A system for measuring the position of a rod element as, for example, a hydraulically or pneumatically operated piston rod. Unlike the prior art, the system according to the present invention employs a measuring principle that does not require preparatory treatment of the rod element as is required in the known solutions. The system employs direct time of flight measurements with the aid of acoustic surface waves that are introduced into the rod element. The instrument is retrofittable on existing cylinders without any modification/reconstruction thereof. An EMAT principle is employed to introduce the surface waves into the measurement in a non-contact manner.
F15B 15/28 - Means for indicating the position, e.g. end of stroke
F15B 19/00 - Testing fluid-pressure actuator systems or apparatus, so far as not provided for elsewhere
G01D 5/48 - Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using wave or particle radiation means
G01S 15/02 - Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems using reflection of acoustic waves
The present invention relates to system for measuring pressure and temperature based on change in the characteristic properties of a medium for ultrasound under the effect of pressure and temperature. The invention is based on two waveguides where geometry is adapted to the medium's characteristic properties for ultrasound such that only planar pressure waves are generated in the waveguides. The first of the waveguides is arranged for measuring temperature due to thermal expansion of the medium, where the medium is pressure-compensated by means of an internal compensator to prevent thermal pressure accumulation, and where measuring temperature is based on the medium's specific known characteristic data for ultrasound under the effect of temperature under constant pressure. The second waveguide is arranged for measuring pressure, based on waveguide and the medium's known characteristic properties for thermal expansion and pressure, and where the thermal effect is corrected analytically based on measurement of temperature in the first channel. The physical principle of the invention is based on the properties of a medium (oil) where the stability for high temperature and pressure is crucial for long-term properties. Long-term properties of ultrasound sensors are not physically linked to the medium's properties, such that change in characteristic properties of ultrasound sensors does not impair the accuracy of the medium unless the function of the ultrasound sensors ceases. The physical principle of the invention allows an arrangement where ultrasound sensors can be separated from measuring channels by a pressure barrier, such that the integrity of the pressure barrier is not broken.
G01L 19/00 - MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE - Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
G01N 29/036 - Analysing fluids by measuring frequency or resonance of acoustic waves
G01N 29/32 - Arrangements for suppressing undesired influences, e.g. temperature or pressure variations
3.
Voltage-free connector integrated in a weapon rail
A universal rail for a firearm has a plurality of through holes and a plurality of attachment points for ancillary equipment along a length of the universal rail, a fastener so as to be fastenable to the firearm, and a power or signal connection point arranged in at least one attachment point of the plurality of attachment points. The power or signal connection point has at least two contact pins surrounded by a seal, and a resilient portion and inner contact faces. The power or signal connection point is further connected to conductors arranged in the universal rail. The resilient portion ensures that the at least two contact pins and contact points are out of contact with each other when the ancillary equipment is not mounted on the universal rail.
b) of the electric motor (31). The electric motor is an electric rotary motor. The invention also relates to a pump assembly with a plurality of such driving arrangements.
F04B 49/20 - Control of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for in, or of interest apart from, groups by changing the driving speed
H02K 7/06 - Means for converting reciprocating motion into rotary motion or vice versa
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