GB2113343A

GB2113343A - Connector

Info

Publication number: GB2113343A
Application number: GB08234488A
Authority: GB
Inventors: Trygve Theodorsen
Original assignee: Bulldog AS
Current assignee: Bulldog AS
Priority date: 1981-12-04
Filing date: 1982-12-03
Publication date: 1983-08-03
Also published as: NO814164L; CH659278A5; SE8206875D0; DK537582A; DE3244846A1; BE895217A; FR2517770A1; GB2113343B; NL8204679A; LU84505A1; SE8206875L

Abstract

A connector for timber manufactured by welding a number of pegs or dowels 2 without heads to a base plate 1 spaced apart, so that imbedded in wood they can transfer loads from the wood to the base plate 1. The dowels 2 may be welded to one or both sides of the plate 1, may have different forms, and may be arranged in groups or singly. <IMAGE>

Description

SPECIFICATION Connector for timber The present invention relates to the construction and mounting of a connector for timer intended for use in wooden constructions.

Connectors for timber are already known that are cast in one piece as a plate having upright teeth or a ring around the edge and these are inserted into pre-moulded recesses in the wood material. There are furthermore known connectors for timber manufactured by stamping out teeth in a thin plate, the teeth being bent at right angle to the plate and pressed into the wood material by mounting.

Common for all connectors for timber is the fact that they are used in combination with bolts and nuts to keep the wooden parts assembled because the teeth of the connectors, the ring and so on have little resistance against withdrawing.

The said known types of connectors for timber are, owing to the cost of the tools needed to produce them, manufactured only in a limited number of modifications and owing to productional reasons only in a limited range of forms. Consequently, the loadbearing capacity of the wooden members cannot always be fully utilized.

An object of the present invention is to provide a new and improved connector for timber giving more possible forms and greater capacity.

The invention provides a connector for timber, comprising a number of pegs or dowels without heads so fixed by welding to a base plate at right angles to the base plate and spaced a certain distance apart that if imbedded in a wooden beam they may transfer loads from the wood material to the base plate.

Various forms of connector constructed in accordance with the invention will now be described by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a first form of connector in plan, sectional and axonometric view; Figure 2 shows schematically the manufacture of a connector; Figure 3 shows the first form of connector in cross section and a connection using a plurality of bolts; Figure 4 is a section through a second form of connector; Figure 5 shows various forms of pin for use in the connectors; and Figure 6 is a section through a third form of connector.

Referring to the drawings, the connectors comprise pegs or dowels 2 without a head attached rigidly at a right angle to the base plate 1 using a bolt-welding technique (see Fig. 2).

The base plate may consist of any electrically conducting material, for example, steel, aluminum, brass, copper and so forth. The dowels may likewise consist of the same ma trials. Depending on their weldability, the plate and the dowels may be of a different material. The plate comprises an aperture 3 for a throughgoing bolt 4 (Fig. 3).

In order to mount the connector, bores or recesses 5 are drilled in a wooden beam using template in a pattern corresponding to the positioning of the dowels and bolts.

Depending on the thickness of the base plate 1 and the requirements of the connection, the plate may be set into the wooden beams 6 so that there will be no gap between them.

The connector is placed in the bores in one wooden beam 6 with the dowels 2 protruding downwards and with a double-sided connector an other wooden beam is put down on the opposed dowels, the bolt, with discs or washers 7, is passed through and the nut is fastened. The connector may have several apertures 3 so that more than one bolt 4 can be passed through the same connector.

For the connection of a wooden beam to concrete, steel and so forth the base plate 1 is equipped with dowels on only one side (see Fig. 4). The aperture 3 for the bolt 4 is formed with a collar 8 in order to take higher loads, or the base plate 1 is made thick enough that the allowable pressure is not surpassed by the load on the edge of the aperture.

The dowels may be cylindrical, threaded cylindrical, hollow with internal threads, conical, cruciform, chiselformed and so forth as shown at 2ato 2f in Fig. 5.

The dowels may have fracture indications, as shown at 2g, so that they can be broken off to a predetermined length.

By means of such dowels a double-sided connector may be constructed inside a wooden beam, the base plate being introduced into a slit in the beam and the dowels being welded to the plate through predrilled holes in the wood. The base plate may have an extension outside the beam for transfer of the load to a second supporting element.

Large one-sided connectors for timber may be provided by welding, with externally threaded dowels 9 on the back side as shown in Fig. 6, so that these, passing, for instance, through a junction plate 10 in addition to the throughgoing bolt, may significantly improve the load transfer.

By correct welding the dowels can be made to melt into the base plate to form a rigid monolithic unit.

A loaded dowel will tend to turn the plate.

This, however, is fixed between the wooden beams, or between the wooden beam and the steel plate, as the case may be. The bolt will retain the parts assembled. The adjacent dow els in the direction of the force will tend to turn the plate the opposite way and thus add to reduction of the deformation.

In a double-sided connector having relatively long dowels, two opposed dowels will form one long rod-like dowel. Owing to the fixing of the base plate the rod-like dowel will for a certain diameter and thickness of the wood material have the total of four floating elements. In this case the capacity of the rodlike dowel will be maximally utilized.

The base plates may be produced by simple cutting operations and thus may rationally be manufactured even in small production runs.

In large runs and with a complicated form they may most advantageously be stamped out of a strip.

Being planar they can be stored easily.

From the store the plates are carried to a jig, wherein the dowels are fixed by welding.

Electronic control of the welding operation safeguards the quality of the welding, while the welding tool may be guided to its correct position by numerical or data based guiding.

Dowels are automatically supplied to the welding tool.

For both double-sided and one-sided connectors for timber according to the invention the thickness and form of the base plate may be freely chosen and similarly the diameter, length, cross-section and mutual position of the dowels may be accommodated so that the maximum capacity for transfer of loads may be obtained, having regard to the load, the thickness and width of the wooden beams, and their mutual angle and thus the contact surface.

Claims

1. A connector for timber, comprising a number of pegs or dowels without heads so fixed by welding to a base plate at right angles to the base plate and spaced a certain distance apart that if imbedded in a wooden beam they may transfer loads from the wood material to the base plate.

2. A connector as claimed in claim 1, wherein the base plate and the dowel are manufactured from electrically conducting material or from a combination of such materials.

3. A connector as claimed in claim 1 or claim 2, comprising dowels so welded to both sides of the plate that if the dowels on one side are imbedded in a wooden beam and the dowels on the other side are imbedded in another wooden beam loads may be transferred from one beam to the other and wherein in use the two beams may be retained together by a bolt passing through a bore in the connector and a nut.

4. A connector as claimed in claim 1 or claim 2, comprising dowels welded to one side of the base plate and wherein the base plate has a central aperture with a close fit on a retaining bolt.

5. A connector as claimed in claim 4, wherein the central aperture is formed with a collar to reduce the pressure at the edge of the bore as loads are transferred from the connector to a central bolt.

6. A connector as claimed in any one of claims 1 to 5, wherein the dowels are substantially cylindrical and square ended.

7. A connector as claimed in any one of claims 1 to 5, wherein the dowels are cylindrical having external or internal threads or grooves, conical, sharpened, cruciform, chiselshaped or the like.

8. A conector as claimed in claim 7, wherein the dowels have a short straight cylindrical portion nearest to the base plate in order to be clamped in a welding tool.

9. A connector as claimed in any one of claims 1 to 8, wherein the dowels have fracture indications so that they may be broken, or were broken at fracture indications.

10. A connector as claimed in claim 9, that has been manufactured inside a wooden member by inserting the base plate into a slit in the wood and fixing the dowels by welding through holes drilled in the wood.

11. A connector as claimed in claim 10, wherein the base plate has an extension outside the beam for attachment to another supporting element.

1 2. A connector as claimed in any one of claims 1 to 11, comprising different types of dowels welded to the same base plate.

1 3. A connector as claimed in claim 1 2, having welded on its back side one or more threaded dowels which may be secured through holes in a junction plate by nuts and which may transfer loads from the connector to the junction plate.

14. A connector as claimed in any one of claims 1 to 13, wherein the dowels are fixed by welding in groups on a common base plate having greater thickness, so that the base plate can itself form a junction plate between two or more wooden parts.

1 5. A connector substantially as hereinbe fore described with reference to, and as shown in, Fig. 1, or Fig. 3, or Fig. 4, or Fig.

6 of the accompanying drawings.

16. A connector as claimed in claim 15, having pins or dowels of any one or more types substantially as hereinbefore described with reference to, and as shown in, Fig. 5 of the accompanying drawings.