Device and method for belt speed control, and image forming apparatus
AssigneeRicoh Company, Ltd.
InventorYoshihiro Sakai
Life of this patent
Estimating the term…
Abstract
A scale including equally spaced marks is attached to a belt in a direction of movement of the belt such that a gap is formed between a first end and a second end of the scale. A first sensor and a second sensor detect the marks on the scale and output first signals and second signals respectively upon detecting the marks. The first sensor and the second sensor are located at different positions along the direction. A controlling unit controls the speed based on any one of the first signals and the second signals according to a position of the gap detected by the first sensor and the second sensor.
Claims19
A device for controlling speed of a belt, wherein a scale including a plurality of equally spaced marks is attached to the belt in a direction of movement of the belt such that a gap is formed between a first end and a second end of the scale, the device comprising:
- a first sensor configured to detect the marks on the scale and output a first signal upon detecting a mark among the marks;
- a second sensor configured to detect the marks on the scale and output a second signal upon detecting a mark among the marks, wherein the first sensor and the second sensor are located at different positions along the direction;
- and
- a controlling unit that controls the speed based on, any one of the first signals and the second signals according to a position of the gap detected by the first sensor and the second sensor.
An image forming apparatus comprising:
- an image forming unit that forms images by movement of a belt, wherein a scale including a plurality of equally spaced marks is attached to the belt in a direction of movement of the belt such that a gap is formed between a first end and a second end of the scale;
- and
- a device that controls speed of the belt, including
- a first sensor configured to detect the marks on the scale and output a first signal upon detecting a mark among the marks;
- a second sensor configured to detect the marks on the scale and output a second signal upon detecting a mark among the marks, wherein the first sensor and the second sensor are located at different positions along the direction;
- and
- a controlling unit that controls the speed based on any one of the first signals and the second signals according to a position of the gap detected by the first sensor and the second sensor.
A method for controlling speed of a belt, wherein a scale including a plurality of equally spaced marks is attached to the belt in a direction of movement of the belt such that a gap is formed between a first end and a second end of the scale, the method comprising:
- detecting the marks on the scale at a first position;
- detecting the marks on the scale at a second position, wherein the first position and the second position are located at different positions along the direction;
- and
- controlling the speed based on detection results at any one of the first position and the second position according to a position of the gap detected at any one of the first position and the second position.
A device for controlling speed of a belt, wherein a scale including a plurality of equally spaced marks is attached to the belt in a direction of movement of the belt such that a gap is formed between a first end and a second end of the scale, the device comprising:
- first detecting means for detecting the marks on the scale and outputting a first signal upon detecting a mark among the marks;
- second detecting means for detecting the marks on the scale and outputting a second signal upon detecting a mark among the marks, wherein the first detecting means and the second detecting means are located at different positions along the direction;
- and
- controlling means for controlling the speed based on any one of the first signals and the second signals according to a position of the gap detected by the first detecting means and the second detecting means.
Dependencies are inferred from the claim text.