Rotary valve

Patent metadata

Field	Value
Publication number	US-2016291607-A1
Application number	US-201615086135-A
Country	US
Kind code	A1
Filing date	Mar 31, 2016
Priority date	Mar 31, 2015
Publication date	Oct 6, 2016
Grant date	—

Abstract

A valve opening setpoint corrector and a correction table storage are provided in a flow rate controlling valve. A correction table indicating valve opening correction values corresponding to combinations of amounts of opening of a valve and front-back differential pressures across the valve is stored in the correction table storage. In the valve opening setpoint corrector a correction value acquirer acquires, from the correction table, the valve opening correction value α that corresponds to the inputted measured value of the valve and front-back differential pressure across the valve and sends it to the setpoint corrector, as a correction value that takes into account the amount of twist in the valve rod. The setpoint corrector corrects, by the correction value taking into account the amount of twist in the valve rod, the valve opening setpoint from the air conditioning controller, sending this corrected valve opening setpoint to the valve opening controller.

First claim

We claim:

1 . A rotary valve comprising:
a valve unit adjusting the amount of opening of a flow path through which a fluid flows; a valve rod linked to the valve unit; a driver rotating the valve rod; a valve opening detector detecting a measured opening of the valve unit from a rotational position of the valve rod; an opening controller using, as a valve opening measured value, a measured amount of opening of the valve unit, detected by the valve opening detector, to control a rotation quantity of the valve rod by the driving portion so that this valve opening measured value will match a valve opening setpoint; and a valve opening setpoint corrector correcting the valve opening setpoint by a correction value that takes into account an amount of twist of the valve rod.

2 . The rotary valve as set forth in claim 1 , further comprising:
a differential pressure detector detecting, as a front-back differential pressure across the valve unit, a differential pressure between a pressure of a fluid on a primary side of the valve unit and a pressure of a fluid on a secondary side of the valve unit, wherein: the valve opening setpoint corrector calculates a correction value that takes into account an amount of twist of the valve rod, based on a measured opening of the valve unit, detected by the valve opening detector, and a front-back differential pressure across the valve unit, detected by the differential pressure detector, to correct, by the calculated correction value, the valve opening setpoint.

3 . The rotary valve as set forth in claim 2 , further comprising:
a correction table indicating a valve opening correction value corresponding to a combination of an amount of opening of the valve unit and a front-back differential pressure across the valve unit, wherein: the valve opening setpoint corrector acquires, from the correction table, a valve opening correction value corresponding to a measured opening of the valve unit, detected by the valve opening detector, and a front-back differential pressure across the valve unit, detected by the differential pressure detector, and uses the acquired valve opening correction value as the correction value that takes into account an amount of twist of the valve rod.

4 . The rotary valve as set forth in claim 2 , further comprising:
a first correction table indicating a first valve opening correction value corresponding to a combination of an amount of opening of the valve unit and a front-back differential pressure across the valve unit; and a second correction table indicating a second valve opening correction value corresponding to a combination of an amount of opening of the valve unit and a front-back differential pressure across the valve unit; wherein the valve opening setpoint corrector, if the change is in the direction wherein the valve opening setpoint is decreasing, acquires, from the first correction table, the first valve opening correction value that corresponds to the measured opening of the valve unit, detected by the valve opening detector, and the front-back differential pressure across the valve unit, detected by the differential pressure detector, is acquired from the correction table for a change in the opening direction, and if the change is in the direction wherein the valve opening setpoint is increasing, acquires, from the second correction table, the second valve opening correction value that corresponds to the measured opening of the valve unit, detected by the valve opening detector, and the front-back differential pressure across the valve unit, detected by the differential pressure detector, is acquired from the correction table for a change in the opening direction, and uses, as the correction value that takes into account the twist of the valve rod, the valve opening correction value that has been acquired.

5 . The rotary valve as set forth in claim 4 , wherein:
each of the first valve opening correction values set in the first correction table is a negative value; and each of the second valve opening correction values set in the second correction table is a positive value.

Assignees

• Azbil Corp

Inventors

• Ohashi Tomofumi
• Someya Hideaki

Classifications

• F24F11/84

  using valves · CPC title

• F16K37/0041

  for measuring valve parameters (F16K37/0033 takes precedence) · CPC title

• F16K37/0025

  Electrical or magnetic means (F16K37/0075 takes precedence) · CPC title

• G05D7/0617

  specially adapted for fluid materials · CPC title

• F24F5/0003

  Exclusively-fluid systems · CPC title