Valve Control Apparatus and Flow Rate Controller

• US 20090230339A1
• Filed: 05/08/2007
• Published: 09/17/2009
• Est. Priority Date: 05/08/2006
• Status: Active Grant

• Current Assignee: Surpass Industry Co., Ltd.
• Original Assignee: Surpass Industry Co., Ltd.
• Inventors: Nakamura, Atsutoshi, Ushigusa, Yoshihiro
• Granted Patent: US 8,172,199 B2
• Time in Patent Office: Days
• US Class Current: 251/129.50
• CPC Class Codes: F16K 31/04 using a motor
• CPC Class Codes: F16K 37/0083 by measuring valve parameters
• CPC Class Codes: G05D 7/0635 by action on throttling means G05D7/0688, G05D7/0694 take precedence
• CPC Class Codes: H02P 8/26 Memorising final pulse when stopping
• CPC Class Codes: H02P 8/42 characterised by non-stepper motors being operated step by step

Abstract

A valve control apparatus including a stepping motor coupled to a valve and a motor control unit for controlling the stepping motor is provided. The motor control unit includes a motor control section for applying drive pulses to the pulse motor, a counting section for counting the number of drive pulses applied to the pulse motor, a voltage-drop detecting section for detecting a voltage drop of a drive power supply for the motor control section, and a writing section for writing a count from the counting section in a nonvolatile memory if the voltage-drop detecting section detects the voltage drop.

Claims

1. A valve control apparatus for driving a valve for controlling the flow rate of a fluid flowing through a fluid channel, comprising:

a stepping motor coupled to the valve; and

a motor control unit for controlling the stepping motor;

wherein the motor control unit comprises;

a motor control section for applying drive pulses to the pulse motor;

a counting section for counting the number of drive pulses applied to the pulse motor;

a voltage-drop detecting section for detecting a voltage drop of a drive power supply for the motor control section; and

a writing section for writing a count from the counting section in a nonvolatile memory if the voltage-drop detecting section detects the voltage drop.

2. The valve control apparatus according to claim 1, further comprising a period-adjusting section for extending a drive termination period to a predetermined period of time or more, the drive termination period being from voltage-drop detection at which the voltage-drop detecting section detects the voltage drop to drive termination at which the driving of the motor control section stops.

3. The valve control apparatus according to claim 1, wherein the motor control section executes return-to-origin control for returning the valve to an origin at the start of driving of the pulse motor by reading the count written in the nonvolatile memory and driving the pulse motor based on the count.

4. A flow rate controller comprising:

a valve for controlling the flow rate of a fluid flowing through a fluid channel; and

the valve control apparatus according to claim 1.

5. A motor control unit comprising:

a motor control section for applying drive pulses to the pulse motor;

a counting section for counting the number of drive pulses applied to the pulse motor;

a voltage-drop detecting section for detecting a voltage drop of a drive power supply for the motor control section; and

a writing section for writing a count from the counting section in a nonvolatile memory if the voltage-drop detecting section detects the voltage drop.

6. A pulse motor apparatus comprising:

a pulse motor; and

the motor control unit according to claim 5, which controls the pulse motor.