RU2146609C1 - Milling head for processing thin wood into squared beam and commercial chips or shavings - Google Patents

Abstract

FIELD: woodworking machinery and equipment. SUBSTANCE: milling head relates to milling-type wood cutting tools. Milling head has milling cutter in the form of central bush or hub with blades. Ends of blades are inclined with respect to axle of rotation and are provided with strip-like knives. Hub is also provided with second similar milling cutter which is mounted coaxially and oppositely to first milling cutter. Second milling cutter is fixed from displacement relative to first milling cutter. Second milling cutter can be displaced in plane of rotation. Sharp edges of blade knives are positioned in diametrical planes. EFFECT: higher efficiency. 3 dwg

Description

 The invention relates to the woodworking industry, and specifically relates to the improvement of tools and equipment used for processing fine wood (tops and knots of trees) into four-edged bars with simultaneous grinding of removable peripheral parts of the wood.

 A known method of processing fine wood and a device for its implementation according to patent applications of Japan: N 56-56801, 56-56802, 56-56803 and 56-56804, class. MKI B 27 B 5/02, publication 05.19.81. These inventions can be used to obtain square squared timber from fine wood and are characterized in that they are cut using four circular saw heads divided into two pairs. In each pair, the heads have a common axis of rotation and can move along the axis of rotation, which allows you to adjust the distance between them depending on the diameter of the processed tonometer. Each circular saw blade contains several circular saw blades separated by gaskets. The ends of the gaskets are made curved, as a result of which the circular saws are deformed so that their cutting edges are located along a helical line.

 The disadvantage of these inventions is that the removed peripheral part of the wood is crushed into sawdust (by the teeth of circular saws), the further use of which is associated with technological difficulties, and their industrial use is limited. From an economic point of view, it is more expedient to chop the removed peripheral part of wood either into technological chips - the feedstock of the pulp and paper industry, or into wood-shavings of plate form used in the manufacture of chipboards.

 For longitudinal processing of logs of medium and large diameters, the so-called aggregate technology has been widely used, in which a step beam is formed from the log before its longitudinal sawing, and step milling heads with arc cutters are used to obtain its upper and lower curly faces (as an example of construction heads of this type, see the description of the invention according to the USSR author's certificate, N 1355491, class MKI B 27 G 13/00, publication 11/30/87), and the lateral flat edges of the beam are formed, as a rule, m use cutters in the form of a truncated cone with a circular saw fixed on a small base (see, for example, the prospectus of the Swedish company Alstrem for the milling and sawing machine PH 700). A similar technology is used by Wema Probst, Germany, for processing into edged sawn timber and wood chips and fine logs with a diameter of 12-14 cm. The disadvantages of aggregate processing technology is, firstly, that its use is economically justified only for timber with a cross section 12 cm and above. The tops and large knots of trees with a diameter of 6 - 10 cm, the amount of which is up to 20% of the volume of harvested wood, are still either burned directly in the cutting area, or, in the best case, are crushed into technological wood chips on mobile chippers. Secondly, the milling heads used in the aggregate processing of logs are equipped with either arc or special profile cutters, which are laborious to manufacture and require specialized equipment for their regrinding. Thirdly, all the above-mentioned designs of milling heads are intended for grinding the removed peripheral part of the wood only into technological chips. For the readjustment of mills to obtain wood chips, a radical change in their design is necessary.

 These disadvantages are partially eliminated by using the tool used in the construction of the Ts2D-1F model milling and cutting machine for grinding the peripheral part of the wood. The milling heads of this machine are a central hub with blades, the ends of which are bent and located at an angle to the axis of rotation. On the bent ends of the blades fixed plate knives. By varying the number of blades and the rotational speed of the cutter (ultimately the feed rate to the knife), the peripheral part of the sawn cut on the machine can be chopped at will either in technological chips or in wood chips for the production of chipboards. By technical nature, the milling head of the machine Ts2D-1F is the closest to the claimed and can be adopted as a prototype.

 The disadvantage of this, as in all the milling heads described above, is that each of them forms only one (flat or step) face of the beam during operation.

 The aim of the invention is to eliminate the aforementioned disadvantage of known structures, ensuring the simultaneous milling of two adjacent, angled to each other, faces of the beam when basing it on opposite ribs, placing them in a vertical plane.

 This goal is achieved by the fact that the milling head, including a milling cutter in the form of a central sleeve with blades, the ends of which are inclined to the axis of rotation and equipped with plate knives, is equipped with a second similar milling cutter installed opposite and coaxial with the first fixing them relative to each other and offset in the plane of rotation while the blades of the knives of both cutters are located in diametrical planes.

 Below, as an example of a practical implementation of the invention, a detailed description of the construction and principle of operation of the inventive milling head, explained by the drawings, is given. In FIG. 1 shows its general view (frontal view), in FIG. 2 is a side view of the milling head, in FIG. Figure 3 shows a simplified kinematic diagram of the machine on which round wood billets are processed into four-edged timber.

The milling head includes coaxially and opposite to each other mounted mills 1 and 2. Each milling cutter includes a central hub hub 3 and blades 4, the ends 5 of which are located at an angle α to the axis of rotation 6 of the head. At the bent ends 5 of the cutters, by means of pressure plates 7 and adjusting screws (not shown), plate-shaped cutters 8 are fixed, while the blade 9 of the cutters are located in the diametrical planes 10 of the cutters. The machine (Fig. 3), on which the invention is used, contains two inventive heads - the upper Ф _в and lower Ф _н and the groups of centering rollers 11 and 12, located on the top and bottom of the workpiece Z _g , the feed direction of which is shown by an arrow.

When feeding the workpiece, the cutter F _n is first included in the work. Due to the opposite arrangement of cutters 1 and 2, milling of the lower adjacent faces of the beam Г _{н is} performed simultaneously. Due to the saddle centering rollers during further feeding of the workpiece, it is reliably fixed when the milling head Ф _{в is} turned _on . By changing the number of cutters in cutters 1 and 2, the peripheral removable part of the wood can be crushed either into technological chips or into shavings.

 The milling heads of the claimed design are made in metal and tested under production conditions. The test results confirmed all of their advantages mentioned above.

Claims (1)

 A milling head for processing fine wood into a timber and technological wood chips or shavings, including a milling cutter in the form of a central sleeve with blades, the ends of which are inclined to the axis of rotation and provided with plate cutters, characterized in that it is equipped with a second similar milling cutter installed opposite and coaxial with the first with fixing them relative to each other and offset in the plane of rotation, while the blades of the knives of both mills are located in their diametrical planes.

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