US3895509A - Bending machine for rods, wires and other elongated articles of steel, etc. - Google Patents

Abstract

A bending machine for elongated articles in which a rotatable bending platen supports bending tools, adjustable setting means control the rotation of the bending platen through predetermined principal bending angles, with an electrically operated control system continuining any bending operation through a predetermined supplementary angle after bending through the principal angle has been accomplished. An adjustable delay device is operably associated with each principal bending angle and is arranged to coact with a motor for driving the bending platen so that the motor remains activated for a further period of time after a given principal bending has been reached for effecting bending through the supplementary bending angle.

Description

United States Patent 1 1 Peddinghaus 1 1 July 22, 1975 [76] Inventor: Carl Ullrich Peddinghaus, Obere Lichtenplatzer Str. 276, 56 Wuppertal-Barmen, Germany 221 Filed: May 18,1973

121 Appl.No.: 361,849

Related U.S. Application Data [63] Continuation-in-part of Scr. No. 94,251, Dec. 2,

1970, abandoned.

3,661,002 5/1972 Peddinghaus 72/21 3,670,541 6/1972 Peddinghaus 72/8 3,717,016 2/1973 Peddinghaus 72/D1G. 22 3,772,905 1 1/1973 Peddinghaus 72/22 3,777,525 12/1973 Peddinghaus 72/22 Primary ExaminerC. W. Lanham Assistant Examiner-D. M. Gurley Attorney, Agent, or FirmHolman & Stern [5 7] ABSTRACT A bending machine for elongated articles in which a rotatable bending platen supports bending tools, adjustable setting means control the rotation of the bending platen through predetermined principal bending angles, with an electrically operated control system continuining any bending operation through a predetermined supplementary angle after bending through the principal angle has been accomplished. An adjustable delay device is operably associated with each principal bending angle and is arranged to coact with a motor for driving the bending platen so that the motor remains activated for a further period of time after a given principal bending has been reached for effecting bending through the supplementary bending angle.

3 Claims, 6 Drawing Figures PATENTEDJUL22 ms 3.895.509

SHEET 1 i U J57 FIG.2

PATENTEDJUL22 I975 3.895509 sum 2 FIGA PATENTEDJUL22 ms WT 3.895509 FIG.6

BENDING MACHINE FOR RODS, WIRES AND OTHER ELONGATED ARTICLES OF STEEL, ETC.

BACKGROUND OF THE INVENTION This application is a continuation-in-part of my copending application Ser. No. 94,251 filed Dec. 2, 1970, now abandoned.

This invention relates to a bending machine for rods, wires and other elongated steel articles and other materials of the type comprising a drivable rotatable bending platen which carries a pair of bending tools, an adjusting member operably associated with the bending platen and which has adjustable means capable of being set in various positions corresponding to a variety of desired principal bending angles, with the arrangement being such that a bending process which involves the formation of a plurality of bends in an elongated article can be automatically effected by means of said bending platen and the adjustable means in an electrically controlled sequence.

In my prior U.S. application Ser. No. 879,428 filed Nov. 24, 1969, now abandoned, there is disclosed such a bending machine which comprises a bending platen for supporting the bending tools, with the bending platen being rotatable and drivable in either predetermined angular direction, adjustable setting means operably associated with the bending platen for controlling the rotation of the platen through predetermined principal bending angles, with the adjustable setting means having adjustable elements which can be set to correspond to a series of principal bending angles and which can be actuated in any desired sequence, as well as an electrically operated control system for continuing any bending operation through a pre-determined supplementary angle after bending through the principal bending angle has been achieved It was suggested in the above mentioned application to operate in any convenient way, the control for the individual principal bending angles by using several successive adjusting switches and to condense these individual control circuits into a bending sequence routine which can be carried out step by step and which can be scanned with the aid of a step-by-step circuit, Further, for determination of the bending angle which is acutually reached by the bending platen according to my further U.S. patent application Ser. No. 36,990 filed May 13, 1970, now U.S. Pat. No. 3,717,016, and U.S. Pat. application 879,428, the use of an impulse counting device was suggested. In such an arrangement, an impulse counting instrument or accelerating relays are connected to an impulse sender which is operated by the adjustable elements of the adjustable setting means whereby the switch of the drive motor is deactivated after having reached the preselected number of impulses corresponding to the desired bending angle. In patent application Ser. No. 879,428. it was furthermore suggested to continue the principal bending process around an additional or supplementary bending angle after the normal deactivating position. The additional bending angle can be determined by measuring at least one part of the energy or current absorption of the drive motor in the elastic deformation region of the material being bent and this procedure enables any deviation from the planned principal bending angle to be compensated. Up to the present, such a compensation has been obtained by changing by hand the adjustable elements on the adjustable setting means after having empirically determined the compensation which is necessary. Thus, for this process, small adjusting pins may be plugged into holes of an annular ring with which the adjustable setting means is provided. This procedure may not only cause mistakes, but is, on the other hand, rather inaccurate and is very often difficult to carry out, for instance, when the adjusting holes are frozen or dirty.

OBJECT AND SUMMARY OF THE INVENTION The object of the present invention is to provide a bending machine in which such compensation can be effected in an improved manner.

In accordance with the invention, there is provided a bending machine for rods, wires and other elongated articles of steel and other materials comprising a bending platen for supporting bending tools, said bending platen being rotatable and directionally controllably driven, a drive motor for the platen, setting means operably associated with the bending platen for principal bending angles, the setting means having elements which correspond to the specific principal bending angles and which can be actuated in any desired sequence, an electrically operated control system for automatically continuing a bending operation beyond a set principal bending angle to compensate for deviations between the actual bending angle achieved, and the required bending angle which may otherwise occur, the improvement being there is provided in association with each principal bending angle, an adjustable time delay device with the aid of which the bending platen drive motor, after having reached a given principal bending angle, remains activated for a further period of time without changing the position of the setting means, and each delay device being defined by an adjustable potentiometer arranged to vary the timing constant of a condenser/resistor link.

The electrical delay device for each principal bend-. ing angle (such as, for instance, 45, and conveniently comprise potentiometers which alter the timing constant of a capacitor-resistor link.

The construction can be simplified by having, in association with the potentiometers, corresponding in number to the principal bending angles, a common condenser and a common resistor for discharging the condenser. The charging of the condenser is arranged to commence as soon as a relay is actuated to deactivate the bending platen drive motor, with the drive motor then continuing to operate, however, through a bridging circuit, With such an arrangement, it is possible to use a glow-lamp or the like as a discharging resistor. As soon as the condenser is charged to a level that the ignition voltage for the lamp is exceeded, the discharging current starts to flow and excites a further relay connected in the condenser/resistor circuit by which the drive motor is finally switched off or switched over into its return travel movement.

In practice, it is usual to operate with different speeds of rotation of the bending platen depending on the thickness of the article to be bent. Thus, there are conveniently provided delay device with several scales. Adjustable potentiometers are specially suitable, with each scale of a potentiometer being associated with a different driving speed, and having markings proportional to the different driving speeds. Hence, a predetermined compensation for any given bending angle with an particular article to be bent can always be achieved independently of the bending speed at the time.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is further explained with the aid of drawings referring to one example of a bending machine in accordance with the invention. In the drawings,

FIG. I shows diagrammatically an arrangement of individual adjusting switches in the overall programme circuit,

FIG. 2 shows diagrammatically an arrangement of electrical delay devices,

FIG. 3 shows scales on a potentiometer,

FIG. 4 is a plan view of a bending platen,

FIG. 5 illustrates setting means according to the invention with the central circuit, and

FIG. 6 illustrates the control circuit.

Referring to FIG. 1, a scanning switch 51 is provided which is movable step-by-step from its starting position at the beginning of each bending process, and which establishes connections to the individual adjusting slides 26 of which only one is illustrated in FIG. 1 because of lack of space. If one of the slides 26 is switched on zero, the scanning switch 51 carries on running, but if an adjusting slide 26 is in a position other than zero, the scanning switch is prevented from continuing until the bending platen 1 has terminated its return travel after its forward travel. The principal bending angles for a bending sequence are pre-selected with the aid of the adjusting slides 26 and during each bending in the bending sequence, the associated relay 27 (when excited) keeps the bending platen drive motor 28 activated.

As shown in FIG. 2, three further contacts 52', 52 and 52" are provided. These contacts can be preselected with the aid of the adjusting slides 26, depend ing on whether an angle of 45, 90 or 180 is set. Each of the three contacts 52, 52" and 52" is connected to one of three adjustable potentiometers 53', 53" or 53", which collectively lie in the circuit ofa condenser 54. The condenser 54 charges within a time which de pends on the adjustment of the mentioned potentiometers and discharges via a resistor in the form of a glow lamp 55 and a further relay 56. In order to effect the charging of the condenser, there is a contact 57 which is closed at the same time as the corresponding relay 27 starts to de-energize. Such de-energization of the relay 27 would normally open the circuit of the drive motor. The relay 56, however, keeps the drive motor activated in a bridging circuit as long as it is not excited by the discharging of the condenser 54. This bridging circuit is switched parallel to the drive motors circuit, which can be seen in FIG. 6.

In the circuit of FIG. 2, there is the relay 56 which, as above pointed out, keeps the drive energized and only disconnects it if it is excited by the discharging of the capacitor 54. The relay 56 has been illustrated in the usual manner but without contacts. That the contacts close a bridging circuit through which the drive motor remains connected is above pointed out. The switch 51 in FIG. 1 is a stepped switch which, as described above, switches on step-by-step from its starting position, making connections to the adjusting slides 26 (of which only one is shown). This stepped switch is driven with the aid of a motor 22 as shown in FIG. 5 and which is described hereinafter. The stepswitching motor also turns a control cylinder 23 which has individual adjusting slides. It can also be seen from FIG. I that several adjusting slides or adjusting switches 26 can be provided if a particular bending programme involving several bends is to be run automatically. If this is not the case, one adjusting slide or adjusting switch 26 is sufficient, with such slide or switch activating the contacts 52', 52", and 52" according to its setting. Of course. if an automatic programme is being carried out, the contacts 52'. 52" and 52" can only be effectively closed by that adjusting switch or adjusting slide 26 for which the bending is set at the time with the aid of a step-switching motor 22. This does not alter the fact that the selection of the contacts 52. 52". or 52" is made according to the choice of the bending angle which is always pre-selected with the switch or slide 26. In a multiple programme, the circuits in FIG. 2 must naturally also be multiple. In other words, in FIG. 2, the time delay circuit for one adjustment slide or switch is reproduced.

It can be seen from FIG. 1 that there are, in fact, several, as further relays have been drawn in, equal to the relay 27. Of course, one can repeat the circuit in FIG. 2 several times in the drawing, but it should be sufficient if it is shown once as is the case. The specification states that only one adjusting switch 26 is shown and this applies also to the relays in the circuits of FIG. 2.

The disc 4 which rotates with the bending plate, can rotate either in a clockwise or counterclockwise direction. Hence, the sector-shaped contacts 19, 20 or 21 of the disc 4 must be twice the size of the predetermined angles to allow for rotation in either direction. If, therefore, an adjusting slide 26 is set, for example, in a central position as illustrated in FIG. 5, only the connection between terminals 20 and 20 made by the sector-shaped contact 20 is operative.

FIG. 3 shows a suitable construction of adjustable scales on an adjustable potentiometer 53. The central adjusting button thereof is surrounded by three concentric scales 58, 58" and 58". The inner scale is only provided with markings over an angle of 120, the center scale over an angle of 240 and the outer scale over its whole range. Such a scaling corresponds to three different driving speeds, which stand in a ratio of 1:2:3 to one another. The inner scale 58' is associated with the slowest driving speed, the center scale 58" with a doubled driving speed and the outer scale 58' with a trebled driving speed. In this way, one can precisely compensate for the bending angle error for each driving speed, once such error for a certain material and a certain dimension is known.

The invention is not to be confined to any strict conformity to the showings in the drawings but changes or modifications may be made therein so long as such changes or modifications mark no material departure from the spirit and scope of the appended claims.

DETAILED DESCRIPTION OF THE INVENTION A bending platen 1 shown in FIG. 4 supports two bending tools 2 and 3 which may be bending bolts of circular cross section or of some other configuration. The bending platen 1 is surrounded by an annular disc 4 provided with sector-shaped slipring contacts 19, 20 and 21, corresponding to the principal bending angles 45' 90 and l.

Starting from the zero position, contact positions 19', 19" or 20', 20" or 21', 21", each of which is disposed at an axial distance on the circumference of a drum 23. driven via a motor 22, may be brought to bear on the slip ring contacts 19. 20, and 21. The motor is driven in steps and the contact positions are located on the drum in a multiple arrangment sequential in the circumferential direction of the drum 23. For example, it is possible for eight such arrangements to be provided.

A contact ring 24. on which a contact spring bears. is provided on the drum 23 and the ring 24 is slidingly joined to an adjustment slide 26 by means of which the contact ring 24 may be optionally switched to one of the contact positions 19'. 20' or 21. The contacts 19', 20 and 21" located opposite the components 19, 20 and 21'. are all connected to each other and to a relay 27 illustrated in FIG. 6. The sectorshaped contacts 19. 20 or 21 of the disc 4, on which a control circuit response. will depend on the position of the slide 26. lf, for example. the slide 26 is moved into its middle position. only the contact position 20 will be suppled with control current. The contact position 20 will be maintained by the contact ring 24 for so long as the disc 4 rotates over the zone from 0 to 90. Subsequently. the contact between position 20 and 20" will once again be opened. The relay 27, energized by one of the above mentioned contacts. controls a motor 28 for driving the bending platen 1.

Each adjustment slide 26 is also operably associated with a reversing switch 29, and by means of which the drive can be switched to clockwise or counterclockwise rotation. respectively. Hence. the slip ring contacts 19. 20, 21, on the annular disc 4 are provided in both directions. with the drum 23 being disposed in the middle position.

Since three positions are required for the adjusting slide 26 to correspond to the angles 45, 90 and 180 and two positions are required for the reversing switch 29 corresponding to clockwise and counter-clockwise operation. it is possible for the adjustable slide 26 and the reversing switch 29 to be electro-mechanically controlled in accordance with the appropriate bending sequence programme. for example. by means of punched cards or by means of known five-track punched tape so that the orders for one day may be prepared by a central order preparation department.

I claim:

1. A bending machine for rods, wires and other elongated articles of steel and other materials. including a bending platen for supporting bending tools. said bending platen being rotatable and directionally controllably driven, a drive motor for the plate. setting means operably associated with the platen for principal bending angles, said setting means having elements corresponding to the specific principal bending angles and which can be actuated in any desired sequence. an electrically operated control system for automatically controlling a bending operation beyond a set principal bending angle to compensate for deviations between the actual bending angle achieved and the required bending angle which may otherwise occur. the improvement being there is provided in association with each principal bending angle, an adjustable time delay device. with the aid of which the drive motor for the platen, after having reached a given principal bending angle. remains activated for a further period of time without changing the position of the setting means, and each delay device comprising an adjustable potentiometer arranged to vary the timing constant of a condenser/resistor link.

2. The bending machine as claimed in claim 1, in which there is provided a common condenser and a common discharging resistor for the potentiometers.

3. The bending machine as claimed in claim 1, in which each potentiometer is provided with a plurality of scales, each of which is associated with a different driving speed and which has markings proportional to its associated driving speed.

Claims (3)

1. A bending machine for rods, wires and other elongated articles of steel and other materials, including a bending platen for supporting bending tools, said bending platen being rotatable and directionally controllably driven, a drive motor for the plate, setting means operably associated with the platen for principal bending angles, said setting means having elements corresponding to the specific principal bending angles and which can be actuated in any desired sequence, an electrically operated control system for automatically controlling a bending operation beyond a set principal bending angle to compensate for deviations between the actual bending angle achieved and the required bending angle which may otherwise occur, the improvement being there is provided in association with each principal bending angle, an adjustable time delay device, with the aid of which the drive motor for the platen, after having reached a given principal bending angle, remains activated for a further period of time without changing the position of the setting means, and each delay device comprising an adjustable potentiometer arranged to vary the timing constant of a condenser/resistor link.

2. The bending machine as claimed in claim 1, in which there is provided a common condenser and a common discharging resistor for the potentiometers.

3. The bending machine as claimed in claim 1, in which each potentiometer is provided with a plurality of scales, each of which is associated with a different driving speed and which has markings proportional to its associated driving speed.

Images