FR2620266A1 - Tubular fluorescent bulb with tubular stem and standardised base - Google Patents

Abstract

The invention relates to a low-pressure fluorescent light bulb, of cylindrical tubular shape and including a tubular stem with two stages of electrodes. It consists of a cylindrical envelope 1, gauged 2, including a round bottom 3 at one end and a diametral narrowing 4 at the other. To the latter is welded 5 a tubular stem 6. After this, the assembly is lowered into a standardised base 7 as far as the beginning of the straight portion 8 of the envelope. The skirt 9 of the base therefore allows the lowering, masking and sealing 10 of the narrowing, rendering the base integral with the bulb. The bulb according to the invention is particularly intended for connection to the mains.

Description

 Tubular fluorescent bulb with tubular base, with standardized base.

 The present invention relates to the production of a low pressure fluorescent light bulb, of tubular shape, which is obtained by welding a cylindrical envelope on a tubular leg. said weld being masked by the skirt of the standard base and maintained by it.

 It is known to weld electrodes on the wall of envelopes to make them discharge chambers.

 In these embodiments, there is therefore no stand for electrodes.

 Concerning a particular mounting of a foot with two stages of electrodes, on long tubular envelopes for luminescent lamps, two Japanese patents known under the numbers 49-35796 and 55-155461 show us feet carrying electrodes, but these feet are pinched, er V shape, and are not tubular in the sense defined in French patent application i 87 08486.

the welding of these pinched feet to the envelope of the lamp is carried out directly therefrom, directly on the right part forming a discharge enclosure
In addition, the assembly thus formed by the welding of the envelope and the foot is not lowered or fixed in bases of the standardized type, genus Goliath, dison, - c2 and
E 14 and others
In addition, it is very unlikely that they could descend into the said caps, see other specials with straight skirts, given the significant dimensional variations of the tubes, which are not taken up by any play and on the other hand, those caused by the welds on the chambers or envelopes having sufficiently large diameters to correspond to a discharge tube.

 Indeed, during the fusion of the flange of the foot for the welding in one go, only possible here, this one would not leave any nodules and thickenings.

 This type of welding, called by a person skilled in the art "all at once", is the only one that can be envisaged in this embodiment, this in order not to overheat the tube, to deform or deteriorate the powdering, to lengthen the solidification time and considerably increase the internal tensions for a glass which can no longer be annealed, that is to say increase the risks of breakage by surface rupture, and of local embrittlement.

 The use of a flat charcoal graphite of external compression of the molten glass, would cause on this type of very thin glass with rapid solidification, more important complications.

 It is difficult to see in these conditions, the possibility of completely descending such tubular envelopes welded to feet, in particular or standard caps at the risk of a significant waste in the final assembly of said tubes in the caps.

The problem is therefore not resolved
The cost price of these said bulbs is then very random and problematic
The bulb according to the invention, composed of a cylindrical tubular envelope (1) is welded in a constriction (4) to a tubular leg (6) already mentioned, and the assembly thus formed is lowered (9) to the start of the right part of the envelope (8) in a standardized base (7).

 This has the consequence that by using tubular casings, the outside diameters of which correspond substantially to the inside diameters of the caps, at the level of the skirt, allied with shrinking foot welds (5), it is possible to easily and completely descend and hide this solder in the base and thereby maintain said envelope in a standardized base.

The luminescent envelope is not altered by this assembly, and by the diameters used, there is a linear continuity between the base and the envelope
In addition, the powdered wall (11), therefore opaque, has a uniform appearance extending from one end to the other of the bulb, over its entire length.

 The benefits are considerable, both industrially and economically.

 The realization with tubular fluorescent bulbs has now become simpler, more reliable, less expensive, easier, this, by the use of cylindrical tubes on the one hand, of standardized bases on the other hand, and by a particular type foot-in-weld welding machine.

 the feet used according to the invention, being with two stages of electrodes, this means that the same foot carries the two emissive assemblies.

The industrial advantages in terms of the realization of the luminescent bulb and the technical improvements are as follows:
- masking of the melted and deformed region of the
welding
- masking of the queusot
- promote better welding of the foot on
the envelope, faster
- to obtain a better sealing of the envelope
in the pellet
- to obtain an envelope in the size of the base,
skirt level
- standardize the tubular appearance of the lamp
- to hide the view of the compulsory welding area
-not absent from dusting
- additional practical aspect
for similar nestable diameters
- direct connection of the bulb, without interme
-diary, by a standardized base, at a voltage
data on the network
- use of standard caps and sockets
- resumption of the diametrical variations of the tubes by
the cone EE-AA 'cone of the neck which can be
more or less tucked into the skirt and adjusted in
ensuring the adaptation of the tubular casing
in the pellet
- eliminates the disadvantages of the prior art
and solves the problems mentioned before.

As regards the economic aspect of the realization, the advantages are
- use of standard and raw glass tubes
stretching
- tube glass is storable
- absence of basin oven with carousel blowers
- reduction in cost price, transfer machines
and alternatives being in number from 100 to 1 compared
pond blowers, and the investment of
reverse order
- lower cost of production, rounded shapes
traditional fluorescent bulbs being elected
- mined
- space saving, the envelope having the same
diameter than the base
- integration in standardization, said bulb
replacing incandescent bulbs, by its
method of attachment and its means: s
- use of standard components and materials or
present in the market
- purchase price of these components very low because
manufactured in large quantities in all countries in
standarts that have become global standards.

 the tubular casing is therefore prepared from cylindrical rods whose outside diameter is close to or corresponds to the inside diameter of the base, (fig. 1), at the skirt level (9).

 This being the straight cylindrical part between the last upper thread dW base, and the end thereof leading to the glassware, in the case of screw base.

 According to the invention, for a tubular bulb mounted on an xdison base, the glass rods are sorted from the outset and have a diameter of 24.5 to 25 millimeters and slightly more, and are cut into sections of 380 millimeters.

 Then these sections are melted in their middle and transformed into a test tube (16) by separation and blowing.

 These tubes are none other than the envelopes (1) (fig. 2) forming the enclosure of the tubular discharge bulb.

 the round bottom (3) delimits the second end of the tubular bulb and the length of the envelope is only a function of the power of the bulb to be produced, also a function of the inter-filament distance (13,15 ) of a foot with two stages of electrodes, low (12) and high (14).

Then, the open walls of the envelopes undergo a reduction operation in diameter AA ′, therefore opposite the round bottom. It is an operation of narrowing the diameter of the tube, or constriction (fig. 1,2) called constriction (4) and which at the level of the shaped length li'k'- C 'can extend by 1 at 50 millimeters, and according to the invention, pl particularly for entering a
E 27 and have a sufficient bearing surface for the realization of the cementing and the welding of the base, with a length of approximately 5 millimeters.

This operation, therefore called "shrinking", spe-cialerent the diameter from 0.1 to 60 millimeters, according to the invention, the diameter of the tube goes from 25 to 21 milli others, a reduction of 4 millimeters
The shrinking is carried out by hot torch (21) on the open end of the tube, by one or more form wheels (20), Figure 1, rotating, with or without pliers, which allows to reduce the diameter to ribs fixed as listed above, and weld the foot.

 I dusting operation ending in BB ', the welding of the foot on the shrinking of the envelope will take place in CC' (fig.3).

making the neck is therefore essential
- to weld the foot - without melting or damaging the envelope
powdered
- to easily carry out foot-shell welding
- to reinforce the weld, this being more resistant
-Aunt with smaller diameter
- to be able to place this weld in the base
- offer a setting area for grouting cement
- to be able to maintain durably and securely
the envelope and the base
- dissipate the weld tensions in the part
shaped from the constriction and not from the envelope, this
being less resistant
shrinking is therefore fundamental for the production of tubular fluorescent bulbs, with tubular base, mounted with Goliath, tison, b 22 or m 14 caps.

 In the latter case, it is possible not to make the constriction according to the manufacturing contingencies, because of the size which is not proportionally reducible of the foot and of the envelope.

 The welding of the foot to the re tubular casing is made directly on it, and from the start of the solidification of the welding glass, shortly after this, the foot is slightly pulled from 1 to 2 millimeters by 5 'In-intermediate of the axial socket (17), so as to obtain an elongated weld and that at no time an excess thickness comes to form and prevent ia as a result the descent of said weld and the tube in the base.

 This weld must be masked by the skirt of said normalized base and glued into its skirt.

 We can consider that the fact of drawing the weld is a slight constriction.

 the tail is sealed after pumping just at the weld on the neck (5).

 A rod can be located on the rod connecting the first to the second stage of electrodes of a foot.

 Once the envelopes have undergone the shrinking already described, they are cleaned and internally lined with a film of fluorescent paste, which after reduction and annealing of the envelope in the oven, becomes the powder (11) tanning the tube. This is then routed to the envelope mounting machines on the stand.

 foot-constricted welding is conventional, and it is carried out in small flame-type rake treks and in one go, for economy, and so as not to heat the very thin glass unnecessarily, in addition to the nuisances already mentioned.

 Welding is carried out on towers or tower carousels.

 the standard production of the tubes and the multiple adjustment factors, not always controllable, of the components of the melting furnace and the feeder mean that the diameter of these tubes can vary by a few tenths of a millimeter.

 They are then all recalibrated to be the same diameter as the caps.

According to the invention, corresponding to the internal diameter of the caps to be fitted or equivalent
In addition, if a slight clearance occurs between the skirt and the tube, the latter is compensated by a slight increase in material - sealing material (10) in no way modifying the character of the invention which always remains, the welding of 'A tubular foot constricted by a tubular casing of the same diameter as the interior of a standardized base, said weld being lowered, masked, and whose retention by Ü cement ars the base ensures that of the envelope.

known fastening methods are
- the litarge
- hot-melt adhesive
- crimping or combinations of these processes.

 In the case of the Goliath bases, B 27 and E 14, one of the two poles of current supply is passed between the junction of the envelope and the base, and welded to the latter at the level of the glassware.

 The rectilinear continuity between the skirt and the wall of the casing is ensured by the choice of tube diameters, so that there is no linear rupture between the wall and the base, this conferring a monolithic appearance on the tubular lamp.

 the application of this assembly comprising a base with two stages of electrodes is valid for all other types of discharge vessel, for other purposes than that of lighting, with or without standardized base, according to the summary state of the various bases in use, namely, the families of E 15, E 22 (fig. 5), BY 22, E 5, E 10, E 14 (fig. 7-10), E 27 (fig. 6), S 39 (fig. 4), z 40, E 41 and G, this, without limitation.

According to a variant specific to the invention, it is pos -sible to use for mounting a fluorescent bulb
- non-tubular feet
- non-cylindrical envelopes.

 Indeed, the French patent N 2,575,600 and the French patent application w 86-16455 define bell pies with four pinched passages, or with two welded passages.

 There are other forms of foot, with concentric passages, blown foot, pinched tubular foot, pressed foot.

 In the same way, it is possible to weld envelopes of different shape, for example spherical, ovoid, cubic and others (fig. 8-9-10), the wall of the hen year being covered with powder until shrinking, which can also be covered with a reflective deposit (18), but in all cases, the welding of the foot on the shrinking envelope is lowered, masked and maintained in a standardized base.

 All the caps mentioned above contain both the ballast and the ignition device allowing them to be connected to the mains from 100 to 250 volts, or other industrial voltages.

In the case where this weld is not hidden in a standardized base, it can be in another, or it is other types of base (fig.11) which may include the electrical elements designated above , or only one of the two, and coming to fit into another socket fixing system, this can then be a standard Edison modified base (fig. 12)
Indeed in a later embodiment, (fig.12), (scale 2), view taking into account the life of the filaments of the tube between 5 and 1w 000 hours, the igniter and that of the ballast greater than 100 00 hours, it becomes possible to dissociate the elements that form the tube and the ballast, for rationalist and eco-nomic concerns.

 The top of the base then carries an insulating part for its seizure.

We can therefore use a special base with 2 or 4 contacts, of various shapes, (fig.11), and with various fixing methods; screw, bayonet, screwing or even of the FRAL type as defined in the patent application
French L0 86-1 6455.

 In all cases, the tubular or ovoid envelope with a constricted weld and containing a foot welded with two stages of electrodes, is lowered, glued by a cement or the like and the weld is masked in the base, the powdered part starting immediately. bora a bora with the top of the base.

 Finally, according to an improvement and variant of the invention, the plane level separating the filament from the bottom of the foot to the top of the skirt of the base can be reduced (fig. 13, scale 2).

 This is either by making an ultra-short foot (19), delicate to produce, or by lengthening the skirt of the base or by the combination of the two sets.

 Indeed each emissive zone of a filament has a certain number of nuisances, it is a zone of degassing, of flickering, reddening for the badly adjusted tubes, the Faraday zone, sky blue color, trembling of the filament. under the electronic shock, and luminescent decay zone beyond the inter-electrode plasma.

 He. it is therefore possible to use a base, the envelope part of the tube can extend up to three centimeters from the welding of the envelope on the base, which welding is always concealed in the base, as defined above.

- Figure 4 shows according to the invention, a cylindrical tubular bulb, with tubular base, as mentioned above, with a wall completely covered with luminescent powder, and in the extension of the base, said bulb being equipped with a Goliath base , - Figure 5 represents the same bulb but with a B 22 base - Figure 6 represents a cylindrical tubular casing according to the invention, fully assembled and equipped with an Edison base - Figure 7 represents the same cylindrical tubular bulb, but equipped of a miniature base, the X 14 - Figures 8,9,10, represent embodiments of feet welded to constriction to non-cylindrical envelopes - Figures 11 represent different methods of attachment capable of equipping said bulbs - Figures 12 and 13 to scale 2 represent for the first a tubular bulb- coming to fit and making contact in a base containing the entire operating system for the second, a base with a particular skirt long masking - the emissive set of bottom of foot

Claims (3)

S X V X i; DICATIONS 10) Bulb according to claims 1 to 7, characterized in that the concealed weld is concealable in other types of base (fig. 11), which then come to fit and be connected in a standardized base acting as receiving socket in its upper part (fig. 12) and comprising the ballast, an igniter and an insulating part for gripping it CLAIMS 1) Low pressure fluorescent light bulb, mercury vapor discharge and luminescent solid with a single base and intended to be connected to the AC sector, characterized in that the solder (5) of a two-stage foot of electrodes on an envelope forming the discharge vessel is produced thereon by a masked neck (4.5) and sealed in a standardized base (7) 2) Bulb according to claim 1, characterized in that the foot is a tubular foot (6) 3) ampoule according to claim 1, characterized in that the envelope is tubular and cylindrical (1) 4j hen according to claim 1, characterized in that the envelopes are test tubes (16) of which each blowing of a round bottom (3) delimits the second end of the envelope 5) Bulb according to claim 1, characterized in that the length of the envelope housing the emissive assemblies is a function of the power of the bulb to be produced by the inter-filament distance (13,15 ) of a foot with two stages of electrodes (12,14) ') Bulb according to claim 1, characterized in that the shrinking operation is carried out hot by torch and knobs (21,20) on the open end of the envelope 7) Bulb according to claim 1, characterized in that the envelopes forming the discharge vessel covered with a reflective offset (18) are of spherical or ovoid shape 8) Bulb according to claim 1, characterized in that the standardized base intended to connect the bulb s ur the sector is suitable for both the ballast and the bulb ignition device 9) bulb according to claim 1, characterized in that an extension skirt @ ed (5) of several cantimeters conceals the filament (13) and the bottom of the foot electrodes (19)