WO2003048483A1

WO2003048483A1 - A scraper for cleaning concrete

Info

Publication number: WO2003048483A1
Application number: PCT/SE2002/002237
Authority: WO
Inventors: Uno Strandberg
Original assignee: Renov I Bjurholm Ab
Priority date: 2001-12-07
Filing date: 2002-12-05
Publication date: 2003-06-12
Also published as: SE0104119L; SE520892C2; SE0104119D0; AU2002358368A1

Abstract

The present invention relates to a scraper (1) and in particular to a scraper for use with boards used in the construction of pourable concrete structures. The scraper (1) has a handle (2), a guide and scraping studs (5) which are both movable by the handle (2). The guide is formed for locating the scraper (1) on an edge of a board and guiding the scraper (1) along the edge of the board. The scraping studs (5) are formed for engagement with the edge of the board for removing residual material adhered thereto.

Description

A scraper for cleaning concrete

The present invention relates to a scraper and in particular to a scraper for use with boards used in the construction of pourable concrete structures.

It is well known in the construction industry to build concrete structures by first erecting a frame made from wooden boards defining the dimensions of the desired concrete structure and then pouring the concrete into the frame. The concrete is allowed to set and the frame is dismantled from the hardened concrete structure. The boards are suitable for repeated use and in order to ensure uniformity of dimension and quality of the edges of the manufactured concrete structures, the boards must be thoroughly scraped in order to ensure that no residual material remains on or about the boards and in particular on or about the edges of the board.

Traditionally, an operator utilises any available tool having a substantially flat sharp portion for scraping along the edge of the board after the board has been used as part of a frame. This process is time consuming, as an operator must continuously relocate the scraping tool back in contact with the portion of the board desired to be cleaned. Additionally, injuries to an operator cleaning a board in this way are common as the tool for scraping the board often unexpectedly slips off the edge of the board and the operator's hand scrapes along the edge of the board instead of the tool.

Clearly there is a need for an improved method of cleaning boards of this type in order to reduce the time required to clean such boards and to reduce the risk of injury to an operator who is responsible for the scraping operation.

Accordingly, the present invention provides a scraper for use with boards used to construct concrete structures such as walls comprising a handle, a guide means and a scraping means which are both movable by the handle, the guide means being formed for locating the scraper on an edge of a board and guiding the scraper along the edge of the board and the scraping means being formed for engagement with the edge of the board for removing residual material adhered thereto.

This apparatus reduces the time required to completely clean an edge of a board and also prevents the risk of injury to an operator's hand as the guide means prevents the scraper from slipping off the edge of the board. The guide means and the scraping means are both connected, directly or indirectly, to the handle.

Ideally, the scraping means is located within the guide means.

Preferably, the guide means defines apertures around the scraping means. Residual material which has been scraped off the board passes out of the scraper through these apertures. The apertures help to reduce friction between the edge of the board and the scraper otherwise caused by loose residual material trapped between the scraping means and the board.

Ideally, the handle defines a rib and groove formation for improving an operator's grip on the handle. This is particularly important as operators working on building sites and other similar environments requiring the use of this apparatus often wear heavy gloves.

Preferably, the guide means is an elongate u-shaped channel section. The edges of boards used in the construction of concrete structures generally have a square from and the guide means is formed for cooperation therewith.

Ideally, the two free longitudinal edges of the u-shaped channel section diverge from one another forming two outwardly extending lips. The lips assist with the location of the channel section onto the edge of the board.

Preferably, the u-shaped channel section comprises a base and two outwardly extending legs opening away from the handle.

Ideally, a support block is mounted between the guide means and the handle. The support block provides a mounting point for the handle and the guide means and improves the structural integrity of the scraper.

Preferably, the scraping means is mounted within the u-shaped channel section on the base thereof. The outwardly extending legs of the u-shaped channel section are parallel to the two main surfaces of the board when the scraper is in an in use position on the board and the scraping means abuts against the edge of the board between the two main surfaces. Ideally, the scraping means is provided by a number of studs equispaced along the base of the channel section. The studs are produced from a material which is hard enough to resist excessive wear due to friction between the studs and the edge of a board and wear due to impact forces between the studs and residual concrete on the edge of the board.

Preferably, the studs are fastened to the support block through the base of the channel section.

Ideally, the studs are rotatable relative to the channel section. The leading edge and trailing edge of the studs are blunted during use and rotating the studs allows the working life of the scraper to be extended.

Preferably, the scraper has a nail puller mounted on one end.

Ideally, the channel section defines additional apertures on its legs. These additional apertures allow material which has been scraped from the edge of the boards as well as from the main surfaces of the boards parallel to the legs to escape out of the scraper.

The present invention will now be described with reference to the accompanying drawings, which show by way of example only, one embodiment of a scraper in accordance with the invention. In the drawings: -

Figure 1 is a front elevation view of a scraper in accordance with the invention;

Figure 2 is an end view of the scraper of Figure 1 ;

Figure 3 is a front elevation detail view of a support block; and

Figure 4 is a plan detail view of the support block of Figure 3.

Referring to Figures 1 and 2, there is shown a scraper indicated generally by the reference numeral 1. The scraper 1 includes a handle 2, a support block 3, a guide 4 and scraping studs 5. A nail puller 6 is mounted at one end of the scraper 1 on the support block 3. The handle 2 is mounted at an angle on the support block 3 by a centrally located shaft 7 and the handle 2 defines a rib and groove formation 8 on an external portion thereof. The guide 4 is mounted on the opposite side of the support block 3 to the side which the handle 2 is mounted on and has a u-shaped profile defining a longitudinally extending u-shaped channel section 9. It will of course be appreciated that the handle 2 may extend from the block 3 perpendicular or at any desired angle to the guide 4. The free ends of both legs 10 of the u-shaped channel section 9 diverge from one another defining two outwardly extending lips 11. The guide 4 is connected to the block 3 by bolts 12 which pass through scraping studs 5 and a base 15 of the u-shaped channel section 9 into the support block 3. Apertures 16 are defined on the guide 4 around the scraping studs 5 and additional apertures 17 are defined along the guide 4. The nail puller 6 is mounted on the support block 3 by four countersunk bolts 18. The nail puller 6 has a mounting body 19 and an active component 20. The active component 20 is provided by a flat plate defining a v-shaped recess 22 opening towards a free edge of the plate away from the support block 3. The active component 20 is inclined away from the vertical when the scraper 1 rests in a horizontal position.

Referring now to Figures 3 and 4 there is shown a detail view of the support block 3. The support block 3 defines four tapped bores 31 in one surface of the support block 3 for receiving bolts 12 (see Figure 1) and an inclined tapped bore 32 in another surface for securing the handle 2 (see Figures 1 and 2) thereto. Four additional threaded bores 33 extend through the support block 3 at one end thereof substantially perpendicular to the bores 31 for receiving the countersunk bolts 18 securing the nail puller 6 to the block 3 (see Figures 1 and 2).

In use, an operator lifts the scraper 1 by the handle 2 engaging the gripping portion of the fingers with the rib and groove formation 8. The scraper 1 is moved towards an edge of a board (not shown), which is used for forming poured concrete structures, but during the scraping operation is normally separated from other boards. The lips 11 assist the operator with locating the guide 4 over the edge of the board and the operator moves the scraper 1 towards the board until the scraper studs 5 engage with the board edge. The legs 10 of the u- shaped channel section 9 are parallel with the main surfaces of the board and are in contact therewith. An operator moves his hand back and forward in a reciprocating motion parallel to the edge being scraped and the scraper studs 5 remove any residual material from the edge of the board. Released material can pass through the apertures 16 and 17 as the scraper 1 is moved along the edge of the board. An operator does not need to worry about the scraper's location as the legs 10 of the u-shaped channel section 9 guide the scraper 1 along the correct path.

In order to remove a nail from the board, an operator manipulates the scraper 1 to engage the narrow neck of the v-shaped recess 22 of the nail puller 6 under the head of a nail (not shown) and pivots the scraper about the line connecting the body portion 19 and the active component 20 of the nail puller 6. As the scraper 1 pivots a tensile force is applied to the head and body of the nail overcoming the shear forces between the board and the section of the nail buried in the board.

It will of course be appreciated that the details of the specific embodiment are given by way of example only and in no way limit the invention and that various alterations and modifications may be made to the scraper without departing from the scope of the invention as defined in the appended claims.

Claims

CLAIMS 1. A scraper (1) for use with boards used to construct concrete structures such as walls comprising a handle (2), a guide means and a scraping means which are both movable by the handle (2), the guide means being formed for locating the scraper (1) on an edge of a board and guiding the scraper (1) along the edge of the board, the scraping means being formed for engagement with the edge of the board for removing residual material adhered thereto.

2. A scraper (1 ) as claimed in claim 1 wherein the scraping means is located within the guide means.

3. A scraper (1) as claimed in claim 2 wherein the guide means defines apertures around the scraping means.

4. A scraper (1) as claimed in any preceding claim wherein the guide means is an elongate u-shaped channel section (9).

5. A scraper (1) as claimed in claim 4 wherein the u-shaped channel (9) opens away from the handle (2).

6. A scraper (1) as claimed in any of claims 4 to 5 wherein the scraping means is mounted within the u-shaped channel section (9) on a base (15) thereof.

7. A scraper (1) as claimed in any preceding claim wherein the scraping means is provided by a number of studs (5).

8. A scraper (1) as claimed in any preceding claim wherein a nail puller (6) is mounted on one end thereof.