FR2650687A1 - Demonstration, manipulation and educative device for studies in optics of colours and of stroboscopy - Google Patents

Abstract

The invention relates to a demonstration device for teachers making it possible to study the mixing, addition, subtraction of colours and stroboscopy. The device consists of a disc 1 including an aperture 2 making it possible to house a maximum of 6 portions made of coloured cardboard or bearing markings. These portions will be held during rotation by elastic 10 between the disc 1, the crowns 1' and 1''. The assembly will be mounted on the horizontal shaft of a motor 8 the speed of which can be fixed or variable. One variant of this device will be used for operation by the pupils or as an educational toy. In this case, the device is formed of a compact transparent box with a horizontal position of the disc or plate. The device according to the invention is intended for educational establishments and for children.

Description

DESCRIPTION
The present invention relates to a demonstration device for studying the mixing, addition and subtraction of colors in optics. The device also allows studies in stroboscopy in accordance with the curricula of colleges and high schools.

The concept of color, a fortiori their mixing, is poorly understood by the students. Until now, the disc of
Newton classic present in educational establishments contains a certain number of colors whose mixture by rotation gives the impression of the shade "white". The device according to the invention can go further since, in addition to the possibility of reconstituting the "white" shade, it makes it possible to play at the same time on the number, the nature as well as on the relative proportion of the colors.

 In stroboscopy, the device allows you to play on the number of marks and, depending on the equipment, the determination of the speed of rotation of a disc.

 According to a first characteristic, the device can house portions of strong cardboard each carrying one or more colors for the study of colors or white markers on a black background for stroboscopic studies.

 Figure 1 shows in section the device according to the invention.

 FIG. 2 represents a front view of the device.

 Figure 3 represents a portion of strong cardboard.

 Figures 4 and 5 represent a variant of this device.

 With reference to these drawings, the device represented by FIGS. 1 and 2 consists of a disc (1) which can accommodate in (6) strong cardboard portions - at most 6- colored or bearing white marks on a black background that the user introduced through the opening (2). The whole will be mounted on the horizontal axis of a motor (8) and fixed by the screw (4) to the part (7) secured to the motor by means of the screw (9). The motor can be at fixed speed -3500 or 4000 rpm or variable speed ranging from O to 6000 rpm. In the latter case, the motor will be controlled by a control box not illustrated comprising a speed variator, a push button, a switch, a battery compartment and a transformer for possible connection to the mains.

 FIG. 3 represents a portion of strong cardboard comprising truncations (14) and (16) at the location of the partitions (3) and (5). These truncations would be useless if thin partitions -0.5 mm are provided as an example.

 These portions will be held in place by a circular elastic band (10) whose stiffness can counteract the centrifugal force due to the rotation of the disc. This elastic is housed between the disc (1) and the crown (1 ') integral with the partitions (3). This elastic can be replaced by screws (13) which are housed in the hole (18) that each portion can have for this purpose in order to block it.

 The lower part (12) of each portion is plasticized to prevent any early wear due to the introduction thereof.

This part will be held in place by the crown (1 ") secured to the disc.

 The upper part (17) is painted black to avoid any dirt. The coloring and markings are done at the level of the part (5).

The cardboard portions are 78 distributed as follows:
- for the study of colors: 6 portions of each of the following colors: purple; indigo; blue; green; yellow; orange; red; cyan; magenta; "white" (blank).

 -to obtain the "white" shade: 6 portions each carrying the 7 colors of the rainbow suitably dosed.

 -in strobe: 6 portions with 1 mark and 6 portions with 2 marks.

 This number can be extended to other so-called purple colors for example.

Here are some non-limiting examples of using the device:
COLOR STUDY:
-to have the "white" shade: the demonstrator uses the 6 portions each containing the colors of the rainbow.

 -to have a mixture of 2 colors, the demonstrator uses 3 portions of each of these 2 colors which he alternates.

 -to have a mixture of 3 colors, the demonstrator uses 2 portions of each of these 3 colors which it has alternately.

 -to have any mixture of colors in well defined proportions, the demonstrator uses the portions corresponding to these colors by playing on their number, their proportion and their nature.

 -to have the black-white mixture in a given proportion, the demonstrator uses white portions; the support disc (1) being in black plastic will play the role of "black tint".

STROBOSCOPY:
-the user can obtain 1, 2, 3, 6 or 12 marks as needed.

-the user can also play on the speed of rotation by making a less precise adjustment using the potentiometer in the case of using the control box and by proposing to determine this speed in a more precise by stroboscopy. This could be the object of a manipulation whose aim is to show the students the interest of stroboscopy in everyday life and in industry such as in automobile mechanics or the adjustment of the speed of rotation of the plate of a turntable - discs for example
A VARIANT OF THE DEVICE:
It consists of the use of a similar device (Figures 4 and 5) as an educational game or manipulation device for the students.

The principle remains the same with the following modifications compared to the device described above:
- horizontal position of the device with 3 rubber feet (29).

 -compact transparent compact (28) comprising a plate (19) fixed to the motor (32) by means of the part (22). A washer (24) ensures the stability of the plate. The motor is maintained by 6 bars (31) -3 at the top and 3 at the bottom- integral with the shoemaker and controlled by the push button (33).

the introduction of a cardboard portion (20) is done as follows:
unscrewing the wheel (21);
introduction of the upper part of the portion under the corners (25);
folding down the portion;
screwing the knob (21).

 -a battery compartment (30) which is accessed from the bottom.

 -access to the case is made if necessary from above by unscrewing the screws (26) fixed on the support (27).

 -children or pupils can cut out cardboard portions themselves, which they freely color in order to obtain original color mixtures. These blank portions can be supplied in addition to a batch similar to that which accompanies the demonstration device, except for the portions bearing markers, the stroboscopic part being excluded.

 By way of nonlimiting example, the demonstration device will have a diameter of 25.4 cm and will be made of black acrylonitrile butadiene-styrene (ABS) by injection molding. The handling and educational device will have a diameter of 16.6 cm and will be made of transparent plastic, such as polymethylmethacrylate (Plexiglas or PMM) by the same molding operation. The different elements will be 0.2 cm thick.

 The device according to the invention is intended for schools and children.

Claims (3)

 1) Device for studying the mixture, the addition, the subtraction of colors as well as the characteristic stroboscopy in that it comprises a disc (1) integral with a crown (1 ') itself integral with the partitions (3 ). The space between the disc and the crown forms an opening (2) allowing the introduction of colored cardboard portions or those bearing markers (Figure 3).  2) Device according to claim 1 characterized in that the vertical disc (1) is replaced by the horizontal plate (19) attaching to a transparent compact housing (28) and constituting the support of the colored or blank cardboard portions whose attachment is provided by the corners (25) and the wheel (21).  3) Device according to claim 1 characterized in that the cardboard portions are held by a circular elastic (10) whose stiffness can counteract the centrifugal force due to the rotation of the disc. This elastic fits between the disc (1) and the crown (1 ').