DE1752006A1 - Shear line for trimming and dividing sheet metal, especially heavy plate - Google Patents

Description

Management company 667 St. Ingbert, March 18, 1968

Moeller & Neumann Pa 327 - 396 / AP 1752006

open hands is society

"Shear line for trimming and dividing sheet metal, especially heavy plate"

The invention relates to a shear line for trimming and dividing Sheets, in particular heavy sheets, in which two long-knife trimming shears are set up opposite one another within the roller table of the shear line that are followed by a partial scissor. Trimming shears set up opposite, which among other things lead to a considerable shortening of the shear line lead, have become known as "double trimming shears". In the following, the opposite trimming shears are called double trimming shears designated.

In front of a double trimmer, the sheets only need to be aligned once to be and run through the double trimming shears in a single clamping between drive rollers or on tensioning carriages in order to make them true to the edges to be pushed forward for trimming in increments. It has been shown in practice that the installation of a double trimming shear is not only possible with New buildings - because of the shortening of the scissor line and because of the elimination of the double conducting devices in front of the conventionally staggered ones Trimming shears are worthwhile, but also the production of double trimming shears on sheets trimmed without bumps can get so high that one gets into time hot when operating the dividing scissors. Because of the savings in set-up time is namely the production of a double trimmer: f so far too increase that the significantly heavier and thus slower cutting dividing scissors, in front of which the metal sheets are oriented towards free outlet and may have to be marked, the increased production of the double trimming shears! unable to process.

The aim of the invention is to eliminate the bottleneck TVüschere /.u without Setting up a second part c. Here in a parallel scissors line of refuge to have to take what would be obvious. Based on a Schertnlirue of the aforementioned kind, where the 1st Ui ih

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feed by at least one of the knife movements of the continuous driven trimming shears takes place depending on the actuatable drive roller pair at intervals, it is proposed in solution of the problem that the dividing shear is a so-called Roilschnittschere with a rocking movement executing curved knife and is set up at such a short distance behind the trimming shears that the sheets without free outlet in the clamping be subdivided by the pair of driving rollers, the last feed interval of which can be shortened independently of the drive of the trimming shears is.

This ensures that the production of the scissors line alone after the production of the double trimming scissors and the operation of the Partial scissors do not give cause for stays. Because of the short distance between double trimming shears and dividing shears, there is no need to realignment of the sheets in front of the dividing shear, because the partial cuts in the clamping of the sheet by the drive rollers of the trimming shears take place and accordingly the partial cuts are necessarily at right angles to the trimmed sheet metal edges.

Furthermore, the means is selected by the drive roller feed with which the coefficient of friction between Rolls and sheet metal can greatly increase, so as to achieve the shortest possible acceleration values to come for sheet metal transport. This makes a decisive contribution to the production of the double trimming shear by the dividing shear bring to.

Finally, you have to choose a rolling shear with a curved cutting blade the shortest possible working cycle due to the small strokes of the drive crankshafts, which are particularly small when the

of the one knife,
Radius of curvature is chosen to be at least 30 m, preferably 60 m »

A side effect of the features of the invention is that the overall length the scissors line is shortened even further. The conducting devices also fall in front of the dividing scissors. This is known per se for trimming and dividing sheet metal stacks (DRP 526.671), but it is stated in this known cases, the combination of double trimming shears and partial

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scissors into a unit unrelated to that of scissor lines for heavy plates the problem of throughput of the increased production of a double trimming shear by a dividing shear exists. This problem does not apply namely, if with opposing trimming shears through a single one Cutting stroke sheet stacks can be trimmed over their entire length. Sheet metal packages do not arrive in as quick a sequence as those in one rolled slab contained sheet metal.

With a double trimming shear, the feed rate for the Sheets to be trimmed intermittently are derived from the continuous drive of the trimming shears, the feed being adjusted to the respective knife length of the Trimming shears is coordinated. The last feed interval of the driving roll frii is according to the invention in order to be able to cut cutting lengths deviating from the feed intervals, regardless of the continuous drive of the trimming shears can be shortened, both arbitrarily for scooping the front and rear sheet metal ends, as well as controlled by the signals of a length measuring device, the sheet length required after the cropping cut can be adjusted.

On this point, too, one of several options is selected because one could also use all the feed intervals contained in the desired sheet metal length Shorten proportionally so that the sheet length is always an integral multiple of the calculated and shortened feed interval. With these However, particularly with short cutting lengths that are only a little more than 1 to 2 times the maximum feed interval, the method would first shortened feed intervals are unfavorably small, so that the lateral guide the front trimmed sheet metal edges would not be optimal for the sheet to run straight out.

The invention also includes a control for shortening the last feed interval of the drive rollers according to the measured values of a length measuring device, which are compared with preset values of the desired sheet metal length and which stops the drive rollers when comparing zero. (Claim Z)

Another object of the invention is to avoid that the M Do not place the transverse knife attached to the trimmer sufficiently far from the transverse knife cutting edge of the penultimate cut and thereby

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not penetrate. This danger exists if the desired sheet length is only is little greater than a multiple of the fixed or set feed interval s. If this can be overlooked after a preliminary calculation, the control ensures that the penultimate feed interval is also shortened, whereby the last feed interval is brought to at least the size, e.g. at least one sheet thickness at which the cross knives are certain incise. (Claims 3 and 4)

To save even more time, the control system provides for an automatic release the dividing shear when the drive rollers come to a standstill. (Claim 5), preferably at a time shortly before the shutdown of the drive rollers to the Acceleration time of the dividing scissors can still be covered with the sheet feed. (Claim 6)

Conversely, the sheet feed should be done before the dividing shear comes to a standstill are triggered after the severing cut has been carried out at the point in time when the retracting cutting knife is out of cut. (Claim 7) With a dividing scissors With two offset crank drives, this is achieved by means of contactors that can be adjusted via the crank path of the trailing crank. (Claim 8).

In the drawing, a short overall length is shown as an exemplary embodiment shown according to the invention, namely show:

1 shows a side view of a double trimming shear and a partial shear set up shortly behind it,

2 shows a plan view of the scissors unit built into a roller table,

3 a - e a schematic representation of the crank drive of a roll cut dividing shear with five different ones Positions of the upper knife,

4 shows an electrical circuit diagram for the arbitrary and controlled stopping of the drive rollers or Feed means,

1 0 9 8 12 "/ 0 5 3 5

Fig. 5 a and b two representations of a sheet with the for Understanding of the control according to the invention for setting the desired sheet length is required Information, and

6 shows a block diagram of a control for shortening also a penultimate feed interval.

Fig. 1 and 2 show one within the scissors line with the roller table rollers 2 set-up movable trimming shears Di and a stationary trimming shear Ü2 »the opposite set up a double trimming shear represent. In the area of the double trimming shears, the sheets are clamped by pairs of drive rollers 4 and 6 and pushed forward with absolutely correct edges, after which the trimmers passing through make their cuts.

Shortly behind the double trimming shear there is a partial shear T that has behind the knife plane a pair of driving rollers 8 in order to pull through the last sheet metal end when it has left the driving rollers 6. At least the roller table rollers within the dividing scissors T are namely loose rollers. A pair of feeler rollers 10 in front of the knife level, one of which Roller is driven, is used to measure the length of sheet metal passing through, as will be explained below. 12 is an end pusher of conventional design. To the Metal sheets, when they have left the pair of driving rollers 4 with their rear ends, are still to be pushed forward with their edges aligned, are outriggers on each trimming shear 14 arranged with guide rollers 16. The sheets are thus clamped in the dividing scissors T by the feed and guide means 4, 6, 16 of the double trimming shears.

The dividing scissors T are so-called roll cut scissors with a rocking cut moving upper knife, which has a curved cutting edge. The knife movements of such a known pair of scissors are based on Fig. 3 explains in more detail. This is a schematic representation of the cutting, curved upper cutter 18, the fixed lower cutter 20 and two connecting rods articulated at a distance from one another on the upper cutter 18 22, 24 to be seen, which are driven by crank pins 26, 28. The Tt-iLe designated by 18 and 20 can also be regarded as knife carriers wet-el

1 0 9 & 3-2 / 0535

Fig. 3a is the starting position in which the displacement of the crank drives is recognizable.

When the dividing scissors are switched on, the crank pins -26 move, 28 counter-clockwise according to the arrow directions. In Fig. 3c, where the crank pin 26 approximately in bottom dead center the cut is halfway through.

To Fig. 3d both connecting rods 22, 24 are approximately mirror images, and in 3e the section is completed, after which the crank pins 26, 28 are stopped in the position according to FIG. 3a.

An advantageous mode of operation of the double trimming shear / dividing shear unit according to the invention is explained with reference to the circuit diagram of FIG. Here 32, 34 mean the power lines of an auxiliary control circuit, the line pair 36 the network for operating the motors T of the dividing shears and the line pair 38 the network for operating the motors V of the feed means, i.e. the pairs of driving rollers 4, 6, 8 and 10 and the driven roller table s roll 2.

It has already been stated that the feed means are switched on intermittently, derived from the trimming shears Di and D ^ passing through. This is done by a control cam disk 40 placed on a crankshaft of the trimming shears, which rotates in the indicated direction of rotation and is about to close a switch 41 via a foil 42 during the return stroke of the trimming shears. As a result, a relay 44 is energized, which closes the switch 46 in the network 38 and switches on the motors labeled V of the feed means. The switch 41 opens automatically under spring pressure when the cam disk 40 releases the button 42.

Since the front end of the sheet must first be scooped up, it is intended that that the feed means, which normally perform a fixed feed path according to the knife length of the trimming shears, are arbitrary can be shut down. This is done by a push button 48, by means of which the relay 44 is de-energized, even when the cam disk 40 keeps switch 41 closed. By pressing the push button 48, not only does the switch 50 open, but it closes

10-9 ^ 32/05 35

The switch 52 is also in the control circuit of a relay 54, which when energized the switch 56 in the network 36 closes, whereby the motors labeled T the dividing scissors are switched on. A holding contact, not shown, keeps the switch 52 closed and the switch 50 open until a The working cycle of the dividing scissors is finished.

With the execution of the first crop cut, a length measurement must be carried out begin to advance a specified sheet length into the dividing scissors, regardless of how many strokes the double trimming scissors are doing executes. The feed means must therefore respond to the signal from a length measuring device can be stopped in a controlled manner. , Referring to Fig. 1 it can be seen that one of the feeler rollers 10 with an encoder 58 is connected, which depends on the number of revolutions Counting pulses, which represent a first signal proportional to the sheet length advanced, are passed on to a first comparator 60. The comparison device 60 also receives the pulse sum from a preselector 62 as a second signal proportional to a desired partial length. By continuously comparing the first signal with the predefined second signal in the comparison device 60, the comparison device 60 uses the line 64 a pulse is given to stop the feed means when the comparison results in zero.

Returning to the circuit diagram of FIG. 4, it should be noted that the the stop pulse leading line 64 carries control current and is closed in the comparator 60 by a switch 66 when the value of zero des Target / actual value comparison achieved, i.e. the desired sheet length due to the presetting in the device 62 has run through. When switch 66 is closed, relay 68 is energized, switch 70 is opened and the switch 72 closed, which is located in the loop 74 of the control line 76. Opening the switch 70 has the same effect as the push-button switch 50, i.e. the feed means are stopped independently of the drive of the trimming shears. If the switch 72 is closed, it becomes like when the switch 52 is closed - the relay 54 is energized and the scissors section is automatically switched on by the stop pulse. At the same time is blocked by the currentless relay 44 of the feed drive.

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So that the length measurement starts exactly with the first crop cut, it works from the control line 76 a branch line 78 to a ballast 80 of the transmitter 58, which carries a voltage pulse when pressed of the push button 48 for triggering the forehead cut of the switch 52 in line 76 is closed. This voltage pulse has the effect in the ballast 80 that the encoder 58 is continuously controlled by a feeler roller 10 output rotation signals as the first signal during the or the next feed interval triggered by the cam disk 40 the first comparison device 60 passes on.

The circuit is expediently improved so that the Comparison device 60 shortly before the end of the setpoint / actual value comparison sends an impulse to a relay that decelerates the feed mechanism to creep speed so that the sheets do not pass through when the machine is finally brought to a standstill their inertia continues to run.

As far as described so far, the control of the shear line ensures that the last feed interval can be shortened independently of the continuous drive of the trimming shears, namely independently of the revolutions of the cam disk 40. To explain this process, reference is made to FIG. 5a. Here a section of a metal sheet 81 is shown which has an indefinite length from the line 85 of a separating cut of the dividing scissors T from. The cut along line 85 may have been arbitrarily initiated by pressing push button 48 (FIG. 4). The intermittent length measurement is enabled by the voltage pulse going over the line 78 to the device 80. _{The feed intervals V 1} , V ₂ , V ₃ , V ₄ run one after the other.

Lp denotes the desired finished length of a metal sheet, in which a multiple of V does not go, rather the partial cutting line 87 lies within the next feed interval ν_, which must be shortened by the distance _ \ V-. This is done by the set-actual value comparison in the first comparison device 60, in which the actual value of the sheet length V, + V ₂ VJ + V ^ + (V5 - Jj ^ Vtj) as the first signal is compared with the desired sheet length Lp as the preset second signal. When comparing zero

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the feed is stopped by closing the switch 66 in the device 60 and the dividing shear is set in motion, whereby precautions can still be taken in terms of control, the sheet feed is delayed via slow speed shut down and switch on the dividing scissors as part of their inertia shortly before the sheet metal comes to a standstill.

It can now happen that a desired sheet length is only slightly more than a multiple of the feed interval. In such a case it is not only difficult, after the end of the last full feed interval V ^, to drive the small remaining feed precisely, but there is also the risk that the oversize blades of the double trimming shears D ,, D? Find too little "meat" and slide off when the remaining feed is between zero and, for example, the sheet thickness, in order to specify a limit for the risk of slipping.

Such a case is to be calculated in advance, since z. B. continuously the difference between the second signal L._ and the first signal L _e ff _# ^ _he passed through

Sheet length can be determined and examined whether there will be a difference L ₁ -, - L ££ between a full feed interval V and V + sheet thickness d. Reference is made to FIG. 5b. _{The trimming cuts corresponding to the feed intervals V 1} to V4 are drawn along the line 89 on the upper edge of the metal sheet 83. It can be seen that with a desired sheet metal length L ₁ -, after completion of the last full feed interval V4, only a residual feed V is required in order to still cut off the small seam piece 91. If V is less than the sheet metal thickness d, the difficulties mentioned arise, regardless of whether the severing cut with the transverse knife takes place immediately after the longitudinal cut or after the next working cycle of the trimming shears, at least with regard to the difficulty of feeding on small paths .

So if a computational test results in the ratios according to FIG. 5 b above, then provides a further developed within the scope of the invention control according to claims 3 and 4, or according to FIG. 6, that the penultimate Vox shoe step V ^

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is shortened so far that V ^ + V is divided into two partial feeds, each of which is so large that the cross knives cut safely into the trimming cut and / or the feed control including a delay there is enough time before the shutdown for the shutdown processes to proceed properly.

At the lower sheet metal edge in Fig. 5b it is indicated that when the condition is met

^L F - ^L eff. > ^V 4 ^ s. ^V 4 ^{+ d}

the second, preset signal L ^, corrected by - A Vy. that is, a shortened first partial feed / \ V is set, which is followed by the second partial feed ^ i V 2, which triggers the partial cut, under the guidance of the zero comparison in the device 60, both of which are sufficiently large. After the first partial feed J ^ Vj, a shortened hem strip 93 is cut off, followed by a residual strip before the partial cut after the line 95 in the double trimming shears.

The one required to shorten the penultimate feed interval Control shows in the embodiment of FIG. 6. It can be seen that the elements 10, 58, 60, 62, 64, 78, 80 and the the actual feed control 44, 46 and the dividing scissors control 68, 72, 54, 56 are expanded by a device complex, which is indicated by the dashed line Line 43 is outlined.

Furthermore, a pulse counter 45 for partial feed lengths is also shown, which receives its pulses from the encoder of the measuring rollers 10 via line 47 and emits a pulse sum signal corresponding to _{the actual feed interval I »ef f via line 49.}

The additional elements within the line 43 initially include a difference _{device 61 for ongoing mapping of the difference Lp - L ß} ££ (Fig. 5b) from the signals of the preselector 62 and the transmitter 58 as well as a second downstream comparison device, or a discriminator 63 for Determining if at some point the condition

^L F - ^L eff> V ^ V + d

- 11 -

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is fulfilled, ie after a last feed, eg V _4> a too small remaining feed V '<^ d remains. If this is the case, then a pulse goes over the line to the changeover switch 67 and switches the switch 69 from the normal position shown, secured by spring pressure or the like, to the contact 71. In the normal position of the switch 69 is the full feed length corresponding control variable V which is inserted through the control disc 40, 41 of FIG. 4, via line 73 to a third comparative device 75 for zero comparison, V = V _eff ge on, whereby on the Line the normal feed control 44, 46 is operated for full feed lengths. In addition, a line 84 goes from the feed device 40, 41 to a summation device 86 in which the value d coming from the preselector 88 is added to V. This sum V + d goes to the second comparison device

In the switching position of the switch 69 on contact 71, a preselector for the control variable of the shortened first partial advance length ^ JV ^ is connected to the comparator 75. Since after each stop of a feed from the feed control 44, 46 via the line 82 a pulse to delete the pulse sum goes in the counter 45, the actual value V _{ff of} the sheet feed within a feed interval is constantly in the line 49. By comparing this value V with the value Vj, which is preset to about half of a full feed interval V at 79, the third comparator 75 now delivers a premature stopping pulse so that the trimming shears only cut off the seam strips 93.

Soon after the partial feed «£ \ Vj begins, the difference Lp - L _e ££ in the devices 61 and 63 is less than V, ie the pulse going over the line 65 goes out, the switch 69 falls back to the normal position and the The control is set to "full feed intervals". However, it is now overwritten by the zero comparison in the first comparison device 60, which is transmitted via line 64 when L "= L,. a pulse to both the feed control 44, 46 to stop the remaining feed Δ. V £ as well as to the partial scissors control 68, 72, 54, 56 for triggering the partial cut.

The control according to Fig. 6 in connection with Fig. 5b is geared towards

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17S2ÖÖ6

from the difference L - L ,, to deduce a last, too small residual feed V ¹ and then to divide the remaining total feed into two partial feeds until the desired sheet length is reached. Of course, there are other ways of solving the problem of providing two last, approximately equal partial feeds for each finished length Lp, e.g. B. by computationally investigating whether a comparison of Lp with all possible n-fold feed intervals ^{results in a residual amount V 1 that} is smaller than an "too small" amount d. Generally speaking, the invention therefore comprises a controller according to claim 3.

Furthermore, the amount d was defined as the best thickness. When the trimming shears but do not have any transverse knives on the inlet side, but only on the outlet side (British patent specification 991.343), which means that the problem of the insecure cross-knife cut does not arise when the residual feed V is too small, then d is chosen solely from the point of view of setting a sufficiently long last partial before thrust. A feed is closed under "long enough" understand where the feed motors are given time from a ramped up constant speed depending on the path - namely through a setpoint / actual value

TO comparison, e.g. B. after Lp = L _g ££ - so specifically shut down that the

desired feed length is obtained exactly.

In this respect, the special before thrust control according to FIG. 6, or the claims 3 and 4 regardless of whether the dividing scissors is a rolling shear or not, and whether the sheets are advanced by driving rollers or different if only the partitions without free outlet close behind the opposite Trimming shears is arranged.

- patent claims -

1 0 9 8 3 2/0 S 3 5

Claims (8)

Management company 667 St. Ingbert, Ί8. March 68 Moeller & Neumann general partnership t, March 18 PATENT CLAIMS 1.) Shear line for trimming and dividing sheet metal, in particular Heavy plates, consisting of long-knife trimming shears set up opposite one another on both sides of the roller table and a downstream dividing shear, wherein the sheet feed can be actuated by at least one dependent on the blade movements of the continuously driven trimming shears Driving roller pair takes place at intervals, characterized in that the dividing shear (T) is a so-called roll-cutting shear with a rocking movement executing curved knife and is set up at such a short distance behind the trimming shears (D) that the sheets without free outlet are subdivided in the clamping by the one or more pairs of driving rollers (4, 6) whose feed interval exceeds a desired sheet metal length can be shortened independently of the drive of the trimming shears. 2.) scissors line according to claim 1, characterized by a control with one that is switched on by an initial crop cut of the dividing scissors (T) Device (10) for generating a first length proportional to the sheet metal length then advanced in one or more intervals Signals, a preselector (62) for storing a second signal (L ^) proportional to the desired partial length and a first comparison device (60) to generate a pulse to stop the pair of driving rollers (4, 6) when comparing zero, regardless of the drive of the trimming shears. 3.) Control in particular according to claim 2 for pruning shears with transverse knives attached to the infeed side of the hemming knives for separating the hemming strips, characterized by a device for setting a shortened, last sheet feed (^ V2) exceeding at least the sheet thickness (d), depending on the given Finished length (L> _F ) of the sheet (83) while shortening the previous feed gap (V.) to a penultimate .'il front shoe ( & V ₁ ) also exceeding the sheet thickness (d). 10 9 8 3 2 Λ0.5 3 5 4.) Control according to claim 3, characterized by a difference device for determining the difference between the second signal (1- · ρ) and the first signal (L _e ff). a second comparison device (63) for determining whether the condition ^L F - ^L eff> V <V ₊ d is fulfilled, where V is the set feed interval and d is the presettable sheet thickness, and a changeover switch (67) for temporary disconnection Control variable of the full feed interval (V) from the Vo: · feed control and switching on a shortened partial feed (jJA V,) corresponding, in a preselector (79) set control variable that is greater than the Sheet thickness (d), the temporary switchover being carried out by a pulse from the second comparison device (63) if this is done it is found that ^L F - ^L eff 5.) Control according to claim 2 or 3, characterized in that the pulses for stopping the or pairs of driving rollers by zero comparison in the first comparison device (60) a cutting stroke of the dividing scissors (T) itself actively trigger and the drive of the driving roller pair or pairs during the Working cycle of the dividing scissors is electrically viewed. 6.) Control according to claim 5, characterized in that the pulses for Triggering a cutting stroke of the dividing scissors (T) from the first comparison device (60) as far before the zero comparison as taking into account the acceleration time for starting the scissors up to the start of cutting, an overlap of sheet feed and Knife movement possible isf. 7.) Control according to claim 5, characterized by a device for Triggering of the glass feed · depending on the movement of the 109832/0535 Cutting knife of the dividing scissors (T) before stopping the cutting drive at the time when the moving cutting knife is also by one Sheet metal of maximum thickness is certainly free. 8.) Control according to claim 7 for a partial scissors with two against each other offset crank drive unit for the moving cutting knife, characterized by a contactor that can be adjusted via the crank path of a crank to trigger the sheet feed. 109832/0535 1* Blank page