|Title of Invention||
A FLUIDIZED ABRASIVE POLISHING MACHINE
|Abstract||1 A -fluid!zed abrasive polishing machine comprising a fluidizing chamber disposed above a window box; a gas source for feeding gas to said chamber, through the window box and thence through a distributor, characte¬rised in that the said distributor consists of a thick fabric screen with a back plate grilli a mount provided within the said chamber for the object to be polished, the said mount being adjustable to set the angle of wipe; and means for imparting a planetary movement to the said object, during the fluidizing operation..........|
This invention relates to a fluidized abrasive polishing machine.
Product aesthetic* and lead time reduction are critical factors which add value to products in a competitive environment. The smooth finish is often essential for eye appeal and this mainly depends on the finish of the tool, especially for moulded components. Today with the advent of CAD / CAM, the machining time for complex die cavities has been considerably reduced. However* till date there is no other economically viable approach for obtaining the desired surface finish on the sculptured surfaces of moulds other than manual polishing , which is an operator dependent process and often time consuming. Any attempt to make it fast, reliable and automatic will result in reduction in lead time for dies and tools.
This invention, therefore, proposes a fluidized abra¬sive polishing machine for the efficient polishing of surfaces both sculptured and flat. By the use of the machine proposed herein it is possible to obtain a better surface roughness on the intricate surface of tools made of different materials, with a hardness
ranging -from 50 to 5B Re.
The fluidized abrasive polishing machine, according to this invention, comprises a flutdizing chamber disposed above a window box; a gas source for feeding gas to said chamber, through the window box and hence through a distributor, characterised in that the said distribu¬tor consists of a thick fabric screen with a back plate grill| a mount provided within the said chamber for the object to be polished, the said mount being adjustable to set the angle of wipe; and means for imparting a planetary movement to the said object, during the fluidizing operation.
This invention will now be described with reference to
the accompanying drawings which illustrate by way of
example one of various possible embodiments of the
machine proposed herein, wherein
Fig.l illustrates the said embodiment in assembly
Fig.2 i1lustrates the spindle, gear and pinion arrangement.
The embodiment comprises a fluidizing chamber C disposed above a window box W. Silicon abrasive particles are shown within the chamber C as black spots F.
A low pressure air B blower serves as a gas source, -for supplying atmospheric air to the said chamber, through the window box B and thence through a distributor D. A manometer M indicates the pressure within the window box B.
Conventionally, the distributor D is a perforated metal plate through which air from the window box B is distributed into the said chamber. However, in the case of the machine proposed herein, the distributor D is a thick fabric screen provided with a back plate grill. This ensures minimum pressure drop as well as the uniform functioning of all micro holes in the fabric gas distributor. This also ensures virtual elimination of all dead zones.
The top plate T provided at the top of the chamber C carries a spindle S driven by a prime mover, namely, a motor N.
A gear G is fast-mounted on the spindle S, sO that when the spindle S rotates about its axis, the gear 6 rotates along with it.
A pinion supporting bracket H is fixed to the spindle with a pinion P meshed with the gear B. Thus, when the spindle 8 is rotatably driven about its axis, the said pinion revolves around the spindle and, simultaneously, also rotates about its own axis, thus exhibiting a planetary movement.
A work holder E is provided on another bracket J which is mounted on the spindle. As the spindle S rotates about its axis, the bracket J revolves around the spindle S. The bracket J is adjustable for setting the angle of wipe of 0 - 30 deg. with respect to the horizontal plane.
The object to be polished
the shaft of the pinion P by a flexible steel rope R
provided within the chamber. Thus, when the spindle S
rotates, the work also rotates with respect to the
spindle axis as well as its own axis.
During the fluidising operation, the surface of the work gets uniformly polished, not only on the flat portions of the surface but also on the contoured and sculptured portions.
The machine proposed herein is thus eminently suited for polishing die and mould surfaces.
The terms and expressions in this specification are of description and not of limitation, there being no intention in the use of such terms and expressions of excluding any equivalents of the features illustrated and described, but it is understood that various other embodiments of the machine proposed herein are possible without departing from the scope and ambit of this invention.
1. A fluidized abrasive polishing machine comprising a fluidizing abrasive
chamber (C) disposed above a window box (W) provided with a
manometer (M) an air blower (B) adapted to feed air to said fluidized
chamber, through the said window box (W) and thence through a
distributor (D), characterized in that the said distributor (D) consists of a
thick fabric screen with a back plate grill, a top plate (T) provided at the top
of said chamber (C) and carrying spindle (S) driven by motor (N), a gear
(G) provided on said spindle (S) which is adapted such that when it
rotates, the gear (G) also rotates atongwith it, a support bracket (H) fixed
to the said spindle with a pinion (P) meshed with said gear (G), a work-
holder (E) provided on bracket (J) mounted on said spindle, the said
bracket (J) being adjustable for setting the angle of wipe from 0 to 30 "
wherein the shaft of the said work holder (E) is coupled to the shaft of said
pinion (P) by a flexible rope (R) provided within the said fluidizing
2. A fluidized abrasive polishing machine substantially as herein described
and illustrated with, the accompanying drawings.
|Indian Patent Application Number||1997/MAS/1996|
|PG Journal Number||30/2009|
|Date of Filing||12-Nov-1996|
|Name of Patentee||INDIAN INSTITUTE OF TECHNOLOGY|
|Applicant Address||IIT PO, CHENNAI - 600 036|
|PCT International Classification Number||B24C3/20|
|PCT International Application Number||N/A|
|PCT International Filing date|