DE3335743C2 - Device for measuring easily deformable objects - Google Patents

Abstract

In a device for measuring the size of easily deformable objects, in particular tumor tissue, with a fixed and a movable probe arm with touch contact ends, the distance between which is displayed on a scale, subjective influences in the scanning measurement are reduced or eliminated by using the touch contact ends as Contact plates (3, 4) are formed and the contact plate (4) provided in particular on the movable probe arm (1) is displaceable relative to the probe arm (1) against an adjustable spring (9) which transmits the pressure force. The presence of the desired contact pressure during the measuring process can either be identified in the simplest embodiment by means of simple marking, but an optical or acoustic signal can also be given through appropriate electrical contacts and / or automatic measured value acquisition can be achieved. Alternatively, when the desired pressure is reached, the feeler arm (1) and contact plate (4) can be locked, for which purpose, in the case of an embodiment that works according to the caliper principle, the spring (9) is bridged by a push rod (20) and a rotary wedge (21) can be (Fig. 5).

Description

The invention relates to a device for measuring the size of easily deformable objects, especially of tumor tissue, with a fixed and a movable probe arm with contact plates, which are movable against each other and their distance is displayed on a scale, the movable Probe arm is connected to its contact plate via a spring and is locked when reading the measured value.

The measurement of rigid bodies with a calliper, micrometer screw or the like is completely unproblematic. In the case of flexible objects made of foam, rubber or the like, on the other hand, the result of a scanning Measurement strongly influenced by the applied pressure. Especially in daily practice the determination of tumor thickness there are great doubts regarding the use of (here mostly forceps-like) Values determined by probe arms, especially if the measurement is carried out by different people usual measuring devices that do not take into account the pressure force.

A precision measuring mechanism for soft materials is already known, in which a relative display of the via a spring preload preselectable contact pressure is provided, which must be observed by the user when reading the measured value (Company brochure "Feinmeßzeuge", 1972, from Mauser-Messzeug GmbH, page 75). However, there is no lock of the measuring mechanism, so that the flexible object can be squeezed together at will if the measuring pressure display is not or not correctly observed.

DE-OS 28 32 986 also discloses a slide caliper with an indicator-triggering stop switch in which a spring element between the contact surface and the feeler triggers a reading of the measured value when a certain "setpoint" of the spring compression is reached, but without an automatic limitation or lock of the contact force would be provided .

DE-OS 30 45 355 finally shows a caliper in which the locking of the slide with a The pawl takes place via a spring, the bias of which is already considerable, so that no serious change is made the contact pressure takes place with further compression. This device also shows no exact limitation the pressure force, but only an arbitrary one Blocking of the slide, whereby after maximum compression of the spring a movement of the Slider on the object to be measured and the application of a constant contact pressure to the sense of touch left to the user The arbitrary lock of the measuring mechanism remains after removal of the measuring object received and is released again by hand

The invention is therefore based on the object of creating a measuring device in which an automatic Locking of the probe arm and contact surface when a desired pressure is reached, so that a any further pressure load on the test object becomes impossible.

This object is achieved by the invention Device of the type mentioned solved, which is characterized by a non-positive lock of the movable probe arm with contact plate when reached the desired contact pressure, which can be adjusted by varying the spring preload

Further particularities emerge from the subclaims.

With this device, a (preselectable) pressure force is automatically maintained during the measurement, which pressure cannot be exceeded, so that an unintentionally higher or lower pressure is avoided when the measured value is recorded.
The invention is described below on the basis of exemplary embodiments with reference to the accompanying drawings; show it (schematically):

F i g. 1 and 2 two variants of a device operating according to the slide caliper principle; and
F i g. 3 a pliers-like thickness gauge looking up.

In Fig. 1 is a thickness measuring device which works essentially according to the caliper principle, in plan view (left) and from the side (right), with the partial figure shown on the left by the calm handling facilitating bracket with return spring fixing, as in F i g. 2 shown, would be supplemented. This Device has a stationary probe arm 1 with a contact plate 2, which is opposite the contact plate 3 of the movable Probe arm is arranged. The latter is essentially due to an extension of the contact plate 3 and a slide rod 4 is formed, which is arranged displaceably in the bracket 5 and by a return spring 6 in each case in the largest contact plate spacing

corresponding rest position is printed. The distance 7 between the contact plates 2 and 3 is displayed on a dial gauge 8 pointing in the direction of the measuring range is arranged, which facilitates the attention or improves the measuring comfort

The contact plate 3 is connected to the dial gauge via the rod 9 and its rear extension extends through a corresponding slot 10 in the slide rod 4 into the groove 11 (behind the slide rod), in which a push rod 12 is movable, one end of which is attached to the extension of the contact plate 3 (possibly adjustable), while the other end is rotatably mounted on an asymmetrical rotating wedge 13 is, which is rotatably connected to the slide rod 4 and when pivoting upwards at the bottom of the groove 11 to Stop is coming.

With the slide rod 4 is firmly connected to the rod 9 encompassing angle 14, which acts as an abutment for the with the knurled nut 15 adjustable spring 16 is used. The knurled nut 15 sits on the rod 9, so that the spring 16 compressed with increasing resistance on the contact plate 3 and the contact plate extension in the slot 10 (in the drawing) is moved upwards, taking along the push rod 12, which the rotary wedge 13 moves until it is stuck on the bottom of the groove 11 This blocks any further "closing movement" of the thickness measuring device and the reading can take place.

As in the case of the pliers-like embodiment according to FIG. 3 are also in the case of FIG. 1 embodiment shown Angled gripping eyes 17 and 18 are provided, of which the eye 18 is on the extension of the bracket 5 and the eyelet 17 is attached to the slide rod 4

The in F i g. The variant shown in FIG. 2 differs from the embodiment according to FIG. 1 only by that the spring 16 with knurled nut 15 on the tapered slide rod 4 is mounted, which is formed by the sliding sleeve rear end of the extension the contact plate 3 is passed through. In this way, the free space is between the contact plate 2 and the top stop of 3 fully available for measurement.

The in F i g. As is customary in medical practice, the arrangement shown in FIG. 3 is designed like pliers with approximately 1 cm ² contact plates 2 and 3, of which the movable plate 3 is slidably arranged with a lock in a sleeve 19 designed with a lock.

With this arrangement there is a certain problem with larger contact plates, if a very large one Measuring range is desired, since the exact measurement value acquisition a parallelism of the opposing Contact plates necessitate a certain inclination the contact plate 3 on the movable arm, so that the contact plates are parallel at half the measuring range or is reached in the area of the most frequently expected measured value, a create some remedy.

Although in the above the limitation of the pressure force by a flexible contact plate on the movable probe arm is described, there is of course also the possibility of this on the other probe arm to be provided.

For this purpose 3 sheets of drawings

65

Claims (5)

Patent claims: 1. Device for measuring the size of easily deformable objects, especially tumor tissue, with a fixed and a movable probe arm with contact plates that can be moved against each other and their distance is displayed on a scale, with the movable probe arm over a spring is connected to its contact plate and is locked when the measured value is read by a non-positive lock of the movable probe arm (3 ', 4) with contact plate (3) when the desired contact pressure is reached, which can be adjusted by varying the spring preload is 2. Device according to claim 1, characterized in that that the movable probe arm (3 ', 4) has a slide rod (4) in a manner known per se, on the contact plate (3) over the helical spring (16) is movably mounted, which when the desired pressure is reached by a non-positive Slide rod lock (It - 13) is bridged. 3. Apparatus according to claim 2, characterized in that the spring (10) between one with the Slide rod (4) connected abutment (14) and the contact plate (3) or a contact plate carrier is mounted, with which one end of a push rod (12) is firmly connected, the other Pivotable end with an asymmetrical one pivotally connected to the slide rod (4) Locking wedge (13) is connected, which comes to a stop on a stationary abutment (5) and the slide rod (4) blocked. 4. Device according to claims 2 or 3, characterized by a return spring (6) for the slide rod (4) to the maximum contact plate spacing. 5. Device according to one of the preceding claims, characterized by of the feeler arms downward angled gripping eyes (17, 18) on the feeler arms (1; 3 ', 4).