WO2011008080A1

WO2011008080A1 - Device for moving reinforcing mats

Info

Publication number: WO2011008080A1
Application number: PCT/NL2010/000104
Authority: WO
Inventors: Christianus Wilhelmus Getrudus Maria Geurts
Original assignee: Vlechtersbedrijf Geurts
Priority date: 2009-07-13
Filing date: 2010-07-07
Publication date: 2011-01-20
Also published as: NL1037116C2

Abstract

A device for moving reinforcing mats is fitted with elements (1) for picking up a stack of reinforcing mats (3) and for selectively releasing a reinforcing mat. The elements (1) when in operation are inserted through the mesh in a reinforcing mat. The elements (1) contain a first (10) and a second part (11) with a gear (13a, 13b). Between the parts a slit extends (12). Gear teeth situated opposite each other form an area of support for a wire of a mat. The device also contains a drive for rotating the gears in opposite directions.

Description

Device for moving reinforcing mats.

The invention relates to a device for moving reinforcing mats provided with elements for picking up a stack of reinforcing mats and the selective release of a reinforcing mat, which elements when in operation are inserted through the mesh in a reinforcing mat.

Reinforcing mats are used in the building industry. Reinforcing mats need to be transported to the building site and be delivered to the correct location there. The

transportation of reinforcing sheets is usually carried out by truck or by other means of transport whereby the reinforcing sheets are transported by the stack. At the building site the reinforcing sheets are then transported to the location at which they will be used. This is often done by hand. The weight of the reinforcing sheets is such that a large number of people, approximately eight, is needed for moving a reinforcing sheet. For reasons of economy this number is not always adhered to. The weight and the dimensions of the mats are such that this can lead to dangerous situations.

There are various devices known for moving reinforcing mats in order to prevent this.

The Dutch patent specification NL 1027861 shows a device containing a frame which can be fitted around a stack of mats, whereby the stack is retained by a number of means of support and separation pins on the perimeter of the stack of mats. A lowermost mat in a stack is supported in operation by the means of support. The separation pins are inserted between the lowermost mat and a mat above. The means of support can hinge to a release position in order to release the lowermost mat. This makes it possible for a stack of mats to be transported and for a lowermost mat to be released. The stack of mats is supported at its perimeter. The disadvantage of this is that the device in accordance with this design is very bulky and heavy. The mats can also sag as they are supported only at their perimeter.

The Japanese patent application JP 01-317919 shows a device equipped with four fork-like elements, each containing two prongs, at the corners of a carrying frame. The fork- like elements are inserted through a stack of mats, whereby wires of the mat lie between the prongs of the forks. There are hooks on one side of a prong. The hooks can be set in two positions by means of levers. In one position a hook supports a mat, in the other position it does not The vertical distance between the hooks is approximately equal to the vertical distance between the mats in a stack of mats. By moving the levers to and fro the lowermost mat can be released, while the rest of the stack remains supported by the other hook. This construction entails a complicated procedure. The Japanese patent application JP 5330779 shows a device equipped with four elements on the vertices of a frame which are inserted through the mesh of a mat. Each element contains a chain equipped with hooks. The chain rotates over the uppermost and lowermost gears. The hooks support mats in a stack. By allowing the chain to rotate, a stack can be picked up and then transported. The lowermost mat can be released by rotating the chain a short way.

While the above-mentioned Japanese patent specifications show devices which make it possible for mats to be released one by one, the devices are heavy and complicated. One of the invention's aims is to provide a device of the type mentioned in the first paragraph which reduces one or more of the drawbacks mentioned.

For this purpose the device according to the invention is characterised by the fact that the elements which in operation are inserted through the mesh of the mats, contain a first and a second part with a gear, between which parts a slit extends, whereby gear teeth opposite each other form an area of support for a mat, and the device contains a drive for rotating the gears in opposite directions.

The invention has a number of advantages:

The construction is relatively light.

It is possible for any number of mats to be picked up and released quickly and accurately by moving the gears.

The mats can not come loose unintentionally, or it would be difficult for them to do so, even when violent movements are made.

It has been found that even with two elements stacks of mats can be transported quickly and safely. This forms a preferred embodiment as it simplifies the device. In the known prior arts the device comprises four elements on the vertices of a frame. the friction between the elements and the stack of mats on picking up and releasing is slight

the design offers a great deal of flexibility. Measured over the circumference of a gear, the distance between the teeth of a gear is preferably between 11 and 19 mm.

The thickness of the steel wire from which reinforcing mats are made can vary and is typically 8 to 12 mm, with intervals of 1 mm. For mats as described above the device can be used for at least two and often three types of reinforcing mats.

The device preferably contains a spring construction for varying the distance between the gears. Under some circumstances a mat can become trapped between the gears. By adding a

(preferably relatively rigid) spring construction which, under such circumstances offers the possibility of making the slit bigger, this problem is solved or in any case, diminished.

These and further aspects of the invention are described below and illustrated by the drawing:

In the drawing:

Figure IA shows a device according to prior art

Figure 1 B shows a detail of a device according to prior art

Figure 2 A shows a device according to prior art

Figure 2B shows a detail of a device according to prior art

Figure 3 shows a device according to the invention

Figure 4 shows a detail of the embodiment of a device according to the invention.

Figure 5 shows an illustration of the invention

Figure 6 shows a detail of an embodiment according to the invention

Figure 7 shows a detail of a preferred embodiment of a device according to the invention Figure 8 shows a gear for the preferred embodiment of a device according to the invention.

Figure 9 shows a detail of a preferred embodiment of a device according to the invention

Figure 10 shows the spring of a section

Figure 11 shows a side-view of a device

Figures 12 and 13 show other preferred embodiments of a device according to the invention. The figures are exemplary figures; the same parts are generally indicated by the same reference numbers.

Figures IA and IB show a device known from the Japanese patent specification JP 131791. On the vertices of frame 2 elements 1 are provided which are inserted through the mesh of a stack of reinforcing mats 3. The elements 1 are equipped with levers 4. The elements 1 contain two prongs. The fork-like elements 1 are inserted through a stack of mats, whereby wires of the mat lie between the prongs of the forks. On one side of a prong hooks 5, 6 are provided, see figure IB. The hooks can be set in two positions by means of levers 4. In one of the positions a hook supports a mat, in the other position it does not. The vertical distance between the hooks 5, 6 is approximately equal to the vertical distance between the mats in a stack of mats. Due to this a lowermost mat in a stack can be released. The construction is heavy and complicated; it is very difficult to release the two or three lowermost mats quickly.

Figures 2A and 2B show a device known from the Japanese patent specification JP 5330779. The device is equipped with four elements 1 on the vertices of a frame 2 which are inserted through the mesh of a mat. Each element contains a chain equipped with hooks 8. The chain rotates over an uppermost and lowermost gear. The hooks support mats 9 in a stack. By allowing the chain to rotate, a stack can be picked up and then transported. A lowermost mat can be released by the rotating the chain a short way. However, the construction is heavy and can easily become trapped between the mats. Therefore a device is needed that works more efficiently and more simply and which is lighter.

Figures 3, 4, 5 and subsequent show and illustrate embodiments and details of a device according to the invention.

The device contains elements 1 which are inserted through the mesh of a stack of mats 3. The elements contain a first and a second part 10 and 11, between which parts a slit extends, see figure 3. At the far ends of parts 11 and 12 gears 13a and 13b are provided. The device is equipped with a drive for making the gears rotate in opposite directions, hi a preferred embodiment at least one of the parts is equipped with a spring construction 14.

Figure 5 illustrates the invention. The two gears 13a and 13b rotate in opposite directions. Due to the rotation, one mat 15 is released at a time. By allowing the gears to run through a stack of mats, any number of mats can be picked up. This requires no effort or force as penetrating through the mats the gears are able to move through the stack of mats freely without the device exercising force on the mats or vice versa. Once the number of mats to be lifted has been reached, the position of the gears is locked in place and the stack is lifted and can be moved. At the place where the mats need to be released any number of mats can easily be released in a controlled and simple manner.

The device is simple and offers a great deal of flexibility. The friction between the device and the mats during the process of picking up the mats, lifting them and releasing them is minimal.

Figure 6 shows a detail of a preferred embodiment of a device according to the invention. In this preferred embodiment the invention is equipped with a tooth position meter 16. The tooth position meter 16 measures the position of a tooth in a gear. In embodiments this is done by means of an optical sensor, though electrical sensors can also be used. The tooth position meter gives a signal I which regulates the drive. If the tooth position meter indicates that a tooth has been brought into the correct position for holding on to a stack, then the position of the teeth is locked. This makes it possible for a number of mats to be released in a controlled and accurate way. Figure 6 also illustrates another preferred embodiment of the invention. Parts 10 and 11 and the gears are equipped with means of alignment U in order to orientate the gears in the same way and in a unique way each time are changed. Figure 7 shows a detail of a preferred embodiment of a device according to the invention. One of the parts, in this case part 10, is split into two parts, a lower and an upper part, between which there is a slit 17. A spring construction 14 is fitted over the slit 17. Under some circumstances a mat can become trapped between the gears. The spring construction 14 prevents the gears from coming out of alignment and/or the device becoming trapped. When using two elements preferably both the inside or both the outside parts of the elements are equipped with spring constructions.

In embodiments the connection between the drive and the gears can be formed by a fixed connection, but preferably, and in particular if one of the parts is equipped with a spring construction, the connection between the drive and the gears is formed by a chain or belt. This provides some flexibility in the drive and prevents the drive of the gears breaking down in the case of one of the parts starting to bounce. Figure 8 illustrates a gear for preferred embodiment of a device according to the invention. The thickness dl of the wires from which a reinforcing mat is made is 8, 9, 10, 11 or 12 mm. Preferably the distance d for gears, whereby the distance is defined as the repeating distance, meaning the distance between the fronts of consecutive teeth, or the backs of consecutive teeth, is 11 to 19 mm. For such distance the device can be used for at least two types of reinforcing mats without any adjustment being required. The distance d between the teeth if preferably 1.5 times the thickness of the reinforcing wire plus or minus 1 mm, so for a thickness of 8 mm: 12 mm (± 1 mm), for 9 mm: 13.5 mm (± 1 mm), for 10 mm: 15 mm (± 1 mm), for 11 mm: 16.5 mm (± 1 mm), for 12 mm: 18 mm (± 1 mm). A gear for a wire thickness of x mm can however also be used straight away for a wire of x-1 or x+1 mm. Furthermore, it is true that the variation which is allowed in the teeth distances makes it possible for gears of the same diameter to be used for all wire thicknesses. This provides the design with a great deal of simplicity and a great deal of flexibility which is not found in existing designs. Firstly, the device can be used without any adjustment for the various wire thicknesses if there is only a minor difference in the wire thickness of consecutive mats. If one has first picked up a mat with a wire thickness of 10 mm and then wants to pick up a mat with a wire thickness of 11 or 9 mm then no changes need to be made. Secondly, if a gear needs to be replaced already because, for example, one if changing from 8 mm mats to mats with a wire thickness of 12 mm, then changing the gears suffices. As the diameter of the gears for various wire thicknesses remains practically the same neither the distance between parts 10 and 11 nor the drive need to be changed. This again simplifies the use of the means of alignment as the same means of alignment can be used for all sizes of gears. As an example: If one keeps to teeth spacing d of 15 mm for a gear that is pre-eminently suited to a wire thickness of 10 mm, then this gives the gear a circumference of 225 mm (=15x15 mm) if the gear comprises 15 teeth. The same circumference of 225 mm for the gear can be obtained with

19 teeth with teeth spacing of 11.8 mm (pre-eminently suited to 8 mm wire thickness)

17 teeth with teeth spacing d of 13.2 mm (pre-eminently suited to 9 mm wire thickness)

14 teeth with teeth spacing d of 16.1 mm (pre-eminently suited to 11 mm wire thickness)

12 teeth with teeth spacing d of 18.75 mm (suited to 12 mm). The whole spectrum of common wire thicknesses 8, 9, 10, 11 and 12 mm can be covered with three (for 8, 10 and 12 mm) or even just two (for 9 and 11 mm) sets of gears, all having the same diameter of 225 mm.

Such simplicity of and flexibility in use can not be offered by any of the known devices.

Preferably the gears contain notches between the teeth 18 formed by sections 19, situated next to the teeth, with a radius of curvature smaller than the distance between the teeth, separated by a section 20, with an radius of curvature larger than the distance between the teeth. This provides good support for the mats without a lot of friction.

Figure 9 gives further details of a device according to the invention. A drive 21 drives chains 22. Via gears 23 and 24 these chains drive shafts 26 onto which the gears are attached.

Figure 10 again illustrates parts 11 and 10. Part 10 is equipped with a slit 17 and a crossover point 26. A spring construction, shown in detail in figure 4, is fitted over the slit. This provides the lowermost part of part 10 with flexibility. This part can tilt around the crossover point 26. Schematically this is shown in figure 10 by the double arrow. This prevents the device from becoming jammed. Figure 11 gives a perspective side-view of a preferred embodiment of a device according to the invention. On both sides of the device a part with gears and parts 11 and 10 are provided. In order to simplify the drawing this part is shown only at the front of the device. The part with the gears can be moved up and down. The device is equipped with a number of compartments between which hinge points are found. In two of the compartments, in this preferred embodiment, batteries 27 are fitted for supplying power to the drive.

The drives can be fitted with means of synchronisation for making the drives run synchronically.

The first hinge point 28 is situated, seen along the length of the device, at around the halfway point.

Figure 12 shows the advantage of this hinge point. The hinge point makes it possible to fold the device double. This halves the length of the device which would normally be around 3 metres. The benefit of this is that the device is easy to transport. The existing devices are very heavy and large and need to be transported by truck. As a hinge point has been provided at the halfway point, making the device foldable and making it possible for it to be halved in length, the preferred embodiment shown in figures 11 and 12 can be transported in a van.

Furthermore hinge points 29 are provided in the preferred embodiments, seen along the length of the device, at approximately a quarter and three quarters of the way along the length.

Figure 13 shows the advantage of these hinge points 29. These make it possible to make a construction as shown in the right-hand part of figure 13. In this presentation it is possible to pick up a mat by the edge of the mat and lift it. If one does this, then the mat will be pulled up at an angle. The mat will hang practically vertically. It is sometimes necessary to affix mats to side walls or under a corner. Using the existing devices this is impossible. Using the presentation shown in figure 13 this is a possibility.

Figure 11 shows another detail. The underside of the device is provided with extending stabilisers 30. The underside is the side where the opening of slits 12 is found.

In operation the stabilisers 30 are extended downwards and press down with spring resilience or simply through their own weight, but preferably with spring resilience, on the mats picked up by the device. This stabilises the position of the mats and keeps the mats in a horizontal position. It has been found that the necessary spring resilience is only slight, in the range of 10-30 kgf, in order to stabilise the position of the mats. In simple presentations the stabilisers are fitted with springs in order to press these onto the mats. In other presentations this can be done by pneumatic pressure if more force is required.

It will be clear that within the scope of the invention many variations are possible and that the invention is not limited to the examples given above.

For example, the device can be fitted with hooks on the top for hoisting the device. The device can also be placed in, be a part of or suspended from a mobile gantry which can be driven over a stack of mats, then allows parts 10 and 11 to be lowered, picks up and moves the stack of mats. The mobile gantry can be fitted with caterpillar tracks for moving the stack of mats across a site.

Claims

Claims:

1. Device for moving reinforcing mats fitted with elements (1) for picking up a stack of reinforcing mats (3) and selectively releasing one reinforcing mat, which elements when in operation are inserted through the mesh in a reinforcing mat, characterized in that the elements (1) contain a first (10) and a second part (11) with a gear (13a, 13b), between which parts a slit (12) extends, whereby gear teeth positioned opposite each other form a support area for a mat, and the device contains a drive for rotating the gears in opposite directions.

2. Device according to claim 1 , characterized in that the distance (d) between the teeth of a gear, measured around the circumference of a gear is between 11 and 19 mm.

3. Device according to one of the preceding claims, characterized in that the gears display notches between the teeth (18) formed by sections (19), situated next to the teeth (18) with a radius of curvature smaller than the distance between the teeth, separated by a section (20) with a radius of curvature larger than the distance between the teem.

4. Device according to claim 1 or 2, characterized in that the device contains a spring construction (14) for varying the distance between the gears (13a, 13b).

5. Device according to claim 1, 2 or 3, characterized in that the device contains a tooth position meter (16).

6. Device according to one of the preceding claims, characterized in that the device contains only two elements.

7. Device according to claim 4, characterized in that the device, at least for a part that contains a spring construction, contains a chain (22) or belt for driving the gear (13).

8. Device according to one of the preceding claims, characterized in that the parts ( 10, 11 ) and the gears ( 13a, 13b) are equipped with means of alignment (U).

9. Device according to one of the preceding claims, characterized in that the device is equipped with a hinge (28) for enabling the device to be folded double.

10. Device according to one of the preceding claims fitted with hinges (29) for hinging the compartments with parts 10, 11.

11. Device according to one of the preceding claims, characterized in that the device is fitted with stabilisers (30) on the underside for stabilising the position of a stack of mats which has been picked up.