Projection teaching aid with semitransparent screen

Abstract

The utility model discloses a projection teaching aid with a semitransparent screen. The projection teaching aid comprises a height-adjustable light source and a projection device with the semitransparent screen. The height-adjustable light source is composed of a highlight flashlight and an X-shaped height adjusting support, and the height of the highlight flashlight can be adjusted by adjusting the X-shaped support. The projection device with the semitransparent screen is composed of a base, a side view screen, a main view screen, an L-shaped support and a transparent display support, space models such as points, lines, planes and bodies for teaching are placed on the transparent display support, screens of the side view screen and the main view screen are made of semitransparent materials to display and project, the screens are fixed through the movable L-shaped support, and the L-shaped support is fixed on the base. The side view screen and the main view screen are connected with the base through hinges, and can be put down on the base when not used. The principle is the same as that of shadow play, when light rays of the highlight flashlight penetrate through the space model, projection is generated on the semitransparent screen, and the clear outline of the space model can be seen on the back faces of the side view screen and the main view screen.

Description

Technical Field

[0001] This utility model relates to teaching aids for solid geometry and mechanical drawing, which project the outline of a spatial model to students during teaching. Background Technology

[0002] Because students' spatial reasoning abilities require specialized training to mature, teachers often struggle to understand the spatial relationships between geometric elements such as points, lines, planes, and solids in high school solid geometry and university mechanical drawing. This is largely due to students' immature spatial reasoning skills, and some students find the subject particularly difficult. Therefore, providing a three-dimensional projection aid that directly displays the relative positions of geometric elements on a projection screen is essential for students to understand the shapes and spatial relationships of geometric elements.

[0003] Existing geometric projection teaching aids on the market are relatively outdated. They lack a light source for projection and simply draw the outline of a fixed spatial model on the main view, side view, and top view projection planes. The shape and position of the spatial model cannot be changed. Changing the spatial model requires a new geometric projection teaching aid, which has obvious drawbacks. Summary of the Invention

[0004] Therefore, this utility model provides a projection teaching aid with a light source and a semi-transparent screen. Utilizing the projection principle of shadow puppetry, it can display the projection of spatial models in real-time, intuitively, dynamically, or statically. During teaching, teachers can use spatial models of any shape for real-time dynamic projection display, placing them at any angle on a transparent display stand. Light will project the outer contour of the spatial model onto the main view, side view, and top view projection surfaces in real time. If the spatial model has a frame structure, the internal frame lines and the frame lines on the back of the spatial model can also be projected.

[0005] This type of projection teaching aid is seen Figure 1 As shown, it consists of two parts: a height-adjustable light source and a projection device with a semi-transparent screen. The relative positions of the two parts can be adjusted according to teaching needs. The height-adjustable light source consists of a high-intensity flashlight 7 and an X-shaped bracket 6. The projection device with a semi-transparent screen consists of a base 1, a main projection surface 2, a side projection surface 3, an L-shaped bracket 4, and a transparent display bracket 5. Their structures are described in detail below.

[0006] Projection devices with semi-transparent screens are shown below. Figure 2 It consists of a base 1, a main projection surface 2, a side projection surface 3, an L-shaped bracket 4, and a transparent display bracket 5.

[0007] Figure 2The transparent display stand 5 is made of transparent plastic or glass, and is inverted U-shaped. It is placed on the base 1 without being fixed. Various spatial models of points, lines, surfaces, and volumes are placed on top of the transparent display stand 5 according to teaching needs. It is essential to ensure that the spatial models are within the illumination range of a strong flashlight.

[0008] The material structure of the base 1 is shown in Figure 4. It consists of a flat panel 11 and feet 12. The flat panel 11 is made of wood or plastic, and four rubber feet 12 are fixed to the bottom with screws. Holes can be drilled on the sides and bottom of the flat panel 11 to fix the hinges 24 on the side screen 2 and the main screen 3 with nails or screws.

[0009] Figure 2 The side-view screen 2 and the main-view screen 3 have the same structure, only with slight differences in size. Here, we will only introduce the structure of the side-view screen 2, which is shown in Figure 3.

[0010] Figure 3 The center-side viewing screen 2 consists of a semi-transparent screen 21, four plastic clips 22, a rectangular wire 23, and two hinges 24. The rectangular wire 23 is made by bending a single wire and welding the seams to form a closed rectangle. The semi-transparent screen 21 is made of semi-transparent fabric or plastic film with a light transmittance between 30% and 70%. It is sewn or glued to the four sides of the rectangular wire 23. The top edge of the semi-transparent screen 21 is fixed to the ends of the sewn seams of the rectangular wire 23 using plastic clips 22. An interference fit is used between the plastic clips 22 and the rectangular wire 23 to prevent the fabric from slipping. The bottom edge of the semi-transparent screen 21 is fixed to the ends of the sewn seams of the rectangular wire 23 using both plastic clips 22 and hinges 24.

[0011] Figure 3 The hinge 24 on the side screen 2 is fixed to the side and bottom of the base 1 by nails or screws, so that the side screen 2 can be folded down on the base 1 when not in use. The main screen 3 is also folded down on the base 1 in the same way when not in use.

[0012] The side view screen 2 and the main view screen 3 are fixed together by a movable L-shaped bracket 4. The structure of the L-shaped bracket 4 is shown in [details omitted]. Figure 5 It consists of two mutually perpendicular, semi-circular groove-shaped straight bars. When in use, the straight bar 1 is elastically clamped into the plastic sleeve 22 of the side screen 2 and the main screen 3. When not in use, the L-shaped bracket 4 is forcefully removed from the plastic sleeve 22, and the side screen 2 and the main screen 3 can be laid down on the base 1 respectively.

[0013] The high-powered flashlight 7 is a commercially available high-powered flashlight, consisting of a round flashlight and a handle, placed above the adjustable X-shaped bracket 6. Depending on the height of the displayed spatial model, the height of the high-powered flashlight can be adjusted by changing the length of the rope at the bottom of the X-shaped bracket 6, causing the X-shaped bracket 6 to rotate around its center line, thus ensuring the light shines directly onto the displayed spatial model and projects its entire outline.

[0014] The shape of the X-shaped bracket 6 is shown in the figure. Figure 6 As shown, it consists of two left-side brackets 62, two right-side brackets 61, two pins 63, two crossbars 64 below, a rope 68 below, semicircular rings 65 and 66 above, and four plastic clips 67.

[0015] Figure 6 The middle part of the left side bracket 62 and the right side bracket 61 is connected by a pin 63, and the height of the bracket can be changed by rotating around the center line of the pin 63.

[0016] Figure 6 The lower parts of the two left-side supports 62 are connected by a crossbar 64, and the lower parts of the two right-side supports 62 are also connected by another crossbar 64. There are holes in the middle of the two crossbars 64, and ropes 68 pass through these two holes. By adjusting the length of the ropes 68, the distance between the two crossbars 64 is changed, thereby adjusting the height of the entire support.

[0017] Figure 6 The upper parts of the two left-side brackets 62 are connected by semicircular rings 65. The two ends of the semicircular rings 65 are respectively press-fitted with two plastic sleeves 67 to prevent the left-side brackets 62 from detaching from the semicircular rings 65. The upper parts of the two right-side brackets 61 are also connected by semicircular rings 66. The two ends of the semicircular rings 66 are respectively press-fitted with two plastic sleeves 67 to prevent the right-side brackets 62 from detaching from the semicircular rings 66. The radii of the semicircular rings 65 and 66 are adapted to the outer circumference of the high-powered flashlight 7 for holding the flashlight 7. Attached Figure Description

[0018] Figure 1 The diagram shows the overall structure of this utility model, including: 1. Base; 2. Side screen; 3. Main screen; 4. L-shaped fixing strip; 5. Transparent display rack; 6. X-shaped bracket; 7. High-powered flashlight.

[0019] Figure 2 This is a schematic diagram of the projection device for the semi-transparent screen of this utility model. The reference numerals are... Figure 1 same.

[0020] Figure 3This is a schematic diagram of the side view screen of this utility model. In the figure: 1. Semi-transparent screen 21; 2. Plastic sleeve 22; 3. Rectangular wire 23; 4. Hinge 24.

[0021] Figure 4 This is a schematic diagram of the base of this utility model. In the figure: 1. Flat plate 11; 2. Foot pad 12.

[0022] Figure 5 This is a schematic diagram of the structure of the L-shaped fixing strip of this utility model.

[0023] Figure 6 The diagram shows the structure of the X-shaped bracket of this utility model. In the diagram: 1. Left bracket 62; 2. Right bracket 61; 3. Pin 63; 4. Crossbar 64; 5. Rope 68; 6. Semicircular ring 65; 7. Semicircular ring 66; 8. Plastic sleeve 67. Detailed Implementation

[0024] This utility model is based on the same principle as shadow puppetry. When using it, teachers place the spatial model they use according to their teaching needs on the transparent display stand 5 and arrange it according to the required projection angle and position.

[0025] When it is necessary to project the spatial model onto the main screen, place the high-powered flashlight 7 on the X-shaped bracket 6, with both facing the spatial model and the main projection screen 3. Then adjust the height of the X-shaped bracket so that the light from the high-powered flashlight 7 passes through the spatial model and projects onto the semi-transparent screen of the main projection screen 3. Students can see the clear outline of the spatial model on the back of the main projection screen 3.

[0026] If the teaching requires projecting the outline of the spatial model onto both the side screen 2 and the main screen projection 3 simultaneously, then two sets of high-powered flashlights 7 and X-shaped brackets 6 are needed, facing the side screen 2 and the main screen projection 3 respectively, to project simultaneously.

[0027] If the teaching requires simultaneously projecting the outline of the spatial model onto the main screen projector 3 and projecting a top view of the spatial model onto the base 1 (this is less common), a set of high-powered flashlights 7 and an X-shaped bracket 6 are used to project the model onto the main screen projector 3. At the same time, the teacher holds another high-powered flashlight 7 above the spatial model and shines it downwards onto the base 1. The outline of the spatial model appears on the base 1, and students can see the projected outline through the transparent display stand 5.

[0028] Similarly, if projections are to be generated simultaneously on the front view, side view, and top view, three high-powered flashlights 7 and two X-shaped brackets 6 are required.

[0029] If the spatial model uses a frame structure (available on the market), the internal frame lines and the rear frame lines of the spatial model can also be projected.

[0030] After the lesson is completed, the projection device needs to be folded. Remove the L-shaped fixing strip 4 forcefully, and then lay down the side screen 2 and the main screen projection 3 in sequence, stacking them on the base 1. Folding the side screen 2 and the main screen projection 3 in this way makes them easy to move and store.

Claims

1. A kind of translucent screen projection teaching aid, by base (1), main view projection surface (2), side view projection surface (3), L-shaped support (4), transparent display support (5), X-shaped support (6), strong light flashlight (7) jointly constitute, it is characterized in that, The screen of the front projection surface (2) and the side projection surface (3) is made of translucent material, including cloth and plastic film, and the light transmittance of the material is between 30-70%.

2. The projection teaching aid of claim 1, wherein, The front projection surface (2) and the side projection surface (3) are connected with the base (1) by hinges, and when projection is needed, the base (1), the front projection surface (2) and the side projection surface (3) are kept perpendicular to each other, and when projection is not needed, the front projection surface (2) and the side projection surface (3) can be folded and laid on the base (1) in turn, which is convenient for moving and storing.

3. A translucent screen projection teaching aid according to claim 2, wherein, When projection is used, the front projection surface (2) and the side projection surface (3) are perpendicular to the base (1) after being turned from the folded position, and the two edges of the L-shaped bracket (4) are elastically clamped on the upper part of the front projection surface (2) and the side projection surface (3) respectively, fixing their positions; when projection is not used, the L-shaped bracket (4) can be pulled out from the upper part of the front projection surface (2) and the side projection surface (3) by force, and the front projection surface (2) and the side projection surface (3) can be folded in turn.

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