DE2119494A1 - Device for displaying the operating position of a valve - Google Patents

Description

April 19, 1971

JAMES SCOTT (SLECTROMIC ENGINEERING) LIMITED , Carrityne Industrial Estate, Glasgow, E. 2., Scotland

Device for displaying the operating position of a valve,

The invention relates to a device for display the operating position of a valve, which can be used in particular for diagrams of pipeline systems and the like, it should be clearly visible whether the associated valve is in the open or closed position or in a Intermediate position is.

For this purpose, a device for "displaying the Operating position of a valve by means of a resistance transmitter according to the invention as a function of each position of the Resistance value of the resistance sensor assigned to each valve a motor is switched on with the corresponding direction of rotation, whichever causes the setting of the display device.

It is useful if the display device is preferred colored bar, which is attached to the output shaft of the motor. Here it is beneficial to use the Koppelelernence to choose between motor and display device so that when changing between open and closed Operating position of the valve, the bar is rotated by 90.

It is advantageous if the resistance transmitter is used as a variable resistance, preferably as a rotary resistance, is executed.

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In a preferred embodiment, it is used as a display device serving bars in a the Rohrleitungεsys system schematically depicting Scliaubild. assigned to the cern Valve corresponding. Location of the pipeline concerned arranged ..

In the following , the invention is described in connection with the figures depicting embodiments; In this case, all details not required for understanding the invention have been omitted , and the illustration is partially simplified schematically. Corresponding parts are identified in the figures in the same way.

,It shows:

Fig, l. The application of display device according to the invention ^ connections in a diagram for pipelines,

Fig. 2 as an exploded view with partially removed housing, a display device in connection with a servo motor,

3 shows a switch cabinet for the servo motor,

4 shows the arrangement of the display device in one Pipeline system.

Fig. 1 shows a system of pipelines 1 and display devices 2, 3, 4 for three valves. The display device belongs to a fully open valve, the display device ί · device 3 to a fully closed valve and the display device 4 to a valve in a half-open Position. ■

From Pig. 2 it can be seen that each display device has a colored bar 5, which is attached to the shaft 6, which is driven by a remote-controlled motor 7.

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BATH ORIGINAL

The beam 5 is between a glass plate 8 and a Dial 9 arranged, which are held by means of a spacer ring 10 in a housing 11 at a suitable distance.

The motor 7 assembled with a thread is fixed in a housing 12 and carried by a support body 13, which also carries an annular resistance element 14. The shaft 6 carries a sliding contact 15 on the Resistance element 14 grinds and a pin 16 which cooperates with rubber bodies 17, which are part of the clamping device 18 form, which hold the resistance element 14 in the intended position.

The arrangement here is through a corresponding transmission ratio selected in the transmission so that when the valve is moved from the closed to the open state the bar 5 is rotated by SO. A further movement of the bar by 10 is possible in both directions, This eliminates errors, especially those in the resistance element 14, to display.

A printed circuit board 19 containing the amplifier and the other electrical components for the remote control or the servo system of the motor is inside the Housing 12 arranged and is hereinafter in connection with Fig. 3 explains in more detail.

By the fixed resistors R "and R_ and by the changing Resistors 14 and 20 form a bridge circuit. Here, the resistor 14 corresponds to that with the same Resistance element provided with reference symbols of FIG. 2, and resistor 20 represents the resistance of a transducer mounted on the spindle of the associated valve is.

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The resistors RV. and RU "are used to adjust the zero point and the scale display. The output of the bridge is fed to an operational amplifier 21 designed as an integrated component of the commercially available type SN 72709; the gain is determined or thereby adjusted by the ratio between the input resistance R ₄ and the feedback _{resistance R 5.}

The output of the amplifier 21 is fed to the common base connection of the transistors VT and VT ", which are complementary NPN and PNP transistors, for example of the type ZN 3704 and ZN 3702. Depending on the polarity of a disturbance of the bridge equilibrium, one of the transistors VT or VT “conductive and as a result the motor 7 will rotate the resistance element 14 until the bridge equilibrium is restored. The resistor R ₇ is used to limit the maximum power consumption of the motor.

The operating voltages supplied to terminals 22 and 23 are +6 V and> -6 V with respect to the common terminal capacitors C, and C ₁ - are provided in order to avoid disturbances or instability of the amplifier 21 caused by them. It has been shown in practical operation that up to 130 display devices can be operated with a power source which can deliver a current of 2 amps.

The structure of the display device is shown schematically in FIG. Before the critical area 26, which the Surrounding valves 27 and 28, Zener blocking elements 25 are arranged. " In the illustration of FIG. 4, the valve 27 is in the closed state and the valve 28 is in the open state. Of the Resistor 20, which is the transducer resistance for the

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Valve 28 has been shown here on an enlarged scale next to valve 28, with sliding contact 29 on the Valve spindle 30 is attached. A similar transducer resistor belongs to valve 27, but is not shown in the figure.

The connection to the display devices 2 shown in FIG. 4 is established by means of appropriate connecting elements and 3 manufactured.

In the event of a power failure, each remains of the display devices in the setting corresponding to the assigned valve.

10-9846 / 1,263

Claims (5)

- 6 claims [1. \ Device for displaying the operating position of a valve by means of a resistance transmitter, characterized in that that depending on the each position of the valve each assigned resistance value of the resistance transmitter • a motor (7) switched on with the corresponding direction of rotation which causes the setting of the display device (5). 2. Device according to claim 1, characterized in that the display device as a preferably colored bar (5) is executed, which is attached to the output shaft of the motor (7). , 3. Device according to claim 1 uncP 27 "marked is characterized by a such a choice of the coupling elements between the motor (7) and display device (5) that when changing between open and in the closed operating position of the valve, the bar (5) is rotated by 90. 4. Device according to one of the preceding claims, characterized in that the resistance transmitter as a variable Resistance, preferably as a rotary resistance (14), · is designed. 5. Device according to one of the preceding claims, characterized characterized in that the bar (5) serving as a display device in a schematic of the pipeline system Representative diagram arranged at the point of the pipeline in question corresponding to the assigned valve is (Fig. 1). 109846/1263