Exact Slider Crank Ellipse and Straight-line Linkage
- Title:
- Exact Slider Crank Ellipse and Straight-line Linkage
- Title (German):
- Genauer Ellipsenlenker
- Collection:
- Reuleaux Kinematic Mechanisms Collection
- Set:
- S. Straight-line Mechanisms
- Designer:
- Reuleaux, F. (Franz), 1829-1905
- Manufacturer:
- Gustav Voigt Werkstatt
- Date:
- 1882
- Country:
- Germany
- Voigt Catalog Model:
- S1
- File Name:
- S01.jpg
- Work Type:
- Mechanical model
- Materials/Techniques:
- cast iron and brass on wood pedestal
- Subject:
- Kinematics of Machinery
- Measurement:
- 201 x 90 (millimeters, width x depth)
201 x 119 x 303 (millimeters, width x depth x height) - Description:
- The use of linkages to draw mathematical curves has a long history. The double slider crank or 'Trammel' mechanism for example (Model S-2), has long been used to draw exact ellipses. What is not well known is that a special form of the slider crank mechanism (Model C-2) will also draw an ellipse as well as an exact straight-line when the connecting link between the crank and the slider have equal lengths. The straight line is then generated by an extension of the connecting link by the length of the crank as shown in the model S-1. A working model of this mechanism may also found in the Deutsches Museum in Munich in the Mathematics section. The description attributes the invention to Benjamin Bramer (1588-1652) c. 1600. However there is also credit for an ellipse drawing mechanism given to Leonardo da Vinci by Reuleaux (See Models D-10, D-12) as well as to a Dutchman von Schooten around the same period. This suggests that the idea of an ellipse drawing device may have been common knowledge among artists and mathematics in the Renaissance. There was great interest among artists in the use of geometry (e.g. perspective) in representing exactly real world objects. [See also tutorial on "How to Draw an Ellipse'] The use of straight-line mechanisms found application to power machines in the Watt-Boulton steam engines of the late 18th century. Their function was to translate the linear motion of the oscillating piston into the rocking motion of the balance arm. However Machine Age applications of straight-line mechanisms relied on linkages with cylindrical joints and not slider-crank mechanisms. Some of these pure linkage straight-line mechanisms are described in models S-14, S-24, S-31 and S-35. [Francis Moon 2003-07-01]
The 220 models in Cornell University’s Reuleaux Collection were built in the late 19th century to demonstrate the elements of machine motion, as theorized by the German engineer Franz Reuleaux. The University acquired the models in 1882 for use in teaching and research. The Reuleaux models are classified according to the alphanumeric schema employed in the catalog of the manufacturer, Gustav Voigt. The letter in a model's ID (e.g., B14 or S35) refers to a class of mechanism; the number is a specific instance of the class. This classification scheme is a simplified version of the taxonomy of machine elements elaborated in Reuleaux's work. - Repository:
- Sibley School of Mechanical and Aerospace Engineering, Cornell University
- Format:
- Image
- Rights:
- Photography credit: Jon Reis (www.jonreis.com). Jon Reis Photography grants Cornell University Libraries and the Cornell College of Engineering the rights to display copyrighted images of the Reuleux collection of kinetic machines on the Cornell University and National Science Digital Library web sites and for unlimited use in Cornell University Library publications for education purposes only. Rights for all other uses, including but not limited to, editorial, commercial, advertising, web use and display by third parties not affiliated with Cornell University are reserved by the photographer. The written permission of any copyright and other rights holders is required for distribution, reproduction, or other use that extends beyond what is authorized by fair use and other statutory exemptions. Responsibility for making an independent legal assessment of an item and securing any necessary permissions ultimately rests with persons desiring to use the item. For questions about this item or other items please contact the Physical Sciences Librarians at pslref@cornell.edu.