1. An image forming apparatus comprising:
an image carrier that includes a first rotating shaft and is rotatable around the first rotating shaft, or that has a belt-shape and is wound around a belt support unit that includes a second rotating shaft and is rotatable around the second rotating shaft;
a contact unit that is capable of coming in contact with a surface of the image carrier;
a biasing unit that applies a biasing force to either one of the image carrier and the contact unit to be brought into contact with another one of the image carrier and the contact unit;
a thickness-information acquiring unit that acquires thickness information of a recording sheet;
a distance adjusting unit that adjusts an inter-unit distance between the contact unit and either one of the first rotating shaft and the second rotating shaft by moving the either one of the image carrier and the contact unit by applying an opposing force to the either one of the image carrier and the contact unit against the biasing force based on the thickness information; and
a data storage unit that stores therein data indicating a relationship between the thickness information and an inter-unit distance change amount, the inter-unit distance change amount being a change in the inter-unit distance when a state where the distance adjusting unit does not apply the opposing force against the biasing force and the recording sheet is not fed into a nip between the image carrier and the contact unit is shifted to a state where the recording sheet is passed through the nip without the distance adjusting unit applying the opposing force against the biasing force, wherein
the distance adjusting unit adjusts the inter-unit distance based on the thickness information and the data stored in the data storage unit to transfer a visible image formed on the surface of the image carrier onto the recording sheet passed through the nip.
2. The image forming apparatus according to claim 1, wherein the distance adjusting unit adjusts the inter-unit distance so that an inter-unit distance difference between a state where the distance adjusting unit does not apply the opposing force against the biasing force and the recording sheet is not fed into the nip and a state where the distance adjusting unit adjusts the inter-unit distance by applying the opposing force against the biasing force but the recording sheet is not fed into the nip is equal to or less than the inter-unit distance change amount.
3. The image forming apparatus according to claim 1, wherein
the distance adjusting unit includes a sheet conveying path provided in either one of an upstream side and a downstream side of a contact portion between the image carrier and the contact unit in a sheet conveying direction, the sheet conveying path being structured so that a force is applied to the either one of the image carrier and the contact unit to widen the inter-unit distance by stiffness of the recording sheet, and
the distance adjusting unit adjusts the inter-unit distance so that an inter-unit distance difference between a state where the distance adjusting unit does not apply the opposing force against the biasing force and the recording sheet is not fed into the nip and a state where the distance adjusting unit adjusts the inter-unit distance by applying the opposing force against the biasing force but the recording sheet not fed into the nip is equal to or more than a value indicated by the thickness information.
4. The image forming apparatus according to claim 1, further comprising:
a distance-change detector that detects a change in the inter-unit distance; and
a changing unit that, when there occurs a difference between the inter-unit distance change amount stored in the data storage unit and the inter-unit distance change amount detected by the distance-change detector in the state where the recording sheet is passed through the nip without the distance adjusting unit applying the opposing force against the biasing force, changes the inter-unit distance change amount stored in the data storage unit based on the inter-unit distance change amount detected by the distance-change detector.
5. The image forming apparatus according to claim 1, wherein the distance adjusting unit is configured so that the inter-unit distance is adjusted only when the thickness information indicates a predetermined value or more.
6. The image forming apparatus according to claim 1, wherein the distance adjusting unit adjusts the inter-unit distance by moving the contact unit.
7. An image forming apparatus comprising:
an image carrier that includes a first rotating shaft and is rotatable around the first rotating shaft, or that has a belt-shape and is wound around a belt support unit that includes a second rotating shaft and is rotatable around the second rotating shaft;
a contact unit that is capable of coming in contact with a surface of the image carrier;
a biasing unit that applies a biasing force to either one of the image carrier and the contact unit to be brought into contact with another one of the image carrier and the contact unit;
a distance adjusting unit that adjusts an inter-unit distance between the contact unit and either one of the first rotating shaft and the second rotating shaft by moving the either one of the image carrier and the contact unit by applying an opposing force to the either one of the image carrier and the contact unit against the biasing force; and
a distance-change detector that detects an inter-unit distance change amount that is a change in the inter-unit distance when a state where the distance adjusting unit does not apply the opposing force against the biasing force and the recording sheet is not fed into a nip between the image carrier and the contact unit is shifted to a state where the recording sheet is passed through the nip without the distance adjusting unit applying the opposing force against the biasing force, wherein
the distance adjusting unit adjusts the inter-unit distance based on the inter-unit distance change amount detected by the distance-change detector to transfer a visible image formed on the surface of the image carrier onto the recording sheet passed through the nip.
8. The image forming apparatus according to claim 7, wherein the distance adjusting unit adjusts the inter-unit distance so that an inter-unit distance difference between a state where the distance adjusting unit does not apply the opposing force against the biasing force and the recording sheet is not fed into the nip and a state where the distance adjusting unit adjusts the inter-unit distance by applying the opposing force against the biasing force but the recording sheet is not fed into the nip is equal to or less than the inter-unit distance change amount.
9. The image forming apparatus according to claim 7, further comprising a thickness-information acquiring unit that acquires thickness information of the recording sheet, wherein
the distance adjusting unit includes a sheet conveying path provided in either one of an upstream side and a downstream side of a contact portion between the image carrier and the contact unit in a sheet conveying direction, the sheet conveying path being structured so that a force is applied to the either one of the image carrier and the contact unit to widen the inter-unit distance by stiffness of the recording sheet, and
the distance adjusting unit adjusts the inter-unit distance so that an inter-unit distance difference between a state where the distance adjusting unit does not apply the opposing force against the biasing force and the recording sheet is not fed into the nip and a state where the distance adjusting unit adjusts the inter-unit distance by applying the opposing force against the biasing force but the recording sheet not fed into the nip is equal to or more than a value indicated by the thickness information.
10. The image forming apparatus according to claim 9, further comprising:
a data storage unit; and
a storage control unit that stores the thickness information and the inter-unit distance change amount detected by the distance-change detector in the data storage unit in association with each other, wherein
the distance adjusting unit adjusts the inter-unit distance based on the thickness information and the inter-unit distance change amount stored in the data storage unit.
11. The image forming apparatus according to claim 10, wherein the storage control unit, when there occurs a difference between the inter-unit distance change amount stored in the data storage unit and the inter-unit distance change amount detected by the distance-change detector in the state where the recording sheet is passed through the nip without the distance adjusting unit applying the opposing force against the biasing force, changes the inter-unit distance change amount stored in the data storage unit based on the inter-unit distance change amount detected by the distance-change detector.
12. The image forming apparatus according to claim 7, wherein
the distance-change detector detects the inter-unit distance change amount while the recording sheet is passed through the nip without the distance adjusting unit applying the opposing force against the biasing force in a state where a visible image is not formed on the surface of the image carrier,
the distance adjusting unit adjusts the inter-unit distance based on the inter-unit distance change amount detected by the distance-change detector, and
the visible image formed on the image carrier is transferred onto another recording sheet by passing the another recording sheet through the nip formed after the distance adjusting unit adjusts the inter-unit distance.
13. The image forming apparatus according to claim 7, wherein when an image is continuously formed on a plurality of recording sheets having same thickness by passing the recording sheets through the nip, the distance-change detector detects the inter-unit distance change amount while the visible image is transferred onto a first recording sheet from the image carrier without the distance adjusting unit applying the opposing force against the biasing force, and
the distance adjusting unit adjusts the inter-unit distance based on the inter-unit distance change amount detected by the distance-change detector before second and subsequent recording sheets are fed into the nip.
14. The image forming apparatus according to claim 7, wherein the distance adjusting unit is configured so that the inter-unit distance is adjusted only when the inter-unit distance change amount is a predetermined value or more.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A consumer electronic device comprising:
a housing;
a user-actuated physical button exposed through an external surface of the housing;
a mechanical switch coupled to the physical button, the switch having a pair of terminals;
a first resistor being electrically coupled either in series or in parallel with the terminals of the switch;
a first spark gap coupled in parallel with the first resistor; and
a buffer circuit that is coupled to the switch, wherein the buffer circuit processes a signal that varies based on the switch being closed or open, and wherein the switch is closed when the user-actuated physical button is actuated and is open when the user-actuated physical button is not actuated.
2. The device of claim 1, further comprising:
a DC power supply, wherein the first resistor is coupled to the power supply either in series between the power supply and the switch, or in parallel with the switch.
3. The device of claim 1, wherein
the first resistor comprises a discrete surface mount resistor package soldered to a pair of pads in a top metal layer of a printed circuit board, and
the first spark gap includes a pair of conductive footprints patterned in the top metal layer and directly connected to the pair of pads in the top metal layer, respectively.
4. The device of claim 1, wherein the first spark gap passes signals having a high frequency and high voltage, and does not pass signals having a low frequency and low voltage.
5. The device of claim 4, wherein the signals having the high frequency and high voltage include an electrostatic discharge (ESD) strike and the signals having the low frequency and low voltage include signals from the switch.
6. The device of claim 1, wherein the first spark gap is directly connected to the first resistor.
7. The device of claim 2, wherein the first resistor is directly connected to at least one of the terminals of the switch.
8. The device of claim 1, wherein the buffer circuit further transmits the processed signal to a processor or a system on a chip (SOC) that detects whether the user-actuated physical button is actuated based on the processed signal.
9. A consumer electronic device comprising:
a housing;
a user-actuated physical button exposed through an external surface of the housing;
a mechanical switch coupled to the physical button, the switch having a pair of terminals;
a first resistor being electrically coupled either in series or in parallel with the terminals of the switch;
a first spark gap coupled in parallel with the first resistor;
a DC power supply, wherein the first resistor is coupled to the power supply either in series between the power supply and the switch, or in parallel with the switch;
a second resistor being electrically coupled in series between the terminals of the switch and ground, wherein the first resistor is coupled in series between the power supply and the switch; and
a second spark gap coupled in parallel with the second resistor.
10. A electronic circuit comprising
a mechanical switch coupled to a physical button, the switch having a pair of terminals;
a first resistor being electrically coupled either in series or in parallel with the terminals of the switch;
a first spark gap coupled in parallel with the first resistor; and
a buffer circuit that is coupled to the switch, wherein the buffer circuit processes a signal that varies based on the switch being closed or open.
11. The electronic circuit of claim 10, further comprising:
a DC power supply, wherein the first resistor is coupled to the power supply either in series between the power supply and the switch, or in parallel with the switch.
12. The electronic circuit of claim 10, wherein
the first resistor comprises a discrete surface mount resistor package soldered to a pair of pads in a top metal layer of a printed circuit board, and
the first spark gap includes a pair of conductive footprints patterned in the top metal layer and directly connected to the pair of pads in the top metal layer, respectively.
13. The electronic circuit of claim 10, wherein the first spark gap passes signals having a high frequency and high voltage, and does not pass signals having a low frequency and low voltage.
14. The electronic circuit of claim 13, wherein the signals having the high frequency and high voltage include an electrostatic discharge (ESD) strike and the signals having the low frequency and low voltage include signals from the switch.
15. The electronic circuit of claim 10, wherein the first spark gap is directly connected to the first resistor.
16. The electronic circuit of claim 11, wherein the first resistor is directly connected to at least one of the terminals of the switch.
17. The electronic circuit of claim 10, wherein the buffer circuit further transmits the processed signal to a processor or a system on a chip (SOC) that detects whether the switch is open or closed based on the processed signal.
18. An electronic circuit comprising:
a mechanical switch coupled to a physical button, the switch having a pair of terminals;
a first resistor being electrically coupled either in series or in parallel with the terminals of the switch;
a first spark gap coupled in parallel with the first resistor;
a DC power supply, wherein the first resistor is coupled to the power supply either in series between the power supply and the switch, or in parallel with the switch;
a second resistor being electrically coupled in series between the terminals of the switch and ground, wherein the first resistor is coupled in series between the power supply and the switch; and
a second spark gap coupled in parallel with the second resistor.