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US4817877A Expired / Lapsed US ⏱️ 0.0 years remaining

Shredding machine

Assignee: Sharp Corp
•
Filing: 1988-03-04
•
Granted: 1989-04-04
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Expires: 2008-03-04
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Abstract

Abstract A shredding machine includes a pair of juxtaposed cutting rollers for shredding paper material, a movable paper feed tray for supporting the paper material to be shredded on it, a paper feed tray drive motor capable of moving the paper feed tray between lowered and elevated positions, a paper feed mechanism and a control circuit for controlling the shredding operation. The paper feed mechanism comprises paper feed rollers for feeding the paper material from the paper feed tray towards the cutting rollers, a paper feed roller drive motor for driving the paper feed rollers and an actuator for detecting the position of the uppermost paper of a stack of papers placed on the paper feed tray. The operation of the paper feed mechanism is interrupted in the case where the actuator is not activated by the stack of papers over a predetermined period of time. Abnormal conditions of the drive motors can be detected by the control circuit on the basis of an electric voltage being supplied to each motor.

Inventors

  • 👤 Tetsuya Itoh
  • 👤 Shougo Iwai
  • 👤 Shizuo Yoshikawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 13:22
CPC Classifications
B; B02; B02C; B02C18/00; B02C18/0007; B02C18/06; B02C18/16; B02C18/22; B02C18/2225; B02C18/2283; B02C2018/0023; B02C2018/0038; B02C2018/0069

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 127 words
A shredding machine which comprises: a cutting means for shredding paper material; a paper feed tray movable between lowered and elevated positions and adapted to support thereon the paper material to be shredded; a feed means for feeding the paper material from said paper feed tray towards said cutting means; a paper material detecting means for detecting a topmost portion of the paper material placed on said paper feed tray; a paper feed tray driving means for moving said paper feed tray in response to a signal outputted from said paper material detecting means; and a control means for interrupting the operation of said feed means in the case where the signal outputted from said paper material detecting means remains unchanged over a predetermined length of time.
Claim 2
Dependent Claim 127 words
A shredding machine which comprises: a cutting means for shredding paper material; a paper feed tray movable between lowered and elevated positions and adapted to support thereon the paper material to be shredded; a feed means for feeding the paper material from said paper feed tray towards said cutting means; a paper material detecting means for detecting a topmost portion of the paper material placed on said paper feed tray; a paper feed tray driving means for moving said paper feed tray in response to a signal outputted from said paper material detecting means; and a control means for interrupting the operation of said feed means in the case where the signal outputted from said paper material detecting means remains unchanged over a predetermined length of time.
Claim 3
Dependent Claim 22 words
The machine as claimed in claim 1, wherein said paper material detecting means is provided in the vicinity of said feed means.
Claim 4
Dependent Claim 124 words
A shredding machine which comprises: a cutting means for shredding paper material; a paper feed tray movable between lowered and elevated positions and adapted to support thereon the paper material to be shredded; a feed means for feeding the paper material from said paper feed tray towards said cutting means; a first driving means for moving the paper material placed on said paper feed tray towards said feed means; a second driving means for driving said feed means; a comparing means for comparing an electric voltage supplied to said first and second driving means with a predetermined voltage; and a control means for controlling at least one of said first and second driving means in response to a signal outputted from said comparing means.
Claim 5
Dependent Claim 124 words
A shredding machine which comprises: a cutting means for shredding paper material; a paper feed tray movable between lowered and elevated positions and adapted to support thereon the paper material to be shredded; a feed means for feeding the paper material from said paper feed tray towards said cutting means; a first driving means for moving the paper material placed on said paper feed tray towards said feed means; a second driving means for driving said feed means; a comparing means for comparing an electric voltage supplied to said first and second driving means with a predetermined voltage; and a control means for controlling at least one of said first and second driving means in response to a signal outputted from said comparing means.

References Cited (Backward Citations)

DE2214800A1 Cited
US4192467A Cited
US4466604A Cited
US4444382A Cited
JPS6241133A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-04-03 1992-10-03 1993-04-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-04-03 1996-10-03 1997-04-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-04-03 2000-10-03 2001-04-04 $7700.00 Window Closed / Lapsed

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