Device for connecting two rails on an optical laws experiment bench allowing precise alignment and rotational movement between these two benches.

Abstract

Device for connecting two rails on an optical laws experiment bench allowing precise and rigid abutment of the two benches, as well as a possibility of rotation from -90° to +90° between these two benches, characterized by: a goniometric mechanism (a), a graduated angular indicator disc (b) both located under the rails, dovetails (c) acting both as a fixing and sliding connection with the rails, connecting pieces between the rails and the goniometric mechanism (d), a retractable column (e), clamping screws (f), support feet (g). . Figure for the abstract: [Fig 1]

Description

Title of the invention: Device for connecting two rails on an optical laws experiment bench allowing precise alignment and rotational movement between these two benches.

[0001] The present invention relates to a device for connecting two rails on an optical laws experiment bench allowing precise alignment and rotational movement between these two benches.

[0002] The main purpose of teaching tools is to be used in schools for the training of high school students, technicians and engineers. They are mostly tools for experimenting with physical subjects which are used during lessons. On these benches, components are installed (light source, diffraction elements, measuring tools, etc.) which are placed on intermediate fixing elements called riders, and which slide and lock in position on the bench (also called rail). For the experiments to be carried out in good observation conditions, it is necessary that the rail provides guidance for the elements with the least possible play, and that the rail / rider pair has a locking system allowing the expected functional precision to be offered (precision relative to the optical axis: absence of torsion and lateral, longitudinal or vertical deviation).

[0003] In the case of the present patent application, four additional functions are sought to vary the experiments. In this context, the device must be able to study the laws of optics such as focometry and the deflection of light through a prism. To do this, it is necessary that the device allows: - a rotation from -90° to +90°, - an abutment of the two profiles in line, - a rigidity of the assembly in the abutted position, - and all while ensuring precision (as we have seen, mainly linked to the rigidity of the bench) in any position.

[0004] State of knowledge: The state of knowledge can be established from two angles:

[0005] - the first concerns the state of known device technology of experimentation of the laws of optics,

[0006] - the second concerns other known devices, which allow rigid abutment, the straightness and rotation of two separate mechanical elements.

[0007] Regarding the didactic apparatus for experimenting with the laws of optics: Let us recall that the study of optics began in Antiquity. If the laws of reflection were known to Euclid (-330 BC) and the laws of refraction were Published around the year 1000, the first optical instruments appeared in the 17th century. They were mainly used for the study of astronomy.

[0008] It was from 1850 that devices and accessories were developed intended to produce experiments on optical phenomena in front of a large audience. In particular, optical benches, which are devices used in education to teach the fundamental principles of optics, such as reflection, refraction, diffraction, interference, etc. Note the "Duboscq" optical elements, or the first optical benches built in the 1930s where we notice for the first time the presence of a "U" shaped metal rail with a length of approximately 1.5m (which will become a size standard).

[0009] Modern optical benches are designed to be easy to use and provide high accuracy in the measurements made. They are equipped with many accessories such as prisms, lenses, mirrors, filters and diaphragms that allow a wide variety of experiments to be carried out. Some benches are also equipped with measuring devices such as graduated scales, micrometers and interferometers that allow angles, distances and wavelengths to be measured accurately.

[0010] The main systems available on the market include a single-piece rail (also called a bench) of more than 1.5m, which makes them bulky. They are more or less rigid depending on the shape used. The shape of the profile is therefore essential, both in its design and its manufacture, to guarantee rigidity capable of providing precise experiments.

[0011] The present applicant had also filed a patent No. FR299805 to guarantee this necessity. In this patent, the shape of the profile determines the rigidity of the bench and the positioning of the rider (supporting the optical tool placed on the bench) on it.

[0012] A manufacturer of equipment for panoramic photography offers another telescopic optical bench system with several rails and coupling pieces between the rails ("NODAL Ninja"®). But these systems do not allow rotation between the two pieces of rails, which is necessary for studying the deflection of light.

[0013] The main manufacturers offer a goniometric coupling system (for example, the company "TWINSE") which allows two benches to be connected together, to give them a precise angle in order to measure, for example, the deviation of a light beam which has passed through a prism. But these systems are not an integral part of the benches. They are accessories used only for angular deviation. So much so that as far as optical benches are concerned, no solution satisfies the triple objective: to ensure an angular connection of two rails while guaranteeing the rigidity and precision of the entire system in linear position butted

[0014] Relating to mechanical devices which allow the rigid joining, straightness and rotation in both directions of two separate mechanical elements without play: Many systems have been developed allowing both the rotation of two profiles between them and their locking in a chosen position.

[0015] For example, the draftsman's compass, the system for "breaking" the hunting rifle, the articulated arms used for construction machinery, etc. The most characteristic of this equipment and the closest to our need is the system used for multi-function ladders.

[0016] This is indeed a mechanism connecting two initially distinct profiles and which makes it possible to obtain both the linear and rigid abutment of the profiles (case of the straight ladder) as well as their assembly according to a chosen angle (case of the scaffolding). But if this system is sufficiently rigid to support the weight of a human being, it does not provide the precision required for the study of the laws of optics. In addition, the rotation permitted by this mechanical system is only 180° in the clockwise or counterclockwise direction but not both at the same time.

[0017] Thus, whether in the field of optics, or in another field of activity, there is no identifiable system that can meet the requirements of: rotation from -90° to +90°, possibility of joining the two profiles in line, rigidity of the assembly in the joined position, and precision of the system in any position.

[0018] Presentation of the invention: the invention relates to a device for connecting two rails for experimenting with the laws of optics, allowing precise and rigid joining of the two rails, as well as a possibility of rotation from -90° to +90° between these two rails.

[0019] This device is equipped with: a goniometric mechanism (a), a graduated angular indicator disc (b) both located under the rails, dovetails (c) acting both as a fixing and as a sliding connection with the rails, connecting pieces between the rails and the goniometric mechanism (d), a retractable column (e), clamping screws (f), support feet (g).

[0020] This device uses a method characterized in that the dovetails (c) act as a sliding connection, according to a first abutting position of the rails, these connections reinforce the three-dimensional rigidity of the bench; while in a position distant from the rails, the connecting pieces (d) maintain the latter in a distant position allowing a possibility of rotation of -90° to +90° between these two rails.

[0021] This device also differs from conventional devices by the absence of system parts in the contact zone between the two rails (see [Fig.l]), the goniometric mechanism (a) and the graduated angular indicator disc (b) being located under the rails, and the column (e) being retractable.

[0022] This configuration, connecting pieces (d) plus dovetails (c) and the possibility of moving the entire system along the rails (see [Fig.2]), makes it possible to guarantee absolute three-dimensional rigidity (in torsion, longitudinally and laterally) of the assembled bench made up of the two butted rails.

[0023] In fact, the rigidity is obtained by one of the two sets of connecting pieces and dovetails (c) which are positioned in the two rails at the same time.

[0024] If conventional devices effectively allow rotation and the precision of the orientation of the system to be ensured in an angular study interval of -90° to +90°, the system designed also allows the two rails to be joined in line while guaranteeing the rigidity necessary for the study of the laws of optics.

[0025] [Fig. 1] General view of the device in a position suitable for ensuring an angle of rotation of the two rails.

[0026] [Fig.2] General view of the device with the two rails butted together to form a straight line. Note that a dovetail is positioned in both rails at once and that the clamping screws (f) fix the butted rails, all ensuring perfect rigidity of the bench.

[0027] Glossary: (a) of a goniometric mechanism, (b) a graduated angular indicator disc, (c) dovetails, (d) connecting parts with the rails, (e) a retractable column, (f) clamping screw, (g) supporting feet.

Claims

Claims

1. Device for connecting two rails on a bench for experimenting with the laws of optics, allowing precise and rigid joining of the two benches, as well as a possibility of rotation from -90° to +90° between these two rails, characterized by: a goniometric mechanism (a), a graduated angular indicator disc (b) both located under the rails, dovetails (c) acting both as a fixing and as a sliding connection with the rails, connecting pieces between the rails and the goniometric mechanism (d), a retractable column (e), clamping screws (f), support feet (g).

2. Method according to claim 1, characterized in that the dovetails (c) act as a sliding connection, in a first abutting position of the rails, these connections reinforce the three-dimensional rigidity of the bench; while in a position distant from the rails, the sliding connections maintain the latter in a distant position allowing a possibility of rotation of -90° to +90° between these two rails.

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