Method and device for controlling the switching movement of a valve

• US 20040211928A1
• Filed: 06/09/2004
• Published: 10/28/2004
• Est. Priority Date: 05/12/2001
• Status: Active Grant

• Current Assignee: Tuchenhagen GmbH (GEA Group AG)
• Original Assignee: Tuchenhagen GmbH (GEA Group AG)
• Inventors: Gesikiewicz, Martin, Coura, Herbert, Porath, Bernd
• Granted Patent: US 7,032,878 B2
• Time in Patent Office: Days
• US Class Current: 251/129.04
• CPC Class Codes: F16K 1/446 with additional cleaning or venting means between the two seats
• CPC Class Codes: F16K 31/003 operated without a stable intermediate position, e.g. with snap action F16K31/56 takes precedence
• CPC Class Codes: F16K 31/1225 with a plurality of pistons
• CPC Class Codes: F16K 37/0033 using a permanent magnet, e.g. in combination with a reed relays
• CPC Class Codes: F16K 37/0083 by measuring valve parameters
• CPC Class Codes: Y10T 137/8242 Electrical
• CPC Class Codes: Y10T 137/8275 Indicator element rigidly carried by the movable element whose position is indicated
• CPC Class Codes: Y10T 137/88038 One valve head carries other valve head

Abstract

The invention relates to a method for controlling the switching movement of a valve, by means of which the device carries out the above in a simpler fashion than with conventional devices, manipulation advantages are achieved and the recognition of defined, fixed valve positions is more certain. The above is achieved in a method whereby both end positions and the intermediate position(s) of the valve are clearly fixed by indirect or direct arrangement or the valve rod(s) at fixed positions (A1, A2, A3, A4), whereby, during the first switching movement of the valve, the fixed positions (A1, A2 . . . ) are each arrived at and the resulting fixed positional signal (y₁, y₂, y₃, y₄) is stored, a given tolerance range (ΔT_1i; ΔT_2i; Δt_3i; ΔT_4i) is assigned to each value (y₁, y₂ . . . ) and both threshold values (y_1o, y_1u; y_2o, y_2u; y_3o, y_3u; y_4o, y_4u) for the given tolerance range (ΔT_1i, ΔT_2i, . . . ) are calculated. During the subsequent switching movement of the valve, a fixed position signal (y₁*, y₂*, y₃*, y₄*) for one of the current end positions and/or the current intermediate position(s) are taken and compared with the both threshold values (y_1o, y_1u; y_2o, y_2u; . . . ) for the relevant tolerance range (ΔT_1i, ΔT_2i . . . ). Where the current fixed positional signal (y₁*, Y₂*, y₃*, y₄*) approaches the corresponding threshold value (y_1o, y_1u; y_2o, y_2u; . . . ) and/or on leaving the corresponding tolerance range (ΔT_1i, ΔT_2i, . . . ) a switching and/or status signal is generated.

Claims

1. A method for the control of the switching operation of a valve which has at least one valve rod which is translationally moved and carries a closing member wherein the valve rod(s), by means of a drive to which a pressure medium is applied, is/are moved to two end positions resulting in a full stroke (H) wherein at least one valve rod is moved, if required, to an intermediate position located between said end positions and forming a partially opened position of the closing member, wherein the actual position of the valve rod illustrating the movement of the valve rod is continuously detected via a position detector in relation to a fixed reference system and the relevant position messages (y) are continuously stored, and a comparison is provided between this actually gained data and that which was stored prior to the first switching operation of the valve

characterized in

that the two end positions and the intermediate position(s) are clearly determined by the valve rod(s) bearing directly or indirectly on fixed position limiters (A1, A2, A3, A4),

that the fixed position limiters (A1, A2 . . . ) each are moved to in the course of the first switching operations of the valve and the respective resultant fixed position messages (y₁, y₂, y₃, y₄) are stored,

that the fixed position messages (y₁, y₂ . . . ) have associated therewith a predetermined tolerance range each (Δ

T_1i, Δ

T_2i, Δ

T_3i, Δ

T_4i) and the two limiting values (y_1o, y_1u;

y_2o, Y_2u;

Y_3o, y_3u;

y_4o, y_4u) of the respective tolerance range (Δ

T_1i, Δ

T_2i, . . . ) are calculated therefrom,

that an actual fixed position message (y₁*, y₂*, y₃*, y₄*) associated with each of the actual end positions and/or the actual intermediate position(s) is/are resorted to during the subsequent switching operations of the valve and is/are compared to the two limiting values (y_1o, y_1u;

y_2o, y_2u;

. . . ) of the tolerance range concerned (Δ

T_1i, Δ

T_2i, . . . ),

and that a switching signal and/or message signal is/are generated when the actual fixed position messages values (y₁*, y₂*, y₃*, y₄*) approach the associated limiting values (Y_1o, y_1u;

y_2o, y_2u;

. . . ) and/or when the associated tolerance range (Δ

T_1i, Δ

T_2i, . . . ) is exited.

2. The method according to claim 1, characterized in that the data stored before the first switching operation of the valve are withdrawn from a record (DS) deposited in the control which identifies and monitors the respective configuration of the valve, its switching motions, and its switching algorithm.

3. The method according to claim 2, characterized in that tolerance ranges (Δ

T_1i, Δ

T_2i, Δ

T_3i, Δ

T_4i)) of different quality levels (i=1, 2, 3, . . . ) are contained in the data record (D) wherein each quality level (i) comprises a tolerance range set (Δ

T₁₁, Δ

T₂₁, (Δ

T₃₁, Δ

T₄₁;

Δ

T₁₂, Δ

T₂₂, (Δ

T₃₂, Δ

T₄₂;

Δ

T₁₃, Δ

T₂₃, . . . Δ

T₁₄, Δ

T₂₄;

. . . ).

4. The method according to claim 3, characterized in that the fixed position messages (y₁, y₂, y₃, y₃) have associated therewith a tolerance range set.

5. The method according to claim 3, characterized in that the fixed position messages (y₁, y₂, y₃, y₃), respectively, have associated therewith tolerance ranges of different quality levels (i).

6. The method according to claim any one of claim 1, characterized in that the tolerance range (Δ

T_1i, Δ

T_2i, Δ

T_3i, Δ

T_4i) is arranged in asymmetry with and in favour of a most likely alteration of the associated fixed position message (y₁, y₂, y₃, y₃) to the latter (y_1o=y₁+φ

Δ

T_1i, y_1u=y₁₋

[1−

φ

]Δ

T_1i with a fraction factor φ

where 0≦

φ

≦

1;

. . . ).

7. The method according to claim any one of claim 1, characterized in that the tolerance range (Δ

T_1i, Δ

T_2i, Δ

T_3i, Δ

T_4i) is arranged in symmetry with the associated fixed position message (y₁, y₂, y₃, y₄)(y_1o=y₁+Δ

T_1i/2;

y_1u=y₁−

Δ

T_1i/2;

. . . , where φ

is 0.5).

8. The method according to claim any one of claim 1, characterized in that when an approximation of the actual fixed position messages (y₂*, Y₂*, y₃* y₄* to the associated limiting values (Y_1o, y_1u, y_2o, y_2u;

. . . ) of the tolerance range (Δ

T_1i, Δ

T_2i, Δ

T_3i, Δ

T_4i) is effected a maintenance signal is generated where said approximation is defined by an approximation tolerance Δ

_tw each which joins the respective limiting values ((y_1o, y_1u, y_2o, y_2u;

. . . ).

9. A device for the implementation of the method according to claim 1, comprising

a valve (100) having at least one valve rod (101;

102) which is translationally moved and carries a closing member (101;

102),

a valve drive (105), to which a pressure medium is applied, for the valve rod(s) (3, 101a;

102a),

means for controlling the pressure medium for the valve drive (105),

a position detector (5) which is connected to the valve rod (3, 101a) and continuously detects the actual position of the valve rod (3, 101a) that illustrates the valve rod movement in relation to a fixed reference system and provides relevant actual position messages (y),

means for the continuous storage of said actual position messages (y), and

means for the calculation and comparison between data from data predetermined prior to the first switching operation of the valve and/or in the course of the valve operations,

characterized in

that two end positions (y₁, y₂) of the valve rod (3, 101a) which result in a full stroke (H) are clearly determined by the valve rod bearing directly or indirectly on fixed position limiters (A1, A2),

that an intermediate position (y₃, y₄) each of the valve rod (3, 101a;

102a) between the end positions (y₁, y₂) are clearly determined by the valve rod(s) bearing directly or indirectly on fixed position limiters (A3, A4) to define a partially opened position of the respective closing member (102, 102),

that the position detector (5) is formed as a non-contacting position indicator which operates in a non-contacting way and which, in a sensor unit (5.1), has a number of stationary magnetic-field converters (5.1a) in a series array in parallel with and in the vicinity of a valve rod movement to be detected, and a magnet (4) which is connected to the valve rod (3) is displaceable along the magnetic-field converters (5.1a)

and that all of the means required for the control of the valve (100) are arranged in a control head (1) which is provided on the side of the valve drive (105) which faces away from the valve (100).

10. The device according to claim 9, characterized in that the position detector (5), in a sensor unit (5.1), has a number of stationary magnetic-field converters (5.1a) which are arranged in a series array in parallel with and in the vicinity of a valve rod movement to be detected, and that a magnet (4) which is connected to the valve rod (3) is displaceable along the magnetic-field converters (5.1a).

11. The device according to claim 9, characterized in that the fixed position limiters (A1, A2, A3, A4) are formed as metallic stops.

12. The device according to claim 9, characterized in that the control head (1) has provided therein an installation block (2) which receives the entire distribution system for the pressure medium in itself and carries the pilot valves (9, 10, 11, 15) for the control of the pressure medium and the position detector (5) comprising the sensor unit (5.1) and a communication unit (5.2).

13. The device according to claim 11, characterized in that the installation block (2) is designed for the highest completion stage of the control of a valve (100) (the control of the two end positions and the intermediate positions each of the valve disk and double disk) and that completion is performed in a modular way.

14. The device according to claim 9, characterized in that the pressure medium which triggers the valve drive (105) for the generation of the full stroke (H) is fed via a valve rod bore (3b) in the valve rod (3).

15. The device according to claim 9, characterized in that the pressure medium for triggering the valve drive (105) for the generation of the full stroke (H) is fed to the valve drive (105) from outside via a first pressure medium connection (106a).

16. The device according to claim 9, characterized in that the valve drive (105) has a fourth pressure medium connection (106d) via which, when the valve (100) is in the closed position, the closing force onto the valve rod (3, 101a) is increased by a supply of pressure medium.

17. The device according to claim 9, characterized in that the position detector (5) is equipped with more than one indicator lamp (12) of different colorations, the indicator lamp (12) being visible all around (through 360°

) via a stray light lens (21a) which is disposed in the closed front-end face of a covering hood (21) locking the control head (21).