Pressure measurement cell

• US 20020026836A1
• Filed: 05/25/2001
• Published: 03/07/2002
• Est. Priority Date: 09/01/2000
• Status: Abandoned Application

• Current Assignee: Endress+Hauser GmbH+Co (ENDRESS)
• Original Assignee: Endress+Hauser GmbH+Co (ENDRESS)
• Inventors: Hegner, Frank, Drewes, Ulfert
• Application Number:
  US09/864,173
• Publication Number:
  US 20020026836A1
• Time in Patent Office: Days
• US Class Current: 73/717
• CPC Class Codes: G01L 9/0075 using a ceramic diaphragm, e.g. alumina, fused quartz, glass

Abstract

A pressure measurement cell is provided whose measurement accuracy is stable over a long time, having a first and a second base body (1, 3), and arranged between the first and the second base body (1, 3), at a distance from them, a measurement membrane (5) which has a low-pressure side on which it is connected to the first base body (1), at a first outer edge, to form a first chamber (7), and which has a high-pressure side on which it is connected to the second base body (3), at a second outer edge, to form a second chamber (9), the first edge being wider than the second edge.

Claims

1. A pressure measurement cell, having

a first and a second base body (1, 3),

and arranged between the first and the second base body (1, 3), at a distance from them, a measurement membrane (5)

which has a low-pressure side on which it is connected to the first base body (1), at a first outer edge, to form a first chamber (7), and

which has a high-pressure side on which it is connected to the second base body (3), at a second outer edge, to form a second chamber (9),

the first edge being wider than the second edge.

2. The pressure measurement cell as claimed in claim 1, in which the measurement membrane (5) consists of ceramic, and it is connected to the first base body (1) by means of a first joint (11) and is connected to the second base body (3) by means of a second joint (13).

3. The pressure measurement cell as claimed in claim 1, in which the first chamber (7) is evacuated.

4. The pressure measurement cell as claimed in claim 1, in which a reference pressure (p_R) , delivered through an opening (35) in the first base body (1), prevails in the first chamber (7).

5. The pressure measurement cell as claimed in claim 3 or 4, in which a pressure corresponding to a pressure (p) to be measured, delivered through an opening (15) in the second base body (3), prevails during operation in a second chamber (9) delimited by the second base body (3) and the measurement membrane (5).

6. The pressure measurement cell as claimed in claim 5, in which the second chamber (9) is connected to a pressure transmitter (17), via which a pressure corresponding to a pressure (p) to be measured is transmitted to the second chamber (9) during operation.

7. The pressure measurement cell as claimed in claim 1, in which

a pressure corresponding to a first pressure (p⁻

), delivered through an opening (37) in the first base body (1), prevails in the first chamber (7) during operation, and

a pressure corresponding to a second pressure (p⁺), delivered through an opening (39) in the second base body (3), prevails in the second chamber (9) during operation.

8. The pressure measurement cell as claimed in claim 7, in which

the first chamber (7) is connected to a pressure transmitter (43), via which a pressure corresponding to the first pressure (p⁻

) is transmitted to the first chamber (7) during operation, and

the second chamber (9) is connected to a pressure transmitter (47), via which a pressure corresponding to the second pressure (p⁺) is transmitted to the second chamber (9) during operation.