NZ564730A - Diamond impregnated surface grinding segments of "M" or "W" shape - Google Patents

Abstract

Segments suitable for surface grinding and smoothing hard abrasive surfaces, such as concrete, are disclosed. The segments are formed of metal impregnated with synthetic diamond and are welded to a rotating circular plate, cup, or tube. The segments are of "M" or "W" shape when viewed laterally and can be of varying sizes, shapes, and grades of grit.

Description

564730 Patent Act 1953 Complete Specification 1. WM/MW segments 2. We, Holer NZ Limited, of 65 Main Road, Richmond, Nelson, New Zealand, a NZ registered company HEREBY declare the invention, for which we pray that a patent may be granted to us and the method by which it is to be performed, to be particularly described in and by the following statement - INTELLECTUAL PROPERTY OFFICE OF N.2. 18 FEB 2008 RECEIVED i 564730 3. This invention relates to synthetic diamond segments suitable for grinding and smoothing a hard abrasive surface. A diamond tool is a cutting tool which contains industrial (synthetic) diamond segments for cutting through a wide variety of materials which other cutting tools cannot. The segments are composed of diamond crystals and powdered metal which form the bond, or 'matrix', of the segments. Segments are the contact surface for cutting , grinding and drilling hard surfaces such as concrete, asphalt or stone. Segments are welded to a main body such as a cup grinder,plate, shoe, blade, steel tube (for drilling when on a core drill) or other main body and are driven against the working surface by use of a power tool. 4. Previously segments have been of a uniform shape -usually rectangular, round or a combination. This is not always the most effective shape as residue (dust) builds up, and combined with excess heat, impedes effectiveness.

Existing segment types can be limited in how the residue (dust) is dispersed from the work surface. A build up of residue on the leading edge of the segment will increase surface heat, will make the process less efficient and may possibly lead to surface glazing through reapplication of ground dust resulting in the process being ineffective.

. Previously segments have been of a uniform rectangular or round or waved shape. The round or wave shapes do to a limited degree, aid in the dispersal of residue. However, these shapes do not fully overcome the problem of residue buildup because they still do not effectively allow for a thorough dispersal of residue. 6. The object of this invention is to provide a new type of segment that will to some extent overcome the difficulty of residue dispersal. Following this text, a drawing of five of the different types of the WM segments is provided. 2 564730 7. With reference to this drawing (follows document - Page 1 of 1) — There are five variants of the invention shown. They can be affixed to a grinding plate or cup either way up. For example number 1 as viewed is in the "W" position but can alternatively be in the "M" position - hence "WM" segment. Numbers 2 through 5 are further variants of the "WM" segment which will be further described below. 8. As previously described, the segment can be affixed in the MW or WM position. This allows for less or more grinding surface or provision for residue removal. Generally, the less contact area and the greater residue removal capacity - the more aggressive the tool will be upon the surface. Conversely, affixed in a way that presents more segment contact provides for less aggressive grinding and would be more applicable in a finishing (higher grade of grit) segment for finishing a surface. With reference to the drawing - item 1 would be more applicable to the finishing (higher grade of grit) than item 3 which would be more applicable to a lower grade of grit and would be more suited to more aggressive grinding with greater pressure being applied by the operator. Item 2 is similar to Item 1 but employs different shaped vents for enhanced residue removal and cooling. Segment 3 and 4, being curved - are more applicable for use on a small diameter grinding cup and/or if more aggressive (with a lower grade of grit) grinding is required. Segment 5 is for use primarily on core drills and should preferably be used in the position shown only. The depressed spheres shown provide for improved airflow and consequently improved cooling in the confined environment of core drilling. The rounded segment surface likewise is to maximise cooling by reducing the frictional surface. The range of shapes of this invention therefore encompasses any combination of these vent shapes and sizes.

The segments can also be curved to suit the radius of the grinding cup or plate to be used.

The segment sizes range from between 20 and 60mm long, typically 40mm, up to 20mm high but typically 10 mm and up to 20 mm wide but typically 8mm wide.

The segment grades range from 16 to 400 grit and segments may be curved up to 45 degrees. 564730 9. The segment is to be welded to a grinding plate, cup or tube for drilling which is to be applied to the work surface using a rotary grinder usually powered by an electric motor. It is industry practice to use the grinder in conjunction with an industrial wet/dry vacuum cleaner to remove residue from the grinding surface. The operator will need to select an appropriate matrix of segment from the variables already described of shape, size and grade. With the grinder operating, the plate or cup holding the segments needs to be applied to the work surface. The grinder needs to be moved across the surface at a speed determined by the operator as the standard of finish is determined by sight. In the same way, the operator will be able to determine if or when different segments need to be applied to progress from a coarse to a smooth surface - the final effect, for example a matt or gloss finish is something which can be achieved by the operator depending upon the grade of segment used at the latter stages. The core drill segment (#5 on the drawing) is more appropriately used in conjunction with an electric drill rather than a grinder but is otherwise similar to use.

The application of water, to reduce friction and enhance cooling may be used with any of the segments - usually by means of a hosed supply attached to the tool being used -either a grinder or a drill. The water needs to be removed along with the residue by means of a wet/dry vacuum cleaner as previously described. While use of water is not essential - it is advisable where possible so as to reduce heat from friction and the undesirable likely result of residue reapplication and/or damage to the tool through heat.

. It will be appreciated that that the invention is broadly as is described and is intended to include elements of shape, size and grit grade of material used for the segments. 564730

Claims (2)

What is claimed is -

1. a synthetic diamond impregnated metal segment, made for surface grinding of concrete or similarly hard and abrasive material, welded to a rotating circular plate, cup or tube ( driven by a power tool), specifically of the "w" or "m" shape as viewed laterally, that can be used in the "w" or "m" position and can be of varying sizes, shapes and grade of grit as described herein.

2. A synthetic diamond impregnated metal segment substantially as described herein and in the drawings attached. Signed.... For Holer New Zealand Limited INTELLECTUAL PROPERTY OFFICE OF N.Z. 18 FEB 2001 RECEIVED 5