AU718305B2 - Assembly line - Google Patents

Description

S F Ref: 366195

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name and Address of Applicant: Address for Service: Invention Title: ASSOCIATED PROVISIONAL [31] Application No(s) PN7925 Ronald E. Graham (Holdings) Pty. Limited 127-153 Rookwood Road Yagoona New South Wales 2199

AUSTRALIA

Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia Assembly Line APPLICATION DETAILS [33] Country

AU

[32] Application Date 6 February 1996 The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5815 Assembly Line Technical Field The present invention relates to assembly lines and more particularly but not exclusively to assembly lines to produce grating panels.

Background of the Invention Grating panels are manufactured from a "mat" to which there is attached various panel parts. Typically the fabrication will include welding of the parts to the panel.

The introduction of Forge welding enabled the rapid production of stock mats 10 employed in gratings. However the method of fabricating the grates basically remained *to0 unchanged. Essentially each grating was produced by a single person who initially was provided with a drawing of the grating to be produced. The drawing would list the various components as well as the mat size. The worker responsible for that grating would cut the components from lengths of raw materials and select the appropriate 15 panel. The materials were then taken to a work bench at which the grating was fabricated.

~In addition to the above the introduction of computer aided drafting enabled the rapid production of drawings and templates for different shaped gratings. The use of templates reduced the time taken to mark out various sizes and reduced the skill level required for the task to be performed.

Despite these advances in technology the old method of fabrication was still basically employed. Accordingly, producing gratings was reasonably slow and labour intensive.

Objection of the Invention It is the object of the present invention to overcome or substantially ameliorate the above disadvantages.

Summary of the Invention There is disclosed herein a production line comprising: a first conveyor; a second conveyor having its main direction of extension generally parallel and co-extensive with the first conveyor but transversely spaced therefrom; a parts delivery station at an upstream end portion of a first conveyor at which parts of an assembly are delivered to the first conveyor; a completed assembly station at a downstream end portion of the second conveyor to which completed assemblies are delivered by the second conveyor; [n:\libtt100843:JED 2 at least one mobile work bench assembly for assembling said parts to form a completed assembly, said mobile work bench assembly including a base frame, an upper work bench mounted on the base frame for height adjustment relative thereto and a plurality of horizontally extending tines, said mobile work bench assembly being located between the first and second conveyors and moveable there between in a transverse direction relative thereto, said first and second conveyors including gaps through which said tines pass to enable said mobile work bench assembly to remove said parts from the first conveyor and to deliver said completed assemblies to the second conveyor.

Brief Description of the Drawings Preferred forms of the present invention will now be described by way of example only with reference to the accompanying drawings; wherein Figure 1 is a schematic plan view of an assembly line; Figure 2 is a schematic side elevation of a mobile bench employed in the assembly line of Figure 1; ooo Figure 3 is a schematic top plan view of the bench of Figure 2; Figure 4 is a schematic end elevation of the bench of Figure 2;.

o: •Figure 4 is a schematic sectioned end elevation of the bench of Figure 2; Figure 5 is a schematic sectioned end elevation of the bench of Figure 2; Figure 6 is a schematic side elevation of a portion of a conveyor employed in the assembly line of Figure 1; and Figure 7 is a schematic top plan view of the conveyor portion of Figure 6.

Detailed Description of the Preferred Embodiment In the accompanying drawings there is schematically depicted an assembly line 10. The assembly line 10 includes a first conveyor 11 which is generally parallel and co- 000$ extensive with respect to a second conveyor 12. Located between the conveyors 11 and 12 are work stations 13. The conveyors 11 and 12 move in the direction of the arrows 14.

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[R:\LIBLL]09088.doc:MFF The conveyor I I at its upstream end is provided with a parts delivery station while the conveyor 12 at its downstream end is provided with a completed assembly station 16.

The receiving end 40 of the station 15 receives grating mats from a stock supply 17. The mats are cut by saw 41 to form grating panels. The grating panels are moved to the delivery end 42 of the station 15 together with other parts from a store 18.

Accordingly, the station 15 receives grating panels, parts, drawings and templates required to complete a grating. The material passes along the conveyor I I until it reaches one of the stations 13. At that station, a worker by employing the mobile work bench 19 removes the grating panel, parts, drawings and templates from the conveyor 11. The grating is assembled at the station 13 and the completed assembly delivered to the conveyor 14. Completed gratings are then delivered to the station 16 at which they are stacked and from which stacked gratings are despatched.

The mobile bench assembly 19 includes a base frame 20 provided with four wheels 21. The wheels 21 engage rails 22 which extend transversely between the 0 0 0 0 [RALIBI.L]09088.doc:NTF 3 conveyors 11 and 12. The base frame 20 includes hollow frame members 23 which are filled with ballast material 24 so that the base frame 20 is reasonably heavy and provides a low centre of gravity for the mobile work bench assembly 19.

Mounted on the base frame 20 is a hydraulic or pneumatic ram 25 having a piston 26 attached to an upper work bench 27 including three horizontal tines 28. The bench 27 is prevented from rotation about the longitudinal axis of the piston 26 by means of a pair of telescopically associated tubes 29. One of the tubes 29 is attached to the base frame 20 while the other tube is attached to the work bench 27. By actuation of the cylinder 25, the work bench 27 may be raised and lowered. If welding is to be performed on the work bench 27, an earth strap needs to be provided linking the bench 27 to the base frame 20. Each of the tines 28 would be supported by a post Each of the conveyors 11 and 12 would consist of conveyor modules 31. Each conveyor module would include an uninterrupted conveyor length 32 positioned remote from the station 13. The other conveyor length 33 would be positioned closest to the iooo station 13. The conveyor length 33 is not continuous, and consists of two conveyor portions 35 and two smaller portions 36 which define gaps 37. The gaps 37 are positioned and dimensioned so that the tines 28 may pass there through. The conveyor portions 36 are held by horizontal beams 38 in a cantilever lever manner. The conveyor lengths 32 and 33 are supported on pedestals 39.

In operation of the above described assembly line 10, the grating panels and parts are delivered to the station 15 wherefrom they are moved by the conveyor 11. A worker at any one of the station 13 will then remove the grating panel and its associated parts, drawings and templates by use of the work bench 19. More particularly, the work bench assembly 19 is positioned so that tines 28 are positioned basically below material passing along the conveyor 11. The rails 22 are positioned so the tines 28 are located beneath the gap 37. When the mat and its associated parts are positioned above the tines 28, the cylinder 25 is activated so that the tines 28 pass up through the gaps 37. Accordingly the tines 28 raise the material. Thereafter, the person at the work station 13 would move the work bench assembly 19 to a convenient work position so that other material may pass along the conveyor 11. Once the assembly job has been completed, the completed assembly is delivered to the conveyor 12 by the reverse operation in respect to the conveyor 11. That is, the tines 28 with the assembly located thereon, are moved so to be basically above the conveyor 12. Thereafter, the cylinder is operated so that the tines 28 are lowered and passed down through the gaps 37.

The completed assembly is then supported by and is moved along the conveyor 14 to the station 16.

[n:\libtt]OO843:JED

Claims (4)

1. A production line comprising: a first conveyor; a second conveyor having its main direction of extension generally parallel and co-extensive with the first conveyor but transversely spaced therefrom; a parts delivery station at an upstream end portion of a first conveyor at which parts of an assembly are delivered to the first conveyor; a completed assembly station at a downstream end portion of the second conveyor to which completed assemblies are delivered by the second conveyor; at least one mobile work bench assembly for assembling said parts to form a completed assembly, said mobile work bench assembly including a base frame, an upper work bench mounted on the base frame for height adjustment relative thereto and a plurality of horizontally extending tines, said mobile work bench assembly being located between the first and second conveyors and moveable there between in a transverse 15 direction relative thereto, said first and second conveyors including gaps through which 0 •said tines pass to enable said mobile work bench assembly to remove said parts from the 0first conveyor and to deliver said completed assemblies to the second conveyor. 0:00

2. The production line of claim 1, wherein said upper work bench is supported on a hydraulic or pneumatic ram mounted on said base frame, and said mobile o 20 work bench assembly includes means to prevent relative rotation of the upper work bench with respect to the base frame about the longitudinal axis of the ram.

3. The production line of claim 1 or 2, wherein the base frame is weighted so as to provide the mobile work bench assembly with a low centre of gravity.

4. A production line substantially as hereinbefore described with reference 00o* 25 to the accompanying drawings. Dated 17 January, 2000 S" Ronald E. Graham (Holdings) Pty. Limited Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON 0o Soeso [R:\LIBLL]09088.doc:MFF