AU728793B2 - A clamp - Google Patents

Description

P/00/01i1 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: "A CLAMP" The following statement is a full description of this invention, including the best method of performing it known to us:

TITLE

"A CLAMP" FIELD OF THE INVENTION THIS INVENTION relates to a clamp and, in particular, a clamp for securing a plurality of adjacent planks disposed on a supporting framework.

BACKGROUND OF THE INVENTION Generally, workmen such as builders, electricians, painters and the like, are required to work at substantive heights above a ground level or floor of a building. Accordingly, in order to work at such heights, these workmen generally employ temporary supporting frameworks including scaffolding, trestles and the like.

In regard to trestles, a single horizontal plank, such as, for example, a solid timber or fabricated aluminium plank, is commonly disposed between a pair of ladder-like support frames. However, the width of such a plank, typically 250 mm wide, does not provide for a sufficiently safe support surface.

Accordingly, in order to increase the width of the support surface upon which a workman stands or walks on, a pair of adjacent 20 planks arranged in parallel has generally been used between support *o frames to form an elevated platform. In such arrangements, aluminium planks are generally not combined with timber planks because of their different inherent properties. In the case of aluminium planks, the planks are substantially rigid and lightweight having, typically, a thickness of 50 mm. In the case of timber planks, the planks are flexible having a thickness typically in the range of 40 mm to 60 mm and are substantially heavy in comparison to aluminium planks.

Having regard to the above, although a pair of adjacent planks arranged in parallel provides a wider support surface relative to a single plank, such an arrangement can create a number of problems that may jeopardise the safety of a workman standing or walking thereon. For 3 example, when a workman walks between such a pair of adjacent planks, one of these planks can be displaced sideways away from an adjacent plank. As a result, the stability of the surface upon which a workman operates is substantially compromised and may potentially cause the workman to lose balance and possibly fall causing injury.

Furthermore, in regard to platforms comprising a pair of timber planks, these planks typically have different degrees of flexibility relative to each other and, as such, when a workman stands or walks over the planks, one of these may be displaced downwardly relative to an adjacent plank. Consequently, a side wall of the adjacent plank may become exposed which may potentially cause the workman to trip over and possibly cause injury.

Unfortunately, such injuries occur on a frequent basis generally causing an injured workman to spend a considerable period of time in rehabilitation and out of the work force. In some cases, the injuries caused to a workman may be so severe that the workman may not be able to ever resume normal work tasks.

Other disadvantages associated with such workplace injuries are substantive medical/paramedical costs which are incurred 20 generally by insurance providers and worker's compensation schemes.

The extent and frequency of such workplace injuries also impacts on insurance and worker's compensation premiums.

Furthermore, in order to maintain normal operations at a specific work site, an employer may need to replace an injured workman by employing another person which may be a time consuming and costly process.

Accordingly, in the interests of improved workplace, health and safety, a solution is required to alleviate the aforementioned problems.

OBJECT OF THE INVENTION It is therefore an object of the present invention to provide a clamp which may overcome some or all of the above mentioned problems.

SUMMARY OF THE INVENTION In one aspect of the invention, there is provided a clamp for clamping two or more adjacent planks to form a platform for use in an elevated position, said clamp comprising; two or more spaced abutment members separated by an adjustable support member; a compression means for applying a compressive force between the abutment members; a height adjustable engagement means operatively associated with one or more of the abutment means to secure said planks against upward displacement relative to said clamp.

Preferably, said abutment members comprise clamping jaws, plates or braces, or a combination thereof.

15 Preferably, said compression means comprises one or more ***compression members operatively associated with at least one of said :abutment members.

Suitably the compression member(s) comprise a threaded shaft and nut operatively associated with an aperture of one of said abutment members such that rotation of the nut on said shaft adjusts a position of said shaft relative to said aperture.

The support member preferably comprises two or more telescopic members.

the height adjustment means is slidable relative to the abutment members.

The engagement means suitable comprises an inwardly extending lip.

Suitably the height of the engagement means is adjusted by an adjustment means which comprises a threaded shaft and nut operatively associated with an aperture of one of said abutment members such that rotation of the nut on said shaft adjusts a position of said shaft relative to said aperture.

The clamp may further comprise one or more ancillary clamp members for releasably engaging the clamp with a supporting framework.

Preferably the ancillary clamp member is connected to one or more of said abutment members.

Suitably the ancillary clamp member clamps ina direction substantially normal to the longitudinal axis of the support member and, in use substantially parallel to the plane of the platform.

The clamp may further comprise a locating means for location of the clamp to a frame member of the supporting framework.

The locating means suitably is connected to one of more of said abutment members.

In an alternative form one of said spaced abutment members, thesupport member and the engagement means are comprised of a strap having two end portions thereof connecting another of said abutmentmembers. In addition the another of said abutment members may comprise two compression members connected to ~respective end portions of said strap.. Furthermore the another said abutment members may suitably comprise a collar.

o :In the alternative form the compression members may comprise a threaded shaft and nut operatively associated with an °aperture of the collar such that rotation of the nut on said shaft adjusts a position of said shaft relative to said aperture.

25 BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention may be readily understood and put into practical effect, preferred embodiments will now be described with reference to the accompanying drawings in which: FIG. 1 is a side plan view and part cross sectional view of one embodiment of the clamp in accordance with the present invention; FIG. 2 is a top plan view of the clamp of FIG. 1; 6 FIG. 3A is a side plan view of an alternative embodiment of the clamp according to the invention showing clamping of adjacent aluminium planks; FIG. 3B is a side plan view of the clamp of FIG. 1 showing clamping of adjacent timber planks; FIG. 4 is a perspective view of the clamp of FIG. 3A showing an ancillary clamp member thereof clamping a rung of a supporting framework of a trestle;- FIG. 5 is a perspective view of the clamp of FIG. 3A showing an ancillary clamp member thereof clamping a stile of a supporting framework of a trestle and also showing a locating means of the clamp abutting to a face of the stile; FIG. 6 is a perspective view of the clamp of FIG. 3A clamping a supporting framework of a trestle and clamping two aluminium 15 planks; FIG. 7 is a side plan view of a further embodiment of the clamp in accordance with the present invention; and FIG. 8 is a cross sectional view a still further embodiment of the clamp according to the invention.

FIG. 9 is a side plan view of yet another embodiment of the *oe clamp according to the invention.

o..0 DETAILED DESCRIPTION ~Referring now to the drawings and more particular to FIGS.

1 and 2, there is illustrated an embodiment of the clamp in accordance 25 with the present invention. The clamp shown generally at 10 can be used to clamp two adjacent planks to define a platform. The clamp comprises two opposed jaw members 11, 12 and a telescopic support member 13 connected therebetween.

Each of the jaw members 11, 12 comprises a substantially rectangular hollow housing 14 having an inner face 15, an outer face 16, two side faces 17, 18, a base 19 and an open end Adjacent the open end 20 towards the inner face 15, there is provided an inwardly extending lip 21 operatively associated with the support member 13 such that, in use, upright displacement of one of the two adjacent planks.relative to the clamp 10 is substantially prevented. In this embodiment, the position of lip 21 relative to the support member 13 is adapted to capture a side wall of an aluminium plank.

In use, support member 13 supports the planks such that relative displacement therebetween is substantially prevented in an upright direction. Support member 13 comprises substantially rectangular hollow members 22, 23 which are in telescopic relationship with each other. Member 22 is connected to jaw member 11 and member 23 is connected to jaw member 12.

At a distal portion 24 of an internal surface 25 of hollow member 22, there is connected a shaft 26 which extends in a direction parallel to the longitudinal axis of hollow member 22 through a co-axially aligned sleeve 27 connected to the outer face 16 of jaw member 12. The shaft 26 comprises a threaded end portion 26A which is operatively associated with nut 28 having an internal thread complementary to the threaded end portion 26A. The relative position of jaw members 11, 12 is adjusted by rotation of the nut 28 on threaded end portion 26A against sleeve 27 to effect clamping or unclamping of the adjacent planks.

.Slidably mounted at the open end 20 of housing 14 of each Sjaw member 11, 12, are height adjustable lips 29, 30. These height adjustable lips 29, 30 are preferably used to secure timber planks of different thickness. Each of these lips 29, 30 is connected to a shaft 31 which extends substantially parallel to the longitudina axis of the housing 14 through co-axially aligned aperture 32 of base 19 of housing 14. The shaft 31 comprises a threaded end portion 33 which is operatively associated with nut 34 having an internal thread complementary to the threaded end portion 33. In operation, the respective positions of lips 29, relative to the -support member 13 are adjustable in an upright direction by rotation of nut 34 on threaded end portion 33 against outer surface of base 19.

The clamp 10 further comprises a G-clamp 35 connected to outer face 16 at a location adjacent base 19 of jaw member 11. This Gclamp 35 is disposed at an angle such that it clamps, normal to the longitudinal axis of the support member 13 and normal to the longitudinal axis of housing 14. In use, G-clamp 35 effects clamping of the clamp to a stile of a supporting framework of a trestle.

At the outer face 16 adjacent the open end 20 of jaw member 11, there is connected a plate 36 for location of the clamp 10 to a stile of the supporting framework.

The clamp 10 further comprises G-clamp 37 which is connected to outer face 16 at a location between sleeve 27 and open end of jaw member 12. In comparison to G-clamp 35, G-clamp 37 is also disposed at an angle such that it clamps normal to the longitudinal axis of the support member 13 and normal to the longitudinal axis of housing 14.

However, in use, G-clamp 37 effects clamping of the clamp 10 to a rung of the supporting framework.

Turning now to FIG. 3A, there is shown the clamp of FIG. 1, without height adjustable lips 29, 30, clamping two adjacent aluminium planks 38, 39 to define a platform 40. As shown, a side portion 41 of each of the adjacent planks 38, 39 is captured by lip 21 in operation with elongate member 13. -In use, this inhibits upward displacement of the side portion 41 of each of the adjacent planks 38, 39 when a workman 25 traverses or stands on the platform With reference to FIG. 3B, there is shown the clamp of FIG.

1 clamping two adjacent timber planks 42, 43. Generally, the thickness of timber planks may vary, and thus, respective positions of the height adjustable lips 29, 30 relative to the support member 13, in use, are adjustable in an upright direction to effect clamping of a side portion 44 of each of the adjacent timber planks 42, 43.

9 Referring now to FIG. 4, there is shown a perspective view of the clamp of FIG. 3A clamping a rung 44 of a supporting framework As shown, G-clamp 37 is used to clamp the rung 44 which substantially inhibits upward displacement of the clamp 10 relative to the supporting framework In regard to FIG. 5, there is shown a perspective view of the clamp of FIG. 3A clamping a stile 46 of the supporting framework through G-clamp 35 to substantially inhibit lateral displacement of the clamp 10 relative to the supporting framework 45. Also shown is plate 36 which acts to locate clamp 10 to an outer face 46A of the stile 46.

With reference to FIG. 6, there is shown a perspective view of the clamp of FIG. 3A clamping supporting framework 45 of trestle 47 and clamping aluminium planks 38, 39 to define a platform 48. The clamp substantially prevents relative displacement of planks 38, 39 in a lateral and an upright direction and substantially prevents displacement of the planks 38, 39 relative to the clamp 10 and relative to the supporting framework 45 of the trestle 47. This substantially improves the safety of the platform 48 for a workman 49 to stand or walk thereon.

Turning now to FIG. 7, there is shown a side plan view of another embodiment of the clamp in accordance with the, present S: invention. The clamp 100 can be used to clamp two adjacent aluminium planks 101, 102 to define a platform 103. The clamp 100 comprises two opposed jaw members 104, 105, an intermediate jaw member 106 and a shaft 107.

25 Jaw members 104, 105, 106 comprise respectively plate members 108, 109, 110 which are connected at distal portions thereof to respective sleeve members 111, 112, 113.

These sleeve members 111, 112, 113 are slidably mountable on the shaft 107 and are disposed such that the respective longitudinal axes thereof are normal to the plane of corresponding plate members 108, 109, 110. Each of sleeve members 111, 112, 113 has one or more.upper surfaces 114 which, in use, receive and support a side portion 115 of one of the aluminium planks 101,102 such that relative displacement thereof is substantially prevented in an upright direction.

Adjacent the ends of plate members 108, 109 are respective inwardly extending lips 116, 117. Adjacent one end of plate member 110 are two outwardly extending lips 118, 119. Lips 116-119 are operatively associated with the upper surface(s) 114 of sleeve members 111, 112, 113 such that each lip 116-119 captures side portion 115 of one of the aluminium planks 101, 102. In use, these lips 116-119 substantially prevent upright displacement of two adjacent planks relative to the clamp 100.

The shaft 107 extends through sleeve members 111, 112, 113 and protrudes outwardly from jaw members 104, 105 through respective apertures 108A and 109A atdistal portions of plate members 15 108 and 109 as shown. The shaft 107 comprises two threaded end portions 120, 121 which are operatively associated with nuts, 122, 123 respectively. The relative position of jaw members 104, 105, 106 is adjusted by rotation of the nuts 122, 123 on respective threaded end :portions 120, 121 against respective outer surfaces of plates 108, 109 to effect clamping or unclamping of the aluminium planks 101,102.

Referring now to FIG. 8, there is.shown a cross sectional view of yet another embodiment of the clamp in accordance with the present invention. The clamp 200 is adapted to clamp two timber planks o*oo 2 201, 202 to define a platform 203 having an upper surface 204 and a bottom surface 205.

The clamp 200 comprises a strap 206 having two end portions 207, 208 connected to shafts 214, 215 which are are slidably mounted in channels 212, 213 of collar 209 located at boundary 210 of platform 203. The strap 206 extends along the upper surface 204 from boundary 210 to an opposite boundary. 211 of the platform 203 and returns along the bottom surface 205 to boundary 210.

1*1 The longitudinal axes of mounting shafts 214, 215 are substantially parallel to the plane of the platform 203 in use. The shafts 214, 215 are operably connected at respective end portions 216, 217 thereof to end portions 207, 208 of the strap 206. The shafts 214, 215 further comprise threaded- end portions 218, 219 respectively extending through apertures 220, 221 of the collar.209. These threaded end portions 218, 219 are operatively associated with nuts 222, 223 wherein rotation of the nuts 222, 223 on respective threaded end portions 218, 219 against outer surface 209A of collar 209 adjusts respective positions of shafts 214, 215 relative to outer surface 209A to effect clamping or unclamping of the two planks 201, 202.

In an alternative embodiment shown in FIG. 9, the clamp 300.comprises a pair of opposed brace members 301, 302 in telescopic relationship with hollow elongate members 303, 304, 305 therebetween.

Elongate members 303, 305 are connected respectively to brace members 301, 302 and elongate member 304 is slidably engagable with each of the other elongate members 303, 305. Extending parallel to the Soo.

i longitudinal axis of elongate member 304 is support rib 304A as shown which receives and supports a plurality of planks in- use.

Brace -members 301, 302 each comprise inwardly extending lips 314, 315 which are operatively associated with rib 304A such that 0oo.

side portions of adjacent aluminium planks are engaged in use.

Slidably mounted in apertures 306, 307 of brace members 301, 302 is threaded shaft 308. One end 309 thereof is connected to :see. 25 plate 310 which, in use, abuts to outer face 302A of brace member 302.

Shaft 308 extends from plate 310 through apertures 307 in a direction parallel to the longitudinal axis of elongate members 303, 304, 305 and protrudes outwardly from apertures 306 of brace member 301. An end portion 311 of shaft 308 is operatively associated with washer 312A and nut 312 which is connected to handle 313'as shown such that the relative position of brace members 301, 302 is adjustable by. rotation of handle 313.

In contrast to plate members being used as abutment members, as for example illustrated in FIG. 7, brace members 301, 302 provide increased strength against lateral deflection of the planks in use.

Moreover, clamp components including brace members 301, 302, elongate members 303, 305, nut 312 and handle 313 are suitable for assembly of various sized clamps for clamping different numbers of planks. Accordingly, these generic components may be mass produced while manufacturing different lengths of elongate member 304 and shaft 308 commensurate with the number of planks desired to. be clamped.. This embodiment may therefore provide for substantial commercial advantage.

Theprimary advantage of the clamp of the subject invention is that relative displacement of adjacent planks is substantially prevented 15 in a lateral and upright direction. In a preferred embodiment, the clamp of the invention substantially prevents upright displacement of the planks relative to the clamp. Furthermore, in another preferred embodiment, the clamp substantially prevents lateral and upright displacement of adjacent planks relative to a supporting framework. Thus, the clamp of the present invention may be used to secure adjacent planks on a supporting framework to provide a safer elevated platform.

*o o: o:io°

Claims (19)

1. A clamp for clamping two or more adjacent planks to form a platform for use in an elevated position, said clamp comprising: two or more spaced abutment members separated by an adjustable support member; a compression means for applying a compressive force between the abutment members; a height adjustable engagement means operatively associated with one or more of the abutment means to secure said planks against upward, displacement relative to said clamp.

2. A clamp as. claimed in Claim 1 wherein said abutment members comprise clamping jaws, plates or braces, or a combination thereof.

3. A clamp as claimed in Claim 1 wherein said compression means comprises one or more compression members operatively associated with at least one of said abutment members.

4. A clamp as claimed in Claim 3 wherein said compression member(s) comprise a threaded shaft and nut operatively associated with 20 an aperture of one of said abutment members such that rotation of the nut on said shaft adjusts a position of said shaft relative to said aperture.

5. A clamp as claimed in any one of Claims 1-4 wherein said support member comprises two or more telescopic members.

6. A clamp as claimed in any one of Claims 1-5 wherein the height adjustable engagement means is slidable relative to the abutment members. C C C *CCC

7. A clamp as claimed in Claim 1 wherein the engagement means comprises an inwardly extending lip.

8. A clamp as claimed in Claim 7 wherein the height of the engagement means is adjusted by an adjustment means which comprises a threaded shaft and nut operatively associated with an aperture of one of )ir 14 said abutment members such that rotation of the nut on said shaft adjusts a position of said shaft relative to said aperture.

9. A clamp as claimed in any one of Claims 1-8 further comprising one or more ancillary clamp members for releasably engaging the clamp with a supporting framework.

A clamp as claimed in Claim 9 wherein the ancillary clamp member is connected to one or more of said abutment members.

11. A clamp as claimed in Claim 9 wherein the ancillary clamp member clamps in a direction substantially normal to the longitudinal axis of the support member and, in use, substantially parallel to the plane of the platform.

12. A clamp as claimed in any one of Claims 1 further comprising a locating means for location of the clamp to a frame member of the supporting framework.

13. A clamp as claimed in Claim 12 wherein the locating means is S 15 connected to one or more of said abutment members. o

14. A clamp as claimed in Claim I wherein one of said spaced abutment members, the support member and the engagement means are comprised of a strap having two end portions thereof connecting another of said abutment members. oi 20

15. A clamp as claimed in Claim 14 wherein the another of said abutment members comprises two compression members connected to respective end portions of said strap.

16. A clamp as claimed in Claim 15 wherein the another of said abutment members comprises a collar.

17. A clamp as claimed in Claim 16 wherein each of said compression members comprises a threaded shaft and nut operatively associated with an aperture of the collar such that rotation of the nut on said shaft adjusts a position of said shaft relative to said aperture.

18. A clamp for securing two or more adjacent planks disposed on a supporting framework, said clamp comprising the features of any one of the preceding claims and as herein described with reference to the accompanying drawings.

19. A method of securing two or more adjacent planks disposed on a supporting framework, said method comprising the step of clamping said planks with a clamp according to any one of the preceding claims. Dated this nineteenth day of July 2000 TOMMY TUCKER TRESTLES PTY LTD By their Patent Attorneys FISHER ADAMS KELLY 0 0