Capping method and capping apparatus

• US 20020148205A1
• Filed: 03/15/2002
• Published: 10/17/2002
• Est. Priority Date: 04/13/2001
• Status: Active Grant

• Current Assignee: Shibuya Kogyo Company Limited, the united states of america as represented by the secretary of the navy
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Takebe, Minoru, Yoshida, Kenichiro, Kasai, Mitsuru
• Granted Patent: US 7,024,837 B2
• Time in Patent Office: Days
• US Class Current: 53/490
• CPC Class Codes: B67B 3/20 by applying and rotating preformed threaded caps forming threads in situ by resilient deforming means B67B3/16, by rotary capping heads B67B3/18
• CPC Class Codes: B67B 3/2093 whereby the applied torque limit is varied
• CPC Class Codes: B67B 3/26 Applications of control, warning, or safety devices in capping machinery

Abstract

A screw capper 1 includes a capping head 6 which grips a cap 5, a servo motor 7 which rotates the capping head, a voltmeter 10 which measures the torque of the capping head, an encoder 11 which detects the rotational angle of the capping head, and a control device 8 which controls the servo motor. In the screw capper, when whether rotational fastening is acceptable is to be determined during the rotational fastening, the measured value of the encoder is measured from a predetermined measurement starting point until a rotational fastening completion point, and if the measured rotational angle is in the range of an acceptable decision angle which is set in advance, it is determined that the rotational fastening has been acceptably performed, whereas if the measured rotational angle is not in the range of the acceptable decision angle, it is determined that the rotational fastening is unacceptable.

In the screw capper, defective rotational fastening can be detected, and reductions in costs can be realized compared to a case where a device for detecting such defective rotational fastening is separately provided.

Claims

1. A capping method which uses a capping head which retains a cap, and a motor which rotates the capping head, the capping method causing the cap retained by the capping head to rotate in a cap-closing direction and rotationally fastening the cap to a container with a predetermined cap-closing torque,

characterized in that the capping method comprising the steps of:

measuring a rotational angle of the capping head from a predetermined measurement starting point until a completion of rotational fastening; and

determining whether the rotational fastening is acceptable, according to whether the rotational angle is within a range of an acceptance decision angle which is set in advance.

2. A capping method according to claim 1, wherein the measurement starting point is an engagement starting position at which when a screw thread portion of the cap and a screw thread portion of the container are rotated relatively to each other, leading ends of both screw thread portions come into contact with each other.

3. A capping method according to claim 1, wherein the measurement starting point is a point of transfer from temporary fastening for rotationally fastening the cap with a low torque to final fastening for rotationally fastening the cap with a higher torque than the temporary fastening does.

4. A capping method according to claim 1, further comprising:

a step of effecting temporary fastening for rotationally fastening the cap with a low torque; and

a step of effecting final fastening for rotationally fastening the cap with a higher torque than the temporary fastening does,

the measurement starting point being a time point at which a rotational speed becomes lower than a predetermined value during the temporary fastening.

5. A capper comprising a capping head which grips a cap, a motor which rotates the capping head, a control device which controls the motor to rotate the cap in a cap-closing direction and rotationally fasten the cap to a container with a predetermined cap-closing torque,

characterized in that the capper provides rotational angle detecting means for measuring a rotational angle of the capping head, a value measured by the rotational angle detecting means being inputted to the control device, and the control device finding the rotational angle by measuring the value measured by the rotational angle detecting means, from a predetermined measurement starting point until a completion of rotational fastening, and determining whether the rotational fastening is acceptable, according to whether the rotational angle is within a range of an acceptance decision angle which is set in advance.