| 摘要 |
<p>An external air valve for a reciprocating air motor is provided with a the ability to transfer heat from incoming compressed air into the valve cups to prevent icing and a low friction mechanism for the valve slide to enhance reliability. The design has a housing which forms an air chamber, and located in the air chamber is a slide member containing two cups which alternately cover ports leading to the upper and lower chambers of the air motor piston. The slide has slotted rollers to reduce pneumatic loading and decrease friction during sliding. The shift rod is provided with a central valve spring located in an aperture in the slide, along with spring retaining plates to provide and assist in shifting the valve in conjuction with a detent to assure that the valve is positioned in one of two operating positions. The pressurized chamber, in conjunction with fins, apertures and other heat transfer apparatus in the slide assures that heat is applied to the cups of the slide in order to prevent icing.</p> |
