FI94503C - Jig Saw - Google Patents

Description

PLUG BLADE '94503

The invention relates to a punch blade as defined in claim 1, with which a symmetrical notch is made in an elongate profile, strip or beam.

Rotary shaped blades are already known for milling notches in the wood industry for single pieces or for pieces arranged in several rows, whereby by carrying the blade over the pieces, the work can be done faster and productivity can increase. If a notch is required on one side of the piece, the pieces are turned over and the notch on the other side is milled. If no high demands are placed on the accuracy of the final result, the working method is relatively fast and usable and even accurate, because the shape blade just makes a notch in its size.

If it is important that the notches formed on each side of the profile are exactly correct with each other, the notch made with the shape blade several times and inverted sometimes will not give a sufficiently accurate result. Especially the distance between the notches may vary as well as there will be easy staggering between the notches.

The insertion blade according to the invention avoids these problems and the invention is characterized by what is stated in the claims.

The most important advantage of the invention is that the notches on both sides of the profile come in exactly the right position, shape and size, because the notches are made in one work step at the same time. Work done with a blade can be made fast and profitable for large series, and blade machining is also suitable for small series. It is important to achieve the accuracy that is necessary when making truss extensions to profiles. There must be almost no clearance or misalignment in the joint of the cross-linked strips and profiles, as these are easily visible outwards from the well-displayed gratings in the most visible places.

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When cross-slats become continuous, i.e. unbroken, an exact appearance, greater strength and faster assembly work is achieved compared to the known grid-making method, in which the slats of one direction are full-length and the slats of the other direction are pieces which are laid and glued as intermediate slats.

In the following, the invention will be explained in more detail with reference to the accompanying drawing, in which Figure 1 shows the blade in oblique view.

Figure 2 shows an end view of the blade.

Figure 3 shows the blade body in oblique view.

Figure 4 shows an end view of the blade body.

Figure 5 shows a notched wooden strip.

Figure 6 shows a notched wooden strip from the side.

Figure 7 shows a wooden lattice.

Figure 1 shows a stabbing blade consisting of two blade bodies 1 which are a blade material bent at an angle of 90 °. The blade bodies 1 are fastened to each other by means of a fastener 3 and at the same time also fastened to the blade shaft 2. The ends of the blade bodies 1 are sharpened into a chisel blade so that the sharpening chamfers are inside the blade opening at a 90 * angle. In addition, the blades are bevelled so that the outer tips of the blades are forward. The angle ä is between 30 ° and 60 * measured from the center of the blade axis. The blade is attached to a device that makes a 2-point movement from the shaft. An open gap is formed between the blade bodies 1, the length of which is at least the distance required by the gun movement.

Figure 2 shows how the blade bodies 1 are fastened to each other by means of screws by means of a fastener 3 and counter-pieces 4.

; The blade bodies 1 have free holes for tightening with screws between the parts 3 and 4.

Figure 3 shows a blade body 1, which shows the sharpening of the chisel blades so that the blade chamfers 5 are inside the corner of the blade body. It can also be seen from the figure that the blade part 6 is sharpened at the folding point of the blade body, the bevel of which is also inwards.

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Figure 4 shows an end view of the blade body 1, whereby the chamfers 5 and the blade portion 6 located between them form a continuous vibration C1 to C2. The blade bodies 1 are fastened to each other so that the points 10 on the cutting edges C1-C2 form an exact square 7. In this case, the opposite cutting edges C1 of the blades and C2 are also in the same plane.

Figure 5 shows a wooden profile strip 8 with a piece removed from each side of the center line of the strip with a stabbing blade according to the invention. The width d of the ridge and the base part of the strip 8 is arranged to be the same as the side length of the square 7 formed in the center of the blade. In this case, the blade cuts out a piece from the strip 8 which exceeds the width dimension d.

Figure 6 shows a side view of the list at the notch. When part B is removed from the second strip 8 and part A is removed from the second strip 9, the strips can be precisely superimposed crosswise according to Fig. 7 and an exact lattice connection is obtained. By making the notches 8.9 evenly with a tool according to the invention, inserting the notches and removing part A and part B from the other strips, precise wooden gratings are obtained.

It should be noted that the blade can be used to notch slats, regardless of their profile shape, and slats with the same profile can be installed as a grid. Most profiles must be provided with a notch during the notching process in order to avoid unnecessary splitting of the wood during plugging.

The blade can be formed of several separate chisel blades, which, however, makes the adjustment of the blade considerably more difficult. Moreover, it is not intended to limit the invention to the accompanying exemplary embodiment, but many modifications are possible within the scope of the inventive idea defined by the claims.

Claims (5)

A cutting blade for machining a mutually symmetrical pattern, in particular on each side of a wooden profile strip or beam, the cutting blade comprising chisel blades (5) extending outwards from the center of the blade shaft (2) at 45 °, the beveled surfaces arranged on the blade side of the profile (8) , that the chisel blades (5) start at a distance from the center line of the blade shaft (2) and that the opposite chisel blades are connected in pairs by a blade part (6) connecting their starting points (10). Insert according to Claim 1, characterized in that the insert consists of two pairs of chisels connected to each other, the pair of chisels comprising two outwardly directed chisel blades (5) in the same blade body (1) and a blade part (6) connecting their starting points (10). Insert blade according to Claims 1 and 2, characterized in that the outwardly directed chisel blades (5) are at the same time directed forward at an angle of 30 ° to 60 °. Insertion blade according to one of the preceding claims 1 to 3, characterized in that the initial chisel blades (5). . the points (10) form a square in the center of the blade. Insert blade according to one of the preceding claims 1 to 4, characterized in that a gap is formed between the opposite pairs of blades (1), the length of which is adapted to at least the working distance of the blade and which leaves an intact base (A, B) in the strip (8) to be machined. - 94503