EP0925127A2

EP0925127A2 - Strip shaping mechanism

Info

Publication number: EP0925127A2
Application number: EP97939019A
Authority: EP
Inventors: John Christopher Acorn Engineering Ltd NORKETT
Original assignee: Acorn Engineering Guilford Ltd
Current assignee: Acorn Engineering Guilford Ltd
Priority date: 1996-09-05
Filing date: 1997-09-04
Publication date: 1999-06-30
Also published as: GB2316897A; GB2316897B; GB9618479D0; AU4125197A; WO1998009744A2; WO1998009744A3

Abstract

The application describes apparatus for concave shaping metal strip (3) which passes the strip through a set of rolls (8, 9) at which appropriate concave shaping is applied to the strip (3) by means of a shaping set of rolls; wherein the strip is supported in its passage through the roll set by means of a flexible supporting member (4), whereby to ensure that the strip is subject to the shaping process along the total passage thereof through the shaping set of rolls (8, 9). The supporting member can be a belt (4) or web, and can be continuous. The device is particularly useful for shaping reflective louvres for use in fluorescent lamp fittings.

Description

STRIP SHAPING MECHANISM

This invention relates to strip shaping mechanism, and is especially

applicable to shaping mechanisms associated with a processing machine

such as a press stamping machine where the shaping mechanism processes

a strip product in association with strip feeding and press stamping

machinery with one or more stamping actions to produce any one of a range

of a particular product from the shaped strip material.

Thus, for example, such a strip shaping mechanism may well be used

for the shaping of strip formed of light metal alloy in association with a press

stamping machine where the light metal alloy strip is sequentially stopped

and stamped at a number of stamping stations within the machine ready for

further fabrication to constitute eventually reflective and separating louvres for lighting installations.

Such louvres require in general a lower facing concave curved shaping

transverse to the length thereof below which is disposed an elongate lighting

source, and which is usually provided by passing the strip metal transversely

to its length through a roll set of three or more rolls to provide the necessary

curvature to ensure, in the final product, such a concave reflective surface

above the elongate (typically fluorescent) lamp to reflect the light directed

from the upper surface of the louvre down to the room or office space

located therebelow, to maximise for any given light source the illumination

of that office or room space.

Amongst the problems associated with such apparatus for providing

a concave curved surface to the strip intended for such overhead lamp

louvres, is that, because of the very nature of a three roll system, for

example, frequently used to provide such concave shaping, the lateral end

areas of the louvres tend to end up planar because the rolls are unable to

provide a concave surface to the end portion thereof, the rolls not being able

to be subject lateral ends to the curve-creating force of the three rollers, by

their very nature and disposition.

It is an object of the present invention to overcome or at least substantially reduce the above mentioned problem. In accordance with one aspect of the invention there is provided

apparatus for concave shaping metal strip including passing the strip through

a set of rolls at which appropriate concave shaping is applied to the strip by

means of a shaping set of rolls; wherein the strip is supported in its passage

through the roll set by means of a flexible belt-like member, whereby to

ensure that the strip is subject to the shaping process along the total

passage thereof through the shaping set of rolls.

In accordance with another aspect of the invention there is provided

a method for concave shaping metal strip including passing the strip through

a set of rolls at which the concave shape is applied to the strip wherein the

strip is supported in its passage through the roller set by means of a flexible

belt-like member, whereby to ensure that the strip is subject to the shaping process along the total passage thereof through the shaping set of rolls.

The flexible belt-like member may be of a continuous nature.

The roll set may comprise three rolls, two of the rolls being provided

for horizontally aligned parallel rotation, and the third opposed and parallel

to the other rolls, applied into the gap between the first and second rolls just

above mentioned such that the passage of the strip together with its supporting member are subject to a deflection by the rolls and a concave

forming motion. By means of the invention, a concave transverse configuration to the

strip, such as to be of the required nature for a concave reflective lamp

louvre is provided, the association of the supporting member with the strip

ensuring that the appropriate shaping of the latter is fully accomplished in

its passage through the roll set, since the supporting member prevents a

flattening motion of the strip as it passes out of the roll system.

The supporting member may comprise a belt or a web-like member.

Bearing in mind that louvres to be formed from metal strip may be of

a length of two metres or more, it will be appreciated that the web or belt,

together with the associated apparatus for subjecting the strip to a concave

configuration may be of very substantial width capable of accommodating

such a length.

The concavity provided by the roll set may, in accordance with

appropriate optical requirements, be varied during the transport of the strip

through the shaping set of rolls by ensuring that the roll applied between the

two fixed rolls, can be varied between different sets of metal strips to be

shaped, and indeed during the passage of a single strip therethrough. Thus,

the configuring mid-roller may be capable of movement into and out of the

gap between the two supporting rolls during the passage of a single strip to

provide, if desired, a complex concave configuration appropriate for the final

requirement with respect to the reflecting lamp louvre for which the strip is being prepared.

In order that the invention may be more readily understood one

embodiment thereof will now be described by way of reference to the

accompanying drawings in which:

Figure 1 is a schematic side elevation of strip shaping apparatus in

accordance with the invention;

Figure 2 is an enlarged schematic view of the overhead cam

arrangement controlling the mind roll of the control set; and

Figure 3 shows in an enlarged view the controlling roll and its

adjustability.

Referring to the schematic drawings herewith, there is illustrated a

machine for providing a downwardly directed (in use) concave reflective surface to highly polished strip aluminium alloy for use as a transverse or

overhead louvre member for a fluorescent lamp (for example) . Such metal

strip may be, for example, up to two metres in extension to match a

fluorescent lamp disposed in use therebelow, and the machine illustrated

herewith is intended to provide an appropriately shaped concave

configuration of full width to the surface of that reflective louvre for

subsequent disposition above the light source. The apparatus in accordance with the invention in principle comprises

a frame assembly 1 having a roller conveyor 2 disposed along the upper side

thereof bringing to the assembly strip metal 3 ready for appropriate concave

shaping.

On reaching the assembly on the roller conveyor, each individual strip,

which may, as hereinbefore mentioned, be up two metres in its longitudinal

configuration, is engaged by a continuous flexible belt 4 of equivalent width

(formed of reinforced PVC for example) and moves towards a shaping

portion 5 of the assembly. The strip 3 passes beneath a sequence of shot

bolt solenoids 6 (or alternatively switch operated stopping assemblies)

spaced across the machine and located above a fixed plate 7 which locate

the leading and trailing edge of the strip 3 and therefore provide signals to

the operating mechanism of the shaping portion 5

After passing through the shot bolt solenoids 6, each individual strip,

supported by the flexible belt 4 passes through a roller assembly comprising

two lower rollers 8, 9 freely rotating about parallel horizontal axes and

supported by a roller support 10 from a portion of the frame assembly 1 . In addition the strip passes beneath an overhead roller arrangement 1 1

supported on an overhead roller support 1 2 and an appropriate vertically

disposed slide beam 1 3 movable with respect to a fixed portion 14 of the

beam frame by means of linear beam bearings. Movement of the roller

support 12, 1 3 and the overhead roller 1 1 is provided, from a motor 1 6 dictated by the shot bolt solenoids 6, with a driving motion such that a cam

1 7, supported on a cam support 1 8, rotates and, via a cam follower 1 9,

moves the overhead roller somewhat into the gap between the two

underlying rollers to provide the necessary force on the strip as it passes

therebeneath, supported by the belt, to shape, in accordance with the

configuration of the cam, the necessary concave configuration to the upper

surface of the strip for the required eventual reflective louvre configuration

of the product concerned. Adjustment of the cam follower 1 9 and the

overhead roller 1 1 is provided by set screws 20 and 21 respectively.

It is to be appreciated that the continuous belt 6 is driven by roller 22,

passes over a lower roller 24 and an idler roller 25, and is tensioned by

means, in the arrangement illustrated, of a spring urged slide 23 and the

lower roller 24 to ensure appropriate tension of the flexible belt in its support

of the strip as it passes through the shaping apparatus, thereby ensuring full

concave shaping across the whole of the strip as it passes through the

shaping portion 1 1 .

The shot bolt solenoid control arrangement associated with the

shaping mechanism is of importance in that it can be arranged to control the

movement and speed of movement of the belt 6 and therefore the strip 3

passing through the shaping portion 1 1 , and can also be arranged to control

the cam follower 1 9 in association with the cam 1 7 to provide the

appropriate shaping for the strip as it passes therethrough, and indeed can ensure an appropriate speed of operation of the apparatus such that the

apparatus can operate at a rate, so we have discovered, of shaping of the

strip of, say, two metres width, during a passage lasting only two seconds

through the machine. Such speed of operation manifestly enables a most

competitive rate of shaping enabling rapid production of shaped strip for use

in concave louvre products.

It is to be appreciated that along a strip of some two metres

elongation, there may be provided up to a total, for example, twelve shaping

roller sets to ensure accurate rolling of the total strip.

It is to be understood that the foregoing is merely exemplary of

apparatus for shaping metal strip and methods for accomplishing same in

accordance with the invention and that modifications can readily be made

thereto without departing from the true scope of the invention.

Claims

1 . Apparatus for concave shaping metal strip adapted to pass the strip

through a set of rolls at which appropriate concave shaping is applied

to the strip by means of a shaping set of rolls, comprising a flexible

supporting member adapted to support the strip in its passage

through the roll set, whereby to ensure that the strip is subject to the

shaping process along the total passage thereof through the shaping

set of rolls.

2. Apparatus according to claim 1 wherein the supporting member

comprises a belt or a web-like member.

3. Apparatus according to claim 2 wherein the belt or web-like member

is of a continuous nature.

4. Apparatus according to any preceding claim wherein the roll set

comprises three rolls, two of the rolls being provided for horizontally

aligned parallel rotation, and the third opposed and parallel to the

other rolls, applied into the gap between the first and second rolls

such that during passage the strip and supporting member are subject

to a deflection by the rolls and a concave forming motion.

4. Apparatus according to claim 3 wherein the third roller is capable of movement into and out of the gap between the first and second rolls

during the passage of a single strip to allow a complex concave

configuration to be applied to the metal strip.

5. A method for concave shaping metal strip including passing the strip

through a set of rolls at which the concave shape is applied to the

strip, wherein the strip is supported in its passage through the roller

set by means of a flexible supporting member, whereby to ensure that

the strip is subject to the shaping process along the total passage

thereof through the shaping set of rolls.

6. Apparatus for shaping strip substantially as herein described with

reference to and/or as illustrated in the accompanying drawings.

7. A method of shaping strip substantially as herein described with

reference to and/or as illustrated in the accompanying drawings.