Abstract:
An arrangement for registering pressure fluctuations in a pressure system includes a sensing element which is subjected to the fluctuations of pressure applied thereto by the pressure system. The sensing element is operatively connected with a transmitting element, which transmits signals in response to the fluctuations of pressure sensed by the sensing element. The arrangement is further provided with a register (e.g., a counter), operatively connected to the transmitting element, for registering the pressure fluctuations.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to pressure systems, and more particularly this invention concerns an arrangement for registering pressure fluctuations in pressure systems. 
     Arrangement for registering the pressure fluctuations in pressure systems have already been proposed in the art. 
     However, it was recognized that the prior art arrangements are not satisfactory with respect to registering the fluctuations of pressure in pressure systems, as to the complexity and reliability of such arrangements. 
     SUMMARY OF THE INVENTION 
     It is a general object of the present invention to avoid the disadvantages of the prior art arrangements. 
     More particularly, it is an object of the present invention to provide a reliable and yet very simple arrangement for registering the pressure fluctions in pressure systems. 
     In accordance with an advantageous feature of the present invention it becomes possible to determine in a simple and reliable manner the value of each pressure fluctuation in the mass fluctuations and subsequently summing up the individual values of pressure fluctuations in order to judge the reversal of stresses in the pressure system and consequently to judge the durability of the same. 
     In pursuance of the objects, one feature of the present invention resides in a sensing member which is adapted to be subjected to the fluctuations of pressure applied thereto by a pressure system, transmitting means operatively connected to the sensing member. The transmitting means are operative for producing signals in dependence upon the fluctuations of pressure sensed by the sensing member. 
     According to a further concept of the present invention, the arrangement further comprises means operatively connected to the transmitting means and operative for summing up the individual signals received from the transmitting means. 
     The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     FIG. 1 is a longitudinal sectional view of a sensing member according to the present invention; 
     FIG. 2 is a view of transmitting means of the arrangement, according to the present invention; 
     FIG. 3 is a view of the free-wheeling clutch; and 
     FIG. 4 is a schematic view of a second embodiment according to the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings and first to FIG. 1 thereof, it may be seen, that the reference numeral 10 designates a hollow housing provided with a bore 11, closed at the trailing end of the housing 10 with a cover 15. The housing 10 is further provided at its leading end with a bore 18, communicating the bore 11 with a not-illustrated pressure system, for example a gas or fluid reservoir. The cover 15 is provided with a through-outgoing bore 14. A piston 12 with a piston rod 13 is movably positioned in the bore 11. The piston rod 13 projects with its end through the bore 14 in the cover 15 out of the housing 10. The piston 12 is biased by a spring 16 positioned on the piston rod 13 against a shoulder 17 provided at the leading end of the bore 11. 
     The portion of the piston projecting out of the housing 10 is provided with a rack portion 19, which engages with a pinion 20 mounted on a shaft 21. The shaft 21 connects the pinion 20 through a free-wheeling clutch 22 and a reduction gear element 23 with a register 24, e.g., a counter. 
     Should the piston 12 be subjected to pressure impulses, then the piston will move in the direction to compress the spring 16, to the right as shown in FIG. 1, so that the rack portion 19 of the piston rod 13 will rotate the pinion 20. This movement is transmitted through the free-wheeling clutch 22 and the reduction gear 23 to the register 24, where pressure fluctuations are summed-up in dependence upon the extent of the variations of these fluctuations. Depending upon the extent of the displacement of the piston (back or forth) the register 24 will be advanced by one unit, a fraction of a unit or a plurality of units to be counted. 
     The fluctuations which are within the range of fatigue limit, can be eliminated from registering by placing between the pinion 20 and the register 24 a gear coupling, formed as a free-wheeling clutch, so that indexing corresponding to these fluctuations may be fixed. 
     FIG. 3 shows an embodiment of such a free-wheeling clutch. The clutch 22 consists of two cylindrical bodies, each provided with sawtooth shaped gearing. The second body is movable due to a biasing force of a spring 27. Such a construction of the clutch prevents the register 24 from turning in reverse direction. The tension of the spring 16 can be regulated by screwing or unscrewing the cover 15 into or out of the housing 10 respectively. 
     If only one and the same group of fluctuations is to be determined, separate arrangements are provided each having an individual register. 
     In the embodiment shown on FIG. 4, there are utilized in part electronic structural elements. The reference numeral 30 designates a preferably mechanic-electronic pressure pick-up (pressure switch with actuating member), which can include a power-supply unit, an amplifier, an adder, an integrating register or a function generator. An operating element 31 is connected with electronic register 32, so as to register pressure impulses. 
     The load alteration determined and registered by this arrangement is used for judgement of the durability of an investigated device, according to a corresponding stress-cycle diagram (Woehler-line). Should a volume and a duration of an action of the fluctuations during dynamic stresses be known, then the allowable load alteration of the structural elements can be determined (time and fatigue strength limit). 
     When different fluctuations occur, which follow each other in random succession, the above discussed arrangements serve as a register element controlling in reliable manner the operation of fluid-technique or other systems. Such a control is necessary, because not every structural element of such systems (proceeding from economical grounds) can be constructed to have sufficient fatigue strength. Particularly, it is important to exactly determine load alterations due to fluctuations, which can be judged according to time-fatigue strength limit, in pressure reservoirs and pressure-reservoir devices which accumulate energy. Uncontrollable energy release from reservoir or other structural elements can lead to serious damages. 
     The embodiment, shown in FIG. 4, can readily carry out the integration in accommodation to the Woehler stress-line diagram for non-linear stresses. The arrangement also is suitable (when using an appropriate pressure pick-up, such as for example tensile-strain strip gauges) for registering dynamic stresses of any other types. 
     It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of arrangements differing from the types described above. 
     While the invention has been illustrated and described as embodied in an arrangement for registering pressure fluctuations in a pressure system, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention. 
     Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.