v to valves lifter

v to Vaccum metalizing

'V. Volt symbol for valve on circuits.
V's. (Mach. Shop) Ways shaped like a V, either raised or sunken, to serve as a guide for a movable table or
carriage. VA. Volt-ampere.
Vacuum. (Phys.)A space from which the air or any matter has been ex­hausted. (Steam. Heat.) A pump used to cemove condensation and air from the return main of a heat­ing system in order to (a) create a vacuum r.nd (b) return the conden­sate to the boiler or to a receiving tank.
Vacuum brake. (Auto.) A system par­ticularly desirable for heavy pas­
senger cars. The mechanical braking system is operated by a vacuum taken from the intake manifold or carburetor at a point just above the throttle valve.
Vacuum cleaner. A motor-driven fan machine used for sucking up dirt and dust from rugs, etc.
Vacuum control. (Auto.) The term may apply to any automobile de­vices such as brakes, clutch, etc., controlled by manifold vacuum.
Vacuum forming. (Plast.) Also known as sheet forming, and heat forming. An important fabricating operation in which thermoplastic sheet is heated until plastic, when it is clamped into a forming fixture under a frame, and drawn down over a shaped mold by vacuum. There are many variations of the process: some in which sheets are blown upward or downward into molds by air pressure, and some which compensate for the thinning of stretched areas by a step proce­dure. Forming is widely used in display signs (notably for oil sta­tions) and in airplane covers.
Vacuum fuel supply. (Auto.) De­pends upon the use of a vacuum tank to raise the gasoline from the main tank to the higher level of the engine. When the engine is run­ning, a partial vacuum is main­tained in the vacuum tank by uti­lizing the vacuum created at the carburetor.
Vacuum gauge. (Auto.) An instru­ ment calibrated in atmospheric inches to test the vacuum produced in the intake manifold of an engine or in the fuel line.
Vacuum metalizing. (Plast.) A pro­cess by which plastic parts are thinly coated with vaporized metal (aluminium). This is done in a vacuum tank, the vaporizing being accomplished by means of an elec­tric element. The metal is lacquer sprayed to gold, brass. or copperVacuum spark advance to valves lifter assembly colour. Products may also be par­tially metalized.
Vacuum spark advance. (Auto. Elec.) A metal diaphragm connected by a rod to the breaker-point plate. The diaphragm is actuated by the intake manifold vacuum which varies with the throttle opening, causing an ad­ vance of the spark by rotation of the breaker-point plate.
Vacuum tube. (Elec.) An electron tube evacuated to such a degree that its electrical characteristics are essen­tially unaffected by the presence of residual gas or vapour..
Valence. (Chern.) That property pos­sessed by elements of radic;lls of' combining with or repla~ing other elements or radicals in definite and constant proportion.
VaDey. (Arch.) (I) The gutter or angle formed by the meeting of two roof slopes. (2) The space between vault ridges viewed from above.
VaDey rafter. (Arch.) The rafter ex­tending along and under a valley.
Value. (Color) The quality of light­ness or darkness of a colour.
Valve. A device for regulating the flow of a liquid or gas through pipes.
Valve action. (Auto.) Those parts con­trolling the opening and closing of the valves, namely, timing gears, chain, camshaft, valve lifters,
Valve face. (Auto.) The beveled part of the valve head which mates with the valve seat.
Valve keepers. (Auto.) Keys to main­tain the spring tension on the valve stem, usually placed below the spring washer on the valve stem.
Valve lap. (Auto.) The amount of lap between the opening of the intake and the exhaust, indicated by marks on the flyw~eel in degrees or number of teeth. Opening of the intake valve prior to closing of the exhaust valve is called "positive lap". When the intake valve opens after the closing of the exhaust valve it is called "minus lap".
Valve lifter. (Auto.) (I) Same as valve plunger or valve tappet. (2) A hand tool for relieving spring pressure when removing or replacing the valves.
Valves-lifter assembly. (Auto.) The various parts, guides, tappets, ad­
justing screws, etc., which operate between the camshaft and the pop­pet valves to regulate valve action. These parts are sometimes mounted in a housing bolted to the crank­case.