GB2224344A

GB2224344A - A reflector device for a lamp

Info

Publication number: GB2224344A
Application number: GB8918731A
Authority: GB
Inventors: Walter Haberthur
Original assignee: Bron Elektronik AG
Current assignee: Bron Elektronik AG
Priority date: 1988-08-17
Filing date: 1989-08-16
Publication date: 1990-05-02
Also published as: CH679179A5; DE8810381U1; GB8918731D0

Description

2224344 A Reflector Device for a Lamp The invention relates to a reflector

device for a lamp according to the preamble of claim 1.

From many cases of application,, it is a known practice to arrange the 5. light source of the lamp in the reflector such that it can be displaced in the longitudinal axis in order to achieve a variable lamp angle. With flash guns it is necessary in this case to incorporate a device in the lanp which makes it possible to displace the unit of focusing light and flash tube. This adjustment device has to be paid for by every buyer of 10. this lamp, including cutomers who do not require the adjustment device itself.

The underlying task of the invention is to design the generic reflector device in such a way that the lamp angle can be changed without a costly 15. adjustment device for the light source.

With the generic reflector device, this task is solved according to the invention by the characterising features of claim 1.

20. In the case of the reflector device according to the invention, the adjustable reflector part is provided which is displaced relative to the connection for the lamp. The lamp angle can be very easily changed by adjusting the reflector part. The light source of the lanp itself remains fixed in position, so that a costly adjustment device is not required for it either. The reflector housing is attached to the connection on the lamp, so that the reflector housing and the light source are fixed in position relative to one another. Solely the adjustable reflector part then has to be adjusted to change the lamp angle relative to the connection and thus to the light source. The lamp 30. can be any suitable lamp, such as a flash lamp or a reflector lamp. Since the adjustment device is provided on the reflector, only those persons need buy an adjustable reflector who actually require one. Since the reflector device itself is adjusted, it is possible to fit such a reflector device subsequently on lamps in which a change in the lamp 35. angle would otherwise be impossible.

Further features of the invention are given in the further claims, the description and the drawings.

The invention is explained in greater detail with the aid of an example of embodiment represented in the drawings.

Fig. 1 Fig. 2 10.

shows a rear view of a reflector according to the invention, shows in the upper half an axial cross-section and in the lower half a side view of the reflector according to the invention in accordance with Fig. 1.

The reflector is designed to be adjustable. so that the laffp angle of the reflector can be changed. Preferably,, the reflector is designed so 15. that the lamp angle can be adjusted continuously. It is, however, perfectly possible to provide defined adjustment values on the reflector, by means of which the lamp angle can be adjusted continuously.

20. The reflector has on its rear side a holding device 1 which is preferably bolted onto the rear side of the reflector housing 2. The holding device has a shoulder 3 (Fig. 2) which points radially outwards and by means of which it is attached lying adjacent to a flat rear side 4 of a fixed housing part 5. The shoulder 3 changes over into a 25. cylindrical neck 6 which projects beyond the rear side of the fixed housing part 5. As Fig. 1 shows, cut-outs 7, 7' for lwp back stops (not shown) are provided in neck 6 lying diametrically opposite one another. If the reflector is attached to the lamp, then it is fitted onto the lairp in such a way that the laTrp back stops can be inserted into the 30. cut-outs. Finally,, the reflector only has to be rotated in the known manner so.that the lamp back stops hold the reflector securely. Any other suitable holding device can obviously be used for this reflector.

The fixed housing part 5 has an essentially flat rear side 8 which is 35. provided concentrically with a recess 9, the bottom 4 of which forms the l.' i contact surface for the shoulder 3 of holding device 1. The recess 9 is of a depth such that the shoulder 3 lies completely in the recess 9. The bottom 4 is provided concentric with a circular cut-out 10, the diameter of which corresponds to the internal diameter of the neck 6 of holding 5. device 1.

The rear side 8 of housing part 5 transform via a conical envelope surface 11 into a cylinder envelope 12, which lies concentrically with the cut-out 10 and the holding device 1. Grips 13 are attached. at the 10. transition to the cylinder envelope surface 11, to the cylinder envelope 12 spaced preferably uniformly around its periphery. They each have cap-shaped grip bodies 14,. through the bottom of which a screw 15 passes, by means of which the grip body is attached releasably to the cylinder envelope 12.

15.

On the bottom part 4 facing away from the shoulder 3 there is a reflector part 16 attached to the housing part 5, said reflector part being attached in an adjacent fashion to the bottom 4 by means of a ring-shaped rim 17. Preferably, the shoulder 3 of the holding device 1 20. and the rim 17 of the reflector part 16 are attached to the housing part 5 by means of the same screws. The rim 17 extends up to the edge of the cut-out 10 and then changes over in a curved fashion into a reflector section 18, which lies inside the housing part 5 and projects from it in the axial direction by more than double the axial length. The reflector 25. surface 19 of the reflector section 18 lies on a paraboloid surface which forms the reflector surkace. It can of course lie on any other suitably designed surface.

The overall reflector surface 19. 19' of the reflector is provided on 30. two reflector parts, namely on the fixed reflector part 16 and on an adjustable reflector part 20 which can be adjusted relative to the fixed reflector part 16 in the axial direction. The adjustable reflector part 20 projects in each position axially out the reflector housing 5. The two extreme positions of the adjustable reflector part 20 are indicated 35. in Fig. 2 by unbroken and dot-dashed lines. On its end facing away from 1 the reflector part 16, the reflector part 20 is provided with a cylindrical edge section 21 enlarged in diameter, the free end 22 of which is flanged. In order to guide the reflector part 20, an inner housing part 23 is provided which has a cylinder envelope 24, with which S. it is adjacent to the inside of the cylinder envelope 12 of the outer housing part 5. The end 25 of the cylinder envelope 24 facing the rear side 8 of the outer housing part 5 is bent inwards in bevel fashion so that, when the inner housing part 23 is displaced, there is no risk of it catching on the inside of the cylinder envelope 12.

10..

At the other end the cylinder envelope 24 changes over into a ring-shaped part 26 pointing radially inwards which in turn changes over into an attachment part 27 which lies with its surface adjacent to the reflector part 20. The two parts 26 and 27 of the inner housing part 23 15. can be provided around the whole periphery. In order to save material, however, it is sufficient for these parts 26, 27 to be provided only in the area of the guide elements 28 yet to be described and to be designed, for example, in the form of a bracket. The attachment part 27 is attached, for example, by rivets to reflector part 20. on the 20. intermediate part 26 between the cylinder envelope 24 and the attachment part 27 there is a thread block 28 attached, into which a screw 29 is screwed which passes through the cylinder envelope 12 of the outer housing part 5 and the cylinder envelope 24 of the inner housing part 23. in the area outside the reflector, the screw 29 is enclosed by a 25. grip sleeve 30 which sits on the screw and is held by it. A number of such grip sleeves 30 are provided preferably uniformly spaced around the periphery of the cylinder envelope 12. By means of these, the adjustable reflector part 20 can be adjusted to fix or change the lamp angle relative to the fixed reflector part 16.

30..

In the cyinder envelope 12 of the outer housing part 5, there are guide, slots 31 each running along a spiral, the width of said guide slots preferably corresponding to the diameter of screw 29 in the area where it passes through this guide slot. The cylinder envelope 12 has a number 35. of guide slots 31 corresponding to the number of grip sleeves 30, said 1 g guide slots being arranged preferably uniformly spaced around the periphery of the cylinder envelope. This allows the reflector part 20 to be adjusted uniformly and reliably.

5.

Fig. 2 shows with unbroken lines the reflector part 20 in one of its end positions, the reflector surface 19' of which forms a continuation of the reflector surface 19 of the fixed reflector part 16. Between the two reflector parts 16, 20 there is only a small gap 32 which extends around the periphery of the reflector parts 16, 20. This gap 32 is provided in 10. order that the reflector part 201 when displaced over the fixed reflector part 16, can be displaced into the other end position represented in Fig. 2 by dot-dashed lines. To do this., it is necessary to rotate the reflector part 20 by means of the grip sleeves 30. Since its screws 29 are guided in slots 31 running spirally, the reflector 15. part 20 is not only rotated around its axis, but is also displaced axially according to the gradient of the guide slots. In this way, the reflector part 20 can be adjusted continuously into any desired position between the two end positions shown in Fig. 2. Since the inner housing part 23 is rigidly attached to the reflector part 20. this housing part 20. is also moved with the latter. It ensures, through its cylinder envelope 24 which lies adjacent to the inside of the cylinder envelope 12, a reliable adjustment of the reflector part 20. It is guided by this housing part 23 in a trouble-free manner and is exactly aligned in each position. The gap ensures that during displacement the edge 33 of 25. reflector part 20 facing the reflector part 16 does not catch on the opposite edge 34 of the fixed reflector part 16.

As Fig. 2 clearly showst the conponents 23 and 28 required for the adjustment and guidance of reflector part 20 are concealed in the space 30. between the reflector part 20 and the cylinder envelope 12 of the outer housing part 5. They do not therefore interfere with the beam path inside the reflector.

When reflector 20 is in its drawn-out position, the gap 32 is so small 35. that it does not interfere noticeably when the reflector is in use.

To change the lamp angle.. the light source is not shifted, but remains fixed inside the space enclosed by the reflector parts 16, 20. Thust the lamp onto which the reflector is fitted does not have to have any device for the purpose of shifting, in the case of flash guns for example, the 5. unit of focusing light and flash tube. It is thus possible also to change the lairp angle on 1"s without a displaceable light source merely by fitting the described reflector onto such a lamp. The lamp angle can be adjusted in a very sinple manner by means of grips 30.

10. Instead of the described cylinder envelopes 12,, 24 sliding against one another, the displacement of the reflector part 20 can also be carried out in another way,, for example by guide bolts and suchlike. The crucial factor is that the reflector has a displaceable reflector part which merely has to be displaced in the axial direction to adjust the lamp 15. angle.

1 1 ZS

Claims

Claims

5.

l. A reflector device for a lanp with a reflector housing in which at least one reflector is provided and which has a connection for the lamp, characterised in that the reflector has a least one adjustable reflector part (20) which can be adjusted relative to the connection (1).

2. A device according to claim l# characterised in that the adjustable reflector part (20) is guided in the reflector housing (2).

3. A device according to claim 1 or 2, characterised in that the 10. adjustable reflector part (20) is adjustable relative to a fixed reflector part (16).

4. A device according to claim 3r characterised in that the fixed reflector part (16) is attached to the reflector housing (2).

15.

5. A device according to any one of claims 1 to 4, characterised in that the two reflector parts (16, 20) lie flush with one another in one of the end positions of the adjustable reflector part (20).

20. 6. A device according to any one of claims 1 to 5, characterised in that the adjustable reflector part (20) is provided with at least one guide part (29, 30) by means of which it can be guided along a counterstay (31).

25. 7. 4 device according to claim 6, characterised in that the guide part is formed by a screw (29) attached to the adjustable reflector part (20), said screw preferably carrying a grip part (30), preferably a grip sleeve.

30. 8. A device according to claim 6 or 7. characterised in that the counterstc?y (31) is a slot in the reflector housing (2).

9. A device according to any one of claims 6 to 8, characterised in that the counterstay (31) is a gradient element, preferably running spirally.

35.

10. A device according to any one of claims 1 to 9, characterised in that at least one guide cylinder (23, 24) is attached to the adjustable reflector part (20), said guide cylinder being guided in the inner wall of the reflector housing (2j.

5.

11. A device according to claim 10f characterised in that the guide cylinder (23, 24) carries the guide part (29, 30).

A 12. A device according to any one of claim 1 to 11, characterised in 10. that the adjustable reflector part (20) is adjustable essentially axially.

13. A device according to any one of claims 1 to 12r characterised in that the guide cylinder (23, 24) lies in the area between the wall (12) 15. of the reflector housing (2) and the adjustable reflector part (20).

14. A device according to any one of claims 1 to 13t characterised in that there is a gap (32) between the two reflector parts (16, 20) in one of the end positions.

20.

15. A device substantially as hereinbefore described with reference to and as illustrated in the accaq:)anying drawings.

1 1 Published 1990&tThe Patent Office, State House.68171 High Holborn. LondonWCIR4TP. Further copies maybe obtained from ThsfttentOfflee. Sales Branch, St Mary Cray, Orpington, Kent BR5 3RD. Printed by Multiplex techniques ltd. St Mary Cray, Kent. Con. 1/87