NO790638L

NO790638L - CARBON METAL SPIRAL DRILL.

Info

Publication number: NO790638L
Application number: NO790638A
Authority: NO
Inventors: Johannes Breiting
Original assignee: Johannes Breiting
Priority date: 1978-03-02
Filing date: 1979-02-26
Publication date: 1979-09-04
Also published as: DK86679A; ES241721U; ES241721Y; JPS54127092A

Description

Hardmetallforsynt spiralbor.Carbide-tipped twist drill.

Oppfinnelsen gjelder et hardmetallarmert spiralbor, nemlig et slikt, bor som blir benyttet, for bearbeiding av grått, støpejern, NE-metaller, glass, porselen, stein o.l. Slike spiralbor har tidligere hatt. forskjellige spiss- og frivinkler, alt etter det materiale som skal bores. The invention concerns a carbide-reinforced spiral drill, namely such a drill which is used for processing grey, cast iron, non-ferrous metals, glass, porcelain, stone etc. Such spiral drills have previously had. different tip and clearance angles, depending on the material to be drilled.

Formålet med oppfinnelsen er å skaffe et hardmetallarmert spiralbor, som kan benyttes som universalbor og herved uten videre kunne trenge gjennom f.eks. såvel betong som arme-rings jern i spennbetong. Dessuten tar oppfinnelsen sikte på å utforme spiralboret på en slik måte at skarpslipingen forenkles. The purpose of the invention is to provide a carbide-reinforced spiral drill, which can be used as a universal drill and thereby easily penetrate e.g. both concrete and rebar in prestressed concrete. Furthermore, the invention aims to design the spiral drill in such a way that sharpening is simplified.

I samsvar med oppfinnelsen er det på boret .tilslipt In accordance with the invention, it is ground on the drill

skjærvinkler i følgende områder:shear angles in the following areas:

120° < 8 < 125° (spissvinkel)120° < 8 < 125° (tip angle)

10° < a < 15° (frlvinkel)10° < a < 15° (frl angle)

Det har vist seg at spiralbor med disse skjærvinkler"kan benyttes universelt,, dvs.; for boring i såvel stål som betong, glass, keramikk, o.l.,. idet man herved tilpasser, borets omdreiningstall etter det materiale som skal bearbeides. Så-ledes kan man oppnå en tilfredsstillende bearbeiding av betong med armering ved hjelp av et spiralbor ifølge oppfinnelsen ved et omdreiningstall på ca.. 2.000 r/min. Hvis man benytter slag-bor, arbeides det hensiktsmessig med et omdreiningstall på ca. 1.000 r/min. It has been shown that spiral drills with these cutting angles can be used universally, i.e. for drilling in steel as well as concrete, glass, ceramics, etc., by adapting the drill's rotation speed to the material to be processed. can a satisfactory processing of concrete with reinforcement be achieved by means of a spiral drill according to the invention at a speed of about 2,000 r/min. If an impact drill is used, it is appropriate to work at a speed of about 1,000 r/min.

Ifølge oppfinnelsen kan man øke. borets, oppsponings-evne resp. boringsytel.se. ved å overflate- eller settherde bor-s ka f.te. tV. Hardheten skal herved utgjøre mellom 40 og 55 Rc. Denne overflateherding medfører en høyning av borskaftets vridningsfasthet, hvilket resulterer i en reduksjon i borets svingninger under boringen. Dessuten medfører settherdingen at borets varmeutvidelse nedsettes i området for hardmetallskiven, idet dennes varmeutvidelse minskes i tilsvarende grad. På denne måte vil de skadelige spenninger som oppstår i området for lod-deste.det som følge av sterkt .avvikende varmeutvi deises koeffi-sienter m.h.p. hardmetall og borskaftmateriale, reduseres i høy grad. Dette motvirker at hardmetallskiven løsner. According to the invention, one can increase. the drill's chipping ability resp. boringsytel.se by surface- or set-hardening bor-s ka f.te. tV. The hardness must therefore be between 40 and 55 Rc. This surface hardening results in an increase in the torsional strength of the drill shank, which results in a reduction in the drill's oscillations during drilling. In addition, the set hardening means that the thermal expansion of the drill is reduced in the area of the carbide disc, as its thermal expansion is reduced to a corresponding degree. In this way, the harmful voltages that arise in the area of the solder as a result of strongly divergent heat will increase their coefficients with respect to hard metal and drill shaft material, is reduced to a large extent. This prevents the carbide disc from loosening.

Da spiralborets særs høye boringsytelser forårsaker utvikling av meget høye temperaturer i borets skjær, benyttes det ifølge oppfinnelsen,; for forankring av hardmetallskiven i borspis.sen et slaglodd med en varmebestandighet av ca. 1000°C. Hardmetallskiven vil derfor ikke kunne løsne ved "avsmelting". As the spiral drill's particularly high drilling performance causes the development of very high temperatures in the cutting edge of the drill, it is used according to the invention; for anchoring the hard metal disk in the drill bit, a hammer with a heat resistance of approx. 1000°C. The hard metal disk will therefore not be able to come off during "melting".

Det hardmetallarmerte spiralboret kan ifølge oppfinnelsen utformes med minst en bo.reflate. (opptaksparti). ved enden av borskaf tet, hvilken, bæreflate, som er beregnet for samvirkning med en holderanordning (chuck) , står i et. forutbe-stemt, nøyaktig stillingsforhold til hardmetallskivens bæreflate. According to the invention, the carbide-reinforced spiral drill can be designed with at least one bore surface. (admission party). at the end of the drill shank, which bearing surface, which is intended for interaction with a holding device (chuck), stands in a predetermined, exact positional relationship to the hard metal disk's bearing surface.

Denne, utforming medfører en betraktelig høyning av borets, bruksverdi. Det er som kjent nødvendig å etterslipe hardmetallskiven eller -spissen etter en viss brukstid,, for å opprettholde et tilstrekkelig skarpt skjær. Spiralboret spennes da. fast i en egnet slipemaskin. Den eneste referans.eflate, som derved står til rådighet, for å rette; inn spiralboret. i korrekt stilling før sliping, er. da hardmetallskivens sponeflate.' Innspenning av et vanlig spiralbor. for skarpsliping er en omstendelig operasjon,, fordi boret ikke kan spennes, fast; før sponeflaten strekker seg parallelt med borets, bæreflate.. This design results in a considerable increase in the drill's utility value. As is well known, it is necessary to resharpen the carbide disc or tip after a certain period of use, in order to maintain a sufficiently sharp edge. The twist drill is then clamped. fixed in a suitable grinding machine. The only reference.eflate, which is thereby available, to correct; insert the spiral drill. in the correct position before grinding, is. then the chip surface of the carbide disc.' Clamping a normal twist drill. for sharpening is a laborious operation, because the drill cannot be clamped, fixed; before the chip surface extends parallel to the bearing surface of the drill..

Ved oppfinnelsen trengs det bare et spennelemerit, som samvirker med nevnte bæreflate på spiralborskaf.tendén, eksem-pelvis i form av en enkel klemplate, som etter at den er bragt til anlegg mot borskaftendens bæreflate, automatisk setter i verk en innretting av hardmetallskivens sponeflate, som på sin side alltid strekker seg parallelt med. skivens bæreflate. In the invention, only a clamping element is needed, which cooperates with the said support surface on the spiral drill shank end, for example in the form of a simple clamping plate, which, after it has been brought into contact with the drill shank end's support surface, automatically sets in motion an alignment of the chip surface of the carbide disc, which in turn always extends parallel to. the bearing surface of the disc.

Ifølge oppfinnelsen orienterer man bæreflaten ved borskaf tenden parallelt med hardmetallskivens. bæreflate,, slik at spiralboret bringes i den vanlige utgangsstillingen for skarpsliping. According to the invention, the bearing surface of the drill shank is oriented parallel to that of the carbide disc. bearing surface,, so that the twist drill is brought into the usual starting position for sharpening.

I samsvar med oppfinnelsen er det særlig, fordelaktig å. frese inn en sliss i enden av borskaf tet., på en. slik måte at slissens hovedplan, forløper parallelt med hardmetallskivens bæreflate. Dette tillater bruk av en spesielt, enkel innspen-ningsanordning for spiralboret, som rett og slett kan skyves inn over' et stegliknende; framspring på en støtte, eller, bærer, idet steget griper inn i endeslissen. Herved fikseres spiralboret med tilstrekkelig presisjon. Deretter foretas den nød-vendige, fastspenning av boret på vanlig måte. In accordance with the invention, it is particularly advantageous to mill a slot in the end of the drill shank, on a in such a way that the slot's main plane runs parallel to the bearing surface of the carbide disc. This allows the use of a special, simple clamping device for the spiral drill, which can simply be pushed in over a step-like step; projection on a support, or carrier, as the step engages in the end slot. This fixes the spiral drill with sufficient precision. The necessary clamping of the drill is then carried out in the usual way.

Ved den sistnevnte: u.tførelsesform oppnås det spesiel-le, fordeler også på framstillingsmessig,; fordi slissen i enden av borskaftet kan freses inn i samme fresemaskin, som benyttes for innfresing av den sliss i borspissen som mottar hardmetallskiven. De to slisses, freses ved praktisk talt samme innspen-ningsstilling for skaftet fetter 180° svingning av dette. Det oppnås en tvangsmessig sikring av parallelliteten mellom sponeflaten på den senere innloddete sliss i borskaftenden. With the latter: embodiment, the special benefits are also achieved in terms of production; because the slot at the end of the drill shank can be milled in the same milling machine, which is used for milling the slot in the drill tip that receives the carbide disc. The two are slotted, milled at practically the same clamping position for the shaft plus 180° rotation of this. A compulsory securing of the parallelism between the chip surface on the later soldered slot in the end of the drill shaft is achieved.

Istedenfor endeslissen.kan borskaftenden utformes med et opphøyd eller for.senket opptaksparti for innspenning av spiralboret. Nevnte opptaksparti-.u.tforming på enden av borskaftet kan bestå av en prismatisk ansats, f.eks. seks-, eller trekantet.. Ved forsenket opptaksparti kan dette på tilsvarende måte: ha innvendig seks- eller trekantform.! I begge tilfelle får man lett håndterlige innspenningsbetingelsér,. og så snart, selve innspenningen av spiralboret er utført, skjer den ønskede automatiske stillingsfiksering av hardmetallskjæret i slipe-maskinén, helt uten ytterligere, forholdsregler. Instead of the end slot, the end of the drill shank can be designed with a raised or lowered receiving part for clamping the spiral drill. Said receiving part design at the end of the drill shaft can consist of a prismatic approach, e.g. hexagonal, or triangular.. In the case of a recessed reception section, this can similarly: have an internal hexagonal or triangular shape.! In both cases, easily manageable clamping conditions are obtained. and as soon as the actual clamping of the spiral drill has been carried out, the desired automatic position fixation of the hard metal insert in the grinding machine takes place, without any further precautions.

Oppfinnelsen forklares nærmere i det. følgende under The invention is explained in more detail therein. the following below

henvisning til tegningen som viser et u.tførelseseksempel.reference to the drawing showing an exemplary embodiment.

Fig. 1 viser et spiralbor utformet i samsvar med oppfinnelsen, sett; fra siden, og Fig. 1 shows a spiral drill designed in accordance with the invention, seen; from the side, and

fig. 2 borskaf tenden vist i oppriss, sett. bakfra. I den framre ende av et borskaft 1 er en hardmetall-skive 2 innsatt i en innfrest \ sliss 4 samt slagloddet på. vanlig måte. Ifølge oppfinnelsen er det i den bakre ende av borskaftet 1 innfrest en sliss 3. Sl issens-' 3 hovedplan, forløper parallelt med bæreflaten 5 av hardmetallskiven 2. fig. 2 drill shaft shown in elevation, set. from behind. At the front end of a drill shank 1, a carbide disc 2 is inserted into a milled slot 4 and soldered on. usual way. According to the invention, a slot 3 is milled into the rear end of the drill shank 1. The main plane of the slot 3 runs parallel to the bearing surface 5 of the carbide disc 2.

Claims

1.: Carbide reinforced spiral drill, characterized by the following cutting angle ranges:

120° < 6 < 125° (tip angle)

10° < a < 15° .(free angle)

2. Drill in accordance with claim 1, characterized in that the drill shank (1) is surface- or set-hardened.

3. Drill in accordance with claims 1 and 2, characterized in that the carbide disc (2). is attached to the drill shank (1) by means of a hammer, which has a heat resistance of approx. 1000°C.

4. Drill in accordance with one of the claims 1-3, characterized in that at least one bearing or receiving surface at the end of the drill shank (1), which bearing surface is intended; for interaction with a holding device, stands in a predetermined positional relationship to the carbide disc. (2). bearing surface (5).

5. Drill in accordance with one of claims 1-4, characterized in that the bearing or receiving surface at the end of the drill shank is parallel to that of the carbide disc (2). airfoil, (5).

6. Lives in accordance with one of the requirements 1-5. characterized by the fact that a slot (3) is milled into the end of the drill shank (1), the main plane of which runs parallel to the bearing surface of the carbide disc (2). (5) .

7. • Drill in accordance with one of the claims 1-6, characterized in that at the end of the drill shank (1) a prismatic, raised or recessed receiving part is designed with the same purpose as the aforementioned bearing surface, i.e.; for clamping the spiral drill in a holding device when sharpening the drill.