SE1200590A1 - Saw band for wood sawing - Google Patents

Abstract

SAMMANDRAG Uppfinningen hanfor sig till ett for bandsagning i tra avsett sagband med 2differentierad tanddelning. Enligt uppfinningen är en storsta delning (a2) mellan tva narbelagna tander (8) minst 1,2 ganger storre an en minsta (ai), varvid tandhoj den (hi) hos den ena av tva tander med liten delning (ai) är storre an tandhojden (h2) hos atminstone den ena av tva tander, mellan vilka delningen (a2) är storre. Genom aft pa detta satt dels utforma tanddelningen med en val tilltagen differentiering, dels Ora spanrummen mellan tanderna 2ungefar likstora, erhaller sagbandet en god dynamisk stabilitet, som motverkar uppkomsten av sjalvsvangningar under drift, samtidigt som spantrangningar och overdriven energiatgang undviks. SUMMARY The invention relates to a saw band in three saws with a 2 differentiated tooth pitch. According to the invention, a largest pitch (a2) between two adjacent teeth (8) is at least 1.2 times larger than a smallest (ai), the tooth height (hi) of one of two teeth with a small pitch (ai) being larger than the tooth height (h2) of at least one of two teeth, between which the pitch (a2) is greater. By designing the tooth division with a choice of large differentiation, and the groove spaces between the teeth are approximately equal in size, the saw band obtains a good dynamic stability, which counteracts the occurrence of self-oscillations during operation, while avoiding tension and excessive energy access.

Description

SAGBAND FOR BANDSAGNING I TRA Uppfinningens tekniska omrade Denna uppfinning hanfor sig till ett fdr bandsagning i tra avsett sagband av det slag, som innefattar en mangfald i en tandgang ingaende tander, vilka var for sig inbegriper en mellan en spanyta och en slappningsyta avgransad skaregg, och vilka via luckor är sinsemellan atskilda med en differentierad delning, varvid den enskilda tanden har en hojd, som definieras av den transversala nivaskillnaden mellan skareggen och en botten i en framforvarande tandlucka. TECHNICAL FIELD OF THE INVENTION This invention relates to a pre-sawing in three sawn tapes of the type comprising a plurality of teeth involving teeth, each of which includes a cutting edge delimited between a chip surface and a slack surface, and which are separated from each other by gaps with a differentiated division, the individual tooth having a height which is defined by the transverse level difference between the cutting edge and a bottom in a forward tooth gap.

Uppfinningens bakgrund mom sagverksindustrin utgor bandsagning en vanlig metod fdr att avskilja mindre virkesbitar, sasom brador och planlcor fran stockar eller andra grovre amnen, sasom block. For detta andamal anvands bandsagar, i vilka ingar ett tandforsett, andlost band, vilket Loper mellan tva rullar for all med sin ena part saga snitt i stocken. Modema bandsagar har utvecklats dithan all sagbandet kan drivas med avsevard skarhastighet. I beroende av yttre omstandigheter, sasom stockens grovlek, kvalitet, temperatur, kvistinnehall, etc., kan skarhastigheten uppga till 65 m/sek eller mer. I och med all stockmatningen, dvs. den hastighet med vilken stocken langdmatas genom sagen, star i proportion till namnda skarhastighet, mojliggiirs darfcir snabba stockfloden genom sagen. Vid skarhastigheter Mom intervallet 30-65 tn/sek kan stockens matningshastighet salunda uppga till la 2 m/sek. Background of the Invention In the sawmill industry, band sawing is a common method for separating smaller pieces of wood, such as brads and planks from logs or other coarser blanks, such as blocks. For this purpose, band saws are used, in which a toothed, breathless band is inserted, which runs between two rollers for all with its one side saw cut in the log. Modema band saws have been developed where all the saw band can be operated at a considerable cutting speed. Depending on external conditions, such as the log's coarseness, quality, temperature, twig content, etc., the cutting speed can be up to 65 m / sec or more. With all the log feeding, ie. the speed at which the log is longitudinally fed through the saw, is in proportion to the said cutting speed, mojliggiirs darfcir fast log river through the saw. At cutting speeds Mom the interval 30-65 tn / sec, the log's feed speed can thus amount to 1a 2 m / sec.

Ett svarbemastrat och ofta forbisett problem i samband med bandsagning — i syrmerhet cla sagbandet är utfort med en Ann tanddelning och skarhastigheten hog — är det faktum att sagbandet kan underkastas oforutsedda sjalvsvangningar eller vibrationer. Det monterade, andlosa sagbandet är saval langt som tunt, varfor vibrationer i flertalet svangningsmoder alltid forekommer i detsamma. Den svangningsmod som framfor allt utgOr ett problem ar ndr tanden vickar och/eller vrider sig i fcirhallande till det plan, i vilket bandet i ovrigt ror sig. Denna svangningsmod paverkar icke blott den nominella spantjockleken utan aven skarkraftema, varvid systemet är aterkopplat och kan forsattas i sjalvsvangning, dvs. tanderna forsatts i vibration utan flagon yttre excitation. Det menliga resultatet av dessa sjalvsvangningar är att skareggarna dter sig in i snittytoma och ger dessa en vagig, tvattbradesliknande form. Inom fackmannakretsar benamns detta fenomen darfOr "wash- 2 boarding". I och for sig har dalama mellan narbelagna asar ett djup, som vanligen starmar inom omradet 0,1-0,2 mm. Icke desto mindre fororsakar wash-boarding ett avsevart totalt bortfall av fiberravara och darmed kdrmbara ekonomiska ffirluster. Om ndmligen den fardigsagade virkesbiten, t.ex. en brada, skall anvandas i ett forddlat skick, som kraver god planhet och ytfinish, maste ojamnheterna pa bradans bath sidor elimineras genom hyvling. Om bradan är tunn och ojamnheterna stora blir det procentuella bortfallet av trafibrer ddrffir patagligt. An answer-mastered and often overlooked problem in connection with band sawing - in particular the cla saw band is made with an Ann tooth pitch and the cutting speed is high - is the fact that the saw band can be subjected to unforeseen self-oscillations or vibrations. The mounted, breathless saw band is saval far as thin, which is why vibrations in most oscillation modes always occur in the same. The mode of oscillation which above all constitutes a problem is when the tooth oscillates and / or rotates in relation to the plane in which the band otherwise moves. This mode of oscillation affects not only the nominal frame thickness but also the shear forces, whereby the system is reconnected and can be continued in self-oscillation, ie. the teeth continued in vibration without flaking external excitation. The detrimental result of these self-oscillations is that the cuttings dive into the cut surfaces and give them a vague, water-bread-like shape. In professional circles, this phenomenon is called "washboarding". As such, the valleys between adjacent aces have a depth, which usually stares within the range 0.1-0.2 mm. Nevertheless, wash-boarding causes a significant total loss of fiber raw material and thus manageable economic losses. If, for example, the finished piece of wood, e.g. a brada, shall be used in a refined condition, which requires good flatness and surface finish, the irregularities on the brad's bath sides must be eliminated by planing. If the bread is thin and the irregularities are large, the percentage loss of fibers ddrffir becomes pataglag.

I syfte att eliminera de skadliga vibrationema och motverka uppkomsten av wash-boarding, har tidigare utforts forsok att utfora sagband med en differentierad delning mellan tanderna. Dessa fors& har emellertid varit 16ga framgangsrika, sannolikt beroende pa en bristfdllig insikt om vibrationsfenomenens natur. Aven om vibrationema i viss man ampats, har nagon acceptabel losning av problemet ej natts. In order to eliminate the harmful vibrations and counteract the occurrence of wash-boarding, previous attempts have been made to perform saw bands with a differentiated division between the teeth. However, these attempts have been very successful, probably due to a lack of insight into the nature of vibration phenomena. Although the vibrations in some people have been amplified, no acceptable solution to the problem has been found.

Uppfinningens syften och sardrag Foreliggande uppfinning tar sikte pa att undanroja bristema inom det aktuella teknikomradet och skapa ett forbattrat sagband. Ett primart syfte med uppfinningen är darffir att skapa ett for bandsagning i tra avsett sAgband, som under drift dels underkastas ett minimum av skadliga vibrationer, dels kan smidigt genomsaga trdmaterialet med ett minimum av motstand (och darmed minimal energiatgang) och utan att nypa fast i sagsnittet. Ett ytterligare syfte är att skapa ett sagband, som är enkelt att underhalla, framfor alit med avseende pa mejligheten att reparera lokala skador under bibehallande av originalsagbandets egenskaper och prestanda. OBJECTS AND FEATURES OF THE INVENTION The present invention aims to eliminate the shortcomings in the current field of technology and to create an improved saw band. A primary object of the invention is therefore to create a band sawing in three intended saw bands, which during operation is partly subjected to a minimum of harmful vibrations, partly can smoothly saw through the wire material with a minimum of resistance (and thus minimal energy input) and without pinching in the case section. A further object is to create a saw band which is easy to maintain, above all with respect to the possibility of repairing local damage while maintaining the properties and performance of the original saw band.

Enligt uppfinningen nas atminstone det primara syftet medelst de sardrag, som är angivna i patentkravets 1 kannetecknande del. Genom att utfora tandgangen med en stOrsta delning mellan tva narbeldgna tander, som är minst 1,2 ganger stone an en minsta delning, 55 och samtidigt ge den ena av tva tander mellan vilken en delning är liten, en tandhOjd som är storre an tandhOj den hos atminstone den ena av tva tander, mellan vilka delningen är maximal, vinnes dels en god dynamisk stabilitet i det operativa bandet, dels den effekten att de sasom spanrum tjanande tandluckoma blir likstora for att harbargera ungefdr lika stora spanvolymer oavsett varierande delningar. 3 60I ett foredraget utforande är den storsta delningen mellan tva tander hOgst 1, ganger stone an den minsta. Pa sá sat erhalls en valavvagd kompromiss mellan de ldngsta tandluckorna och den storsta tandhoj den. According to the invention, at least the primary object is achieved by means of the features stated in the cantilevered part of claim 1. By making the dentition with a maximum pitch between two adjacent teeth, which is at least 1.2 times stone than a minimum pitch, 55 and at the same time giving one of two teeth between which a pitch is small, a tooth height greater than the tooth height in at least one of two teeth, between which the division is maximum, a good dynamic stability in the operative band is gained, and the effect that the tooth gaps serving as span spaces become equal in size to accommodate approximately equal span volumes regardless of varying divisions. In a preferred embodiment, the largest pitch between two teeth is at most 1 times times the smallest. In this way a compromise-weighted compromise was obtained between the longest tooth gaps and the largest tooth height.

I ett tankbart utforande kan tandgangen i sin helhet inbegripa ett flertal identiska tandgrupper, som var for sig innefattar tandpar med tva olika delningar. Varje dylik tandgrupp 6kan med fordel inbegripa mellan 11 och 22 tander, som är identiskt konfigurerade i pa varandra foljande grupper. Pa detta salt vinnes dels aft den dynamiska stabiliteten blir god och likformig utmed bandets hela langd, dels aft eventuella, lokala skador pa vissa Under, later sig repareras pa ett enkelt och effektivt sat. Salunda kan den enskilda sektionen av bandet, som inbegriper en komplett tandgrupp, kapas av och ersattas av en likadan sektion, som svetsas 70fast i bandet. In a conceivable embodiment, the dentition as a whole may comprise a plurality of identical tooth groups, each of which comprises pairs of teeth with two different divisions. Each such tooth group 6 may advantageously include between 11 and 22 teeth, which are identically configured in successive groups. On this salt is gained partly because the dynamic stability becomes good and uniform along the entire length of the belt, and partly because of any local damage to certain miracles, which can be repaired in a simple and efficient way. Thus, the individual section of the belt, which includes a complete set of teeth, can be cut off and replaced by a similar section, which is welded 70fastly in the belt.

Vidare kan varje tandgrupp (t.ex. om minst 11 ander) innefatta tandpar med tre eller flera delningar, som ar inbordes olika stora. Detta bidrar till aft ytterligare forbattra sagbandets dynamiska stabilitet i jamforelse med endast tva delningar. Furthermore, each tooth group (eg if at least 11 others) may comprise pairs of teeth with three or more divisions, which are embedded in different sizes. This helps to further improve the dynamic stability of the saw band in comparison with only two divisions.

I ett utforande uppgar antalet tandpar med maximal delning, dvs. delningar inom 7intervallet 1,2 < a > 1,5, till 30% av det totala antalet tandpar. Aven detta utPirande ger en fOrbatrad dynamisk stabilitet i jamfdrelse med tandgangar med enbart ett fatal maximala delningar. In one embodiment, the number of pairs of teeth with maximum division, ie. divisions within the 7 interval 1.2 <a> 1.5, to 30% of the total number of tooth pairs. This design also provides improved dynamic stability compared to toothpicks with only a fatal maximum divisions.

I ett ytterligare utforande uppgar antalet tandpar med minimal delning, dvs. delningar inom intervallet 1,0 < a > 1,2, till minst 40% av det totala antalet tandpar. 80I ett annat utforande är tandgangen utformad sa aft samtliga skareggar tangerar en gemensam tandlinje, varvid tanderna givits varierande hojd genom aft tandluckorna gjorts olika djupa i forhallande till tandlinjen. Pa sa salt motverkas ojdnin forslitning av tanderna. In a further embodiment, the number of tooth pairs with minimal division, ie. divisions within the range of 1.0 <a> 1.2, to at least 40% of the total number of pairs of teeth. In another embodiment, the tooth passage is designed so that all the cutting edges touch a common tooth line, whereby the teeth are given varying height through the tooth gaps made different depths in relation to the tooth line. This salt counteracts the wear and tear of the teeth.

Sammanfattning av uppfinningstanken Uppfinningen bygger pa insikten att det kravs dels en vat tilltagen skillnad 8mellan den maximala tanddelningen och den minimala for aft %Ham sagbandet en dynamisk stabilitet, som till ett minimum reducerar tendensen till sjdlvsvdngning i tdnderna, dels en narmelsevis uniform volym i de spanrum, som harbargerar spanoma fran avskiljningstillfallet fram till evakueringen ur stocken. Pa sa sat motverkas menliga spantrangningar under sdkerstallande av aft bandet Riper smidigt och med minimal energiatgang genom stocken. 4 90 Kort beskrivning av bifogade ritningar Pa ritningarna är: Fig. 1en schematisk perspektivvy visande en bandsag under delning av en stock, Fig. 2en fcirstorad detaljbild visande hurusom ett sagband matas lodratt genom den samtidigt horisontellt ldngdmatade stocken, 9Fig. 3en forstorad detaljsidovy visande den geometriska utformningen hos enskilda tander ingaende i sagbandet, Fig. 4en ytterligare forstorad sektion IV-IV i Fig. 3, Fig. en partiell perspektivvy illustrerande hur sagbandets tander vickar i sidled, dá de underkastas sjdlvsvdngning, 100 Fig. 6en sidovy visande delningen mellan olika tander, som ingar i en avgransad tandgrupp i sagbandets tandgang, Fig. 7en forstorad detaljsidovy visande ett flertal i gruppen enligt Fig. 6 ingaende tander, Fig. 8 och 9 analoga detaljsidovyer visande ett alternativt sagband med en annan delning 10mellan tanderna, och Fig. en detaljsidovy visande ett tredje, alternativt utforande av sagbandet. SUMMARY OF THE INVENTION The invention is based on the realization that it requires both a very large difference between the maximum tooth pitch and the minimum for the tire. The saw band has a dynamic stability which at a minimum reduces the tendency to self-force in the teeth, and an almost uniform volume in the chambers. , which harbors the spans from the separation event until the evacuation from the log. In this way, malicious frame cracks are counteracted while securing the aft Riper belt smoothly and with minimal energy access through the log. 4 90 Brief description of the accompanying drawings In the drawings: Fig. 1 is a schematic perspective view showing a band saw during division of a log, Fig. 2 is an enlarged detail view showing how a saw band is fed vertically through the simultaneously horizontally longitudinally fed log, 9Fig. Fig. 3 is an enlarged detail side view showing the geometric design of individual teeth entering the saw band, Fig. 4 a further enlarged section IV-IV in Fig. 3, Fig. A partial perspective view illustrating how the teeth of the saw band swing laterally as they are subjected to self-oscillation, 100 Fig. 6en side view showing the division between different teeth, which form a delimited tooth group in the tooth band of the saw band, Fig. 7 an enlarged detail side view showing a plurality of teeth in the group according to Fig. 6, Figs. 8 and 9 analog detail side views showing an alternative saw band with another division 10 teeth, and Fig. a detail side view showing a third, alternative embodiment of the saw band.

Allmant om bandsagar Innan uppfinningen beskrivs mer detaljerat hanvisas till Fig. 1-5, vilka askadliggor vissa basala parametrar, som beror bandsagning som sonderdelningsmetod. I Fig. 11 visas salunda en i sin helhet med 1 betecknad bandsag under delning av en generellt med 2 betecicnad stock. Sagens vitala komponent utgors av ett dndlost sagband 3, vilket halls spdrit mellan tva rullar 4a, 4b, av vilka den undre ir drivande genom att samverka med en ldmplig drivkalla 5, t.ex. en motor. Bandet 3 delas via rullarna i tva parter 3a, 3b, av vilka den forstnamnda är operativt skarande, medan den andra toper overksamt mellan rullarna. Sasom 1tydligast framgar av Fig. 2 uppvisar bandet 3 tva motsatta och inbordes parallella ldngskanter, av vilka en forsta 6 bildar en s.k. rygg, medan den andra inbegriper en tandgang 7, i vilken ingar en mangfald enskilda sagtander 8. I arbete Loper den sagande parten 3a lodratt nedat frail den ovre rullen 4a mot den undre rullen 4b samtidigt som stocken 2 ldngdmatas horisontellt. Harvid genereras ett med 9 betecknat *sniff, via vilket en brada 10 avskiljs fran stocken. 1Den ena av sagsnittets 9 bada frilagda ytor är i Fig. 2 betecknad 11. For enkelhets skull har sagsnittets granslinje mot det osagade virket visats i form av en lodrdt granslinje 12. I praktiken kommer denna grans att utgoras av delytor, som loper snett mot stockens langdutstrackning till foljd av de kombinerade, vertikala resp. horisontella matningsrorelser, som antyds medelst pilarna. 01I Fig. 3 och 4 askadliggors hurusom var och en av tanderna 8 inbegriper en skaregg 13, vilken är avgransad mellan en spanyta 14 och en sldppningsyta 15, som successivt overgar i en botten 16 for den lucka 17, som forefinns mellan tva narbelagna tander. For att ge skareggen 13 optimal styrka är slappningsytan 15 i detta fall bruten under bildande av en primar sldppningsyta 15a, som via en brytlinje overgar i en sekundar sldppningsyta 15b. 130 Sasom framgar av Fig. 3 är ytans 15a slappningsvinkel a betydligt mindre an ytans 15b slappningsvinkel f3. Delningen mellan narbelagna tander definieras av avstandet a mellan narbelagna skareggar 13 (som awn benamns tandspetsar). I det visade exemplet tangerar samtliga tandspetsar en gemensam tandlinje TL samtidigt som luckbottnarna 16 gemensamt tangerar en undre referenslinje BL, som är parallell med tandlinjen TL. Den enskilda tandens 1116.0 h definieras av nivaskillnaden mellan tandspetsen 13 och luckbottnen 16. I Fig. 3 betecknar y den enskilda tandens spanvinkel. Av det ovanstaende framgar att Fig. 3 visar ett traditionellt sagband, vars tander har en jai= delning och likformig I Fig. 4 visas dessutom hurusom den enskilda tanden har sidoslappningar 8 till foljd av att tandens spets eller skaregg 13 givits en bredd W, som är nagot stone an sjalva 140 bandets tjocklek t. I praktiken astadkoms dessa sidoslappningar genom att spanytan 14 stukas efter det att tandgangen stansats ur bandet. General information on band saws Before describing the invention in more detail, reference is made to Figs. 1-5, which are subject to certain basic parameters which depend on band sawing as a probe division method. Fig. 11 thus shows a band saw in its entirety with 1 denoted during division of a log generally denoted by 2. The vital component of the saw is constituted by a toothless saw band 3, which is held spreading between two rollers 4a, 4b, the lower one of which is driving by cooperating with a dampable driving cold 5, e.g. a motor. The belt 3 is divided via the rollers into two parts 3a, 3b, of which the former is operatively intersecting, while the latter tooperates between the rollers. As is most clearly shown in Fig. 2, the band 3 has two opposite and embedded parallel longitudinal edges, of which a first 6 forms a so-called back, while the other includes a toothed passage 7, in which a plurality of individual saw teeth 8. In work, the sawing part 3a runs vertically downwards frail the upper roller 4a towards the lower roller 4b at the same time as the log 2 is fed lengthwise horizontally. In this case, a * sniff denoted by 9 is generated, via which a brada 10 is separated from the log. One of the two exposed surfaces of the saw cut 9 is indicated in Fig. 2 11. For the sake of simplicity, the saw line of the saw cut against the unsawn wood has been shown in the form of a vertical spruce line 12. In practice this spruce will consist of partial surfaces running obliquely towards the log. longitudinal extension as a result of the combined, vertical resp. horizontal feed motions, which are indicated by the arrows. In Figs. 3 and 4, ashes each of the teeth 8 comprise a cutting edge 13, which is delimited between a chip surface 14 and a sloping surface 15, which successively merges into a bottom 16 for the gap 17, which is present between two adjacent teeth. In order to give the cutting edge 13 optimal strength, the slack surface 15 is in this case broken to form a primary slack surface 15a, which via a breaking line merges into a secondary slack surface 15b. 130 As can be seen from Fig. 3, the clearance angle α of the surface 15a is considerably smaller than the clearance angle f3 of the surface 15b. The division between adjacent teeth is defined by the distance a between adjacent teeth 13 (as awn is called tooth tips). In the example shown, all tooth tips touch a common tooth line TL at the same time as the hatch bottoms 16 jointly touch a lower reference line BL, which is parallel to the tooth line TL. The 1116.0 h of the individual tooth is defined by the level difference between the tooth tip 13 and the hatch bottom 16. In Fig. 3, y denotes the span angle of the individual tooth. From the above it appears that Fig. 3 shows a traditional saw band, the teeth of which have a jai = division and uniform Fig. 4 also shows whether the individual tooth has side flaps 8 as a result of the tip or cutting edge 13 of the tooth being given a width W, which In practice, these lateral slacks are achieved by spraining the chip surface 14 after the tooth passage has been punched out of the belt.

I Fig. 5 illustreras schematiskt hurusom den enskilda skareggen 13 kan boja sig i sidled, om sagbandet underkastas sj dlvsvangningar. I detta sammanhang skall papekas att den bandpart 3a, som genomsagar stocken, styrs av pressbackar (ej visade), som är placerade 145 ovanfor och under stocken, och som halls anpressade mot bandpartens insida for att distinkt styra bandet. Dessa pressbackar har kontakt med bandets plana del mellan ryggen och 6 tandgangen, men val icke med sjalva tandgangen. Detta innebar att tanderna har storre frihet an sjalva bandet att röra sig i sidled om systemet underkastas sjalvsvangningar. Fig. 5 schematically illustrates how the individual cutting edge 13 can bend laterally, if the saw band is subjected to self-oscillations. In this context, it should be noted that the belt portion 3a which cuts through the log is guided by press jaws (not shown), which are located 145 above and below the log, and which are held pressed against the inside of the belt portion to distinctly guide the belt. These press jaws have contact with the flat part of the belt between the back and the 6 teeth, but do not choose with the tooth itself. This meant that the teeth had greater freedom than the band itself to move sideways if the system was subjected to self-oscillations.

Detaljerad beskrivning av uppfinningen 1Nu hanvisas till Fig. 6 och 7 resp. Fig. 8 och 9, som illustrerar tva olika utforanden av *band enligt uppfinningen. Ritningsfigurerna är schematiska och har endast till uppgift aft klargora de sardrag, som är vasentliga fOr uppfinningen, namligen tandernas delning och hojd. Detailed description of the invention 1Now reference is made to Figs. 6 and 7 resp. Figs. 8 and 9, which illustrate two different embodiments of strips according to the invention. The drawing figures are schematic and have only the task of clarifying the features which are essential for the invention, namely the division and height of the teeth.

I Fig. 6 och 7 visas en i ett forsta sagband ingaende tandgang 7, i vilken 15forekommer tva tanddelningar al och a2, vilka karaktariseras av att den storsta delningen a2 är atminstone 1,2 ganger (eller 20%) storre an den minsta delningen ai. Vidare är tandhojden hi hos den ena av tva ander, mellan vilka delningen är liten (ai), stone an tandhojden h2 hos atminstone den ena av tva ander, mellan vilka delningen a2 är stone. Genom den val tilltagna delningsdifferensen (kvot = 1,2:1) ernas en god dynamisk stabilitet i bandet under drift 160 samtidigt som de pa varandra foljande tandluckor, som bildar spanrum, blir ungefdr lika stora trots varierande langd. Med andra ord kommer spanrummen att medbringa och rymma i huvudsak lika stora mangder spanor med en vasentligen likformig kompakteringsgrad; nagot som borgar fiir att menliga spantrangningar effektivt motverkas. Ehuru den storsta delningen a2 skall vara minst 20% stone an den minsta al, bOr densamma vara hogst 50% stone. Med 16andra ord bor kvoten a2 /al ej Overskrida 1,5. Figs. 6 and 7 show a tooth passage 7 entering a first saw band, in which two tooth divisions a1 and a2 occur, which are characterized in that the largest pitch a2 is at least 1.2 times (or 20%) larger than the smallest pitch ai . Furthermore, the tooth height h1 of one of two ends, between which the pitch is small (ai), is stone and the tooth height h2 of at least one of two ends, between which the pitch a2 is stone. Due to the selected division difference (ratio = 1.2: 1), a good dynamic stability in the belt during operation 160 is obtained, at the same time as the successive tooth gaps, which form span spaces, become approximately equal despite varying lengths. In other words, the chip rooms will carry and accommodate substantially equal amounts of chips with a substantially uniform degree of compaction; something that ensures that malicious collisions are effectively counteracted. Although the largest division a2 should be at least 20% stone than the smallest a1, it should be at most 50% stone. In other words, the ratio a2 / al should not exceed 1.5.

I enlighet med ett foredraget utforande av uppfinningen inbegriper tandgangen utmed hela sagbandet ett flertal identiska tandgrupper, som var for sig innefattar forsta och andra tandpar med olika delningar. En dylik grupp — betecknad TG — visas i Fig. 6 och inbegriper i detta fall 11 ander, som är grupperade olikformigt. Raknat fran vanster i Fig. 6 170atfoljs en kort delning al av tva langa a2, tre korta al, en lang a2, tva korta al och tva langa a2. In accordance with a preferred embodiment of the invention, the tooth passage along the entire saw band comprises a plurality of identical tooth groups, each of which comprises first and second tooth pairs with different divisions. Such a group - designated TG - is shown in Fig. 6 and in this case includes 11 others, which are grouped differently. Drawn from the left in Fig. 6 170 a short division al of two long a2, three short al, one long a2, two short al and two long a2 is followed.

Denna enskilda tandgrupp gransar mot likadana tandgrupper utmed sagbandets hela langd. mom ramen for uppfinningen är det aven mojligt att mellan identiska tandgrupper anordna en eller flera andra tandgrupper med skiljaktig disposition av tanderna. Om nagon eller nagra av tanderna i en enskild tandgrupp skulle skadas, kan sagbandet repareras utan att dess 175 dynamiska egenskaper forandras. Salunda kan bandet klippas av i det parti, utmed vilket den skadade tandgruppen ingar och ersattas av ett nytt, oskadat bandparti. I praktiken kan dylika ersattningspartier integreras i sagbandet medelst svetsning. 7 Andelen tandpar med maximal delning a2 av det totala antalet tandpar i tandgangen bor uppga till minst 30% av samtliga tandpar. A andra sidan bor antalet tandpar 180 med minimal delning ai uppga till minst 40% av det totala antalet tandpar. This individual tooth group examines similar tooth groups along the entire length of the saw band. Within the scope of the invention, it is also possible to arrange between identical tooth groups one or more other tooth groups with different disposition of the teeth. Should any or all of the teeth in an individual tooth group be damaged, the saw band can be repaired without changing its 175 dynamic properties. Thus, the band can be cut off in the portion along which the damaged tooth group enters and replaced by a new, undamaged band portion. In practice, such replacement portions can be integrated into the saw band by welding. 7 The proportion of pairs of teeth with a maximum division a2 of the total number of pairs of teeth in the dentition should amount to at least 30% of all pairs of teeth. On the other hand, the number of tooth pairs 180 with minimal division should amount to at least 40% of the total number of tooth pairs.

I Fig. 8 och 9 illustreras ett sagband, i vilket de olika tanderna är arrangerade med tre olika delningar al, a2 och a3, av vilka ai är minst, a2, storst medan delningen a3 är mellanstor. I syfte aft astadkomma ungefdr likstora spanrum är de olika tandernas tandhojder h anpassade till de olika delningarna pd det salt som visas i Fig. 9. Salunda är tandhojden hi i 185 anslutning till ett kort spanrum (delning = al) storre an hojden h2 hos det ldngsta spanrummet (delning = a2), samtidigt som tandhoj den h3 for ett medellangt spanrum (delning = a3) är mindre an hi, men stone an 112. Figs. 8 and 9 illustrate a saw band in which the different teeth are arranged with three different divisions a1, a2 and a3, of which a1 is smallest, a2, largest while the division a3 is medium. In order to provide approximately equal span spaces, the tooth heights h of the different teeth are adapted to the different divisions of the salt shown in Fig. 9. Thus, the tooth height hi in 185 connection to a short span (division = a1) is greater than the height h2 of the The longest span (pitch = a2), while the tooth height h3 for a medium span (pitch = a3) is smaller than hi, but stone an 112.

I de i Fig. 6-9 visade utforandena är tandluckornas eller spanrummens bottnar 16 beldgna utmed en gemensam referenslinje BL, som är parallell med bandets rygg 6 (se Fig. 1902). I Fig. 10 visas ett alternativt utfOrande, i vilket den varierande tandhojden h1 resp. h2 astadkommits genom att tandluckorna gjorts olika djupa. Pa sä satt kan tdndernas skareggar eller tandspetsar 13 lokaliseras utmed en gemensam tandlinje TL, som är parallell med bandryggen 6, medan luckbottnarna 16 lokaliseras pa olika transversala avstand eller nivder fran bandryggen. Genom aft skareggarna forefinns utmed en gemensam tandlinje motverkas 19ojamn forslitning av tanderna. 8 In the embodiments shown in Figs. 6-9, the bottoms 16 of the tooth hatches or chambers are bulged along a common reference line BL, which is parallel to the back 6 of the belt (see Fig. 1902). Fig. 10 shows an alternative embodiment, in which the varying tooth height h1 resp. h2 was achieved by making the tooth gaps different depths. In this way, the cutting edges or tooth tips 13 of the teeth can be located along a common tooth line TL, which is parallel to the belt ridge 6, while the hatch bottoms 16 are located at different transverse distances or levels from the belt ridge. Due to the fact that the cutting edges are present along a common tooth line, uneven wear of the teeth is counteracted. 8

Claims (8)

PATENTKRAVPATENT REQUIREMENTS 1. Sagband few bandsagning i trd, innefattande en mangfald i en tandgang (7) 200 ingaende tander (8), vilka var for sig inbegriper en mellan en spanyta (14) och en slappningsyta (15) avgrdnsad skaregg (13), och vilka via luckor (17) dr sinsemellan atskilda med en differentierad delning (a1, a2), varvid den enskilda tanden (8) har en h8jd (h), som definieras av den transversala nivaskillnaden mellan skareggen (13) och en botten (16) i en framfOrvarande tandlucka, kannetecknat darav, att en storsta delning (a2) mellan tva ndrbelagna tander (8) är minst 1,2 ganger storre an en minsta (al), och att tandhoj den (hi) hos den ena av tva tander med liten delning (ai), är storre an tandhoj den (h2) hos atminstone den ena av tva tander med storre delning (a2).A saw band a few band saws in wire, comprising a plurality of teeth (8) in a tooth passage (7), each of which comprises a cutting edge (13) defined between a chip surface (14) and a slack surface (15), and which via gaps (17) dr separated from each other by a differentiated division (a1, a2), the individual tooth (8) having a height 8 (h), which is defined by the transverse level difference between the cutting edge (13) and a bottom (16) in a present tooth gap, characterized in that a largest pitch (a2) between two toothed teeth (8) is at least 1.2 times larger than a smallest (a1), and that the tooth height (hi) of one of two teeth with small pitch (ai), is greater than the tooth height (h2) of at least one of two teeth with greater pitch (a2). 2. Sagband enligt krav 1, kannetecknat darav, att den storsta delningen (a2) mellan tva tdnder (8) är hogst 1,5 ganger stone an den minsta (al). 2Saw band according to claim 1, characterized in that the largest pitch (a2) between two teeth (8) is at most 1.5 times stone than the smallest (a1). 2 3. Sagband enligt krav 1 eller 2, kannetecknat darav, att tandgangen (7) i sin helhet inbegriper ett flertal identiska tandgrupper (TG), som var fdr sig innefattar tandpar med olika delningar (al, a2).Saw band according to claim 1 or 2, characterized in that the tooth passage (7) in its entirety comprises a plurality of identical tooth groups (TG), which each comprise tooth pairs with different divisions (a1, a2). 4. Sagband enligt krav 3, kannetecknat darav, att varje tandgrupp (TG) innefattar tandpar med tre eller flera delningar (al, az, a3), som är inbordes olika stora. 25. Sagband enligt krav 3 eller 4, kannetecknat darav, att vane enskild tandgruppSaw belt according to claim 3, characterized in that each tooth group (TG) comprises tooth pairs with three or more divisions (a1, az, a3), which are of different sizes on board. Saw band according to claim 3 or 4, characterized in that accustomed individual tooth group 5. (TG) innefattar minst 11 och hogst 22 tander (8).5. (TG) comprises at least 11 and at most 22 teeth (8). 6. Sagband enligt nagot av foregaende krav, kannetecknat dirav, att av samtliga tandpar utgors 30% av tandpar med maximal delning (a2).Saw tape according to one of the preceding claims, characterized by the fact that of all tooth pairs, 30% are tooth pairs with a maximum division (a2). 7. Sagband enligt nagot av foregaende krav, kannetecknat darav, att av samtliga 2tandpar utgors 40% av tandpar med minimal delning (ai).Saw band according to one of the preceding claims, characterized in that of all 2 pairs of teeth, 40% are tooth pairs with minimal division (ai). 8. Sagband enligt nagot av foregaende krav, kannetecknat darav, att samtliga skdreggar (13) tangerar en gemensam tandlinje och att de olika tandhojderna (hi resp. h2) är astadkomna genom att tandluckorna an olika djupa i forhallande till tandlinjen. 2 9 1/4Saw tape according to one of the preceding claims, characterized in that all the cutting edges (13) are tangent to a common tooth line and that the different tooth heights (h1 and h2, respectively) are provided by the tooth gaps at different depths in relation to the tooth line. 2 9 1/4