US 12,085,871 B2
Image forming apparatus with suppression of light quality attenuation
Tsuyoshi Ogawa, Tokyo (JP); Shinichi Nishida, Kanagawa (JP); Tetsushi Uneme, Kanagawa (JP); and Masahiro Suetsugu, Kanagawa (JP)
Assigned to CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on Dec. 8, 2022, as Appl. No. 18/077,563.
Claims priority of application No. 2021-203077 (JP), filed on Dec. 15, 2021; and application No. 2021-206459 (JP), filed on Dec. 20, 2021.
Prior Publication US 2023/0185215 A1, Jun. 15, 2023
Int. Cl. G03G 15/08 (2006.01); G01F 23/292 (2006.01)
CPC G03G 15/0862 (2013.01) [G01F 23/292 (2013.01)] 17 Claims
OG exemplary drawing
 
1. An image forming apparatus comprising:
a container configured to accommodate a developer; and
a sensor configured to output an output signal depending on an amount of the developer in the container, wherein the sensor includes a light emitting element and a light receiving element which are provided outside the container, and a light guide provided on a wall surface of the container and configured to guide light, emitted by the light emitting element, toward the light receiving element through an inside space of the container,
wherein the light guide includes:
a first projected portion projected to an outside of the container relative to the wall surface in a first direction intersecting with a direction of gravity and having an incident surface on which the light emitted by the light emitting element is incident and which is provided at an end portion of the first projected portion with respect to the first direction;
a second projected portion projected to an inside of the container relative to the wall surface in the first direction and through which the light incident on the first projected portion is emitted to the inside space of the container, wherein an upper surface of the second projected portion is positioned above a first virtual rectilinear line that is parallel to and is on an upper surface of the first projected portion as viewed in a direction intersecting with both the first direction and the direction of gravitation,
a third projected portion projected to the inside of the container relative to the wall surface in a second direction intersecting with the direction of gravity and on which the light emitted to the inside space of the container is incident; and
a fourth projected portion projected to the outside of the container relative to the wall surface in the second direction and having a light emergent surface from which the light incident on the third projected portion is emitted toward the light receiving portion and which is provided on an end portion of the fourth projected portion with respect to the second direction,
wherein an upper surface of the third projected portion is positioned above a second virtual rectilinear line that is parallel to and is on an upper surface of the fourth projected portion in a case where the upper surface of the third projected portion is viewed in a direction crossing the second direction and the direction of gravitation,
wherein the first projected portion and the second projected portion are configured such that a direction in which the light travels from the outside of the container to the inside of the container through the first projected portion and the second projected portion is a direction intersecting with the direction of gravity, and
wherein the third projected portion and the fourth projected portion are configured such that a direction in which the light travels from the inside of the container to the outside of the container through the third projected portion and the fourth projected portion is a direction intersecting with the direction of gravity.