Compass for easy observation of radius degree

Abstract

The utility model relates to the technical field of drawing tools, concretely is compass convenient for observing radius degree, including support leg and movable leg, the upper portion one side of movable leg is installed with the scale board of arc shape with scale line, the support leg is close to the scale board department and is opened with scale board sliding hole, the end of scale board passes through scale board sliding hole, the support leg is close to the scale board department and is installed with magnifying glass, the bottom of support leg is installed with fixed needle, the bottom of movable leg is installed with lead core, the bottom outside of support leg is installed with protection cover. In the compass convenient for observing radius degree, the arc scale board of movable leg upper portion one side is installed with scale line, and the end passes through the scale board sliding hole of support leg, and is installed with the magnifying glass on the support leg close to the scale board department, when adjusting the radius of compass, the user can clearly observe the scale on the scale board through the magnifying glass directly, need not help additional auxiliary tool, greatly simplified the observation and the determination process of radius degree.

Description

Technical Field

[0001] This utility model relates to the field of drawing tools, specifically to a compass that facilitates the observation of radius degrees. Background Technology

[0002] Before introducing compasses, which facilitate the observation of radius measurements, let's first review the development of compasses in the field of drafting tools. As a commonly used tool in mathematics and drafting, the compass plays a crucial role in ruler-and-compass constructions, used to draw circles or chords. Traditional compasses typically employ an A-frame structure, consisting of two hinged legs. One leg holds a positioning pin, while the other holds a drawing tool such as a pen lead. Circles are drawn by rotating around the positioning pin. However, in practical use, this type of traditional compass reveals several problems. For example, determining the radius of an arc often requires additional tools such as a ruler, making the operation cumbersome, reducing drafting efficiency, and easily leading to drawing errors due to multiple measurements.

[0003] To address these issues, numerous explorations and innovations have been undertaken in related fields. For example, patent application number CN205416884U discloses a compass. When using this compass, the positioning screw must first be rotated counterclockwise, then the radius scale must be rotated around the fixing cap until the adjustment groove on the radius scale aligns with the hole on the positioning screw. The positioning screw is then rotated to fix it. Finally, based on the determined radius, the relative positions of the support rod and the rotating rod are adjusted according to the radius scale. After adjusting to the desired radius, the positioning screw is fixed again before drawing can begin. While this compass can draw circles of a set radius to some extent, its operation is extremely complex and alters the original simple structure of the compass, increasing the user's operational difficulty and learning curve.

[0004] For example, patent application CN204726101 proposes a safe and portable compass with a precisely adjustable radius scale, consisting of a ruler, a rotary knob, a needle, a pen cap, a pen refill, and a slider. It moves the compass by sliding the slider within the ruler, and the compass can rotate relative to the slider. However, determining the radius scale requires observing the slider's movement on the ruler and the scale markings at specific points, which is not intuitive and inefficient for drafting work requiring frequent and precise radius adjustments.

[0005] Looking at patent application number CN204774253, the disclosed compass includes a ruler, a fixed foot, and a movable foot, attempting to solve the problem of radius measurement and determination when drawing a circle through a specific connection method. However, in practical use, due to its relatively complex structure, adjusting the radius requires a series of operations such as sliding the L-shaped movable foot and tightening or loosening bolts. Different diameter ranges correspond to different operating methods, making the operation inconvenient for users, easily confusing the steps, and consequently affecting drawing efficiency and accuracy. Utility Model Content

[0006] The purpose of this invention is to provide a compass that facilitates the observation of radius measurements, thereby addressing the numerous problems that traditional compasses exhibit in practical use, as mentioned in the background section. For example, determining the radius of an arc often requires the use of additional tools such as rulers, making the operation cumbersome, reducing drafting efficiency, and easily leading to drawing errors due to multiple measurements.

[0007] To achieve the above objectives, this utility model provides a compass for easy observation of radius measurements, comprising a support leg and a movable leg. An arc-shaped scale plate with graduation lines is installed on one side of the upper part of the movable leg. A sliding hole for the scale plate is provided on the support leg near the scale plate, and the end of the scale plate passes through the sliding hole. A magnifying glass is installed on the support leg near the scale plate. A fixing pin is installed at the bottom of the support leg. A pen refill is installed at the bottom of the movable leg. A protective cover is installed on the outer side of the bottom of the support leg.

[0008] This feature includes an arc-shaped scale plate with graduated lines mounted on one side of the upper part of the movable leg. Its end passes through a sliding hole in the scale plate of the supporting leg. By changing the angle between the movable leg and the supporting leg, the scale plate moves, thus changing the radius scale. A magnifying glass on the supporting leg magnifies the scale plate's graduations for precise observation. A fixing pin is used to fix the center point, the pen refill is used to draw the circumference, and a protective cap protects both the fixing pin and the pen refill.

[0009] Preferably, the top ends of the support leg and the movable leg are rotatably connected by a turntable, the top of the turntable is equipped with a handle, and a locking knob is installed on one side of the turntable.

[0010] This design features a support leg and a movable leg connected by a turntable. The rotation of the turntable allows for changes in the angle between the two legs, thereby adjusting the compass radius. The handle provides a convenient grip for the user to operate the compass. The locking knob secures the relative position of the movable leg and the support leg, preventing changes in the radius during drawing.

[0011] Preferably, a protective cover storage groove is provided on the bottom inner side of the support leg, and the upper end of the protective cover is rotatably connected to the bottom pin hole of the support leg through a pin. The protective cover can be flipped up and folded into the protective cover storage groove.

[0012] This feature allows the protective cover to be rotated and connected to the pin hole at the bottom of the support leg via a pin, using the lever principle to achieve the flipping of the protective cover; the protective cover storage slot on the inner side of the bottom of the support leg provides storage space for the protective cover, which can be flipped up and folded into storage when not in use.

[0013] Preferably, the bottom of the movable leg has an arc-shaped groove near the storage slot of the protective cover.

[0014] This feature allows the curved groove at the bottom of the movable leg to match the shape of the outer side of the protective cover when folded and stored, preventing pressure damage between the bottom of the movable leg and the protective cover during drawing.

[0015] Preferably, the protective cover includes a connecting rod, with a circular cover installed at the lower end of the connecting rod. The circular cover has grooves on both sides for securing the needle and pen refill, respectively.

[0016] The circular cover with protective caps has grooves on both sides that match the shapes of the retaining pin and the pen refill, respectively. By wrapping and limiting the design, it provides physical protection for the retaining pin and pen refill when the compass is not in use, preventing damage from impacts, pressure, or other factors.

[0017] Preferably, the upper part of the support leg is provided with a magnifying glass mounting port, and the magnifying glass is installed in the magnifying glass mounting port. The magnifying glass is a transparent plastic structure with a hemispherical protrusion.

[0018] This feature includes a magnifying glass installed in the magnifying glass mounting port on the upper part of the support leg. Its hemispherical protrusion of transparent plastic structure uses the principle of optical refraction to magnify the scale on the scale plate, allowing users to observe the scale details more clearly.

[0019] Preferably, a clamping knob is installed on one side of the bottom of the movable leg, and the clamping knob clamps the pen refill against the inner bottom of the movable leg by turning it.

[0020] This setting features a locking knob connected to the movable leg via a threaded structure. When the locking knob is turned, the transmission and compression principle of the thread is used to press the pen refill tightly against the inner side of the bottom of the movable leg, thus achieving a fixed installation of the pen refill.

[0021] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0022] This compass, which facilitates the observation of radius measurements, features an arc-shaped scale plate with graduations mounted on one side of the upper part of the movable leg. The end of the scale plate passes through a sliding hole in the scale plate on the supporting leg. With the help of a magnifying glass mounted on the supporting leg near the scale plate, the user can clearly observe the graduations on the scale plate directly through the magnifying glass when adjusting the compass radius, without the need for additional auxiliary tools. This greatly simplifies the process of observing and determining the radius measurements and significantly improves the accuracy and efficiency of drawing.

[0023] The protective cover installed on the outer bottom of the support leg is rotatably connected to the pin hole at the bottom of the support leg via a pin, and can be flipped up and folded into the protective cover storage slot. At the same time, the grooves on both sides of the circular cover of the protective cover protect the fixing pin and the pen refill respectively, preventing accidental damage to the fixing pin and the pen refill when not in use, and facilitating the storage and carrying of the compass, thereby improving the safety and convenience of using the compass. Attached Figure Description

[0024] Figure 1 This is one of the overall structural schematic diagrams of this utility model;

[0025] Figure 2 This is the second schematic diagram of the overall structure of this utility model;

[0026] Figure 3 This is a schematic diagram of the support leg in this utility model;

[0027] The meanings of the labels in the diagram are as follows:

[0028] 1. Support leg; 11. Magnifying glass mounting port; 12. Scale plate sliding hole; 13. Protective cover storage slot; 14. Fixing pin; 15. Pin hole; 2. Movable leg; 21. Clamping knob; 22. Pen refill; 3. Scale plate; 4. Magnifying glass; 5. Protective cover; 6. Turntable; 7. Handle end; 8. Locking knob. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0030] This utility model provides a compass for easy observation of radius measurements, such as... Figures 1-3As shown, it includes a support leg 1 and a movable leg 2. An arc-shaped scale plate 3 with graduation lines is installed on one side of the upper part of the movable leg 2. A scale plate sliding hole 12 is opened on the support leg 1 near the scale plate 3. The end of the scale plate 3 passes through the scale plate sliding hole 12. A magnifying glass 4 is installed on the support leg 1 near the scale plate 3. A fixing pin 14 is installed at the bottom of the support leg 1. A pen refill 22 is installed at the bottom of the movable leg 2. A protective cover 5 is installed on the outer side of the bottom of the support leg 1.

[0031] An arc-shaped scale plate 3 with graduation lines is installed on one side of the upper part of the movable leg 2. Its end passes through the scale plate sliding hole 12 of the support leg 1. By changing the angle between the movable leg 2 and the support leg 1, the scale plate 3 is moved, realizing the change of radius scale. A magnifying glass 4 installed on the support leg 1 near the scale plate 3 can magnify the scale of the scale plate 3 for easy and accurate observation. The fixing pin 14 at the bottom of the support leg 1 is used to fix the center of the circle. The pen lead 22 at the bottom of the movable leg 2 is used to draw the circumference. The protective cover 5 on the outer side of the bottom of the support leg 1 can protect the fixing pin 14 and the pen lead 22. Without the need for other measuring tools, the radius of the compass can be observed and adjusted intuitively and accurately, improving the drawing accuracy and efficiency. The protective cover 5 enhances the safety and portability of the compass and prevents accidental damage to the fixing pin 14 and the pen lead 22.

[0032] In this embodiment, the top ends of the support leg 1 and the movable leg 2 are rotatably connected by a turntable 6. A handle end 7 is installed on the top of the turntable 6, and a locking knob 8 is installed on one side of the turntable 6.

[0033] The supporting leg 1 and the movable leg 2 are rotatably connected by a turntable 6. The rotation of the turntable 6 allows for changes in the angle between the two legs, thereby adjusting the compass radius. A handle 7 on the top of the turntable 6 provides a convenient grip for the user to operate the compass. A locking knob 8 on one side of the turntable 6 secures the relative position of the movable leg 2 and the supporting leg 1, preventing radius changes during drawing. This makes compass operation more flexible and convenient, allowing users to easily adjust to the desired radius and maintain radius stability during drawing, ensuring drawing quality.

[0034] Specifically, a protective cover storage groove 13 is provided on the bottom inner side of the support leg 1. The upper end of the protective cover 5 is rotatably connected to the bottom pin hole 15 of the support leg 1 through a pin. The protective cover 5 can be flipped up and folded into the protective cover storage groove 13.

[0035] The protective cover 5 is rotatably connected to the pin hole 15 at the bottom of the support leg 1 via a pin, and the protective cover 5 is flipped over using the lever principle. The protective cover storage groove 13 set on the inner side of the bottom of the support leg 1 provides storage space for the protective cover 5. When the protective cover 5 is not in use, it can be flipped up and folded into it for storage. The protective cover 5 can be stored away when not in use to avoid taking up extra space, making the compass more compact and easy to store and carry. At the same time, the protective cover 5 can be quickly unfolded for use when needed to protect the fixing pin 14 and the pen refill 22.

[0036] Furthermore, an arc-shaped groove is provided at the bottom of the movable leg 2 near the protective cover storage slot 13 to prevent the movable leg 2 from squeezing and damaging the protective cover 5 during drawing.

[0037] The curved groove at the bottom of the movable leg 2, near the protective cover storage slot 13, matches the shape of the outer side of the folded protective cover 5. This fit creates a locking force, firmly securing the protective cover 5 in its stored position and preventing accidental unfolding. This ensures the protective cover 5 remains stable in its folded state, preventing it from opening due to shaking or other reasons, thus improving the reliability of compass storage and further enhancing its portability and safety.

[0038] Furthermore, the protective cover 5 includes a connecting rod, with a circular cover installed at the lower end of the connecting rod. The circular cover has grooves on both sides for securing the needle 14 and the pen refill 22, respectively.

[0039] The circular cap installed at the lower end of the connecting rod of the protective cover 5 has grooves on both sides that match the shapes of the fixing pin 14 and the pen refill 22. Through wrapping and limiting, it provides physical protection for the fixing pin 14 and the pen refill 22 when the compass is not in use, preventing damage from impacts, pressure, etc. This effectively protects the fixing pin 14 and the pen refill 22, extending the compass's lifespan; it also reduces the risk of the user being pricked by the fixing pin 14, enhancing the safety of compass use.

[0040] Furthermore, the upper part of the support leg 1 is provided with a magnifying glass mounting port 11, and the magnifying glass 4 is installed in the magnifying glass mounting port 11. The magnifying glass 4 is a transparent plastic structure with a hemispherical protrusion.

[0041] The magnifying glass 4, housed within the magnifying glass mounting port 11 on the upper part of the support leg 1, utilizes the principle of optical refraction through its hemispherical, convex transparent plastic structure to magnify the scale markings on the scale plate 3, allowing the user to observe scale details more clearly. Even with small scale markings, the user can accurately read the scale values, thereby precisely adjusting the compass radius and greatly improving the accuracy of radius measurement observation, ensuring the creation of high-precision graphics.

[0042] Furthermore, a clamping knob 21 is installed on one side of the bottom of the movable leg 2. The clamping knob 21 clamps the pen refill 22 against the inner side of the bottom of the movable leg 2 by turning it.

[0043] A locking knob 21, installed on one side of the bottom of the movable leg 2, is connected to the movable leg 2 via a threaded structure. When the locking knob 21 is turned, the transmission and compression principle of the thread is used to firmly press the pen refill 22 against the inner side of the bottom of the movable leg 2, thus fixing the pen refill 22 in place. This ensures that the pen refill 22 will not loosen or fall off during drawing, making the drawing lines continuous and stable, improving drawing quality and efficiency, and also facilitating the replacement of different types of pen refills 22.

[0044] When using this compass that facilitates the observation of radius measurements, the protective cover 5 is first flipped upwards when the compass is needed. The protective cover 5 is rotatably connected to the pin hole 15 at the bottom of the support leg 1 via a pin. Based on the lever principle, the user can easily flip it upwards and place it into the protective cover storage groove 13. At this time, the grooves on both sides of the lower circular cover of the protective cover 5 no longer cover the fixing pin 14 and pen refill 22, preparing for subsequent drawing operations.

[0045] When adjusting the compass radius, hold the handle end 7 at the top of the turntable 6 and loosen the locking knob 8 on one side of the turntable 6 to release the fixation of the relative position of the movable leg 2 and the support leg 1. Then, rotate the movable leg 2 around the turntable 6 to change its angle with the support leg 1. During this process, the arc-shaped scale plate 3 installed on the upper side of the movable leg 2 moves accordingly. Since the end of the scale plate 3 passes through the scale plate sliding hole 12 of the support leg 1, the scale plate 3 can slide along a specific path, and the change in its scale value corresponds to the change in the compass radius. The user can use the magnifying glass 4 installed on the support leg 1 near the scale plate 3 to clearly magnify and observe the scale lines on the scale plate 3 using the optical refraction principle of the hemispherical convex transparent plastic structure of the magnifying glass 4, thereby intuitively and accurately adjusting the compass radius to the required value. After adjustment, tighten the locking knob 8 to fix the relative position of the movable leg 2 and the support leg 1, ensuring that the radius remains stable during drawing.

[0046] Press the fixing pin 14 at the bottom of the support leg 1 vertically onto the drawing to determine the center position. The sharp head of the fixing pin 14 firmly embeds itself into the paper, ensuring a stable fixation of the center. Next, using the fixing pin 14 as the center, hold the handle end 7 and rotate the movable leg 2 around the center, causing the pen lead 22 mounted at the bottom of the movable leg 2 to draw a circle on the drawing. Because the pen lead 22 is tightly pressed against the inner bottom of the movable leg 2 by the tightening knob 21, and fixed using the transmission and compression principle of the thread, the pen lead 22 will not loosen or fall off during the rotational drawing process, ensuring continuous and smooth lines and completing the drawing of the desired circular shape.

[0047] After drawing, remove the compass from the drawing. Hold the handle end 7 again, loosen the locking knob 8, and adjust the angle between the movable leg 2 and the support leg 1 to make the compass more compact. Then tighten the locking knob 8 to secure it. Next, flip the protective cover 5 downwards so that it emerges from the storage slot 13 at the bottom of the support leg 1. The grooves on both sides of the circular cover at the bottom of the protective cover 5 respectively enclose the fixing pin 14 and the pen refill 22, providing physical protection for them and preventing damage from collisions or squeezing during storage and transport, making them convenient for future use.

[0048] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A compass for easy observation of radius measurements, comprising a support leg (1) and a movable leg (2), characterized in that: An arc-shaped scale plate (3) with graduation lines is installed on one side of the upper part of the movable leg (2). A scale plate sliding hole (12) is opened on the support leg (1) near the scale plate (3). The end of the scale plate (3) passes through the scale plate sliding hole (12). A magnifying glass (4) is installed on the support leg (1) near the scale plate (3). A fixing pin (14) is installed at the bottom of the support leg (1). A pen refill (22) is installed at the bottom of the movable leg (2). A protective cover (5) is installed on the outer side of the bottom of the support leg (1).

2. The compass for facilitating the observation of radius measurements according to claim 1, characterized in that: The top ends of the supporting leg (1) and the movable leg (2) are rotatably connected by a turntable (6). A handle end (7) is installed on the top of the turntable (6), and a locking knob (8) is installed on one side of the turntable (6).

3. The compass for facilitating the observation of radius measurements according to claim 1, characterized in that: The bottom inner side of the support leg (1) is provided with a protective cover storage groove (13). The upper end of the protective cover (5) is rotatably connected to the bottom pin hole (15) of the support leg (1) through a pin. The protective cover (5) can be flipped up and folded into the protective cover storage groove (13).

4. The compass for facilitating the observation of radius measurements according to claim 3, characterized in that: An arc-shaped groove is provided at the bottom of the movable leg (2) near the protective cover storage slot (13).

5. The compass for facilitating the observation of radius measurements according to claim 3, characterized in that: The protective cover (5) includes a connecting rod, and a circular cover is installed at the lower end of the connecting rod. The circular cover has grooves on both sides, which are used to fix the needle (14) and the pen refill (22) for protection.

6. The compass for facilitating the observation of radius measurements according to claim 1, characterized in that: The upper part of the support leg (1) is provided with a magnifying glass mounting port (11), and the magnifying glass (4) is set in the magnifying glass mounting port (11). The magnifying glass (4) is a transparent plastic structure with a hemispherical protrusion.

7. The compass for facilitating the observation of radius measurements according to claim 1, characterized in that: A clamping knob (21) is installed on one side of the bottom of the movable leg (2). The clamping knob (21) clamps the pen refill (22) against the inner side of the bottom of the movable leg (2) by turning it.

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