NO125201B

NO125201B -

Info

Publication number: NO125201B
Application number: NO3607/69A
Authority: NO
Inventors: N Jonsson; J Lagerstedt
Original assignee: Atlas Copco Ab
Priority date: 1968-10-04
Filing date: 1969-09-10
Publication date: 1972-07-31
Also published as: DE1946734B1; CH519092A; FR2019899A1; US3565187A; FI54733C; SE324546B; JPS4827041B1; GB1237859A; DE1946734C2; FI54733B

Description

Trykkmediumpåvirket gripeanordning. Gripper affected by pressure medium.

Denne oppfinnelse vedrorer en trykkmediumpåvirket gripeanordning som inngår i et fjell- eller jordboreaggregat for roterende boring og er anordnet til å gripe om en borstreng for å overfore rotasjon eller aksialbevegelse til borstrengen, hvor gripeanordning en omfatter et maskinelt roterbart hus i hvilket i det vesentlige radialt mot borstrengen bevegelige gripebakker er anordnet rundt borstrengen. This invention relates to a gripping device influenced by pressure medium which is part of a rock or soil drilling unit for rotary drilling and is arranged to grip a drill string in order to transfer rotation or axial movement to the drill string, wherein the gripping device comprises a mechanically rotatable housing in which essentially radially towards The drill string movable grab jaws are arranged around the drill string.

Ved en kjent utforelse av en slik gripeanordning benyttes radialt mot borstrengen virkende stempler i hydrauliske sylindere for å påvirke gripebakkene i radial retning til inngrep med borstrengen. For å oppnå tilstrekkelig store gripekrefter måtte sylind-rene gjores så store at gripeanordningen ble uhensiktsmessig stor. Dessuten innebærer anvendelsen av stempler som er glidbare i sylindere alltid en viss oljelekkasje som kan medfore nedsatt friksjon In a known embodiment of such a gripping device, pistons acting radially towards the drill string are used in hydraulic cylinders to influence the gripping jaws in a radial direction to engage with the drill string. In order to achieve sufficiently large gripping forces, the cylinders had to be made so large that the gripping device became inappropriately large. In addition, the use of pistons that slide in cylinders always involves a certain amount of oil leakage, which can lead to reduced friction

mellom gripebakkene og borstrengen. between the grippers and the drill string.

Hensikten med. oppfinnelsen er å unngå de nevnte vanskelig-heter og tilveiebringe en gripeanordning av det innledningsvis angitte slag som til tross for at den frembringer store gripekrefter har små dimensjoner og er billig i fremstilling. Oppfinnelsen ut-merker seg ved de i patentkravene angitte trekk. The purpose of. the invention is to avoid the aforementioned difficulties and to provide a gripping device of the type indicated at the outset which, despite the fact that it produces large gripping forces, has small dimensions and is cheap to manufacture. The invention is distinguished by the features specified in the patent claims.

Oppfinnelsen skal forklares nærmere ved hjelp av eksempler under henvisning til tegningene hvor fig. 1 er et sideriss til dels i snitt av et fjell- og jordboreaggregat hvor en gripeanordning ifolge oppfinnelsen finnes, fig. 2 viser et snitt i det vesentlige langs linjen 2-2 på fig. 1, fig. 3 i s.torre målestokk noen detaljer fra fig. 2, fig. 4 viser i stdrre målestokk et snitt i det vesentlige langs linjen 4-4 på fig. 1 hvor gripeanordningen er vist i snitt langs linjen 4-4 på fig. 2, og fig 5 viser et tverrsnitt av en modi-fisert gripeanordning. The invention shall be explained in more detail by means of examples with reference to the drawings where fig. 1 is a side view, partly in section, of a rock and soil drilling unit where a gripping device according to the invention is found, fig. 2 shows a section essentially along the line 2-2 in fig. 1, fig. 3 in s.torre scale some details from fig. 2, fig. 4 shows to a larger scale a section essentially along the line 4-4 in fig. 1 where the gripping device is shown in section along the line 4-4 in fig. 2, and Fig. 5 shows a cross-section of a modified gripping device.

Fjell- og jordboreaggregatet IO som er vist på figurene The rock and soil drilling unit IO shown in the figures

har en raatningsbjelke 11 som bæres av ekspansjonsbolter 12. Matningsbjelken kan istedet bæres av et hjulbåret understell eller på annen måte om det skulle finnes hensiktsmessig. En sleide 13 som bærer et borlegeme 14 er glidbart langs matningsbjelken 11 idet den kan for-skyves ved hjelp av to parallelle kjeder 15, en kjede 16 og en mat-ningssylinder 17 med to trykkmediumtillop 17a. På matningsbjelkens 11 fremre del finnes en borholder 18, som er anordnet dels for under boring å styre en borstreng, i dette tilfelle et skjotet borror 19, og dels for å fastholde borroret 19 og hindre rotasjon og aksial bevegelse av dette f.eks. under skjoting eller oppbryting av skjoten. En diamantborkrone 20 er fastskrudd i horrorets 19 fremre del og spylevann tilfores gjennom en vannsvivel 47 som er påskrudd horrorets ende. I borlegemet 14 som er vist i snitt på fig. 4 inngår en gripeanordning eller kjoks 21 ifolge oppfinnelsen. Denne kjoksen har et hus 22 som er roterbart lagret i borlegemets 14 hus 23 ved hjelp av et rullelager 24 og et kulelager 25. Et lokk 37 utgjer en losbar gavl på kjokshuset 22. Trykkmedium, fortrinnsvis trykkolje, tilfores gjennom en slange 26 og gjennom et sirkulært spor 27 i huset 23 til en kanal 28 i kjoksens 21 hus 22. Oljen tillates å lekke gjennom en sirkulær spalte 29 med fortrinnsvis 0,01-0,05 mm bredde som finnes mellom det stillestående hus 23 og det roterende kjokshus 22. Denne olje oppsamles og ledes, gjennom en slange 30 tilbake til tanken. Tetningsringer 31 er anordnet for å tette mot den olje som har passert spalten 29 og således baxe har atraosfæretrykk. has a feeding beam 11 which is carried by expansion bolts 12. The feeding beam can instead be carried by a wheel-borne undercarriage or in another way if it should be found appropriate. A slide 13 which carries a drill body 14 is slidable along the feed beam 11 as it can be moved by means of two parallel chains 15, a chain 16 and a feed cylinder 17 with two pressure medium inlets 17a. On the front part of the feed beam 11, there is a drill holder 18, which is arranged partly to guide a drill string during drilling, in this case a jointed drill bit 19, and partly to hold the drill bit 19 and prevent its rotation and axial movement, e.g. during splicing or breaking up of the splicing. A diamond drill bit 20 is screwed into the front part of the horror 19 and flushing water is supplied through a water swivel 47 which is screwed onto the end of the horror. In the drill body 14 which is shown in section in fig. 4 includes a gripping device or yoke 21 according to the invention. This cooker has a housing 22 which is rotatably stored in the housing 23 of the drill body 14 by means of a roller bearing 24 and a ball bearing 25. A lid 37 forms a removable end on the cooker housing 22. Pressure medium, preferably pressure oil, is supplied through a hose 26 and through a circular groove 27 in the housing 23 to a channel 28 in the housing 22 of the cooker 21. The oil is allowed to leak through a circular slot 29 with a preferably 0.01-0.05 mm width that exists between the stationary housing 23 and the rotating cooker housing 22. This oil is collected and led through a hose 30 back to the tank. Sealing rings 31 are arranged to seal against the oil that has passed through the gap 29 and thus has atmospheric pressure.

Sn reverserbar hydraulisk rotasjonsmotor 46 er anordnet for å dreie kjoksens 22 hus gjennom en tannhjulsveksler som har tannhjul 32, 33 festet med kiler 34. Et hyIseformet og med flens forsynt stempelelement 35 av et elastomert materiale f.eks. gummi, er innspent med sine flenser 36 i kjoksens hus 22. Til innspennin-gen benyttes kjokshusets lokk 37 og en sirkulær avstandshylse 38 med hull 39. Således adskiller stempelelementet 35 et trykkrom 40 som har forbindelse med kanalen 28, fra et sentralt rora 41 gjennom hvilket borroret 19 kan innfores. I dette sentrale rom 41 er gripebakker 42 anordnet for ved trykkoljepåvirking av stempelelementet 35 å kunne gripe borroret 19. Styrepinner 43 er festet i kjoksens hus 22 og lokk 37 som er anordnet for å styre gripebakkene 42 i deres radiale bevegelse. Når kjoksen 21 roteres, kommer styrepin-nene 43 til å overfore dreiemomentet direkte fra kjoksens hus 22 til gripebakkene 42 slik at stempelelementet 35 ikke utsettes for dreiemoment. Sn reversible hydraulic rotation motor 46 is arranged to rotate the housing of the cog 22 through a gear changer which has gears 32, 33 attached with wedges 34. A sleeve-shaped and flanged piston element 35 of an elastomeric material e.g. rubber, is clamped with its flanges 36 in the cooker's housing 22. For the clamping, the cooker's lid 37 and a circular spacer sleeve 38 with holes 39 are used. Thus, the piston element 35 separates a pressure chamber 40, which is connected to the channel 28, from a central rora 41 through which the drill 19 can be inserted. In this central space 41, gripping jaws 42 are arranged to be able to grip the drill bit 19 when pressure oil is applied to the piston element 35. Guide pins 43 are fixed in the housing 22 of the chuck and lid 37 which is arranged to control the gripping jaws 42 in their radial movement. When the yoke 21 is rotated, the guide pins 43 will transfer the torque directly from the yoke's housing 22 to the gripping jaws 42 so that the piston element 35 is not subjected to torque.

Mellom aksiale spor 44 i nærliggende bakker 42 finnes fjærer i form av f jærblad 45 innspent for normalt å holde bakkene ut av gripestilling. Disse fjærblad 45 danner sammen med gripebakkene 42 en sylindrisk mantelflate mot hvilken stempelelementet vil stotte seg når det påvirkes av trykkolje gjennom slangen 26. Stempelelemen-tets 35 trykk på fjærene 45 overfores derved til gripebakkene 42 som medforer okt gripekraft. Between axial grooves 44 in nearby slopes 42 there are springs in the form of leaf springs 45 tensioned to normally keep the slopes out of gripping position. These spring blades 45 together with the gripper jaws 42 form a cylindrical mantle surface against which the piston element will rest when it is affected by pressure oil through the hose 26. The pressure of the piston element 35 on the springs 45 is thereby transferred to the gripper jaws 42 which results in increased gripping power.

Gripebakkene 42 har hensiktsmessig ytre kanter 48 avfaset som vist på fig. 3 slik at overgangen mellom fjærene 45 og gripebakkene 42 blir myk. Dette medforer dels at ingen skarpe hjorner og kanter sliper på stempelelementet og dels at hele stempelelementet 35 understottes når gripebakkene er i gripestilling. Oljetrykket mot stempelelementet 35 er antydet med piler på fig. 3. The gripping surfaces 42 suitably have outer edges 48 chamfered as shown in fig. 3 so that the transition between the springs 45 and the gripping surfaces 42 is smooth. This means that no sharp corners and edges grind on the piston element and that the entire piston element 35 is supported when the gripping jaws are in the gripping position. The oil pressure against the piston element 35 is indicated by arrows in fig. 3.

Ettersom stempelelementet således er i sin helhet under-støttet og ikke overforer noe dreiemoment, behover det heller ikke å armeres. Dette medforer at stempelelementet som sådant blir enkelt og billig å fremstille. As the piston element is thus entirely supported and does not transmit any torque, it does not need to be reinforced either. This means that the piston element as such is easy and cheap to manufacture.

Fjærbladet 45 kan alternativt festes mot gripebakkene med The spring blade 45 can alternatively be attached to the grippers with

skruer eller nagler. screws or rivets.

Ved den modifiserte kjoks som er vist på fig. 5 er detaljer som svarer til detaljene på de foregående figurer angitt med samme referansetall. Fjærene 45 er i dette tilfelle skruefjærer og gripebakkene 42 danner hele den mantelflate som stotter stempelelementet 35. Stempelelementet 35 er identisk med det som er vist på fig. 1-4. In the modified cooker shown in fig. 5, details corresponding to the details of the previous figures are indicated with the same reference number. In this case, the springs 45 are coil springs and the gripping jaws 42 form the entire mantle surface which supports the piston element 35. The piston element 35 is identical to that shown in fig. 1-4.

Claims

1. Pressurized medium-affected gripping device (21), which is part of a rock or soil drilling assembly (10) for rotary drilling and is arranged to grip a drill string (19) to transfer rotation and/or axial movement to the drill string, comprising a rotatable housing (22), in which gripper jaws (42) which move essentially radially towards the drill string are arranged around the drill string, characterized in that a sleeve-shaped piston element (35) of elastomeric material is clamped in the housing (22) in order to separate a pressure medium supply arranged pressure space (40) between the housing (22) and the piston element (35) from a central space (41) in which the gripping jaws (42) are arranged, as well as by the piston element (35) being arranged to influence the gripping jaws (42) to engage with the drill string (19) when pressure medium is supplied to said pressure chamber (40).

2. Gripping device according to claim 1, which is mechanically rotatable, characterized in that said gripping jaws (42) are controlled by control means (43) which are firmly connected to the housing (22) and arranged to transfer the torque from the housing (22) to the gripping jaws ( 42) when the housing (22) is rotated.

3. Grip device according to claim 2, characterized in that said control device (43) is made of control pins (43) fixed between the gables of the house.

4. Gripping device according to claims 1 -3, characterized in that springs (45) are arranged to keep the gripping jaws (42) out of the gripping position when the pressure is not applied to said pressure chamber (40).

5. Gripping device according to one or more of the preceding claims, characterized in that the gripping jaws (42) are included as an element in a cylindrical casing surface which is arranged to provide support for essentially the entire inner casing surface of the sleeve-shaped piston element (35) when the pressure is applied said pressure chamber (40).

6. Gripping device according to claims 4 and 5, characterized in that said springs are made of spring blades (45) which are attached between nearby gripping jaws (42) and which are arranged together with the gripping jaws (42) to form said supporting cylindrical mantle surface.

7. Grip device according to one or more of the preceding claims, characterized in that the piston element (35) has flanges (36) which are sealingly clamped into the housing (22) of the gripping device by means of an end (37) to the housing (22) and a spacer sleeve (38) arranged between the flanges (36).