CA1242373A

CA1242373A - Radial saw with toothed peripheral hoop

Info

Publication number: CA1242373A
Application number: CA000543168A
Authority: CA
Inventors: Victorin Royer
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-07-28
Filing date: 1987-07-28
Publication date: 1988-09-27

Abstract

Une scie circulaire comportant une plaque centrale mince à grand diamètre et un cerceau monté solidaire à la périphérie de la plaque. Le cerceau a une épaisseur, dans le sens radial, très inférieure au diamètre de la plaque; cette épaisseur et la largeur du cerceau dans le sens transversal excédant largement l'épaisseur de la plaque centrale. Les dimensions relatives précitées sont choisies de façon à augmenter substantiellement la force d'inertie de la scie lors du sciage d'une pièce. La périphérie externe du cerceau est divisée en secteurs dentaires dont chacun comporte une aire de dégagement de copeaux se déployant dans le sens radial; un bord externe dont une partie forme une découpé ouvrant, à une extrémité, sur l'aire de dégagement et formant une saillie d'arrêt à l'autre extrémité; une dent de sciage logée dans la découpe en s'appuyant, à un bout, contre la saillie d'arrêt et étant biseautée à l'autre bout, pour former une arête tranchante. Ce bout biseauté surplombe l'aire de dégagement. Enfin, la dent est fixée solidement mais de façon amovible dans la découpe.A circular saw comprising a thin central plate with large diameter and a hoop mounted integral at the periphery of the plate. The hoop has a thickness, in the radial direction, much less than the diameter of the plate; this thickness and the width of the hoop in the transverse direction greatly exceeding the thickness of the central plate. The aforementioned relative dimensions are chosen so as to substantially increase the inertia force of the saw when sawing a workpiece. The outer periphery of the hoop is divided into dental sectors, each of which has a space for the removal of chips extending in the radial direction; an outer edge, part of which forms a cutout opening, at one end, onto the clearance area and forming a stop projection at the other end; a sawtooth housed in the cutout pressing, at one end, against the stop projection and being bevelled at the other end, to form a sharp edge. This beveled end overlooks the clearance area. Finally, the tooth is fixed securely but removably in the cutout.

Description

La présente invention concerne diverses ameliorations aux scies circulaires utilisees, en parti-culier mais non exclusivement, dans l'industrie forestiere pour la coupe des arbres~
Les scies qui sont actuellement utilisés sont généralement minces par rapport à leur diamètre. Pour cette raison, elles gauchissent facilement et doivent être remplacées ou réparées à grand coût. En raison egalement de leur faible epaisseur, les dents de sciage qui débordent du plan de la scie,-alternative-ment de chaque cote, sont facilement endommagees ou écrasées et doivent être souvent aff~tées ou remplacees, si elles sont amovibles. Leur faible poids leur donne peu d'inertie de sorte qu'elles peuvent bloquer facile-ment.
La presente invention propose de corriger ces difficuItes en fixant,-autour d'un disque ou d'une plaque centrale mince, un cerceau dont l'épaisseur dans le sens radial est tres inferieure au diametre de la plaque, cette epaisseur de même que la largeur du cerceau dans le sens transversal excédant largement l'épaisseur de la plaque centrale. Les dimensions relatives precitees sont choi-sies de facon a augmenter appreciablement la force d'i-nertie, et donc la force de sciage, tout en protegeant la plaque centrale lors du sciage d'une piece de bois, tel un arbre, en raison de la grande largeur relative de l'arceau. Les dents de sciage, quant a elles, sont montees directement a la périphérie e~terne du cerceau.
Relativement au diamètre total de la scie, l'arceau est etroit et ses faces latérales préferablement polies et donc lisses, ce qui a pour effet de reduire considerablement le blocage de la scie resultant de la friction entre ses faces laterales et les faces opposees du trait de scie. Seules les pointes des dents, selon une reaIisation particulière de l'invention, debordent de chaque côte de l'arceau ce qui toutefois n'augmente '73 pratiquemen-t pas la surface coincee dans le trait de scie.
Le cerceau etant lisse et etroit, il glisse plus facilement dans le trait de scie et ce dernier est alors plus uniforme.
On comprendra facilement aussi que la présence de cet anneau augmente considerablement la resistance de la scie au gauchissement.
En bref, on.verra d'après la description qui suit que le cerceau.épais et fort protège la plaque ou disque central de m~me que les dents contre la com-pression, la deformation, le cisaillement et l'ecrasement~
Une description de realisations preferentielles de l'invention suit, faisant reference au dessin annexe où:
La Fig. 1 est une.vue en plan d'une scie cir-cula.ire selon une premiere realisation de l'invention alors que la Fig. 2 est une vue frontale, partiellement en coupe, e-t la Fig. 3 une.vue partielle, en perspective;
La Fig. 4 est une vue en eclate d'une seconde realisation; la Fig. 5 en-etant une.vue en coupe radiale partielle et la Fig. 6 une.vue frontale partielle.
Dans la première realisation, illustree par les Figs. 1, 2 et 3, la scie comporte un disque ou plaque central 1 conventionnel ayant, en.son centre,. un moyeu 3 de montage sur l'arbre d'un moteur d'antralnement. Cette plaque peut avoir une epaisseur de l'ordre de S/8" alors que son diametre est d'environ 50" .
Un cerceau lourd 5 de raidissement est monte solidaire, par soudure ou boulonnage, de la plaque cen-trale l, à sa peripherie 7. Ce cerceau,-rectangulaire ou carre en coupe, a une epaisseur 9 e~ une largeur 11 qui excèdent largement l.'epaisseur 13 de la plaque ce qui~
en consequence, augmente substantiellement la force d'inertie de la scie et en même temps protège la plaque The present invention relates to various improvements to the circular saws used, in particular culier but not exclusively, in industry for cutting trees ~
The saws that are currently in use are generally thin compared to their diameter. For this reason, they warp easily and must be replaced or repaired at great cost. In also because of their thinness, the teeth sawn overhanging the plane of the saw, -alternative-on each side, are easily damaged or overwritten and must be often sharpened or replaced, if they are removable. Their low weight gives them little inertia so they can block easy-is lying.
The present invention proposes to correct these difficulties in fixing, around a disc or a central plate thin, a hoop whose thickness in the radial direction is much smaller than the diameter of the plate, this thickness as well as the width of the hoop in the direction transverse greatly exceeding the thickness of the plate central. The aforementioned relative dimensions are chosen so as to appreciably increase the strength of inertia, and therefore the sawing force, while protecting the central plate when sawing a piece of wood, like a tree, because of the large relative width of the roll bar. The saw teeth are mounted directly on the periphery of the hoop.
Relative to the total diameter of the saw, the arch is narrow and its side faces preferably polished and therefore smooth, which has the effect of reducing considerably blocking the saw resulting from friction between its lateral faces and the opposite faces of the saw cut. Only the tips of the teeth, according to a particular realization of the invention, spill over on each side of the hoop which does not increase '73 practically not the surface stuck in the line of saw.
The hoop being smooth and narrow, it slides more easily in the saw cut and the latter is then more uniform.
We will also easily understand that the presence of this ring considerably increases the resistance of the warp saw.
In short, we will see from the description which follows that the thick and strong hoop protects the plate or central disc as well as the teeth against the pressure, deformation, shear and crushing ~
A description of preferential achievements of the invention follows, referring to the accompanying drawing or:
Fig. 1 is a plan view of a circular saw cula.ire according to a first embodiment of the invention while Fig. 2 is a front view, partially in section, and FIG. 3 a partial view, in perspective;
Fig. 4 is an exploded view of one second production; Fig. 5 by being a radial section view.
partial and Fig. 6 a partial frontal view.
In the first realization, illustrated by Figs. 1, 2 and 3, the saw has a disc or plate central 1 conventional having, en.son center ,. a hub 3 mounting on the shaft of an anti-rotation motor. This plate can have a thickness of the order of S / 8 "then that its diameter is about 50 ".
A heavy stiffening hoop 5 is mounted secured, by welding or bolting, to the central plate trale l, at its periphery 7. This hoop, -rectangular or square in section, at a thickness 9 e ~ a width 11 which greatly exceed the thickness 13 of the plate which ~
as a result, substantially increases the strength of inertia of the saw and at the same time protects the plate

- 2 -37~

centrale durant le sc:iage. A titre d'exemple seulement, le cerceau 5 peu-t etre de section ca~é avec des cotés de 2", ce qui signifie que le diamètre de la plaque centrale est 25 fois plus long que l'epaisseur 9 du cerceau.5. Il en va de meme pour la largeur 11. D'autre part,l'epaisseur 9 de l'arceau 5, étant de 2", est environ 3 ~ois celle de la plague 1.
La peripherie externe 15 du cerceau 5 est divisee en secteurs dentaires 17, egaux, dont chacun comporte une aire 19 de degagement de copeaux de bois qui. se deploie dans le sens radial; un bord externe 21 dont une partie forme une decoupe 23.ouvrant, à une extremitet sur l'aire 19 et formant une saillie d'arret 25, à l'autre extremite et, enfin, une dent de sciage 27 logee dans la decoupe 23, prenant appui à.un bout contre la saillie d'arret 25 et etant bisautée en 29 a l'autre - bout pour former une arete tranchante 31. Le bout biseaute surplombe l'aire 19, comme on peut le voir sur la Fig. 1.
La dent 27 est fixee, de facon amovible, dans son logement 23 par tout moyen convenable, tel les vis 33.
Comme le montrent les Figs. 2 et 3, chaque dent 27 a la forme d'un trapèze isocele dont la petite base s'appuie sur la saillie d'arrêt 25 et a la même largeur que la largeur du cerceau 5 et dont la grande base est constituee par l'arete tranchante 31. Cette derniere est concave en direction de la petite ~ase;
:~ elle et les cotes 35 du trapèze se rencontrent pour former des angles aigus debordant de chaque côte du cerceau 5.
Referant a.la Fig. 1, on note que la partie du bord e~terne 21 du cerceau 5, en amont de la dent 27, e-t la surface externe de la dent, dans chaque secteur dentaire 17, sont à peu pres coplanalres et sont inclinees, .

7~

en direction du centre de la plaque 1 et en s'éloignant de l'arête tranchante 31, d'un angle ~ d'environ 5.
On a ainsi des dents de sciage 27 qui, ferme-ment vissees ou boulonnees aux cerceaux 5 et s'appuyant solidement sur les saillies d'arret 25, peuvent fort adequatement resister aux forces tangenti.elles s'appli-quant sur les biseaux 29 durant le scia~e. De plus, les pointes formees aux int.ersections des arêtes coupantes 31 et des cotes 35 des dents 27 sont fortement intégrées au corps solide des dents 27 et peuvent ainsi mieux resister à l'ecrasement. Les dents sont de plus amovi-bles ce qui est fort utile si elles doivent etre affutees ou remplacees. Enfin, les pointes precitees en faisant saillie des faces laterales du'cerceau 5, produisent un trait de scie un peu'plus large que la largeur 11 du cer-ceau. Elle reduisent d'autant la ~riction dans la piece a scier et ainsi la possibilite de blocage de la scie dans son trait.
Dans la realisation des Figs. 4, 5 et 6, les dents de sciage 27' sont des plaques rectangulaires dont la largeur est la meme que celle-de l'arceau 5l. Deux couteaux circulaires 37, essentiellement plats, sont fixes au moyen de vis 38', chacun sur un des cotes du , cerceau. Ils ont un perimètre externe qui depasse radialement la face externe des dents 27' et sont biseautes, en 39, en direction des dents 27' comme le montre la Fig. 5.
Chacun des couteaux circulaires 37 repose sur une saillie 41 solidaire de l'arceau 5', sa face laterale externe etant coplanaire avec celle du couteau 37 qui lui correspond. On notera, sur la Fig. 5, que les faces laterales des couteaux 37 et des saillies 41 sont inclinees en direction du centre de la plaque cen-trale 1, pour reduire la friction dans le trait de scie.

Enfin, l'arete transchante 31' des dents de sciage 27' peuvent etre droites, comme illustré, ou arquées comme dans le cas des dents 27 de la première réalisation.
Il est avantageux de polir les faces latérales de l'arceau 5, 5', de meme que les faces latérales des couteaux circulaires 37 et saillies 51 pour réduire toute friction le plus possible.
On utilisera évidemment l'acier de qualité
habituelle pour toutes les composantes de la scie.
La scie selon l'invention telle que précédemment décrite a une rapidité de coupe beaucoup plus grande que les scies actuelles, ceci étant du à la forme de la dent qui est tranchante sur tous les côtés gui touchent l'arbre lors de la coupe et lui donnant ainsi l'avantage d'éviter le fendillement de l'arbre, chose qui se produit fréquemment avec les autres scies.
Deuxièmement, étant donné sa très grande inertie, elle peut opérer à une vitesse de rotation beaucoup plus réduite que celle des scie actuelles. En pratique 700 à ~00 tours/minute suffi amplement pour assurer une coupe parfaite de l,arbre alors que les scies actuelles doivent tourner à
une vitesse de 1 200 à 1 500 tours/minute sans quoi elles se bloquen-t frequemment dans l'arbre. Il est à noter que tous les ingénieurs dans le domaine déconseillent fortement de fabriquer des têtes de bûcheuses opérant à plus de 800 tours/minute car une vitesse accrue de la scie augmente considérablement le danger de bris mécaniques comme par exemple des morceaux de métal qui peuvent se détacher en raison de la trop grande vitesse augmentant ainsi le risque d'accidents pour les utilisateurs. Avec la scie à cerceau périphérique selon l'invention, il est dorénavant possible de réduire la vi-tesse et tous les risques que cela comporte.
Troisièmement, en raison de la coupe très nette et lisse qu'elle fait, la scie selon l'invention a l'avantage - 2 -37 ~

central during sawing. As an example only, the hoop 5 can be of section ca ~ é with sides of 2 ", which means that the diameter of the central plate is 25 times longer than the hoop thickness 9. 5. So does even for width 11. On the other hand, the thickness 9 of the arch 5, being 2 ", is approximately 3 ~ that of the plague 1.
The outer periphery 15 of the hoop 5 is divided into dental sectors 17, equal, each of which has an area 19 for clearing wood chips who. deploys in the radial direction; an outer edge 21 a part of which forms a cutout 23 opening, to a extremitet on area 19 and forming a stop projection 25, at the other end and, finally, a sawtooth 27 housed in the cutout 23, bearing on one end against the stop projection 25 and being bevelled at 29 to the other - tip to form a sharp edge 31. The tip bevel overlooks area 19, as you can see on Fig. 1.
Tooth 27 is removably fixed in its housing 23 by any suitable means, such as screw 33.
As shown in Figs. 2 and 3, each tooth 27 has the shape of an isosceles trapezium whose small base rests on stop projection 25 and has the same width than the width of the hoop 5 and whose large base is formed by the sharp edge 31. This the latter is concave in the direction of the small ~ ase;
: ~ it and the dimensions 35 of the trapezium meet for form acute angles overhanging each side of the hoop 5.
Referring to Fig. 1, we note that the part the edge e ~ dull 21 of the hoop 5, upstream of the tooth 27, and the external surface of the tooth, in each sector dental 17, are roughly flat and inclined, .

7 ~

towards the center of plate 1 and away of the cutting edge 31, of an angle ~ of approximately 5.
There are thus saw teeth 27 which, screwed or bolted to the hoops 5 and leaning securely on the stop projections 25, can strong adequately resist the tangential forces.
as for the bevels 29 during sawing. Moreover, the points formed at the intersections of the cutting edges 31 and dimensions 35 of the teeth 27 are strongly integrated to the solid body of teeth 27 and can thus better resist crushing. The teeth are also removable which is very useful if they need to be sharpened or replaced. Finally, the aforementioned points by making projection of the lateral faces of the hoop 5, produce a saw line slightly wider than the width 11 of the circle ceau. They reduce all the ~ riction in the workpiece and thus the possibility of locking the saw in its line.
In the realization of Figs. 4, 5 and 6, the saw teeth 27 'are rectangular plates of which the width is the same as that of the arch 5l. Of them circular knives 37, essentially flat, are fixed by means of 38 'screws, each on one of the dimensions of the , hoop. They have an external perimeter that exceeds radially the external face of the teeth 27 'and are bevelled, in 39, towards the teeth 27 'like the shows fig. 5.
Each of the circular knives 37 rests on a projection 41 integral with the arch 5 ′, its face lateral lateral being coplanar with that of the knife 37 which corresponds to it. It will be noted, in FIG. 5, that the side faces of the knives 37 and the projections 41 are tilted towards the center of the center plate trale 1, to reduce friction in the saw cut.

Finally, the cutting edge 31 'of the saw teeth 27 'can be straight, as illustrated, or arched as in the case of the teeth 27 of the first embodiment.
It is advantageous to polish the side faces of the arch 5, 5 ', as well as the lateral faces of the knives circular 37 and projections 51 to reduce any friction the no more possible.
We will obviously use quality steel usual for all components of the saw.
The saw according to the invention as above described has a much faster cutting speed than current saws, this being due to the shape of the tooth which is sharp on all sides mistletoe touch the tree when cutting it and thus giving it the advantage of avoiding tree cracking, a common occurrence with the other saws.
Second, given its very high inertia, it can operate at a much faster rotational speed reduced than that of current saws. In practice 700 to ~ 00 rpm is enough to ensure a perfect cut of the tree while the current saws are to rotate a speed of 1,200 to 1,500 rpm otherwise they will Frequently block in the tree. It should be noted that all engineers in the field strongly advise against manufacture log heads operating at over 800 rpm because increased saw speed increases considerably the danger of mechanical breakdown as by example pieces of metal that can come off in because of the too high speed thus increasing the risk accidents for users. With the hoop saw device according to the invention, it is now possible to reduce speed and all the risks that this entails.
Third, due to the very clean cut and smooth it makes, the saw according to the invention has the advantage

3'J7~

de ficiliter le mesurage du boi.s ainsi ~ue le classement des diverses essences de bois et aussi de ne pas tirer les fibres de l'arbre car ces fibres sont coupées très nettes et non pas arrachées comme le font les autres scies. 3'J7 ~

to facilitate the measurement of wood and thus the classification of various species of wood and also not to pull the tree fibers because these fibers are cut very neat and not torn off like other saws.

Claims

The embodiments of the invention, concerning the-which an exclusive property right or privileges is claimed, are defined as follows:

1. Circular saw comprising:
- a thin to large circular central plate diameter;
- a heavy, stiffening hoop, mounted secured to the periphery of said plate; this hoop having a thickness, in the radial direction, much less the diameter of the plate; this thickness and width hoop in the transverse direction greatly exceeding the thickness of said central plate, the dimensions above mentioned being chosen so as to increase substantially the force of inertia when sawing of a room;
- in which the outer periphery of the These are divided into dental sectors, each of which includes:
- a chip release area deploying in the radial direction;
- an outer edge, part of which forms a cutout opening, at one end, on the release area and forming a stop projection at the other end - a saw tooth housed in the cutout leaning at one end against the stop projection and being beveled at the other end, to form an edge sharp; that overhanging bevel bant the release area, and - means fixing the tooth, so removable, in the cutout.

2. A circular saw according to the claim tion 1, in which each tooth is a plate having the shape of an isosceles trapezium whose small base rests on the stop projection and has the same width as the aforementioned width of the hoop and the large base of which is formed by the cutting edge.

3 A circular saw according to claim 2, in which the cutting edge is concave towards the small base; the cutting edge and the sides of the pèze meeting to form acute angles overflowing on the outside, on each side of said hoop.

4. A circular saw according to claims 1, 2 or 3 in which the other part of the outer edge of the hoop and the external surface of each tooth, in each sector dental, are approximately coplanar.

5. A circular saw according to the claims 1, 2 or 3, in which the other part of the edge outer of the hoop and the outer surface of each tooth, in each dental sector, are approximately coplanar and are inclined, towards the center of the plate and away from the sharp edge, a angle of about 5 °.

6. A circular saw according to the claims 1, 2 or 3, in which the other part of the edge outer of the hoop and the outer surface of each tooth, in each dental sector, are approximately coplanar and are inclined, towards the center from the plate and away from the cutting edge, at an angle of about 5 °, and in which the diameter of the plate is about 25 times longer than the thick-hoop breaker and 25 times longer than its width;
the thickness of the hoop, in the transverse direction, being about 3 times the thickness of the central plate.

7. A circular saw according to the claims 1, 2 or 3, in which the hoop has a cut transverse rectangular.

8. A circular saw according to the claims 1, 2 or 3, in which the hoop has a cut square cross.

9. A circular saw according to claim 1, in which:
- the sawtooth is a rectangular plate the width of which is the same as the thickness of the hoop;
- two circular knives are attached, detachably, each on one side of the hoop; these knives having an outer perimeter protruding radial-the outer face of the sawtooth and being bevelled towards said tooth.

10. A circular saw according to the claim tion 9, in which the external lateral face of each knife is tilted towards the center of the plate central.

11. A circular saw according to the claim tion 10, in which each knife rests on a projection integral with the arch and whose external face lateral is coplanar with that of the circular knife corresponding.

12. A circular saw according to the claims tions 9, 10 or 11, in which the cutting edge of said sawtooth is straight.

13. A circular saw according to the claims 1, 2 or 3, in which the side faces of the hoop are polished and smooth.

14. A circular saw according to the claim tion 11, in which the side faces of the knives circular and protrusions are polished and smooth.

15. A circular saw according to the claims tions 9, 10 or 11, in which the other part of the edge outer of the hoop and the outer surface of each tooth, in each dental area, are approximately coplanar.

16. A circular saw according to the claims tions 4, 10 or 11, in which the other part of the edge outer of the hoop and the outer surface of each tooth, in each dental sector, are approximately coplanar and are inclined, towards the center from the plate and away from the cutting edge, at an angle of about 5 °.

17. A circular saw according to the claims tions 9, 10 or 11, in which the other part of the edge outer of the hoop and the estern surface of each tooth, in each dental sector, are approximately coplanar and are inclined, towards the center from the plate and away from the cutting edge, at an angle of about 5 °, and in which the diameter of the plate is about 25 times longer than the thick-hoop breaker and 25 times longer than its width;
the thickness of the hoop, in the transverse direction, being about 3 times the thickness of the central plate.