US3874205A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Digitally controlled multiple depth stop and return stroke limit control for press brakes
Assignee: Hurco Manufacturing Co Inc
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Filing: 1974-02-19
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Granted: 1975-04-01
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Expires: 1994-02-19
Abstract
Abstract A hydraulically driven press brake has an automatically positioned back gauge capable of changing workpiece gauging location after each bend. Variable ram closing stroke depth and variable ram return (opening) stroke length, is manually preprogrammable digitally by dial-in switches, and automatically coordinated with the gauge to provide the desired ram stroke depth for each bend in the workpiece and an appropriate subsequent length of ram return stroke. A rotary encoder monitors travel of the ram and supplies information to the control for the necessary positioning and coordination. Zero referencing is provided for the ram at closed condition, so all ram positions are designated by positive readings.
Inventors
- 👤 Gerald V Roch
- 👤 Edward H Sonn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:17
CPC Classifications
B; B21; B21D; B21D5/00; B21D5/006; B21D5/02; B30; B30B; B30B15/00; B30B15/16; B30B15/18; B30B15/26; G; G05; G05B; G05B19/00; G05B19/02; G05B19/18; G05B19/19; G05B19/21; G05B19/23; G05B19/238; G05B19/4093; Y; Y02; Y02P; Y02P90/00; Y02P90/02
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
210 words
Apparatus for controlling the ram of a hydraulic press brake during the procedure of making a series of bends in a workpiece; said apparatus comprising: manually operable establishing means for establishing a program for variably limiting the travel of a ram of a press brake, said establishing means being arranged in a plurality of stations separately assignable to workpiece bends having different parameters, said establishing means including a first set of mAnually operated switches for ram closing control and a second set of manually operated switches for ram opening control; first and second signal outputs, said first output being for a ram closing limit signal and the second output being for a ram opening limit signal; ram position indicating signal generating means having an output; and signal comparing means having inputs coupled to said gnerating means and to said switches for detecting a match between signals from said generating means and signals from said switches during opening and closing movement indicating signals from said signal generating means, to generate a ram stop signal at said first output when a match is made during indication of ram closing movement, and to generate a ram stop signal at said second output when a match is made during indication of ram opening movement.
Claim 2
Dependent Claim
210 words
Apparatus for controlling the ram of a hydraulic press brake during the procedure of making a series of bends in a workpiece; said apparatus comprising: manually operable establishing means for establishing a program for variably limiting the travel of a ram of a press brake, said establishing means being arranged in a plurality of stations separately assignable to workpiece bends having different parameters, said establishing means including a first set of mAnually operated switches for ram closing control and a second set of manually operated switches for ram opening control; first and second signal outputs, said first output being for a ram closing limit signal and the second output being for a ram opening limit signal; ram position indicating signal generating means having an output; and signal comparing means having inputs coupled to said gnerating means and to said switches for detecting a match between signals from said generating means and signals from said switches during opening and closing movement indicating signals from said signal generating means, to generate a ram stop signal at said first output when a match is made during indication of ram closing movement, and to generate a ram stop signal at said second output when a match is made during indication of ram opening movement.
Claim 3
Dependent Claim
160 words
The controller of claim 1 wherein: said first set of switches is arranged in a first plurality of groups of switches, one group for each of said stations, a different group of said plurality being provided for control of the ram during the making of each bend having ram operating requirement parameters different from those of the next preceding bend, and said second set of switches is arranged in a second plurality of groups of switches, one group for each of said stations, a different group of said second plurality being provided for control of the ram during the making of each bend having ram operating requirements parameters different from those of the next preceding bend, the combination further comprising: signal repetition selector means including a manually operable multi-position selector switch for each of said stations, for selectively repeatedly producing a ram stop signal at a position limit set by one of said sets of switches of said first set.
Claim 4
Dependent Claim
62 words
The apparatus of claim 1 wherein: means are coupled to said ram position indicating signal generating means, to establish a count reference at zero upon reversal of ram movement from a closing direction, all ram movement in an opening direction thereby being represented by forward counts from zero, whereby settings of said first and second switches are all referenced positively from zero.
Claim 5
Dependent Claim
66 words
The apparatus of claim 1 and further comprising: a hydraulic press brake having a ram controller including ram closing limit switch and a ram opening limit switch, said first output being coupled to said press brake ram controller in parallel with said ram closing limit switch, and said second output being coupled to said press brake ram controller in parallel with said ram opening limit switch.
Claim 6
Dependent Claim
41 words
The apparatus of claim 1 and further comprising: means for establishing a program for variably limiting the travel of a workpiece stop gauge mountable on the press brake, and including a third set of manually operated switches for gauge positioning control.
Claim 7
Dependent Claim
81 words
The apparatus of claim 5 wherein: said third set of switches is arranged in a plurality of groups of switches, one group for each of said stations, said plurality being provided for control of the gauge means during the making of each differnt bend, the groups of said third and fourth switches being arranged to correspond whereby for each station, there is a group of said first switches, a group of said second switches, and a group of said third switches.
Claim 8
Dependent Claim
34 words
The controller of claim 6 wherein said switches are thumbwheel operated switches having indicator digits directly associated therewith, each switch having digits zero through nine thereon representative of ten different switch conditions manually selectable.
Claim 9
Dependent Claim
21 words
The apparatus of claim 1 wherein: said ram position indicating signal generating means include a counter unable to count under zero.
Claim 10
Dependent Claim
39 words
The apparatus of claim 8 and further comprising: calibrate means coupled to said counter for entering and holding a zero in said counter during application thereto of an input such as to ordinarily cause said counter to count down.
Claim 11
Dependent Claim
70 words
The apparatus of claim 9 wherein said ram position indicating signal generating means include: an encoder having a portion adapted to mounting on a press brake ram and a portion adapted to mounting on a press brake frame for producing on two outputs, signals having a phase difference between them useful for detecting relative movement between said portions; and means for detecting the directions of relative movement between said portions.
Claim 12
Independent Claim
227 words
A method of making a series of bends on a workpiece in a press brake, comprising the steps of: establishing a program and entering into a controller a set of ram closed and ram open position designating signals representative of a series of positions to be reached and temporarily maintained, in a sequence, by the press brake ram; locating a workpiece between dies of the press brake and actuating the ram to make the first bend; limiting the closing stroke of the ram according to the first ram closing position designating signal entered in the controller; opening the ram and limiting the return stroke according to the first ram open position designating signal entered in the controller; relocating the workpiece between the dies; actuating the ram toward the workpiece in the second position to make another bend; closing the ram to the limit predetermined according to the ram closing position designating signal entered into the controller for said another bend; returning the ram to a limit predetermined according to the ram open limit position designating signal entered into the controller to follow said another bend; and continuing to reposition the workpiece after opening the ram on succeeding closure thereof to make additional bends in the workpiece, and limiting the length of return stroke of the ram following succeeding bends according to the program entered into the controller.
Claim 13
Independent Claim
227 words
A method of making a series of bends on a workpiece in a press brake, comprising the steps of: establishing a program and entering into a controller a set of ram closed and ram open position designating signals representative of a series of positions to be reached and temporarily maintained, in a sequence, by the press brake ram; locating a workpiece between dies of the press brake and actuating the ram to make the first bend; limiting the closing stroke of the ram according to the first ram closing position designating signal entered in the controller; opening the ram and limiting the return stroke according to the first ram open position designating signal entered in the controller; relocating the workpiece between the dies; actuating the ram toward the workpiece in the second position to make another bend; closing the ram to the limit predetermined according to the ram closing position designating signal entered into the controller for said another bend; returning the ram to a limit predetermined according to the ram open limit position designating signal entered into the controller to follow said another bend; and continuing to reposition the workpiece after opening the ram on succeeding closure thereof to make additional bends in the workpiece, and limiting the length of return stroke of the ram following succeeding bends according to the program entered into the controller.
Claim 14
Dependent Claim
67 words
The method of claim 11 wherein: the step of limiting the closing stroke includes substituting the output of the controller for the end of closing stroke limit switch of the press brake as the source of end of closing stroke signal, and substituting the output of the controller for the end of opening stroke of the press brake as a source of end of opening stroke signal.
Claim 15
Dependent Claim
24 words
The method of claim 11 and further comprising: the step of, prior to establishing a program, referencing ram opening travel from ram closed position.
Claim 16
Dependent Claim
53 words
The method of claim 13 wherein said referencing step comprises; generating pulses in response to ram closure and opening and so entering said pulses in a counter as to cause said counter to count down as said ram closes and count up as said ram opens and limiting the count down at zero.
Claim 17
Dependent Claim
36 words
The method of claim 14 wherein said referencing step includes: entering and maintaining a zero in said counter during closure of said ram until said ram is closed, and then counting up as the rams opens.
Claim 18
Dependent Claim
28 words
The method of claim 15 wherein the ram is referenced at zero with the workpiece in the space between a fixed and movable die of the press brake.
Claim 19
Dependent Claim
23 words
The method of claim 15 wherein the ram is referenced at zero with a fixed and movable die in contact with each other.
Claim 20
Dependent Claim
28 words
The method of claim 15 wherein: the referencing step is performed during a calibrate mode of operation, and the program is established during a run mode of operation.
Claim 21
Independent Claim
290 words
A method of making a series of bends in a workpiece in a press brake, comprising the steps of: establishing a program by mutually entering into a controller a set of gauge position designating signals representative of locations to be reached and temporarily maintained, in a sequence, by a workpiece positioning stop, and by manually entering into a controller a set of ram closed and ram open position designating signals representative of a series of positions to be reached and temporarily maintained, in a sequence, by the press brake ram; coordinaTing the gauge position designating signals with the ram position designating signals at each step in the sequence; locating a workpiece against the stop and between dies of the press brake and actuating the ram to make the first bend; releasing the ram and limiting the closing stroke according to the first ram closing position designating signal; releasing the ram and limiting the return stroke according to the first ram open position designating signal entered for the ram; moving the stop to the second position; locating the workpiece against the stop in the second position; actuating the ram toward the workpiece in the second position to make the second bend; closing the ram to the limit predetermined according to the ram closing position designating signal entered into the controller for the second bend; returning the ram to a limit predetermined according to the second ram open position designating signal entered to follow the second bend; and continuing the reposition the stop after each ram closing, and repositioning the workpiece against the stop after opening the ram each time; and limiting the depth of the ram stroke and return for each ram actuation according to the program entered into the controller.
Claim 22
Independent Claim
290 words
A method of making a series of bends in a workpiece in a press brake, comprising the steps of: establishing a program by mutually entering into a controller a set of gauge position designating signals representative of locations to be reached and temporarily maintained, in a sequence, by a workpiece positioning stop, and by manually entering into a controller a set of ram closed and ram open position designating signals representative of a series of positions to be reached and temporarily maintained, in a sequence, by the press brake ram; coordinaTing the gauge position designating signals with the ram position designating signals at each step in the sequence; locating a workpiece against the stop and between dies of the press brake and actuating the ram to make the first bend; releasing the ram and limiting the closing stroke according to the first ram closing position designating signal; releasing the ram and limiting the return stroke according to the first ram open position designating signal entered for the ram; moving the stop to the second position; locating the workpiece against the stop in the second position; actuating the ram toward the workpiece in the second position to make the second bend; closing the ram to the limit predetermined according to the ram closing position designating signal entered into the controller for the second bend; returning the ram to a limit predetermined according to the second ram open position designating signal entered to follow the second bend; and continuing the reposition the stop after each ram closing, and repositioning the workpiece against the stop after opening the ram each time; and limiting the depth of the ram stroke and return for each ram actuation according to the program entered into the controller.
Claim 23
Dependent Claim
77 words
The method of claim 19 wherein the step of manually entering a set of ram open position designating signals includes the step of: manually adjusting a set of multiposition thumbwheel operated switches in a plurality of different groups numbering at least as many as there are bends for which different ram open positions are to follow, adjusting the switches in each group in accordance with a dimension representing ram open position, to be attained following a bend.
Claim 24
Dependent Claim
24 words
The method of claim 19 and further comprising: the step of, prior to establishing a program, referencing ram opening travel from ram closed position.
Claim 25
Dependent Claim
53 words
The method of claim 21 wherein said referencing step comprises: generating pulses in response to ram closure and opening and so entering said pulses in a counter as to cause said counter to count down as said ram closes and count up as said ram opens and limiting the count down at zero.
Claim 26
Dependent Claim
36 words
The method of claim 22 wherein said referencing step includes: entering and maintaining a zero in said counter during closure of said ram until said ram is closed, and then counting up as the ram opens.
Claim 27
Dependent Claim
28 words
The method of claim 23 wherein the ram is referenced at zero with the workpiece in the space between a fixed and movable die of the press brake.
Claim 28
Dependent Claim
23 words
The method of claim 23 wherein the ram is referenced at zero with a fixed and movable die in contact with each other.
Claim 29
Dependent Claim
175 words
Apparatus for controlling the ram of a hydraulic press brake during the procedure of making a series of bends in a workpiece; said apparatus comprising: establishing means for establishing a program for variably limiting the travel of a ram of a press brake at different steps in the series for workpiece bends having different parameters, first and second signal outputs, said first output being for a ram closing limit signal and the second output being for a ram opening limit signal; ram position indicating signal generating means having an output; and signal comparing means having inputs coupled to said generating means and to said establishing means for detecting a match between signals from said generating means and signals from switches during opening and closing movement indicating signals from said signal generating means, to generate a ram stop signal at said first output when a match is made during indication of ram closing movement, and to generate a ramp stop signal at said second output when a match is made during indication of ram opening movement.
Claim 30
Dependent Claim
175 words
Apparatus for controlling the ram of a hydraulic press brake during the procedure of making a series of bends in a workpiece; said apparatus comprising: establishing means for establishing a program for variably limiting the travel of a ram of a press brake at different steps in the series for workpiece bends having different parameters, first and second signal outputs, said first output being for a ram closing limit signal and the second output being for a ram opening limit signal; ram position indicating signal generating means having an output; and signal comparing means having inputs coupled to said generating means and to said establishing means for detecting a match between signals from said generating means and signals from switches during opening and closing movement indicating signals from said signal generating means, to generate a ram stop signal at said first output when a match is made during indication of ram closing movement, and to generate a ramp stop signal at said second output when a match is made during indication of ram opening movement.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-31 | 1978-09-30 | 1979-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-31 | 1982-09-30 | 1983-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-31 | 1986-09-30 | 1987-04-01 | $7700.00 | Window Closed / Lapsed |