CA1333334C - Button bit grinding system - Google Patents

Abstract

This invention relates to an automated device for automatically grinding button bits for the kind of bits used mainly in drilling of underground mines, quarries, blast holes and water wells, etc. In the prior art the grinding of button bits of mining and drilling equipment has been performed manually. This manual handling is time consuming and as it requires little skill is inefficient and wasteful. The present invention seeks to overcome the disadvantages by providing an automated device for grinding button drill bits.

Description

- suTToN sIT GRINDING SYSTEM
1 ~ ~3334 This lnven~ion rel~te~ to ~n automated aevlce for automati~ally ~rinding but~on ~it~ for the kind of bi~

u~ed mainly in the drilling of underground mine~, q~rries, bla3t holes and wate~ wells, etc. In the prior art the grinding of but~on bit~ o~ mining ~nd drilling equipment ha~ been per~ormed manually. Thi~ ~anual handllng i~ time ~on~uming and as it require6 little ~kill is inefficien~ and wa~teful. The pre~ent iAvention seeks to overcome the di~adva~ageg by providing an automated 10 device ~or gr~ n~in~ button drill bits.

In a~ord~n~e wit~ the invention ~he appara~us includes means ~or ~xing a drill bit to be gr~und ~nd means for holding a grinding me~hanis~ in j~xtaposition to the bi to be ~round in~luding a robot arm having at le~st one ~rm whlch in use enables a grinding me~hani~m with it6 tool to line up in rel~tion to the but~ons ~f t~e drill bit to enable grinding thereof.

The invention will now ~e de~cribed with respect to a preferred e~bodiment in which: -Fig. l ~hows the apparatus ~ccording to ~he invention ~n ~ ~ide-~ie~: and ~ ig. 2 ~how~ a view through the drive mechani~m of the yrinqlng unit.

,. . .
Fig. 1 ~how~ drill ~$t 1, clampin~ device 2 for the ,' ~
, ~.'~

1 ~333~4 drill bit, the grinding unit 3, and the drive me~}lani~m 4.

The clamping device 2 holds a drill bit 1. ~he clamp~ng device 2 is ~upported along vertical axi-q 11 by S support 12. The ~upport 12 ha~ an ad~ustlng handle 13 which allows the clalnping devic:e 2 to be moved along axis he supporJc 1 ~ 1$ ~eld at t~e end of arm 14 by bracket 15. Br~cket 15 i8 pivot~le about an ax~s paralle~ to axi~ 11.

The other end o arm 14 ig pivoted on ~upport colu~n 16 an~ also movable along axi~ 17 o~ the column 16.

~ he space where the grinding operation is to be lS per~-ormed i9 provi~ed wlth a tran~parent shield 20.

The grlnding mechani~m 3 and lts drive mechanism 4 are ~uppor~ed by a roboti~ arm system 5. Th~ arm system 5 in~lude~ two arti~ulation~ joined at one end ~o the column 16 ~nd at ~he other end ~o d~ive mechanism ~. The ar~
~y~tem 5 is therefore rotatable a~out axi~ 17 and tran~latable in direction~ perpendi~ular to axis 17. This ar~ sy~em 5 i~ ~elf-a~u~table via the illu~trated hydrAulic or pneu~atic ~ylinder~ 6 and 7, whi~h adju~ the grlnding me~hani~m 3 in~o ~ proper lo~ation relative to the d~ill bi~ 1 and it8` tung~ten c~r~ide buttons which ~re ~o be ~harpcne~ o~ ~round.

The g~indlng mech~nl~m 3 i8 pOS~ tioned at an angle to 1 3~ 334 - the axis 11 of drive shaft 9 by clamp 21. The grinding mechanism 3 thus rotates in a conical pattern about axis 11. The grinding of all types of buttons including conical and dome type tungsten carbide buttons can be performed as well as the grinding without interference of narrow placed tungsten carbide buttons. The latter buttons are packed close to each other on the bit head leaving little space between each other especially for these buttons, so called gauge buttons, placed at the periphery of the bit. The apparatus is suitable for the regrinding of all types of bit including convex, concave, drop centre and flat faced bits, as well as bits of the threaded type or in the hole hammer type.

The grinding mechanism 3 includes a high speed motor (e.g. 18,000 - 28,000 rpm) which drives the grinding head 10 to grind a button of the drill bit 1. The motor may be powered by air, or hydraulically or electrically. The grinding mechanism 3 can, for example, comprise a "Diaroc"*
or "Super Diaroc" tool of the applicant's manufacture or other suitable tool.

The robot arm system 5 also includes supply lines or hoses to distribute water for cooling, oil for lubrication, and compressed air for the operation of the apparatus. These hoses have not been illustrated.

Fig. 2 illustrates the drive mechanism 4. This includes a motor 8 which develops a low RPM drive for the * trade-mark h o ~ 333334 ~in~ing unit 3 v~a f~rst and ~econd ~elt pulley ~eduction gear~. The~e ge~rs comprise pulleys 23 and 24 for the ~irst ge~r and pulleys 2~ and 26 for ~he se~ond ge~r.
Pulley~ 24 and 25 are driven on t~e sa~e sha~t 27 while pulley 26 drive~ shaft 9. The grinding unlt 3 is thu6 made to rotate around sha~ 9. Fittings 22 pro~ide for air and water supply to the grindin~ uni~ 3.

The robot ~r~ ~ys~em ac~ording to ~he invention i Q a mechan~sed syste~, ~here~y elimin~ting the need f~ a hand-held operation.

'rhough the invention ha,c ~een de~ribed above with r~spect to a pr~erre~ e~odiment, it is to ~e unde~stOod a~ not limi~ed ther~o. Other va~iations f~mili~r to a per~on skilled in the art are also ~on~emplated. For example, the ro~otic arm car~ be ~ade with ot~er than the two art iculations a~ ~hown. Equally the mOtor ~ can be ~onnected dire~tly to the dri~te ~haf" 9 via a planetary 20 dri~,re rather t~an V~a the belt pulley reduc:tion gears 23,

2~, 25 ~nd 2~. ln a~dition, the bit holder and ~socia~ed QUpport~ ma~ in~lude mc)re than one drill bi~c to be gxound, whether in ;~ slrl~le prote~tive hou~ing or 6hleld 20 or ~ever~1 nep~rate housing~. -~5

Claims (7)

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. An apparatus for grinding button bits including means for holding button bits in a position to be ground, a grinding mechanism equipped with a grinding tool which rotates about its longitudinal axis and further includes a grinding machine journally device which is positioned at an angle to the longitudinal axis of said grinding tool and which is operative to move the grinding mechanism so that the grinding tool is moved in an orbital path relative to the button bit to be ground with the center of rotation lying in the grinding centre of the grinding tool, where the grinding machine journalling device is moveable in the horizontal and vertical plane relative to the holding means which is stationary during the grinding operation.

2. An apparatus for grinding button bits as claimed in claim 1 wherein said journalling device is mounted on an articulated arm pivotally mounted on a vertical axis.

3. An apparatus for grinding button bits as claimed in claim 2 wherein said articulated arm comprises two segments hinged by a joint, each segment including a pair of parallel arms.

4. An apparatus for grinding button bits as claimed in claim 1 wherein said grinding mechanism further includes a high speed motor driving the grinding tool about said longitudinal axis and a low speed motor for rotating said tool at a set angle to said longitudinal axis.

5. An apparatus for grinding button bits as claimed in claim 2 wherein said grinding mechanism further includes a high speed motor driving the grinding tool about said longitudinal axis and a low speed motor for rotating said tool at a set angle to said longitudinal axis.

6. An apparatus for grinding button bits as claimed in claim 3 wherein said grinding mechanism further includes a high speed motor driving the grinding tool about said longitudinal axis and a low speed motor for rotating said tool at a set angle to said longitudinal axis.

7. An apparatus for grinding button bits as claimed in claim 4, 5 or 6 wherein said high speed motor is driven hydraulically, pneumatically or electrically and said low speed motor is driven from said high speed motor by reduction gearing.