Optoelectronic sensor and method for focus adjustment

Patent metadata

Field	Value
Publication number	US-12010424-B2
Application number	US-202318202113-A
Country	US
Kind code	B2
Filing date	May 25, 2023
Priority date	Jun 24, 2022
Publication date	Jun 11, 2024
Grant date	Jun 11, 2024

Abstract

An optoelectronic sensor comprising a light receiver, receiving optics in front of the light receiver, and a focus adjustment unit having an actuator and configured to move the light receiver, wherein the focus adjustment unit comprises a parallel guide having at least one flexible retaining element and moving the light receiver in a constant orientation on the optical axis of the receiving optics.

First claim

The invention claimed is:

1. An optoelectronic sensor comprising:
a light receiver;
receiving optics in front of the light receiver; and
a focus adjustment unit having an actuator and configured to move the light receiver, wherein the focus adjustment unit comprises a parallel guide having at least one flexible retaining element and moving the light receiver in a constant orientation on an optical axis of the receiving optics,
wherein the at least one flexible retaining element comprises a thermally-conductive layer, and
wherein the at least one flexible retaining element further comprises two metal layers, the thermally-conductive layer being positioned therebetween.

2. The sensor according to claim 1 ,
wherein the actuator comprises a stepper motor or a moving coil.

3. The sensor according to claim 1 ,
wherein the sensor comprises a position sensor for determining the position of the actuator, the parallel guide, or the light receiver.

4. The sensor according to claim 1 ,
wherein the light receiver is arranged on a printed circuit board comprising at least one flexible section.

5. The sensor according to claim 4 ,
wherein the printed circuit board comprises rolled copper at least in the flexible section.

6. The sensor according to claim 1 ,
wherein the parallel guide comprises a fixed first bearing and an opposite, movable second bearing, and wherein the flexible retaining element is mounted with a first side in the first bearing and with an opposite second side in the second bearing.

7. The sensor according to claim 6 ,
wherein the light receiver is at least indirectly rigidly connected to the second bearing and flexibly or not at all connected to the first bearing.

8. The sensor according to claim 1 ,
wherein the at least one flexible retaining element is configured as a frame around the light receiver.

9. The sensor according to claim 1 ,
wherein the at least one flexible retaining element comprises at least one leaf spring.

10. The sensor according to claim 1 ,
wherein the parallel guide comprises two flexible retaining elements, and wherein the light receiver is arranged between the two flexible retaining elements.

11. The sensor according to claim 1 ,
wherein the at least one flexible retaining element comprises a thermally-conductive metal.

12. The sensor according to claim 11 ,
wherein the thermally-conductive metal comprises copper or a copper-beryllium alloy.

13. The sensor according to claim 1 ,
wherein the at least one flexible retaining element comprises at least one rigid region in which the material is thickened.

14. The sensor according to claim 13 ,
wherein the material is thickened by means of at least one additional metal strip.

15. The sensor according to claim 1 ,
wherein the thermally-conductive layer comprises a graphite foil.

16. The sensor according to claim 1 ,
comprising a control and evaluation unit configured to read out code information of a code recorded in image data acquired with the light receiver.

17. A method for adjusting the focus of an optoelectronic sensor comprising a light receiver and receiving optics arranged in front of the light receiver, the method comprising:
moving the light receiver by means of a focus adjustment unit using an actuator, wherein the focus adjustment unit moves the light receiver in constant orientation on an optical axis of the receiving optics by means of a parallel guide having at least one flexible retaining element,
wherein the at least one flexible retaining element comprises a thermally-conductive layer, and
wherein the at least one flexible retaining element further comprises two metal layers, the thermally-conductive layer being positioned therebetween.

18. The method according to claim 17 ,
wherein the thermally-conductive layer comprises a graphite foil.

Assignees

• Sick Ag

Inventors

• Pfrengle Thomas
• Burger Jakob

Classifications

• H02K41/0354

  Lorentz force motors, e.g. voice coil motors · CPC title

• H02K37/00

  Motors with rotor rotating step by step and without interrupter or commutator driven by the rotor, e.g. stepping motors · CPC title

• G06K7/1413

  1D bar codes · CPC title

• G01D5/142

  using Hall-effect devices (measuring magnetic variables using Hall-effect or other galvanomagnetic devices G01R33/06) · CPC title

• H04N23/67 Primary

  Focus control based on electronic image sensor signals · CPC title