AU2005228934A1

AU2005228934A1 - Portable lamp

Info

Publication number: AU2005228934A1
Application number: AU2005228934A
Authority: AU
Inventors: Jurgen Nolle
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-03-26
Filing date: 2005-03-15
Publication date: 2005-10-13
Anticipated expiration: 2025-03-15
Also published as: JP2007522614A; JP4451883B2; JP4644297B2; DE112005001288A5; CN1938543A; DE202004004984U1; AU2005228934B2; NZ549919A; WO2005095845A2; PL1728023T3; DE502005007319D1; CN1938543B; WO2005095845A3; EP1728023B1; EP1728023A2; JP2010015999A; ATE431920T1

Abstract

The invention relates to a lamp comprising a folding screen which is at least partially provided with a reflective layer and has at least one mobile tensioning means for stretching the folding screen, said folding screen surrounding a luminant in the taut state and in the relaxed state. The inventive lamp comprises blocking means for preventing the screen from folding up when the luminant is hot. Furthermore, an optional tensioning aid and a blocking device can be provided in order to prevent against premature folding of the screen.

Description

WO 2005/095845 1 PCT/DE2005/000469 Portable Lamp The invention relates to a lamp comprising a folding shade which is at least partially provided with a reflective layer and has at least one mobile tensioning means for folding up the folding shade, said folding shade surrounding a lamp in the taut state and in the slack state. Portable lamps with a folding shade are known as hand or standard lamps and are preferably employed for the temporary illumination of rooms or exposed areas. Corresponding to the intended application, the lamps can be lamps of low wattage, or else lamps of up to 1,000 Watt and more. The latter are preferably employed in the open air for the illumination of, for example, a building site, accidents, disaster scenes or sport events. From the European patent application EP 1 059 483, for example, a portable lamp is known, in which a lamp shade is tensioned by a tensioning system. As particular characteristic of this design one can point out that the lamp shade almost completely surrounds the lamp. When using these portable lights, especially if high-power lamps are employed, it showed that these are activated occasionally and unintentionally in a folded state when they are connected to the electrical energy supply. The extreme heat development, that high-power lamps generate, can damage the lamp shade in the process. The object underlying the invention is to provide a portable lamp comprising the advantages according to the European patent application 1 059 483, in which however a means is to be present, that prevents simultaneous tension release of the tensioning system and warm phase of the lamp, and that provides the possibility of facilitated folding up. The object according to the invention is achieved by at least one means being provided that monitors the taut state of the folding shade and/or the temperature of the lamp and by a tensioning aid being provided changing the expenditure of force for folding up the tensioning device, the tensioning means comprising a pulley block, a deflected rope or a transmission. Further advantageous embodiments result from the subclaims. A safety device, which prevents simultaneous tension release of the tensioning system and warm phase of the lamp, ensures that the portable lamp can not be damaged by heat, so that the lamp cannot be activated in the slack state of the folding shade or that no tension release of the folding shade can occur after heating. This results in the advantage that an inadvertently current-bearing lamp does not destroy the folding shade due to heat development. In an advantageous manner, a tensioning aid is provided especially for larger lamp shades, in which the expenditure of force for tensioning the shade is reduced, wherein the tensioning means can be a pulley block, a deflected rope or a transmission. By means of ithe tensioning aid, a larger shade can also be folded up with relatively little expenditure of force, the manual tensioning path of course being lengthened by the tensioning aid. A tensioning aid can be a pulley block where the mechanical folding WO 2005/095845 2 PCT/DE2005/000469 up of the tensioning means is effected by means of deflected ropes. It is however also possible, that the tensioning aid is a transmission driving a coiling roll, that is itself connected to a first end of the tensioning means and winds up a pull rope or a cable, which is connected to a second end of the tensioning means. If the transmission drives this coiling roll, the path between both tension means is reduced by the traction of the coiling roll and the tension means are thus tensioned. In the process, the transmission facilitates the rotation of the coiling roll by reducing the torque for rotating the coiling roll by a corresponding transmission ratio. It is however also possible to employ a rack and pinion gear to tension the tensioning means. In an advantageous manner, the tensioning aid and the locking device are provided in one unit. It is possible to provide the tensioning aid as well as the locking device as individual or different aggregates independent of each other inside the lamp. In an advantageous manner however, the tensioning aid and the locking device are combined in one unit. This has the advantage that the locking device can directly stop the tensioning aid and locking is not effected by different manners inside the lamp. A preferred embodiment of a lamp with a tensioning aid and a locking device is a lamp that winds up a pull band or a cable, the coiling roll being connected to a first end of the tensioning means and the pull band or cable being connected to a second end of the tensioning means and the roll being tensioned by a torsion spring winding up the pull band or the cable when the tensioning means is tensioned, thus preventing the pull band or the cable from winding off by means of the locking device and permitting the tension release of the folding shade only by the release of the locking device. According to the invention, one of the elements of the tensioning means can trigger a circuit breaker in the slack state of the folding shade. In a further advantageous embodiment of the invention, the tensioning means is designed such that the relationship of the tensioning path and the manual triggering path is reversed with respect to the above mentioned embodiment. Thereby, the torque required for tensioning the tensioning means or the force required for the tensioning are increased. At the same time, the triggering path is shortened. This embodiment is especially practical for lamps, whose tensioning shade can be tensioned already with little expenditure of force. An advantage is that a manual pull rope only has to be pulled a short way. As a result, the pull rope does not dangle. A long, dangling pull rope could flap around in wind, it could get tangled with cables or otherwise detrimentally and uncontrollably dangle, which is conceived as very unfavourable for lamps in practical use, especially for emergency uses. The safety device according to the invention can be a circuit breaker, which is arranged in the portable lamp such that the same is triggered by a mobile element of the tensioning means in the slack state. Thus the power supply of the lamp is interrupted in this case. Preferably, the breaker is designed such that the same closes the electric circuit only when the folding shade is completely tensioned. This prevents the lamp from destroying a not completely tensioned shade if the same is prematurely switched on.

WO 2005/095845 3 PCT/DE2005/000469 The device according to the invention is, however, not restricted to a breaking-off of circuit preventing the lamp from being switched on in the slack state of the folding shade, but it can also be a device, that prevents by the lamp itself, for example by heating of the lamp, that the tensioning means can be slackened. It also showed to be advantageous to use an element for locking the folding shade, which element locks the tensioning means of the folding shade in a heated state by thermal expansion only. It would also be possible, for example with an electro magnet, to lock the folding shade in the taut state, the electro-magnet locking the folding shade during the switch-on phase of the lamp by a latch mechanism. An element which, however, is locked only by thermal expansion has the advantage that the same only releases the locking when the lamp of the folding shade has cooled down. The cooling phase can last a few minutes and longer, optionally even 15 minutes and longer, in this cooling phase no power which could supply an electric interlocking mechanism being provided any longer. An element, which locks the tensioning means of the folding shade due to the thermal expansion thus shows an advantage in that it is independent from a power supply, for example after the lamp has been switched off. The locking device is advantageously composed of two elements encompassing each other and being made from different materials, the material of the first element having a thermal expansion coefficient different from that of the material of the second element. It is thus achieved that in the device two elements can slip past each other at ambient temperature, for example outside temperature, but lock one another in the heated state due to the different thermal expansion coefficients. In this locked state, the two elements get stuck and loosen only after cooling. In a first example of an embodiment of the invention, the device is composed of a piston sliding in a hollow cylinder, the material of the piston having a higher thermal expansion coefficient than the material of the hollow cylinder. In this embodiment of the invention, the piston slides along inside the hollow cylinder when the folding shade is tensioned. If the piston is, for example, made from brass, which has a higher expansion coefficient than stainless steel, and if the hollow cylinder is made from stainless steel, the brass piston which also slides along in the stainless steel hollow cylinder, is no longer able to move therein after heating, as the expanded brass piston gets stuck in the stainless steel hollow cylinder which does not expand as much. The device according to the invention, however, is not restricted to a piston sliding in a hollow cylinder. It is also possible, that the heat activated locking device is a ring sliding on a rod. Here it has proved an advantage, if the material of the ring has a lower thermal expansion coefficient than the material of the rod, the rod locking the sliding ring by heating. Instead of a device sliding along or into one another, a latching device can also be used, that, for example, simultaneously locks the shade in the taut state as a normal latching element, this latching device itself preventing a manual unlatching by a latching element. It is, for example, possible, that a bimetal, which is arranged in the cold state, such that the same does not project into the tensioning path of a tensioning means, projects into the tensioning path of a latching element after the expansion or the deformation by heat. By way of example, a latching mechanism as can be found in WO 2005/095845 4 PCT/DE2005/000469 umbrellas is mentioned, wherein a bimetal is arranged inside a rod in the tensioning system that engages with a latch catch in the form of a recess of the central tensioning element of the tensioning system when it is heated. Only after the bimetal has cooled down again and thus indicates the cooling of the whole arrangement, is it possible to unlatch and slacken the folding shade of the lamp according to the invention. According to the invention, the latching element can be held fixed, the latching element blocking another manual latching element, so that the actual latching element can no longer be manually released. It is however also possible that the latching element according to the invention itself blocks or bolts the movement of the tensioning means. According to the invention, however, the latching element can be also arranged on a mobile tensioning element, the latching element projecting into a corresponding latch catch in the heated state. A latch catch can be here a recess in an element of the tensioning device, the latch catch being arranged such that, if the latching element projects into the latch catch, the tensioning device can no longer be released, because the latching clement prevents the lateral movement of two elements in the tensioning device. In an advantageous manner, the lamp according to the invention comprises at least one locking device, which locks the shade in the partially taut state with respect to tension release, however opens the shade with respect to further tension of the tensioning system. Thus it is achieved that with manual tensioning of the shade, which possibly requires a high expenditure of force, one can temporarily release the tension in order to rest, the shade not flying back again due to its own tension force. According to the invention, it is further provided that the device monitoring the taut state of the folding shade and/or the temperature of the lamp is to be considered independently of the tensioning aid which changes the expenditure of force for tensioning the tensioning device, the tensioning means comprising a pulley block, a deflected rope or a transmission. The invention is illustrated below by means of the following figures, wherein Fig. 1 shows a portable lamp with a tensioning means according to the invention, Fig. 2 shows a tensioning aid for the lamp according to the invention, Fig. 3 shows an extended tensioning aid for the lamp according to the invention, Fig. 4 shows the extended tensioning aid from Figure 3 in disassembled form, Fig. 5 shows a bimetal latching device according to the invention in a heated and cooled state, Fig. 6 shows a further heat latching device, and Fig. 7 shows a breaker point according to the invention.

WO 2005/095845 5 PCT/DE2005/000469 Figure 1 shows a tensioning device 1 for a portable lamp 500 according to the invention that tensions the folding shade 300. The tensioning device 1 consists of a telescopic rod assembly 2 with inner telescopic rods 3, 3' and outer telescopic sleeves 4, 4', drawn to be transparent in Figure 1, which are arranged one into the other. At a first end of the telescopic rods 3, 3', which are located inside the telescopic sleeves 4, 4', there are pistons 5, 5' each, which in this example are formed of brass. The telescopic sleeves 4, 4', however, consist of stainless steel. The telescopic rod assembly 2 ends at each of its outer ends in a tensioning gear 6, 6' to which tensioning means 9, 9' are attached and folded up by the tension ring 6, 6'. At the telescopic sleeves 4, 4', a lamp socket 7 is arranged, which receives the lamp 8 that is provided with electrical current by a supply cable 10. In Figure 1, the tensioning device 1 for the portable lamp according to the invention is represented in the taut state, the telescopic rod assembly 2 and the pistons 5, 5' located therein being heated by the lamp 8. Due to a higher expansion coefficient of the pistons 5, 5', these expand more than the inner diameter of the telescopic sleeves 4, 4'. Since the pistons 5, 5' expand more, they get stuck in the telescopic sleeves 4, 4'. In the cooled state the pistons 5, 5' contract again and thus release the stuck state between the telescopic sleeves 4, 4' and the pistons 5, 5', with the result that the telescopic rods 3, 3' can slide out of the telescopic sleeves 4, 4' again without resistance and thus the tensioning means 9, 9' can be slackened. With the slackening of the tensioning device 1, the distance between the tensioning means ring 6, 6' is increased and consequently the tensioning means 9, 9' equatorially move towards the lamp 8, thereby forming a cylinder arrangement of the tensioning means 9, so that the portable lamp can be transported saving space. The lamp socket 7 is attached to a support rod 140 of a support 141. A pair of pull ropes 150, 151' is attached to the pistons 5, 5' and guided through the telescopic sleeves 4, 4'. A grip 150 joins the two pull ropes 151, 151'. If the lamp on the support 141 is possibly erected a few meters high, a manual pull on the pull grip 150 permits the tensioning of the tensioning device I by pulling the telescopic rod 3, 3' into the telescopic sleeves 4, 4' and pulling downwards the upper tensioning ring 6 into the direction of the arrow. Thereby, the upper tensioning ring 6 approaches the lower tensioning ring 6' mounted to the lamp socket and thereby the tensioning means 9, 9' move outwardly, as is indicated by the arrows, resulting in a lamp shade put over the tensioning means 9, 9' being folded up. In Figure 2, a tensioning aid 100 is shown, which also serves as a locking means to lock the tensioning device 1. In this concrete embodiment of the tensioning aid 100, the tensioning aid 100 consists of a coiling roll 101, around which the pull rope 151' in Figure 1 is wound and leaves the same as pull rope 105 above the coiling roll 100. The pull rope 105 is connected with the piston 5' in Figure 1. The coiling roll 101 comprises a brake drum 103. In the brake drum 103, a break-in brake 102 is located, which prevents uncoiling of the pull band or cable 105. If the tensioning means 100 in Figure 2 rotates anti-clockwise, the break-in brake 102 prevents a clockwise uncoiling, because the break-in brake 102 locks inside the brake drum 103. An anti clockwise coiling on the other hand is permitted by the break-in brake 102, so that the tensioning aid 100 can coil the band or cable 105 without resistance. An optional torsion spring 104 serves for a reliable coiling of the band or cable 105, the torsion spring 104 imparting as much torque to the tensioning aid 100 that the same coils the pull band or the cable 105 despite its own rigidity. The torsion spring 104 is primarily WO 2005/095845 6 PCT/DE2005/000469 not intended for serving as a facilitation of tension force, but it is possible to incorporate such a strong torsion spring 104, that it facilitates the tensioning of the tensioning device I in Figure 1. For releasing the tensioning aid 100, the break-in brake 102 is lifted from the brake drum 103 by means of the tripping device 160, with the result that the tensioning aid 100 permits the slackening of the tensioning device 1 in Figure 1 by the uncoiling of the coiling roll 101. For better accessibility, a non depicted thread can be attached to the tripping device 160. In an alternative embodiment of the break-in brake 102, the same is constructed like a roller blind catch, so that the break-in brake 102 releases its locking by momentarily activating the coiling roll 100 and thus permits the slackening of the tensioning means 9, 9' in Figure 1. In a particular embodiment of the break-in brake 102, the same is not completely released, but brakes a movement of the coiling roll 100, so that a slackening of the tensioning means 9, 9' does not occur suddenly, but slowly. This helps to avoid accidents. In Figure 3 an extended tensioning means 200 is shown, which, in addition to the already described tensioning aid 100, comprises a further coiling roll 110 on a common axle 90, the coiling roll 110 comprising a direction of winding reversed or equal to the tensioning aid 100. This additional roll 110 with reversed or equal direction of winding serves the admission of a pull rope 111, which can be operated by a grip 112. If one pulls the pull rope 111 by means of the handgrip 112, the coiling roll 110 uncoils and simultaneously the tensioning aid 100 coils and thus shortens the path of the pull band or the cable 105 inside of the tensioning device 1 in Figure 1. Thereby, the tensioning device 1 in Figure 1 is tensioned, because the path between the tension rings 6, 6' is shortened. In a particular embodiment of the invention it can be provided that the roll 110 and the tensioning aid 100 are interconnected in the extended tensioning aid 200 via an epicyclical gear 109, so that the roll 110 rotates faster when uncoiling than the tensioning aid during tensioning. Thereby, a torque increase during the transmission from the pull band 111 to the pull band or cable 105 is achieved, which means assistance, particularly for large lamps with correspondingly larger tensioning devices 1. Alternatively or in combination with this, the coiling roll 110 can also comprise a square in its axle centre, into which a crank 113 can be inserted for manually operating the crank. Like when pulling the pull band 111 by the handgrip 112, by rotating the crank 113 it can be achieved that the tensioning aid 100 coils the pull band or the cable 105 and thus tensions the tensioning device I in Figure 1. In an exactly contrary manner, the epicyclical gear 109 can also link the tensioning aid 100 and the coiling roll 110, such that the pulling path of the pull band 111 with respect to the pulling path of the pull band or cable 105 is shortened. This way of linking is suited for lamps, whose tensioning device I can be tensioned with little force. By the shortening of the pulling path, it is achieved that the pull band 11 does not project so far from the tensioning aid 200 after tensioning and thus does not unfavourably dangle from the lamp. In Figure 4, the tensioning aid 200 from Figure 3 is represented in a disassembled form, where a view on the tensioning aid 100, on the exposed epicyclical gear 109 and on the coiling roll 110 is provided. The tensioning aid 100 is identical to the tensioning aid from figure 2, except for its seat on the common axle with the WO 2005/095845 7 PCT/DE2005S/000469 epicyclical gear 109. Depending on the desired gear reduction or ratio, the tensioning aid 100 is coupled with the sun wheel 106 of the epicyclical gear 109 or meshes with an internal toothing (not shown here) on the back side of the tensioning aid 100 with the three planetary gears 107, 107', 107" of the epicyclical gear 109. Correspondingly, the coiling roll 110 acts on the sun wheel 106 or on the three planetary gears 107, 107', 107". If one pulls the pull band 1 l by the grip 112, the coiling wheel 110 moves anticlockwise. If the coiling roll is connected to the sun wheel 106 of the epicyclical gear 109, the central sun wheel 106 of the epicyclical gear 109 meshes with the three planetary gears 107, 107', 107". The planetary gears 107, 107', 107" have a stationary axle on the casing of the epicyclical gear 109. Thereby, the three planetary gears 107, 107', 107" mesh clockwise against the sun wheel 106, and the three planetary gears 107, 107', 107" mesh against an internal toothing (not shown here), which is arranged on the backside of the tensioning aid 100 (not shown here). Thereby, the tensioning aid 100 also rotates clockwise, so that the pull band or cable 105 is coiled. Since the sun wheel 106, which is connected with the coiling roll 110 on the axle, has to be rotated several times, so that the tension roller 100 performs a rotation, the torque which is required for tensioning the tensioning device I in Figure 1 at the tensioning aid 100 is reduced during the transmission to the coiling roll 110. If the coiling roll 110 is not connected on the axle of the sun wheel 106 but meshes with an internal toothing (not shown here) on the backside of the coiling roll 110 at the three planetary gears 107, 107', 107", and if the tensioning device 100 is connected on the axle of the sun wheel 106 of the epicyclical gear 109, the torque ratio thus is reversed, leading to the above illustrated benefits. In Figure 5, a latching arrangement 11 according to the invention for the telescopic rod assembly 2 of a portable lamp from Figure 1 is represented. The latching arrangement 11 is arranged inside a telescopic rod assembly 2, which here consists of a telescopic rod 12 and a telescopic sleeve 13. At a bolt axle 14, which is arranged inside the telescopic rod 12, a bolt 15 is located, which is pulled by a bolt spring 16 into the inside of the telescopic rod 12. A bimetal 18 is arranged at a bimetal bearing 17, which bends in a heated state and thus pushes the bolt 15 outside against the pulling of the bolt spring 16. In the taut position of the telescopic rod assembly 2, the bolt 15 can project from a recess 19 in the telescopic sleeve 13 and thus prevent the expansion of the telescopic rod assembly 2. In the right image of Figure 2, the same latching arrangement is represented, where, however, the bimetal 18 in the cooled state has a different shape, and thus the bolt spring 16 pulls the bolt 15 into the inside of the telescopic rod 12. The bolt 15 thus opens the way for the expansion of the telescopic rod assembly 2, so that the inner telescopic rod 12 can slide inside the telescopic sleeve 13. In Figure 6, a further embodiment of the latching arrangement 11 for the telescopic rod assembly 2 of a portable lamp from Figure 1 is represented. Instead of a bimetal, which slides into a latch catch, it is also possible to design the latching arrangement by a brass cylinder 170, which is put over an inner telescopic rod 12 and slides in the telescopic sleeve 13. The brass cylinder 170 expands inside of the telescopic sleeve 13 when it is heated and thus gets stuck, whereby the telescopic rod 12 can no longer slide inside the telescopic sleeve 13. If it cools down, the brass cylinder 170 contracts again within the telescopic sleeve 13 and allows the sliding of the telescopic sleeve 12 inside of the telescopic sleeve 13.

WO 2005/095845 PCT/DE2005/000469 In Figure 7, a breaker arrangement 20 according to the invention for a telescopic rod assembly 2 of a portable lamp is represented. In the taut state, a recess 21 is arranged under a breaker point 22, such that a sliding block 23 can connect a supply line 24, thus forming an electrical contact between contacts 25 and contact rod 26. The sliding block 23 is arranged at a contact rod 26 and rotates about an axle 27, which is arranged in the breaker case 28. A sliding block spring 29 pushes the sliding block 23 towards the recess 21 of the telescopic rod 12. If the telescopic rod assembly 2 is retracted or extended, the sliding block 23 is retracted due to the shifted recess 21 into the inside of the breaker case 28, thereby opening the contact between the contact rod 26 and the contact 25, so that the supply line 25 is electrically broken. List of reference numerals: 1 Tensioning device 2 Telescopic rod assembly 3 Telescopic rod 4 Telescopic sleeve/ hollow cylinder 5 Piston 6 Tension ring 7 Lamp socket 8 Lamp 9 Tensioning means 10 Supply cable S11 Latching arrangement 12 Telescopic rod 13 Telescopic sleeve 14 Bolt axle 15 Bolt 16 Bolt spring 17 Bimetal bearing 18 Bimetal 19 Recess 20 Breaker arrangement 21 Recess 22 Breaker point 23 Sliding block 24 Supply line 25 Contact 26 Contact rod 27 Axle 28 Breaker case 29 Sliding block spring 90 Axle 100 Tensioning aid 101 Coiling roll 102 Break-in brake 103 Brake drum 104 Torsion spring 105 Pull band/Cable 106 Sun wheel WO 2005/095845 9 PCT/DE2005/000469 107 Planetary gear 107' Planetary gear 107" Planetary gear 108 Attachment arrangement 109 Epicyclical gear 110 Coiling roll 111 Pull rope 112 Grip 113 Crank 140 Support 141 Support rod 150 Pull grip 151 Pull rope 151' Pull rope 160 Tripping device 161 Brake shoe pin bushing 170 Brass cylinder 200 Tensioning aid 300 Folding shade 500 Lamp

Claims

1. Lamp (500) comprising a folding shade (300) at least partially provided with a reflective layer, at least one mobile tensioning means (2, 9) for folding up the folding shade (300) being provided, said folding shade (300) surrounding a lamp (8) in the taut state and in the slack state, characterised in that at least one device (11, 20) is provided, which monitors the taut state of the folding shade and/or the temperature of the lamp (8), and in that a tensioning aid (100, 200) is provided, which changes the expenditure of force for tensioning the tensioning device (I), the tensioning means (100, 200) comprising a pulley block (100), a deflected rope (105) or a transmission (109).

2. Lamp (500) comprising a folding shade (300) at least partially provided with a reflective layer, at least one mobile tensioning means (2, 9) for folding up the folding shade (300) being provided, said folding shade (300) surrounding a lamp (8) in the taut state and in the slack state, characterised in that a tensioning aid (100, 200) is provided, which changes the expenditure of force for tensioning the tensioning device (1), the tensioning means (100, 200) comprising a pulley block (100), a deflected rope (105) or a transmission (109).

3. Lamp (500) comprising a folding shade (300) at least partially provided with a reflective layer, at least one mobile tensioning means (2, 9) for folding up the folding shade (300) being provided, said folding shade (300) surrounding a lamp (8) in the taut state and in the slack state, characterised in that at least one device (11, 20) is provided, which monitors the taut state of the folding shade and/or the temperature of the lamp (8).

4. Lamp according to claim I or 3, characterised in that at least one of the devices (11, 20) interrupts an electrical power supply of the lamp (8) in response to the state of tension of the tensioning device (1).

5. Lamp according to claim 1, 3 or 4 characterised in that WO 2005/09584S 11 PCT/DE2005/000469 at least one of the devices (11, 20) locks the tensioning means (2, 9) of the folding shade (300) in response to the temperature of the lamp (8).

6. Lamp according to claim 5, characterised in that the device (11, 20) comprises an element (5, 5'), which locks a tensioning means element (3) of the tensioning means (2, 9) by thermal expansion.

7. Lamp according to claims 1, 3, 5 or 6 characterised in that the device (11, 20) consists of two elements (4, 4',5, 5') encompassing each other and being made from different materials, the material of the first element (4, 4') having a thermal expansion coefficient different from that of the second element (5, 5').

8. Lamp according to claim 7, characterised in that the device (11, 20) is a piston (5, 5') sliding in a hollow cylinder (4, 4'), the material of the piston (5, 5') having a higher thermal expansion coefficient than the material of the hollow cylinder (4, 4').

9. Lamp according to claim 7, characterised in that the device (11, 20) is a ring sliding on a rod (3, 3').

10. Lamp according to claims 1, 3, 5 or 6, characterised in that at least one element (2) of the tensioning means (9) is locked by a latching element (15), the latching element (15) projecting into the otherwise free tension path of the element (2) of the tensioning means (9) due to the thermal expansion.

11. Lamp according to claim 9, characterised in that the latching element (15) is held fixed and blocks or bolts the movement of the tensioning means (2, 9).

12. Lamp according to claim 9, WO 2005!095845 12 PCT/DE2005/000469 characterised in that the latching element (15) is arranged on the tensioning element (2) and projects into a corresponding latch catch (19) in the heated state.

13. Lamp according to claim 4, characterised in that at least one element (21) of the tensioning means (2, 9) activates an electrical breaker (20) in a slack state.

14. Lamp according to one of claims 2 to 11, characterised in that at least one locking means (102) is provided, which locks the tensioning device (1) in a partially taut state.

15. Lamp according to claim 1 or 2, characterised in that the tensioning aid (100, 200) and the locking means (102) being present in a unit. 1J 6. Lamp according to claim 15, characterised in that the tensioning aid (100, 200) comprises a coiling roll (101) that coils a pull band or a cable (105), the coiling roll (101) being connected to a first end (6') of the tensioning means (9, 9') and the pull band or cable (105) being connected to a second end of the tensioning means (6), and the coiling roll (101), tautened by a torsion spring (104), coils the pull band or the cable (105) when the tensioning means (9, 9') are tensioned, thereby preventing an unintentional uncoiling of the pull band or the cable (105) by locking means (102) and permitting the slackening of the tensioning device (1) only by releasing the locking means (102).

17. Lamp according to claims 1, 2, 15 or 16 characterised in that the tensioning aid (200) consists of two coiling rolls (101, 110) arranged on an axle, which are interconnected via an epicyclical gear (109), a first pull band or cable (105) of the first coiling roll (101), which is attached to a first end (6') of the tensioning means (9, 9'), being attached to a second end (6) of the tensioning means (9, 9'), and a second coiling roll (110) WO 2005/095845 13 PCT/DE2005/000469 comprising a pull band (111), that, when it is uncoiled, drives the first coiling roll (101) via the epicyclical gear (109), so that the same is coiled.

18. Lamp according to one of claims 1, 3 or 15 to 17, characterised in that the tensioning aid (200) shortens the manual tensioning path or lengthens the manual tensioning path, thereby decreasing the pull.

19. Lamp according to one of claims 14 to 1 8, characterised in that the locking means (102) permits a continual braking of the slackening of the tensioning device (1).