FR2469991A1 - SAWING INSTALLATION EQUIPPED WITH CHIPPELING TOOLS - Google Patents

Abstract

The shaft (4) is arranged above the work-transport plane (12). The running direction of the saw blades (5) leaving the cutting point (11), in their section lying below the shaft (4), coincides with the feed direction (7) of the workpiece (W). The workpiece (W) can rest on a counterpressure beam (9) in the area of a cutting line (10). The counterpressure beam (9) can be designed as a rotating counterpressure roller. The sawing apparatus serves to saw and cut wood into chips with a grain flow parallel to the surface.

Description

 The present invention relates to a sawing installation or mechanical saw equipped with a set of tools composed of circular saw blades and tools for chipping into chips mounted on a common axis.

In the sawing technique applied to the work and to the transfer of wood, various types of mechanical saws are known which carry on one axis the saw blades necessary for sawing the workpiece and the chip cutting tools used to reduce at the same time the irregular side of the piece in shavings or similar fragments of small dimensions. The disadvantage of these known saw-chip-cutting combination tools lies in the fact that the product detached from the irregular side of the workpiece does not have the characteristics of a material in the form of parings, the fibers of which extend parallel to the clipping surface.

The present invention provides a mechanical saw equipped with a set of tools making it possible to saw the pieces presented in lumber or in trays (rough sawn wood), and to obtain by means of tools for chipping into chips shavings the fibers of which extend parallel to the surface thereof
According to the present invention, the set of tools works the part according to the cutting mode by swallowing, that is to say that the axis carrying the saw blades and the tools for chipping into chips is located above. of the workpiece transport plane and that the direction of rotation of the saw blades leaving the cutting zone corresponds, without the region below the ase, to the direction of advance of the workpiece.

Other embodiments and advantageous characteristics of the invention are described below with the aid of an exemplary embodiment of a mechanical saw equipped with chipping tools, illustrated in the accompanying drawings, in which
- Figure 1 shows the mechanical saw in side view; and
- Figure 2 is a top view of the mechanical saw
The mechanical saw shown is used to produce, using saw blades 5 mounted at a certain axial distance from each other on a common shaft 4, of wood cut into strips, and to operate tools 6 for chipping into chips. mounted coaxially with the saw blades and which allow the irregular sides which the workpiece normally exhibits to be transformed into trimmings suitable for in use as cellulose and the fibers of which extend parallel to the surface.

 The construction of the power saw is described in detail below.

In a machine body 1 are incorporated several lower advance cylinders 2 mounted fixed and several upper advance cylinders 3 movable vertically.

The peripheral surfaces of the lower feed rollers 2 form a communal transport plane 2 for the workpieces W, one of which is hatched in FIG. 1, for clarity, in its terminal part shown in front of the entrance to the mechanical saw. Such a part is indicated in FIG. 2 by broken lines.

In the center of the machine body 1 is a tool-holding shaft 4 on which are wedged both the circular saw blades 5 and the chip-breaking tools 6. The tools 6 for chip-breaking form respectively the right end part and the left end part of this tool set. The parts W pass through the machine in the direction of advance indicated in 7, the direction of rotation 8 of the tools being that corresponding to the principle of cutting downstream. This means that the axis A of the saw blades 5 and the chip cutting tools is located above the work plane 12 and that the direction of rotation 8 of the saw blades leaving the cutting area corresponds , in the region below the axis, in the direction of advance 7 of the part W.

 In order to correctly absorb the chip breaking forces, there is provided immediately in front of the set of tools 4, 5, 6 a counter-pressure member presented in the form of a rotary or fixed counter-pressure bar 9. The counter-pressure member 9 extends over the entire width of the machine body 1 parallel to the axis of the shaft 4 and is packed in the immediate vicinity of the line of intersection 10 of the circle 13 described by all cutting members 14 of the chip breaking tools 6 and of the transport plane 12 of the parts This arrangement offers the advantage that the back pressure bar 9 can fulfill its function so as to support the part in the cutting area itself.

In the exemplary embodiment shown, the chip breaking tool 6 comprises multiple individual cutting members 14 extending approximately radially and spaces relative to each other each time with the same action interval 15 equal to the desired length of the trimmings, which corresponds to the length of the wood fibers extending parallel to the surface of the rotations obtained. This results in the advantage that the parings can during transport and subsequent processing, due to the favorable length of the fibers between 1 and 5 cm, be transported without comprising a significant proportion of unusable waste. By means of deflectors, these trimmings can easily be directed so as to remain separated from the sawdust produced by the circular saw blades 5.

Claims (6)

1. Sawing installation equipped with a set of tools made up of circular saw blades and chip breaking tools mounted on a common shaft, characterized in that the axis (A) of the saw blades (5) and tools (6) for chipping into pieces is located above the work plane (12) of the workpieces and in that the direction of rotation (8) of the saw blades leaving the cutting area (11) corresponds, in the region located below the axis, in the direction of advance (7) of the part (W) (principle of cutting downstream).  2. Sawing installation according to claim 1, characterized in that a counter-pressure member. in particular a back pressure bar (9), is located in the immediate vicinity of the line of intersection (10) of the envelope surface of the circular paths (13) of all the cutting members of the chipping tools (6, 14) on the one hand and the transport plan (12) of the parts, on the other hand. 3. Sawing installation according to claim 2, characterized in that the back-pressure member 9 is rotary or fixed. 4. Sawing installation according to claim 1, characterized in that a united backpressure bar or a rotary backpressure cylinder is located under the workpiece transport plane, immediately in front of the tool.  5. Sawing installation according to any one of claims 1 to 4, characterized in that the tools (6) for chipping into chips have several individual cutting members (14) which are spaced apart from one another by an interval action (15) which determines the length of the wood fibers extending parallel to the surface of the trimmings or shavings.  6. Sawing installation according to claim 5, characterized in that the action interval (15) of two usuccessive cutting edges (14) is about 1 to 5 cm.