US20170073983A1

US20170073983A1 - Device for smoothing

Info

Publication number: US20170073983A1
Application number: US15/124,023
Authority: US
Inventors: Frank Freudenreich; Dirk Neddermann
Original assignee: Nela GmbH
Current assignee: Nela GmbH
Priority date: 2014-03-06
Filing date: 2015-02-27
Publication date: 2017-03-16
Also published as: WO2015131868A1; DE102014002951A1; EP3114290A1

Abstract

A device (1) for smoothing filling or plaster compounds and/or for spreading them by rubbing, comprising a smoothing plate (2) with a smoothing side (3) and a fastening side (4), a handle (5) and a holding element (6) which connects the handle (5) and the smoothing plate (2) on the fastening side (4), wherein the holding element (6) has a fastening flange (7) for fastening the smoothing plate (2), and a handle-fastening section (8), is intended to be improved in such a way that the handle is connected to the smoothing plate in a particularly stable manner without the weight of the device and the manufacturing costs being substantially increased. This is achieved in that the fastening flange (7) has a multiplicity of holes (9) into each of which there protrude fastening bolts (10) which project on the smoothing plate (2), said fastening bolts being fixedly connected to the smoothing plate (2) on the one hand and being connected to the fastening flange (7) by means of a pressed connection on the other hand.

Description

TECHNICAL AREA

The invention relates to a device according to claim 1 and a smoothing trowel.
Such tools are used in construction to plaster walls with plaster or to apply other materials to other surfaces.

STATE OF THE ART

A smoothing trowel of the type mentioned is known from DE 29922317 U1.
Another smoothing trowel or device for smoothing and/or spreading plaster compounds by rubbing.

OBJECT

The object of the invention is to improve a device of the type mentioned above in such a way that the handle is connected particularly stably to the smoothing plate without substantially increasing the weight of the device, or the production costs.

SOLUTION

This object is achieved by means of a device having the features indicated in the characterizing part of claim 1 in conjunction with its above-mentioned features.

ADVANTAGES OF THE INVENTION

The device according to the invention provides a very stable tool, which is long-lasting and user-friendly. In addition, it provides an elegant design.

Advantageous Embodiments and Further Advantages

Further advantageous embodiments of the invention and the advantages thereof are characterized in the subclaims and are described below.
In an advantageous development of the device according to the invention, it is provided that each bolt has a shaped jacket surface, in particular comprising an external thread, or another surface, e.g. a corrugated jacket surface, which is so designed that during the pressing operation, the bolt is so compressed that the molded jacket surface is pressed against an inner surface of the holes to provide a pression connection. In this case, a bolt head, which protrudes out of the holding element, is screwed before the connection of the smoothing plate, so that the bolt widens and forms a very robust form-fitting and friction-locking connection with the holding element.
In a further advantageous embodiment of the invention, the hole consists of a first lower hole section that is adjacent to the smoothing plate and has a first diameter to receive a bolt foot, a second central hole section with a smaller diameter than the first hole section to receive a bolt clamping section of the bolt, and a third upper hole section having the smallest bore diameter to receive a compression section of the bolt. The enlarged connection surface of the bolts ensures a form-fitting, robust welding connection of the bolts with the smoothing plate. The narrow part protruding from the corresponding hole of the holding element before the pressing operation, is optimally shaped through the smaller mass so that it is flush with the holding element.
A further very significant improvement for the technical implementation of an elegant and individual design of the smoothing trowel lies in the fact that the holding element is made in one piece from a casting, wherein the mounting flange is I-shaped while the handle fastening section is L-shaped. A marking surface may be created by means of a suitable casting mold, in particular in a transition region between the holding element and handle, in order to print, stamp or otherwise make a mark or the like.
For this purpose, it is particularly advantageous if the handle fastening section comprises a flat, droplet-shaped transition piece extending in cross-section in the direction of the holding element, wherein the transition piece comprises a foot part and a head piece from which a shank, running approximately parallel to the holding element, continues with a twist-proof profile, which carries a threaded part on the head piece of the transition piece for screwing on a nut, wherein a handle part is fixed to be twist-proof between the head piece and the nut. This embodiment also improves the ergonomic function through the selection of a suitable grip material, in particular cork. Cork material is particularly convenient. The grip may be further improved by means of suitable depressions in the cork material.
It is advantageous when the holding element comprises a ground upper side. This improves the processing of plaster material.
Smoothing trowels are particularly suitable for plastering, in particular for fine plastering work, where the smoothing plate has an elongated and rectangular shape, with a length of, for example, a maximum of 32 cm and a width of, for example, 12 cm. Larger dimensions are also possible. In addition, a device with a toothed smoothing plate, as customarily used for the application of tiles in tile work, are likewise possible.
In order to implement a very individual design while, on the other hand, optimizing the handling of the smoothing compound, it is particularly advantageous if the smoothing plate has longitudinal grinding on its smoothing side and on both longitudinal sides, and a transverse grinding at right angles to the longitudinal grinding, wherein the cross-section of the smoothing plate preferably tapers into a wedge shape in the region of the longitudinal sides so that the smoothing side is angled at the longitudinal edges.
A device or smoothing trowel according to the invention may be easily produced when each bolt has a widened bolt lower side welded to the fastening side of the smoothing plate and a bolt head protruding from the fastening flange, wherein, following a pressing step, this bolt lies flush with the upper side of the fastening flange, and the bolt is so widened by the pressing force acting on the upper side that it forms a form-fitting and friction-locking connection with the fastening flange.
During production, care must be taken that the corrugated jacket surface of each bolt is pressed into the bore by the contact pressure acting on the bolt upper side in order to provide a form-fitting and friction-locking connection of the fastening flange with the smoothing plate.

EXEMPLARY EMBODIMENT

An exemplary embodiment is explained in more detail with reference to the drawings, in which further advantageous further developments of the invention and advantages thereof are described:

FIG. 1 shows a perspective view of a device according to the invention and a smoothing trowel in the mounted state,

FIG. 2 shows a further perspective view of the smoothing trowel in the mounted state from a different viewing angle.

FIG. 3 shows a cross-sectional view of a fastening flange with a bolt in the transverse section,

FIG. 4 shows a cross-sectional view of the fastening flange without bolts in the longitudinal section,

FIG. 5 shows a perspective view of the smoothing trowel without handle;

FIG. 6 shows a perspective view of the flat blade with the handle pulled apart, and

FIG. 7 shows a representation of bolt from the side.

FIG. 1 shows a device 1 for smoothing and/or spreading plaster compounds. Such a device 1 is also referred to as a smoothing trowel. The device 1 comprises a smoothing plate 2 with a smoothing side 3, which is indicated in FIG. 2, and comprises a fastening side 4 as well as a handle 5. Furthermore, the device 1 is provided with a holding element 6 connecting the handle 5 and the smoothing plate 2 on the fastening side 4, which is shown in a sectional view of a first and a second position in FIGS. 3 and 4. The holding element 6 has a fastening flange 7 to fasten the smoothing plate 2 and a handle fastening section 8.
The mounting flange 7 has a multiplicity of openings or holes 9 (FIG. 4), into each of which fastening bolts 10 protrude on the smoothing plate 2, as illustrated in FIGS. 3 and 7. On the one hand, each bolt is fixedly connected to the smoothing plate 2 while, on the other hand, each is connected by a pressed connection to the fastening flange 7, as shown in FIGS. 3 and 5.
As shown in FIG. 7, each bolt 10 has an outer thread or a differently shaped outer surface 11, e.g. corrugated, which is so designed that during the pressing operation, the bolt 10 is compressed to the shape shown in FIG. 3. As a result, the corrugated jacket surface 11 is pressed against an inner surface 12 (FIG. 4) of the holes 9 to create the pressed connection respectively shown in FIG. 3 and FIG. 5.
FIG. 4 also shows that the hole 9 comprises a first lower hole section 13 with a first diameter adjacent to the smoothing plate 2, to receive a bolt foot 14 (FIG. 7)
FIG. 4 further shows that the hole 9 has a second central hole section 14 with a smaller diameter than the first hole section 13. This hole section 13 is provided to receive a bolt clamping section 15 of the bolt 10.
In addition, the hole 9 has a third upper hole section 16 with the smallest hole section to receive a compression section 17 of the bolt 10, wherein this section is shown in the un-shaped state in FIG. 7.
The holding element 6 is integrally made from a casting, wherein the mounting flange 7 is I-shaped, while the handle fastening section 8 is L-shaped, as shown in FIGS. 5 and 6.
The handle fastening section 8 comprises a flat droplet-shaped transition piece 18 which widens in cross-section in the direction of the fastening flange 7. The transition piece 18 in turn comprises a foot part 19 and a head piece 20 from which a shank 21 extends approximately parallel to the fastening flange 7 to a twist-proof profile 22. The profile may be a stepped profile with four spikes 23 (FIG. 5) or five spikes, or, e.g. a triangular to hexagonal profile. The key aspect is that it is twist-proof.
A thread 24 (FIG. 5) is provided on the head piece 20 of the transition piece 18 (FIG. 6) for screwing on a nut 25, which may be seen in FIG. 1. A handle 26 is fixed in a twist-proof manner between the head piece 20 and the nut 25. The fastening flange 7 of the holding element 6 has a ground upper surface which provides a smooth surface 27 with the bolt heads 30. From above, the bolt heads 30 are seen merely as circles, which provides distinctiveness compared with other products.
As shown in FIG. 1, the smoothing plate 2 has an elongated and rectangular shape.
Since the smoothing plate has a longitudinal grinding on its smoothing side and on both longitudinal sides, while the smoothing side has a transverse grinding that is perpendicular to the longitudinal grinding, wherein the cross-section of the smoothing plate preferably tapers outwards in a wedge-shaped manner in the region of the longitudinal sides, so that the smoothing side is angled at the longitudinal edges. The smoothing plate is produced as follows:
First Step:
Each bolt 10 is welded to the fastening side 4 of the smoothing plate 2 by means of a widened bolt lower side 28. A row of bolts 10 are aligned corresponding to the hole arrangement of the fastening flange 7. Advantageously, there are from four to twenty bolts, e.g. twelve bolts.
Second Step:
The holding element 6 is positioned with its fastening flange 7 on the smoothing plate 2 so that the bolts 10 are inserted into the holes 9.
Third Step:
The bolt heads 30 (FIG. 7) protruding from the fastening flange 7 are pressed with a force from above until they assume the form shown in FIG. 3. After the pressing step, the bolts 10 lie flush with the upper side of the fastening flange 7. By the contact pressure acting on the upper side of the bolt heads 30, each bolt 10 is so widened that it forms a form-fitting and friction-locking connection with the fastening flange 7, as shown in FIG. 3.
Fourth Step:
In a fourth step, the surface 27 or upper side of the bolt of the fastening flange is ground.
As a result of the pressing of the compression pressure acting on the upper side of the bolt 31, i.e. the corrugated surface 11 of each bolt 10, the latter engages in the holes 9 to provide a form-fitting and friction-locking connection of the fastening flange 7 to the smoothing plate 2, as shown in FIG. 3
In the un-shaped state, the bolts preferably have a thread diameter M5 in the central section, a diameter of 6 to 7 mm in the lower section, for example 6.5 mm, and a diameter of 4 to 5 mm, e.g. 4.4 mm, in the upper section.
The hole 9 preferably has a diameter of 4.2 to 5.5 mm, e.g. 4.8 mm, in the upper section, a thread diameter of 4.95 to 5.05 mm in the central section, and a diameter of 9 to 10 mm, e.g. 9.5 mm in the lower section.
In addition, the smoothing plate has a longitudinal grinding on its smoothing side 3 and on both longitudinal sides, and a transverse grinding on its smoothing side 3, which is perpendicular to the longitudinal ground plane, i.e. transversely directed, wherein the cross-section of the smoothing plate narrows in a wedge-shaped manner in the region of the longitudinal sides so that the smoothing side is angled at the longitudinal edges

LIST OF REFERENCE NUMERALS

1 Device
2 Smoothing plate
3 Smoothing side
4 Fastening side
5 Handle
6 Holding element
7 Fastening flange
8 Handle fastening section
9 Holes
10 Fastening bolts
11 Jacket surface
12 Interior surfaces
13 Hole section
14 Bolt foot
15 Bolt clamping section
16 Hole section
17 Compression section
18 Transition piece
19 Foot part
20 Head piece
21 Shank
23 Teeth
24 Threaded piece
25 Nut
26 Handle
27 Surface
30 Bolt heads
31 Bolt upper side

Claims

1. A device (1) for smoothing filling or plaster compounds and/or for spreading them by rubbing, comprising a smoothing plate (2) with a smoothing side (3) and a fastening side (4), a handle (5) and a holding element (6) which connects the handle (5) and the smoothing plate (2) on the fastening side (4), wherein the holding element (6) has a fastening flange (7) for fastening the smoothing plate (2), and a handle-fastening section (8), characterized in that the fastening flange (7) has a multiplicity of holes (9) into each of which there protrude fastening bolts (10) which project on the smoothing plate (2), wherein the fastening bolts are fixedly connected to the smoothing plate (2) on the one hand and connected to the fastening flange (7) by means of a pressed connection on the other hand.

2. Device according to claim 1, characterized in that each bolt has a shaped jacket surface (11), in particular an external thread, which is so designed that upon compressing the bolt (10), the shaped jacket surface (11) is pressed against the inner surfaces (12) of the holes (9) to provide a pressed connection.

3. Device according to claim 1, characterized in that the hole (9) consists of a first lower hole section (13) with a first outer diameter adjacent to the smoothing plate (2) to receive a bolt foot (14), a second central hole section (14 b) with a smaller diameter than the first hole section 13 to receive a bolt clamping section 15 of the bolt (10), and a third upper hole section 13 having the smallest hole section 16 to receive a compression section (17) of the bolt (10).

4. Device according to claim 1, characterized in that the holding element (6) is made in one piece from a casting, wherein the fastening flange (7) is I-shaped and the handle fastening section (8) is L-shaped.

5. Device according to claim 1, characterized in that the handle fastening section (8) comprises a flat droplet-shaped transition piece (18) widening in cross-section in the direction of the fastening flange (7), wherein the transition piece (18) comprises a foot part (19) and a head piece (20) from which a shank (21) with a twist-proof profile (22) extends approximately parallel to the fastening flange (7), wherein the transition piece (18) carries a threaded piece (24) for screwing on a nut (25), wherein a handle (26) is secured twist-proof between the head piece (20) and the nut (25).

6. Device according to claim 1, characterized in that the fastening flange (7) of the holding element (6) has a ground upper surface.

7. Device according to claim 1, characterized in that the smoothing plate (2) has an elongated and rectangular shape.

8. Device according to claim 1, characterized in that the smoothing plate (2) has a longitudinal grinding on its smoothing side (3) and on both longitudinal sides, and a transverse grinding perpendicular to the longitudinal grinding, i.e. transversely directed, on the smoothing side (3), wherein the cross-section of the smoothing plate (2) tapers outwards in a wedge shape in the region of the longitudinal sides so that the smoothing side is angled at the longitudinal edges.

9. Method for the production of a device according to claim 1, characterized in that each bolt (10) has a widened lower side of the bolt, which is welded on the fastening side (4) of the smoothing plate (2), wherein each bolt (10) comprises a bolt head (30) protruding from the fastening flange (7), wherein, following a pressing step, the bolt head (30) is flush with the upper side of the fastening flange (7), and wherein the bolt is widened by the contact pressure acting on the upper side to form a form-fitting and friction-locking connection with the fastening flange 7.

10. Method according to claim 9, characterized in that the corrugated jacket surface of each bolt is pressed into the hole by means of the contact pressure acting on the upper side of the bolt to give a form-fitting and friction-locking connection of the fastening flange with the smoothing plate.

11. Device according to claim 2, characterized in that the holding element (6) is made in one piece from a casting, wherein the fastening flange (7) is I-shaped and the handle fastening section (8) is L-shaped.

12. Device according to claim 3, characterized in that the holding element (6) is made in one piece from a casting, wherein the fastening flange (7) is I-shaped and the handle fastening section (8) is L-shaped.

13. Device according to claim 2, characterized in that the handle fastening section (8) comprises a flat droplet-shaped transition piece (18) widening in cross-section in the direction of the fastening flange (7), wherein the transition piece (18) comprises a foot part (19) and a head piece (20) from which a shank (21) with a twist-proof profile (22) extends approximately parallel to the fastening flange (7), wherein the transition piece (18) carries a threaded piece (24) for screwing on a nut (25), wherein a handle (26) is secured twist-proof between the head piece (20) and the nut (25).

14. Device according to claim 3, characterized in that the handle fastening section (8) comprises a flat droplet-shaped transition piece (18) widening in cross-section in the direction of the fastening flange (7), wherein the transition piece (18) comprises a foot part (19) and a head piece (20) from which a shank (21) with a twist-proof profile (22) extends approximately parallel to the fastening flange (7), wherein the transition piece (18) carries a threaded piece (24) for screwing on a nut (25), wherein a handle (26) is secured twist-proof between the head piece (20) and the nut (25).

15. Device according to claim 4, characterized in that the handle fastening section (8) comprises a flat droplet-shaped transition piece (18) widening in cross-section in the direction of the fastening flange (7), wherein the transition piece (18) comprises a foot part (19) and a head piece (20) from which a shank (21) with a twist-proof profile (22) extends approximately parallel to the fastening flange (7), wherein the transition piece (18) carries a threaded piece (24) for screwing on a nut (25), wherein a handle (26) is secured twist-proof between the head piece (20) and the nut (25).

16. Device according to claim 2, characterized in that the fastening flange (7) of the holding element (6) has a ground upper surface.

17. Device according to claim 3, characterized in that the fastening flange (7) of the holding element (6) has a ground upper surface.

18. Device according to claim 4, characterized in that the fastening flange (7) of the holding element (6) has a ground upper surface.

19. Device according to claim 5, characterized in that the fastening flange (7) of the holding element (6) has a ground upper surface.

20. Device according to claim 2, characterized in that the smoothing plate (2) has a longitudinal grinding on its smoothing side (3) and on both longitudinal sides, and a transverse grinding perpendicular to the longitudinal grinding, i.e. transversely directed, on the smoothing side (3), wherein the cross-section of the smoothing plate (2) tapers outwards in a wedge shape in the region of the longitudinal sides so that the smoothing side is angled at the longitudinal edges.