GB883295A - Improvements in frusto conical diaphragms - Google Patents

Abstract

883,295. Diaphragm pistons. MOULTON DEVELOPMENTS Ltd. Oct. 6, 1958 [Aug. 15, 1957; Dec. 30, 1957], Nos. 25818/57 and 40345/57. Class 122 (1). [Also in Group XXXII] In a method of constructing a flexible diaphragm or rubber-like material reinforced with cord fabric, one or more circular blanks of rubberized cord fabric having parallel cords are cut and wrapped in such a manner that a fabric cone is obtained in which the cords overlap symmetrically. Semi-circular pieces 1, 2, Fig. 1, of parallel cord fabric are cut with the cords 3 parallel to a diameter 4. These pieces are wrapped into cones. Two or more of these cones are then superimposed, Fig. 3, to give a structure in which the cords cross everwhere at right angles as shown at 5. The included angle of the cone is 60 degrees. In an alternative form of construction, a circular blank 6, Fig. 5, of rubberized fabric having cords 7 is cut radially along the line of cords as at 8. The blank is then folded round three times to form a three-ply truncated cone with an included angle of approximately 39 degrees, the cut edges of the blank being secured parallel to one another, one inside and one outside the cone on the same radius. In this construction the cords cross one another at an angle of 60 degrees. In a third construction, two circular blanks of rubberized cord fabric are each cut as in the method above described and are each folded one and half times in such manner that each forms a truncated cone having an included angle of approximately 84 degrees. The cones are then assembled one inside the other so as to form a three-ply construction. The cut edge of the inner side of the outer cone is parallel to and on the same radius as the outer cut edge of the inner cone, and the outer cut edge of the outer cone is diametrically opposite to the inner edge of the inner cone. The plies cross one another at 60 degrees. A bead wire may be incorporated in the outer edge of all the cones described. A conical metal insert 21, Fig. 12, may be moulded into the diaphragms constructed as above. A skin of sealing rubber 23 is placed on the inner surface of the diaphragm and a butyl liner 24 is also provided. A stud 25 attached to the metal insert serves to locate the diaphragm in use. Specification 870,489 is referred to.