GB689895A - A new or improved hydraulic pressure transmitting device for use in measuring loads or stresses - Google Patents

Abstract

689,895. Dynamometers. BOOTH, C. H. April 12, 1950 [April 12, 1949], No. 9908/49. Class 106 (ii). A flexible capsule having a pipe for transmitting pressures developed therein to a fluid pressure-indicating device, comprises two separately constructed components secured face to face over a narrow area around their periphery, at least one of the components being flexible in a direction perpendicular to its face, both components being of a material capable of resisting deformation in the plane of the faces of the capsule or one component being of such a material and being arranged to constrain the other component against deformation in its own plane, means for applying the force to be measured over the whole surface of the flexible component including the said narrow area at the periphery, and a layer of rubber or like resilient or elastic material acting as a viscous liquid and assisting in the sealing the capsule at said narrow area under the action of the'. oad applying means, the layer of rubber or lie, material comprising or being additional to the flexible component aforesaid. In Fig. 1 the capsule has a rigid base 16 presenting an upstanding peripheral flange 17, the base being slightly dished to form around the internal circumference of the flange a seating 18 for a rubber disc 15. The rubber disc 15 is secured to the seating 18 and the inner wall 19 of the flange 17 by bonding or adhesive. The rubber disc 15 has a diameter normally somewhat greater than the internal diameter of the flange 17 so that in use it presses against the flange 17 to assist in obtaining a seal. The thickness of the rubber is such that it extends above the flange 17 and the force to be measured is distributed by a plate or piston 20 over the whole of the outer face of the rubber disc, thereby applying a pressure between the disc 15 and the seating 18 which is proportional to the applied load to ensure an effective seal. A pipe for transmitting the internal pressure to a pressure gauge is shown at 13. In Fig. 2 a flexible metal disc 22 is disposed between the rubber disc and the base member, the metal disc being soldered to the rim 18. In this case the load may be applied to the rubber disc through a rigid plate 23 sliding within the flange 17. In Fig. 4 the capsule is of annular form. Art annular rubber ring 30 is seated between annular flanges 31, 32 on a non-flexible member 33, each flange having an undercut groove 34 for the reception of the edge of the rubber. An annular plate or piston 36 guided by the flanges 31, 32 acts as the force applying member. Anti-friction members 38 may be provided between the piston 36 and one of the flanges. Specification 672,252 is referred to.