CN108922333A - Describe sinusoidal teaching demonstration device and application method - Google Patents

Abstract

The invention relates to a teaching and demonstration device for drawing a sine curve and a method for using it, comprising a magnetic whiteboard, a horizontal through slot is placed horizontally on the magnetic whiteboard, a rotating shaft perpendicular to the magnetic whiteboard is passed through the horizontal through slot, and a disc is arranged at the front end of the rotating shaft. A number of paintbrush jacks are set at intervals along the radial direction on the disk, a gear is set at the rear end of the rotating shaft, and a horizontal rack meshing with the gear is set on the rear side of the magnetic whiteboard above the gear, and the horizontal rack is fixed on the lower end surface of the horizontal module bar. The bar is magnetically fixed to the rear side of the magnetic whiteboard. Insert the paintbrush into any jack on the disk. The traction shaft moves horizontally or rotates the disk or gear in the horizontal through groove. The horizontal rack and gear are meshed for transmission. The rotating shaft drives the disc to rotate, so that the trajectory of any particle in the circular motion can be intuitively used, and the sine wave curve can be explained and drawn on the disc on the front side of the magnetic whiteboard with a brush. This device is easy to operate and helps students understand the sine wave Curve-related knowledge for learning and understanding.

Description

Teaching Demonstration Device and Application Method for Drawing Sinusoidal Curve

technical field

The invention relates to a teaching demonstration device for drawing a sinusoidal curve and a use method thereof.

Background technique

At present, in mathematics teaching, the teaching demonstration of sine curves has always been a difficult problem. Teachers cannot demonstrate on the blackboard, but can only do simple drawing by hand. The drawn sine curves are not regular. Therefore, students are not sure how to draw sine curves. It has been difficult to understand and master.

Therefore, based on the above-mentioned defects, in the field of teaching instruments, there is still a demand for research and improvement on devices used to demonstrate sinusoidal curves in new teaching, which is also a research focus and focus in the field of teaching instruments.

Contents of the invention

The invention provides a teaching demonstration device and a using method for drawing a sinusoidal curve.

The solution adopted by the present invention to solve the technical problem is that a teaching and demonstration device for depicting a sinusoidal curve includes a magnetic whiteboard, a horizontal through groove is placed horizontally in the middle of the magnetic whiteboard, and a rotating shaft perpendicular to the magnetic whiteboard is penetrated in the horizontal through groove, and the rotating shaft can Move horizontally in the horizontal through groove, the front end of the rotating shaft is provided with a disk, on the disk radially arranged from the inside to the outside, a number of brush sockets are provided, the rear end of the rotating shaft is provided with a gear, and the rear side of the magnetic whiteboard is provided above the gear. The horizontal racks are engaged, and the horizontal racks are fixed on the lower end surface of the horizontal module bar, and the module bar is magnetically fixed to the rear side of the magnetic whiteboard. The distance between the gear and the disc is equal to the thickness of the magnetic whiteboard. The horizontal rack and the module bar are locked by screws or the horizontal rack and the module bar are integrated. The horizontal rack is parallel to the horizontal slot, and the horizontal rack is connected to the horizontal slot. The distance between the slots is the radius of the gear.

Further, two protrusions are symmetrically arranged on the left and right sides of the front side of the module bar, and two vertical chutes for accommodating the protrusions are arranged symmetrically on the left and right sides of the rear side of the magnetic whiteboard. The hole runs through the protrusion, the module strip and is perpendicular to the magnetic whiteboard, and a locking screw is arranged in the locking screw hole, and the module strip is locked on the magnetic whiteboard through the locking screw.

Further, the module bar is made of strong magnetic material; or the contact surface between the module bar and the magnetic whiteboard is embedded with a magnet.

Further, a rolling bearing is arranged between the rotating shaft and the horizontal through groove, and the rolling bearing is installed on the rotating shaft.

Further, the disc and the gear are connected and locked with the rotating shaft through locking nails.

Further, there are multiple gears with different diameters, and only one gear is installed at the rear end of the rotating shaft.

Further, the magnetic whiteboard is installed on the whiteboard support, and the whiteboard support includes a base, vertical bars are symmetrically arranged on the left and right sides of the base, a fixed block is arranged on the inner side of the upper end of the vertical bar, a shaft hole is placed horizontally on the upper end of the vertical bar, and the middle part of the inner side of the fixed block is arranged To accommodate the notch of the whiteboard frame, the front and rear sides of the fixed block are provided with screw holes A, and the screw hole A is pierced with a locking screw A, the inner end of the locking screw A is against the whiteboard, and the outer end of the locking screw A is provided with a handwheel A , the middle part of the outer surface of the fixed block is provided with a shaft part, the shaft part is accommodated in the shaft hole and rotatably matched with the shaft hole, a screw hole B is arranged in the shaft part along the axial direction, and a locking screw B is arranged in the screw hole B, and the locking screw B The inner end is located in the screw hole B, and the outer end of the locking screw B is provided with a handwheel B.

Further, the lower part of the base is provided with universal wheels with foot brakes.

Further, the inner end of the locking screw A is provided with a rubber pad.

A method for using a teaching demonstration device for depicting a sinusoidal curve, comprising the following steps:

(1) Move the rotating shaft to the left end of the horizontal chute;

(2) Insert the paintbrush into any paintbrush socket on the disc;

(3) Move the module bar up and down to make the horizontal rack mesh with the gear;

(4) The traction shaft moves horizontally or rotates the disc or gear in the horizontal through groove, and the horizontal rack and gear are engaged for transmission, so that the disc is driven to rotate through the shaft, and the brush on the disc draws a sine wave on the front side of the magnetic whiteboard curve.

Compared with the prior art, the invention has the following beneficial effects: the structure is simple, the design is reasonable, the operation is convenient, and it is helpful for students to learn and understand the knowledge related to sinusoidal curves.

Description of drawings

Below in conjunction with accompanying drawing, the patent of the present invention is further described.

Fig. 1 is a structural schematic diagram one of the present invention;

Fig. 2 is a structural schematic diagram two of the present invention;

Fig. 3 is a structural schematic diagram of the connection between the magnetic whiteboard and the whiteboard support.

In the picture:

1-Universal wheel; 2-Base; 3-Vertical rod; 4-Fixed block; 5-Magnetic whiteboard; 6-Horizontal slot; 7-Disk; 11-horizontal rack; 12-locking screw; 13-module bar; 14-bump; 15-vertical chute; 16-locking nail; 17-notch; 18-locking screw A; 19-hand Wheel A; 20-rubber pad; 21-shaft; 22-lock screw B; 23-hand wheel B.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1-3, a teaching and demonstration device for depicting a sine curve includes a magnetic whiteboard. A horizontal through groove is placed horizontally in the middle of the magnetic whiteboard, and a rotating shaft perpendicular to the magnetic whiteboard is passed through the horizontal through groove. The groove moves horizontally and can rotate relative to the horizontal through groove with its axis as the rotation point. A disc is arranged at the front end of the rotating shaft, and a number of paintbrush jacks are arranged at intervals from inside to outside along the radial direction on the rotating shaft. There is a gear, and the rear side of the magnetic whiteboard is provided with a horizontal rack meshing with the gear above the gear. The horizontal rack is fixed on the lower end surface of the horizontal module bar, and the module bar is magnetically fixed to the rear side of the magnetic whiteboard.

In this embodiment, the distance between the gear and the disc is equal to the thickness of the magnetic whiteboard, the transverse rack and the module bar are locked by screws or the transverse rack and the module bar are integrated, and the transverse rack is parallel to the horizontal slot. The length of the module bar is not less than the length of the horizontal slot, and the distance between the horizontal rack and the horizontal slot is the radius of the gear.

In this embodiment, the diameter of the disc is not greater than 1/4 of the width of the magnetic whiteboard.

In this embodiment, the transmission of the transverse rack and the pinion may be a rolling pin transmission.

In this embodiment, two protrusions are symmetrically arranged on the left and right sides of the front side of the module bar, and two vertical slide grooves for accommodating the protrusions are symmetrically arranged on the rear side of the magnetic whiteboard, and locking screw holes are arranged on the protrusions. The locking screw hole runs through the protrusion, the module bar and is perpendicular to the magnetic whiteboard, and a locking screw is arranged in the locking screw hole, and the module bar is locked on the magnetic whiteboard through the locking screw.

In this embodiment, the module bar is made of strong magnetic material; or the contact surface between the module bar and the magnetic whiteboard is embedded with a magnet.

In this embodiment, a rolling bearing is arranged between the rotating shaft and the horizontal through groove, and the rolling bearing is installed on the rotating shaft.

In this embodiment, the disk and the gear are connected and locked with the rotating shaft through locking nails.

In this embodiment, there are multiple gears with different diameters, and only one gear is installed at the rear end of the rotating shaft in order to demonstrate waveforms of different frequencies.

In this embodiment, the magnetic whiteboard is installed on the whiteboard bracket, and the whiteboard bracket includes a base, vertical bars are arranged symmetrically on the left and right sides of the base, a fixed block is arranged on the inner side of the upper end of the vertical bar, and a shaft hole is placed horizontally on the upper end of the vertical bar. The middle part of the side is provided with a notch to accommodate the frame of the whiteboard, and the front and rear sides of the fixed block are provided with screw holes A, and a locking screw A is pierced in the screw hole A, the inner end of the locking screw A is against the whiteboard, and the outer end of the locking screw A is provided with Handwheel A, the shaft part is set in the middle of the outer surface of the fixed block, the shaft part is accommodated in the shaft hole and rotates with the shaft hole, the shaft part is provided with a screw hole B along the axial direction, and a locking screw B is arranged in the screw hole B, the lock The inner end of the tightening screw B is located in the screw hole B, and the outer end of the locking screw B is provided with a handwheel B.

In the present embodiment, the lower part of the base is provided with universal wheels with foot brakes.

In this embodiment, the inner end of the locking screw A is provided with a rubber pad.

A method for using a teaching demonstration device for depicting a sinusoidal curve, comprising the following steps:

(1) Move the rotating shaft to the left end of the horizontal chute;

(2) Insert the paintbrush into any paintbrush socket on the disc;

(3) Move the module bar up and down to make the horizontal rack mesh with the gear;

(4) The traction shaft moves horizontally or rotates the disc or gear in the horizontal through groove, and the horizontal rack and gear are meshed for transmission, so that the disc is driven to rotate through the shaft, and the trajectory of any particle in the circular motion can be intuitively used. On the disk, the sine wave curve is explained and drawn on the front side of the magnetic whiteboard through the paintbrush.

In this embodiment, the disk is transparent, which is convenient for students to understand the teaching principle in perspective; during the demonstration, coordinates and parameter descriptions can be marked on the front side of the magnetic whiteboard, and phases, symbols and diagrams can be marked on the disk; different The brush jack can draw curves with different amplitudes, and gears with different diameters can draw curves with different frequencies; the smaller the diameter of the gear, the greater the frequency of the curve drawn, and the farther the brush jack is from the center of the circle, the greater the amplitude of the curve drawn .

According to the physical meaning of the sine wave, when the disk plane rotates, the projection of any particle on the time axis is a sine wave. If the initial phase of the particle is Φ, the rotation frequency f, the amplitude A, the period T, and the circumference λ, then the rotational speed of the trajectory circle of the particle motion is 2πf, the circumference is 2πA, the diameter is 2A, and the initial phase is Φ, then there is Trigonometric formulas .

When teaching, the teacher displays and uses this demonstration device to perform demonstration experiments for students. Through actual observation and confirmation, students can obtain vivid and intuitive perceptual knowledge and form correct and profound theoretical concepts.

This demonstration device not only provides visual perceptual materials, arouses interest in learning, concentrates students' attention, and helps to understand, memorize and consolidate the knowledge they have learned; it also enables students to carry out thinking activities through observation and thinking, Develop observation, imagination and thinking skills.

The above preferred embodiments have further described the purpose, technical solutions and advantages of the present invention in detail. It should be understood that the above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Within the spirit and principles of the present invention, any modifications, equivalent replacements, improvements, etc., shall be included within the protection scope of the present invention.

Claims (9)

1. a kind of describe sinusoidal teaching demonstration device, it is characterised in that：It is horizontal in the middle part of magnetic white board including magnetic white board Have horizontal through slot, be installed in horizontal through slot one perpendicular to magnetic white board shaft, shaft can laterally move in horizontal through slot, Shaft front end is provided with disk, if the radially dry brush jack of interval setting from the inside to the outside, the setting of shaft rear end are with teeth on disk Wheel, magnetic white board rear side are provided with meshed horizontal tooth bar above gear, and horizontal tooth bar is fixed on horizontal module Lower end surface, module strip are fixed with magnetic white board trailing flank magnetic；

Magnetic white board is mounted on whiteboard bracket, and whiteboard bracket includes pedestal, is symmetrically arranged with vertical bar, vertical bar at left and right sides of pedestal Fixed block is provided on the inside of upper end, vertical bar upper end is horizontal axis hole, and setting accommodates blank frame portion in the middle part of fixed block medial surface Screw hole A is arranged in notch, fixed block front and back sides, tie down screw A is equipped in screw hole A, the inner end tie down screw A is against blank, lock The tight outer end screw rod A is provided with handwheel A, and axle portion is arranged in the middle part of fixed block lateral surface, and axle portion is accommodated in axis hole and matches with axis hole rotation It closes, it is axially disposed in axle portion to have screw hole B, tie down screw B is provided in screw hole B, the inner end tie down screw B is located in screw hole B, lock The tight outer end screw rod B is provided with handwheel B.

2. according to claim 1 describe sinusoidal teaching demonstration device, it is characterised in that：Module strip leading flank is left Right two sides are symmetrical arranged there are two convex block, and magnetic white board trailing flank is symmetrically set with the vertical chute of two receiving convex blocks, It is provided with locking screw holes on convex block, locking screw holes are provided in locking screw holes through convex block, module strip and vertical with magnetic white board Lock-screw, module strip are locked on magnetic white board through lock-screw.

3. according to claim 1 or 2 describe sinusoidal teaching demonstration device, it is characterised in that：Module strip is strong Magnetic force material is made；Or the contact surface of module strip and magnetic white board is embedded with magnet.

4. according to claim 1 describe sinusoidal teaching demonstration device, it is characterised in that：Shaft and horizontal through slot Between be provided with rolling bearing, rolling bearing is mounted in shaft.

5. according to claim 1 describe sinusoidal teaching demonstration device, it is characterised in that：Disk, gear are through locking It marks closely and connect locking with shaft.

6. according to claim 1 or 2 describe sinusoidal teaching demonstration device, it is characterised in that：Gear setting is more A, each gear diameter is different, and a gear is only installed in shaft rear end.

7. according to claim 1 describe sinusoidal teaching demonstration device, it is characterised in that：Pedestal lower part is provided with Universal wheel with service brake.

8. according to claim 1 describe sinusoidal teaching demonstration device, it is characterised in that：The inner end tie down screw A It is provided with rubber pad.

9. a kind of application method for describing sinusoidal teaching demonstration device describes sine using as claimed in claim 6 The teaching demonstration device of curve, which is characterized in that include the following steps：

（1）Shaft is moved to horizontal concrete chute left part；

（2）Paintbrush is inserted into any paintbrush jack on disk；

（3）Moving up and down module strip engages horizontal tooth bar with gear；

（4）Traction shaft laterally moves in horizontal through slot or rotating circular disc or gear, horizontal tooth bar and gear engaged transmission, To disc-rotated by shaft, the paintbrush on disk draws sine wave curve in magnetic white board leading flank.