AU3749297A

AU3749297A - Filter belt guide

Info

Publication number: AU3749297A
Application number: AU37492/97A
Authority: AU
Inventors: David John Tebbutt
Original assignee: Scapa Group Ltd
Current assignee: Scapa Group Ltd
Priority date: 1997-09-11
Filing date: 1997-09-11
Publication date: 1999-03-25
Also published as: ZA987808B; WO1999012633A1

Description

.1 Regulation 3.2

AUSTRALIA

PATENTS ACT 1990 COMPLETE

SPECIFICATION

FOR A STANDARD PATENT

ORIGINAL

;i i i s ;i~irr i rrs* r r. r, t' i c- a i--;g i S Name of Applicant: SCAPA GROUP PLC Actual Inventor: David John Tebbutt Address for Service: MADDERNS, 1st Floor, 64 Hindmarsh Square, Adelaide, South Australia, Australia Invention title: FILTER BELT GUIDE The following statementis a full description of this invention, including the best method of performing itknown to us.

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i;i '9 FILTER BELT GUIDS This invention relates to guides for filter belts, for the purpose of guiding and centring filter belts of the kind with edge tracks provided by a bead provided on the edge of the belt.

Belts of this kind are for example used on rotary vacuum drum filters. The usual guide arrangement for the belt comprises a pair of wheels at each edge which contact the rubber bead or edge-track at an angle.

Sometimes problems arise as the wheels catch in the clipper seam used to join the ends of the filter belt to make it endless. Such catching affects the running of the machine, and damages the seam.

US Patent 3615023 discloses a centring or guiding device for a filter belt which exerts transverse tension in the belt, by means of pairs of glide sleeve members, engaging respective edge track beads on the edges of the belt, under tension urging the glide sleeves outwardly with respect to the belt. The glide shoes are in the form of cylindrical members extending parallel to the longitudinal direction of the belt and may be coated with a fluoropolymer to reduce friction. The cylindrical members do nothing to alleviate the.problem of catching the belt/seam, since they are simply cut straight at their ends.

An object of this invention is to provide a filter ,belt guide apparatus which enables guidan cntring of the belt to be carried out, but which is free of the -jm

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i i.: i:;t (jl:i: q risk of catching in the belt seam thereby avoiding the damage which can be caused thereby.

This invention accordingly provides, in an endless belt filtration machine, guide means for the filtration belt, mounted on the machine, and at each side of the intended push of the filtration belt, said guide means each comprising a pair of members, located each to bear respectively on upper and lower faces of an edge track bead on the respective edge of the belt, the members of each pair being formed at each end with means providing a guide surface merging with faces thereof which bear on the edge track faces.

Each member may be in the nature of a skid or ski member, with a curved surface forming a surface which bears on one of the said edge track bead faces, and 15 having a portion at each end which is bent out of the axis of the curved surface of the skid or ski member, away from the respective edge track bead face, thereby providing said merging guide surface.

Each member maybe carried on an L-shaped rod, the 20 other end which is mounted on a bracket. The bracket may have two leaves set at a right angle and mounted on the machine frame, each leaf carrying one of the L-shaped rods, with the leaves of the bracket straddling or S embracing the respective edge of the belt.

25 A preferred embodiment of filter belt guide Saccording to the invention will now be described, with reference to the accompanying drawings, wherein:-

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1 i i r ii J 3 Fig 1 is a general perspective view of a belt filtration machine provided with belt guides according to the invention.

Fig 2 is a sectional view of one edge region of the belt, showing the guides and their mounting means and Fig 3 is a perspective view of the guides at one belt edge.

A belt filtration machine comprises a drum 10, the lower part of which is immersed in a slurry vat 11, containing material to be filtered. A filter belt 12 extends about the drum, and at one side is guide off the i drum 10 to pass about a filtrate discharge roll 13, an roller guide roll 14, and a tensioning roll Guide assembles 16 are disposed one at each side of the belt 12, in the upper reach between the drum 10 and filtrate discharge roll 13. to centre and guide the belt.

One of the guide assembly 16 is shown in more detail in Figs 2 and 3. Each guide assembly comprises a pair of guide members 17,18. One such guide member is disposed above, and one below the edge of the belt 10, bearing on a respective upper inside surface 19 and lower made surface 20, of an edge track bead 21 connected to or formed on the 10. Each guide member comprises an Selongate rod of circular cross-section, providing a respective curved bearing surface 17a or 18a having an IV A axis of curative coinciding with the axis of the rod.

Each rod 17,18 is formed at each endwith a portion 17a, Si7b, 18a, 18b which is bent away from the edge track bead I 4 21, to provide at each bend a merging guide surface 22 so that each guide member take the form of a skid or ski member with up turned ends. The guide surfaces 22 ensure that there is no edge or stop presented to a raised feature on the belt such as a clipper seam joining the ends of. Thus the guides will not catch any such raised part, avoiding snagging or damage for jamming of the belt.

Guide number 17 is mounted on an L-shaped rod 23, whilst guide member 18 is symmetrically mounted on an Lshaped rod 24. The rods 23, 24 are directed towards the edge of belt 10, and are carried by means of screw and nut fastenings on respective leaves 25, 26 of a bracket, which is in turn mounted by a rod 27 to the frame of the 15 filter machine.

The guide members 17, 18 maybe varied from the embodiment described above, for example by being in the form of curved shoes with turned up or curved ends, or part-tubular members again with turned up ends. The merging guide surface may, at the very least, be provided by contouring or chamfering the ends of otherwise plain rods or shoes forming the guide members.

The guide members may of course be mounted in any manner desired, and may include springs or hydraulic F 25 means for varying the tension on the filter belt, or tensioning may be by means of screw and nut fastenings of the rods 23, 24 in the leaves of the bracket.

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Claims

1. In an endless belt filtration machine, guide means for the filtration belt, mounted on the machine and at each side of the intended edge location of the filtration belt, characterised in that said guide means each comprise a pair of members located to bear respectively on upper end and lower faces of an edge track bead on the S"respective edge of the belt, the members of each pair being formed at each end with means providing a guide S" surface merging with faces thereof which bear on the edge 10 track faces.

2. Guide means according to claim 1, wherein each member of each pair has a curved surface which is continuous with a surface which bears on one of the edge .track bead faces, and has a portion at each end which is 15 bent out of the axis of the curved surface of the member, I away from the respective edge track bead face, thereby providing said merging guide surface.

3. Guide means according to claim 1 or claim 2, wherein each member is carried on an L-shaped rod, the other end of which is mounted on a bracket comprising two leaves set at a right angle and mounted on the machine frame, Seach leaf carrying one of the L-shaped rods with the '1 leaves of the bracket straddling or embracing the S respective edge of the belt. i 25

4. Guide means according to claim 2, wherein each guide member comprises an elongate rod of circular cross- section providing a respective curved bearing surface 6 having an axis of curvature coinciding with the axis of the rod, and being formed at each end with a portion which is bent away from the edge track bead to provide at each bend a merging guide surface, to ensure that no edge or step is presented to the belt.

Guide means according to claim 2 in the form of curved shoes with turned-up or curved ends.

6. Guide means according to claim 2, comprising part tubular members with turned-up ends. 10

7. Guide means according to claim 2, wherein the merging guide surface is provided by contouring or chamferring the ends of otherwise plain rods or shoes i forming the guide members.

8. Guide means according to any preceding claim, 15 wherein the guide members are mounted on a rod.

9. Guide means according to any of claims 1 to 8, wherein the guide means are mounted on a mounting including springs or hydraulic means for varying the Stension on the filter belt.

10. Guide means according to any of claims 1 to 8, wherein the guide means are mounted on means including a screw and nut fastening for varying the tension on the filter belt. I Dated this 11th day of December 1997. 1 SCAPA GROUP PLC By its Patent Attorneys