RU61816U1 - ELECTRIC PNEUMATIC CONTROL DEVICE - Google Patents

Abstract

The electro-pneumatic control device relates to the field of automation of control of pipeline fittings. mainly for controlling pneumatic actuators of ball valves of gas pipelines. The device can be used to control pneumatic actuators or pneumohydraulic actuators operating on the pressure energy of compressed gas from main pipelines, on compressed gas cylinders or gas of a solid fuel gas generator. The device contains electromagnets and reed switches in a flameproof enclosure made of non-magnetic material and pneumatic valves on a panel with working gas supply channels, permanent magnets and a rotary shaft. Steel shielding shutters are installed on the rotary shaft, which are located in the gap between the fixed reed switches and the permanent magnets fixed opposite the reed switches. The implementation of shielding shutters that overlap the magnetic field between the reed switches and permanent magnets provides a clear and stable operation of the reed switches regardless of the change in the magnetic field of the permanent magnets due to aging and hysteresis.

Description

The utility model relates to the field of automation of control of valves of pipelines and relates to an electro-pneumatic control device mainly for controlling pneumatic actuators of ball valves of gas pipelines.

An electro-pneumatic control device can also be used to control pneumatic actuators and pneumohydraulic actuators of gas-compressor fittings for oil pumping stations, in the chemical and shipbuilding industries.

Known electro-pneumatic control device containing electromagnets and reed switches in a flameproof enclosure of non-magnetic material and pneumatic valves on a panel with working gas supply channels, a rotary shaft in the panel and permanent control magnets that act on the reed switches during their movement. Permanent magnets are located at the ends of the rotary levers, and the rotary shaft is equipped with a rocker with the possibility of impact when turning on the levers (1).

Permanent magnets that are located on the pivoting levers approach (or are removed) to the reed switches when turning the shaft in one direction or another. At the same time, permanent magnets turn on (or turn off) the reed switches, ensuring the ball stop of the ball valve in the extreme (predetermined) positions. Over time, there is a fuzzy, unstable operation of the reed switches. There is an overrun or an unavailability of the position of the ball of the ball valve relative to the specified positions. Apparently this is due to the instability of the magnetic field of permanent magnets with time and magnet hysteresis.

Known electro-pneumatic control device containing electromagnets and reed switches in a flameproof enclosure of non-magnetic

material and pneumatic valves on the panel with working gas supply channels, as well as a rotary shaft with permanent control magnets which is located on the panel with the possibility of magnets acting on the reed switches (2).

Permanent magnets, which are located on the rotation of the shaft, approach (or are removed) to the reed switches when turning the shaft in one direction or another. In this case, the permanent magnet turns on (or turns off) the reed switches, ensuring that the ball of the ball valve stops in the extreme (predetermined) positions. Over time, there is a fuzzy, unstable operation of the reed switches. There is an overrun or an unavailability of the position of the ball of the ball valve relative to the specified positions. Apparently this is due to a change in the magnetic fields of permanent magnets due to aging or hysteresis.

The objective of this utility model is to create such an electro-pneumatic control device that would ensure a clear, stable operation of the reed switches regardless of changes in the magnetic popeys of permanent magnets.

The problem is solved in that in an electro-pneumatic control device containing electromagnets and reed switches in a flameproof enclosure made of non-magnetic material and pneumatic valves on a panel with working gas supply channels, permanent control magnets and a rotary shaft, steel shielding shutters are installed on the shaft, which are located in the gap between fixed mounted reed switches and fixed fixed permanent magnets, according to the proposal, steel shielding shutters are made motionless.

The essence of the proposal is illustrated by examples of specific performance and drawings, in which: Fig.1 is a side view in section, Fig.2 is a top view with the casing removed.

The electro-pneumatic control device includes a base panel 1 (figure 2), a flameproof enclosure 2, consisting of a housing

3 and covers 4. In the housing 3, two electromagnets 5 and 6 are installed (Fig. 3). An anchor 7 (Fig. 2) of each electromagnet is connected with a pusher 9 to a lever 10, which is connected through a screw 12 with a lock nut 14 to a lever 15 and a pusher 17 of a pneumatic valve 19 and 20 (Fig. 3).

Explosion-proof shell 2 (figure 2) is made of non-magnetic material. In the flameproof enclosure 2, two reed switches 21 and 22 (FIG. 3) and a switching chill are fixedly mounted 23. In the base panel 1 there is a rotary shaft 25 (FIG. 2), at one end of which a groove of day 26 of engagement with the pneumatic drive shaft is made. Instead of a groove at the end of the shaft, a pin can be made. An indicator arrow 27 is installed at the other end of the shaft 25, covered by a glass 28 of the casing 29. A holder 30 is mounted on the shaft 25, on which sliding shielding shutters 31, 32 are placed.

On the bracket attached to the housing 3, are mounted stationary opposite the reed switches 21 and 22, a permanent magnet 33 (figure 2). Sliding shielding steel shutters 31, 32 are located in the gap between the fixed mounted reed switches 21 and 22 (figure 3) and the fixed magnets 33 (figure 2).

The electro-pneumatic control device operates as follows:

Together with the pneumatic drive shaft, the shaft 25 is rotated with the holder 30 fixed on it and the shutters 31, 32. When the shaft 25 is rotated, for example, by a 90 ° angle, the shutters 31, 32 open the magnet 33 located opposite the reed switch 21. The magnet 33 acts on the reed switch 21 and opens the power supply circuit of the electromagnet 5. The pneumatic valve 19 is activated and the pneumatic actuator stops. At the same time, another magnet located opposite the reed switch 22 is closed by a shutter 31 and does not affect the reed switch 22. The reed switch 22 switches and turns on the power circuit of the electromagnet 6, preparing it to be switched on remotely from the control room control panel.

The post of signaling remotely from the control room control panel to the electromagnet 6 is actuated by a pneumatic valve 20 and the actuator operates in the opposite direction.

Magnets 33 are so close to the reed switches that they even work when the magnetic field is significantly weakened. The implementation of shielding shutters that overlap the magnetic field between the reed switches and permanent magnets allows for a clear and stable operation of the reed switches regardless of changes in the magnetic trends of permanent magnets due to aging and hysteresis. This, in turn, ensures a clear and stable position of the ball of the ball storage in the final (predetermined) positions.

Sliding shutters provide adjustment of the moment of operation of the reed switches to ensure a given position of the ball of the ball valve.

From available sources of information, the authors did not identify a device with similar features.

The proposed device is feasible in serial production of a machine-building enterprise.

The device uses widely known materials, unique materials or equipment for the manufacture and testing of such a device is not required.

The device can be used to control pneumatic actuators, or pneumohydraulic actuators operating on the pressure energy of compressed gas from main pipelines, on compressed gas cylinders and gas of solid fuel gas generators.

Information sources:

1. RU 2171406 C1, 12/15/2000

2. RU 2126497 C1. 05/07/1998

Claims (1)

An electro-pneumatic control device containing an electromagnet and reed switches in a flameproof enclosure made of non-magnetic material and pneumatic valves on a panel with working gas supply channels, permanent control magnets and a rotary shaft, steel shielding shutters are installed on the shaft, which are located in the gap between the fixed reed switches and the fixed fixed magnets and fixedly mounted permanent magnets, characterized in that the steel shielding curtains are made p Sliding.