Focal-plane shutter for digital camera

A focal plane shutter for a digital camera comprising:

• a first blade and a second blade which are individually arranged in two blade chambers configured such that a space between a shutter ground plate and an auxiliary ground plate is partitioned by an intermediate plate;
• a driving member for the first blade and a driving member for the second blade which are respectively coupled to the first blade and the second blade, and respectively rotated by urging force of a driving spring for the first blade and the urging force of a driving spring for the second blade to cause the first blade and the second blade to perform an exposure operation, if a lock caused by a locking member for the first blade and a lock caused by a locking member for the second blade are released in order;
• a setting member which is located at an initial position retreated out of operation loci of the two driving members when the first blade and the second blade perform an exposure operation, starts a setting operation from the initial position if the exposure operation is completed, and rotates the two driving members to positions capable of being locked to the two locking members against the urging forces of the two driving springs so as to return the driving members to the initial position before photographing;
• an unlocking unit for the first blade and an unlocking unit for the second blade which are respectively attracted to and held by iron core members of an electromagnet for the first blade and an electromagnet for the second blade when an electric current is applied to coils of the two electromagnets, and are respectively separated from the iron core member against an urging force of a release spring for the first blade and an urging force of a release spring for the second blade to individually release the lock of the two driving members by the two locking members, if application of an electric current to the coils of the two electromagnets is cut off in order;
• a holding unit which is configured to be operated so as to interlock with the setting operation of the setting member, pushes the two unlocking units against the urging forces of the two release springs to bring the unlocking unit into contact with the two iron core members, and is operated out of the operation loci of the two unlocking units if an electric current is applied to the coils of the two electromagnets;
• an electromagnetic device having a reciprocable moving element;
• and
• a deterring unit which is configured to be operated to reciprocate by the moving element, and is advanced and retreated in the operation locus of the unlocking unit for the second blade,
• wherein, when the deterring unit is advanced into the operation locus of the unlocking unit for the second blade in the case where the unlocking unit for the second blade comes into contact with the iron core member of the electromagnet for the second blade, the holding unit is operated out of the operation loci of the two unlocking units without application of an electric current to the coils of the two electromagnets, and, the deterring unit deters the operation of the unlocking unit for the second blade which is separated from the iron core member of the electromagnet for the second blade before the lock of the driving member for the second blade by the locking member for the second blade is released, and then, if the electromagnetic device operates the deterring unit out of the operation locus of the unlocking unit for the second blade, the unlocking unit for the second blade releases the lock of the driving member for the second blade by the locking member for the second blade.