Machine element
Machine elements, components which are included in the same or similar form at least in industrial structures. The name derives from the machines. But machine elements occur also in plants, apparatus, appliances and modern buildings. Their properties are well researched and therefore they offer reliable solutions for recurring individual tasks in designing and building technical structure.
The term subelement often refers to the smallest possible part. That is, in this context different. This refers to the smallest sensible organizational unit that is promising for the function and construction of engineering structures. Thus, a bicycle chain which is composed of the parts pin, sleeves, and plates, treated as a whole, as a machine part of a bicycle.
The most common machine elements are used to connect the main parts of a technical fabric, which may be even more complex machine elements used. A typical connector is the bolt ( with nut).
Standard machine elements such as fasteners and gaskets are standardized in almost all properties can be thus to the creation of favorable economic principle interchangeability finished separately and keep them available.
More complex machine elements are, for example, waves, wheels, bearings, couplings and gears. The standardization is limited with them mostly on shape and size of the lands to other parts. The division of labor principle interchangeability is nevertheless applicable, such as in the roller bearings in some cases.
The machine elements to be usually designed individually for the technical structure in which it is used. This is only possible through good knowledge of their tax bases. These skills and knowledge are machine elements in the subject - one of the key foundation subjects in the study of mechanical engineering - mediated.
Structure
The classification of machine elements in manuals, tables or textbooks usually begins with the connecting elements. Due to the variety of machine elements beyond but so far no uniform structure is formed. They are often treated without recognizable systematization criterion in any order. Textbooks will occasionally make the work focus of their authors recognize because some machine elements are only briefly or not treated.
A proposal for a basic systematization Karl Kutzbach made in 1927. It is based on the definition that a machine is the use of all means for the controlled mastery of spatial and shape change of substance or energy (or information ). Siegfried Hildebrand him in 1968 at the breakdown of precision mechanical components, which is in principle valid for all machine elements, taken up.
It is different working elements of matching elements. The work items are divided into memory, cables and converters, as each function value is stored, must be propagated and transformed. The ... matching elements serve to influence the work items or to control and regulate. You ... are therefore divided into rest elements (resistors ) in the switching elements and control and regulating elements. Peace elements have the task of generating an idle state or to receive. They are related to the guide elements, but have ruled out only individual degrees of freedom. Rest elements in the strict sense are locking and attacks. Special rest elements are couplings ( locking between two waves), brakes (variable resistor ) and switch (Received and achieving preferred positions ).
The following list contains fasteners and other selected machine elements, the latter according to the proposal of Kutzbach / Hildebrand:
- Fasteners screw connections
- Riveted joints
- Welded joints
- Solder joints
- Adhesive joints
- Spring
- Flywheels
- Plain bearings and roller bearings
- Axles and shafts
- Gears and gear drives
- Friction gear
- Traction drives
- Helical gear
- Linkage
- Cam gear
- Locking
- Attacks
- Couplings and Clutches
- Brakes
- Switch
- Derailleur (eg Geneva drives )
- Brake controller ( for example, governor )
- Hemmregler (for example, clocks inhibition)
- Other elements seals
- Pipes, tanks and valves