FORM 2
THE PATENTS ACT 1970
(39 of 1970)
&
The Patent Rules 2003
PROVISIONAL SPECIFICATION
(see sections 10 & rule 13)
1. TITLE OF THE INVENTION
"GEMSTONE PROCESSING MACHINE"

2. APPLICANT (S)
NAME
SAHAJANAND TECHNOLOGIES
PVT LTD

NATIONALITY
Indian Company

ADDRESS
Sahajanand House, Parsi Street, Saiyedpura, Surat-395003, Gujarat, India

3. PREAMBLE TO THE DESCRIPTION
PROVISIONAL SPECIFICATION
1 AUG 2008
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The following specification describes the nature of the invention


TECHNICAL FIELD:
The subject matter described herein, in general, relates to a machine for processing a gemstone and in particular, relates to a laser gemstone processing machine providing a curved path for a laser beam.
BACKGROUND:
Typically, a raw gemstone i.e. a gemstone as found in its natural state, has a highly irregular geometry and includes many contaminations. A series of steps are involved in processing the raw gemstone to obtain a finished gemstone. Major steps involved in the processing of a raw gemstone are planning, cleaving or sawing, bruting, polishing, and final inspection. A 3D profile of the raw gemstone is obtained during the planning process and a best shape for the finished gemstone to be cut from the raw gemstone is selected. Once the best shape of the gemstone is finalized, the gemstone is sent to sawing machine for sawing.
Precise sawing and bruting according to a selected best shape is especially important in case of gemstones, such as diamonds, where the monetary value of the gemstone depends on its size. To achieve precise cutting of a diamond, predetermined marking are made on the surface of the diamond prior to processing and actual processing of the diamond is performed in accordance with the markings.
Once the diamond is cut, it is sent to a bruting machine that brutes the girdle of the diamond. Conventionally, the bruting was done by rubbing the diamond with another diamond. With recent advancement in technology, numerous computer assisted systems
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are employed to cut and brute a diamond by laser. Such systems perform the various steps involved in the diamond processing. Such computerized laser cutting systems work effectively without or with very little human intervention.
Generally, a non-contact process is employed for sawing and bruting of a diamond. In the non-contact process, a laser beam is utilized for performing the desired function. The diamond sawing or bruting machines are calibrated in such a manner that the path of the laser beam is not affected. However, such machines are bulky and occupy a lot of space, which makes the maintenance of such machines difficult.
SUMMARY:
The subject matter described herein is directed to a gemstone processing machine. In particular, the subject matter relates to a gemstone processing machine. The gemstone processing machine includes a laser source for generating a laser beam for generating a laser beam. A first reflective member is provided on a first side of the laser source for completely reflecting the laser beam. A pair of beam benders is provided on the other side of the laser source for diverting the laser beam from a straight path. Preferably, the beam benders are positioned in such a manner that the laser beam follows a U-shaped path. The laser beam, diverted from the beam benders, is partially reflected by a second reflective member. The second reflective member allows a partial laser beam to pass through it for performing the desired processing.
By providing beam benders in the gemstone processing machine, the need for a long rail is eliminated, thereby reducing the material and cost of the gemstone processing machine as well as the space.
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These and other features, aspects, and advantages of the present subject matter will become better understood with reference to the following description and appended claims. This summary is provided to introduce a selection of concepts in a simplified form. 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.
BRIEF DESCRIPTION OF THE DRAWINGS:
The above and other features, aspects and advantages of the subject matter will be better understood with regard to the following description, appended claims, and accompanying drawings where:
Fig. la illustrates a top view of a gemstone processing machine in accordance with one embodiment of the present subject matter.
Fig. lb illustrates a side view of a gemstone processing machine of Fig. la depicting various components mounted on a rail.
DETAILED DESCRIPTION:
Described herein is a gemstone processing machine that is compact and efficient to performing various operations on a gemstone. For example and by no way limiting the scope of the present subject matter, the gemstone processing machine is a gemstone processing machine. The gemstone processing machine of the present subject matter includes a pair of beam benders for diverting a laser beam from a straight path. The laser beam in the present subject matter follows a U-shaped path, thereby eliminating the need for a long rail to accommodate various components of the gemstone processing machine.
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Fig. la illustrates atop view of a gemstone processing machine 100 in accordance with one embodiment of the present subject matter. The gemstone processing machine 100 of the present embodiment includes a plurality of components. For example the gemstone processing machine 100 includes a laser source 102, a front mirror 104, a rear mirror 106, a pair of apertures 108 and 110, a Q-switch 112, an expander 114, a polarizer 116, a pair of beam benders 118 and 120, a rail 122, and an operating assembly 124. Fig. lb illustrates a side view of the gemstone processing machine depicting various components mounted on the rail 122.
In one preferred embodiment, the rear minor 106, the rear aperture 110, and the Q-switch 112 are placed on one side of the laser source 102 whereas other components like polarizer 116, the front aperture 108, the front mirror 104, and the operating assembly 124 are placed offset from the laser source 102.
The laser source 102 generates a laser beam 126 that is to be used for processing a diamond stone (not shown in the figures). The rear mirror 106, also referred to as a first reflective member hereinafter, is disposed on a first side of the laser source 102. The rear mirror 106 receives the laser beam 126 coming from the laser source 102 and is fully reflective i.e. it completely reflects the laser beam 126. The Q-switch 112 and the rear aperture 110 are positioned between the laser source 102 and the rear mirror 106. The Q-switch 112 is a device that produces a pulsed laser output by alternately blocking and unblocking the path of reflection of laser beam 126 between two mirrors. In other words, the Q-switch 112 stores the laser beam 126 and emits as a burst of high peak power. The aperture 110 controls the light amplification and provides the sharp frequency band i.e. the aperture restricts the path of reflection between the two mirrors 104 and 106.
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The laser beam 126 of the present subject matter follows a curved path in the gemstone processing machine 100. A pair of beam benders 118 and 120 is provided on the second side of the laser source 102 to divert the laser beam 126 from the straight path. In one preferred embodiment, the beam benders 118 and 120 are reflective mirrors. In the present embodiment of the present subject matter, the laser follows a U-shaped path while passing from the-laser source 102 to the polarizer 116.
Owing to the fact that the path of the laser beam 126 is U-shaped, the components of the gemstone processing machine 100 can be placed adjacent to each other, thereby making the machine compact i.e. the requirement of a long rail is eliminated. This facilitates reduction in material and space. As a consequence, there is a reduction in cost of the gemstone processing machine 100 and the robustness of the gemstone processing machine 100 increases.
The polarizer 116 converts the mixed polarization laser beam 126 into a single polarization beam. The polarized laser beam 126 from the polarizer 116 is directed to the front mirror 104, also referred to as a second reflective member hereinafter. The front mirror 104 is a partially reflective mirror i.e. the front mirror 104 allows only a partial laser beam 126 to pass through it.
The laser beam from the partially reflective front mirror 104 is then directed to the operating assembly 124 through the expander 114 for processing the diamond stone.
The operating assembly 124 includes a safety shutter that blocks the path of the laser beam 126. The safety shutter is a mechanical device that closes and blocks the laser beam 126 in case of any electronic failure in the gemstone processing machine 100.
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The operating assembly 124 includes a plurality of components for processing the diamond stone with the help of the laser beam 126. For example, the operating assembly 124 and 126 includes a beam diverting member 128, a focal lens, and a camera 130. The beam diverting member 128 diverts the laser beam 126 at 90 degrees to direct the laser beam towards the diamond stone placed on a fixture. The diverted laser beam 126 is focused onto the diamond stone by means of the focal lens. The focal length of the focal lens can be changed to alter the power density and depth of the laser beam 126. The camera 130 is used to monitor and record the movement of the diamond stone during processing.
The gemstone processing machine as described above can be used for gemstone sawing, gemstone bruting and for other gemstone processing techniques.
A CNC interface is used to actuate the gemstone processing machine 100. The inputs provided in the CNC interface decides the motion of the fixture and hence the movement of the diamond stone during processing.
The gemstone processing machine of the present subject matter has many advantages, including those mentioned below. The gemstone processing machine is made compact and is economical due to the reduction in the material of the long rail used for supporting various components for performing diamond processing. Further, the maintenance of the gemstone processing machine is easy due to the compactness of the machine.
Although the subject matter has been described in considerable detail with reference to certain preferred embodiments thereof, other embodiments are also possible.
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As such, the spirit and scope of the appended claims should not be limited to the description of the preferred embodiment contained therein. Dated this 01 day of August 2008

T. SRINIVASAN
AGENT FOR THE APPLICANT To
The Controller of Patents The Patent office at Mumbai
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