherein the first temperature sensor is configured to sense a screen temperature of the milling chamber, and the second temperature sensor is configured to sense a product out temperature, a control panel to enable the user to set a predefined screen temperature and a predefined product out temperature, and a low temperature box communicatively coupled to the milling chamber, the control panel, and the first and second temperature sensors. The low temperature box includes a suction manifold coupled to an inlet of a liquid nitrogen tank for purging liquid nitrogen inside the milling chamber, and a suction control unit coupled to the suction manifold for controlling the supply of the liquid nitrogen inside the milling

chamber based on temperature difference between temperature sensed by the first and second temperature sensors, and the predefined screen and product out temperature.
[00010] In accordance with another embodiment of the present disclosure, there is provided an automatic liquid nitrogen filling system for operating a milling chamber of a conical milling machine in a predefined temperature range, that includes first and second temperature sensors communicatively coupled to the milling chamber, wherein the first temperature sensor is configured to sense a screen temperature of the milling chamber, and the second temperature sensor is configured to sense a product out temperature, a control panel to enable the user to set a predefined screen temperature and a predefined product out temperature, and a low temperature box communicatively coupled to the milling chamber, the control panel, and the first and second temperature sensors. The low temperature box includes a suction manifold coupled to an inlet of a liquid nitrogen tank for purging liquid nitrogen inside the milling chamber, and a suction control unit coupled to the suction manifold for controlling the supply of the liquid nitrogen inside the milling chamber based on temperature difference between temperature sensed by the first and second temperature sensors, and the predefined screen and product out temperature.
BRIEF DESCRIPTION OF THE DRAWINGS
[00011] The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the present disclosure is not limited to specific methods and instrumentalities disclosed herein. Moreover, those in the art will understand that the drawings are not to scale. Wherever possible, like elements have been indicated by identical numbers.
[00012] Embodiments of the present disclosure will now be described, by way of example only, with reference to the following diagrams wherein:

[00013] FIG.1 illustrates a block diagram of a conical milling apparatus, in accordance with an embodiment of the present disclosure;
[00014] FIG.2 illustrates a conical milling apparatus provided with an integrated automatic liquid nitrogen filling system for operating in a predefined temperature range, in accordance with an embodiment of the present disclosure; and
[00015] FIGs.3A and 3B illustrate an existing conical milling machine to which a cold box is retrofitted to, in accordance with an embodiment of the present disclosure.
DETAILED DESCRIPTION OF THE DRAWINGS
[00016] A few aspects of the present disclosure are explained in detail below with reference to the various figures. Example implementations are described to illustrate the disclosed subject matter, not to limit its scope, which is defined by the claims. Those of ordinary skill in the art will recognize a number of equivalent variations of the various features provided in the description that follows.
[00017] The primary aim of the present disclosure is to provide a conical milling machine that operates in a predefined temperature range to reduce excessive heat generated in milling chamber during milling of pharmaceutical products. The operation of the milling chamber in the pre-defined temperature range eliminates sticking and melting of products, eliminates moisture content and screen binding, facilitates un-interrupted milling process, maintains product flow-ability, enhances safety, improves productivity, avoids labor waste for maintaining cleanliness, and thereby accelerates sales growth and increases overall revenue.
[00018] Various embodiments are further described herein with reference to the accompanying figures. It should be noted that the description and figures relate to exemplary embodiments and should not be construed as a limitation to the subject matter of the present disclosure. It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the subject matter of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the subject matter of the present disclosure, as

well as specific examples, are intended to encompass equivalents thereof. Yet further, for the sake of brevity, operation or working principles pertaining to the technical material that is known in the technical field of the present disclosure have not been described in detail so as not to unnecessarily obscure the present disclosure.
[00019] FIG.1 illustrates a block diagram of a conical milling apparatus 100, in accordance with an embodiment of the present disclosure.
[00020] The conical milling apparatus 100 includes a milling chamber 101 that includes an infeed hopper for receiving pharmaceutical products for the purpose of milling to a predefined size.
[00021] The milling chamber 101 described herein is similar to that of Quadro® Comil® that is being used in major manufacturing facilities worldwide and is the leading technology in uniform size reduction, sieving/screening, deagglomeration and homogenous dispersion. The Comil®’s proprietary, advanced screen milling size reduction technology has been refined through thousands of applications to deliver reliable scalability, repeatability and performance.
[00022] The conical milling apparatus 100 further includes first and second temperature sensors 102 and 103 that are communicatively coupled to a control panel 104. In an example, each of the first and second temperature sensors 102 and 103 are resistance temperature detectors (RTDs).
[00023] The first temperature sensor 102 is configured to sense temperature of screen at highest friction during particle size reduction between impeller and screen, and the second temperature sensor 103 is configured to sense a product out temperature. The screen temperature is the highest temperature developed at friction portion during particle size reduction between impeller and screen, and the product out temperature is the temperature at discharge of product after milling the product. In an example, the product out temperature has to be maintained just before the control room temperature i.e. in range of 10C to 25C, and the screen temperature has to be maintained in safe range, i.e. before melting point of the product.

[00024] In an embodiment of the present disclosure, the control panel 104 includes a display screen to indicate the current temperature of the first and second temperature sensors 102 and 103. In another embodiment of the present disclosure, the control panel 104 enables the user to set the screen temperature, and product out temperature.
[00025] The conical milling apparatus 100 further includes a cryogenic box 105 that includes a discharge manifold 106, and a suction control system 107. The suction control system 107 includes a suction manifold coupled to an inlet 108 for purging liquid nitrogen (LN2) inside the milling chamber 101, and a suction control unit coupled to the suction manifold for controlling the supply of LN2. The discharge manifold 106 is coupled to a discharge outlet 109 of the milling chamber 101 for discharging the used Nitrogen gas from the milling chamber 101. In an embodiment of the present disclosure, the cryogenic box 105 may be hereinafter referred to as a low temperature box.
[00026] The conical milling apparatus 100 further includes a nitrogen tank 110 for storing liquid nitrogen (LN2) and providing to the milling chamber 101 through the suction control system 107. In an example. In an example, the temperature inside the nitrogen tank 110 is -196° C. The tank 110 is provided with a pressure regulator 111 for regulating the pressure of LN2 therein, and is further provided with a vent valve 112, a drain valve 113, and a pressure gauge 114.
[00027] In an embodiment of the present disclosure, the suction control system 107 controls purging of LN2 inside the milling chamber 101, based on an input received from the control panel 104. The control panel 104 provides control instructions to the suction control system 107 based on the temperatures recorded by the temperature sensors 102 and 103. In an example, if the temperatures recorded by the temperature sensors 102 and 103 are higher than the temperatures set by the user, then it means that there is excessive heat inside the milling chamber 101, and a higher amount of LN2 has to be provided inside the milling chamber 101 to cool it down. Similarly, if the temperatures recorded by the temperature sensors 102 and 103 is less than the temperatures set by the user, then it means that the supply of LN2 inside the milling chamber 101 has to be reduced. In an embodiment of the present disclosure, the temperature to be maintained

inside the milling chamber 101 is in the range of 10°C to 25°C. In an example, the maximum temperature reached at screen is 80°C.
[00028] Thus, the temperature sensors 102, and 103, the control panel 104, the suction control system 107, and the tank 110 together form an autofill system that continuously replenish the milling chamber 101 with a right amount of LN2 required to maintain a specified temperature range inside the milling chamber 101. The milling chamber 101 is continually cooled with LN2 from the tank 110 before and during the grinding process. The autofill system reduces the initial stabilizing temperature, overcomes difficulties in milling of critical products and enables achieving a balance between milling size reduction and heat generation. The autofill system provides a close loop integrated solution for conical milling machines to help to cover come milling challenge for heat sensitive products and deliver continuous and consistent results.
[00029] In an embodiment of the present disclosure, the conical milling apparatus 100 employs vacuum Insulation on piping to avoid condensation and icing formation. The vacuum insulation is required to insulate effect of liquid nitrogen in core piping to expose to environment which may be seen in form of condensation and icing on outer pipes.
[00030] The closed loop integrated system avoids direct human contact with LN2 and makes this low temperature milling very safe. The controlled temperature cooling results in a perfect milling efficiency. Also, the liquid nitrogen (LN2) operates at very less pressure and has very less consumption during milling.
[00031] In an embodiment of the present disclosure, the autofill system may be integrated with a conical milling machine to form a new design of a conical milling apparatus. In another embodiment of the present disclosure, the autofill system may be retrofitted to an existing conical milling apparatus such as Quadro® Comil®.
[00032] FIG.2 illustrates a conical milling apparatus 200 provided with an integrated automatic liquid nitrogen filling system for operating in a predefined temperature range, in accordance with an embodiment of the present disclosure.

[00033] The conical milling apparatus 200 includes a milling chamber 201 for milling pharmaceutical products to a predefined size, an inlet 202 to receive a supply of liquid nitrogen (LN2) from a utility such as a nitrogen tank, an LN2 inlet adapter 203 in the milling chamber 201, a control panel 204 that includes a first button (not shown) for enabling a user to set a screen temperature, and a second button (not shown) for enabling a user to set a product out temperature, and a first outlet 207 to connect to an N2 exhaust. The LN2 inlet adapter 203 is also hereinafter referred to as LN2 induction ring or Cryo ring. The LN2 inlet adapter 203 is designed for peripheral uniform and centralized cooling effect, and cryo ring effectiveness was 270° with respect to main port.
[00034] In operation, the pressure of LN2 is maintained in a range of 3 to 4 Bar g at the inlet 202, and the pressure of N2 is maintained in a range of 6 to 8 Bar g at the first outlet 207. For starting the milling process, the user may set the temperatures, start liquid nitrogen supply, achieve set temperature without product for a maximum of 5 min, and start feeding material in the milling chamber 101.
[00035] In an embodiment of the present disclosure, the control panel 204 of the conical milling apparatus 200 may implement software tools like daily management and Goal Deployment process (GDP) to review status of any project/activities within one or more interested team members.
[00036] FIG.3A illustrates an existing conical milling machine 300 to which a cold box 301 is retrofitted to, behind a corresponding existing control panel 302, in accordance with an embodiment of the present disclosure. The cold box 301 may be similar to the low temperature box 105. In an embodiment of the present disclosure, the existing control panel 302 of the machine 300 may be modified to suit to the requirements of operating the conical milling machine 300 in the predefined temperature range of 10°C to 25°C. Also, the cold box 301 may be mobile and compact in size, without requiring any additional space.
[00037] FIG.3B illustrates an existing conical milling chamber 303 to which a cold box 304 and a control panel 306 is retrofitted to, in accordance with an embodiment of the

present disclosure. Herein, the cold box 304 is retrofitted at a center position, and a new adapter plate 307 is installed for mounting the control panel 306.
[00038] The above description does not provide specific details of the manufacture or design of the various components. Those of skill in the art are familiar with such details, and unless departures from those techniques are set out, techniques, known, related art or later developed designs and materials should be employed. Those in the art can choose suitable manufacturing and design details.
[00039] Note that throughout the disclosure, numerous references may be made regarding servers, services, engines, modules, interfaces, portals, platforms, or other systems formed from computing devices. It should be appreciated that the use of such terms is deemed to represent one or more computing devices having at least one processor configured to or programmed to execute software instructions stored on a computer-readable tangible, non-transitory medium or also referred to as a processor-readable medium. For example, a server can include one or more computers operating as a web server, database server, or another type of computer server in a manner to fulfill described roles, responsibilities, or functions. Within the context of this document, the disclosed devices or systems are also deemed to comprise computing devices having a processor and a non-transitory memory storing instructions executable by the processor that cause the device to control, manage, or otherwise manipulate the features of the devices or systems.
[00040] It should be understood, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise, as apparent from the discussion herein, it is appreciated that throughout the description, discussions utilizing terms such as “receiving,” or “authenticating,” or “facilitating,” or “executing,” or “capturing,” or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.

[00041] The exemplary embodiment also relates to an apparatus for performing the operations discussed herein. This apparatus may be specially constructed for the required purposes, or it may comprise a general-purpose computer selectively activated or reconfigured by a computer program stored in the computer. Such a computer program may be stored in a computer-readable storage medium, such as, but is not limited to, any type of disk including floppy disks, optical disks, CD-ROMs, and magnetic-optical disks, read-only memories (ROMs), random access memories (RAMs), EPROMs, EEPROMs, magnetic or optical cards, or any type of media suitable for storing electronic instructions, and each coupled to a computer system bus.
[00042] Further, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. It will be appreciated that several of the above-disclosed and other features and functions, or alternatives thereof, may be combined into other systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may subsequently be made by those skilled in the art without departing from the scope of the present disclosure as encompassed by the following claims.
[00043] The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others.
[00044] It will be appreciated that variants of the above-disclosed and other features and functions, or alternatives thereof, may be combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.

[00045] Modifications to embodiments of the present disclosure described in the foregoing are possible without departing from the scope of the present disclosure as defined by the accompanying claims. Expressions such as “including”, “comprising”, “incorporating”, “have”, “is” used to describe and claim the present disclosure are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural.

Claims: We Claim:
1. A conical milling apparatus comprising:
a milling chamber for receiving a pharmaceutical product for milling; and
an automatic liquid nitrogen filling system for operating the milling chamber in a predefined temperature range, wherein the automatic liquid nitrogen filling system comprises:
first and second temperature sensors communicatively coupled to the milling chamber, wherein the first temperature sensor is configured to sense a screen temperature of the milling chamber, and the second temperature sensor is configured to sense a product out temperature;
a control panel to enable the user to set a predefined screen temperature and a predefined product out temperature; and
a low temperature box communicatively coupled to the milling chamber, the control panel, and the first and second temperature sensors, the low temperature box comprising:
a suction manifold coupled to an inlet of a liquid nitrogen tank for purging liquid nitrogen inside the milling chamber; and
a suction control unit coupled to the suction manifold for controlling the supply of the liquid nitrogen inside the milling chamber based on temperature difference between temperature sensed by the first and second temperature sensors, and the predefined screen and product out temperature.
2. The conical milling apparatus as claimed in claim 1, wherein each of the first and second temperature sensors is a resistance temperature detector (RTD).
3. The conical milling apparatus as claimed in claim 1, wherein the product out temperature is a temperature at discharge of product after milling.

4. The conical milling apparatus as claimed in claim 1, wherein the product out temperature is in the range of 10C to 25C.
5. The conical milling apparatus as claimed in claim 1, wherein the screen temperature is maintained before melting point of the product.
6. The conical milling apparatus as claimed in claim 1, wherein the low temperature box comprises a discharge manifold coupled to a discharge outlet of the milling chamber for discharging used nitrogen gas from the milling chamber.
7. An automatic liquid nitrogen filling system for operating a milling chamber of a conical milling machine in a predefined temperature range, wherein the automatic liquid nitrogen filling system comprises:
first and second temperature sensors communicatively coupled to the milling chamber, wherein the first temperature sensor is configured to sense a screen temperature of the milling chamber, and the second temperature sensor is configured to sense a product out temperature;
a control panel to enable the user to set a predefined screen temperature and a predefined product out temperature; and
a low temperature box communicatively coupled to the milling chamber, the control panel, and the first and second temperature sensors, wherein the low temperature box comprises:
a suction manifold coupled to an inlet of a liquid nitrogen tank for purging liquid nitrogen inside the milling chamber; and
a suction control unit coupled to the suction manifold for controlling the supply of the liquid nitrogen inside the milling chamber based on temperature difference between temperature sensed by the first and second temperature sensors, and the predefined screen and product out temperature.

8. The automatic liquid nitrogen filling system as claimed in claim 7, wherein each of the first and second temperature sensors is a resistance temperature detector (RTD).
9. The automatic liquid nitrogen filling system as claimed in claim 7, wherein the product out temperature is a temperature at discharge of product after milling.
10. The automatic liquid nitrogen filling system as claimed in claim 7, wherein the product out temperature is in the range of 10C to 25C.