GB2310406A - A circle drawing aid with protractor and set square - Google Patents

Abstract

A circle drawing aid of the type comprising a disc 1 rotatable within an outer frame 2, wherein the disc includes a slot 6 so that lines can be drawn at a set angle. In addition the disc 1 includes a further rotatable disc 9 for drawing smaller circles. The disc and frame can be locked for use as a set square.

Description

A TECHNICAL DRAWINO AID This invention relates to a technical drawing aid Protractors are for the marking or drawing of angles which are difficult to use. The centre point of the protractor is generally placed over the centre point that the angle is to radiate from, a mark is made at the required angle indicated around the circumference of the protractor. A line is then drawn between these two points, sometimes this process needs to be repeated many times.

Compasses in general consist of dividers one end having a point and the other holding a pencil or pen container. To use this instrument the pointed end is pressed into the drawing återial and the compass is rotated around forming a circle. Skill is required to form true circles with this method.

A second method is to use a plastic template that has preset holes of different size circles, by rotating a pen or pencil around the hole a circle is formed. This method is generally used for the drawing of small size circles keeping the templates to a manageable size.

According to the present invention there is provided a drawing aid comprising of a disc or other suitable shapes, that can revolve or rotate around in any direction inside a outer retaining frame.

Whilst having a common diameter or part of a diameter with a common axis point. The disc or other suitable shape being manufactured with one or more of the following slot or slots circles, holes, or other suitable shapes. The disc can contain one or more smaller rotating discs. allowing lines, angles and circles to be drawn in various positions without movement of the outer frame.

A specific embodiment of this invention will now be described by way of example with reference to the accompanying drawings in which Figure.l. Shows a plan view of the drawing aid having a flat outer frame, with a inner disc set into this frame A second disc is set into the first larger dlec.

Pieure.2. Shows a plain view of a drawing aid with an alternative design to the full disc as shown in figure.l.

Figure.3. Shows a plan view of the drawing aid with a second alternative to the full disc as shown in figure.l.

With a round outer retaining frame.

Ref erring to the drawing aid comprising of a flat outer frame 2, 20,21 which may be square as shown in figures 1 and 2 or any other suitable shapes,two other type as shown in figures 3 The main rotating disc 1 or other suitable shapes such as 17,16 being only two types shown for example.

The main disc or other suitable shape which can revolve or rotate around in any directibn 11 inside the retaining frame 2, 20* the outer frame and disc having a clearance diameter 22* with or without bearings or other means to maintain a constant axis point 14 common to both the outer frame and disc or other shape. The main disc 1 can be manufactured with one or more inset discs 9,which can be interchangable with other same size discs,that can revolve or rotate within the main disc 1 on or on a diffrent axis 15 to the main disc 14.

The outer retaining frame 2, 20, The main disc 1, 17, 16, and inset disc 9 if fitted may be manufactured with a slot 6 or slots, circles 10,12* holes 3.

The outer frame 2,20, The main disc 1 or other shapes 17,18, and the inset disc 9 if fitted may be manufactured with markings 4,5,8,14,15 or calibrations 7,13 for example.

The drawing aid figures 1,2,3,4, may be manufactured with a lock and release mechanism 16 (only outlined) or other means allowing the disc or discs to be set into any position within there axis.

The drawing aid may be used as a protractor to draw any angle from zero through to 360 degrees. To use the drawing aid, the device is placed over the point that an angle is required at the axis point 14 of the main disc 1 so that the base line 8 is set over the base line that the angle is to be drawn from. The calibrated 13 drawing slot 6 will now be set at 90 degrees to the base line, by rotating around the outer frame while holding the main disc in position, so that the calibration 90 degrees alignes with the zero mark 0 above slot 6 the instrument is now set. By holding the outer frame 2 and rotating the main disc 1 so that the zero mark 0 above slot 6 is in line with the degree 5 required, for degrees between the marked degrees 5 around the diameter 22 of the disc, fine adjustment caibrations 7 are used.

The fine adjustment calibrations 7 are divided in to half degrees, vernier scale (not shown) for fractional divisions may be added.

Exact length of lines can be drawn using the calibrationsl3 set along the edges of slot 6. the device may also be locked into position 16 allowing similar angles to be drawn without resetting the drawing aid.

The drawing aid can be used as a compass by placing the device with centre point 14 or 15 depending on the circle required over the centre point of the circle to be drawn. By holding the outer frame 2 when using centre point 14 or holding the disc 1 when using centre point 15 place a pen or pencil in hole 3 which may be calibrated 4, a circle can be drawn by revolving 1 or 9 with the aid of the pen or pencil. Circles may also be drawn using the hole in the outer fram 2 by the sam method.

Circles may also be drawn using the pemade circles 10,24

Claims (12)

1. CLAIMS Claim.l. A draviing aid comprii of n disc or other suitable shapes, that can revolve or rotate around in any direction inside a outer retaining frame.Whilst having a common diameter or part of a diameter with a common axis point. The disc or other suitable shape being manufactured with one or more of the following slot or slots,circles,holes,or other suitable shApes, the disc can contain one or more smaller rotating discs.

   allowing lines, angles and circles to be drawn in various positions without movement of the outer frame.

   Claim.
2. 2. A drawing aid as claimed in claim 1 wherein an outer frame which can fully revolve around a centre disc, Allowing lines and circles to be drawn in various positions without movement of the centre disc.

   Claim.
3. 3.A drawing aid as claimed in claim 1 or claim 2 wherein a disc or discs may be fitted inside a main disc.

   Which can fully revolve around inside the main disc allowing line, angles, circles or holes to be drawn on a different axis to the main disc.

   Claim.
4. 4. A drawing aid as claim 3 wherein a disc or other discs and retaining frame are marked with calibrations to allow the accurate positioning of the discs in any position within there axis.

   Claim.
5. 5. A drawing aid as claimed in any preceding claim wherein in which the disc or discs may be locked in any position.

   Claim.
6. 6. A drawing aid as claimed in claims 1 to 5 wherein a disc manufactured with a drawing slot that passes through the bxls point of a drawing disc.

   Claim.
7. 7. A drawing aid as claimed in claim 6 wherein a disc vrith a marked base line that passes through the axis point at right angles to a drawing slot.

   Claim.
8. 8. A drawing aid as claimed in any preceding claim wherein a disc with holes, which may or may not be calibrated from the axis point allowing accurate size circles to be drawn.

   Claim.
9. 9. A drawing aid as claimed in claims 1 to 8 wherein, the main outer frame, the main disc and discs fitted within the main disc. Can be all rotated at different stages allowing patterns to be drawn0 Claim.
10. 10. A drawing aid as claimed in claim 7,8 and 9 wherein a disc locked in position in an outer frame with a drawing slot, being a set square, for any angle.

    Claim.
11. ll. A drawing aid as claimed in any preceding claim wherein made from clear materials.

    Claim.
12. 12. A drawing aid substantially as described herein with reference to figure.l.2.3. of the accompanying drawings.