SE514607C2 - Cutting link to saw chain - Google Patents

Abstract

Cutting link for a saw chain comprising an inner mainly flat link section (1) that is provided with two apertures (2) by means of which the cutting link is fixed to two adjoining links in the saw chain via axle journals, and a cutting member (3) that is arranged protruding from the flat link section (1). The cutting member (3) shows an upper section (3.1) that extends mainly perpendicular to the flat link section (1) and shows a cutter (3.2) at its front edge, and an open rear gavel (3.3) at its rear edge in the direction of motion of the saw chain. The rear gable (3.3) of the cutting member (3) inclines forward in the direction of motion of the saw chain at an angle of c2 = 50-80 DEG to the longitudinal direction (L) of the flat link section (1). The cutting member (3) shows a mainly U-shaped cross section, the opening betweens the shanks being directed sideways on the link section (1).

Description

lO 15 20 25 30 35 514 607 2 sawing, The main difference lies in whether a cutting link is intended for a cut in a direction along the fiber direction of the wood, which gives long chip-like chips, or for a cut across the fiber direction of the wood, i.e. a cleavage of the fibers in the fiber direction, giving short powder-like chips.

It has thereby been shown that a desired removal of chips from the cutting links, especially during a cutting, is of great importance in order to be able to increase the cutting speed, e.g. during a deforestation.

An improvement of the removal or evacuation of chips from the cutting links gives a clear reduction of the cutting time, i.e. an increasing production in deforestation.

A saw chain intended for a cut is described in the German patent specification DE-A1-2 254 647 and a saw chain intended for a cutting is described in the German patent specification DE 1 453 151.

In the case of cutting links of this kind, it is known to assign certain parts selected angular value: Thus it is meant that: angle "al" constitutes the inclination or impact angle of the cutting edge in a vertical plane (figure 1), angle "b" constitutes cutting angle shown in a horizontal plane (figure 3) , angle shown in a vertical plane (Figure 1), angle "dl" shown in a horizontal plane (Figure 3), "cl" is a common rear end angle is a common rear edge angle, angle "e" is a clearance angle shown in a vertical plane (Figure 1 ), the angle "f" is the clearance angle shown in a horizontal plane (Figure 3).

The prior art also includes the following patent publications; US-A-4,348,926 US-A-2,652,076 DE-A1-2 254 647 EP-A1-O 712 700; US-A-4,562,762 US-A-4,133,239 US-A-3,951,027 US-A-3,735,662 US-A-3,106,232 US-A-2,924,254 US-A-3,180, 378 US-A-3,261,385 US-A-4,348,926 US-A-4,535,667 US-A-2,515,55O WO-A1-83 / 01409 US-A-3,929,049 DE-A1-19 718 268 US-A-4,979,416 US -A-3,951, O27 US-A-2,652,076 and EP-A1-0 712 700.

Since the significant features of the present invention are mainly concentrated in the design of a rear end angle assigned to the link, which should be adapted within selected angular values, the following patent publications may be of particular interest.

Therefore, various factors are taken into account, such as the rear end angle, the cutting angle and the trailing edge angle, as well as a length relationship between the borders, denoted A; B in Figure 3, and the prior art can be stated that; US-A-2,652,076 This construction indicates a slight rear end angle, approximately slightly less than a right angle, otherwise a leg-like outer surface (100) is shaped like a rectangle, which means that the trailing edge angle borders on 90 °.

EP-A1-0 712 700 This construction has a rear end angle of over 90 °, say 98 ° and a rear edge angle of 65 °.

However, a trapezoidal shape of the surface (40a) is shown here with a ratio between the lengths of the side portions or the side lines (A; B) 3: 4.8 = 0.7.

US-A-4,562,762 This construction shows a cutting link where the rear end angle is selected with a value of about 82 ° and with a surface (20) with the rear edge angle slightly less than 90 °. The ratio of the lengths of the side portions (A: B) 2.0: 3 = 0.7.

US-A-4,113,239 Shown here is a ratio where the rear end angle is selected slightly below 80 ° (78 °) and with the ratio between the lengths of the side portions (A: B) 2.0: 2.5 = 0.8 . The rear edge angle is here selected to 90 °.

US-A-3,951,027 is shown here on a saw link where the rear edge angle is selected to slightly above 90 ° while the rear end angle is selected to 90 °. The length ratio (A: B) 1.6: 2.7 = 0.6.

US-A-3,106,232 is shown here on a saw link where the rear end angle and the rear edge angle are selected to 90 ° and the length ratio (A: B) 1.4: 1.9 = 0.74.

US-A-2,924,254 Shown here is a saw link where the rear end angle is selected to slightly below 80 °, the rear edge angle is selected to 90 ° and the length ratio (A: B) is 1.0: 1.3 = 0.77. 10 15 20 25 30 35 514 607 5 US-A-3,261,385 A saw link is shown here where the rear end angle and the rear edge angle are selected to 90 °. The length ratio (A: B) 2.0: 2.8 = 0.72.

WO-A1-83 / 01409 A saw link is shown here where the rear end angle and the rear edge angle are selected to 90 ° and with the ratio (A: B) 2.0: 2.2 = 0.9.

US-A-3,929,049 is shown here on a saw link where the rear end angle can be considered to be selected to 82 ° by measurements in the figure, possibly 80, the rear edge angle is selected to 75 °. The ratio (A: B) 5:10 = 0.5.

US-A-2,515,550 shown here on a saw link where the rear end angle is about 60 ° while the rear edge angle is selected to 90 °. The length ratio (A: B), 1.0: 1.4 = 0.3.

DESCRIPTION_B! _ Fl EEEINMIN§EHi A clear improvement in the removal of chips from cutting links has been achieved with a cutting link which, like known cutting links, comprises an inner planar link part or section provided with two holes, with which the cutting link becomes attachable to two giving or adjacent links in the saw chain via shaft pins, so that a cutting member is arranged projecting from the said link part or section.

The cutting member comprises an upper part, which extends substantially perpendicularly to the flat link part and has a cutting edge at its front edge and an open rear end at its rear edge in relation to the direction of movement of the saw chain. The new and characteristic feature of the present invention is that the rear end of the cutting member slopes forward in the direction of movement of the saw chain a selected angle C2 = 50-80 ° towards the longitudinal direction of the flat link part.

Preferably, the rear end of the cutting member is inclined at an angle C2 = 50 ° to the longitudinal direction of the link part. In a preferred but non-limiting embodiment of the invention, the cutting member also has a substantially U-shaped cross-section where the opening between the legs is directed to the side relative to the link part.

Further changes to the geometry of the cutting link, which also enable a higher sawing speed, appear from the more specified description with a reference to the attached figure sheet.

Due to the changed geometry, a faster sawing is obtained at otherwise equal sawing conditions, but also a sharp reduction of cracks in the end wood when cutting tree trunks, which also contributes to increasing the economic yield at e.g. deforestation.

Further details and features relating to the present invention appear from the description of the figure sheet and the claims. The advantages which can mainly be considered to be characteristic of a cutting link indicated in accordance with the present invention are that in this way conditions have been created for improving the chip departure from the cutting link and thereby being able to increase the cutting speed.

What can primarily be considered to be characteristic of a cutting link indicated in accordance with the present invention is stated in the characterizing part of the appended claim 1.

A presently proposed embodiment, having the significant features associated with the present invention, will now be described in more detail with reference to the accompanying drawing, in which; Figure 1 shows a cutting link in a vertical plane seen from one side, Figure 2 shows one end surface of the cutting link according to figure 1 seen from the right and Figure 3 shows the cutting link in a horizontal plane and according to figure 1 seen from above.

The cutting link "S", shown in the figures, comprises a flat link part or section 1, which is provided with two holes 2, 2 ', with which the cutting link "S" is attachable to two surrounding or adjacent drive links in the saw chain by means of riveted studs, not shown in the figures.

A counter-link is attached to the opposite side of the drive links on the same shaft journals.

The drive links have drive means directed inwards towards a drive wheel, while the respective cutting link has a cutting member 3 directed outwards from the saw chain.

A guide tooth 4 or a cutting depth limiter projects into the plane of the link part 1 with its tip 4 'located in front of the cutting member 3 and its cutting edge 3.2.

The cutting member 3 has a substantially U-shaped cross section, where an opening 3.4 between legs 3.1; 3.5; 3.6 facing one side in relation to the flat link part 1 and the plane through a saw bar along which the saw chain runs.

The outer or upper leg 3.1 of the cutting member 3 extends thereby in a plane perpendicular to the flat link part or sector 1. In addition, the cutting member 3 has a cutting edge 3.2, at its front edge in the direction of movement of the saw chain. , and a rear end 3.3, at its rear edge in the said direction of movement.

In Figures 1 and 3, the contours of well-known cutting links are drawn in dotted lines, while a cutting link according to the invention is drawn with solid lines.

The longitudinal direction of the cutting link is marked L in Figure 1 and a longitudinally oriented parallel parallel to the longitudinal direction, the holes 2,2 'are assigned, the center line is indicated by the reference numeral L' in Figures 1 and 3.

Figure 1 illustrates that a saw blade is intended to be in a vertical plane below the cutting link "S".

The cutting edge 3.2 has on well-known links a vertical slope a1 = 85 °, but according to the invention the slope "a2" should be 70-85 °, preferably "a2" = 78 ° towards a horizontal plane through the longitudinal center line L '.

The cutting edge 3.2 has along the leg 3.1 the same inclination b = 60 ° in the horizontal plane, according to figure 3, towards a vertical plane of the longitudinal center line L 'at both known links and that according to the invention, but can vary.

The rear end 3.3 of the cutting member 3 has on some known links a slope c1 of 87 ° - 90 ° but according to the invention a slope "c2" of 50 - 80 ° is proposed, "c2" = 50 ° towards a horizontal plane through the longitudinal center line L '. preferably the rear end 3.3 of the cutting member 3 has along the leg 3.1 on certain known links a slope d1 of 90 ° but according to the invention the slope "d2" should be 70 - 90 °, preferably "d2" 10 15 20 25 30 35 514 607 _ 9 _ = 70 ° in the vertical plane towards the horizontal plane through the longitudinal center line L '.

The upper or outer leg 3.1 of the cutting member 3 slopes backwards from the cutting edge 3.2 with an approximate clearance angle "e" of 5 "according to the invention, but can also vary.

The bottom portion 3.5 of the cutting member 3, between the legs 3.1 and 3.6, is inclined backwards in the horizontal plane from the cutting edge 3.2 relative to the flat link part 1 with an approximate clearance angle "f" of 4 ° according to the invention but can also vary.

The open rear end 3.3 of the cutting member 3 is created naturally when the cutting member 3 has a U-shaped cross section, which is also known from existing cutting links.

The surprising increase in the sawing speed made possible by the present invention seems to lie in the fact that the cutting member 3.2 on the cutting link "S" has a relatively shorter outer cutting link 3.1, viewed in the direction of movement of the sawing chain, which results in a reduced braking of the chip shall pass between the legs of the cutting member 3.5; 3.6. The chip departure from the cutting member 3 is thereby facilitated.

It is per se conceivable to have the outer leg 3.1 designed shorter and to have a straight rear end 3.3 with otherwise unchanged dimensions on the cutting link and to achieve this increase in the sawing speed.

However, this possibility is limited by the strength of the material in the cutting link "S" as its base becomes too short and may rupture, which is why an inclined or a concavely rounded rear end 3.3 according to the invention is preferred.

To further improve the sawing result, the current round grinding of the insert 3.2 can be replaced with a hexagonal or 514 514 607 octagonal grinding.

Supplementary values for a clarification of certain parts of the basic documents.

Considering now the present invention, in the light of the prior art, and considering the intention of the construction indicated and dimensioned in the drawings, to be able to offer an arrangement with a distinct ambition to be able to improve the chip output when cutting wood material and thereby improve a transport or evacuation of chip chips from the cutting links and reduce the cracking of the end wood when cutting the tree trunk, special consideration must be given to the impact and the degree of impact from at least the following factors: a. The chip thickness, which is determined by a selected stand between the tip (4 ') of a cutting depth limiter (4') and the horizontal and inclined cutting surface of the cutting edge 3.2. b. Selected angular value (C2 = 50 - 80 °, above 50 °) for a rear end angle. most suitable slightly c. Selected angular value (a2 = 70 - 85 °, most suitable around 78 °) for an impact angle. d. Selected angular value (b = 60 °) for a cutting angle. e. Selected angular value (d2 = 70 - 90 °, most preferably around 70 °) for a trailing edge angle. f. Selected length (13) for a free edge. the cutting surface and its adjacent corners, g. The ratio (A: B) between cutting edges belonging to the cutting members and the shape of the free leg. 10 15 20 25 30 35 514 607 _ 11 _ The reason why these factors are likely to be so significant and in a chosen combination become so critical, in order to be able to achieve the desired technical effects, is that it is particularly difficult to predict the changes that will occur. be related to the chip formation and chip movement during the cutting sequence for a selected change in the above factors.

However, it can be reasonably assumed that a cutting chip or chipboard, in a cutting sequence, develops from a cutting edge surface and is pressed by the thickness of the cutting steel downwards below the flat cutting member part (3: 1) while being rotated and angled by a produced edge surface into it. U-shaped part (3.4) and to an abutment against the inner surfaces.

When the edge surface of the cutting surface finishes the cutting chip, a "rolling up" of the cutting chip takes place within a rearwardly tapering space and the invention is based on this rolling distance being selected shortly before the chip leaves the cutting link.

The invention is of course not limited to the embodiment given above as an example, but may undergo modifications within the scope of the inventive concept illustrated in the following claims.

Claims (11)

10 15 20 25 30 35 514 607 _12- An cutting saw link belonging to an endless saw chain comprising in one unit; a guide, preferably flat, section (1), provided with two holes (2,2 '), adapted to be able to rotatably cooperate with adjacent saw chain-associated links via hole-adapted shaft pins, a cutting depth limiter (4) connected to said section (1). ), and a laterally extending cutting member (3) extending from said section (1), which is assigned a substantially U-shaped cross-section, one leg (3.6) adjoining said section (1) and the other leg ( 3.l) carries a leading cutting edge or edge (3.2) viewed in the direction of movement of the cutting link "S" and with a cutting surface oriented through at least said second leg to form an inclined rear end, characterized therefrom, (3.l). ) and a leg connecting portion (3.5) that a selected angular value for an angle assigned to a rear end (C2) is adapted to between 50 and 80 °, preferably slightly above 50 °, in order to facilitate a chip formation and chip movement generated by a cutting process. Cutting link according to Claim 1, characterized in that a selected angular value for an angle (d2) assigned to a trailing edge is adapted to between 70 and 90 °, preferably slightly above 70 °. Cutting link according to Claim 1 or 2, characterized in that a selected angular value for an impact angle (α2) is adapted to 70 to 85 °, preferably 78 °. Cutting link according to one of the preceding claims, characterized in that a selected angular value for a cutting angle (b) is adapted to 60 °. 10 15 20 25 30 35 514 607 _13- Cutting link according to one of the preceding claims, characterized in that the inclined rear end is oriented to extend beyond the two legs of the cutting member (3.1; 3.6). Cutting link according to claim 1, characterized in that said second leg has a flat upper surface substantially adjoining a parallel staircase. Cutting link according to Claim 1, characterized in that a cutting angle (b) is assigned an angular value which lies within the selected limit values for a trailing edge angle (d2). Cutting link according to Claim 1, characterized in that a cutting angle (b) is assigned an angular value which lies within the selected limit values for a rear end angle (C2). Cutting link according to claim 1, characterized in that a ratio between the lengths of spaced edge surfaces of said second leg (3.1) is selected to 2/3. Cutting link according to Claim 1, characterized in that the second leg (3.1) is adapted to tilt backwards with a clearance angle of 5 °. Cutting link according to Claim 1, characterized in that the cutting edge of the cutting member is assigned a polygonal grinding.