SYNCHRONIZATION CONTROL SYSTEM

• US 20090005910A1
• Filed: 08/29/2008
• Published: 01/01/2009
• Est. Priority Date: 03/01/2006
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Akita, Tadashi
• Granted Patent: US 7,586,284 B2
• Time in Patent Office: Days
• US Class Current: 700/275
• CPC Class Codes: B23P 19/066 by electrical means
• CPC Class Codes: G01L 5/24 for determining value of torque or twisting moment for tightening a nut or other member which is similarly stressed
• CPC Class Codes: G05B 19/4141 characterised by a controller or microprocessor per axis
• CPC Class Codes: G05B 2219/50218 Synchronize groups of axis, spindles
• CPC Class Codes: G05B 2219/50222 Stop machines, actuators until others reach common synchronization point

Abstract

A synchronization control system includes plural controlling object apparatuses connected through first and second wired OR lines. Each controlling object apparatus includes a function of switching an output to the first wired OR line from a first state to a second state in an odd numberth synchronization waiting state and switching an output to the second wired OR line from the first state to the second state in an even numberth synchronization waiting state. A control apparatus determines an odd numberth synchronization in response to changing of the first wired OR line from the first state to the second state when all the controlling object apparatuses enter the odd numberth synchronization waiting state, and determines an even numberth synchronization in response to changing of the second wired OR line from the first state to the second state when all the controlling object apparatuses enter the even numberth synchronization waiting state.

Claims

1. A synchronization control system comprising:

plural controlling object apparatuses mutually connected through a first wired OR line and a second wired OR line; and

a control apparatus that controls the plural controlling object apparatuses while synchronizing them,

wherein each of the controlling object apparatuses includes;

a counter that increments a count value by one every time entering a synchronization waiting state; and

a function of switching an output to the first wired OR line from a first state to a second state in an odd numberth synchronization waiting state in which the counter value is an odd number, and switching an output to the second wired OR line from the first state to the second state in an even numberth synchronization waiting state in which the counter value is an even number, and

wherein the control apparatus determines an odd numberth synchronization in response to changing of the state of the first wired OR line from the first state to the second state when all the controlling object apparatuses enter the odd numberth synchronization waiting state, and determines an even numberth synchronization in response to changing of the state of the second wired OR line from the first state to the second state when all the controlling object apparatuses enter the even numberth synchronization waiting state.

2. A synchronization control system according to claim 1,

wherein each of the controlling object apparatuses switches the output to the second wired OR line from the second state to the first state in the odd numberth synchronization waiting state, and switches the output to the first wired OR line from the second state to the first state in the even numberth synchronization waiting state.

3. A synchronization control system according to claim 1,

wherein at least one of the first and second wired OR lines is plurally provided, and

wherein the control apparatus uses the wired OR lines plurally provided while switching them in response to increments in the count value of the counter.

4. A synchronization control system according to claim 1,

wherein each of the controlling object apparatuses, before start of a series of synchronization controls or after completion thereof, sets the count value of the counter to 0, sets the output to the first wired OR line to the first state, and sets the output to the second wired OR line to the second state.

5. A synchronization control system according to claim 1,

wherein each of the controlling object apparatuses outputs signals to the first and second wired OR lines from an open collector or an open drain, and

wherein the first state is an on-state and the second state is an off-state.

6. A synchronization control system according to claim 1,

wherein the controlling object apparatus is a screw tightening apparatus, and

wherein the control apparatus changes operation states of the plural screw tightening apparatuses step by step in every synchronization.

7. A synchronization control system according to claim 6,

wherein the operation state of the screw tightening apparatus includes a step-by-step increase in tightening torque.

8. A synchronization control system according to claim 1, wherein the controlling object apparatus is an actuator that drives an object, and

wherein the control apparatus controls step by step a position of the object driven by the plural actuators in every synchronization.