Dual pressure range valve for alternately providing high pressure and low pressure fluid over a single line, the valve including a body having a high pressure fluid inlet port and a low pressure fluid inlet port, BALANCING VALVESboth the inlet ports being alternately communicable with a fluid outlet port. Communication of the fluid outlet port with the high pressure or low pressure fluid inlet port is established by the positioning of reciprocable means mounted within the valve body.Reducing Valves Conventional apparatus for powering such low load long distance and high load-short distance travel of machine components ordinarily comprise hydraulic systems which provide a high volume of low pressure fluid and low volume of high pressure fluid to the machinery being served. In some apparatus the high pressure and low pressure fluids are introduced to the served machinery through separate fluid systems.Bellows Seal Valves Other apparatus introduce a high volume of high pressure fluid to the served apparatus, whereafter the pressure of a great portion of the fluid is reduced for providing the necessary high volume of low pressure fluid. The former approach, i.e. separately introduced high and low pressure fluids, has been found to be undesirable since the served machinery must be structured to accommodate each of the separately introduced high and low pressure fluids. The latter approach, i.e. the introduction of a large volume of high pressure fluid, also has been found to be undesirable in that the provision of such a large volume of high pressure fluid is fundamentally inefficient and difficult to accommodate, and the subsequent pressure reduction requires complex apparatus. Accordingly, those skilled in the art have directed their attention to providing fluid, at high or low pressures as required, to machinery being served through a single source line. The dual pressure range valve of the present invention may be used in any hydraulic system wherein high pressure fluid from one source and low pressure fluid from a second source must be provided alternately through a single fluid line. Many hydraulically operated machines have such a requirement, typical of such machines being punch presses which are used for punching holes in metal blanks. Accordingly, the dual pressure range valve of the present invention will be described below in use with such a machine for purposes of illustration, it being recognized that the valve may be used with many other machines having similar hydraulic fluid requirements. It will be understood by those skilled in the art that the above-described embodiments of dual pressure range valves may be manufactured by known processes and that they are representative of many dual pressure range valves which may be structured in accordance with the teaching of the present invention. Manifestly, many modifications and adaptations may be made in the present invention without departing from the spirit and the scope thereof.

MORE NEWS