The present invention relates to a device for planation of a fresh concrete surface by means of surface vibration and comprising a planation means, provided with a vibrator and an attachment for a holder rotatably mounted in the vertical plane.

Background of the invention

The demands for surface smoothness on e.g. concrete floor surfaces are now relatively high and there is a desire that already at the planation of the fresh concrete such a high smoothness should be provided, that no subsequent curings are needed. It is especially difficult to achieve a sufficiently level surface for large continuous surfaces, paticularly if screeding paths or other levelling means may not be used or has already been removed in order not to leave any marks on the floor surface.

Up to now manual methods have been used for the final planation, namely planation with a float or steel grinding with a steel disk. Any remaining surface irregularities have been prepared after the hardening of the concrete.

It is also known so called vibrating screeds at working of large surfaces, which at the moulding is divided into long strips and where the screed rests on edge moulds during the vibration. If the edge moulds are taken away from the fresh concrete damages will occur which must be mended in some way.

At smaller concrete moulding works so called vibrating shovel compactors are used, but this tool only compensates the hand tamping of the concrete with vibration. This tool is not adapted for finishing e.g. providing a surface planation, as the vibrator of the shovel acts to the bottom of the concrete causing a too high vibration effect. Besides the vibrator shovel is very labour demanding and because of its heaviness causes high strains on the back and arms.

The object and most important features of the invention

The object of the present invention is to provide a device which is suitable for planation of a fresh concrete surface without leaving any marks on the way to or from the place where the planation is to take place. Furthermore the device should be so constructed that it can prepare very small volumes, which are to be levelled over a larger or smaller area, as well as larger volumes. These objects have been attained by the fact that the vibrator is a pneumatic, light¬ weight ball vibrator, which with respect to the vibration effect is adjustable at the free end of the holder by means of a flow regulating valve.

-Description of the drawings

Fig. 1 shows a side view, partly in section of the device according to the invention,

Fig 2 shows the device according to fig. 1 in a view from above.

Fig. 3 shows in perspective a modified planation device according to the invention.

Description of embodiments

The planation device according to fig. 1 and 2 consists of a planation means II in the form of a trough shaped plate 11 with gently upwards bent edges 12. Inside the trough-shaped plate 11 transversely to this there are arranged two attachments 13. partly for supporting a vibrator 14 and partly as a holder for pivots 15 about which a clamp 16 is rotatable at one end of the holder 17. In order to get enough stability the plate 11 is equipped with diagonally arranged reinforcing springs 18 integrated with the bottom plate and firmly connected with the attachments 13. The plate 13 is preferably manufactured of a light material such as aluminium or glass fibre reinforced plastic.

It is very important in this connection that the device has such a low weight as possible and for this reason a pneumatically driven ball vibrator has been chosen as vibrator, the special feature of which is that its vibration effect can be adjusted from 0 to maximum and that it has a low weight. The compressed air hose is placed in the holder 17 and is connected to the vibrator 14 by a pressure regulator 20.

In the holder 17 which is rotatable in the vertical plane and which can have a length of several meters, for example 4 meters, consists of a light metal pipe and is at its end facing away from the plate equipped with a quick coupling 21 for connection to a compressed-air compressor and with a flow regulating valve 22 for adjusting the vibration effect by mens of a handle 23.

As the vibration effect can be adjusted from the free end of the holder 17 and the holder can be given a considerable length it is possible to prepare very large continuous concrete surfaces without entering upon the fresh concrete. It is also possible to move the device to a place where a surface process is to take place, and without the planation device leaving any marks. For obtaining a good vibration effect it is necessary that the vibration waves extend over the whole plate substantially regularly, which is a difficulty when there are thin plates which should have a low weight, and which is provided by equipping the plate with said reinforcing springs 18.

The embodiment according to fig. 3 differs from the first described embodiment by the fact that the planation means 11 consists of a single-curved, plate having a part-circular cross-section, where the vibrator 14 is arranged on the inside of the pipe like means 11. while the attachment 13 for the holder 17 is placed opposite the vibrator on the outside of the "pipe" .

The design of the planation means admits adjustment and/or displacement of relatively large amounts of concrete. with

substantially the same favourable effect as the trough-like plate.

The invention is not limited to the showm embodiments but a plurality of variants are possible within the scope of the claims.

OMPI