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Machine Tools
A machine tool is a machine for handling or machining metal or other rigid materials, usually by cutting, boring, grinding, shearing, or other forms of deformations. Machine tools employ some sort of tool that does the cutting or shaping. All machine tools have some means of constraining the workpiece and provide a guided movement of the parts of the machine. Thus, the relative movement between the workpiece and the cutting tool (which is called the toolpath) is controlled or constrained by the machine to at least some extent, rather than being entirely "offhand" or " freehand". It is a power-driven metal cutting machine which assists in managing the needed relative motion between cutting tool and the job that changes the size and shape of the job material. The precise definition of the term ''machine tool'' varies among users. While all machine tools are "machines that help people to make things", not all factory machines are machine tools. Today machine tools are typically ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tool Ways
A way (sometimes known as a slideway, guideway, or bedway) is a type of linear bearing, specifically a linear plain bearing, in a machine tool. It facilitates precise linear motion along a given axis. A way is ground, scraped, or (less often) molded to be very flat, and ways often come in pairs to ensure a flat plane for the carriage or sliding element (slide) to move along smoothly. Ways are usually lubricated with way oil (a kind of machine oil specially made to adhere to the ways while vertical). Ways have been used since the 19th century and are a critical part of manufacturing processes, especially those requiring low tolerances such as machining. They have been made of various materials over the years, ranging from wood to cast iron, and nowadays including plastic alloys and special polymer materials. They are crafted with painstaking precision, usually being scraped into near total flatness with hand tools. This flatness is required to both provide good results in the man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accuracy And Precision
Accuracy and precision are two measures of ''observational error''. ''Accuracy'' is how close a given set of measurements (observations or readings) are to their ''true value''. ''Precision'' is how close the measurements are to each other. The International Organization for Standardization (ISO) defines a related measure: ''trueness'', "the closeness of agreement between the arithmetic mean of a large number of test results and the true or accepted reference value." While ''precision'' is a description of ''random errors'' (a measure of statistical variability), ''accuracy'' has two different definitions: # More commonly, a description of ''systematic errors'' (a measure of statistical bias of a given measure of central tendency, such as the mean). In this definition of "accuracy", the concept is independent of "precision", so a particular set of data can be said to be accurate, precise, both, or neither. This concept corresponds to ISO's ''trueness''. # A combination of both ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Numerical Control
Computer numerical control (CNC) or CNC machining is the automated control of machine tools by a computer. It is an evolution of numerical control (NC), where machine tools are directly managed by data storage media such as punched cards or punched tape. Because CNC allows for easier programming, modification, and real-time adjustments, it has gradually replaced NC as computing costs declined. A CNC machine is a motorized maneuverable tool and often a motorized maneuverable platform, which are both controlled by a computer, according to specific input instructions. Instructions are delivered to a CNC machine in the form of a sequential program of machine control instructions such as G-code and M-code, and then executed. The program can be written by a person or, far more often, generated by graphical computer-aided design (CAD) or computer-aided manufacturing (CAM) software. In the case of 3D printers, the part to be printed is "sliced" before the instructions (or the prog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer
A computer is a machine that can be Computer programming, programmed to automatically Execution (computing), carry out sequences of arithmetic or logical operations (''computation''). Modern digital electronic computers can perform generic sets of operations known as Computer program, ''programs'', which enable computers to perform a wide range of tasks. The term computer system may refer to a nominally complete computer that includes the Computer hardware, hardware, operating system, software, and peripheral equipment needed and used for full operation; or to a group of computers that are linked and function together, such as a computer network or computer cluster. A broad range of Programmable logic controller, industrial and Consumer electronics, consumer products use computers as control systems, including simple special-purpose devices like microwave ovens and remote controls, and factory devices like industrial robots. Computers are at the core of general-purpose devices ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Servomechanism
In mechanical and control engineering, a servomechanism (also called servo system, or simply servo) is a control system for the position and its time derivatives, such as velocity, of a mechanical system. It often includes a servomotor, and uses closed-loop control to reduce steady-state error and improve dynamic response. In closed-loop control, error-sensing negative feedback is used to correct the action of the mechanism. In displacement-controlled applications, it usually includes a built-in encoder or other position feedback mechanism to ensure the output is achieving the desired effect. Following a specified motion trajectory is called servoing, where "servo" is used as a verb. The ''servo'' prefix originates from the Latin word ''servus'' meaning slave. The term correctly applies only to systems where the feedback or error-correction signals help control mechanical position, speed, attitude or any other measurable variables. For example, an automotive power win ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technological Convergence
Technological convergence is the tendency for technologies that were originally unrelated to become more closely integrated and even unified as they develop and advance. For example, watches, telephones, television, computers, and social media platforms began as separate and mostly unrelated technologies, but have converged in many ways into an interrelated telecommunication, media, and technology industry. Definitions "Convergence is a deep integration of knowledge, tools, and all relevant activities of human activity for a common goal, to allow society to answer new questions to change the respective physical or social ecosystem. Such changes in the respective ecosystem open new trends, pathways, and opportunities in the following divergent phase of the process". Siddhartha Menon defines convergence as integration and digitalization. Integration, here, is defined as "a process of transformation measure by the degree to which diverse media such as phone, data broadcast and inf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jacquard Loom
The Jacquard machine () is a device fitted to a loom that simplifies the process of manufacturing textiles with such complex patterns as brocade, damask and matelassé. The resulting ensemble of the loom and Jacquard machine is then called a Jacquard loom. The machine was patented by Joseph Marie Jacquard in 1804, based on earlier inventions by the Frenchmen Basile Bouchon (1725), Jean Baptiste Falcon (1728), and Jacques Vaucanson (1740). The machine was controlled by a "chain of cards"; a number of punched cards laced together into a continuous sequence. Multiple rows of holes were punched on each card, with one complete card corresponding to one row of the design. Both the Jacquard process and the necessary loom attachment are named after their inventor. This mechanism is probably one of the most important weaving innovations, as Jacquard shed (weaving), shedding made possible the automatic production of unlimited varieties of complex pattern weaving. The term "Jacquard" is no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Musical Box
A music box (American English) or musical box (British English) is an automatic musical instrument in a box that produces Musical note, musical notes by using a set of pins placed on a revolving cylinder (geometry), cylinder or disc to pluck the tuned teeth (or lamellophone, ''lamellae'') of a steel comb#Making music, comb. The popular device best known today as a "music box" developed from musical decorative boxes#Snuff box, snuff boxes of the 18th century and were originally called (French for "chimes of music"). Some of the more complex boxes also contain a tiny drum and/or bells in addition to the metal comb. History The Symphonium company started business in 1885 as the first manufacturers of disc-playing music boxes. Two of the founders of the company, Gustave Brachhausen and Paul Riessner, left to set up a new firm, Polyphon, in direct competition with their original business and their third partner, Oscar Paul Lochmann. Following the establishment of the Original Mus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Van Der Waals Force
In molecular physics and chemistry, the van der Waals force (sometimes van der Waals' force) is a distance-dependent interaction between atoms or molecules. Unlike ionic or covalent bonds, these attractions do not result from a chemical electronic bond; they are comparatively weak and therefore more susceptible to disturbance. The van der Waals force quickly vanishes at longer distances between interacting molecules. Named after Dutch physicist Johannes Diderik van der Waals, the van der Waals force plays a fundamental role in fields as diverse as supramolecular chemistry, structural biology, polymer science, nanotechnology, surface science, and condensed matter physics. It also underlies many properties of organic compounds and molecular solids, including their solubility in polar and non-polar media. If no other force is present, the distance between atoms at which the force becomes repulsive rather than attractive as the atoms approach one another is called the van der ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euclidean Vector
In mathematics, physics, and engineering, a Euclidean vector or simply a vector (sometimes called a geometric vector or spatial vector) is a geometric object that has magnitude (or length) and direction. Euclidean vectors can be added and scaled to form a vector space. A '' vector quantity'' is a vector-valued physical quantity, including units of measurement and possibly a support, formulated as a '' directed line segment''. A vector is frequently depicted graphically as an arrow connecting an ''initial point'' ''A'' with a ''terminal point'' ''B'', and denoted by \stackrel \longrightarrow. A vector is what is needed to "carry" the point ''A'' to the point ''B''; the Latin word means 'carrier'. It was first used by 18th century astronomers investigating planetary revolution around the Sun. The magnitude of the vector is the distance between the two points, and the direction refers to the direction of displacement from ''A'' to ''B''. Many algebraic operations on real numbe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cam (mechanism)
A cam is a rotating or sliding piece in a linkage (mechanical), mechanical linkage used especially in transforming rotary motion into linear motion. It is often a part of a rotating wheel (e.g. an eccentric wheel) or shaft (e.g. a cylinder with an irregular shape) that strikes a lever at one or more points on its circular path. The cam can be a simple tooth, as is used to deliver pulses of power to a steam hammer, for example, or an Eccentric (mechanism), eccentric disc or other shape that produces a smooth reciprocating (back and forth) motion in the ''Cam follower, follower'', which is a lever making contact with the cam. A cam timer is similar, and these were widely used for electric machine control (an electromechanical timer in a washing machine being a common example) before the advent of inexpensive electronics, microcontrollers, integrated circuits, programmable logic controllers and digital control. Camshaft The cam can be seen as a device that converts rotational mot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
