Abstract: The measuring instrument for a pressure gauge comprises an indicator unit with two plates that bear rotatably an indicator shaft carrying a pinion and that furthermore bear a gear segment. The measuring instrument furthermore comprises a metal Bourdon tube bent into an arc shape, which is soldered on one end to a spring carrier and on the other to a spring end-piece. The spring end-piece is connected to the gear segment such that the displacement of the spring end-piece because of the measurement pressure is transferred to the gear segment. The spring end-piece constitutes a part that is rigidly attached to one of the two plates prior to the Bourdon tube being soldered to the spring end-piece and that is separated from this plate once the Bourdon tube has been soldered to the spring end-piece. During the course of the manufacture of this measuring instrument, the spring end-piece is produced as a part that is securely joined to the two plates.

Abstract: The measuring instrument for a pressure gauge comprises an indicator unit with two plates that bear rotatably an indicator shaft carrying a pinion and that furthermore bear a gear segment. The measuring instrument furthermore comprises a metal Bourdon tube bent into an arc shape, which is soldered on one end to a spring carrier and on the other to a spring end-piece. The spring end-piece is connected to the gear segment such that the displacement of the spring end-piece because of the measurement pressure is transferred to the gear segment. The spring end-piece constitutes a part that is rigidly attached to one of the two plates prior to the Bourdon tube being soldered to the spring end-piece and that is separated from this plate once the Bourdon tube has been soldered to the spring end-piece. During the course of the manufacture of this measuring instrument, the spring end-piece is produced as a part that is securely joined to the two plates.

Abstract: The measuring instrument for a pressure gauge comprises an indicator unit (2) with two plates (4, 6) that bear rotatably an indicator shaft (24) carrying a pinion (28) and that furthermore bear a gear segment (32). The measuring instrument furthermore comprises a metal Bourdon tube (48) bent into an arc shape, which is soldered on one end to a spring carrier (40) and on the other to a spring end-piece (54). The spring end-piece (54) is connected to the gear segment (32) such that the displacement of the spring end-piece (54) because of the measurement pressure is transferred to the gear segment (32). The spring end-piece (54) constitutes a part that is rigidly attached to one of the two plates (4, 6) prior to the Bourdon tube (48) being soldered to the spring end-piece (54) and that is separated from this plate once the Bourdon tube (48) has been soldered to the spring end-piece (54).

Abstract: In a measurement system for a pressure gage which has a bourdon tube spring as well as a spring support, the bourdon tube spring is made of a metallic material and the spring support is made of a polymer plastic. The connection between the bourdon tube spring and the spring support is made by means of a metallic transition element which has a recess into which the fixed end of the bourdon tube spring is glued or soldered, and which has engagement means formed on it which are in form-fitting engagement with the spring support. The compound assembly comprising the transition element and the spring support combines the cost advantage of the fabrication of the spring support from plastic with the mechanical advantages and antileak advantages of a metal-to-metal connection for the connection of the bourdon tube spring to the spring support.

Abstract: A method of making a tube spring manometer measurement system is disclosed. The system, comprising a tube spring, display assembly and at least one operating member which actuates said display assembly, e.g. a tie rod, is mounted and assembled to form a functional assembly. A predetermined reference pressure is then applied to the tube spring. The deflection of the display assembly caused by said reference pressure is compared to a theoretical deflection. If the difference between a theoretical deflection associated with said reference pressure and the observed actual deflection is excessive, local heat is supplied by means of a laser beam to at least one operating member and/or said tube spring, thereby removing material and/or altering the internal tension thereof. These changes are utilized to influence the range and/or zero baseline of the instrument.

Abstract: A liquid-filled pressure gauge comprising a cup-shaped housing in which a metering element is located whose interior is subjected to the pressure to be measured. The front side of said housing is covered by a stiff face plate on whose inner side a transparent, resilient membrane is disposed in spaced relation which seals off the interior of said housing and which is deflected during temperature-related changes in the volume of the liquid filling. The space between the membrane and the face plate is vented externally. The transparent membrane ensures pressure compensation in the interior of the housing, while the stiff face plate protects the pressure gauge from damage to the front.