Hand 2, turning about fixed axis A, is linked to Bourdon tube 1 which is connected to the item whose pressure is to be regulated. Link 15 is connected by turning pairs C and D to hand 2 and to lever 3 which, in turn, is connected by turning pair B to the rod of bellows 13 and carries shutter a. When the pressure rises in the item being regulated, hand 2 turns counterclockwise and shutter a is retracted from nozzle 4 to which compressed air is delivered through tube 5 and flow-control valve 6. Compressed air is also delivered through flow-control valve 9 to the chamber of valve 8 whose ball is linked to bellows 7. The chamber of bellows 7 is connected to nozzle 4. The chamber of valve 8 is connected to the atmosphere and to the membrane chamber of servomotor 10. As shutter a is retracted from nozzle 4, the pressure in bellows 7 drops and the ball of valve 8 is raised, closing off air discharge to the atmosphere. After this, pressure on the membrane of servomotor 10 increases and valve 11 is closed to some extent, reducing the supply of heat-carrying agent to the system. The increase in pressure compresses bellows 12. At this, bellows 13 is stretched, moving shutter a toward nozzle 4. Upon the deformation of bellows 12 and 13, the pressure of the air in them increases. As a result, a part of the air is released through flow-control valve 14 to the atmosphere, and shutter a smoothly returns to its initial position. When the pressure in the system drops, the elements of the regulator operate in the reverse direction.
$4093$EHP,Rg$