FORMWORK TIE

Abstract

A tie rod of a formwork tie for connecting two formwork elements, which are disposed opposite and at a distance from one another, is provided with two opposing flattened regions, and a tie nut is provided with a radial fixing screw, which can optionally be screwed against one of the two flattened regions for securing the tie nut on the tie rod, whereby the distance between the two formwork elements can be set in steps of one half a lead of an external thread of the tie rod.

Claims

1. A formwork tie for connecting two formwork elements that are disposed opposite and at a distance from one another, comprising a tie rod, which includes an external thread, and a tie nut, which has a through-hole including a first internal thread, by way of which the tie nut is screwed onto the external thread of the tie rod, wherein the tie rod comprises a flattened region extending in a longitudinal direction of the tie rod at a circumferential location, and the tie nut comprises a fixing element, which can be adjusted transversely to the flattened region of the tie rod and act on the flattened region such that the fixing element holds the tie nut non-rotatably on the external thread of the tie rod.

2. The formwork tie according to claim 1, wherein the tie rod comprises a plurality of flattened regions that extend in the longitudinal direction of the tie rod and are distributed across a circumference of the tie rod.

3. The formwork tie according to claim 2, wherein the tie rod comprises two flattened regions that extend in the longitudinal direction of the tie rod and are disposed opposite one another on the tie rod.

4. The formwork tie according to claim 1, wherein the turns of a convolution of the external thread of the tie rod comprise flattened regions at the outer circumference thereof, on which the fixing element can act so as to hold the tie nut non-rotatably on the external thread of the tie rod.

5. The formwork tie according to claim 1, wherein the fixing element is a screw element, and the tie nut includes a second internal thread, into which the fixing element is screwed and which opens into the through-hole of the tie nut, so that, in a rotational position of the tie nut on the external thread of the tie rod, the fixing element can be screwed against the flattened region of the tie rod so that the fixing element holds the tie nut non-rotatably on the tie rod.

6. The formwork tie according to claim 5, wherein the second internal thread extends radially with respect to the through-hole including the first internal thread of the tie nut.

7. The formwork tie according to claim 1, wherein the external thread of the tie rod has a pitch of 10 mm.

8. The formwork tie according to claim 1, wherein the tie rod includes distance markings for the distance of the formwork elements set by way of the tie nut and/or distance range information for a distance of the formwork elements settable by way of the formwork tie.

9. The formwork tie according to claim 4, wherein the tie rod includes distance markings for the distance of the formwork elements set by way of the tie nut and/or distance range information for a distance of the formwork elements settable by way of the formwork tie, and the distance markings are disposed at the flattened regions of the convolution.

10. The formwork tie according to claim 1, wherein the tie rod comprises a smooth-walled and conical rod section, the end of which having the larger diameter faces the external thread of the tie rod.

11. The formwork tie according to claim 1, wherein the formwork tie comprises an abutment for a rear side, facing away from the other formwork element, of the one formwork element which is pivotably supported in all directions at the tie nut.

Description

[0020] The invention will be described hereafter in greater detail based on one exemplary embodiment shown in the drawings. In the drawings:

[0021] FIG. 1 shows a formwork tie according to the invention in a perspective illustration;

[0022] FIG. 2 shows a side view of the formwork tie from FIG. 1;

[0023] FIG. 3 shows a side view of the formwork tie from FIG. 1 in an illustration that is rotated 90° compared to FIG. 2;

[0024] FIG. 4 shows an enlarged illustration of a detail according to circle IV of FIG. 2;

[0025] FIG. 5 shows an enlarged illustration of a detail according to circle V of FIG. 2;

[0026] FIG. 6 shows a tie rod of the formwork tie from FIG. 1 in a side view, with the same viewing direction as in FIG. 2;

[0027] FIG. 7 shows the tie rod of the formwork tie from FIG. 1 in a side view, with the same viewing direction as in FIG. 3;

[0028] FIG. 8 shows a tie nut comprising an abutment of the formwork tie from FIG. 1 in a front view; and

[0029] FIG. 9 shows the tie nut comprising the abutment of the formwork tie from FIG. 1 in an axial section.

[0030] The formwork tie 1 according to the invention shown in FIGS. 1 to 3 is intended for connecting two non-illustrated formwork elements, which are disposed opposite and at a distance from one another. The formwork elements comprise a board made of plywood or plastic, serving as the formwork shell, and a panel made of longitudinally and transversely extending rectangular tubes made of steel or aluminum on a rear side of the formwork shell for reinforcing the formwork shell. The rear side is the side of the formwork shell at which the panel is disposed. The two formwork elements are set up with the formwork shells thereof facing one another.

[0031] The formwork tie 1 comprises a tie rod 2, which is shown in FIGS. 6 and 7, and a tie nut 3 comprising an abutment 4, which is shown in FIGS. 8 and 9.

[0032] The tie rod 2 includes two external threads 5, 6, between which a smooth-walled, conical rod section 7 is situated. The tie nut 3 can be screwed, or is screwed, onto the external thread 5 at an end of the conical rod section 7 which has a larger diameter, the tie nut for this purpose including an axial through-hole 8 including a first internal thread 9.

[0033] Turns of a convolution 10 of the external thread 5 at the end of the conical rod section 7 of the tie rod 2 which has the larger diameter include circular segment-shaped recesses at opposing circumferential locations of the external thread 5 or of the tie rod 2 in all turns, which is to say across a length of the external thread 5. In this way, planar surfaces on outer circumferences of the turns of the convolution 10 are formed in two chordal surfaces of the tie rod 2 which are parallel to one another and parallel to an axial plane of the tie rod 2 at the opposing circumferential locations of the external thread 5 or of the tie rod 2. These planar surfaces form flattened regions 11 of the tie rod 2 at the opposing circumferential locations of the tie rod 2, which extend across the length of the external thread 5. In the exemplary embodiment, the recesses of the turns of the convolution 10 forming the flattened regions 2 are as deep as the convolution 10 is high, so that the two flattened regions 11 are interrupted at the opposing circumferential locations of the tie rod 2 between the turns of the convolution 10.

[0034] The tie nut 3 is a wing nut comprising two radially projecting wings 12 to be rotatably driven by way of hammer blows. The tie nut 3 additionally comprises a hexagon 13 to be rotatably driven by way of an open-end wrench or the like, coaxially in a center between the wings 12. Nuts other than wing nuts are possible.

[0035] Radially with respect to the through-hole 8 including the first internal thread 9, the tie nut 3 includes a radial hole 14 including a second internal thread 15, which opens into the through-hole 8. A screw is screwed into the second internal thread 15 as a fixing screw 16, which can be screwed from the outside against one of the two opposing flattened regions 11 at the external thread 5 of the tie rod 2, so that the inner end thereof, facing the tie rod 2, strikes against the flattened region 11 and holds the tie nut 3 non-rotatably on the tie rod 2. This requires the tie nut 3 to have previously been rotated into a position on the external thread 5 in which the radial hole 14 is aligned with one of the two flattened regions 11 of the tie rod 2 in such a way that the fixing screw 16 strikes against one of the two flattened regions 11. When the fixing screw 16 does not strike perpendicularly against the flattened region 11 from the outset, the fixing screw aligns automatically perpendicularly with the flattened region 11, thereby turning the tie nut 3 slightly on the external thread 5 of the tie rod 2.

[0036] The fixing screw 16 can, generally speaking, also be interpreted as a fixing element. In the exemplary embodiment, the fixing screw 16 is an eyelet bolt, but other screws or fixing elements other than a fixing screw 16 are also possible, for example a stud-shaped fixing element that, for example, acts from the outside on the flattened region 11 of the tie rod 2 in a spring-loaded manner so as to hold the tie nut 3 non-rotatably on the tie rod 2. The list is by way of example and not exhaustive.

[0037] The tie nut 3 can in each case be fixed on the tie rod 2 by way of the fixing screw 16 after half a revolution by screwing the fixing screw 16 against one of the two opposing flattened regions 11 of the tie rod 2. In this way, it is possible to fix the tie nut 3 on the tie rod 2 in steps of half a lead of the external thread 5. The formwork tie 1 according to the invention thus allows the distance of the two formwork elements that are disposed opposite one another to be set in steps that correspond to half a lead of the external thread 5 of the tie rod 2.

[0038] In the exemplary embodiment, the external thread 5 of the tie rod 2 has a lead of 10 millimeters, so that it is possible to set the tie nut 3, and thus the distance of the two formwork elements, in steps of 5 millimeters.

[0039] As is apparent from FIG. 4, numbers are provided in the planar surfaces at the circumference of the turns of the convolution 10 of the external thread 5 on the one side of the tie rod 2, which indicate the distance of the two formwork elements set by way of the tie nut 3, which is to say a clearance of the formwork shells of the formwork elements. This distance corresponds to a wall thickness of the wall to be poured using the formwork elements. In the exemplary embodiment, the numbers in the planar surfaces of one of the two flattened regions 11 indicate the distance in millimeters and can, generally speaking, also be interpreted as distance markings 17.

[0040] For rotation, the tie rod 2 includes a hexagon at an end of the external thread 5 which faces away from the smooth-walled, conical rod section 7 and the width across the corners of which is smaller than a minor diameter of the external thread 5, so that the tie nut 3 can be screwed on. As is apparent from FIG. 5, number range information is provided at the hexagon, which indicates a smallest and a largest distance of the formwork shells settable by way of the formwork tie 1. The number range information can, generally speaking, also be interpreted as distance range information 18.

[0041] The tie nut 3 comprises a ball-shaped section 19, which is coaxial with respect to the through-hole 8 including the first internal thread 9 and is accommodated in a hollow spherical receptacle 20 of the abutment 4 of the formwork tie 1. The ball-shaped section 19 in the hollow spherical receptacle 20 forms a ball and socket joint, by way of which the abutment 4 can be pivoted with respect to the tie nut 3 and with respect to the tie rod 2 in all directions about a center of the ball-shaped section 19, serving as the pivot point. As a result, the abutment 4 automatically aligns at a formwork element when the tie rod 2 runs obliquely with respect to the formwork element.

[0042] The abutment 4 has the shape of a plate from which a collar 21 projects, which includes the hollow spherical receptacle 20. From the hollow spherical receptacle 20, an aperture continues through the plate of the abutment 4, through which the tie rod 2 passes.

[0043] At a radial distance from the collar 21, the plate of the abutment 4 has an elongated hole, which is radial with respect to the collar 21 and in which a fastening screw 22 is accommodated perpendicularly to the plate of the abutment 4, which is displaceable in the elongated hole, so that the distance thereof with respect to the collar 21, and thus with respect to the tie nut 3, can be set. The abutment 4 can be secured at an internal thread of the panel of the formwork element by way of the fastening screw 22.

[0044] So as to connect the two non-illustrated formwork elements disposed opposite and at a distance from one another, the tie rod 2 is placed through a through-hole in one of the two formwork elements until this bears against the abutment 4 at the rear side of the formwork element, where the abutment 4 can be secured by way of the fastening screw 22. Before or after the tie rod 2 has been placed through the hole in the formwork element, the distance of the two formwork elements with respect to one another can be set by turning the tie nut 3 on the tie rod 2 or by turning the tie rod 2 in the tie nut 3. So as to turn the tie nut 3 or the tie rod 2, the fixing screw 16 has to be screwed radially so far to the outside that the tie nut 3 can be rotated on the external thread 5 of the tie rod 2. When the distance has been set, the fixing screw 16 is rotated inwardly so as to strike against one of the two flattened regions 11 and hold the tie nut 3 non-rotatably on the tie rod 2, and thereby secure the set distance of the two formwork elements with respect to one another.

[0045] The tie rod 2 is also placed through a hole in the formwork element disposed on the opposite side, at the rear side of which a nut is disposed, for example, into which the external thread 6 on the side of the smooth-walled, conical rod section 7 of the tie rod 2 which has a smaller diameter is screwed, so that the two formwork elements are connected. The distance of the two formwork elements can be set by turning the tie nut 3 on the tie rod 2.

[0046] It is also possible to screw the nut onto the external thread 6 on the rear side of the other formwork element after the tie rod 2 has been placed through, provided that the rear side of the other formwork element is accessible.

[0047] Due to the smooth-walled, conical rod section 7, the tie rod 2 can be pulled out of or unscrewed from the concrete after the concrete has set.