Title of Invention

AN IMPROVED QUARTZ TUBE LAMP FOR INDUSTRIAL AND LABORATORY HEATING AND TESTING APPLICATIONS

Abstract The present invention discloses an improved quartz tube lamp for industrial and laboratory heating, curing and lighting applications which comprises a quartz tube having an elongate mainbody portion which accommodates a radiating filament, and bend portions at substantial end sections of the main body portion. The radiating components such as filament and its supporting components are accommodated within the mainbody portion, and the non-radiating components such as filament leg, seals and accessories for electrical connection to filament are accommodated within the bend portion. The bend portions make an angle of about 90 degrees with the axis of the tube, thereby making the radiating length equal to the total length of the lamp and also enable protecting the non-radiating components from potential radiation damage from the filament.
Full Text FORM 2
THE PATENTS ACT, 1970 (39 of 1970)
COMPLETE SPECIFICATION [See section 10]
AN IMPROVED QUARTZ TUBE LAMP FOR INDUSTRIAL AND LABORATORY HEATING AND TESTING APPLICATIONS

ORGN
1331-MUM-2003
30-12-2003

THE FOLLOWING SPECIFICATION
PARTICULARLY DESCRIBES THE
NATURE OF THIS INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFOMED.

GRANTED
13-5-2004

TITLE
AN IMPROVED QUARTZ TUBE LAMP FOR INDUSTRIAL AND LABORATORY HEATING AND TESTING APPLICATIONS
FIELD OF INVENTION
The present invention relates to the field of quartz tube lamps especially those used for lighting, heating and curing purposes in various industrial and laboratory high power, high temperature testing and heating applications. The present invention may also be applicable for twin tube lamps, coated lamps and such lamps commonly known as emitter, quartz tube, quartz heater, heater lamp etc.
BACKGROUND ART
Typically, a conventional quartz tube lamp comprises the following features and associated functions therewith.
Referring to the drawings and particularly to Fig. 1, a conventional quartz tube lamp comprises an elongate tube (102) preferably made of quartz or any other material which would be clear and transparent to heat radiation, accommodating therein, an elongate filament (101) preferably made of coiled tungsten or carbon as a radiation heat source. A plurality of supports (103) may be disposed either at equal intervals or at convenient spacing so as to hold the filament (101) in non-contact relationship with the inner surface of the tube (102). The tube (102) is normally sealed at the ends by hermetic seals (105) and then filled with gas such as argon-nitrogen in

precise amount with appropriate amount of halogen through an exhaust tube, which is finally removed and sealed forming an exhaust tip (109). The gas system inside prevents blackening of conduit wall, oxidation of filament and arcing phenomenon. A pair of legs (104) which extend individually from the ends of the filament (101) carry current to the filament (101) from a power source (not illustrated). The legs (104) are welded on a moly ribbon and becomes a part of the hermetic seals (105), with a ceramic cap (106) fitted over the seal. The other end of ceramic cap carries the lead wire (107) having a lug (108) for the purpose of a convenient conection.
Fig.2 illustrates a bank of heating filaments of conventional quartz tube lamps, comprising a large reflector (501), with individual lamps comprising the aforesaid configuration.
During the normal course of functioning of the quartz tube (102), the filament (101) temperature may rise to as high as 2200 °C. while that of transparent tube (102) may rise to as high as 600 °C.
From the foregoing description of the prior art, it will become apparent that the conventional quartz tube lamp has a radiating length which is essentially equal to effective length of the filament, much shorter than the total length of the lamp while end portion i.e. from leg to the end connection wire which is designated as (B) in Fig 1 remains non radiating portion and hence forms in¬effective length at both ends of the lamp.
Referring to Fig. 3 which shows a graph illustrating the radiation flux distribution v/s length of heating zone, when the lamp is used in a linear array, it is apparent that the part (A) of the lamp radiates to full intensity

while at the part (B+B) between two adjacent lamps, the intensity of radiation falls to zero.
It can be clearly seen that radiation flux distribution shows gaps of zero value along the length of heating zone.
Maximum intensity that can be obtained with the prior art lamp has serious limitations. This is because considering Fig.1, for a standard lamp of 300 mm length, assuming the length of part (B) at each end being minimum 50 mm, the effective length useful for radiation remains at only 200 mm i.e. approximately 60% of the lamp length.
Referring back to Fig 2, the reflector (501) is substantially broader than the effective length of the heating lamp. At high intensity of radiation, the reflectors of high efficiency have to be used. Since the reflectors are normally gold plated, substantial cost is added to the construction of the lamp fixture.
Eventhough only two elementary arrangements of the quartz tube have been discussed above, in applications where a group of lamps are closely packed on a panel, the surface area of the panel required is much larger than the effecting heating area.
Furthermore, the lamp connecting components, seal, ceramic cap, lead wire and lug requires cooling when used in high intensity heating device as they are directly exposed to radiation. If seal temperature exceeds 350 deg C, the metallic ribbon in the seal portion oxidizes and causes lamp failure. To avoid lamp failure due to radiation exposure of seal portion, expensive cooling means such as compressed air flow or covering the part with

reflector therefore becomes essential.
By dint of determined research and intuitive knowledge, our inventor has proposed an improved quartz tube lamp wherein the proposed quartz tube lamp overcomes the deficiencies and effectively finds solutions to the problems associated with the prior art by having a bend portion in the quartz tube substantially at right angle to the axis of the tube, from the beginning of the in-effective or otherwise termed non-radiating length, thereby surprisingly achieving substantial space, material and cost savings.
OBJECTS OF THE INVENTION
Accordingly, the objects and advantages of the present invention are set out herein below:
An object of the present invention is to provide an improved space saving quartz tube lamp wherein the lamp offers uniform energy distribution along the exposed length.
An object of the present invention is to provide an improved space saving quartz tube lamp wherein the non-radiating length of quartz tube is substantially minimized and the non-radiating components such as filament leg, seal, cap and conducting wires are protected from potential radiation damage and hence lamp failure.
An object of the present invention is to provide an improved space saving quartz tube lamp wherein in applications where group of lamps are closely packed, the surface area of the lamp is substantially reduced thereby resulting in maximum saving of space, material and cost of the lamp fixture.

An object of the present invention is to provide an improved space saving quartz tube lamp wherein in applications where group of lamps are closely packed, modular arrangement of very high density panels could be made possible to suit special configurations.
SUMMARY OF THE INVENTION
The present invention discloses an improved quartz tube lamp which comprises a quartz tube having an elongate mainbody portion which accommodates a radiating filament, and bend portions at substantial end sections of the mainbody portion. Broadly speaking, the invention proposes to accommodate the radiating components such as filament and its supporting components within the mainbody portion, and the non-radiating components such as filament leg, seals and accessories for electrical connection to filament within the bend portion. The bend portions make an angle of about 90 degrees with the axis of the tube, thereby making the radiating length equal to the total length of the lamp and also enable protecting the non-radiating components from potential radiation damage from the filament.
BRIEF DESCRIPTION OF DRAWINGS
To complement the description that is being given and in order to promote a better understanding of the characteristics of the invention in accordance with a practical embodiment of the same and as an integral part of the said description a set of drawings accompany it in which, in an illustrative and non-restrictive way, the following are represented :-
Fig. 1 is the elevation of the conventional quartz tube lamp.

Fig. 2 is the schematic arrangement of a bank of conventional quartz tube lamps.
Fig. 3 is graph depicting the variation of heat flux along the length of a conventional quartz tube lamp.
Fig. 4 is the front view of the quartz tube lamp proposed by the present invention.
Fig. 5 is the plan view of the arrangement of a bank of quartz lamp according to the present invention.
Fig 6 is a graph depicting the variation of heat flux along the length of the quartz tube lamp in accordance with the present invention.
Fig 7 is the elevation of the quartz tube lamp with a modified orientation of exhaust tip according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS THEREOF
The present invention relates to an improvement in quartz tube lamps especially those used in industrial and laboratory high power, high temperature testing and heating applications.
In this application, the term quartz tube lamp is used herein for the purposes of illustration only. It is not to be construed that the lamp described herein refers to those made of quartz oniy. The teachings of this invention may also be applicable to lamps made of material such as translucent quartz, ruby and hard glass.

Referring to Fig 4, and in the embodiment shown, the quartz tube lamp in accordance with the present invention comprises an elongate tube (302) made of a material preferably of transparent, temperature resistant material such as quartz, translucent quartz, ruby and hard glass.
In accordance with one aspect of the present invention, the quartz tube (302) may preferably have a circular cross section. This invention also contemplates other exemplary embodiments of the quartz tube (302) which may include cross sections such as twin tube, and other geometric shapes which when however functions substantially in the same way to achieve substantially similar result, is deemed to be within the scope of this invention.
The quartz tube (302) in accordance with the present invention comprises an elongate mainbody portion (302a) and a bend portion (310) substantially at each end section of the mainbody portion as best illustrated in view B of Fig 4. The bend portions (310) preferably make an angle of about 45 degrees to 135 degrees relative to the axis of the mainbody portion (302a).
The mainbody portion (302a) accommodates a filament (301) preferably made of a material such as coiled tungsten, nichrome and carbon as a radiation heat source. A plurality of supports (303) may be disposed in the mainbody portion (302c) to hold the filament (301) in non-contact state with the inner surface of the quartz tube (302). The supports (303) may be arranged to hold the filament (301) without sagging.
The operation temperature of the filament (301) may preferably in the range of 1400 deg Celsius to 2500 deg. Celsius.

In accordance with the present invention, the bend portions (310) on either end sections of the mainbody portion (302a), originate substantially at the starting and end portions of the radiating length of the filament (301).
For the purposes of this invention, the radiating length of the filament is defined as (by) the coiled, straight and other configured winding of filament which is at a much higher temperature than the surrounding (usually above 650 degrees Celsius).
Accordingly, referring to view A of Fig 4, the bend portions (310) individually accommodate at least one non-radiating component such as a leg (304) for conducting current from a power source (not shown) to the filament (301). The free end (305) of each bend portion (310) has a pinched seal (hermetical seal) configuration into which a ceramic cap (306) housing a conducting wire (307) is fitted. The conducting wire (307) is connected to the filament leg (304) at one end and to an external electrical lug (308) at the other end for external connection to a power source.
The tube (302) may be preferably filled with gas such as an appropriate blend of halogen, argon, nitrogen mix to prevent blackening of tube walls, oxidization of filament and to prevent arcing phenomenon.
A provision preferably an exhaust tube (not shown) is provided for filling the gas. The exhaust tube is tipped off (sealed) subsequently. Preferably, the exhaust tip (309) is oriented on the tube surface above the axis of the tube as shown in Fig 4.
Alternatively, the exhaust tip (609) may also be formed on the surface of the tube below the axis of the tube as shown in Fig7.

Fig 5 illustrates a bank of quartz tube lamps (5B01, 5B02) mounted onto a common panel (5B03).
Referring to Fig 6, the array of quartz tube lamps in accordance with the present invention provides a substantially uniform radiation flux distribution as the effective radiation length of the array is substantially equal to the total length of the array.
Thus the present invention proposes a quartz tube lamp configuration wherein the radiating length is substantially equal to the total length of the lamp and the non-radiating components such as filament leg, seal etc., are protected from potential radiation heat damage as such components are accommodated in the bend portion which is substantially oriented at right angles to the axis of the tube.
Thus the invention proposes a quartz tube lamp which saves space, material and cost of manufacture.
The present invention is applicable for various linear construction quartz tube lamps of various lighted lengths, voltages, wattage etc.
The present invention may also be applicable to twin tube lamps, coated lamps, and translucent lamps of different filament materials of similar construction with or without seals.
Thus, while there have been shown and described and pointed out fundamental novel features of the present invention as applied to preferred embodiments thereof, it will be understood that various omissions and substitutions and changes in the form and details of the device described

may be made by those skilled in the art without departing from the spirit of the present invention. For example, it is expressly intended that all combinations of those elements which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Substitutions of elements from one described embodiment to another are also fully intended and contemplated. It is possible to introduce variations, in the whole or its parts, in the shape, materials and disposal, provided that said variations do not substantially alter the characteristics of the invention that are indicated by claims appended hereto.

I CLAIM
1. A quartz tube lamp for industrial and laboratory heating and testing
applications comprising :
(i). an elongate mainbody portion accommodating a radiating filament therein;
(ii). a bend portion disposed substantially at end sections of said mainbody portion wherein:
said bend portion is oriented at predetermined angle relative to mainbody portion, and accommodates atleast one non-radiating component associated with the radiating filament whereby the radiating length of the lamp is substantially equal to the total length of the lamp.
2. The quartz tube lamp according to claim 1, wherein the filament is made of coiled tungsten or carbon material.
3. The quartz tube lamp according to claim 1 or 2, wherein the bend portions originate at the end of radiating length of the lamp.
4. The quartz tube lamp according to any one of claims 1 to 3, wherein the bend portion makes an angle in the range of 45 degree to 135degree with the mainbody portion.
Dated this 30th day of December, 2003.
FOR MAHENDRA KANTILAL SHAH By His Agent

(MANISH SAURASTRl) KRISHNA & SAURASTRI

Documents:

1331-mum-2003-abstract(13-5-2004).doc

1331-mum-2003-abstract(13-5-2004).pdf

1331-mum-2003-claim(13-5-2004).doc

1331-mum-2003-claim(granted)-(13-5-2004).pdf

1331-mum-2003-correspondence(13-5-2004).pdf

1331-mum-2003-correspondence(ipo)-(14-6-2007).pdf

1331-mum-2003-drawing(13-5-2004).pdf

1331-mum-2003-form 1(30-12-2003).pdf

1331-mum-2003-form 19(30-12-2003).pdf

1331-mum-2003-form 2(granted)-(13-5-2004).doc

1331-mum-2003-form 2(granted)-(13-5-2004).pdf

1331-mum-2003-form 3(12-5-2004).pdf

1331-mum-2003-form 3(30-12-2003).pdf

1331-mum-2003-form 5(30-12-2003).pdf

1331-mum-2003-power of attorney(19-12-2003).pdf

abstract1.jpg


Patent Number 207584
Indian Patent Application Number 1331/MUM/2003
PG Journal Number 32/2007
Publication Date 10-Aug-2007
Grant Date 14-Jun-2007
Date of Filing 30-Dec-2003
Name of Patentee MAHENDRA KANTILAL SHAH
Applicant Address 2A, SHREE VALLABH APTS., 11/2, BOAT CLUB, PUNE -411 001.
Inventors:
# Inventor's Name Inventor's Address
1 MAHENDRA KANTILAL SHAH 2A, SHREE VALLABH APTS., 11/2, BOAT CLUB, PUNE -411 001.
2 SHARSHCHANDRA VISHWANATH RAJARSHI 184, A-2 KASBA PETH, PUNE 411 011. MAHARASHTRA,INDIA.
PCT International Classification Number H05B 35/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA