GB2213806A

GB2213806A - Article chute

Info

Publication number: GB2213806A
Application number: GB8729973A
Authority: GB
Inventors: Cetin Bilal Elmas; David Tolond
Original assignee: Post Office
Current assignee: Post Office
Priority date: 1987-12-23
Filing date: 1987-12-23
Publication date: 1989-08-23
Also published as: GB8729973D0

Abstract

A spiral chute comprises a helical floor member 1 which itself comprises an inner floor part 2 which is horizontal or slopes slightly upwardly in the outward direction, in cross-section, and a more steeply sloping outer part 3. The floor member 1 extends inwardly to the centre of the chute. <IMAGE>

Description

IMPROVED ARTICLE CHUTE This invention relates to article chutes.

A known chute of the present applicants consists of a central post and a helical floor wound around the post, the floor terminating at its outer edge in a peripheral side wall. In use, the chute is of course disposed with the post in a substantially upright position. Furthermore, in this known design of the applicants, the floor of the chute consists of an inner part which is horizontal or slopes slightly upwardly away from the post and an outer part which slopes away from the inner part more steeply than the inner part, this overall floor shape being determined mathematically for given applications to ensure that the articles descend down the chute at a constant velocity or at least under conditions in which their velocity does not exceed a given maximum without in general contacting the peripheral side wall.

Articles of differing coefficients of friction with the surface of the floor will in general occupy differing radial positions on the chute and in fact in the case of certain items with a high coefficient of friction, the articles will travel very close to or will even touch, the central post. Any contact of the article with the post interferes of course, with the passage of the article down the chute creating a hindrance to succeeding articles and causing the chute to become jammed or blocked. The chute may not self start once the blockage is removed.

Accordingly, the present invention provides a spiral article chute including a helical floor member having a substantially upright axis in use and comprising an inner part which is horizontal or slopes slightly upwardly in the outward direction and an outer part which slopes more steeply in the same direction, in which the floor member extends inwardly to the centre of the chute.

Preferably the floor parts merge in a curve to which they are tangential. The outer floor part may terminate in a peripheral wall which is substantially upright in use of the chute.

The chute may be provided with a surrounding support framework or alternatively a surrounding cylindrical support structure.

The floor member may be constructed in sections, preferably comprising 900 or 1800 sections.

The sections may be joined along a flange and support lugs may be secured to these flanges to provide a means of supporting the floor.

The chute may be manufactured in any suitable material, glass reinforced plastics material being preferred, though formed plastics material and sheet steel are satisfactory alternatives.

One embodiment of the invention will now be described, by way of example, with reference to the accompanying drawing.

Referring to the drawing, which shows the chute in a position for use, the chute comprises a helical floor member 1 having a substantially upright axis and consisting of an inner part 2 which is horizontal or slopes slightly upwardly away from the centre of the chute and a more steeply sloping outer part 3, the parts 2 and 3 merging in a curve to which the parts are tangential. Furthermore, the part 3 terminates in a side wall 4.

The floor and wall which is a one piece moulding of glass reinforced plastics material is made in 900 sections and successive sections are secured together along a flange 5. The chute also comprises lugs 6 secured to these flanges for a purpose to be described later.

To allow articles to be fed onto the chute, the latter includes an entry section 7 and to allow discharge of the articles from the chute at the lower end, the chute includes an exit section 8, this latter leading to an exit table 9.

The shape or contour of the floor is determined mathematically for specific applications of the chute to ensure that the articles for which the chute is designed, descend down the chute at a constant velocity or at least do not exceed a given maximum velocity, without in general touching the side wall.

It will be seen that the inner floor part 2 extends to the centre of the helix defined by the floor, that is to say the chute does not include any centre post or pole to support the floor of the chute.

Whilst in some cases, the strength of the floor could be such that the chute is self supporting in which case a suitable base will be provided, the chute will generally require auxiliary support and for this reason the lugs 6 in the present example, are provided. These may be attached to a supporting framework conveniently adjacent a building or other structure or possibly the lugs may be attached to a surrounding tubular support structure which could if desired replace the side wall 4, being itself made in sections as necessary to facilitate manufacture. In some instances, especially where a continuous cylindrical support structure is provided, the lugs may be dispensed with.

The purpose of extending the floor to the centre of the chute is to enable the full width of the floor to be available for the articles without the presence of a post to which articles in certain circumstances, depending upon their coefficient of friction with the floor surface, may come into contact.

Claims

CLAIMS:

1. A spiral article chute including a helical floor member having a substantially upright axis in use and comprising an inner part which is horizontal or slopes slightly upwardly in the outward direction and an outer part which slopes more steeply in the same direction, wherein the floor member extends inwardly to the centre of the chute.

2. A chute as claimed in Claim 1, wherein the floor parts merge in a curve to which they are tangential.

3. A chute as claimed in Claim 1 or 2, wherein the outer floor part terminates in a wall which is substantially upright in use of the chute.

4. A chute as claimed in Claim 1, 2 or 3 and provided with a surrounding supporting framework.

5. A chute as claimed in Claim 1, 2 or 3 and provided with a surrounding cylindrical support structure.

6. A chute as claimed in any one of Claims 1 to 5, wherein the floor member is constructed in sections.

7. A chutes as claimed in Claim 6, wherein the sections are angular sections.

8. A chute as claimed in Claim 7, wherein the sections are 900 sections or 1800 sections.

9. A chute as claimed in Claim 6, 7 or 8, wherein the successive sections are joined along a flange.

10. A chute as claimed in Claim 9 and including lugs secured to the flanges to provide a means of supporting the floor.

11. A chute as claimed in any preceding claim and manufactured of moulded glass reinforced plastics material.

12. A chute as claimed in any of Claims 1 to 10 and manufactured of formed platics material.

13. A chute as claimed in any of claims 1 to 10 and manufactured of sheet steel material.

14. A spiral article chute substantially as hereinbefore described with reference to the accompanying drawing.