发明授权
- 专利标题: Camera
- 专利标题(中): 相机
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申请号: US921762申请日: 1992-07-30
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公开(公告)号: US5257056A公开(公告)日: 1993-10-26
- 发明人: Jiro Kazumi
- 申请人: Jiro Kazumi
- 申请人地址: JPX Tokyo
- 专利权人: Canon Kabushiki Kaisha
- 当前专利权人: Canon Kabushiki Kaisha
- 当前专利权人地址: JPX Tokyo
- 优先权: JPX3-194135 19910802
- 主分类号: G03B9/08
- IPC分类号: G03B9/08 ; G03B9/18 ; G03B9/34 ; G03B9/62 ; G03B17/20
摘要:
A camera having a shutter device including leading and trailing curtains includes a first switch arranged to detect the ready-to-travel state and the travel-completed state of the leading curtain, a second switch arranged to detect the ready-to-travel state and the travel-completed state of the trailing curtain, and a decision circuit arranged to determine that the shutter device is abnormal, either when the ready-to-travel state of the leading curtain is not detected by the first switch or when that of the trailing curtain is not detected by the second switch, before an operation of the shutter device. The decision circuit also determines that the shutter device is abnormal, after completion of control over the travels of the leading and trailing curtains by the shutter device, if the travel-completed state of the leading curtain is not detected by the first switch within a predetermined period of time after the travel-completed state of the trailing curtain is detected by the second switch.
公开/授权文献
- US4268216A Load lifting and carrying machine 公开/授权日:1981-05-19