Understanding Machines: Types, Mechanisms, and Principles

A machine is a set of parts or assemblies, each capable of using, transforming, managing, or regulating the action of a force, muscle, or other source, to assist people in their daily work. Any machine is formed by a series of mechanisms composed of fitted parts, allowing energy to be converted into another form of energy. Tools are hand implements used for working materials. When these tools are mounted on machines that replace human action with a series of mechanical movements, it becomes a machine tool. A machine is primarily constituted by the structure: the machine will comprise a series of elements joined together to support the mechanisms of the machine. Mechanisms: These are formed by a set of pieces coupled together to transmit, modify, and regulate energy and forces acting on a machine. The types of movements that a machine can generally perform are basically: Linear motion: This is when an object moves by applying a force that compels it to displace along a straight line. Curvilinear motion: This is when an object moves by applying a force that makes it scroll along a curved trajectory. Alternate Movement: This is movement in different directions in an alternating way, i.e., a trajectory that has a back and forth motion. Forces: Force (F) is anything capable of changing the state of rest or motion of a body. It is expressed in Newtons (N). Work: Work (W) is the result obtained by applying a force on a body and moving it a certain distance (Δx). It is expressed in joules (J). Power: The power (P) of a machine indicates the amount of work it can perform in a given time (t). It is expressed in watts (W). Performance: In any machine, the work or labor supplied by the motor (Wm), and the actual work the machine performs, or useful work (Wu), are not equal because some engine work is transformed into heat, usually within the machine itself. Thus, the mechanical performance (η) is the ratio between the useful work obtained by the machine and the engine work applied for this work.

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Machines can be simple: These use and basically transform muscle power and are the basis for the design and construction of machines, or complex machines: These are based on simple machines. They are formed by mechanisms that transform movement from one element to other components that perform the work for which the machine is designed. There are three types of complex machines: Motor machines: These turn mechanical energy into other forms of energy, such as hydropower or electricity. Generating machines: These receive hydropower, wind, fossil fuels, etc., and transform it into electricity, as in the case of generators and dynamos. Operational machines: These are machines that convert one type of energy into useful work. A lever is a rigid bar that relies on a support called a fulcrum, around which it rotates. By applying a relatively small force at one point on the bar, called power, this force can overcome a larger force called resistance, located at another part of the bar. The closer the resistance is to the fulcrum, the less force is required. Types of levers: First class: These have the fulcrum located between the power and the resistance. Second class: These have the resistance located between the power and the fulcrum. Third class: These have the power located between the fulcrum and the resistance, such as tweezers. The Inclined Plane: This is a plane that has a certain inclination on the horizontal plane and serves to move an object from one level to a higher one with less effort than if the same object were lifted vertically without any mechanism. On a length (L), the force (F) necessary to move a weight (W) from position A to another B at a height (h), without considering friction, is determined by this expression: