Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B24—GRINDING; POLISHING
  • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
  • B24D99/00—Subject matter not provided for in other groups of this subclass
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B08—CLEANING
  • B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
  • B08B7/00—Cleaning by methods not provided for in a single other subclass or a single group in this subclass
  • B08B7/02—Cleaning by methods not provided for in a single other subclass or a single group in this subclass by distortion, beating, or vibration of the surface to be cleaned
  • B08B7/024—Rotary scalers

Definitions

• This invention relates to a grinding tool having two circular rounds disposed on a spindle, and pins distributed round the spindle, which are parallel to the spindle and bridge the gap between the rounds, and rods pivotally mounted on each pin between the rounds, which project from the periphery of the rounds.
• Grinding tools of this type are used to grind and clean objects and things from coatings of various kinds, for example rust or old paint, the spindle being in ⁇ serted in a chuck on a drilling machine or other drive machine and the tool, while it is kept in rotation at high speed, up to 2500 revolutions/minute, is engaged with the surface to be treated so that the projecting rods whip against this surface and tear away the coat ⁇ ing with their ends. Since the rods are exposed to powerful stress, they are made of spring wire which is bent through a few turns to form an eye with which the , rod is passed onto . the pin.
• the pins are tubular and are secured by press fit in the rounds or - in more expensive constructions - they are secured in the rounds by ball riveting.
• the spindle is also press-fitted and/or riveted to the rounds.
• the object of the invention is to provide an improved grinding tool of the type referred to here, which allows the rods to be exchanged not only to be replaced by new, similar rods, when they are worn down, but also so as to allow exchange between rods of different types and dimensions, so that the rods can be adapted to the work for which the grinding tool happens to be used.
• the grinding tool has been given the characteristics appearing from claim 1.
• the invention also relates to an advantageous method of using such a grinding tool.
• an embodi ⁇ ment thereof will be described in more detail below with reference to the accompanying drawings in which
• FIG. 1 is an axial sectional view of the grinding tool
• FIG. 2 is an end view of the tool, seen from the left in FIG. 1, that is to say from the front end of. the tool ,
• FIG. 3 is a perspective view of the tool, seen from the front end
• FIG. 4 is a perspective view from the back end
• FIG. 5 is a perspective view of a rod which is stamped from plate or sheet material
• FIG. 6 is a perspective view of a bobbin with rods mounted thereon
• FIG. 7 is a perspective view of the tool, partially dismantled, illustrating the transfer of the rods from the bobbin of FIG. 6 to one of the pins in the tool
• FIG. 8 is an end view of a slit sleeve with rods mounted therein
• FIG. 9 is an axial sectional view of the sleeve of FIG. 8, and
• FIG. 10 is a fragmentary perspective view, partially in section, of the grinding tool with a slit sleeve, provided with rods in a modified embodiment.
• the grinding tool shown in the drawings comprises two circular steel rounds 10 and 11.
• Six bolts 12 with smooth shanks and convex heads are passed through holes in the round 10 which is fixed between the head of the bolt 12 and a steel sleeve 13 mounted with a press fit on the shank of the bolt.
• the shank is longer than the sleeve so that it projects beyond the sleeve at the other end of the bolt, where the annular end surface of the sleeve forms a shoulder on the bolt.
• the bolts 12 thus secured to the rounds 10 with associated steel sleeves 13 are uniformly distributed round the centre of the round and form pins projecting from one side of the round 10.
• a number of steel springs 14 with circular cross section are wound helically through some turns to form an eye 15 with which these steel springs are passed onto the steel sleeve 13.
• the eyes have such a fit on the sleeve that the rods can pivot freely; the play between eye and sleeve can be quite big.
• the other round 11 is passed loosely onto the bolts 12 with holes which are distributed in the same manner as the bolts round the centre of the round, and the round 11 is adjusted against the end surfaces of the sleeves 13.
• a spindle 16 is threaded with a square portion 17 through a central square opening in the round 11 and bears with a convex head 18 against one side of this round.
• the spindle With a threaded portion 19, the spindle is freely threaded through a central hole in the round 10 which is also a square opening, so that the rounds are identical .
• the rounds 10 and 11 are tightened against one another wi h the sleeves 13 as spacing members between the rounds, by means of a nut 20 which is screwed onto the threaded portion, the nut 20 being locked by means of a lock nut 21 with a washer 22 placed between the nuts.
• the spindle 16 is connected to the unit thus assembled on the spindle, for rotation therewith by means of the square portion 17 introduced into the square opening in the round 11.
• the spindle has a projecting end portion 23 with which the grinding tool described can be secured in a chuck on a drilling machine or other drive machine.
• the end portion 23 projects from the threaded portion 19 in the embodiment shown but can instead project from the head 18 which then has the form of an annular flange.
• the round 10 has a square opening for the spindle 16 like the round 11 and this means that the spindle 16 can be mounted either as shown in FIG. 1, that is to say the spindle is inserted from the left in this figure, or in the reverse position, that is to say inserted from the right with respect to FIG. 1.
• This possibility of mounting the spindle selectively from one side or the other involves an important advantage.
• the rods 14, which from the beginning are cut off square at .the free ends thereof, become worn obliquely at the ends at one side after a time, which means that the effectiveness of the grinding tool is reduced.
• the manufacturers of known grinding tools of the type referred to herein with rods which are permanently mounted in the tool recommend that the ends of the rods should be filed with a file or other tool so that the rods again have a square end face. It is easy to see that this expedient involves time-consuming work.
• the grinding tool according to the invention has been worn down at the ends of the rods 14 by grind ⁇ ing being effected with the tool rotating counter- -clockwise with respect to FIG.
• the set of rods 14 which is to be mounted on a pin 12, 13, is stored on a tubular bobbin 24 which may appropriately consist of cheap plastics material.
• the bobbin has a fixed flange 25 at one end while a flange 26 at the other end is made in the form of a head on a stopper 27 which is introduced into the tubular bobbin 24 and is held therein by means of a suitably formed spring lock or by the fact that the stopper 27 is held in the bobbin 24 by friction.
• a sleeve which is provided, with rods and is adapted to remain on the pins 12, 13 between the rounds 10 and 11 when the grinding tool according to the invention is used can be made so as to avoid said disadvantage of wear of the sleeves on which the rods are mounted. How this is done according to the invention is illustrated in FIGS. 8 to 10.
• an annular bead 28 is provided on the stopper 27 quite close to the flange or head 26 to snap into an annular groove, not shown, in the bobbin 24 and so to hold the stopper 27 detachably in the bobbin.
• FIG. 7 shows the procedure for mounting the rods 14, which are stored on the bobbin 24, on one of the pins 12, 13 after the round 10 has been removed.
• this may have a bevelled end portion 12' or alternatively the bobbin 24 may have an internal bevel in the end where the stopper 27 is fitted. It is appropriate for the bobbin 24 to have such an internal diameter that it can be passed onto the bolt 12 with an easy sliding fit, and as can easily be seen its external diameter should be sub ⁇ stantially the same as the external diameter of the sleeve 13 so that when the bobbin 24 is applied as shown in FIG. 7, it allows the eyes 15 of the rods 14 to slide easily from the bobbin 24 down onto the sleeve 13. After each pin 12, 13 has been provided with rods in this manner, the grinding tool is assembled for use in the manner previously described.
• a resilient, hardened steel sleeve 32 which has an axial slit 33 which extends over the whole length of the sleeve diametrically opposite the holes 31 arranged in an axial row.
• the steel nails 29 can be inserted into the holes 31 and the head 30 too can be introduced into the sleeve through this slit, possibly after slight resilient prizing open of the sleeve, to be engaged with the inside of the sleeve wall in front of the holes 31.
• the sleeve 32 has a bulge 34 which forms an axial bead on the outside of the sleeve and corre ⁇ sponds to an axial groove 35 at the inside of the sleeve, sufficiently large to receive the heads 30 so that the sleeve has an unencumbered circular through aperture despite the presence of the steel nails 29.
• the sleeve 32 with the nails 29 mounted therein can be passed onto one of the pins 12, 13 without being hindered by the heads of the nails, so as to have such a fit on the associated pin that the sleeve and hence the rods formed by the nails can turn easily on the pin.
• the sleeve 32 is shown mounted in this manner on one of the pins 12, 13 in the grinding tool previously described, and this figure also shows rods of a somewhat modified construction.
• the rods are here arranged in pairs in that the rods in each pair are formed from the limbs 29' of a yoke of spring wire bent into U-shape, the web 30' of the yoke being re ⁇ ceived in the internal groove in the sleeve 32 in the same manner as the heads 30.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
• Polishing Bodies And Polishing Tools (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20338130

Family Applications (1)

Country Status (5)

Families Citing this family (2)

Family Cites Families (8)

• 1979
  • 1979-05-23 SE SE7904541A patent/SE419609B/sv unknown
  • 1979-09-12 JP JP50153579A patent/JPS56500560A/ja active Pending
  • 1979-09-12 WO PCT/SE1979/000186 patent/WO1980002526A1/en unknown
• 1980
  • 1980-12-01 EP EP79901165A patent/EP0034581A1/en not_active Withdrawn
• 1981
  • 1981-01-22 DK DK28781A patent/DK28781A/da not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events