AU645789B2 - Manhole scaffolding unit - Google Patents

Description

645789 COMMONWEALTH OF AUSTRALIA Patents Act 1952 COMPLETE SPECIFICATION (Original) FOR OFFICE USE Application Number: PJ9485 Class Int. Class Lodged: 05/04/90 Complete Specification Lodged: Accepted: Published: Priority: Related Art: TO BE COMPLETED BY APPLICANT Name of Applicant: CRAIG HAMILTON McROBERT 4 Address of Applicant: 0 29 Linden Way, Forrestfield, in the State of Western S Australia, Commonwealth of Australia.

Actual Inventors: CRAIG HAMILTON McROBERT Address for Service:- Wray Associates Primary Industry House 239 Adelaide Terrace Perth Western Australia 6000.

Complete Specification for the invention entitled: "MANHOLE SCAFFOLDING UNIT" The following statement is a full description of this invention, including the best method of performing it known to us:- P 005830 050491 P 005830 O504£I 2 THIS INVENTION relates to a scaffolding unit for utilisation in a space against a side wall.

In a confined space such as a vertical manhole, it can be difficult to use conventional scaffolding to carry out operations on the side wall defining the confined space.

The object of this invention is to provide a scaffolding unit which can be readily erected in a confined space to facilitate work or some other operation on the side wall and which can be readily dismantled and transferred to another site.

In one form the invention resides in a scaffolding unit for use in a space adjacent a wall, said scaffolding unit comprising a central column adapted to be supported within said space, and a plurality of platforms; said scaffolding having mounting means for mounting said platforms in spaced I positions on said column, and each said platform having stabilising means projecting from the periphery thereof and adapted to bear against said wall.

There are many situations where a scaffolding unit according to the invention would be advantageous, one being in vertical manholes and another being in vessels and chambers where work is to be carried out on the interior of the side wall thereof. Where the space is generally S"circular in plan, the side wall of the space is generally continuous and where the space is polygonal in plan, the side wall comprises a plurality of side wall sections.

Preferably, said stabilising means are adjustable.

3 Preferably, said column comprises a plurality of sections adapted to be coupled together in end to end relationship.

Conveniently said sections are coupled together by way of joining members.

Preferably, each platform is provided with an access means to provide access through said platform. The access means may comprise an access opening in said platform and a closure member for selectively closing said access opening. Said closure member may comprise a section of said platform, said section being removable to expose said access opening. Conveniently, said removable section is hinged to the platform for movement between an open position in which said access opening is exposed and a closed position in which said access opening is closed by said section.

Preferably, each of said platforms is demountable. In this regard, each of said platforms preferably comprises a frame structure having assembled and collapsed conditions and a deck structure mounted on the frame structure when the latter is in the assembled condition.

Preferably, said frame structure comprises a plurality of frame elements projecting outwardly from said column when said frame structure is in said assembled condition.

In one arrangement, each of said frame elements may be adapted to be releasably mounted onto said column so as to project outwardly therefrom. In another arrangement, each of said frame elements may be pivotally mounted onto said column for movement between assembled and collapsed conditions, and wherein retaining means are provided for releasably retaining said frame element in said assembled condition. Said retaining means may comprise a removable 4 brace which can extend between said frame element and said column or between said frame element and a lower portion of the scaffolding unit or some other rigid surface such as the floor of the space.

Preferably, said deck structure comprises a plurality of sections which can be assembled to define the platform.

The invention will be better understood by reference to the following description of several specific embodiments thereof as shown in the accompanying drawings in which: Figure 1 is a schematic side view of a scaffolding unit according to the first embodiment installed on a vertical manhole; Figure 2 is a fragmentary perspective view of the scaffolding unit of Figure 1; Figure 3 is a fragmentary perspective of a column forming part of the scaffolding unit of the first embodiment; Figure 4 is a fragmentary perspective view of a section of a frame structure forming part of the scaffolding unit of S the first embodiment; *O Figure 5 is a side view showing the section of the frame structure mounted on the column; Figure 6 is a schematic view of a scaffolding unit 0: according to a second embodiment; Figure 7 is a plan view of the scaffolding unit of the second embodiment; Figure 8 is a schematic side view of the scaffolding unit of the second embodiment; Figure 9 is a fragmentary view showing the pivotal o:•o connection between the frame structure and the column of the scaffolding unit of the second embodiment; Figure 10 is a schematic side view of a scaffolding unit according to a third embodiment; 5 Figure 11 is a schematic perspective view of a scaffolding unit according to the second or third embodiment; and Figure 12 is a schematic plan view showing the supplementary platform section of Figure 11 fitted in position.

The embodiment shown in Figures 1 to 5 of the accompanying drawings is directed to a scaffolding unit to be used in vertical manholes where the :nterior surface of a vertical manhole is to be lined with plastic. There is a need scaffolding structure which can be readily erected in the confined space within the vertical manhole so that the lining operation can be readily carried out, and which can be readily dismantled and transferred to another manhole following completion of the lining operation. The scaffolding unit 10 according to the first embodiment can satisfy such a need.

In the drawings the manhole is identified generally by reference number 11 and comprises a vertical side wall 12 and a floor 13.

20 The scaffolding unit 10 according to the first embodiment comprises a central column 14 which is formed of sections of tube connected togethsr in end to end relationship by joining members 15. The bottom end of the column 14 is provided with a base plate 16 which rests on the floor of the manhole.

A plurality of demountable platforms 17 are mounted at spaced positions on the column. Each platform 17 is provided with a plurality of stabilising means 19 which project laterally from the periphery of the platform for engagement with the wall 12 of the manhole.. The stabilising means 19 are adjustable so that they can bear 6 against the wall of the manhole and so provide lateral stability to the scaffolding unit. Where thle manhole is rectangular when viewed in plan, there would conveniently be two such stabilising means 19 adapted for engagement with a pair of opposed corners of the manhole. In such a situation, each stabilising means 19 would comprise an engaging member 21 having a pair of engaging faces 23 each adapted to bear against one of the side wall sections of the manhole which meet to define the corner at which the stabilising means is located.

Each platform 17 comprises a frame structure 25 and a deck structure 27. The platform is formed in two sections 17a and 17b. The sections 17a and 17b have an assembled condition in which they are mounted on the column and cooperate to define the platform, and a collapsed condition in which they are detached from the column for convenience of handling during assembly and dismantling of the scaffolding unit, and during transportation and storage oo S thereof "2 r The frame structure comprises a plurality of frame elements 29 adapted to project laterally from the column when the platform is in the assembled condition.

In this embodiment, the frame structure is formed in two sections 25a and 25b, on corresponding to each of the platform sections 17a and 17b. Each frame section comprises an inner member 33 which defines two of the frame elements 29 and on which there are mounted a pair of lugs in spaced apart relationship to define a gap 37 in which the column can be received. Each frame section 25 also comprises lower engaging means 36 defining a further gap 38 for receiving the column.

7- Each section 25 of the frame structure is adapted to engage with a respective supporting member 41 mounted on the column. The supporting member 41 comprises two plates 42 each having ends which extend beyond opposed faces of the column such that each lug 37 can e:igage the space between the plates when the platform is lowered onto the column thereby to lock the platform in the desired position on the column, as shown in Fig Each platform has a removable section 43 which is hinged at 45 for movement between an open condition in which exposes an access opening in the platform and a closed condition in which the access opening is not exposed. The access opening allows an operator to move between two adjacent platforms with the assistance of a ladder.

Each platform is preferably shaped to conform to the cross sectional shape of the manhole which in some instances may be rectangular ard in other instances may be circular.

The scaffolding unit according to the first embodiment can be readily installed in the confined space within a manhole 30 to provide various levels at which an operator can work, and which can be readily dismantled and transferred to another site following completion of work in the manhole.

The column is formed in various sections to facilitate its handling as it each platform which in this embodiment is in two sections.

e Because of the constructions of the scaffolding unit according to the first embodiment, there is a limit to the lateral size to which it can be made. There is a need for a scaffolding unit which can be used in larger confined spaces such as in vertical chambers, vessels, columns and smokestacks, and the scaffolding unit according to the 8 second embodiment, which is shown in Figures 6 to 9 has been devised for such purposes.

In the drawings such a confined space is identified generally by reference number 51 and comprises vertical side wall 52 and a floor 53.

The scaffolding unit 50 according to the second embodiment comprises a central column 54 formed of a plurality of sections of tube connected in end to end relationship by joining members 55. A base plate 56 is provided at the bottom of the central column 54.

A plurality of demountable platforms 55 are mounted on the central column 54. Each of the platforms 55 comprise a frame structure 57 and a deck structure 59. The frame structure is movable between assembled and collapsed conditions and supports the deck structure 59 when in the assembled condition. The frame structure 57 comprises a plurality of frame elements 61 which project laterally from the column. Each frame element 61 is pivotally mounted at one end on the column by way of a pivot pin 63. The pivot.

1..20 pin 63 is supported on a central pivot member 65 mounted on the column. With this arrangement, the frame element can pivot between the assembled condition in which it extends laterally of the column and the collapsed position in which it extends generally alongside the column.

A stabilising means 66 is mounted on the free end of the column. The stabilising means 66 is adapted to bear against the wall 52 of the confined space 51 in which the scaffolding unit is to be assembled. The stabilising means is adjustable for this purpose and this embodiment 9 comprises a block 67 having an outer face for engagement with the side wall 52 of the space. The block 67 is mounted on a shaft 69 which is in threaded engagement with the frame element whereby the lateral positior of the outer face with respect to the frame element can be varied upon rotation of the shaft.

The frame structure includes diagonal bracing members 71 which are removably mounted between the frame elements.

The diagonal bracing members can be mounted onto the frame elements in any suitable fashi i.

The deck structure 59 comprises a plurality of .ections 73 which can be located on the frame structure when the latter is in the assembled condition. Each section of the deck comprises a peripheral frame 75 and a covering 77 mounted on the peripheral frame. In this embodiment the covering is in the form of a mesh material.

Stabilising means 79 are provided for engagement between adjacent sections of the deck structure to maintain the sections in stable relationship. In this embodiment, one of 'he stabilising means is mounted on each section for engagement with an immediately adjacent deck section.

An access opening 81 is provided in each platform. The access opening 81 comprises a hole formed in one of the deck sections, and a closure 85 is provided for selectively closing the access opening for safety. As with the first 9t* embodiment, the closure 85 can be defined by a section of a the platform which is pivotally mounted for movement between open and closed positions.

Retaining means 91 are provided for retaining the frame structure in the assembled condition. In this embodiment 10 the retaining means 91 comprises a brace which supports each frame element 61 in the assembled condition. With the exception of the lowermost brace which supports the lowermost frame structure 57, each brace 91 extends between the frame structure which it supports and the platform immediately below it. The brace is supported at its ends in sockets 95 which receive and retain the brace in place.

The lowermost brace has a base plate 97 which bears on the floor 53 of the confined space and which is linked to the base 56 of the central column 54 by way of a rigid member 99.

With the construction of the scaffolding unit according to the second embodiment, the various components of the unit can be readily assembled and dismantled in a confined space 51. The central column 54 and various platforms are progressively assembled in an upward direction until the entire structure has been completed. Working operations can then be performed on the various levels defined by the S platforms. Following completion of the working operations, the scaffolding unit can be disassembled aind trarnsferred to another site.

S" The third embodiment which is shown in Figure 10 of the drawings is similar to the second embodiment with the exception that the braces 91 each extend between the respective frame structure 57 and the column 54 rather than between the various platforms and between the lowermost platform and the floor of the space.

The second and third embodiments have been described in S relation to a scaffolding unit for a confined space which is generally circular in plan. In circumstances where the confined space is of some other shape such as rectangular, 11 supplementary platform sections 101 (Fig 11) can be utilised to fill gaps which exist between the circular platform and the rectangulir side wall of the confined space. The supplementary platform sections 101 are shaped generally to conform with the gap to be filled and are each adapted to be releasably mounted on the platform. For this purpose, each iupplementary section 101 has mounting pins 103 which are receivable in complementary sockets mounted on the platform 55. The supplementary sections also have adjustable stabilising means 105 for engaging the side wall of the confined space to assist in stabilising the scaffolding unit.

It should be appreciated that the scope of the invention is not limited to the scope of the embodiments described. It should also be appreciated that the scaffolding unit can be used in any space defined by a side wall where the stabilising means can engage the side wall for the purpose of stabilising the scaffolding unit.

*e r

Claims (12)

1. A scaffolding unit for use in a space adjacent a wall,, said scaffolding unit comprising a central column adapted to be supported within said space, and a plurality of platforms, said scaffolding unit having mounting means for mounting said platforms in spaced positions on said column, and each said platform having stabilising means projecting from the periphery thereof and adapted to bear against said wall.

2. A scaffolding unit according to claim 1 wherein said stabilising means are adjustable.

3. A scaffolding unit according to claim 2 wherein said column comprises a plurality of sections adapted to be S" coupled together in end to end relationship.

4. A scaffolding unit according to any one of the i preceding claims wherein each platform is provided with access means to provide access through said platform.

5. A scaffolding unit according to any one of the preceding claims wherein each of said platforms is demountable.

6. A scaffolding unit according to claim 5 wherein each of said platforms comprises a frame structure having assembled and collapsed conditions and a deck structure mounted on the frame structure when the latter is in the assembled condition.

7. A scaffolding unit according to claim 6 wherein said frame structure comprises a plurality of frame elements projecting outwardly from said column when said frame Sstructure is in said assembled condition. 13

8. A scaffolding unit according to claim 7 wherein each of said frame elements is adapted to be releasably mounted onto said column so as to project outwardly therefrom.

9. A scaffolding unit according to claim 7 wherein each of said frame elements are pivotally mounted onto said column for movement between assembled and collapsed conditions, and wherein retaining means are provided for releasably retaining said frame element in said assembled condition.

A scaffolding unit according to claim 9 wherein said retaining means comprises a removable brace.

11. A scaffolding unit according to any of claims 6 to wherein said deck structure comprises a plurality of sections.

12. A scaffolding unit substantially as herein described with reference to the accoinpanying drawings. SDATED this NINETEENTH day of NOVEMBER 1993. *ppppp CRAIG HAMILTON McROBERT Applicant Wray Associates Perth, Western Australia Patent Attorneys for the Applicant 1 7$ -py