1. A signal synchronizing system comprising:
comparison circuitry operable for comparing a synchronizing signal with an input signal to generate a comparison result; and
control circuitry coupled to said comparison circuitry and operable for adjusting said synchronizing signal into a range that is determined by said input signal, and operable for controlling said range according to said comparison result, wherein said range has a first width if said comparison result indicates that said synchronizing signal is outside said range, and wherein said range has a second width that is greater than said first width if said comparison result indicates that said synchronizing signal is within said range.
2. The signal synchronizing system as claimed in claim 1, wherein said comparison circuitry compares a synchronizing frequency of said synchronizing signal with an input frequency of said input signal to generate said comparison result.
3. The signal synchronizing system as claimed in claim 1, wherein said comparison circuitry comprises:
a switch controlled by said input signal;
a power source coupled to said switch and operable for generating a current according to said synchronizing signal to charge capacitive circuitry via said switch; and
a comparator coupled to said capacitive circuitry and operable for comparing a voltage on said capacitive circuitry with a boundary reference to generate said comparison result.
4. The signal synchronizing system as claimed in claim 3, wherein said power source also generates said current according to a preset reference that determines said boundary reference.
5. The signal synchronizing system as claimed in claim 3, wherein said control circuitry controls said range by controlling said boundary reference.
6. The signal synchronizing system as claimed in claim 1, wherein said control circuitry comprises counter circuitry to generate a control signal by accumulating said comparison result.
7. The signal synchronizing system as claimed in claim 6, further comprising:
oscillator circuitry coupled to said counter circuitry and operable for generating said synchronizing signal and adjusting a synchronizing frequency of said synchronizing signal according to said control signal.
8. The signal synchronizing system as claimed in claim 6, wherein said control signal increases a synchronizing frequency of said synchronizing signal if said synchronizing frequency is less than an input frequency of said input signal, and wherein said control signal decreases said synchronizing frequency if said synchronizing frequency is greater than said input frequency.
9. A method for synchronizing a signal, said method comprising:
comparing a synchronizing signal with an input signal to generate a comparison result;
adjusting said synchronizing signal into a range that is determined by said input signal;
controlling said range to have a first width if said comparison result indicates that said synchronizing signal is within said range; and
controlling said range to have a second width that is greater than said first width if said comparison result indicates that said synchronizing signal is outside said range.
10. The method as claimed in claim 9, wherein said comparing comprises:
comparing a synchronizing frequency of said synchronizing signal with an input frequency of said input signal to generate said comparison result.
11. The method as claimed in claim 9, wherein said comparing comprises:
controlling a switch using said input signal;
generating a current according to said synchronizing signal to charge capacitive circuitry via said switch; and
comparing a voltage on said capacitive circuitry with a boundary reference to generate said comparison result.
12. The method as claimed in claim 11, wherein said generating comprises:
generating said current also according to a preset reference that determines said boundary reference.
13. The method as claimed in claim 11, wherein said controlling said range comprises:
controlling said range by controlling said boundary reference.
14. The method as claimed in claim 9, wherein said controlling comprises:
generating a control signal by accumulating said comparison result.
15. The method as claimed in claim 14, wherein said controlling further comprises:
increasing a synchronizing frequency of said synchronizing signal using said control signal if said synchronizing frequency is less than an input frequency of said input signal; and
decreasing said synchronizing frequency using said control signal if said synchronizing frequency is greater than said input frequency.
16. A signal synchronizing system comprising:
control circuitry operable for adjusting a synchronizing signal into a range that is determined by an input signal, and operable for controlling said range according to a difference between said synchronizing signal and said input signal, wherein said range has a first width if said difference is greater than an offset, and wherein said range has a second width that is greater than said first width if said difference is less than said offset; and
signal generator circuitry coupled to said control circuitry and operable for generating said synchronizing signal according to said difference between said synchronizing signal and said input signal.
17. The signal synchronizing system as claimed in claim 16, wherein said signal generator circuitry increases a synchronizing frequency of said synchronizing signal if said difference is less than a first frequency offset, and wherein said signal generator circuitry decreases said synchronizing frequency if said difference is greater than a second frequency offset.
18. The signal synchronizing system as claimed in claim 16, further comprising:
a switch controlled by said input signal;
a power source coupled to said switch and operable for generating a current according to said synchronizing signal to charge capacitive circuitry via said switch; and
a comparator coupled to said capacitive circuitry and operable for comparing a voltage on said capacitive circuitry with a boundary reference to generate a comparison result.
19. The signal synchronizing system as claimed in claim 18, wherein said power source also generates said current according to a preset reference that determines said boundary reference.
20. The signal synchronizing system as claimed in claim 18, wherein said control circuitry controls said range by controlling said boundary reference.
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 sheet post-processing apparatus comprising:
discharge means for discharging a sheet,
sheet storage means established below the sheet discharge means for substantially supporting the sheet discharged from the discharge means,
sheet support means provided between the sheet storage means and the discharge means to form a step with respect to the sheet storage means, said sheet support means being disposed at a corner of a rear end and one side edge of the sheet storage means,
post-processing means for post-processing the sheet straddling the sheet support means and the sheet storage means,
moving means for moving the sheet postprocessed by the post-processing means in a direction different from a discharge direction by the discharge means to discharge a part of the sheet located on the sheet support means to the storage means, and
aligning means disposed at the sheet support means for aligning the sheet discharged on the sheet support means, said aligning means and said moving means moving the sheet in directions substantially opposite to each other, different from the discharge direction.
2. A sheet post-processing apparatus according to claim 1, wherein said aligning means aligns the sheet straddling the sheet support means and the sheet storage means prior to the post-processing using the post-processing means.
3. A sheet post-processing apparatus according to claim 2, wherein said moving means moves the sheet postprocessed by the post-processing means in a direction substantially perpendicular to the discharge direction by the discharge means to discharge the sheet to the storage means.
4. A sheet post-processing apparatus according to claim 2, wherein said sheet support means is a tray disposed at the corner above the sheet storage means.
5. A sheet post-processing apparatus according to claim 4, further comprising a positioning plate disposed on the tray for aligning a side portion of the sheet discharged from the discharge means, said aligning means being disposed on the tray for aligning the sheet discharged on the tray to the positioning plate.
6. A sheet post-processing apparatus according to claim 5, wherein said post processing means and said moving means are disposed on the tray.
7. A sheet post-processing apparatus according to claim 5, wherein said moving means is a lever rotationally attached to the tray for pushing the sheet on the tray to the sheet storage means, and a cam for moving the lever.
8. A sheet post-processing apparatus according to claim 1, wherein said moving means moves the sheet post-processed by the post-processing means in a direction substantially perpendicular to the discharge direction by the discharge means to discharge the sheet to the storage means.
9. A sheet post-processing apparatus according to claim 1, wherein the moving means acts on a curled portion of the sheet post-processed by the post-processing means and discharges the sheet to the storage means.
10. An image forming apparatus comprising: sheet feeding means for feeding a sheet one at a time, image forming means for forming a desired image on the sheet fed by the sheet feeding means, and the sheet post-processing apparatus according to claim 1 for post-processing the sheet with the image formed thereupon by the image forming means.
11. A sheet post-processing apparatus according to claim 1, wherein said moving means is a lever rotationally disposed at one side of the sheet support means, said lever being moved to push the sheet on the sheet support means to entirely locate the sheet on the sheet storage means.
12. A sheet post-processing apparatus according to claim 11, wherein said lever pushes the sheet on the sheet support means in a direction substantially perpendicularly to the sheet discharge direction.
13. A sheet post-processing apparatus according to claim 1, wherein said aligning means is a belt unit disposed above the sheet support means, said belt unit moving the sheet on the sheet support means to one side thereof.
14. A sheet post-processing apparatus comprising:
discharge means for discharging a sheet,
sheet storage means established below the sheet discharge means for substantially supporting the sheet discharged from the discharge means,
sheet support means provided between the sheet storage means and the discharge means to form a step with respect to the sheet storage means, said sheet support means being disposed at a corner of a rear end and one side edge of the sheet storage means,
post-processing means for post-processing the sheet straddling the sheet support means and the sheet storage means,
moving means for moving the sheet post-processed by the post-processing means in a direction different from a discharge direction by the discharge means to discharge a part of the sheet located on the sheet support means to the storage means,
aligning means disposed at the sheet support means for aligning the sheet discharged on the sheet support means, said aligning means and said moving means moving the sheet in directions opposite to each other, different from the discharge direction, and
drive means disposed between the sheet support means and the sheet storage means for driving the sheet moving means.