JPS6297254A - Welding lamp for a plurality of levels - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates generally to tubular incandescent lamps, and more particularly to incandescent lamps as applied in heating or copying processes.

BACKGROUND OF THE INVENTION Copying machines typically use two different types of lamps. One is called an exposure lamp, and the other is called a welding lamp. Exposure lamps are intended purely for the purpose of emitting light during the exposure phase of operation. On the other hand, a fusing lamp is used primarily to heat to fix toner used in a copying machine. Although the principles of the present invention apply primarily in connection with fusing lamps, they are also applicable to other general heating purposes.

Fuser lamps typically have a single filament configuration and have a length that corresponds to the largest dimension (length) of the paper that is to be copied. Certain infrared lamps in particular
It uses two filaments arranged in parallel and electrically connected in parallel within a quartz envelope, allowing significantly higher operating wattages to be obtained by energizing both filaments simultaneously. (U.S. Patent No. 3.4
43,144). According to this patent, the use of parallel filaments provides a higher heating density per unit area of the envelope wall.

The lamp of this US patent, as described, does not allow selective energization of these filaments (i.e., dual-level welding) to adjust to different increasing wattage output requirements.

Additionally, the lamp includes a series of spacers placed along the length of the filaments to prevent them from drooping into the quartz envelope, but to prevent short circuits. There is no way to isolate them from each other.

PROBLEM TO BE SOLVED BY THE INVENTION In some copier applications, it is desirable to be able to utilize different levels of energy to deposit (i.e., deposit) toner onto a copy of an original document. A high level of energy is desired when the welding system begins to make the first copy as it cools down. Typically, some time is required to bring the fusing system up to operating temperature, which can limit the rate at which the first copy can be delivered, which is used in the evaluation of copiers. It serves as one measurement standard. U.S. Patent No. 4.442
．． No. 374, in order to fix the toner equally on both the short paper and the long paper, i.e. so that the energy per square meter of paper is the same for both the short paper and the long paper. Dual length filament incandescent lamps are typically provided that allow for the welding of two different lengths with a predetermined amount of energy per length. This results in two levels of total lamp energy, but only one level of welding energy per length of paper.

It is therefore clear that a tubular incandescent lamp that provides multiple levels of energy for use in heating and is more compact and easier to manufacture would represent an important advance in this field of technology.

OBJECTS OF THE INVENTION The main object of the invention is therefore to improve the technology of tubular incandescent lamps, in particular to improve the technology of tubular incandescent lamps, including lamps with more than one filament.

Another object of the invention is to provide an improved incandescent lamp that is easy to use in devices requiring multiple levels of energy for heating.

Still another object of the invention is to provide an improved incandescent lamp that is compact, inexpensive and can be manufactured in mass production.

SUMMARY OF THE INVENTION According to one aspect of the invention, there is provided a tubular quartz envelope having first and second pressure-sealed ends; A tungsten-halogen incandescent lamp is provided that includes a pair of coiled tungsten filaments extending in the direction and a fill gas mixture enclosed within the envelope. The lamp further includes a first contact means associated with the first pressure seal end and electrically coupled to the first end of each filament; a second contact means associated with and electrically coupled to the second end of the one filament; and an uncoupled second end of the one filament associated with said second pressure sealing end; a third contact means electrically coupled to the first and second contact means, the filament being energized when a predetermined voltage is applied between the first and second contact means; It is also energized when a predetermined voltage is applied between the third contact means. Additionally, the lamp includes means for electrically isolating each filament, the electrically isolating means being disposed within the envelope and extending longitudinally inside the envelope.

[Embodiments] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

With particular reference to FIG. 1, a lamp 10 is illustrated that includes first and second pressure seal ends 14.
and 16, respectively. Ends 14 and 16 are connected to envelope 12
and are formed by using pressurized operations and equipment known in the art.

Envelope 12 should preferably be made of a material with a high melting point, such as fused silica or quartz.

The lamp 10 is of the tungsten-halogen type and thus has a fill gas mixture comprising an inert gas and a halogen or halide. In the present invention, the lamp is filled with about 1 atmosphere of argon (as an inert gas) and has about 200 micrograms of bromine (specifically methyl bromide). The components of the filling mentioned above are merely illustrative of what the filling gas mixture usually consists of, and are not intended to limit the invention. Lamp 10 further includes a pair of tungsten filaments 18 and 20 disposed within envelope 12 and extending longitudinally within the envelope.

Conventional lamps, particularly the lamp of U.S. Pat. No. 3,443,144M, typically include means for spacing or supporting the filament to prevent it from contacting the envelope wall. The use of such spacing or support means has the disadvantage that it is difficult to insert them into mass-produced lamp envelopes and that short circuits occur due to insufficient electrical isolation between the filaments. There are drawbacks that can occur. Therefore, the present invention uniquely provides a means of electrically isolating the filament;
Additionally, it promotes compactness of the lamp and simplifies lamp assembly.

In accordance with the teachings of the present invention, filaments 18 and 20 are electrically insulated from each other by isolation means consisting of two tubes 22 and 24 longitudinally disposed within envelope 12, as illustrated in FIG. Isolated. The filaments 18 and 20 extend longitudinally through tubes 22 and 24, respectively. The tubes 22 and 24 should be made of an electrically insulating material that is transparent and has a high melting point, such as quartz. Tubes 22 and 2
4 extends within envelope 12 to a location approximately one millimeter (mm) inward from pressure seal ends 14 and 16. The filaments can probably be sufficiently electrically isolated by using a tube around one of the filaments. The filament is hermetically sealed within pressure sealed ends 14 and 16.

A plurality of support members 26 (illustrated in FIG. 1) support filaments 18, 20 at preselected points along the length of filaments 18, 20 (approximately 25.1 nn+ spacing). Each support member 26 is made of a coil member, one end of which is connected to each of the filaments 18 and 2.
0 (and therefore fixed), and the other end (which has a larger diameter than the above one end) is connected to the tube body 2'2.
and 24, respectively.

In the embodiment shown in Figure 1, filaments 18 and 20 have a total length of approximately 350 mm. In addition, the envelope 12
is a T-5 quartz tube with an outer diameter of about 15 mm and a thickness of about 1 mm. The tubes 22 and 24 have an outer diameter of about 61 mm and a thickness of about 1 mm.
It is an m+n T-2 quartz tube.

Ceramic base or end caps 28 and 30 are preferably used to facilitate positioning of lamp 10 within a reproduction machine designed to use it. It is therefore only necessary in each copying machine to provide some means for receiving this part. As can be seen, such means may be of relatively simple design. The ceramic bases 28 and 3o preferably have a substantially cylindrical shape and include slots into which the flat pressure seal ends 14 and 16 are designed to be inserted.

Filaments 18 and 20 are energized by means for applying a predetermined voltage between contact means located within the pressure sealed end of lamp 10. In particular, the first contact means 32 is associated with the end 14 and - the force tube 2
contact means 34 and third contact means 36 are associated with end 16 .

The first contact means 32 is arranged outwardly from the end 14 at the bittern end 1 .
a first lead-in conductor 32a extending inwardly within the end 1;
4 and electrically coupled to both the first lead-in conductor 32a and the first ends 18a and 20a of filaments 18 and 20, respectively. The second contact means 34 includes a second lead-in conductor 34a extending outwardly from the end 16 and inwardly within the end 16, and a second lead-in conductor 34a disposed within the end 16 and extending inwardly within the end 16.
4a and a foil portion 34b electrically coupled to both the second end 18b of the filament 18. Finally, the third contact means 36 includes a third lead-in conductor 36a extending outwardly from the end 16 and inwardly within the end 16.
and a foil portion 36b disposed within the end 16 and electrically coupled to both the third lead-in conductor 36a and the unconnected second end 20b of the filament 20.

Introductory conductor 32 is coupled to lead A, which is coupled to a common terminal of power supply 38. Lead conductors 34 and 36 are coupled to leads B and C, respectively, while leads B and C are connected to a control switch 40 coupled to power supply 38.
is combined with

Leads A, B, and C are 16AWG (American Wire Gauge) Teflon insulated stranded wire rated for 600 volts and 200°C.

Leads B and C are adapted to supply voltage across filaments 18 and 20 separately or simultaneously via switch 40. Filaments 18 and 20 may be of varying wattage, but the total wattage output of both filaments 18 and 20 must be greater than either alone. In one embodiment of the invention, filament 18 has a rating of approximately 375 watts (120 volts) and filament 20
has a rating of approximately 1250 watts (12o volts).

The total possible wattage output in lamp 10 is therefore:
It becomes 1625 watts. The total length of lamp 10 is approximately 420m
It is m.

Referring to FIGS. 2A-2C, a lamp 5o constructed in accordance with the teachings of the present invention is illustrated. lamp 1
The members of the lamp 5o that are common to the members of the lamp 5o are given the same numbers, and a detailed explanation of these members will be omitted here as it is deemed unnecessary (see FIG. 2A). Lamp 50 has an envelope 52 that includes filament 18.
It includes isolation means 54 extending longitudinally through the envelope for isolating the filament 20 from the filament 20. The isolation means 54 consists of an insulating partition member (see FIG. 2B) that forms two chambers within the envelope 52. In the lamp 5o, the isolation means 54 is structurally connected to the - extending to the pressure sealing ends 14 and 16 (partially illustrated in FIG. 2C).As shown in FIGS. 2A and 2B, the isolation means 5
4 has a substantially flat shape and has ends 14 and 1
Two chambers are formed within the envelope 52 which is sealed at 6.

In lamp 50, envelope 52 and isolation means 54 are formed from quartz and can be formed in a single manufacturing step, for example by forming a quartz tube with two holes or chambers. As seen in FIGS. 2B and 2C, the quartz tube (i.e., envelope 52) may be elliptical with two dome-shaped chambers inside. In the lamp 50 of this embodiment (see FIG. 2B), the quartz tube has an outer diameter of about 15 mm and an inner diameter d of about 13+ mm.
It is nm. The isolation means 54 has a length L of approximately 11 mm, and the diameter of each chamber is approximately 6 mm. Isolation means 5 for lamp 50
4 need not be part of the envelope 52, it merely needs to be an insert providing similar functionality as described above. Thus, the present invention uniquely provides a means for increasing the compactness of the lamp and simplifying lamp assembly while further isolating the filament.

Lamp 50 is similar to lamp 10 with respect to filament length and wattage, fill gas mixture, overall lamp length, lead connections, and lamp to circuit wiring. Lamps 10 and 50 are primarily infrared heating lamps for use in copying machines, but are not limited to use in copying machines. These lamps provide multiple levels of welding energy per square centimeter (cm2) of paper depending on the requirements arising from the particular application, regardless of design length, without unnecessarily complicating lamp production. Currently, the filament length may be designed to be a fixed length as required for a particular application, but the energy per square centimeter of paper can be varied by energizing either filament separately or simultaneously. Variable means are provided for providing at least three levels of welding energy in total and per square meter of paper.

ADVANTAGES OF THE INVENTION Infrared lamps made according to the teachings of the present invention have the advantage of greatly increasing the speed of copier fusing systems in obtaining start-up temperatures. For example, using the wattages listed above for lamps 10 and 50, at start up 1625
Watt's energy (when both filaments are energized)
is supplied to the welding system. The energy required immediately (after about 1 or 2 photocopies) is 125
It changes to 0 watts (energizing only one filament) and then to 375 watts (energizing only the other filament), which continues to provide enough energy to properly adhere the toner to the paper. Become. Some welding systems may be used to weld higher wattage filaments, and filament switching can be controlled by a thermostat that can switch between different wattage filaments as required.

Although what is presently considered to be the preferred embodiment of the invention has been illustrated and described, it will be apparent to those skilled in the art that various modifications and changes can be made without departing from the scope of the invention. .

[Brief explanation of drawings]

FIG. 1 is a partially sectional side view showing one embodiment of the present invention and a related electric circuit, and FIGS. 2A to 2C are partially sectional side views and sectional views showing other embodiments of the present invention. , and a partial perspective view. 10: Lamp 12: Tubular envelope 14. 16: Pressure-sealed end 18. 20: Filament 22. 24: Tube 26: Support member 32: First contact means 34: Second contact means 36: First 3. Contact means 38: Power source 40: Control switch 50: Lamp 52: Envelope 54: Isolation means procedural amendment (method) November 21, 1985 Commissioner of the Japan Patent Office Black 1) Display of Akio Tono case 1988 Year: Patent Application No. 190678 Title of Invention Person who corrects multi-level welding lamps

Claims (13)

[Claims] (1) a tubular quartz envelope having first and second pressure-sealed ends; and first and second coiled tungsten filaments extending longitudinally within the tubular envelope; , a fill gas mixture inserted into said envelope; and said first
a first contact means associated with a pressure-sealed end of and electrically coupled to a first end of each of said first and second filaments; and said second pressure-sealed end; a second contact means associated with and electrically coupled to the second end of the first filament; and a second contact means associated with the second pressure seal end and electrically coupled to the second end of the second filament. third contact means electrically coupled to the ends; and third contact means disposed within the envelope and extending longitudinally within the envelope for electrically connecting the first and second filaments. isolating means for isolating the contact means, the first filament being energized when a predetermined voltage is applied between the first and second contact means, and the second filament A tungsten-halogen incandescent lamp characterized in that it is energized upon application of a predetermined voltage between the first and third contact means. (2) The filament is energized simultaneously when a predetermined voltage is applied between the first and second contact means and between the first and third contact means. The lamp described in item 1. (3) a first lead-in conductor, wherein said first contact means extends outwardly from said first pressure sealing end and inwardly within said first pressure sealing end; 3. A lamp according to claim 2, further comprising a foil portion located at and electrically coupled to said first lead-in conductor and said first end of each of said filaments. (4) a second lead-in conductor, wherein said second contact means extends outwardly from said second pressure sealing end and inwardly within said second pressure sealing end; and said second lead-in conductor and said first filament.
4. A lamp according to claim 3, comprising a foil portion electrically connected to an end of the lamp. (5) a third lead-in conductor, wherein said third contact means extends outwardly from said second pressure sealing end and inwardly within said second pressure sealing end; and the second conductor of the third lead-in conductor and the second filament.
5. A lamp according to claim 4, comprising a foil portion electrically connected to an end of the lamp. 6. The lamp of claim 5, wherein said isolation means is made of an electrically insulating material. (7) The isolation means includes at least one quartz tube longitudinally disposed within the envelope, and one of the filaments extends longitudinally into the quartz tube. Lamps according to scope 6. (8) The isolation means includes two quartz tubes disposed longitudinally within the envelope, and one of the filaments extends longitudinally into each quartz tube. The lamp according to item 6 in the range of . (9) The isolation means includes an insulating partition member, the partition member extending longitudinally within the envelope and forming at least two chambers within the envelope. The lamp described in item 6. (10) The lamp according to claim 9, wherein the partition member is structurally a part of the envelope. (11) the partition member has a substantially flat shape;
and 2 in the envelope sealed at the sealed end.
11. A lamp according to claim 10 forming two chambers. 12. The lamp of claim 11, wherein said substantially flat-shaped partition member is formed from quartz. (13) The lamp of claim 6, wherein said lamp is an infrared heating lamp for use in a copying machine.