Method of inspecting the dimensional accuracy of medical ampuls

Details Method of inspecting the dimensional accuracy of medical ampuls Method of inspecting the dimensional accuracy of medical ampuls

1993-02-05

1994-07-19

Nelms, David C.

Radiant energy

Photocells; circuits and apparatus

Optical or pre-photocell system

250223B, G01N 2186

Patent

active

053311744

DESCRIPTION:

BRIEF SUMMARY
BACKGROUND OF THE INVENTION

The invention relates to a method for inspecting medical ampuls for dimensional accuracy, wherein the ampuls are held in a horizontal position on a conveying device and are moved in cycles through an inspection station.
Medical ampuls must meet high demands for dimensional accuracy since the quantity filled into them is not measured when the ampuls are filled. Instead, it is assumed that if they are filled to a predetermined fill marker the desired fill level is accurately attained. The fill quantities are generally relatively small, so small dimensional fluctuations signify relatively great changes in the fill quantity. This leads to a correspondingly great fluctuation in the pharmacologically effective dosage for administration of the medications packaged in the ampuls.


SUMMARY OF THE INVENTION

It is the object of the invention to check the dimensional accuracy of medical ampuls automatically and without contact.
According to the invention, accomplished by a method in which: support for inspection and is illuminated by transmitted light from a diffusely radiating illumination source perpendicularly to its longitudinal axis, with the ampul to be examined being rotated about its longitudinal axis if required; the variations in geometry and/or transparency, with this brightness modulation constituting optical information about the measuring parameters; equipped with photodiodes; the ampul or-- in the case where the ampul being examined is rotated about its longitudinal axis-- of a sequence of individual surface strips of the ampul being examined corresponding to a development of the ampul surface; and digital image evaluation unit and are there evaluated with respect to their brightness modulation to the extent that measurement values are generated for the desired ampul dimensions and, if applicable, for their deviations from standard ampul dimension.
The invention is based on the concept of scanning each ampul opto-electronically and digitally evaluating the scanned values. In dependence on the determined dimensional accuracy, the respective ampuls can be positively separated without interruption of production if a fixed tolerance range is exceeded so that the production of rejects can be determined accurately. Additionally, the practically delay-free checking of all ampuls when exceeded tolerances are detected permits immediate access to the tools that produce the medical ampuls, so that production of rejects can be quickly detected and eliminated. With the aid of digital evaluation it is also possible to compile a complete measuring protocol for all ampuls of each production charge as a proof of quality for the purchasers of the ampuls. Moreover, the precision of the manufacturing tools and their service life can also be checked with the aid of the compiled measuring protocols.


BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in greater detail with reference to embodiments thereof that are illustrated in the drawings, in which:
FIG. 1A is a view of a so-called one-point-cut (OPC) ampul in the empty state in which the axially symmetrical position of a colored marker and the position of a scratch mark serving as an intended break location relative to the colored marker constitute special inspection parameters in addition to the outline dimensions of the ampul;
FIG. 1B is a detail view of the OPC ampul of FIG. 1a in the region of the colored marker;
FIGS. 2A, 2B, and 2C are views of various ampul shapes according to DIN [German Industrial Standard] 58,377 to illustrate the outline dimensions to be examined;
FIG. 3 is a schematic representation of a device composed of two inspection stations for implementing the method according to the invention;
FIG. 4 is a front view of an inspection station for checking outlines as provided in the inspection apparatus of FIG. 3;
FIG. 5 is a side view of the inspection station of FIG. 4;
FIG. 6 is a front view of a further inspection station for monitoring the colored marker and the scratch mark on OPC ampuls provided

REFERENCES:
patent: 2857038 (1958-10-01), Noble et al.
patent: 3458967 (1969-08-01), Ziche
patent: 4367405 (1983-01-01), Ford
patent: 4483615 (1984-11-01), Bieringer et al.
patent: 4549205 (1985-10-01), Misaki et al.
patent: 4725856 (1988-02-01), Fujikura
patent: 4731649 (1988-03-01), Chang et al.
patent: 4912318 (1990-03-01), Kajiura et al.
patent: 4975568 (1990-12-01), Taniguchi et al.

Affiliated with

Also associated with

Rating

Method of inspecting the dimensional accuracy of medical ampuls does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method of inspecting the dimensional accuracy of medical ampuls, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of inspecting the dimensional accuracy of medical ampuls will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-521753