TEMPERATURE SENSOR AND METHOD FOR PRODUCING A TEMPERATURE SENSOR

Abstract

A method (100) for producing a temperature sensor (200), the method (100) comprising: providing (101) a cable (103), wherein electrical conductor portions (105) are protruding from an end of the cable (103); connecting (107) at least one temperature sensor element (109) to the electrical conductor portions (105) protruding from the cable (103); providing (111) a sensor capsule (113); connecting (115) a proximal end surface of the sensor capsule (113) to the end of the cable (103), so that the sensor capsule (113) surrounds the at least one temperature sensor element (109); providing (117) at least one drain opening (119) in the sensor capsule (113) near a connection area (121) of the cable (103) and the sensor capsule (113); filling (123) up a volume (125) of the sensor capsule (113) with a thermally conducting ceramic filler (127); connecting (129) an end cap (131) to a distal end surface (133) of the sensor capsule (113); sealing (135) the drain opening (119).

Claims

1. A method for producing a temperature sensor, the method comprising: providing a cable, wherein conducting electrical conductor portions are protruding from an end of the cable, connecting at least one temperature sensor element to the electrical conductor portions protruding from the cable, providing a sensor capsule, connecting a proximal end surface of the sensor capsule to the end of the cable, so that the sensor capsule surrounds the at least one temperature sensor element, providing at least one drain opening in the sensor capsule near a connection area of the cable and the sensor capsule, filling up a volume of the sensor capsule with a thermally conducting ceramic filler, connecting an end cap to a distal end surface of the sensor capsule, sealing the drain opening.

2. The method according to claim 1, the method further comprising: curing the ceramic filler before the end cap is connected to the distal end surface of the sensor capsule.

3. The method according to claim 1, wherein the at least one temperature sensor element is welded, in particular laser welded, to the electrical conductor portions protruding from the cable.

4. The method according to claim 1, wherein connecting the at least one temperature sensor element to the electrical conductor portions protruding from the cable comprises connecting two different electrical conductors.

5. The method according to claim 1, wherein the thermally conducting ceramic filler is a ceramic cement potting material.

6. The method according to claim 1, wherein the proximal end surface of the sensor capsule is welded to the end of the cable.

7. The method according to claim 1, wherein the end cap is welded to the distal end surface of the sensor capsule.

8. The method according to claim 1, wherein the cable is a mineral insulated cable.

9. The method according to claim 1, wherein the at least one temperature sensor element comprises platinum wires.

10. The method according to claim 1, wherein providing at least one drain opening in the sensor capsule comprises: drilling at least one hole in a wall of the sensor capsule, or forming a recess in the distal end of the sensor capsule, or forming a circumferentially incomplete welding seam in a first welding operation, when connecting to the cable, so that a small gap section is formed in an interface between the end of the cable and the proximal end of the sensor capsule, and sealing the drain opening in a second welding operation after filling up the sensor capsule volume with the ceramic filler.

11. A temperature sensor produced by the method according to claim 1.

12. The method according to claim 2, wherein the at least one temperature sensor element is welded, in particular laser welded, to the electrical conductor portions protruding from the cable.

13. The method according to claim 2, wherein connecting the at least one temperature sensor element to the electrical conductor portions protruding from the cable comprises connecting two different electrical conductors.

14. The method according to claim 3, wherein connecting the at least one temperature sensor element to the electrical conductor portions protruding from the cable comprises connecting two different electrical conductors.

15. The method according to claim 2, wherein the thermally conducting ceramic filler is a ceramic cement potting material.

16. The method according to claim 3, wherein the thermally conducting ceramic filler is a ceramic cement potting material.

17. The method according to claim 4, wherein the thermally conducting ceramic filler is a ceramic cement potting material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Hereinafter, preferred embodiments of the present disclosure will be described with reference to the accompanying drawings. In the drawings:

[0031] FIG. 1 shows an embodiment of a method for producing a temperature sensor according to the present invention.

DETAILED DESCRIPTION

[0032] First, it should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present disclosure, and are not intended to limit the scope of protection of the present disclosure. For example, although the following embodiments are explained in conjunction with an apparatus, this is not limitative. The technical solutions of the present disclosure are also applicable to other devices. Such a change to application object does not deviate from the principle and scope of the present disclosure.

[0033] In addition, it should also be noted that in the description of the present disclosure, unless otherwise clearly specified and defined, terms “dispose”, “install”, “connect” and “connection” should be understood in a broad sense; for example, the connection may be a fixed connection, or may also be a detachable connection, or an integral connection; it may be a mechanical connection, or an electrical connection; it may be a direct connection, or an indirect connection implemented through an intermediate medium, or it may be an internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in the present disclosure can be understood according to specific situations.

[0034] In FIG. 1, a method 100 for producing a temperature sensor 200 is shown.

[0035] The method 100 comprises a first provisioning step 101, in which a cable 103, such as a MI cable comprising an outer metal sheath filled with mineral material 103b for example, is provided, wherein electrical conductor portions 105 are protruding from an end of the cable.

[0036] Further, the method 100 comprises a connection step 107, in which at least one temperature sensor element 109 is connected to the electrical conductor portions 105 protruding from the cable 103. According to an example, the connection step may comprise connecting two different electrical conductors, such as Ni and NiCr conductors, in a welding joint to form a thermocouple. In particular, platinum wires 109a may be used as connection elements connections the at least one temperature sensor element 109 to the electrical conductor portions 105.

[0037] Further, the method 100 comprises a second provisioning step 111, in which a metal sensor capsule 113 is provided. The sensor capsule 113 is connected with its proximal end surface to the end of the cable 103, preferably to the end surface of the metal sheath 103a, so that the sensor capsule 113 surrounds the at least one temperature sensor element 109, in a first connection step 115.

[0038] Further, the method 100 comprises a third provisioning step 117, in which at least one drain opening 119 is provided in the sensor capsule 113 near a connection area 121 of the cable 103 and the sensor capsule 113. According to an example, the connection area 121 is located between the sensor capsule 113 and the metal sheath 103a of the cable 103, such that the drain opening 119 forms a small gap between the sensor capsule 113 and the cable 103, which is sealed after filling step 123 by a welding process, for example. Alternatively, the drain opening 119 may be formed in the sensor capsule 113 before the sensor capsule 113 is connected to the cable 103, such that the sensor capsule 113 can be pre-fabricated including the drain opening 119. In this case, the drain opening 119 may be formed as a hole in the wall or as a recess in a proximal end surface of the of the sensor capsule 113.

[0039] Further, the method 100 comprises filling and curing step 123, in which a volume 125 of the sensor capsule 113 is filled with a thermally conducting ceramic filler 127 and subsequently cured in a curing process with a predetermined temperature profile, for example.

[0040] Further, the method 100 comprises a second connection step 129, in which an end cap 131 is connected to a distal end surface 133 of the sensor capsule 113.

[0041] Further, the method 100 comprises a sealing step 135, in which the drain opening 119 is sealed by a sealing 137. The sealing 137 may comprise a separate sealing element pressed and/or welded into the drain opening, or may comprise melted sensor capsule or cable sheath material.