GB2435507A

GB2435507A - Freestanding lamp housing having height and reach controlled by extensible rods

Info

Publication number: GB2435507A
Application number: GB0604028A
Authority: GB
Inventors: John Herbert Brown; Andrew John Elsey
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-02-28
Filing date: 2006-02-28
Publication date: 2007-08-29
Anticipated expiration: 2026-02-28
Also published as: GB0604028D0; GB2435507B

Abstract

A lamp unit 1 is suspended by a flexible connection 3, such as a cable or linkage, from an anchor block 4. The anchor block 4 is rigidly attached to two flexible rods 7, 7a. The flexible rods are held parallel to each other at spaced locations along their length by means of a number of spacer blocks 8. The flexible rods form a natural arc by reason of the weight of the lamp unit 1. The rods are supported by a control box 2 and extend through a rigid tube 9. Each rod has an associated rack and pinion drive 10, 11. When the outermost rod is lengthened and/or the innermost arm is shortened the arc changes shape and causes the lamp unit 1 to lower. Conversely the lamp unit is raised when the outer arm is shortened and/or the innermost arm is lengthened. When both rods are moved synchronously the reach of the lamp increases or decreases.

Description

A LAMP ASSEMBLY

This invention relates to a iamp assembly and more particularly to a free-standing iamp, for example a floor standing or table or desk standing lamp.

An object of this invention is to provide a lamp which may be adjusted relative to a base to illuminate work areas of differing heights and reaches, preferably without the need for a user to contact any of the lamp parts or any suspension parts.

According to this invention there is provided a lamp assembly comprising a lamp housing, a base and two flexible support members connecting the lamp housing with the base. The support members are sufficiently rigid to support the lamp housing but capable of bending under load, such that the support members each form an arc, in use, with one support member radially outwardly of the other. A distal end of one support member is connected to an adjacent distal end of the other support member, and the length of at least one support member between the lamp housing and the base is variable independently of the length of the other support member between the lamp housing and the base to vary the radius of curvature of the arc.

With the construction according to the invention the position of the lamp housing relative to the base can be varied by varying the radius of curvature of the arc simply by varying the effective length of at least one of the support members between the base and the lamp housing. The weight of the lamp housing assists in establishing a curvature of the support members.

In a preferred embodiment, the support members are substantially parallel. However, this is not necessary and an effective lamp assembly may be provided with support members that diverge away from their point of connection. The support members may be maintained in parallel relationship by a plurality of guides located in mutually spaced relationship along the support members.

The support members may contact each other along their lengths between the lamp housing and the base. Preferably, however, the support members are spaced in the radial direction of the arc. In this way, larger differences in the lengths of the support members can be achieved for support members of a given stiffness, because the spacing of the support members provides leverage. A flexible spacer may be located between the support members.

The connection between the support members may be at their ends closest the base.

Preferably, the support members are interconnected at their ends closest to the lamp housing. In this way, any drive or adjustment mechanism for varying the relative lengths of the support members may be located remote from the lamp housing, which may be hot.

Furthermore, in this configuration, the drive or adjustment mechanism will not add to the weight of the lamp housing. The support members need not be connected at their very ends and their may be a section of each support member that extends between their connection point and the lamp housing (or the base, if they are connected at their end closest to the base).

In accordance with the invention, the length of only one of the support members may be variable, with the length of the other support member remaining constant. Preferably, though, the length of each support member between the lamp housing and the base is variable independently of the length of the other support member between the lamp housing and the base. In this way, a greater degree of variability of the position of the lamp housing relative to the base is provided.

Desirably, the lengths of the support members between the lamp housing and the base can be varied synchronously to vary the distance between the lamp housing and the base. In this way, the overall length of the support members can be varied, as well as the radius of curvature of the arc. Thus, the relative displacement of the support members in the longitudinal direction provides a greater or lesser degree of curvature of the support members and the support members may be further arranged so that they may be moved longitudinally and synchronously thus affording a variation in the overall length of the support members.

Conveniently, the lamp housing may be mounted to hang under its own weight, so that it always faces downwardly regardless of the curvature of the arc. For example, the lamp housing may be freely pivoted at the ends of the support members to maintain a freely hanging orientation. The height of the lamp may be controlled by synchronous adjustment of the support members whereas curvature, affecting reach, may be controlled by relative displacement of the support members.

The lamp assembly may comprise a drive mechanism arranged to retract or extend the proximal (unconnected) end of at least one support member into or out of the base or the lamp housing to vary the effective length of the support member. Preferably, the drive mechanism is arranged to retract or extend the proximal end of at least one support member into or out of the base. More preferably, the drive mechanism is arranged to retract or extend the proximal ends of both support members, most preferably independently. A rigid tubular support member may be provided which extends from the bases and houses the lower section of the support members.

The drive mechanism may comprise a pinion cooperating with a toothed rack operatively connected to the support member. Alternatively, the drive mechanism may comprise an axle operatively connected to a coiled portion of the support member. The drive mechanism may be manually operated by the user, for example by turning a knob or handle. Preferably, however, the drive mechanism is powered using a motor drive, which is preferably actuated through remote control means, such as a wireless remote control.

As an alternative to a drive mechanism, the lamp assembly may comprise a heating device to vary the length of at least one support member between the lamp housing and the base by thermal expansion. The heating device may include a power source to generate a heating current in the support member.

The support members may be located within a flexible conduit. Furthermore, a plurality of pairs of support members can be positioned side by side and controlled together. The support members may comprise rods or strips, of spring steel or carbon fibres for example. Other possible configurations include laminated assemblies, multi-strand or fibrous cables either with or without sheathing. For lateral stability, flat strips are preferred.

Particularly in the case of low-voltage lamps the support members may comprise conductors supplying current to the lamps from the base.

Embodiments according to this invention and preferred features are shown and described by way of example only in conjunction with the drawings. In the drawings: Figure 1 shows a complete assembly of one embodiment of a lamp, Figure 2 shows an enlarged view of the lamp unit, Figure 3 shows one embodiment of a control box unit, Figure 4 shows an alternative embodiment of a control box unit, Figure 5 illustrates three different spatial positions for the lamp unit using the control box of Figure 3, and Figure 6 illustrates two different spatial positions for the lamp unit using the control box of Figure 4.

Referring to Figures 1 and 2 of the drawings, a lamp unit I is suspended by a flexible connection 3, such as a cable or linkage, from an anchor block 4. The lamp unit 1 contains multiple light sources 5 which may be filament lamps, light emitting diodes or any other kind of light emitter. At any rotational position of the anchor block 4 the lamp unit rim 6 remains parallel to the ground. The anchor block 4 is rigidly attached to the ends of two flexible arms 7, 7a, in this case in the form of springy rods or flat strips, to ensure that the relative position of the flexible arms at the points of attachment to the block 4 remain constant. More than one pair of flexible arms may be provided positioned, for example, in side by side relationship. The arms may be strips providing lateral stability whilst permitting flexure in a vertical plane.

The flexible arms are held parallel to each other at spaced locations along their length by means of a number of spacer blocks 8 or, alternatively, by a single elongate flexible spacer which may completely enclose or encapsulate the flexible arms 7, 7a. The flexible arms form a natural arc by reason of the weight of the lamp unit 1.

When the outermost arm is lengthened andlor the innermost arm is shortened the arc changes shape and causes the lamp unit I to lower. Conversely the lamp unit is raised when the outer arm is shortened and/or the innermost arm is lengthened.

Fig 5 shows three different positions in the movement of the lamp unit 1 for three differing positions of adjustment of the arms 7, 7a. A change in the length of the outer arm 7 of 10mm gives approximately 3 50mm change of lamp unit height at a span of I.5m. The arm length change is activated from within the control box 2 by means of simple gear drive.

When both arms are lengthened the lamp unit reach increases and, conversely, when both arms are shortened the lamp unit reach decreases. This is illustrated in Fig. 6.

Fig 3 shows in detail a simple sprocket gear 10 driving a linear toothed rack 11 at the end of each of the arms. As an alternative a worm gear or rubber friction drive arrangement may be used to produce the length changes. Thus the arms are capable of adjustment separately or synchronously. Control means may be provided to adjust the drive so that the arms adopt preselected positions using, for example, stepper motors and a control circuit incorporating a programmable memory.

Fig 4 shows in detail an alternative method in which the flexible arms 7, 7a are formed into coils 12 within the control box end. These coils 12 are rotated to wind or unwind the ends of the arms to achieve the maximum lamp unit height change and the maximum lamp reach change as shown in Fig 6.

In an alternative arrangement the outer arm 7 can be length adjusted by application of heat through heating cables attached to the outer arm or by an electric current passed through the arm.

The control box may include a rigid guide bar or tube 9 which may be straight or curved.

This bar or tube 9 will be rigidly attached to the control box and allows passage of the flexible arms.

The gear or coil activation can be manually actuated or motorized and activated by switches in the control box or remotely using wireless means such as by radio control or infra-red.

The lamp unit may contain multi-coloured light emitting diodes to enable the lamp box to emit light of various colour temperatures or colours as well as differing intensities by way of manual or remotely controlled switching.

A low voltage version may contain light emitting diodes of three or four different colours; red, green, blue and white. A multiple of up to five flexible arms provide the power supply to each colour group of light emitting diodes and the common or return path for the current.

The control box may contain a required number of rechargeable cells and an input plug to enable the whole assembly to be free of loose supply cables except when charging the cells. The control box may contain a required number of switches to enable control of the motor drives and to control brightness change for each colour group of light emitting diodes. The control box may also contain an electronic circuit which allows all of the switching to take place from a remote location using wireless means of the kinds previously mentioned.

The control box may be weighted to provide stability of the whole assembly.

In summary, therefore, this invention in a preferred arrangement provides a lamp unit 1 suspended by a flexible connection 3, such as a cable or linkage, from an anchor block 4.

The anchor block 4 is rigidly attached to two flexible rods 7, 7a. The flexible rods are held parallel to each other at spaced locations along their length by means of a number of spacer blocks 8. The flexible rods form a natural arc by reason of the weight of the lamp unit 1. The rods are supported by a control box 2 and extend through a rigid tube 9. Each rod has an associated rack and pinion drive 10, 11. When the outermost rod is lengthened and/or the innermost arm is shortened the arc changes shape and causes the lamp unit 1 to lower. Conversely the lamp unit is raised when the outer arm is shortened and/or the innermost arm is lengthened. When both rods are moved synchronously the reach of the lamp increases or decreases.

Although the invention has been described herein in the context of a lamp assembly, the described assembly may be used for the support of any suitable load. Thus, in its broadest form, the invention extends to a support assembly comprising a load, a base and two flexible support members connecting the load with the base as described herein.

Claims

CLAIMS

1. A lamp assembly comprising a lamp housing, a base and two flexible support members connecting the lamp housing with the base, wherein: the support members are sufficiently rigid to support the lamp housing but capable of bending under load, such that the support members each form an arc, in use, with one support member radially outwardly of the other; a distal end of one support member is connected to an adjacent distal end of the other support member; and the length of at least one support member between the lamp housing and the base is variable independently of the length of the other support member between the lamp housing and the base to vary the radius of curvature of the arc.

2. A lamp assembly as claimed in claim 1, wherein the support members are substantially parallel.

3. A lamp assembly as claimed in claim I or 2, wherein the support members are spaced in the radial direction of the arc.

4. A lamp assembly as claimed in any preceding claim, wherein the support members are interconnected at their ends closest to the lamp housing.

5. A lamp assembly as claimed in any preceding claim, wherein the length of each support member between the lamp housing and the base is variable independently of the length of the other support member between the lamp housing and the base.

6. A lamp assembly as claimed in any preceding claim, wherein the lengths of the support members between the lamp housing and the base can be varied synchronously to vary the distance between the lamp housing and the base.

7. A lamp assembly as claimed in any preceding claim, wherein the lamp housing is mounted to hang under its own weight.

8. A lamp assembly as claimed in any preceding claim comprising a drive mechanism arranged to retract or extend the proximal end of at least one support member into or out of the base or the lamp housing to vary the effective length of the support member.

9. A lamp assembly as claimed in claim 8, wherein the drive mechanism is arranged to retract or extend the proximal end of at least one support member into or out of the base.

10. A lamp assembly as claimed in claim 8 or 9, wherein the drive mechanism comprises a pinion cooperating with a toothed rack operatively connected to the support member.

11. A lamp assembly as claimed in claim 8 or 9, wherein the drive mechanism comprises an axle operatively connected to a coiled portion of the support member.

12. A lamp assembly as claimed in any preceding claim, further comprising a heating device to vary the length of at least one support member between the lamp housing and the base by thermal expansion.

13. A lamp assembly as claimed in any preceding claim, wherein the support members are located within a flexible conduit.

14. A lamp assembly as substantially as described herein and exemplified with reference to the drawings. C)

Amendments to the claims have been filed as follows 1. A lamp assembly comprising a lamp housing, a base and two flexible support members connecting the lamp housing with the base, wherein: the support members are sufficiently rigid to support the lamp housing but capable of bending under load, such that the support members each form an arc, in use, with one support member radially outwardly of the other; an end of one support member is connected to an adjacent end of the other support member; and the length of at least one support member between the lamp housing and the base is variable independently of the length of the other support member between the lamp housing and the base to vary the radius of curvature of the arc.

2. A lamp assembly as claimed in claim 1, wherein the support members are substantially parallel.

3. A lamp assembly as claimed in claim I or 2, wherein the support members are spaced in the radial direction of the arc. * S * S S

4. A lamp assembly as claimed in any preceding claim, wherein the support members are interconnected at their ends closest to the lamp housing.

5. A lamp assembly as claimed in any preceding claim, wherein the length of each support member between the lamp housing and the base is variable independently of the length of the other support member between the lamp housing and the base.

6. A lamp assembly as claimed in any preceding claim, wherein the lengths of the support members between the lamp housing and the base can be varied synchronously to vary the distance between the lamp housing and the base.

7. A lamp assembly as claimed in any preceding claim, wherein the lamp housing is mounted to hang under its own weight. "1 \

8. A lamp assembly as claimed in any preceding claim comprising a drive mechanism arranged to retract or extend the proximal end of at least one support member into or out of the base or the lamp housing to vary the effective length of the support member.

9. A tamp assembly as claimed in claim 8, wherein the drive mechanism is arranged to retract or extend the proximal end of at least one support member into or out of the base.

10. A lamp assembly as claimed in claim 8 or 9, wherein the drive mechanism comprises a pinion cooperating with a toothed rack operatively connected to the support member.

11. A lamp assembly as claimed in claim 8 or 9, wherein the drive mechanism comprises an axle operatively connected to a coiled portion of the support member.

12. A lamp assembly as claimed in any preceding claim, further comprising a heating device to vary the length of at least one support member between the lamp housing and the base by thermal expansion.

13. A lamp assembly as claimed in any preceding claim, wherein the support members are located within a flexible conduit.

14. A lamp assembly as substantially as described herein and exemplified with reference to the drawings.