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US 7,679,231 B2Granted
Driving device and light amount controller
AssigneeCanon Kabushiki Kaisha
InventorHiromu Yasuda
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AssigneeCanon Kabushiki Kaisha
InventorHiromu Yasuda
Estimating the term…
A driving device which makes it possible to reduce the moment of inertia of a rotor and increase torque. A magnet is formed to have a hollow cylindrical shape and has magnetized sections which are magnetized to have alternately different poles in a circumferential direction thereof. A coil is wound coaxially with the magnet and is disposed in axially side-by-side relation to the magnet. A stator yoke is formed of a soft magnetic material and fixes the magnet and the coil. A rotor yoke is formed of a soft magnetic material, and has magnetic pole portions formed in opposed relation to the magnetized sections, for being magnetized by the coil. The rotor yoke is supported in a manner rotatable with respect to the stator yoke. An rotation restricting part limits a range of rotation of the rotor yoke within a predetermined angle.
A driving device comprising:
A light amount control device comprising:
Dependencies are inferred from the claim text.
Drawings are temporarily unavailable. Open the PDF at USPTO
From the US filing history. Foreign family members aren’t listed.
Machines adapted to function as torque motors, i.e. to exert a torque
Blade or disc rotating or pivoting about axis normal to its plane: two separate members moving in opposite directions
More than two members: each moving in one direction to open and then in opposite direction to close, e.g. iris type
With armatures: pivoting armatures
About 1 year 7 months of term left · ends 2 Jun 2028 (estimated)
1. Field of the Invention
The present invention relates to a driving device configured to rotate a rotor yoke, and a light amount controller incorporating the driving device as a drive source thereof.
2. Description of the Related Art
FIG. 1 is an exploded perspective view of a light amount controller according to a first embodiment of the present invention;
FIG. 2 is a cross-sectional view in the axial direction of the light amount controller in FIG. 1 in an assembled state thereof;
FIG. 3A is a front view of the light amount controller in FIG. 2 with shutter blades thereof closed;
The present invention will now be described in detail with reference to the drawings showing preferred embodiments thereof.
First, a description will be given of a first embodiment of the present invention.
FIG. 1 is an exploded perspective view of a light amount controller according to the first embodiment. FIG. 2 is a cross-sectional view in the axial direction of the light amount controller in FIG. 1 in an assembled state thereof. FIG. 3A is a front view of the light amount controller with shutter blades thereof closed. FIG. 3B is a front view of the light amount controller with the shutter blades thereof open.