FIELD OF INVENTION

The present invention relates to a drawing instrument. More particularly it relates to a drawing instrument with improved features that facilitate drawings.

BACKGROUND OF THE INVENTION

There are numerous triangles, compass, set square and protractors commercially available in the market that performs one or more functions which is known in the art. Such devices are also being used by architects, mechanical draftsmen, designers, artists, teachers, students and others having use for an instrument of this character .

A user using old method or conventional way, hunts his instrument-box for a particular triangle, compass, straightedge, protractor or compass to measure a particular angle or to construct a desired angle. The object of the present invention is tree of movable parts and improves speed in which users learn to measure, draw and obtain answers of different level of mathematical topics in more convenient way.

The conventional way to draw a reflected image (103) from an object (101), is illustrated in Fig .1A, 1B, 1C, 1D, 1E & 1 F. The figures shows how users use set square and ruler in order to draw the desired drawings. The description below shows how user currently draw reflected images and marks the points of intersect for angle (90°) on the reflection axis illustrated in FIG 1 B. Based on FIG .1 C, the measurement is taken from origin point P to the reflection axis using ruler and marks the other side of the line FIG IE. The above steps are repeated for other vertices. The reflected image of FIG 1 F is drawn.

The conventional way to construct the centre of rotation (201) illustrated in FIG 2 A, 2B, 2C, 2D, 2E and 2F requires a ruler, compass and protractor. By using a ruler, user draws a joining line of vertex B and B' in FIG 2B and then uses a compass to construct the perpendicular bisector as in FIG 2C. The point of intersect is obtained from the compass and line is drawn FIG 2D. The same steps above are repeated for vertex C and C; and the intersection of perpendicular bisector line is the centre of rotation FIG 2E. A protractor is used to confirm the angle. When using mis improved invention the answer is obtained in a single measurement and requires less time. The description below explains the current way of drawing image illustrated in FIG 3A, 3B, 3C and 3D. These steps require users to pick up ruler, compass and protractor at different time and draw lines based on its requirement. First the user identifies a suitable vertex and uses the protractor to mark the desired perpendicular angle FIG 3B. Fix the opening of a pair of compass to the exact length of the line joining centre of rotation (201) to the vertex point B and mark on line FIG 3C. The user corresponds the line of cross as image of point B' FIG 3C. The above steps are repeated for other vertices in the picture FIG 3A .This way of drawing image in FIG 3A is time consuming and requires various tools.

The way of drawing in FIG 1, FIG 2 and FIG 3, generally suffer the disadvantages of inefficiency, resulting the need to use more man one instrument, whereby the instruments are required to move back and forth from one instrument to the other, in order to complete the operation and the given task.

According to this research from the International Journal of New Trends in Arts, Sports & Science Education (IJATASE) has a Journal "Misconceptions in Geometry and Suggested Solutions for Seventh Grade Students" (ISSN: 2146-9466) (Year 2012 :0¾erem) shows the results from the study revealed that seventh year secondary school students have a number of misconceptions and lack of knowledge related to geometry subject. The report on page 30 explains the mistakes made by wrong use of tracing paper therefore produced a wrong rotation of images and mislearned measurings.

Besides that, there is a Journal "Understanding Students Misconceptions: An Analysis of Final Grade 12 Examination Questions in Geometry" by Kakoma Luneta, Phythagoras, Volume 36, No 1 Year 2015 (ISSN : 1021-2346) (Year 2015-Kakoma Luneta) tells that the most common errors were procedural and students were not able to engage with simple geometric relationships, reflections on particular line and rotation of shapes in standard angles of 90°, 180° and 360°. The Journal mentioned that every question answered has a high occurrence of procedural errors or conceptual errors. My preferred embodiment has successfully solved the problem above.

According to this research, "The teaching of Geometric (Isometric) Transformation at Secondary School Level: What Approach to Use and WhyT by Samuel Mashinggaidze from Department of Applied Education; Faculty of Education, Midlands State University, Gweru, Zimbabwe. (ISSN: 191 l-2017)(Asian Social Science, Vol. 8, No IS, Year 2012) has emerged in this write-up that the teaching of transformation should always commence with practical approach - the graphical approach to consolidate understanding. It also states that first learners, need to understand, try to visualise and draw for promoting their relational knowledge and conceptual understanding of transformations. The Journal on An Investigation into the Challenges In-Service Student Teachers Encounter in Transformational Geometry, " Reflection and Rotation " The Case ofMufulira College of Education, by, Dennis Kambilombilo , Whyson Sakala . School of Mathematics and Natural Sciences, Copperbelt University, Kitwe, Zambia.

(Journal of Education and Practice Volume 6, No 2 Year 2015) (ISSN: 2222-1735) shows study conducted and concluded that in-service mathematics student teachers encounter serious challenges in transformational geometry; reflection and rotation. However, the present invention substantially, can strengthen the understanding of transformational geometry, including mechanical and content knowledge as well.

The importance of transformations in geometry is now more widely accepted, and educators have begun to realize the place of transformations in the study of high school geometry (Usiskin, 1974). Transformations gained some prominence in the "modern mathematics" movement of the nineteen-sixties and have always been considered part of the study of informal geometry (DriscoU, 1983).

The embodiment significantly improves an overall student comprehension on Mathematics and reduces the time to teach students on how to understand mathematical concept and principle which can be demonstrated graphically by methods of drawing different aspects in transformation, drawing circles, tangenial line and obtaining centre of circle which has not been demonstrated yet for school students, using a set square. The invention is not only for students and teachers, but it also caters for professional draftsmen and architects as a drafting tools, who expect precision and accuracy in their tasks.

SUMMARY OF THE INVENTION

According to the present invention, a drawing instrument comprising: a first side that is perpendicularly connected to a second side; a third side that is connected to the first side and/or the second side forming a set or a body of the instrument. Each of the sides includes an edge for drawing a line and measuring a distance. The edge may be beveled and marked with measurements, scales or intervals.

A line with interval points or holes is provided on the instrument as a compass line. The line maybe disposed on any one of the sides for drawing a circle. The line with interval points includes a first point B with an interval that is 2 times of a predetermined distance or measurment value from an initial point or a starting point A. For example the predetermined distance value is 0.1cm which results in the point B that is 2 times of the value which results in an interval of 0.2cm from the initial point A; a second point F with an interval that is 3 times of the value which results in an interval of 0.3cm from the initial point A. The initial point A is preferably marked as '0' or '0.0' . The series further includes a third point G with an interval that is 5 times of the value, which results in an interval of 0.5cm from the initial point A. The third point G includes an interval that is 2 times of the value which results in an interval of 0.2cm from the second point F. The series further includes a fourth point H with an interval of 10 times of the value which results in an interval of 1.0cm from the initial point A. The series further includes a fifth point I with an interval that is 5 times of the value which result in an interval of 0.5cm from the fourth point H. These interval points may be parallel to any one of the sides.

The drawing instrument further comprising a first pivot hole disposed at a vertex which is the connection point of the first side and second side; and a second pivot hole mat is in line with the first pivot hole and disposed on a mid-point of the third side.

The drawing instrument further comprising an internal slit within the set which is parallel to the third side forming a fourth side.

The drawing instrument further comprising an internal curved edge to act as a protractor wherein the curved edge includes intervals or scales for an angular measurement and a third pivot hole disposed on a mid-point of the fourth side to act as the centre rotation of the protractor.

The above features such as number of lines, scales, holes and marks, aligned in accordance; whereby it correlates and overlaps' with one another to facilitate speed, accuracy and solve multiple solutions simultaneously. The bevels along the edges of the instrument is to avoid most of the effects of reflection and refraction of lines and scales underside of the ruler.The thickness of the instrument, for example, may be greater or less width from one* twentieth to one-fourth of an inch thickness, depending on the length of the ruler. The length of the sides may vary. For example, each side may have a length of twelve centimetre, or more depending on the requirement

A hemispheric bumper is integrally formed with the body of the instrument. One or more hemispheric bumpers may be provided below the instrument. Raising the instrument above the drafting surface facilitates movement and eliminates smearing of ink under the instrument and between it edges, as well as reduces friction associated with sliding of the instrument on the drafting surface.

The height of the first pivot hole allows users to place a marking device such as a pencil on the paper through the hole in order to mark the centre point of rotation. The first pivot hole acts as a centre of rotation and to draw 90° images based on the given object. Positioned at the intersection of perpendicular line between the first and second sides, it allows users to measure, mark and rotate the instrument about the centre of rotation using the first pivot hole. The principle feature of the first pivot hole marks the combination of perpendicular angle and the uniform bisector measurement between the first and second sides. This feature significantly saves time and is used in constructing image for 90° rotation and finding centre of rotation between two images under 90° rotation. Besides that, it also assists to find the centre of rotation from two images under any angle (0°) of rotation, to draw the reflection axis from two images and to draw lines of intersection for centre of circle.

The height of a second pivot hole allows user to place a marking device such as a pencil on the paper through the hole in order to mark the centre point of rotation and to measure uniform bisector measurement along the third side. The second pivot hole is positioned in a mid-point of the third side.

The second pivot hole acts and marks as a centre of rotation to draw 180° rotation images based on the given object wherein the hole allows users to measure, mark and rotate about the centre of rotation. The second pivot hole marks the uniform bisector measurement between a first section and second section of the third side. These third pivot hole and third side significantly saves time and is used in constructing image for 180° rotation , finding centre of rotation between two images under 180° rotation, constructing images under reflection, finding reflection axis from given two images and constructing parallel line. The third side may be provided with numeral intervals with the second pivot hole acts as the initial or starting point for measurement.

A line perpendicular to the third side may be provided, This perpendicular line together with the third side allow users to find centre of rotation from two images under unspecified angle of rotation (θ°), constructing images from reflection line, finding reflection axis from two images, and constructing parallel line. The perpendicular line extends from the vertex or the first pivot hole to the second pivot hole.

The third pivot hole is located on the intersection between the perpendicular line and the fourth side. Hie height of the third pivot hole allows users to place the marking device such as a pencil on the paper through the hole for marking the centre point of protractor and to measure uniform bisector measurement along the forth side. The hole acts and marks as a pivot point of rotation, to draw images of any angle of rotation based on the object that allow users to measure, mark and rotate about the centre of rotation using the hole. Hie principle feature of the third hole is to mark the centre point of protractor, a rotating centre dial for all vertex points in the diagram. The third pivot hole is in line with the bottom left edge and a bottom right edge of the slit which creates a uniform bisector measurement to the fourth side and to the protractor along with the perpendicular line. This third pivot hole significantly saves time and is used in constructing images for any angle of rotation (θ°), finding centre of circles of various diameter and constructing tangenial line from a given point on the circle. Besides that, it also assists to find the centre of rotation from two images constructed from unspecified angle of rotation (θ°) and constructing parallel line.

The internal curved edge that acts as a protractor may be formed by a cut-out of a semi-circle from the body of the instrument leaving an opening. A perpendicular ruler may be provided on the perpendicular line and the operiing. It may extend from the fourth side which may devide the opening into two areas. One end of the internal curved edge may connects to a first upper edge of the slit and the other end connects to a second upper edge of the slit.

The line with interval points is in the form of a line. The series allows user to draw a circle and construct an angle. Any one hole of the series may act as a centre point of a circle and a corresponding hole may act as a moving point which draws the circumference of a circle.

A fourth pivot hole is provided on the perpendicular line which is between the first pivot hole and the third pivot hole. The fourth pivot hole acts as a reference point and an additional point to mark on the paper in order to increase the accuracy of the drawing. Examples of the operation that can be performed using the present invention include:

1. Constructing an image of 90° rotation, based on object and a point of rotation.

2. Constructing an image of 180° rotation, based on object and a point of rotation.

3. Constructing an image of any oblique angle (6°) of rotation, based on the object given and a point of rotation.

4. Finding the point of rotation based on two images of 90° rotation respectively.

5. Finding the point of rotation based on two images of 180° rotation respectively.

6. Finding the point of rotation based on two images with 9° rotation (θ° - unspecified angle of rotation).

7. Constructing images from reflection axis based on an object.

8. Finding reflection axis from given two images.

9. Finding centre of circl es of various diameter.

10. Constructing circles using compass line.

11. Constructing tangenial line from a given point on the circumference.

12. Drawing line segment of 30°, 45°, 60°, 90" and much more.

13. Using as a protractor and constructing angles of any degree.

14. Constructing complete diagrams, drawings and designs.

The above operations, may be performed with the aid of at most only a ruler and one or two pencils.

The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description which proceeds, with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG 1A; FIG IB; FIG 1C; FIG ID, FIG IE, FIG IF shows the manner of using a conventional set square and ruler of prior art to draw reflected image.

FIG 2A; FIG 2B; FIG 2C, FIG 2D, FIG 2E, FIG 2F shows the manner of using a conventional ruler, compass & protractor of prior art to find and draw the centre of rotation;

FIG 3 A; FIG 3B; FIG 3C, FIG 3D shows the manner of using a conventional set square and ruler of prior art to find and draw an image based on 90° rotation;

Fig. 4a is a plan view of an example of the drafting instrument according to an embodiment the present invention of the invention;

Fig. 4b is a plan view of another example of the drafting instrument according to another embodiment the present invention of the invention;

Fig. Sa is an example of a line with interval points or compass line according to the present invention of the invention;

Fig. Sb is another example of a line with interval points or compass line according to the present invention of the invention;

Fig. 6 is a cross-section of the the drawing instrument adjacent to the vertex;

Fig. 7 is a cross-section the drawing instrument adjacent to the third side;

Fig. 8 is a cross-section view of the slit;

Fig. 9 shows a plan view of an example of the drafting instrument according to an embodiment the present invention of the invention;

Fig. 10 shows a plan view of another example of the drafting instrument according to an embodiment the present invention of the invention;

Fig. 11 shows a plan view of an example of the drafting instrument according to an embodiment the present invention of the invention;

Fig. 12 shows a plan view of an example of the drafting instrument according to an embodiment the present invention of the invention. DETAILED DESCRIPTION OF THE INVENTION

Fig.4a shows an example of the drawing instrument (10) according to an embodiment of the present invention. The drawing instrument comprises a first side (401) perpendicularly connected to a second side (402) forming a right angle; a third side (403) connected to the first side (401) and/or second side (402) forming a set or a set. of body for drawing a line and measuring a distance. Each of the sides (401, 402, 403) includes a straight edge. The edge may be beveled and marked with measurement or numeral intervals. As shown, a line with interval points (407) or a compass line is provided on the instrument. The line (407) may be disposed on any one of the sides (401 , 402, 403) for drawing a circle. In this example, the line (407) is disposed on the first side (401) of the instrument. The line is straight and parallel to the edge of the first side (401).

As shown in Fig.4a, the drawing instrument further comprising a first pivot hole (412) disposed at the connection point of the first side (401) and second side (402); and a second pivot hole (416) that is in line with the first pivot hole (412) and disposed on a mid-point of the third side (3).

Fig. 4b shows another example of the drawing instrument (20). The drawing instrument includes an internal slit (431) and at least an opening forming a fourth side (404), an internal curved edge (422) to act as protractor and a perpendicular ruler (440). The internal slit (431) is parallel to the third side (403). The protractor (422) is formed by a curvature which includes interval points for an angular measurement. The curvature may be a cut-out of semi-circle. A third pivot hole (415) disposed on a mid-point of the fourth side (404). The perpendicular ruler may be provided as an option on the instrument. The parallel ruler may extend from the fourth side following the perpendicular line (406) through the semi-circle cut and toward the internal (422). A fourth pivot hole (414) located in line and in between the first pivot hole (412) and the second pivot hole (416). Fig. 8 show a cross section of instrument at the slit (431). The edge of slit which is the edge of the fourth side (404) is bevel having a slanting surface (82). The other edge of the slit is curved (84).

Referring to Fig. 5a, the line with interval points includes a first point B with interval of 0.2cm and a second point F with interval of 0.3 cm from an initial or starting point A. The initial point A is preferably marked as '0' or '0.0' as shown in Fig. 5b. The series further includes a third point G with interval 0.5cm from the initial point A. The third point G may be measured with interval of 0.2cm from the second point F. The series further includes a fourth point H with interval of 1.0 cm from the initial point A. The series further includes a time accurately without lifting up the present invention or use other devices. Even when the starting point is lost, the reference is regained by using the perpendicular line (406) or 90 degree line of the protractor. In addition the first (401), second side (402), first pivot hole (412) and perpendicular line (406) permits the construction of image for 90 degree rotation and provide an improved facility to find centre of rotation based from two images of 90° rotation.

Referring to Fig. 9, the protractor may include two separate scales. The first scale (924) starts anticlockwise from the right hand side starting at the right upper edge (947) of the slit along the curved edge (422) until the left upper edge (948), while the second scale (923) starts clockwise from the left hand side starting at the left upper edge (948) until the right upper edge (947). The third pivot hole (415) acts as the centre point of the protractor, which will translate angular measurement and further cooperates with the fourth side (404) along its portion edges (919, 920) which aligns itself with respect to the circumference of circle to assist and to create tangenial line, to determine centre of circle and drawing images of different angular rotations. Said scales ranging from 3° to 177° with increment of 1 degree.

The instrument can be used as a protractor to measure and mark off selected degrees of a circle or an arc of a circle or any angle. The third pivot hole (415) of the instrument is placed on the point of circle or at the vertex or at the any point on the line. Then the arc or angle can be measured or marked, using a marking instrument to the nearest one degree along the curved edge (422) or line (923). The protractor is used in the following manner where to measure an angle formed by two lines, the portion edge (919,920) of the fourth side (404) is laid along one of the lines with the angle between the lines may then be read directly from the point of crossing of the second line with the protractor scale.

The body of the drawing instrument includes a first area (908) and a second area (909) which may be formed by a cut-out of a semi-cicle and/or divided by a perpendicular ruler (440).

The use and operation of the invention for drawing a line at an angle to the horizontal with the use of edge of the fourth side (404) will be discussed. The portion edge (919) of the fourth side (404) starts its zero mark from the third pivot hole (415) with increments, preferably of 1 mm. The portion edge (920) starts its zero mark from the third pivot hole (415) with numeral increments, preferably of 1mm . Constructing various angles and parallel lines whether vertical, horizontal or oblique and other lines can easily be constructed using correct fifth point I with interval of O.Scm from the fourth point H. The line with the interval points maybe parallel to any one of the sides. Fig. Sb show another example of the series. As shown in Fig. Sa and Fig. Sb, the interval points are in the form of holes. Preferabbly, the edges of the instrument are marked with numerical interval, scales for measurement. Fig. 6 and Fig. 7 show a hemispheric bumper (45) is integrally formed with the body of the instrument. One or more hemispheric bumpers (45) may be provided on the instrument. Raising the instrument above the drafting surface facilitates movement and eliminates smearing of ink under the instrument and its sides.

A line (406) perpendicular to the third side (3) may be provided as shown in Fig. 4a and Fig. 4b. This perpendicular line (406) together with the third side (403) allow users to find a centre of rotation from two images from unspecified angle of rotation, constructing images from reflection line, finding reflection axis from two images, and constructing parallel line. The line (406) extends from the vertex or the first pivot hole (412) to the second pivot hole (416).

The use and operation of the present invention for drawing images, obtaining centre of rotation or perpendicular line with the use of the first side (401), second side (402) and the first pivot hole (12) will be discussed. As shown in Fig. 4b and Fig. 9, preferabbly, the first pivot hole (412) acts as the starting zero for the first and second sides (401, 402). The second pivot hole (416) acts as the starting point for the third side (403) and the third pivot hole (415) acts as the starting point for the fourth side (404). Preferably, the edges of the instrument are marked with numerical intervals or scales for measurement. For example, the intervals of lmm may be provided.

The first relationship of the perpendicular line (406) correlates to the fourth side (404) at perpendicular angle 90°marked at the third pivot hole (415) which acts as the centre point of the protractor (422) and the fourth side (404). Perpendicular Line (406) also marks the centre point of the third hole (415) for the ruler on the fourth side (404) on which having uniform increment of measurement starting from zero from the third pivot hole (415) .

The second relationship of perpendicular line (406) connects and correlates to the third side (403) at perpendicular angle 90°and acts as the centre point of the third side (403) from the second pivot hole (416) which having uniform increment of measurement, starting from zero from the second pivot hole (416). All the two relationship are lined up and correlated to each other to permit users to obtain, locate and able to multitask at one specific techniques. The angle can be calculated and drawn by their relationship with the measurement values of the fourth side (404), pivot hole (416) and protractor scales (422, 923, 924).

The relationship of the fourth side (404) is correlated to protractor (422) while the third pivot hole (415) acts as the centre point of the protractor scales are lined up this way to permit users to obtain, locate and accurately multitask at one time which facilitates constructing image of any angle of rotation, finding centre of circles of various diameter and constructing tangenial line from a given point on the circumference of circle.

In use and operation of the invention for the third side (403), drawing images based on 180" degree rotation, obtaining mid-point of a line, obtaining centre of rotation for 180° degree drawings, and drawing parallel line will be discussed. The starting zero of the third side (403) is from the second pivot hole (416) corresponds to numeral increments of 1mm with full-scale ruler. The third side (403) also acts as a 90° line towards the perpendicular line (406).

The line with the interval points (407) act as a compass line which permits a user to precisely draw circle and the transparency of the instrument permits the user to readily view it with an adjustable radius in every one tenth of a centimetre within the range of scale. The adjustment of the radius is accomplished by adding the values in Line 407 for the desired radius or length value. By inserting pencils' point at respective value, a circle can be formed by moving one hand around and the other hand stationary which acts as the centre of circle. The compass line (407), has a centering hole for the insertion of a pin, sharp pencil, nails or other object similar character to act as pivot when the tool is used as a compass. As shown in Fig. Sa and 5b, the compass line (407) can be divided into a first section, a second section and a third section which corresponding to particular points or holes. As shown in Fig. Sa and Fig. Sb, the first section (610) comprising holes or points A, B, C, D, and E with an interval 0.2cm between the points. The second section (630) comprising holes or points A, F and G wherein F has an interval of 0.3 cm from point A and O has an interval of 0.5 from point A. The third section (607) includes a plurality of holes or points with an interval of 0.5 between the holes. As shown in Fig.5b, the tine (407) includes instrument the first section (610) that is positioned at a top and followed by the second section (630) and third section (607). As shown in Fig. 5a, the second section (630) is positioned at a top and followed by the first section (610) and the third section (607). Any one hole or point in the first section (610) and second section (630) can be used or marked as a centering point with another hole in the section be used as a second point for drawing a cirle. The radius of the circle may vary depending on the interval or hole of the second point. Pin, pencil or any pointed article can be used to mark the point through the hole. Any one hole in the third section (607) can be used as the second point for drawing a bigger cicle. The distance between the two points correspond to a radius value.

For example, as shown in Fig. 5b, if a pencil or pin is placed on the hole E as a pivot wherein point is marked 0.8 mat shows it is 0.8cm from the initial point A with 0.0 mark and another pencil is placed through the hole I with mark 1.5 that shows it is 1.5cm from the initial point A, rotation of the instrument by means of the pencil in the hole I will draw a circle having a 2.3 cm radius from the centre. This radius value 2.3 cm is accomplished by adding 1.5 cm and 0.8 cm from third section and first section respectively.

Each holes on compass line (407) is large enough to accommodate the point of a pencil, so that the device can mark on the writing material. The length of the compass line (407) may vary less or more, whichever demands and proves to be most convenient.

Fig. 10 shows another embodiment with a smaller size protractor (53) that may be extended from the fourth side (404). The curved edge of the protractor may start clockwise from the left hand side starting from the bottom left edge (54) until the bottom right edge (SS) of the slit. The formation of the protractor (S3) may replace the parallel ruler (440) where the third pivot hole (415) remains at the same position. The third pivot hole (415) acts as the centre point of the protractor, which will translate angular measurement and coorperates with the fourth side (404). The size of the smaller protractor (S3) may vary less or more, whichever proves to be most convenient.

An elongated portion of the fourth side (404) and third side (403) is shown by a portion (51) and a portion (52) in Fig. 11 with appropriate length. Another alternative embodiment of the invention is shown in Fig.12 without the compass line (407).