DE1166069B - Cigarette rod machine or the like. - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Boarding school Class: A 24 c

German class: 79 b -13/10

Number: 1166 069

File number: M 49483 III / 79 b

Filing date: June 28, 1961

Opening day: March 19, 1964

The invention relates to a cigarette rod machine od. The like. In which on an air-permeable Conveyor a continuous stream of tobacco is formed.

It has already been proposed to use an air permeability testing device in such machines to detect differences in mass per unit length of the tobacco stream and a control device operated by the test device for changing the mass per unit length of the tobacco stream.

The invention is based on such a machine; however, there is the air permeability and the density The tobacco flow for a given tobacco will be inversely proportional to the more tobacco in a given one Volume is compressed, the lower the air permeability through the tobacco flow be. In order to exploit this phenomenon, according to the invention, the test device works for the air permeability with compressed air, and there is a pump available, the air through the tobacco stream leads through into a delimited space of constant volume, which is between a trough, through which the format tape pulls the tobacco stream, and one opposite it Part, such as a known press shoe or a tongue, is formed. Here are during of passing the air through a constant volume of tobacco changes in mass per unit length directly affect the flow resistance or the air permeability.

The enclosed space is preferably downstream of the control device, the pump is a positive one acting pressure pump, such as a vane pump with radially slidable vanes with an opening in the wall of the part opposite the trough, and differences in air pressure at said opening are transferred to an intermediate chamber to absorb the pressure, that arises in the confined space, and the subdued changes in this pressure are one pressure-sensitive device, such as membrane cans or flexible bellows, can be fed through the control device for long-term changes in the amount of tobacco in operated by the current.

The control device can have a reversible electric motor, by means of which the known removal device is drivable in one direction or the other to increase the amount of excess tobacco removed from the tobacco stream change, the motor od through the membrane can cigarette rod machine.

Applicant:

Molins Machine Company Limited, London

Representative:

E. Riebensahm, lawyer,
Karlsruhe, Lammstr. 22nd

Named as inventor:
Desmond Walter Molins,
GFW Powell,

F. Pocock, London

Claimed priority:

Great Britain June 29, 1960 (No. 22 772)

or the bellows can be controllable so that it drives the removal device until the diaphragm can or the bellows detect an air pressure within a given compressed air range that is the desired Indicates mass per unit length of the tobacco stream.

The air pressure from the intermediate chamber is fed to the bellows and they control an electronic one Circuit that controls the reversible motor with the bellows set to Contacts close at the lower or upper limits of the compressed air range, the electronic The circuit is unbalanced in one direction and the motor is rotating in the opposite direction leaves when both contacts are closed.

In the drawings, exemplary embodiments are shown, namely shows

F i g. 1 a part of a cigarette rod machine in a schematic representation,

F i g. 2 an enlarged individual representation of a part according to FIG. 1,

F i g. 3 shows an enlarged individual illustration of another part according to FIG. 1,

F i g. 4 shows a part according to FIG. 3 in a modified version,

F i g. 5 shows a section along line 5-5 in FIG. 3,

F i g. 6 shows a section along line 6-6 in FIG. 3,

F i g. 7 shows an electrical circuit arrangement according to FIG. 1,

409 539/96

F i g. Figure 8 is a front view with parts partially cut away and partially removed modified embodiment according to FIG. 1,

F i g. 9 shows a section along line 9-9 in FIG. 8 on a larger scale and

F i g. 10 shows an electrical circuit arrangement according to FIG. 8th.

In the cigarette machine according to FIG. 1, a continuous stream of tobacco is formed and held in a known manner by suction on the underside of a perforated conveyor belt made of metal. A narrow channel 1 extends up to the perforated endless conveyor belt 2, which circulates in the direction of the arrow through the upper part of the channel. A suction chamber 3 is located above and to the left of the lower run of the conveyor belt 2; Air is sucked out of the chamber 3 through a pipe 4 by means of a fan (not shown). The arrangement is such that a stream of air flows up through the duct 1 at high speed and is drawn through the perforated conveyor belt. Cut tobacco is fed into the channel so that it is guided backwards against the conveyor belt, where it builds up into a filling rod which is held on the conveyor belt by suction. The arrangements for promoting tobacco are suggested elsewhere.

Outside of channel 1, i. H. according to FIG. 1 on its left, is a conventional tapping device shown, which consists of a pair of rotating cutter disks 5, which below the Conveyor belt are arranged and remove excess tobacco from the filling rod.

These cutter disks 5, the position of which is indicated schematically in FIG. 1 by dash-dotted lines is, lie side by side, so that their opposite edges the filling strand in one Cut the desired distance from the conveyor belt 1. The arrangement is similar already described (German Auslegeschrift 1109 071).

The cutter disks 5 are shown in FIG. 1 also shown schematically in full lines, to show the manner in which, in accordance with the invention, the position of the disks opposite the conveyor belt 2 is changed. The solid line representation of the disks 5 in F i g. 1 is not intended to represent its position in relation to the conveyor belt, but merely reproduces part of the according to the invention.

Inside the suction chamber 3 and immediately above the conveyor belt 1 is directly to the right of the Disks 5 according to FIG. 1 a small chamber 6 is arranged. This chamber 6 is open on the underside, so that the air can enter them through the perforations of the conveyor belt 2. A small pipe 7 leads from the chamber 6 into the suction pipe 4.

Another pipe 8 leads from the chamber 6 to one formed from a plurality of flexible pressure cells 9 Bellows, so that the pressure within the bellows corresponds to that of the chamber 6.

A rod 10 is attached to the lower end face of the bellows. The bellows is attached and arranged in such a way that that its lower end face and with it the rod 10 as a function of the pressure changes of the bellows can be moved up and down. The rod 10 forms the input of a hydraulic one Amplifier, which is shown as block 11. A crank disk 14 is located at the output of the amplifier arranged, which is rotated in response to the movement of the rod 10; the connecting rod 14 moves a tab 13 up or down. The tab 13 is pivotable at the right end of one Lever 12 suspended.

The lever 12 has a central slot 15 which receives a bolt 16 on one of the cutter disks 5 receiving housing is attached. A tension spring 27 pulls the housing upwards.

At the end of the lever 12 opposite the tab 13 is a one equipped with a threaded hole Sliding block 18 arranged; the threaded hole is in engagement with a screw 19, which is rotated in one direction or the other by a reversible electric motor 20.

The device described above is detailed apart from the control of the electric motor 20 already proposed.

According to FIGS. 1 and 3, the perforated conveyor belt 2 runs over at the left and right ends arranged rollers, of which the left roller 30 is shown. Below and to the right of roll 30 the format tape 31 is shown, which runs counterclockwise over the roller 32 and enters the format tray 33 shown in FIG. 3 is shown partially in longitudinal section. Right next to the roller 32 runs a paper tape 34 over two rollers 35, 35 counterclockwise in FIG the trough 33 above the format belt 31. The edges of the paper tape 34 are when entering the trough 33 is bent into a U-shaped cross section; the edges are denoted by 36.

The above-described, partly known, partly proposed details are necessary for understanding. however, do not belong to the invention.

In addition to the left lower quadrant of the roller 30, a pressure shoe 37 is arranged, which is shown in FIG. 3 is shown in section. This figure also shows the length of the trough 33 versus the length of the shoe 37. The right end of the shoe 37 is bent slightly upwards in order to remove the tobacco from the conveyor belt 2 on the roller 30. The cross-sectional shape of the shoe 37 and the change in the cross-sectional shape in the longitudinal direction of the shoe are shown in FIGS. 3 and 5. The entry end 37 α of the shoe is rectangular and continues in a curved part 37 b . Immediately on the left of the pressure shoe 37 is a tongue 38, the cross-section of which is shown in FIGS. 3 and 6 can be seen. The F i g. 3 shows the length of the trough 33 in relation to the length of the tongue 8. FIG. 5 and 6 show the trough 33 as an oblique U-shaped cross-section in this area, with a small gap between each side of the shoe 37 and the tongue 38 and the walls of the trough 33 through which the edges of the format tape 31 and the paper tape 34 go through.

The tobacco stream is transferred from the conveyor belt 2 below the roller 3 onto the paper belt, whereby the suction air disengages from the stream of tobacco.

The paper tape 34 with the stream of tobacco lying on it is by means of the format tape 31 under the pressure shoe 37 and the tongue 38 pulled through. The tobacco flow is at least half that its final compaction in the wrapped cord when it is compressed under the shoe

37 reaches, and laterally further compacted in the passage below the shoe 37 and then laterally compacted still further while under tongue 38, to a degree that is slightly larger than what is required in the wrapped cigarette rod; the paper strip will then folded by folding members over the stream of tobacco in the usual way; is part of these folding organs designated by 39.

Instead of a testing device that works with beta rays that has been proposed elsewhere, see FIG the invention uses the arrangement described below. Air is drawn in from the atmosphere sucked a vane pump 40 and passed through the tube 41 to the tongue 38 just before its right end. The end of the tube 41 is beveled where it enters the tongue so that the tobacco is not sharp Edge is offered that could affect the flow of tobacco. The pressure in pipe 41 is in communication with the interiors of the two chambers 42 and 43 via a pipe 44 into which an intermediate chamber 45 is switched on with a throttled or merely damping input 46.

The chamber 42 carries a flexible membrane 47 on its right side wall, while the chamber 43 is provided with a similar membrane 48. The membrane 47 has an electrical in its center Contact 49, which can come into engagement with contacts 50 and 51 arranged on the side of it. These contacts are at a distance from the contact 49, so that when a certain pressure change occurs in the tube 41 the contact 49 comes into contact with one of the two contacts 50 or 51, depending depending on whether it is an increase or decrease in pressure. The contacts are connected to an electrical circuit shown as box 52 as it is similar elsewhere is suggested. The arrangement is such that the reversible motor 20 rotates in one direction is when the contact 50 contacts the contact 49, and rotated in the other direction when the Contact 51 touches contact 59. The motor continues to rotate until the contact pair is separated again will. Circuit 52 is shown in FIG. 7 shown in detail.

The membrane 48 also carries a similar contact 53, and there is one on each side of that contact further contact 54 and 55 are provided. These three contacts are also connected to circuit 52 in Connection, and when the contact 53 closes with the contact 54 or the contact 55 is a Relay energized, which stops the motor 20. The contacts 54 and 55 are designed so that a stronger Pressure fluctuation in tube 41 is required before contact 53 with either contact 54 or the contact 55 comes into contact as it does to contact the contact 54 with the contact 50 or 51 is required.

According to FIG. 7, a direct current is applied to the armature 249 of the motor 20 is given by the rectifier 278, and the current direction is controlled by two magnetically operated switches 292 and 293 fed by rectifiers 298 and 299; Each of these switches has two switching arms 294, 295 and 296, 297. When the contact moves 49 for contact with the contact 50 or 51 becomes a circuit to one of the switches 292 and 293 closed, and the corresponding relay gives current to the armature 249 and the field 250, and the Motor rotates in one direction or the other, depending on the circuit involved, and raises or lowers the cutting knife 5. Instead of this or in addition, the motor 20 can be used for this purpose adjust a variator to change the speed of the tobacco conveyor.

By means of the relay switch 300 it is achieved that the line to contact 49 is interrupted, when contact 53 touches either contact 54 or 55.

The pump 40 is shown in detail in section in FIG. 2 shown. It is a well-known vane pump, which consists of a chamber 56 with an inlet 57 and an outlet 58. A rotor 59 is eccentric arranged to the center of the chamber 56 and carries four wings 60 which are free in the radial direction under the action of centrifugal force when the rotor 59 rotates in this slide and on the inner wall the chamber 56 rest. When each pair of wings 60 slides past the inlet 57, the Air trapped between them and transported to outlet 58 and under pressure into that outlet entered as the vanes enter the rotor upon contact with the top of chamber 56.

The operation of the device is as follows:

When the tobacco stream lying on the conveyor belt 2 is passed under the chamber 6, is Air is sucked through the filling string and the conveyor belt 2 into the chamber 6 and occurs through the pipe 7 Reason of suction. The air pressure prevailing in the chamber 6 at any given moment depends So from the amount of tobacco that is located in the longitudinal direction of the filling rod below the chamber 6; thus the pressure in the chamber is a measure of the air permeability of this length of filling strand and thus a measure of the amount of tobacco contained in this length. The fluctuating pressure in the chamber 6 is thus a measure of the uniformity of the tobacco stream passing under the chamber 6; this pressure is transmitted to the bellows 9 via the tube 8 and the rod 10 moves upwards at a low pressure in the bellows 9 and indicates that below the chamber 6 a Excess tobacco is located; the rod 10 is moved down when there is high pressure in the bellows what is an indication that there is not enough tobacco below the chamber 6 prevails.

The arrangement is made so that the filling rod has an excess of tobacco at all points along its length which has to be removed by the cutting device 5. If the Moving rod 10 downward, as previously shown, the hydraulic booster 11 acts accordingly on the tab 13 and moves the right end of the lever 12 and the cutting knife 5 to at the top, so that more tobacco is removed from the length of the filler rod. That way will in the case of determinations of changes in the evenness of the filling strand, the acceptance process accordingly controlled to correct or at least reduce these changes. This Part of the device is the subject of an older proposal.

However, there can be long lasting changes in the average weight of the filler when exited the cutting device 5 are present, for example by changing the moisture content

of tobacco or by changing the tobacco itself. Therefore, the position of the cutting device 5 relative to the conveyor belt 2 is additionally changed by the left end of the lever 12, which is raised or lowered by rotating the motor 20 in one direction or the other depending on the air pressure prevailing in the tube 41.

This air pressure is the pressure fluctuation caused by the tobacco in the tongue 38, since the format tape is in contact with the trough 33 and all of the air is forced to flow through the tobacco and to step outside from the tongue. The tongue 30 and the adjacent part of the trough 33 form walls which represent a guide through which the unwound tobacco stream is guided along its length, the walls closing around almost the entire surface of the tobacco stream. The air forced into the filler rod in the tongue 38 exits into the atmosphere on the sides of the tongue and pressure shoe 37; however, the extent to which the air can escape depends on the amount of tobacco that is blocking the airway. Since this exit path is of constant volume because the tongue and pressure shoe and trough 33 are rigidly arranged, a dense tobacco stream length blocks the exit path more and the pressure in the tube 41 rises and exerts a larger surge through the larger one in the constant volume compacted amount of tobacco. Similarly, a lower pressure is created in the tube 41 when a lighter length of fill flow passes under the tongue. In this way, a different air pressure is produced in the pipe 41 , which is an indication of the changes in the mass per unit length of the trimmed filling strand. The mean value of this pressure is 630 mm water column. It has been found that there is a very high correlation between this air pressure and the mass per unit length of the filling strand. The intermediate chamber 45 compensates for brief changes in this air pressure and generates an air pressure which is an indication of the average tobacco content in a filling rod length corresponding to 25 cigarettes. A corresponding value between 25 and 50 cigarettes can also be selected.

When the air pressure drops to such an extent that the cord is 1% too light, the diaphragm 47 with the contact 49 is moved to the left and a circuit is closed through the contact 50 , which starts the motor 20 to the cutting device 5 to move downwards. The motor 20 continues to run until the membrane 47 is under the action of an air pressure which indicates that the filling strand is no longer 1% too light. If the filling strand is more than 1% too heavy, the contacts 49 and 51 come into contact and the motor 20 rotates in the opposite direction until the filling strand is less than 1% too heavy; Due to the compensating effect of the chamber and the inertia of the system, the motor is stopped after some time, regardless of the direction of rotation, and the filling strand, instead of being 1% too heavy or 1% too light at the limit, becomes the exact nature exhibit.

However, there are occasions where a signal is given for excessive heaviness or oversized light and where it is not desired to change the position of the cutting device 5, for example when starting or stopping the machine. If the signal reads more than 5% too heavy, contacts 53 and 55 close and stop the rotation of motor 20, and if the read is more than 5% too light, contacts 53 and 54 close and the circuit is closed of the motor 20 is again interrupted.

As previously suggested, the motor 20 can additionally be used to change the operating speed of the hopper, not shown, to change the conveying speed of the tobacco to form the tobacco stream, or the hopper can be controlled in this way instead of controlling the position of the cutting device 5.

The F i g. 4 shows a modified embodiment in which the tube 41 is received in the pressure shoe 37 instead of in the tongue 38. In this case, a narrow gap 61 is provided between the shoe and the tongue for the entry of air from the tobacco, otherwise the design and mode of operation are as previously described. In this case, the mean value of the pressure prevailing in the pipe 41 is 400 to 450 mm water column.

The F i g. 8, 9 and 10 show a modified display device 152 in place of the chambers 42 and 43. In this arrangement, no device which performs a function corresponding to the chamber 43 is provided. In Fig. 8, an electrical circuit is provided in addition to the circle 152 as box 153 , while the circle of box 153 is shown in more detail in FIG. 10 is shown. The F i g. 9 is a section along line 9-9 in FIG. 8 on an enlarged scale.

According to FIG. 8, the tube 12 leads the air pressure from the equalization chamber 45 to two tubes 154 and 155, which transmit the air pressure to two spring boxes or elastic bellows 156 and 155 , which are connected to the cover plate 158 of the device 152 . The lower surfaces of the bellows 156 and 157 carry electrical contacts 159 and 160 which are in communication with fixed contacts 161 and 162 which are arranged on a plate 163 which is adjustable in the vertical direction by the distance between the contacts of the bellows and to change the fixed contacts. The vertical adjustment is effected by the following arrangement, as is also shown in FIG. 9 shows. The ends of the plate 163 carry two pillars 164 and 165 attached to them, which protrude through the cover plate 158 and are connected at their upper ends by a bridge 166 . A threaded bolt 167 is only rotatably received in the bridge 166 and carries a corrugated button 168 and a graduated scale 169. The bolt 167 is screwed at its lower end into a nut 170 which is fastened to the cover plate 158. Upon rotation of the knob 168 raises or that is, the bridge 166 and the columns 164 and 165, and with them lowers the plate 163 with the contacts 161 and 162. Referring to FIG. 5, the contacts are formed in the form of cantilever springs 161 and 162 which are fastened with one end in insulating pieces 170 and 172. At their other ends, the springs 161 and 162 are individually adjustable to adjust the distance between each spring and the associated contact of a

To change bellows. At the left end of the plate 163 two blocks 173 and 174 are attached, which the Carry eccentrics 175 and 176. The free end of the spring 162 is held under the eccentric 176, when it is rotated, the gap between this spring and the contact 160 is changed. On the same The spring 161, the eccentric 175 and the contact 161 work in this way. that the contact 160 the spring 162 at a certain increase in the air pressure in the bellows touches, above the pressure at which the contact

159 would touch the spring 161. Turning the knob 168 adjusts the air pressure accordingly the tobacco mass per unit length set within the precise range, namely with the contacts 159 and 161. Electrical lines 177 and 178 lead from springs 161 and 162 to the Circle 153, and an electrical line 179 leads from contacts 159 and 160 also to the District 153.

The device 153 is set so that in the presence of air pressure in the bellows 156 and 157, which shows too little tobacco when passing under the tongue 38 or the shoe 37, all contacts are open, while at an air pressure which shows the exact amount of tobacco, namely within l% too heavy and 1% too light compared to the average weight, contacts 159 and 160 closed and if there is too much tobacco the contacts

160 and 162 are also closed. According to FIG. 8, the following arrangement is made to achieve the To hold plate 163 in all positions exactly in the horizontal position. The plate 163 is rigid on the fixed upper end of a rigid tube 179, which is between three pairs of ball bearings 180, of which only two pairs are shown. Each pair of ball bearings is received in a housing 181 that is attached to attached to the sides of the device 152. The in F i g. 10 circuit shown is a relay switch with two transistors and is in the drawing with the contacts 159 and 161 and 160 and 162 of the display device 152 and includes three contacts 149, 150 and 151 connected to circle 152 in a manner similar to that of the contacts 49, 50 and 51 of the device described above.

Terminals 182 and 183 are connected to and supply a 300VoIt AC power source a direct current of approximately 28 volts by means of the rectifier 184 and the filter device 185. The current is given through the bases of the two transistors 186 and 187 to a network that is closed when Contacts 161 and 159 and open contacts 160 and 162 is symmetrical to excitation coils 188 and 189 of a quick closing relay 190 to keep in balance. Contacts 149, 150 and 151 are parts of the relay 190 and are open in the equilibrium position. When contacts 160 and 162 are closed, an additional resistor 191 is placed in parallel with resistor 192, so that a higher current flows into transistor 187 and the relay is out of balance, whereby contacts 149 and 151 are closed. When the two sets of contacts 159 and 161 and 160, 162 are open, the relay 190 is in the opposite sense out of equilibrium, since there is no current flows into transistor 181, thereby closing contacts 15 and 159. By opening and closing the contacts 149 and 150 and 151, the circuit 52 is controlled in the same way as through contacts 49, 50 and 51 of the embodiment described above. In this modified embodiment relay switch 300 of circuit 52 is omitted.

The modified device works as follows: The eccentrics 175 and 176 are set so that the exact pressure difference prevails between the closing contacts 159, 161 and 160, 162, corresponding to the exact range of the mass per unit length of the tobacco filler rod, namely between ± 1 ^fl / o the average weight. The button 169 is then set to a pressure between that at which the contacts 159, 161 and 160, 162 close to match the desired average weight of the tobacco stream. If the tobacco flow is then more than l% too light, all contacts 159, 161, 160 and 162 are open, contacts 149 and 150 are closed, and the motor 20 rotates and moves the cutting device 5 in the sense of less tobacco removal from the stream of tobacco. When the tobacco stream is within the exact weight range, the bellows 156 moves the contact 159 into contact with the contact 161 and the contacts 149, 150 and 151 are all open and the motor 20 is stopped and the cutter 5 remains in the same position . When the tobacco flow becomes more than 1% too heavy, the bellows 157 brings the contact 160 into contact with the contact 162, and the contact 149 contacts the contact 151, and the motor 20 rotates to drive the cutter for greater tobacco removal to move the tobacco stream.

Claims (6)

Patent claims: 1. Cigarette rod machine or the like with an air-permeable conveying device for the tobacco stream, also an air permeability testing device for determining differences in mass per unit length of the tobacco stream and one through the testing device actuated control device for changing the mass per unit length of the tobacco stream, characterized in that the test device for air permeability with compressed air operates and has a pump (59, 60), the air through the tobacco stream in a delimited space of constant volume leads between a trough (33), through which the format tape (31) pulls the tobacco stream, and one opposite it Part, such as a known press shoe (37) or a tongue (38) formed is. 2. Machine according to claim 1, characterized in that the delimited space is downstream the control device, the pump is a positive-acting pressure pump (59, 60), for example is a vane pump with radially slidable vanes with an opening in the wall of the the part (37, 38) opposite the trough is connected and differences in air pressure at said opening are transmitted to an intermediate chamber (45) for absorbing the pressure in the surrounding 409 539/96 Bounded space is created, and the muted changes of this pressure become a pressure-sensitive one Device, such as membrane boxes (42, 43) or elastic bellows (156, 157), can be supplied are, through which the control device for changes over a long period of time Amount of tobacco in the stream is operated. 3. Machine according to claim 2, characterized in that the control device is a known one Having removal device and a reversible electric motor through which the removal device can be driven in one direction or the other to the amount of excess tobacco removed from the tobacco stream to change, the motor through the diaphragm box (42, 43) or bellows (156,157) so it is controllable that it drives the removal device until the diaphragm box or the bellows are inside of a given compressed air range, determine an air pressure that has the desired mass per unit length of the tobacco stream. 4. Machine according to claim 3, characterized in that the bellows (156, 157) of the Air pressure is supplied from the intermediate chamber (45) and they form an electronic circuit (186,187) which controls the reversible motor (20), with the bellows (156,157) are set so that the contacts (159,161; 160,162) at the lower and upper limits of the compressed air area, the electronic circuit (186,187) in one direction is unbalanced and causes the motor to rotate in one direction when the contacts (159,161; 160,162) are open and balanced and stop the motor if only the contacts (159,161) are closed and the circuit is unbalanced in the other direction and lets the motor rotate in the opposite direction when both contacts (159, 161; 160,162) are closed. 5. Machine according to claim 4, characterized in that the adjustable contacts (161,162) are contact springs, the free ends of which are against a rotating eccentric (175, 176), which, as it rotates, removes them from the contact (159, 160) to the Bellows (156,157) changes so that the difference between the air pressure at which a contact pair (159,161) is closed, and the air pressure at which the other contact pair (160, 162) is closed, is adjustable. 6. Machine according to claim 5, characterized in that the eccentric (175,176) and the contact springs are carried by a member (plate 163) which allows simultaneous adjustment the contact springs (161,162) opposite the contacts (159,160) on the bellows (156,157) allows, so that the air pressure, which is between that at which the two pairs of contacts are closed, is adjustable. For this purpose 2 sheets of drawings 409 539/96 3.64 © Bundesdruckerei Berlin