AUTOCLAVABLE ELECTRONICS UNIT FOR AN ENDOSCOPE, METHOD FOR PRODUCING AN AUTOCLAVABLE ELECTRONICS UNIT AND ENDOSCOPE

Abstract

An autoclavable electronics unit for an endoscope, the autoclavable electronics unit including: a multi-layer printed circuit board having a rigid region and a flexible region, the rigid region being reinforced by stiffener material to have a greater rigidity than the flexible region and the flexible region is configured to be bendable. Where the multi-layer printed circuit board is formed from structured layers made of conductive and non-conductive materials adhered together, in which the conductive structures form conductor tracks and contact surfaces; the rigid region is provided with one or more electronic components; and the rigid region is covered by an epoxy resin.

Claims

1. An autoclavable electronics unit for an endoscope, the autoclavable electronics unit comprising: a multi-layer printed circuit board having a rigid region and a flexible region, the rigid region being reinforced by stiffener material to have a greater rigidity than the flexible region and the flexible region is configured to be bendable; wherein the multi-layer printed circuit board is formed from structured layers made of conductive and non-conductive materials adhered together, in which the conductive structures form conductor tracks and contact surfaces; the rigid region is provided with one or more electronic components; and the rigid region is covered by an epoxy resin.

2. The autoclavable electronics unit for an endoscope according to claim 1, wherein the stiffener material is a stiffening plate or one or more stiffening layers

3. The autoclavable electronics unit for an endoscope according to claim 1, wherein the resin contains a ceramic powder

4. The autoclavable electronics unit for an endoscope according to claim 1, wherein the covering is produced by injecting or casting the epoxy resin around the rigid region.

5. The autoclavable electronics unit for an endoscope according to claim 4, wherein the covering has a homogeneous layer thickness.

6. The autoclavable electronics unit according to claim 1, wherein the flexible region is guided out of the rigid region via a feedthrough, the feedthrough having a width less than a width of the rigid region.

7. The autoclavable electronics unit according to claim 1, wherein the flexible region comprises one or more nominal bending points having a thickness less than a thickness of other portions of the flexible region.

8. The autoclavable electronics unit according to claim 1, wherein the flexible region of the printed circuit board comprises one or more soldered contact points, each connected to one of a cable and another printed circuit board.

9. The autoclavable electronics unit according to claim 1, wherein the flexible region is covered by a seal formed of a silicone material, the seal sealingly adjoining the epoxy resin.

10. The autoclavable electronics unit according to claim 1, wherein the silicone material is at least partially transparent.

11. The autoclavable electronics unit according to claim 1, wherein the flexible region is guided out of the rigid region via a feedthrough, the seal further covering the feedthrough.

12. The autoclavable electronics unit according to claim 1, wherein the flexible region is provided with one or more LEDs for signal transmission.

13. The autoclavable electronics unit according to claim 1, wherein the flexible region is provided with an electrical contact point for a digital interface.

14. The autoclavable electronics unit according to claim 1, wherein at least part of the conductor tracks are enclosed with shielding structures.

15. The autoclavable electronics unit according to claim 1, wherein the shielding structures comprise one or more of protective rings or U-shaped structures.

16. A method for producing an autoclavable electronics unit for an endoscope, the method comprising: a) producing a flexible multi-layer printed circuit board from structured layers of conductive and non-conductive materials adhered together, in which the conductive structures form conductor tracks and contact surfaces, b) producing a rigid region of the flexible printed circuit board by reinforcing the rigid region with one of an additional stiffening plate or one or more stiffening layers, wherein a flexible region of the flexible printed circuit board is not reinforced with the one of the additional stiffening plate or the one or more stiffening layers. c) providing the rigid region of the printed circuit board with one or more electronic components, d) covering the rigid region with an epoxy resin.

17. The method according to claim 16, wherein the covering comprises filling the epoxy resin with ceramic powder.

18. The method according to claim 16, wherein the covering comprises one of injecting or casting the epoxy resin to surround the rigid region.

19. The method according to claim 16, further comprising connecting a flexible region of the printed circuit board to another printed circuit board via soldered contact points.

20. The method according to claim 16, further comprising sealing the flexible region of the printed circuit board with a silicone material, wherein the silicone material sealingly adjoins the epoxy resin of the rigid region.

21. The method according to claim 16, further comprising checking the printed circuit board and the at least one electronic component for proper functioning via one or more optical or electronic interfaces provided in the flexible region of the printed circuit board.

22. An endoscope comprising the autoclavable electronics unit according to claim 1 in a non-hermetic portion of the endoscope.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Further features will become evident from the description of embodiments, together with the claims and the appended drawings. Embodiments can fulfil individual features or a combination of multiple features.

[0029] The embodiments are described below, without restricting the general idea of the invention, based on exemplary embodiments in reference to the drawings, whereby we expressly refer to the drawings with regard to the disclosure of all details that are not explained in greater detail in the text. In the figures:

[0030] FIG. 1 illustrates a schematic sectional representation of an autoclavable electronics unit and

[0031] FIG. 2 illustrates a schematic representation of a top view of an autoclavable electronics unit.

[0032] In the drawings, the same or similar elements and/or parts are, in each case, provided with the same reference numerals such that they are not introduced again in each case.

DETAILED DESCRIPTION

[0033] FIG. 1 is a schematic sectional representation of an autoclavable electronics unit 10. It is based on a multi-layer printed circuit board 20, the layers of which are represented as white and black layers. These different layers are connected to one another by means of an adhesive. The conductive structures form conductor tracks within the different layers. In some areas, the conductive structures are contacted through (not shown) between the layers so that a three-dimensional conductor track structure is formed. The printed circuit board 20 is in principle configured to be flexible, i. e., it can be rolled or bent, respectively.

[0034] In order to receive electronic components 34, a part of the printed circuit board 20 is reinforced by means of a stiffener 32 and thereby forms a rigid region 30. A further region of the printed circuit board 20 is not reinforced and thereby forms a flexible region 50. The flexible region 50 is not equipped with electronic components 34.

[0035] For sealing, at least the rigid region 30, such as an entirety of the rigid region 30, is coated with an epoxy resin covering 36 on one or both of the bottom side and the top side. For the application of the epoxy resin covering 36, an injection method was used which ensures that a homogeneous layer thickness of the epoxy resin covering 36 is achieved. To match the thermal and mechanical properties of the electronic components 34, it is useful to use a filled epoxy resin for the coating, which is filled with a ceramic powder that provides the epoxy resin with thermal and mechanical properties that are similar to those of the electronic components 34, so that stress cracking of the coating and lifting of the coating from the printed circuit board 20 do not occur even with repeated autoclaving under high temperatures.

[0036] In the flexible region 50, the thickness of the printed circuit board 20 is reduced compared to the thickness in the rigid region 30. This is apparent from the reduced number of layers in the multi-layer printed circuit board 20 compared to the number of layers in the rigid region 30. This further increases the flexibility of the flexible region 50 compared to the rigid region 30. In the flexible region 50, there are nominal bending points 66 on the bottom side of the printed circuit board 20, which are generated by reducing the layer thickness of a non-conductive material of the printed circuit board 20, and which represent especially flexible regions of the printed circuit board 20.

[0037] On the top side of the printed circuit board 20, an SMD (surface mounted device) LED 62 as well as a soldered contact point 56 are arranged in the flexible region 50. The top side of the printed circuit board 20 is provided with a silicone seal 64 in the flexible region 50. Such silicone seal is transparent, partially or in its entirety, such that optical signals from the LED can be viewed from the outside. The silicone seal 64 adjoins flush to the epoxy resin covering 36 or overlaps it partially. The bottom side of the printed circuit board 20 is not necessarily sealed with a silicone layer in the flexible region 50, since this side does not have any electrically conductive surfaces or electronic components to be protected.

[0038] FIG. 2 shows a schematic representation of a top view of an autoclavable electronics unit, which can correspond with the one from FIG. 1. The rigid region 30 is shown completely covered. A tapered feedthrough 40 is arranged between the printed circuit board 20 coated in the rigid region 30 and the not rigidly coated part of the printed circuit board 20 in the flexible region 50. The taper of the feedthrough 40 serves to reduce the contact surface for moisture during autoclaving so that the least possible amount of damaging moisture or other substances can enter through the feedthrough 40 into the intermediate space between the epoxy resin covering 36 and the printed circuit board 20.

[0039] In the flexible region 50 of the printed circuit board 20, the structures arranged on the top side of the printed circuit board 20 are apparent. Here, these are several soldered contact points 52, 56, LEDs 62, bare-metal surfaces 58, as well as a contact surface 60 for a serial interface.

[0040] The soldered contact points 52, of which there is a total of four in the example shown, serve to connect to a further printed circuit board. During bending of the flexible part and insertion in the non-hermetic part of an endoscope, such soldered points are exposed to high mechanical stresses. In order for these stresses not to result in the rupture of the soldered contacts, the soldered contact points 52 are each arranged at the ends of flexible arms 55, which are formed by shaping a recess 54 in the printed circuit board 20. Since the arms 55 are configured to be spring-loaded, the mechanical stress on the connecting soldered points themselves is reduced far enough for the connections to be robust. Further soldered contact points 56 serve to establish the connection with electrical cables the open ends of which are soldered to these points.

[0041] With the LEDs 62, as well as with the serial interface 60, signals from the electronics unit mounted in the rigid part 30 can be received, and in the case of the serial interface 60, can also be sent, which allow for diagnosing the electronics unit as well as the status of the conductor tracks of the printed circuit board 20.

[0042] The bare-metal surfaces 58 are used for identification and can, for example by means of a laser writing method, be labeled with a type number, serial number, or similar information.

[0043] A sealing of the flexible region 50 as well as of the feedthrough 40 with a silicone layer is implemented equally after completing the contacting of the soldered contact points 52, 56 to further printed circuit boards and/or electrical conductors.

[0044] The thus represented electronics unit 10 is protected against the influences of moisture, hot vapor, or other aggressive cleaning substances during autoclaving.

[0045] While there has been shown and described what is considered to be preferred embodiments, it will, of course, be understood that various modifications and changes in form or detail could readily be made without departing from the spirit of the invention. It is therefore intended that the invention be not limited to the exact forms described and illustrated, but should be constructed to cover all modifications that may fall within the scope of the appended claims.

LIST OF REFERENCE SIGNS

[0046] 10 Autoclavable electronics unit [0047] 20 Multi-layer printed circuit board [0048] 30 Rigid region [0049] 32 Stiffener [0050] 34 Electronic components [0051] 36 Epoxy resin covering [0052] 40 Feedthrough [0053] 50 Flexible region [0054] 52 Soldered contact point [0055] 54 Recess [0056] 55 Flexible arm [0057] 56 Soldered contact point [0058] 58 Bare-metal surfaces [0059] 60 Contact surface for serial interface [0060] 62 SMD LEDs [0061] 64 Silicone seal [0062] 66 Nominal bending point