USE OF A MULTI-START SCREW THREAD IN AN EX-D HOUSING

Abstract

The invention relates to a field device of automation technology, including a housing with an opening for accommodating field device components, wherein the housing has at an edge of the opening a first screw thread, a lid for closing the opening of the housing, wherein the lid has at an edge of the lid a second screw thread, wherein the first and second screw threads are embodied to be complementary to one another, so that the housing after closing by means of the lid fulfills all Ex-d requirements, wherein the first and second screw threads are embodied as multi-start screw threads.

Claims

1-4. (canceled)

5. A field device of automation technology, comprising a housing with an opening for accommodating field device components, wherein the housing has at an edge of the opening a first screw thread; and a lid for enclosing the opening of the housing, wherein the lid has at an edge of the lid a second screw thread, wherein the first screw thread and the second screw thread are embodied to be complementary to one another, such that the housing after enclosing with the lid fulfills all Ex-d requirements, and wherein the first screw thread and the second screw thread are embodied as multi-start screw threads.

6. The field device of claim 5, wherein the first screw thread and the second screw thread are embodied as four-start screw threads.

7. The field device of claim 5, wherein the first screw thread and the second screw thread have axially at least five starts.

8. The field device of claim 5, wherein the first screw thread and the second screw thread have axially eight starts.

9. A lid-closing mechanism of a field device of automation technology, comprising a housing embodied to fulfill all Ex-d requirements, the housing including lid-closing mechanism having a multi-start thread.

Description

[0011] The invention will now be explained in greater detail based on the appended drawing, the figures of which show as follows:

[0012] FIG. 1 a longitudinal section of a housing of a field device of automation technology according to the state of the art, and

[0013] FIG. 2 a front view of a lid of the invention with four screw threads extending in parallel to form a four-start screw thread for a housing with a four-start screw thread.

[0014] FIG. 1 shows a longitudinal section of a housing 1 of a field device 1 of automation technology according to the state of the art. Housing 1 includes a housing 2 and a lid 6. The housing 2 and the lid 6 are pot shaped. The housing 2 is fashioned to accommodate field device components 4 and includes, for this purpose, an opening 3. The housing 2 includes in an outer edge region at the opening 3 a first screw thread 5. The lid 6 includes in an outer edge region a second screw thread 7.

[0015] The first and second screw threads 5, 7 are complementary to one another. If the housing 2 is closed by means of the lid 6, housing 1 fulfills all Ex-d requirements.

[0016] FIG. 2 shows a front view of a lid 6 of the invention for a housing 2 with a four-start screw thread. The second screw thread 7 of the lid 6 is embodied as a four-start screw thread. Lid 6 has in another embodiment a second screw thread 7 with eight starts.

LIST OF REFERENCE CHARACTERS

[0017] 1 housing of a field device of automation technology

[0018] 2 housing

[0019] 3 opening

[0020] 4 field device components

[0021] 5 first screw thread

[0022] 6 lid

[0023] 7 second screw thread