SHEET CONVEYANCE DEVICE CAPABLE OF DETECTING SHAPE OF SHEET, IMAGE FORMING APPARATUS, SHEET SHAPE DETECTING METHOD
First Claim
1. A sheet conveyance device comprising:
- a first conveyance member provided on an upstream side of an image forming position in a conveyance path along which a sheet is conveyed, the first conveyance member being rotationally driven in a driving cycle in which the first conveyance member enters a driven state where the first conveyance member is driven while decelerated in a stepped manner, and then the first conveyance member is decelerated to a stopped state;
a shape detecting portion including a light emitting portion and a light receiving portion, the light emitting portion being configured to emit light toward a detection position located between the first conveyance member and the image forming position in the conveyance path, the light extending in a width direction of the sheet perpendicular to the conveyance path, the light receiving portion being configured to receive the light that has been emitted from the light emitting portion and reflected on the sheet passing the detection position, and output a detection signal corresponding to an amount of received light, the shape detecting portion being configured to detect a shape of the sheet based on the detection signal;
a speed detecting portion configured to detect a rotation speed of the first conveyance member;
a determination processing portion configured to determine whether the first conveyance member is in an accelerated state or in a decelerated state, wherein in the accelerated state, the first conveyance member is accelerated from the stopped state to the driven state, and in the decelerated state, the first conveyance member is decelerated from the driven state to the stopped state; and
a switch control portion configured to, when the determination processing portion determines that the first conveyance member is in the accelerated state, switch an output interval at which the detection signal is output from the light receiving portion, to a first interval that corresponds to the rotation speed detected by the speed detecting portion, and when the determination processing portion determines that the first conveyance member is in the decelerated state, switch the output interval to a predetermined second interval.
1 Assignment
0 Petitions
Accused Products
Abstract
A sheet conveyance device includes a shape detecting portion, and a switch control portion. The shape detecting portion detects a shape of a sheet at a detection position located between a first conveyance member and an image forming position in a sheet conveyance path. The switch control portion, when the first conveyance member is determined to be in an accelerated state where it is accelerated from a stopped state to a driven state, switches an detection interval at which the shape of the sheet is detected by the shape detecting portion, to a first interval that corresponds to a rotation speed of the first conveyance member, and when the first conveyance member is determined to be in a decelerated state where it is decelerated from the driven state to the stopped state, switches the detection interval to a predetermined second interval.
8 Citations
12 Claims
-
1. A sheet conveyance device comprising:
-
a first conveyance member provided on an upstream side of an image forming position in a conveyance path along which a sheet is conveyed, the first conveyance member being rotationally driven in a driving cycle in which the first conveyance member enters a driven state where the first conveyance member is driven while decelerated in a stepped manner, and then the first conveyance member is decelerated to a stopped state; a shape detecting portion including a light emitting portion and a light receiving portion, the light emitting portion being configured to emit light toward a detection position located between the first conveyance member and the image forming position in the conveyance path, the light extending in a width direction of the sheet perpendicular to the conveyance path, the light receiving portion being configured to receive the light that has been emitted from the light emitting portion and reflected on the sheet passing the detection position, and output a detection signal corresponding to an amount of received light, the shape detecting portion being configured to detect a shape of the sheet based on the detection signal; a speed detecting portion configured to detect a rotation speed of the first conveyance member; a determination processing portion configured to determine whether the first conveyance member is in an accelerated state or in a decelerated state, wherein in the accelerated state, the first conveyance member is accelerated from the stopped state to the driven state, and in the decelerated state, the first conveyance member is decelerated from the driven state to the stopped state; and a switch control portion configured to, when the determination processing portion determines that the first conveyance member is in the accelerated state, switch an output interval at which the detection signal is output from the light receiving portion, to a first interval that corresponds to the rotation speed detected by the speed detecting portion, and when the determination processing portion determines that the first conveyance member is in the decelerated state, switch the output interval to a predetermined second interval. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. A sheet shape detecting method executed on a sheet conveyance device which includes a first conveyance member, a shape detecting portion, and a speed detecting portion, the first conveyance member being provided on an upstream side of an image forming position included in a conveyance path along which a sheet is conveyed, the first conveyance member being rotationally driven in a driving cycle in which the first conveyance member enters a driven state where the first conveyance member is driven while decelerated in a stepped manner, and then the first conveyance member is decelerated to a stopped state, the shape detecting portion including a light emitting portion and a light receiving portion, the light emitting portion being configured to emit light toward a detection position located between the first conveyance member and the image forming position in the conveyance path, the light extending in a width direction of the sheet perpendicular to the conveyance path, the light receiving portion being configured to receive light that has been emitted from the light emitting portion and reflected on the sheet passing the detection position, and output a detection signal corresponding to an amount of received light, the shape detecting portion detecting a shape of the sheet based on the detection signal, the speed detecting portion being configured to detect a rotation speed of the first conveyance member, the sheet shape detecting method comprising:
-
determining whether the first conveyance member is in an accelerated state or in a decelerated state, wherein in the accelerated state, the first conveyance member is accelerated from the stopped state to the driven state, and in the decelerated state, the first conveyance member is decelerated from the driven state to the stopped state; and when it is determined that the first conveyance member is in the accelerated state, switching an output interval at which the detection signal is output from the light receiving portion, to a first interval that corresponds to the rotation speed detected by the speed detecting portion, and when it is determined that the first conveyance member is in the decelerated state, switching the output interval to a predetermined second interval.
-
Specification