Compensator

compensator [′käm·pən‚sād·ər]

(control systems)

A device introduced into a feedback control system to improve performance and achieve stability. Also known as filter.

(electronics)

A component that offsets an error or other undesired effect.

(optics)

A device, usually consisting of two quartz wedges, for determining the phase difference between the two components of elliptically polarized light.

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compensator

In fire sprinkler systems, a device intended to minimize false alarms caused by small increases in service pressure of the water supply.

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Compensator 

in technology:

(1) A device or filler for compensating or balancing the effect of various factors—such as temperature, pressure, and position—on the condition and operation of structures, systems, machines, and instruments. It ensures that they are in working order by eliminating the effect of the factors listed above; it is also used to measure or adjust physical quantities (for example, an optical compensator). The design of compensators that are used in the assembly and maintenance of machines is determined by the limiting values and the necessary compensation accuracy.

A distinction is made between fixed and movable compensators. The fixed compensators include gaskets, filler rings, and similar parts whose dimensions and shape eliminate deviations from nominal dimensions. Fillers that fix the position established for the parts after hardening may also be fixed compensators. Such compensators are used in the production of models and technological attachments.

Movable compensators may have periodic or continuous action. Compensators with periodic action (adjusting screws, eccentric bushings, and so on) eliminate dimensional variations during movement or rotation. Continuous compensators operate automatically; examples are double universal joints that compensate for shaft misalignment (the Hooke’s joint) and bellows that compensate for elongation in pipes.

In machines that operate under various thermal conditions (for example, internal-combustion engines) compensators eliminate the effect of thermal strains; in closed fluid systems (in hydraulically driven machines), constant pressure is maintained by the fluid compensators during temperature changes in the fluid. In electrical engineering a compensator is used to improve the power factor (cos ø) and regulate the voltage in power systems. Compensators are needed for the normal operation of off-axial shafts, to provide the prescribed clearances in supports and gearing, to transmit motion between moving shafts, and to eliminate play in joints. Their use makes possible the general adoption of interchangeable parts and improves the service life and repairability of machines with less accurately made parts. The introduction of compensators into machines makes the mass-production process easier, reduces individual adjustment of parts during assembly, and reduces production and operating expenses.

(2) A thermomagnetic ferroalloy containing 38 percent nickel and 14 percent chromium. It is used in various electrical measuring instruments for shunts on permanent magnets to reduce temperature error.

REFERENCE

Spravochnik mashinostroitelia, 2nd ed., vol. 4. Moscow, 1956.

S. V. BESPALOV and A. I. ZUSMAN