US4452400A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rotary shredding apparatus
Assignee: Williams Patent Crusher and Pulverizer Co Inc
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Filing: 1983-09-12
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Granted: 1984-06-05
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Expires: 2003-09-12
Abstract
Abstract Rotary shredding apparatus for processing materials of various sorts in which the hydraulic drive for the counterrotating cutter shafts comprises a reversible hydraulic motor supplied with pressure fluid under the directional control of a fluid flow reversing valve. The flow reversing valve is controlled by a zero speed responsive device for sensing jam conditions that could stop cutter shaft rotation, thereby placing the valve in a control system which is independent of the pressure conditions in the fluid pressure system so that the hydraulic motor will continue to be supplied with pressure fluid up to the limit set by the usual pressure relief means.
Inventors
- 👤 Robert M. Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:14
CPC Classifications
B; B02; B02C; B02C18/00; B02C18/06; B02C18/16; B02C18/24; B02C2018/164
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
306 words
Rotary shredding apparatus in which counterrotating shafts carry cooperating cutter elements for shredding material, the shredding apparatus comprising: (a) counterrotating shafts and a reversible hydraulic motor operably connected to the counterrotating shafts for driving the same in a forward shredding motion and in a reverse direction; (b) hydraulic fluid flow circuit means connected to said reversible motor and including a pump to supply fluid under pressure through said fluid flow circuit means; (c) a pressure relief valve in said hydraulic fluid circuit means for imposing a predetermined upper limit on the pressure existing in said circuit means between said pump and reversible motor; (d) motion responsive means in the shredding apparatus for generating signals continuously during the continuance of a forward shredding drive motion of the counterrotating shafts; (e) hydraulic fluid flow directing valve means connected into said hydraulic fluid flow circuit means to direct the flow of hydraulic fluid at the predetermined pressure limit permitted by said pressure relief valve to said reversible hydraulic motor for determining the direction of drive for the counterrotating shafts; and (f) control means connected to said motion responsive means and said hydraulic fluid flow directing valve, said control means being operative in response to the continuous generation of signals by said motion responsive means for operating said hydraulic fluid flow directing valve to direct the pressure fluid at the predetermined upper limit in a direction for effecting the drive of said reversible hydraulic motor in a forward shredding motion direction, said control means being responsive to the cessation of signals by said motion responsive means for operating said hydraulic fluid flow directing valve to direct the pressure fluid at the predetermined upper limit in a direction for effecting the drive of said reversible hydraulic motor in a reverse direction for a predetermined time prior to returning to forward shredding.
Claim 2
Dependent Claim
306 words
Rotary shredding apparatus in which counterrotating shafts carry cooperating cutter elements for shredding material, the shredding apparatus comprising: (a) counterrotating shafts and a reversible hydraulic motor operably connected to the counterrotating shafts for driving the same in a forward shredding motion and in a reverse direction; (b) hydraulic fluid flow circuit means connected to said reversible motor and including a pump to supply fluid under pressure through said fluid flow circuit means; (c) a pressure relief valve in said hydraulic fluid circuit means for imposing a predetermined upper limit on the pressure existing in said circuit means between said pump and reversible motor; (d) motion responsive means in the shredding apparatus for generating signals continuously during the continuance of a forward shredding drive motion of the counterrotating shafts; (e) hydraulic fluid flow directing valve means connected into said hydraulic fluid flow circuit means to direct the flow of hydraulic fluid at the predetermined pressure limit permitted by said pressure relief valve to said reversible hydraulic motor for determining the direction of drive for the counterrotating shafts; and (f) control means connected to said motion responsive means and said hydraulic fluid flow directing valve, said control means being operative in response to the continuous generation of signals by said motion responsive means for operating said hydraulic fluid flow directing valve to direct the pressure fluid at the predetermined upper limit in a direction for effecting the drive of said reversible hydraulic motor in a forward shredding motion direction, said control means being responsive to the cessation of signals by said motion responsive means for operating said hydraulic fluid flow directing valve to direct the pressure fluid at the predetermined upper limit in a direction for effecting the drive of said reversible hydraulic motor in a reverse direction for a predetermined time prior to returning to forward shredding.
Claim 3
Dependent Claim
47 words
The rotary shredding apparatus according to claim 1 wherein the reversible hydraulic motor is operably connected to the counterrotating shafts through a train of gears, and said motion responsive means is positioned adjacent said train of gears for generating signals during operation of said train of gears.
Claim 4
Dependent Claim
109 words
The rotary shredding apparatus according to claim 1 wherein said control means includes a counterrotating shaft jam sensor circuit responsive upon cessation of signals from said motion responsive means for sequencing said hydraulic fluid flow directing means to change said reversible hydraulic motor drive between a forward direction and reverse direction and timing the duration thereof, said sequencing from the forward to the reverse direction being delayed to allow the pressure fluid supply to said reversible hydraulic motor to continue driving the counterrotating shafts for a predetermined period of time in advance of initiating the sequencing of said hydraulic fluid flow control means to reverse said reversible hydraulic motor.
Claim 5
Dependent Claim
68 words
The rotary shredding apparatus according to claim 1 wherein a plurality of cooperating circuits are arranged in said control means so as to be responsive to the reception from said motion responsive means of signals and the cessation of signals by said motion responsive means for determining the timing for the operation of said hydraulic fluid flow directing valve from the first mentioned to the second mentioned operation.
Claim 6
Dependent Claim
55 words
The rotary shredding apparatus according to claim 1 wherein the first position of said hydraulic fluid flow directing valve supplies hydraulic pressure fluid to said hydraulic motor for operating said reversible hydraulic motor in a forward shredding direction so as to generate maximum torque within the hydraulic pressure limits permitted by said safety relief valve.
Claim 7
Dependent Claim
38 words
The rotary shredding apparatus according to claim 1 wherein said control means consists in a programmable computer, and said motion responsive means for generating signals is independent of influence from the pressure in said hydraulic fluid flow circuit.
Claim 8
Dependent Claim
303 words
Rotary shredding apparatus in which counterrotating shafts carry cooperating cutter elements for shredding material, the shredding apparatus comprising: (a) counterrotating shafts and a reversible hydraulic motor operably connected to the counterrotating shafts for driving the same in a forward shredding motion and in a reverse direction; (b) hydraulic fluid flow circuit means connected to said reversible motor and including a pump to supply fluid under pressure through said fluid flow circuit means; (c) a pressure relief valve in said hydraulic fluid circuit means for imposing a predetermined upper limit on the pressure existing in said circuit means between said pump and reversible motor; (d) means in the shredding apparatus for generating signals responsive to speed of the drive of the counterrotating shafts by said reversible hydraulic motor; (e) hydraulic fluid flow directing valve means connected into said hydraulic fluid flow circuit means to direct the flow of hydraulic fluid at the predetermined pressure limit permitted by said pressure relief valve to said reversible hydraulic motor for determining the direction of drive for the counterrotating shafts; and (f) control means connected to said speed responsive means and to said hydraulic fluid flow directing valve, said control means being operative in response to the generation of signals by said speed responsive means for operating said hydraulic fluid flow directing valve to direct the pressure fluid in said hydraulic fluid flow circuit means for affecting the direction of rotation of said reversible hydraulic motor, and said control means being responsive to the cessation of signals from said speed responsive means for changing the direction of rotation of said hydraulic motor and such that for changing the direction of rotation of said hydraulic motor and such that for changing the direction reverse to the forward shredding direction the reverse rotation continues for a limited predetermined time period.
Claim 9
Dependent Claim
303 words
Rotary shredding apparatus in which counterrotating shafts carry cooperating cutter elements for shredding material, the shredding apparatus comprising: (a) counterrotating shafts and a reversible hydraulic motor operably connected to the counterrotating shafts for driving the same in a forward shredding motion and in a reverse direction; (b) hydraulic fluid flow circuit means connected to said reversible motor and including a pump to supply fluid under pressure through said fluid flow circuit means; (c) a pressure relief valve in said hydraulic fluid circuit means for imposing a predetermined upper limit on the pressure existing in said circuit means between said pump and reversible motor; (d) means in the shredding apparatus for generating signals responsive to speed of the drive of the counterrotating shafts by said reversible hydraulic motor; (e) hydraulic fluid flow directing valve means connected into said hydraulic fluid flow circuit means to direct the flow of hydraulic fluid at the predetermined pressure limit permitted by said pressure relief valve to said reversible hydraulic motor for determining the direction of drive for the counterrotating shafts; and (f) control means connected to said speed responsive means and to said hydraulic fluid flow directing valve, said control means being operative in response to the generation of signals by said speed responsive means for operating said hydraulic fluid flow directing valve to direct the pressure fluid in said hydraulic fluid flow circuit means for affecting the direction of rotation of said reversible hydraulic motor, and said control means being responsive to the cessation of signals from said speed responsive means for changing the direction of rotation of said hydraulic motor and such that for changing the direction of rotation of said hydraulic motor and such that for changing the direction reverse to the forward shredding direction the reverse rotation continues for a limited predetermined time period.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-06-05 | 1987-12-05 | 1988-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-06-05 | 1991-12-05 | 1992-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-06-05 | 1995-12-05 | 1996-06-05 | $7700.00 | Window Closed / Lapsed |