DD242289A1

DD242289A1 - THREE-DIMENSIONAL ACCELERATOR

Info

Publication number: DD242289A1
Application number: DD28262485A
Authority: DD
Inventors: Winfried Gehmlich; Klaus Roeger
Original assignee: Barkas Werke Veb
Priority date: 1985-11-08
Filing date: 1985-11-08
Publication date: 1987-01-21

Abstract

Die Erfindung betrifft einen dreidimensionalen Beschleunigungsaufnehmer mit einer seismischen Masse, die ueber mindestens ein Federelement in einem Aufnehmergehaeuse aufgehaengt ist. Ziel der Erfindung ist es, eine verbesserte Messwertaufnahme gegenueber bekannten Beschleunigungsaufnehmern zu realisieren. Dabei wird die Aufgabe geloest, einen Messwertaufnehmer zur Erfassung von Beschleunigungs- und Verzoegerungswerten raeumlich bewegter Versuchsobjekte mittels Dehnungsmessstreifen zu schaffen. Der erfindungsgemaesse Beschleunigungsaufnehmer umfasst ein Aufnehmergehaeuse, in welchem drei Federringe und eine seismische Masse ineinander aufgehaengt sind. Dabei ist die geometrische Zuordnung der Elemente Federring, seismische Masse und Dehnungsmessstreifen sowie die Ausgestaltung der Verbindungsstellen zwischen diesen festgelegt. Fig. 2The invention relates to a three-dimensional accelerometer with a seismic mass, which is suspended over at least one spring element in a Aufnehmergehaeuse. The aim of the invention is to realize an improved measured value recording compared to known accelerometers. The task is solved to create a transducer for detecting acceleration and Verzoegerungswerten spatially moving test objects by means of strain gauges. The acceleration sensor according to the invention comprises a transducer housing in which three spring washers and a seismic mass are suspended in one another. The geometric assignment of the elements spring ring, seismic mass and strain gauges and the design of the connection points between them is set. Fig. 2

Description

embodiment

Der prinzipielle Aufbau eines erfindungsgemäßen Beschleunigungsaufnehmers ist in der Zeichnung dargestellt und wird nachfolgend beschrieben. Es zeigen:The basic structure of an acceleration sensor according to the invention is shown in the drawing and will be described below. Show it:

Fig. 1: eine Schnittdarstellung des Beschleunigungsaufnehmers in der xz-Ebene Fig.2: eine Schnittdarstellung in deryz-Ebene, Fig.3: eine Schnittdarstellung in der xy-Ebene.1: a sectional view of the acceleration sensor in the xz plane FIG. 2: a sectional view in the yyz plane, FIG. 3: a sectional view in the xy plane.

Der in.der Zeichnung dargestellte Beschleunigungsaufnehmer besteht aus einem Aufnehmergehäuse 1. Ein erster, äußerer Federring 2 ist an zwei gegenüberliegenden Punkten 11; 12 des Aufnehmergehäuses 1 befestigt. Senkrecht zu diesem äußeren Federring 2 ist an zwei Punkten 21; 22 seiner Innenkontur ein zweiter, mittlerer Federring 3 befestigt, wobei dessen Außendurchmesser dem Innendurchmesser des äußeren Federringes 2 entspricht. Senkrecht zum äußeren 2 und mittleren Federring 3 ist an zwei Punkten 31; 32 der Innenkontur des mittleren Federringes 3 ein dritter, innerer Federring 4 befestigt. Der Außendurchmesser dieses Federringes 4 entspricht dabei dem Innendurchmesser des mittleren Federringes 3. An der Innenfläche des inneren Federringes 4 ist an zwei, zu den Verbindungspunkten 31; 32 zwischen mittlerem 3 und innerem Federring 4 jeweils 90" versetzten Punkten 41; 42 eine seismische Masse 5 aufgehängt. Die seismische Masse 5 ist im gemeinsamen Mittelpunkt der drei Federringe 2; 3; 4 angeordnet. An den Verbindungspunkten 21; 22 sowie 31; 32 zwischen den Federringen 2; 3; 4 sind jeweils an der Außenkontur des Federringes 2 bzw/3 Dehnungsmeßstreifen 23; 24 sowie 33; 34 angeordnet. Weitere Dehnungsmeßstreifen 43; 44 sind an den Verbindungspunkten 41; 42 zwischen innerem Ring 4 und seismischer Masse 5 an der Außenkontur des Federringes 4 vorgesehen. Die Dehnungsmeßstreifen 23; 24; 33; 34; 43; sind mit einer in der Zeichnung nicht näher dargestellten elektronischen Schalteinrichtung zur Auswertung der Meßwerte verbunden. Das Aufnehmergehäuse 1 wird zunächst fest mit dem Versuchsobjekt verbunden. Wird das Versuchsobjekt nunmehr beispielsweise in x-Richtung beschleunigt, so wird der innere Federing 4 infolge der Massenkraft der seismischen Masse 5 am Punkt 41 stärker gekrümmt als am Punkt 42 und somit der Dehnungsmeßstreifen 43 gestreckt und der Dehnungsmeßstreifen 44 gestaucht. Die Dehnungsmeßstreifen 23; 24 sowie 33; 34 werden in diesem Moment jeweils gleichläufig belastet, so daß sich deren Meßwerte gegenseitig aufheben. Die den unterschiedlichen Verformungen der beiden Dehnungsmeßstreifen 43,44 entsprechenden elektrischen Signale werden über die elektronische Schalteinrichtung als Maß der Beschleunigung des Versuchsobjektes in x-Richtung ausgewertet. Bei einer Beschleunigung in y-Richtung wirkt gleichartig wie für die x-Richtung beschrieben der äußere Federring 2 mit den Dehnungsmeßstreifen 23; 24 sowie in z-Richtung der mittlere Federring 3 mit den Dehnungsmeßstreifen 33; 34.The accelerometer shown in the drawing consists of a pickup housing 1. A first, outer spring ring 2 is at two opposite points 11; 12 of the transducer housing 1 attached. Perpendicular to this outer spring ring 2 is at two points 21; 22 of its inner contour a second, middle spring ring 3 is fixed, wherein the outer diameter corresponds to the inner diameter of the outer spring ring 2. Perpendicular to the outer 2 and middle spring ring 3 is at two points 31; 32 of the inner contour of the middle spring ring 3, a third, inner spring ring 4 attached. The outer diameter of this spring ring 4 corresponds to the inner diameter of the middle spring ring 3. On the inner surface of the inner spring ring 4 is at two, to the connection points 31; 32 between middle 3 and inner spring ring 4 each 90 "offset points 41, 42 suspended a seismic mass 5. The seismic mass 5 is arranged in the common center of the three spring rings 2, 3, 4. At the connection points 21, 22 and 31, 32nd 2 or 3 strain gauges 23, 24 and 33, 34 are respectively arranged on the outer contour of the spring ring 2. Further strain gauges 43, 44 are connected at the connecting points 41, 42 between inner ring 4 and seismic mass 5 the outer contour of the spring ring 4. The strain gauges 23, 24, 33, 34, 43 are connected to an electronic switching device (not shown in detail in the drawing) for evaluating the measured values, and the sensor housing 1 is first firmly connected to the test object now for example accelerated in the x-direction, the inner Federing 4 due to the inertial force of the seismic mass 5 at the point 41 st curved than at the point 42 and thus the strain gauge 43 stretched and the strain gauge 44 compressed. The strain gauges 23; 24 and 33; 34 are each loaded in the same direction at this moment, so that their measured values cancel each other out. The electrical signals corresponding to the different deformations of the two strain gauges 43, 44 are evaluated via the electronic switching device as a measure of the acceleration of the test object in the x direction. When accelerating in the y-direction acts the same as described for the x-direction of the outer spring ring 2 with the strain gauges 23; 24 and in the z-direction of the middle spring ring 3 with the strain gauges 33; 34th

Durch Anwendung des erfindungsgemäßen Aufnehmers können mit geringem Meß- und Steueraufwand Beschleunigungs- und Verzögerungswerte räumlich bewegter Versuchsobjekte ermittelt werden. Dabei verlaufen die Meßachsen der drei Raumebenen vorteilhaft durch einen Punkt, so daß weitgehend genaue Meßergebnisse realisierbar sind.By using the transducer according to the invention, acceleration and deceleration values of spatially moved test objects can be determined with low measurement and control effort. The measuring axes of the three spatial planes advantageously extend through a point, so that largely accurate measurement results can be realized.

Claims

Invention claim:

A three-dimensional acceleration sensor, comprising a sensor housing with a seismic mass which is suspended via at least one spring element clamped in the housing and at least one strain gage connected to an electronic switching device being arranged on the spring element, characterized in that a first, outer spring washer (2) attached to two opposite points (11; 12) of the transducer housing (1), a second, at two points (21; 22) of the inner contour of the first spring ring (2) fixed middle spring ring (3) perpendicular to the first spring ring (2) and a third, at two points (31; 32) of the inner contour of the middle spring ring (3) mounted inner spring ring (4) perpendicular to the outer (2) and middle spring ring (3) is arranged and in the common center of the three spring rings (2; 4) arranged seismic mass (5) at two, to the connection points (31; 32) between middle (3) and inner Spring ring (4) each 90 ° offset points (41; 42) on the inner surface of the inner spring ring (4) is suspended, wherein in each case in the region of the connection points (21; 22; 31; 32; 41; 42) between the spring rings (2; 3; 4) with each other or between inner spring ring ( 4) and seismic mass (5) on the outer contour of the respective outer spring ring (2; 3; 4) strain gauges (23; 24; 33; 34; 43; 44) are arranged.

For this 1 page drawings

Field of application of the invention

The invention relates to a three-dimensional acceleration sensor, comprising a transducer housing with a seismic mass, which is suspended via at least one spring element clamped in the housing and wherein on the spring element at least one connected to an electronic switching device strain gauges is arranged. The transducer according to the invention is suitable for detecting triaxial acceleration and deceleration values of different types of spatially moved test objects.

Characteristic of the known technical solutions

The detection of accelerations and decelerations of spatially moved test objects is necessary in many fields of technology. Such measurements are carried out, for example, in vehicle technology for triggering occupant protection devices in the event of an accidental collision or for investigations of the passive safety of motor vehicle parts by means of impact test devices. Arrangements have already been proposed in which all three components of the acceleration vector can be detected. Thus, DE-OS 2432225 describes an arrangement with at least three accelerometers, which are held by a holder to form a common intersection point in a spatial system. However, despite the common axis intersection of the transducers, measurement errors can not be ruled out with this arrangement, which is used in particular for installation in experimental manikins for accident investigations, since the components of the acceleration vector are detected at different, relatively widely spaced points. Furthermore, DD-PS 209288 discloses an arrangement for inertial navigation measurements with only one inertial mass. The inertial mass is kept floating in a spatial arrangement by attitude control systems and allows the determination of the three acceleration components of a point. However, a disadvantage is the required measurement and control costs. In addition, this arrangement is only conditionally suitable for investigations in vehicle technology, since at least in hard collisions accurate data acquisition is not guaranteed.

Object of the invention

In an accelerometer of the type described above, an improved data acquisition is to be achieved.

Explanation of the essence of the invention

The object of the invention is to provide an accelerometer with a resiliently suspended at least one spring element in the transducer housing seismic mass, which allows detection of acceleration and deceleration values spatially moving test objects with only a small measurement and control effort by means of strain gauges.

This object is achieved by a first outer spring ring attached to two opposite points of the pickup housing, a second, at two points the inner contour of the first spring ring mounted middle spring ring perpendicular to the first spring ring and a third, at two points the inner contour of the middle spring ring attached inner spring ring is arranged perpendicular to the outer and middle spring ring and the arranged in the common center of the three spring rings seismic mass at two, to the connection points between the central and inner spring ring each offset by 90 ° points on the inner surface of the inner spring ring is suspended, each in the area the connection points between the spring rings and seismic mass are arranged on the outer contour of the respective outer spring ring strain gauges.

The transducer according to the invention enables a largely accurate determination of the acceleration of spatially moved test objects. The measuring axes of the three components of the acceleration vector run exactly through a point.