FI122708B - Method and apparatus for making joints - Google Patents

Description

This invention relates to a method and apparatus for making joints. In particular, 5 are not, however, exclusively joints used in the furniture industry to connect pieces of furniture to one another.

The furniture industry uses a wide variety of joints, some of which are, for example, the salmon tail joint. Said joint is made by machine as female part 10 and male part which are glued together. Joints are durable, but very expensive to make, as is the relatively difficult way of joining them, for example when assembling pieces of furniture at home.

Other conventional methods include various screw connections. For example, a second piece of attachment-15 is drilled with a hole for a connecting screw. The screw enters the bore in the counterpart, which ends in a transverse bore, where the counter-threaded counterbore is inserted. This type of joint is quite sturdy but relatively laborious and sometimes it is difficult to fit the screw and the counterpart.

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Numerous other types of joints are also known for hanging a cabinet on a wall, for example, using a screw and a taper with a tapered elongated hole. Many such joints require embedding of metal joints in the structure. Many times the metal piece to be submerged is shaped such that submersion is a very demanding operation.

It is an object of the present invention to provide a method and a device that solves most of the weaknesses that hamper the above-mentioned prior art solutions and which, for example, allow furniture to be assembled very quickly in a durable manner.

The above and other advantages and advantages of the present invention are achieved as set forth in the appended claims.

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A preferred embodiment of the invention will now be described in more detail with reference to the accompanying drawings.

Figure 1 is an axonometric view of one embodiment of the invention; 5

Figure 2 is a sectional view of the device of Figure 1;

Figure 3 is a side view of said device; Figure 4, in turn, shows said device as seen directly from above;

Figure 5 is a view illustrating the formation of a joint; and Figs. 6a and 6b show the joint structure in open and closed versions.

As a first remark, the device shown in Figs. 1-4 above is a part to be placed in a second attachment piece, the second part of which is a counter piece in the second attachment piece, which is a screw with a 20 socket. This is not illustrated in Figures 1-4 either. Instead, Figures 5 and 6 also show a connecting screw.

A functional assembly is formed only by two separate parts 2 and 3, which are immersed in the piece to be joined so that the outer surface of the part 2 is in the plane of the piece to be joined. Of course, a screw to be attached to the other piece 9 to be joined, the head of which sits in the corresponding opening in part 2, is also required for the finished connection.

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Cl As can be clearly seen in the figures, part 2 is substantially circular in cross section and has a diameter that is clearly larger than part 3. Thus, for fixing the parts I '- ° 30, two different boreholes are required, one from the surface,

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cm for the part 2 and the other deeper part of the bore for securing the part 2 by means of the screw-like part 3.

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As shown in particular in sectional view 2, the base 5 of the screw 3 is centrally located with respect to the assembly. In order to turn the screw, there is, for example, a recess suitable for a socket wrench. Obviously, the type of key to be used and the corresponding recess or groove type can be selected as desired. However, the Allen key is a high-torque and very common key, which makes it a good choice. In Figure 2, the surface of the piece to be joined is indicated by a dashed line. It is thus very clear that the embedding of part 2 takes place substantially up to the surface of the body.

The retaining effect of the screw member 3 is achieved by making a suitable "shelf" or shoulder 10 on the upper member 2, on which the head of the screw 3 rests and against which the head 5 is pressed. As shown, the mounting assembly, which is embedded and tightened in its bores, is sure to be stationary. Figure 2 shows a preferred embodiment in which the head 5 of the screw 3 is embedded in the shelf 10 so that the surface of the shelf is flat as a result.

As can be clearly seen in the figures, part 2 is open in one direction. The upper slot serves to bring the socket 13 of the second engaging piece 12 (Fig. 5) into the locking position, and the lower portion forming the shoulder 10 acts to bring the screw 3 to the central position 2 for locking.

Referring specifically to Figures 5 and 6, as mentioned earlier, the joint consists of the above parts in one piece to be joined and almost

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£ 11.12 of the fully recessed screw member in one of the fasteners

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^ 25 published. In practice, this means that the second piece 12 to be connected is screwed, either drilling or directly into the piece, with a screw 11 in which T is the base 13 which is left above the surface of the piece for a well-defined dimension. The stock is particularly so-called. submerged base, whereby section 2 has oblique complementary surfaces corresponding to the oblique surfaces of the submerged base.

o & 30 o w The flange-like head 13 of the screw 11 of the attachment is thus at a certain height above the surface, as is clearly shown in Fig. 5. Figures 1, 2 and 4 illustrate how the groove visible from the inserted connection piece 2 is wider at one end to receive the screw 13 protruding from the surface 12 of the opposite piece to be correctly positioned to make the connection. The shaft 11 of said screw fits into the narrower portion of the slot in the position of the finished joint.

Figures 1 and 2 best illustrate the shape of the screw head assembly 5 in the fastener 1 or rather in part 2. Thus, the groove 7 to which the screw head is attached is preferably curved so that the head 13 fits snugly against the bottom of the groove 7 and against the trailing edge. In the case of a single joint, the screw-containing piece may possibly be slightly tilted to facilitate insertion of the screw head. With the screw head 10 in place, the surfaces of the two pieces to be joined are tight against each other and the joint is tight and durable.

Fig. 6 illustrates the positions of the connecting pieces first in Fig. 6a in the open state and then in Fig. 6b in the closed state, whereby the cap 15 13 of the screw 11 is slid into the slot and the joint is formed.

The joint according to the invention is openable, but requires some force to open. Opening can be made considerably more difficult or, if desired, even impossible by using the locking plate 4. This plate is slightly folded from the 20 sides as shown. The material of manufacture is especially spring steel or the like. The lock plate 4 is pushed in the arrow direction shown in Figure 1 on the securing screw, in which case the edges with serrations 8 holding the disk in place.

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^ 25 The narrow projections 9, 9 of the plate 4 remain slightly upwards from the horizontal. The area between the projections is curved to correspond to the other to be secured

The base 13 of the O-block fixing screw 11 has a shape. When the connection is made, the locking plate ir 4 holds the screw in place to prevent the connection from being dismantled.

In the practice of the invention, practical tests have been carried out on the durability of joints made with the joints according to the invention and these tests have clearly exceeded the durability standards set, for example, for furniture joints.

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Very common tools, such as those found in any woodworking economy and company, are sufficient to make the invention joint. No special work is required. Even drilling is easy and the end result is guaranteed because the drilling is concentric.

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Claims (8)

A method of making a joint between two pieces by means of a screw (11) provided with a head (13) which is placed in the first piece (12) to be connected and a tapered cutter (2) provided placed in the second piece and secured with a screw-like member (3) to a borehole in the second piece to be connected, characterized in that the counterpart (2) is provided with a cutter (7) intended for the head (13) the screw (11) in the first piece (12) to be connected and which is curved and thereby tightens the joint. 10 Method according to claim 1, characterized in that the finished dressing is secured by using a reading tray (4). Method according to claim 1, characterized in that the part (2) is bonded in place 15 by means of the head part (5) of the screw-like member (3) which supports against a shoulder (10) on the part (2). Method according to claim 1, characterized in that the part (2) is substantially flush with the surface of the piece to be joined. 20 Device for making a connection between two pieces by means of a screw (11) provided with a head (13) which is placed in the first piece (12) to be connected and a tapered cutter (2) provided with is placed in the second piece and secured with a screw-like member (3) to a drill heel, characterized in that the counterpart (2) also comprises a groove (7) for receiving the head (13) of the screw in the the first paragraph, wherein the cutter has a curved shape (7) T which spans the dressing. CC CL Apparatus according to claim 5, characterized in that it further comprises a reading tray (4). o CM Device according to claim 5, characterized in that the diameter of the screw (3) is substantially smaller than the diameter of the part (2). 5 Device according to any of the preceding claims 5-7, characterized in that the head (5) of the screw (3) is immersed in the shelf (10) of the part (2). CM δ CM sj- 0 O) cc CL δ o r ^ · o o CM