US3925713A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatically guiding workpieces through a machine
Assignee: Shoe and Allied Trades Research Association
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Filing: 1973-11-07
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Granted: 1975-12-09
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Expires: 1993-11-07
Abstract
Abstract Automatic guiding apparatus has first and second drive wheels which are driven from a common source for effecting feeding of a workpiece in a straight line through a machine. For effecting steering of the workpiece along a line parallel to the edge, a sensor senses the edge, a computer calculates the speed differential required to be imparted to the two drive wheels for steering about the centre of curvature of the edge, and an adding device superimposes additional positive or negative speed on one of the drive wheels. The adding device can be mechanical, such as a differential gearbox, where the wheels are driven from a common motor, or a frequency shifter where the wheels are driven by separate stepper motors supplied with pulses from a common oscillator. Automatic speed control is incorporated for negotiating sharp corners. The drive wheels are parallel to each other. In an alternative embodiment, a pair of drive wheels feed the material through the machine with one edge in engagement with a stop and an auxiliary wheel, controlled by a servo and edge sensor, is driven in opposite directions transverse to the direction of feed for effecting steering.
Inventors
- 👤 Richard Malcolm Richmond
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:14
CPC Classifications
D; D05; D05B; D05B35/00; D05B35/10; D05B35/102; B; B23; B23Q; B23Q35/00; B23Q35/04; B23Q35/08; B23Q35/12; B23Q35/14; D05B73/00; D05B73/04; D05B73/12; D05D; D05D2207/00; D05D2207/02; D05D2207/04; D05D2207/05; D05D2207/06
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
106 words
Apparatus for guiding a workpiece through a machine to present to a work station successive portions of the workpiece located along a curved path, comprising drive means for imparting motion to the workpiece to advance said portions of said workpiece through said work station in a substantially constant direction, means for providing a signal dependent upon the radius of curvature of said curved path to be followed by the workpiece, and control means responsive to said signal for contRolling said drive means to cause the workpiece to rotate the workpiece so as to steer the workpiece substantially about the center of curvature of said curved path.
Claim 2
Dependent Claim
106 words
Apparatus for guiding a workpiece through a machine to present to a work station successive portions of the workpiece located along a curved path, comprising drive means for imparting motion to the workpiece to advance said portions of said workpiece through said work station in a substantially constant direction, means for providing a signal dependent upon the radius of curvature of said curved path to be followed by the workpiece, and control means responsive to said signal for contRolling said drive means to cause the workpiece to rotate the workpiece so as to steer the workpiece substantially about the center of curvature of said curved path.
Claim 3
Dependent Claim
53 words
Apparatus according to claim 1, wherein said drive means comprises first and second drive members adapted to engage the workpiece at spaced positions, and said control means is operative to cause said first and second drive members to be driven at speeds appropriate for effecting said steering about substantially said centre of curvature.
Claim 4
Dependent Claim
46 words
Apparatus according to claim 1, wherein said signal providing means comprises a sensor operable to sense a predetermined line on the workpiece and to generate said signal such as to cause said control means to drive said drive means such that said predetermined line is followed.
Claim 5
Dependent Claim
32 words
Apparatus according to claim 1, wherein said drive means comprises at least one drive member disposed immediately adjacent said work station and arranged to frictionally engage said workpiece to impart motion thereto.
Claim 6
Dependent Claim
126 words
Apparatus for guiding a workpiece through a machine, comprising drive means for imparting motion to the workpiece, means for providing a signal dependent upon the radius of curvature of a curved path to be followed by the workpiece, control means responsive to said signal for controlling said drive means to cause the workpiece to be steered substantially about the center of curvature of said curved path, said drive means comprising first and second drive members adapted to engage the workpiece at spaced positions, said control means being operative to cause said first and second drive means to be driven at speeds appropriate for effecting said steering about substantially said center of curvature, said drive members are operative to impart motion to said workpiece in parallel directions.
Claim 7
Dependent Claim
126 words
Apparatus for guiding a workpiece through a machine, comprising drive means for imparting motion to the workpiece, means for providing a signal dependent upon the radius of curvature of a curved path to be followed by the workpiece, control means responsive to said signal for controlling said drive means to cause the workpiece to be steered substantially about the center of curvature of said curved path, said drive means comprising first and second drive members adapted to engage the workpiece at spaced positions, said control means being operative to cause said first and second drive means to be driven at speeds appropriate for effecting said steering about substantially said center of curvature, said drive members are operative to impart motion to said workpiece in parallel directions.
Claim 8
Dependent Claim
75 words
Apparatus according to claim 5, wherein said drive means comprises common means operable for driving said drive members at speeds for effecting feeding of the workpiece along a substantially straight line and means interposed between said common drive means and at least one of said drive members for superimposing an additional positive or negative speed on said at least one member in response to said signal produced by said control means to effect said steering.
Claim 9
Dependent Claim
20 words
Apparatus according to claim 6, wherein said common means comprises a motor, and said interposed means comprises a transmission device.
Claim 10
Dependent Claim
82 words
Apparatus according to claim 7, wherein said transmission device comprises a differential gear mechanism having first and second inputs, a first of said inputs being connected to said motor to be driven thereby; and including a servo motor responsive to the signal produced by said control means for rotation in opposite directions, said servo motor being connected to the second said input of said differential gear mechanism, said differential gear mechanism having an output connected to said at least one drive member.
Claim 11
Dependent Claim
34 words
Apparatus according to claim 6, including first and second electric motors for driving said respective drive members, and wherein said common means comprises a power supply circuit for supplying electric power to said motors.
Claim 12
Dependent Claim
19 words
Apparatus according to claim 9, wherein said interposed means is between said power supply circuit and a said motor.
Claim 13
Dependent Claim
44 words
Apparatus according to claim 10, wherein said motors are stepper motors, said power supply circuit comprises an oscillator for producing pulses for supply to said stepper motors, and said interposed means comprises frequency shifting means responsive to the signal produced by said control means.
Claim 14
Dependent Claim
28 words
Apparatus according to claim 6, wherein said common means is operable at a variable speed for varying the speed at which the workpiece is fed through the machine.
Claim 15
Dependent Claim
30 words
Apparatus according to claim 12, including means for automatically varying the speed of said common means in dependence upon the magnitude of the signal provided by said signal generating means.
Claim 16
Dependent Claim
24 words
Apparatus according to claim 13, including a variable speed operating mechanism of said machine, said common means also providing drive to said operating mechanism.
Claim 17
Dependent Claim
18 words
Apparatus according to claim 6, wherein said common means is operable to drive said members intermittently and simultaneously.
Claim 18
Dependent Claim
45 words
Apparatus according to claim 15, wherein said control means receives a signal from said common means such that, in the periods between which intermittent drive is applied to said drive members, the speed to be superimposed on said at least one drive member is zero.
Claim 19
Dependent Claim
46 words
Apparatus according to claim 5, wherein said signal providing means comprises a sensor operable to sense a predetermined line on the workpiece and to generate said signal such as to cause said control means to drive said drive members such that said predetermined line is followed.
Claim 20
Dependent Claim
91 words
Apparatus according to claim 5, wherein said control means includes computing means, means to supply said signal to said computing means, and means to supply to said computing means a further signal representative of the speed of feeding the workpiece through the machine, said computing means being operable to effect a computation on said signals and to produce an output signal which is representative of the required angular velocity to be imparted to the workpiece to effect said steering correctly, and means for supplying said output signal to said drive means.
Claim 21
Dependent Claim
38 words
Apparatus according to claim 18, wherein said drive members are operable to impart motion to said workpiece in parallel directions, and wherein said output signal thereby represents the required speed difference to be imparted to said drive members.
Claim 22
Dependent Claim
31 words
Apparatus according to claim 19, wherein said drive members are disposed on a common line upon which the centres of curvature about which the workpiece can be steered are also located.
Claim 23
Dependent Claim
83 words
Apparatus according to claim 20, wherein said signal providing means comprises a sensor to sense a physical line on said workpiece, said sensor being located in advance of said common line and being adapted to produce a signal representative of the magnitude and direction of deviation of said physical line from a straight line normal to said common line and intersecting the point of intersection of said common line and said physical line, and said computing means being operative to compute the equation:
Claim 24
Dependent Claim
18 words
Apparatus according to claim 21, wherein said control means is operable to compute an approximation of said equation.
Claim 25
Dependent Claim
11 words
Apparatus according to claim 22, wherein said approximation comprises ignoring q2.
Claim 26
Dependent Claim
17 words
Apparatus according to claim 20, wherein said machine includes a work station disposed on said common line.
Claim 27
Dependent Claim
91 words
Apparatus for guiding a workpiece through a machine to present to a work station successive portions of said workpiece located along a curved path, comprising drive means operable for advancing said workpiece intermittently through the machine such that said successive portions of said workpiece move through said work station in a substantially constant direction, and control means for rotating said workpiece simultaneously with said intermittent advances thereof to effect steering of the workpiece along said path during said intermittent advances of said portions of said workpiecE in said substantially constant direction.
Claim 28
Dependent Claim
91 words
Apparatus for guiding a workpiece through a machine to present to a work station successive portions of said workpiece located along a curved path, comprising drive means operable for advancing said workpiece intermittently through the machine such that said successive portions of said workpiece move through said work station in a substantially constant direction, and control means for rotating said workpiece simultaneously with said intermittent advances thereof to effect steering of the workpiece along said path during said intermittent advances of said portions of said workpiecE in said substantially constant direction.
Claim 29
Dependent Claim
46 words
Apparatus according to claim 25, wherein said signal providing means comprises a sensor operable to sense a predetermined line on the workpiece and to generate said signal such as to cause said control means to drive said drive means such that said predetermined line is followed.
Claim 30
Dependent Claim
32 words
Apparatus according to claim 25, wherein said drive means comprises at least one drive member disposed immediately adjacent said work station and arranged to frictionally engage said workpiece to impart motion thereto.
Claim 31
Dependent Claim
91 words
Apparatus for guiding a workpiece through a machine to present to a work station successive portions of said workpiece located along a curved path, comprising a plurality of drive members engageable with the workpiece at spaced apart positions for imparting motion thereto, common means for driving said drive members at speeds for effecting feeding of the workpiece substantially in a straight line of constant direction, and means for superimposing additional speed on at least one of said drive members to cause the workpiece to rotate for effecting steering of the workpiece.
Claim 32
Dependent Claim
91 words
Apparatus for guiding a workpiece through a machine to present to a work station successive portions of said workpiece located along a curved path, comprising a plurality of drive members engageable with the workpiece at spaced apart positions for imparting motion thereto, common means for driving said drive members at speeds for effecting feeding of the workpiece substantially in a straight line of constant direction, and means for superimposing additional speed on at least one of said drive members to cause the workpiece to rotate for effecting steering of the workpiece.
Claim 33
Dependent Claim
46 words
Apparatus according to claim 28, wherein said signal providing means comprises a sensor operable to sense a predetermined line on the workpiece and to generate said signal such as to cause said control means to drive said drive means such that said predetermined line is followed.
Claim 34
Dependent Claim
16 words
Apparatus according to claim 28, wherein said drive members are disposed closely adjacent said work station.
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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) | 1978-12-08 | 1979-06-09 | 1979-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-08 | 1983-06-09 | 1983-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-08 | 1987-06-09 | 1987-12-09 | $7700.00 | Window Closed / Lapsed |