PROCESS FOR THE CLEANING AND HEAT TREATMENT OF SURGICAL NEEDLES

Abstract: In a process for the cleaning and heat treatment of surgical needles, the surgical needles to be treated are placed in a basin (1) having an upright edge (5, 7) which is covered on its inside at least in its lower region by a frame (10) inserted into the basin (1). The surgical needles are then cleaned in the basin (1), the frame (10) being inserted, with the help of a washing or cleaning liquid. Before the surgical needles in the basin (1) are subjected to a heat treatment, the frame (10) is removed from the basin (1).

Description: Process for the cleaning and heat treatment of surgical needles The invention relates to a process for the cleaning and heat treatment of surgical needles . In the manufacture of surgical needles there are processes in which the needles are first shaped from relatively soft metal and are later hardened at increased temperature. In the course of such processes a recess is drilled into the end-side of a given needle lying opposite the tip of the needle, prior to the heat treatment. This recess serves for the subsequent securing of a surgical thread. After the drilling the surgical needles are cleaned with the help of a washing or cleaning liquid and then dried. Finally, the already mentioned heat treatment takes place, e.g. in an oven at ca . 1000°C. In such a process it is customary to place a number of the surgical needles to be treated in a basin (preferably made from metal) and clean them, dry them and subject them to heat treatment in the basin. However, needle tips which touch the walls of the basin are easily damaged during the heat treatment, as they are forced against the walls (the edge) of the basin by the thermal expansion of the surgical needles while in a soft, red-hot state. - 2 - The object of the invention is to improve the previously mentioned process for the cleaning and heat treatment of surgical needles in such a way that the surgical needles to be treated are not damaged during the heat treatment by the basin in which they are placed. This object is achieved by a process for the cleaning and heat treatment of surgical needles having the features of claim 1. Advantageous versions emerge from the dependent claims . In the process according to the invention for the cleaning and heat treatment of surgical needles, the surgical needles to be treated are placed in a basin with an upright edge. The edge is covered on its inside at least in its lower region by a frame inserted into the basin. The surgical needles are then cleaned in the basin, with the frame inserted, by means of a washing or cleaning liquid. Before the surgical needles are heat treated in the basin, e.g. at ca. 1000°C in an oven, the frame is removed from the basin. This results in the needles lying at an adequate distance from the edge of the basin during the heat treatment. This distance is at least as great as the thickness of the frame. The frame is preferably dimensioned in such a way that the gap between the edge of the basin and the frame is relatively narrow when the frame is inserted into the basin, with the result that, when the surgical needles are poured into the basin, the needles cannot directly enter the gap and then rest against the edge of the basin in an undesirable manner. - 3 - In a preferred version of the invention, the surgical needles are dried in the basin in a separate step prior to the heat treatment, preferably prior to the removal of the frame from the basin. This results in the frame also preventing a contact between the needles and the edge of the basin during the step for drying of the surgical needles . A basin is preferably used which is fitted with run-off openings for the washing or cleaning liquid. Such a basin can be made from a sheet with an upwardly bent edge, at least one of the border regions between adjacent edge parts not being closed. Such a basin with a rectangular bottom surface can easily be produced by bending four edge parts upwards and also has the advantage that it does not buckle during the heat treatment. The process according to the invention is described in more detail below with reference to an embodiment. The drawings show Figure 1 a plan view of a basin in which the surgical needles to be treated are placed, a frame being inserted into the basin, Figure 2 a longitudinal section through the basin with inserted frame along the line A-A in Figure 1 and Figure 3 a side view of the basin with inserted frame. _ 4 _ In Figures 1 to 3 a basin 1 is represented in which the surgical needles to be treated are placed when carrying out the process according to the invention. The basin 1 has a bottom 2 and an upright edge which consists of four edge parts 4, 5, 6 and 7 which form the side walls of the basin 1. In the embodiment, the basin 1 is made in one piece from a heat-resistant metal sheet, the edge parts 4, 5, 6 and 7 being bent upwards at the periphery of the bottom 2. The border regions 8 between any two neighbouring edge parts 4 , 5 , 6 or 7 are not closed. This results in the basin 1 not warping, or warping only slightly, at high temperature. Moreover, the washing or cleaning liquid used for cleaning the surgical needles placed in the basin 1 can run off from the basin 1 via the border regions 8. As can be seen from Figures 1 to 3, a frame 10 is inserted into the basin 1 from above. In the embodiment, the frame is rectangular and made from a plastic material which is resistant to the washing or cleaning liquid used for cleaning. The frame is dimensioned in such a way that its upper region 11 protrudes above the edge parts 4, 5, 6 and 7, see Figure 2 and Figure 3. This makes it possible to remove the frame 10 without problems from the basin 1. The gap 12 between the insides of the edge parts 4, 5, 6 and 7 and the outside of the frame 10 is relatively narrow in the embodiment, see Figure 1 and Figure 2 . The gap 12 is large enough to guarantee an easy insertion of the - 5 - frame 10 into the basin 1. On the other hand it is so narrow that, when surgical needles to be treated are poured into the basin 1, the probability that a needle will fall into the gap 12 is small. In the following, the steps which occur when carrying out the process according to the embodiment are explained. In the manufacture of surgical needles, the needles are first shaped so that they each receive a needle tip and an end-side lying opposite the needle tip. A hole, in which the front end of a surgical thread is later secured, is drilled into the end- side of a given needle. A plurality of surgical needles prepared in this way are then placed in a basin 1 fitted with a frame 10. The frame 10 prevents the needles from touching the edge parts 4, 5, 6 and 7 of the basin 1. The basin 1, with the frame 10 and the surgical needles located in the basin 1, is then immersed in a bath which contains a washing or cleaning liquid. It is possible to move the basin 1 in the bath, as the washing or cleaning liquid can flow into the basin 1 or leave the basin 1 via the border regions 8 between the edge parts 4, 5, 6 or 7. Alternatively, washing or cleaning liquid can be poured into the basin 1 from above, in which case used liquid flows away via the open border regions 8. During the - 6 - cleaning, the basin 1 with the surgical needles located in it can be moved or shaken in order to support the process; the frame 10 reliably prevents the needles from touching the edge parts 4, 5, 6 and 7 of the basin 1. In a subsequent process step, the surgical needles are dried in the basin 1. The frame 10 remains in the basin 1, with the result that the needles cannot come into contact with the edge parts 4, 5, 6 and 7 even if they are shifted in the basin 1 during drying . Before the surgical needles located in the basin 1 are subjected to a heat treatment, the frame 10 is pulled up out of the basin 1. The basin 1 should no longer be exposed to strong vibrations thereafter, so that the needles 1 do not move to the edge parts 4, 5, 6 and 7. The heat treatment of the surgical needles is then carried out in an oven, at ca . 1000°C in the embodiment, in order to achieve a hardening of the surgical needles. During this step, the needles are located in the basin 1 which is made from heat- resistant material. After the heat treatment has ended, the surgical needles can be removed from the basin 1. Other processes, e.g. for the treatment of the needle surfaces or for the securing of surgical threads, can be added.

Claims: - 7 - Claims 1. Process for the cleaning and heat treatment of surgical needles, with the steps: - placing of the surgical needles to be treated in a basin (1) having an upright edge (4, 5, 6, 7) which is covered on its inside at least in its lower region by a frame (10) inserted into the basin (1), - cleaning of the surgical needles in the basin (1), the frame (10) being inserted, with the help of a washing or cleaning liquid, - removal of the frame (10) from the basin (1), - heat treatment of the surgical needles in the basin (1). 2. Process according to Claim 1, characterized in that the surgical needles are dried in the basin (1) in a separate step prior to the heat treatment. 3. Process according to Claim 2, characterized in that the surgical needles are dried prior to the removal of the frame (10) from the basin (1). 4. Process according to one of the previous claims, characterized in that a basin (1) is used which is fitted with run-off openings (8) for the washing or cleaning liquid. - 8 - Process according to Claim 4, characterized in that a basin ( 1 ) is used which is made from a sheet with an upwardly bent edge (4, 5, 6, 7), at least one of the border regions (8) between adjacent edge parts (4, 5, 6, 7) not being closed.

Inventors: GELAHR STEPHAN, STEINER WILFRIED, GELAHR, STEPHAN, STEINER, WILFRIED
Applicants: ETHICON GMBH, GELAHR STEPHAN, STEINER WILFRIED, ETHICON GMBH & CO. KG, GELAHR, STEPHAN, STEINER, WILFRIED
Application year: 1999
Main classification: A61B17
IPC codes: A61B17, A61B19, C21D9