1. An image forming apparatus comprising:
a belt unit includes a belt, a plurality of rollers supporting the belt, and a frame rotatably supporting the rollers; and
an apparatus main body in which the belt unit is detachably mounted;
wherein the belt unit comprises:
a securing member disposed at an inner surface side of the belt and configured to impart a tensile force to the belt when the belt unit is detached from the apparatus main body.
2. The image forming apparatus according to claim 1, wherein the apparatus main body comprises:
a tension imparting device that imparts an operating tensile force to the belt of the belt unit in a mounted state.
3. The image forming apparatus according to claim 2, wherein the belt unit comprises:
an urging device that imparts the tensile force to the belt by generating an urge that applies an outward force to the securing member in a state in which the belt unit is detached from the apparatus main body.
4. The image forming apparatus according to claim 3, wherein the tensile force imparted to the belt by the urging device is less than the operating tensile force that is imparted to the belt by the tension imparting device.
5. The image forming apparatus according to claim 3, wherein the apparatus main body comprises:
an urge releasing device that releases the urge generated by the urging device in a state in which the belt unit is mounted in the apparatus main body.
6. The image forming apparatus according to claim 5, wherein the urge releasing device releases the urge generated by the urging device occurring with an operation to mount the belt unit in the apparatus main body.
7. The image forming apparatus according to claim 1, wherein the belt unit comprises:
a fixing device configured to fix the securing member in an outwardly projecting position in a state in which the belt unit is detached from the apparatus main body.
8. The image forming apparatus according to claim 7, wherein the apparatus main body comprises:
a fixation releasing device that releases the fixation of the fixing device in a state in which the belt unit is mounted in the apparatus main body.
9. The image forming apparatus according to claim 8, wherein the fixation releasing device releases the fixation by the fixing device occurring with an operation to mount the belt unit in the apparatus main body.
10. The image forming apparatus according to claim 2, wherein the securing member comprises:
a tension roller that imparts the operating tensile force to the belt via the tension imparting device in a state in which the belt unit is mounted in the apparatus main body.
11. The image forming apparatus according to claim 2, wherein the securing member comprises:
a transfer roller that is disposed opposite an image bearing device provided in the apparatus main body such that the belt is positioned between the transfer roller and the image bearing device; and
wherein the transfer roller transfers a developer image that is carried on the image bearing device via application of a transfer bias between the image bearing device and the transfer roller.
12. The image forming apparatus according to claim 2, wherein the apparatus main body comprises:
a cleaning roller that contacts against an outer surface of the belt; and
wherein the securing member comprises a cleaner backup roller that is disposed opposite to the cleaning roller to position the belt between the cleaner backup roller and the cleaning roller.
13. The image forming apparatus according to claim 1, wherein the belt comprises:
a protruding guide rib on an inner surface that engages with the rollers to inhibit skewing of the belt.
14. An image forming apparatus including a belt unit detachably mounted to an apparatus main body and comprising a belt, a plurality of rollers supporting the belt in a stretched state, and a frame rotatably supporting the rollers, and also including a tension imparting device that imparts an operating tensile force to the belt of the belt unit in a mounted state, wherein the belt unit comprises:
a plurality of securing members located along an inner surface side of the belt that impart a tensile force to the belt when the belt unit is detached from the apparatus main body.
15. The image forming device of claim 14 wherein each of the plurality of securing members comprises a transfer roller positioned opposite to a photosensitive drum of one of a corresponding plurality of development cartridges via the belt when the belt unit and the plurality of development cartridges are in a mounted condition.
16. The image forming device of claim 14 wherein each of the plurality of securing members imparts the tensile force to the belt via a corresponding plurality of urging devices;
wherein the image forming device comprises an operation part that engages said each of the plurality of urging devices when the belt unit is mounted to the image forming device; and
wherein the operation device is actuated to release the tensile force generated by the plurality of urging devices.
17. The image forming device of claim 16, wherein each of the plurality of urging devices comprises a first resilient member and a second resilient member;
wherein each of the second resilient members generate a contact force;
wherein the first resilient members and the second resilient members generate the tensile force; and
wherein the contact force presses the belt between each of the transfer rollers and a photosensitive drum of each of a corresponding plurality of development cartridges.
18. An image forming device comprising a belt unit detachably mounted in an apparatus main body and including a belt, a plurality of rollers supporting the belt in a stretched state, and a frame rotatably supporting the rollers, wherein the belt unit comprises:
a securing member disposed at an inner surface side of the belt and configured to impart a tensile force to the belt when the belt unit is detached from the apparatus main body;
wherein the image forming device includes a tension imparting device that imparts an operating tensile force to the belt of the belt unit when the belt unit is attached to the apparatus main body;
wherein the securing member is a backup roller that imparts the tensile force via a change of position in a tension inducing direction with respect to the belt due to an urging of an urging device.
19. The image forming device according to claim 18 comprising an urge releasing device that releases the tensile force when the belt unit is attached to the apparatus main body.
20. The image forming apparatus according to claim 19, wherein the belt comprises:
a protruding guide rib on an inner surface that engage with the rollers to guide the belt.
The claims below are in addition to those above.
All refrences to claims which appear below refer to the numbering after this setence.
1. A flash memory, comprising:
at least one floating-gate memory cell comprising a source, a drain, a control gate, a floating gate and a substrate;
a memory control circuit for controlling operations on the at least one floating-gate memory cell;
a wordline coupled to the control gate of the at least one memory cell; and
a wordline drive transistor coupled to the wordline;
wherein the memory control circuit is adapted to supply a positive voltage pulse to the source relative to a common voltage while supplying a negative voltage pulse to the control gate relative to the common voltage;
wherein the memory control circuit is further adapted to discharge the positive voltage pulse while continuing to supply the negative voltage pulse; and
wherein the memory control circuit is further adapted to discharge the negative voltage pulse before re-supplying a positive voltage pulse to the source relative to the common voltage.
2. The flash memory of claim 1, wherein the memory control circuit is further adapted to supply the negative voltage pulse for at least 1 ms after beginning to discharge the positive voltage pulse.
3. The flash memory of claim 1, wherein the positive voltage is discharged at a rate sufficient to couple a second negative voltage to the floating gate.
4. The flash memory of claim 3, wherein the rate sufficient to couple a second negative voltage to the floating gate is a rate sufficient to discharge the positive voltage in less than 1 ms.
5. The flash memory of claim 3, wherein the magnitude of the second negative voltage is greater than 3 volts.
6. The flash memory of claim 5, wherein the positive voltage applied between the source and an area of common voltage is between 3 and 6 V.
7. The flash memory of claim 1, wherein the wordline drive transistor has a low parasitic drain capacitance compared with a capacitance of the wordline.
8. The flash memory of claim 7, wherein the low parasitic drain capacitance is achieved, at least in part, by LDD regions.
9. The flash memory of claim 7, wherein the low parasitic drain capacitance is achieved, at least in part, by gate spacers.
10. The flash memory of claim 7, wherein the low parasitic drain capacitance is on the order of 1-10 fF.
11. A flash memory, comprising:
at least one floating-gate memory cell comprising a source, a drain, a control gate, a floating gate and a substrate;
a memory control circuit for controlling operations on the at least one floating-gate memory cell;
a wordline coupled to the control gate of the at least one memory cell; and
a wordline drive transistor coupled to the wordline and having a parasitic drain capacitance on the order of 1-10 fF;
wherein the memory control circuit is adapted to supply a positive voltage pulse to the source relative to a common voltage while supplying a negative voltage pulse to the control gate relative to the common voltage;
wherein the memory control circuit is further adapted to discharge the positive voltage pulse while continuing to supply the negative voltage pulse;
wherein the memory control circuit is further adapted to discharge the positive voltage pulse at a rate sufficient to couple a second negative voltage to the floating gate; and
wherein the memory control circuit is further adapted to discharge the negative voltage pulse before re-supplying a positive voltage pulse to the source relative to the common voltage.
12. The flash memory of claim 11, wherein the memory control circuit is further adapted to supply the negative voltage pulse for at least 1 ms after beginning to discharge the positive voltage pulse.
13. The flash memory of claim 11, wherein the rate sufficient to couple a second negative voltage to the floating gate is a rate sufficient to discharge the positive voltage in less than 1 ms.
14. The flash memory of claim 11, wherein the magnitude of the second negative voltage is greater than 3 volts.
15. The flash memory of claim 14, wherein the positive voltage applied between the source and an area of common voltage is between 3 and 6 V.
16. A flash memory, comprising:
at least one floating-gate memory cell comprising a source, a drain, a control gate, a floating gate and a substrate;
a memory control circuit for controlling operations on the at least one floating-gate memory cell;
a wordline coupled to the control gate of the at least one memory cell; and
a wordline drive transistor coupled to the wordline and having a parasitic drain capacitance on the order of 1-10 fF;
wherein the memory control circuit is adapted to supply a positive voltage pulse to the source relative to a common voltage while supplying a negative voltage pulse to the control gate relative to the common voltage;
wherein the memory control circuit is further adapted to discharge the positive voltage pulse while continuing to supply the negative voltage pulse;
wherein the memory control circuit is further adapted to discharge the negative voltage pulse before re-supplying a positive voltage pulse to the source relative to the common voltage; and
wherein the memory control circuit is further adapted to supply the negative voltage pulse for at least 1 ms after beginning to discharge the positive voltage pulse.
17. The flash memory of claim 16, wherein the positive voltage is discharged at a rate sufficient to couple a second negative voltage to the floating gate.
18. The flash memory of claim 17, wherein the rate sufficient to couple a second negative voltage to the floating gate is a rate sufficient to discharge the positive voltage in less than 1 ms.
19. The flash memory of claim 17, wherein the magnitude of the second negative voltage is greater than 3 volts.
20. The flash memory of claim 19, wherein the positive voltage applied between the source and an area of common voltage is between 3 and 6 V.