AU711759B3 - Bench grinder - Google Patents

Description

AUSTRALIA

Patents Act 1990 RYOBI AUSTRALIA PTY LTD

ORIGINAL

COMPLETE SPECIFICATION PETTY PATENT Invention Title: Bench grinder The following statement is a full description of this invention including the best method of performing it known to us:- Technical Field The present invention relates to a mechanical grinder, and in particular a bench grinder.

Summary of the Invention The present invention is a bench grinder including: at least one grinding wheel; an electric motor to drive the at least one grinding wheel; a built-in lighting means held by an elongated flexible arm mounted on the bench grinder, the arm being adjustable such that the lighting means can be moved to illuminate an area of the grinder in which work takes place; a sliding coolant tray for receiving a fluid coolant; a built-in tray holding means for holding the coolant tray, wherein at least a portion of the coolant tray slides within and is concealed by the holding means, the coolant tray being removable from the holding means; and a grinding wheel dressing tool for cleaning ground-in material from the at least one grinding wheel.

The built-in light may be attached to the end of a flexible arm mounted on the bench grinder, which can be bent to direct light onto the most appropriate part of the grinder. The built-in light avoids the awkward problem of positioning an external light source to direct light onto the work area, and holding it fixed in that position.

The built-in coolant tray enables hot work pieces to be dipped and cooled in a cooling fluid. Since the coolant tray is built into the grinder, it is easily located during a grinding procedure. The built-in coolant tray of the present invention has the added advantage that it cannot spill by tipping over, unlike a separate coolant container.

The grinding wheel dressing tool helps to restore grinding wheels and improve grinding performance by removing ground-in metal from the grinding wheel surface.

The bench grinder may additionally include one or more of the following features: -an adjustable work support; -a transparent eye shield; -a built-in drill sharpening guide; -a spark deflector; -a removable safety on/off switch.

The transparent eye shield may be constructed from an impact-resistant transparent material.

One embodiment of the invention has two grinding wheels, comprising a coarse grinding wheel and a fine grinding wheel.

Brief Description of Drawings Figure 1 is a pictorial drawing of an embodiment of a bench grinder.

Figure 2 shows the bench grinder in Figure 1 with the coolant tray slid out.

Detailed Description of Drawings An embodiment of the invention will now be described with reference to Figure 1. The bench grinder 10 is designed to sit on a bench, and can be used for sharpening chisels, drill bits, axes, scissors, knives, lawnmower blades, and so on. An electric motor inside the outer casing drives two grinding wheels 20,30, and is turned on and off by a switch 35. A variety of different types of grinding wheels can be fitted onto the grinder, depending on the application. In this embodiment, there is a coarse grinding wheel and a fine grinding wheel 30. Partial wheel covers 40 are fitted around the grinding wheels to restrict the directions in which sparks can fly out. An impact-resistant transparent eye shield 50 is positioned above each of the grinding wheels by an arm 60 to protect the operator's eyes from flying sparks.

A flexible arm 70 fixed to the rear of the grinder holds a light 80, allowing the grinding area to be illuminated. A half shield 90 over the light 80 prevents light from shining into the operator's eyes. The electrical connections to the light 80 pass through a hollow passage running inside the length of the arm The grinder includes a grinding wheel dressing tool 100, which can be stored in a holder at the rear of the grinder when it is not in use. The dressing tool is operated by pressing a cleaning surface on the tool against a rotating ril~_ grinding wheel. The cleaning surface assists in extracting ground-in metal filings from the surface of the grinding wheel.

A coolant tray 110 is located at the bottom of the grinder. As shown in Figure, the tray 110 slides out from the front of the grinder, and can be filled with a fluid coolant 120. The coolant tray makes it convenient to rapidly dip a hot tool in coolant after it has been ground. The coolant tray 110 can be removed if required by sliding it all the way out from under the grinder.

It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims (3)

1. A bench grinder including: at least one grinding wheel; an electric motor to drive the at least one grinding wheel; a built-in lighting means held by an elongated flexible arm mounted on the bench grinder, the arm being adjustable such that the lighting means can be moved to illuminate an area of the grinder in which work takes place; a sliding coolant tray for receiving a fluid coolant; a built-in tray holding means for holding the coolant tray, wherein at least a portion of the coolant tray slides within and is concealed by the holding means, the coolant tray being removable from the holding means; and a grinding wheel dressing tool for cleaning ground-in material from the at least one grinding wheel.

2. The bench grinder according to claim 1, further including a built-in drill sharpening guide.

3. A bench grinder as claimed in claim 1 substantially as hereinbefore described and with reference to the accompanying drawings. Dated this thirty-first day of August 1999 RYOBI AUSTRALIA PTY LTD Patent Attorneys for the Applicant: F B RICE CO