DE1535026A1 - Winding machine, in particular a roving machine, flyer or the like. - Google Patents

Description

1535023

Patent application

Applicant: Whitin Machine Works,

Whitinsville, Massachusetts V. St. A.

Winding machine, in particular a roving machine, flyer or the like.

The invention relates to machines in which one of Feed device withdrawn fibrous material is wound on a spool.

Such machines, e.g. B, such roving machines known and described, for example, in U.S. Patent 2,003,362 to Hendrickson, which patent is assigned to the assignee of the The present application has been assigned »These machines represented a considerable technical at the time of their appearance Progress, but further improvement of these machines is desired.

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For example, there is work involved in the known machines the contact wave is associated with a strong noise, since the contact wave suddenly in singriff with a very fast rotating '.VeIIe (the upper conical shaft) georacht and after only half a turn you suddenly have to brake, with strong noises and shocks with the skipping gear, with the contact cams, with the -Vickel construction nuts and caused by the contact wave.

Furthermore, in the known machines there is the risk that the bobbin bank in the "idle" period in which the double bevel gears be shifted, exceed their limits »

In the known machines, the front roller speed must also be used should be limited to about 300 rpm, since at higher speeds the "jump gearwheel" does not work properly meshes with the upper conical bevel gear »

Furthermore, the known machines cannot be safely braked in all working positions of the moving bobbin bank »

The present invention is based on the object of eliminating the listed disadvantages of the known machines

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In particular, the invention is based on the object Damping effect of a compressible fluid during movement of the speaker for the conical belt of conical pulleys «Nspunutsen, in order to reduce noise and shocks to a minimum ·

The object of the invention is to ensure that the bobbin bank is held firmly at the reversal point of its movement easier to set the "uninspired" period in the Reversal is eliminated

Furthermore, the invention is intended to provide a lap build-up mechanism be ground, which operates independently of the machine speed, so that the front roller speeds can be considerably higher than 300 rpm.

Furthermore, the machine should be moved from every working position Spool bank can be safely braked from.

Another object of the invention is to provide one electrical switching arrangement, which is able to control the execution of a first, • wide and third work process. These Operations can be, for example, the implementation of a relative transverse displacement of the feed device and Coil in a first direction, performing a relative

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ORIGINAL INSPECTED

Transverse displacement of the feed device and spool in a second direction opposite to the first and the implementation of gradual adjustments of the handlebar for the conical belt at the end of each transverse shift.

Another object of the invention is to provide an electrical To create a control circuit for a roving machine in which the damping effect of a compressible fluid is used is used to reduce noise and shocks associated with the movement of the handlebar "

Another object of the invention is to provide a specific winding machine and a specific electrical controller with each other to combine, whereby the aforementioned disadvantages of the known machines are eliminated.

The solution to some of these objects of the invention is achieved in a line for pulling fibrous material from a feed device and for winding this material on a reel, in that a drive device for producing a relative rotary movement between feed device and reel as well as a relative transverse displacement between these in sieving their axes of rotation and also a control device are provided which at least limit one of the Sr :; λ er ,, ^ a; Rotated '; speed, (b) <, excessive speed, and (c) length of the displacement to values vr _y

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ν and 1 is suitable. The control device preferably comprises a pneumatic piston-cylinder device, means for the intermittent actuation of the piston-cylinder device providing an output and means which couple this output to the drive device in such a way that at least one of the is changed by the control device limited sizes.

Further objects of the invention are in a machine for performing first, second and third operations solved in that a first and a second üelaisspule, a first, second, third and fourth contact pair, which controlled by the first and second coils, and a control relay coil provided. The first pair of contacts can alternatively take a first and a second position and is to take the first position by excitation of the first coil and caused to assume the second position by energizing the second coil. The second pair of contacts can alternatively assume a third and a fourth position, the third position when the first coil and assumes the fourth position when the second coil is energized. The third pair of contacts can alternatively be a fifth and a sixth Take up position and take the fifth position when the second coil is energized · The fourth pair of contacts can be a seventh and occupy an eighth position and take the seventh position when the first coil is excited and the eighth position when the

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«A \ J · ^

the second 3-coil. It is provided for all contact pairs that they do not change their positions when both the first and second coil are de-energized. In its first position, the first pair of contacts causes the first operation to be carried out; the second pair of contacts in its fourth position causes the second operation to be carried out; the third pair of contacts causes the control relay coil in its fifth position and the fourth pair of contacts in its eighth position. A fifth pair of contacts is also provided, which can alternatively assume a ninth and tenth position and which assumes the ninth position when the control relay coil is energized and the tenth position when the control relay coil is switched off. Sine of the new and tenth positions causes the third working process to be carried out.

Further objects of the invention are achieved through the interaction of the features described above.

The invention is explained in more detail below in an exemplary embodiment with reference to the drawing, in which:

Fig. 1 partly schematically, partly in section, the device according to the invention;

Fig. 2 is an enlarged perspective view of a 'file of the device according to Fig. 1 and

Fig. 3 shows an electrical circuit arrangement for the Vorrich

device according to Fig. 1. 009815 / U98

Fig. 1 shows a drive device 10, which has suitable Gear connections 11, 12 is connected to an upper, conical pulley 14 and a wing 16 and this with constant rotation aiii en drives.

The bit above conical pulley 14 is connected to a lower conical pulley 18 via a conical belt 20, which is almost pulled over these two, so that when the upper pulley 14 is rotated in the direction of the arrow, the lower pulley 18 rotates in the arrow direction shown there.

SIt upper conical pulley 14 is either linear (like shown) or nonlinearly tapered in such a way that their diameter perpendicular to the axis of rotation on the base 22 (in Fig. 1 the left Base of the truncated cone) is larger than its diameter at the base: 24 ·. The lower conical pulley is similar tapered either linearly (as shown) or nonlinearly and has a large base 26 and a small base 27. In the However, the large Bs & s lie on the right and lower pulley the small base on the left.

A belt guide or belt guide 28 comprises a section of the strap 20 and serves to hold the belts along the acnsen of the

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- 8 -ORIGINAL INSPECTED

upper and lower pulleys 14 ·, 18 to move. The conical Pulleys 14, 18 and the belt 20 form a variable mechanical translation. If, for example, the belt is shifted to the left in the illustration according to FIG. 1, the speed of the lower pulley 18 increases, while with a shift of the belt 20 to the right, the speed the lower pulley 18 decreases.

For example, when winding roving, it is generally desirable to move the belt to the right in FIG. 1 following each relative displacement of the wing 16 and the bobbin 50 to be wound. As already mentioned, the wing 16 is driven by the drive device 10 at a constant speed. The spool 30, which is connected to the lower conical pulley 18 via suitable drives 32, 33, rotates in the same direction as the vanes 16 but more slowly than de: - vanes 16, so the feed device and the spool rotate with it As the thickness of the winding increases, the angular velocity of the winding would be extremely high if the rotation speed of the reel were not reduced with each successive transverse displacement by the belt 20 moving to the right. In order to obtain the tapering form of the '.'Zickel shown ax at t, proceed further to ~ 3'.ve ~. : i <-. 3 '; cr: die Zejire 1 r-r'r.er;'e; ^ n '.vif ei zanderiolrende :: ^ uervo: ^': i '::.;:; R - / r. «

The gill link 28 is provided with a rack 34 which is adjustable via a gear mechanism 36, which in turn via a pawl 38 under control by the Piston rod 40 of a piston-cylinder device 42 is driven will.

Upon movement of the piston 43 (.Fig. 2) in FIG on the right and in Fig. 2 in the direction of the lower arrow, the gear transmission 36 is in such a way via the ratchet assembly 58 actuated that the rack 34 and thus the belt link 28 be shifted to the right in Fig. 1. This is what makes it happen Transmission ratio of the variable mechanical formed by the conical pulleys 14, 18 and the belt 20 "Translation changed. The directions of rotation of the gears of the gear transmission 36 are indicated by corresponding arrows in - ^ ig. 2 displayed. Movement of the piston 43 in the opposite direction, i.e. to the left in FIG. 1, affects the Position of the belt 20 is not off because the pawl 38 with such a movement of the piston 43 rotates in freewheeling.

Fig. 1 also shows a compressed air supply line 44 and an outlet line 46, which via a reversing valve 48 to the piston-cylinder device 42 are connected. The reversing valve 48 is activated by an electromagnet 50 against the force of a return spring 54 actuated. When the electromagnet 50 is energized, it increases

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the valve 48 is in the position shown, in which the compressed air supply line 44 via a valve channel 45 and a line 52 with the left end of the piston-cylinder device 42 is connected, so that the piston 43 is shifted to the right and has a switching function is carried out, d. H. a displacement of the belt link 28. The other end of the cylinder is via a line 58 and a valve channel 47 connected to the outlet line 46. If the valve 48 with the solenoid 50 de-energized through the spring 54 is moved to the left, then the compressed air line 44 connected via a valve channel 56 and the line 58 to the right end of the piston-cylinder arrangement 42, so that the piston 43 is displaced to the left. In this In position, the left end of the cylinder is connected to the outlet line 46 via a valve channel 60.

Flow control valves 61, 61 '(Fig. 2) control the speed of the piston 43 and prevent shock loads.

A compressed air monitor 63 shuts down the machine if the air pressure in the network falls below a proper functioning of the Winding device ensuring pressure drops that usual is about 2.8 kp / cm.

The switching electromagnet 50 is, as can be seen from Fig. 3, when the contacts CR-1 are closed, the contacts CR-1 and the solenoid 50 in series between lines 62,64 to which a DC voltage is applied.

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The contact · .CH-1 is closed by switching on a winding structure control relay CR. Provision can be made to have the control relay at either end of the relative transverse displacement of feeder or vane 16 and coil 30 is energized, but preferably it is provided that the control relay CR is energized at each end of such relative movement of vane 16 and coil 30 * For this reason the control relay CR is normally via a pair open contact LR-3 connected to line 66 and a pair of normally closed contacts LR-4 connected to line 68

The lines 66 and 68 lie between the control voltage lines 62 and 64 and each serve to feed the relay coil LR-R and the reset coil LH-L of a pulse relay 74 · The relay coil LR-R is energized after closing a first limit switch 76 of a lap build-up switch 77, while the reset coil LR-L is excited after a second limit switch 78 of the switch 77 is closed

The first and second limit switches 76 and 78 turn on the opposite ends of the relative transverse displacement of vane 16 and coil 30 closed, which is achieved by making contact between a first and a second contact cam 80 and 82 takes place with a third contact cam 84 (Fig. 1). The contact cams 80 and 82 are each on winding assembly nuts 86

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BAD ORIiSiNAL

and 88 attached, which are screwed onto a rotatable spindle 90 are, which on its lower part 92 and a higher part 94 each has opposite threads and on its uppermost section 90 * is square in cross section, so that a gear mechanism 130 can act on it. The nuts 86, 88, the screw 90 and the contact cams 80, 82 are attached to a bearing part 96, which is rigid with a coil bank 98 is connected, on which the coil 30 is also arranged is. This bobbin bank 98 can be moved up and down in such a way that that a relative transverse displacement of length 1 and speed ν between wing 16 and coil 30 is achieved will. The drive for this transverse displacement includes a reel bench lift 100 with rack 101, which is in engagement with the gear drive 102 connected to the shaft 104. The wave 104 is driven via a reversible clutch mechanism 105 with clutches 106 and 107, each via one of the wheels of the bevel gear pair 110, 114 are driven «The bevel gears 110 and 114 rotate in opposite directions Directions as they are coaxially arranged and driven by a bevel gear 112 which is constantly in mesh with the Bevel gears 110, 114 and the axis of which is perpendicular to the axis of the bevel gears 110, 114.

As already mentioned, the gear drive 32 is driven via the lower conical pulley 18 at a speed which depends on the position of the belt 20 · Since the lower

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Pulley 18 turns in the same direction, turn also the gear mechanism 32 and the bevel gears 108, 112 always in the same direction.

Depending on which of the couplings 106, 107 with the shaft 104 is coupled (the other coupling is separated from the shaft 104 and runs freely), the shaft 104 rotates in one direction or the other. The bobbin bank 98 and the spool 30 moves up and down. As can be seen in the embodiment of FIG. 1, the coil bank 98 moves downwards when clutch 106 is excited (down clutch), while when the clutch 107 is excited (up clutch) the bobbin bank 98 is guided upward.

A brake 116 is used to stop the W lie 104 and thus the coil 98 if both clutches fail, which could happen, for example, in the event of a power failure. During normal operation the brake 116 is held electrically open; in the event of a power failure, the brake is actuated by spring force.

The clutches 106 and 107 are preferably electrically operated and controlled by the circuitry shown in FIG. The up clutch 107 is energized when it is normal open contacts IiR-1 between the G-Ie lohe troi lines 118 and 120 are closed. In a similar way, the

009815 / U98 original inspected " _1fr "

Down clutch 106 energized when the normally closed contacts LR-2 between the same lines 118 and 120 are closed. The current delay properties of the electric changeover clutches ensure a suitable holding force for the coil bank. This avoids "crossing" the bobbin.

All contacts LR-1, LR-2, LR-3 and LR-4 are controlled by the latching relay 74. The coils LR-R and LR-L of the rush relay 74 can be excited alternately, and the rush relay 74 is constructed in such a way that, regardless of whether the relay coil LR-R or the reset coil LR-L is excited, all four contact pairs LR- 1, LR-2, LR-2 and LR-4 are switched and remain in their new positions until the other of the coils IJl-R and LR-L is energized. The contacts LR-1, LR ~ 2 _t LR-3 and LR-4 are directly attracted by the electromagnet of the relay coil LR-R. Therefore, upon energization of the coil LR-R contacts LR-1 _T LB-2, LR-3 and LR-4 in their electromagnetic _postures} moved into which they are mechanically held by the indicated at 121 by mechanical means, regardless of whether the Eelaisspule LR-R remains energized * the electromagnet of Rückstellspnl "- LR-Ii does not affect unmictelbar on äi.t Lon contacts LR-1, ·, IiE-C. LV- * imi. LR-4, but acts "~, f;? * Es; *! \ S ■ ';" ■. ■ u ⁴ ' r iiechanj sd · * "'-.- :. ■ τ- & κ ~: ~: - zl 121 such., s -.;: .. '

that the

ORIGSNAL INSPECTED

dingt · position according to FIG. 3 can return. The holding means 121 'represent a memory that prevents the 'When the machine is restarted after it has been shut down for any reason, the bobbin bank will move into the wrong redemption moved

Since there are five pairs of contacts LRfI * LR-2, LR-3 and LR-4 and CR-1, all of which alternatively assume one of two positions can, there are different contact positions, which are to be identified separately. There are also four different time segments that are used in a lateral shift cycle BU take into account: The time segment t ^, during which the coil UEt-S is energized and the coil LR-L is de-energized; the period of time tg during which both coils LR-E and LR-L are energized 'Los are ι the time segment t, during which the coil LR-L and the coil IB-R is de-energized; and the period of time t ^, during which both coils LR-R and LR-L are de-energized. The time periods t, | and tx are essentially the same length *, the time segments tg and t ^ are essentially the same but considerably longer than the time segments t ₁ and t 1. Sohliefilioh can be observed that the contacts LR-1 in their closed position to carry out a first operation such as the excitation of the upward coupling 107, the contacts LR-2 in their closed position to carry out a "wide operation such as the excitation of the downward Coupling 106 and contacts CH-1 in their closed position

'009815/1498 bad original - 16 -

to carry out a third operation such as the excitation of the switching electromagnet 50 for the belt link 28 to serve.

The operation of the device will now be described. Fig. 3 explains the case where the reset coil LR-L the The last energized coil is so that all contacts LR-1, LR-2, LR-3 and LR-A- are in their normal or mechanical-related positions are. Since contacts LR-2 are closed, the clutch is down 106 switched on, and the coil 30 is moved relative to the wing 16 downwards. At the lower end of this transverse shift contact cams 82 and 84 and close the limit switch 76 shown in FIG. 3. This causes the relay coil LR-R energized, and all contacts LR-1, LR-2, LR-3 and LR-4 are switched. The contacts LR-1 are thereby closed »- sen and engage the up clutch 107; The contacts LR-2 are open so the down clutch is off; the coil bank 98 thus begins to move upwards. The aforesaid deceleration property eliminates "overtravel" of the Spool bank 98 during the reversal of the transverse displacement. Simultaneously Contacts LR-3 are closed, creating a circuit across switch 76, contacts LR-3 and the control relay CR is manufactured. As a result, the tax » relay the contacts CR-1 closed and the electromagnet 50 switched on. By switching on the electromagnet 50 the piston of the piston-cylinder device 42 is in the past

00981 5/1 / -9 8 - 17 -

shifted manner written so that the belt link 28 is moved to the right via the gear mechanism 36 in FIG.

A gear drive 130 is actuated by the movement of the rack 34 and rotates the spindle 90 », whereby the nuts 86 and 88 can be brought closer to one another in order to shorten the subsequent transverse displacement. The length 1 of a given Transverse displacement is of course a puncture of the distance between the contact cams 80 and 82.

When the upward clutch 107 has caused such an upward movement of the coil bank 98 that the contact cams 82 and 84 separate from one another, the limit switch 76 is opened so that the relay coil LR-R is de-energized. Since the relay coil 74 belongs to a rush relay, the contacts LR-1, LR-2, LR-3 and JJR-M- remain in their magnetic-related positions. By opening the limit switch 76, however, the circuit is interrupted via the still closed contact LR-3 and the control relay CR, so that the relay CR is de-energized, the contacts CR-1 open and the switching solenoid 50 through its return spring 54 · in returned to its normal position. (In Fig. 1, the valve 48 is shown in its switching position, not in its normal position). When the valve 48 returns to its normal position, the pawl 38 rotates freely and does not guide the belt link 28 to the left, which rather remains in its new position.

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The contact cams touch each other at the upper end of the transverse shift " 80 and 84, which close the limit switch 78 and the reset coil Switch on LR-L of impulse relay 74. This enables all contacts LR-1, LR-2, LR-3 and LR-4 to be switched over in their normal positions shown in Figure 3; furthermore, the down clutch 106 is switched on, again "Overshooting" of the coil bank 98 can be avoided. Through the Schlieseen of the limit switch 78, the control relay CR is also switched on via the contacts LR-4, the contacts CR-1 are closed and the electromagnet 50 is switched as described. When the bobbin bank has moved so far down that the contact cams 80 and 84 separate, the limit switch 78 opened, whereby the reset coil LR-L is de-energized. Since the relay is a surge relay and all Contacts are in their normal or mechanical-related positions, the contacts LR-1, LR-2, LR-3 and LR-4 remain in their new positions, even if the reset coil LH-L is de-energized. By opening the switch 78 is also the circuit through the contacts LR-4 and the control relay CR interrupted, so that the relay CR is de-energized, the contacts CR-1 open and solenoid 50 in its normal position is returned by the return spring 54. The ratchet 38 rotates again in freewheeling mode, so that the belt link 28 remains in its new position.

A restoring motor ^ 4C is via gear 142 .. a clutch 14-4

, i ,: <: '■; 5/1498 - "> 9 -

Bowl · carries a wave $ 14 and Bitsei 146, which is part of the Form transmission 56, connected to the rack 34 to the Belt link 28 and the nuts 86, 88 returned to their starting positions at the end of a winding structure. The Kupp Drehfest ment 144 is connected to shaft 145 via keyway 148 /, but axially displaceable along the shaft by means of a clutch control device 130. The clutch 144 is during the Wrap build-up disengages and becomes at the end of wrap build-up brought into engagement so that the turning back does not have to be done by hand.

The invention thus provides a new, highly effective device for leaning a fibrous material from a supply device and for winding the material onto one Coil created in winding form. Using the pneumatic piston cylinder assembly is a rough, noisy one Working of the contact shaft and impacts on the skip gear, contact cams, winding assembly nuts and contact shaft are avoided. The changeover clutches eliminate "crossovers" the bobbin bank at its reversal parts, since an inevitable holding of the bobbin bank is always maintained. The front whale speed can be varied independently of the machine speed and can considerably exceed 300 rpm, thereby enabling greater work rates. Furthermore, the machine can be stopped in any position of the moving bobbin bank. Of course, the skilled person can numerous modifications to the illustrated embodiment

make, but thereby the scope of the present invention is nieni; leaving. 0 0 9 8 IH / 1 *. 9 t ^:

6AD

Claims (12)

Claims 1. Winding machine, especially a roving machine, flyer or Like., with coil and feed device, with a drive device to rotate the spool and the feeder at different speeds and to the relative Transverse displacement of the spool and the feed device along their axes of rotation, characterized by a Control device for controlling at least one of the large relative speeds (w) of the spool (30) and feed device (16), speed (v) of the transverse displacement and length (1) of the transverse displacement, which control device has a piston-cylinder arrangement (42) which can be reversed at intervals and through whose piston stroke the drive device is adjusted in such a way that at least one of the variables (w, v, 1) is controlled by the control device. 2. Machine according to claim 1, characterized by contact cams arranged at a distance along the transverse displacement path (80, 82) and a contact cam (84) carried along during the transverse displacement, which when it hits one of the contact cams (80, 82) at the ends of the transverse displacement each have a device (106, 107) for reversing the transverse displacement turns on and when it hits at least one of the contact cams (80, 82) an actuation of the Piston-cylinder arrangement (42) for the purpose of changing the 0 0 9 8 1 5/1 t, 9 8 - 2 - Status of the contact cams (80, 82) and thus the length (1) of the transverse displacement triggers. 3 · Machine according to claims 1 and 2, characterized by a variable mechanical transmission device (14, 18, 20) in the drive device driven by the piston-cylinder assembly (42) is adjusted at intervals while changing the relative speed (w). 4 «machine according to claims 1 to 3» characterized in that that the variable transmission device consists of two conical pulleys (14, 18) and a conical belt (20) consists, which upon actuation of the piston-cylinder assembly (42) is adjusted by this along the pulley axes. 5. Machine according to claims 1 to 4, characterized in that that the piston cylinder assembly (42) has a pawl (38) adjusts the conical belt (28), which pawl rotates freely when the piston (43) returns. 6. Machine according to claims 1 to 5 »characterized in that from the shaft of the output belt pulley (18) the drive branch (100 to 114) for the transverse displacement is derived, so that by the actuation of the piston-cylinder assembly (42) also the speed (v) dte »transverse displacement is changed. 009815 / U98 - 3 - 7 · Machine according to claims 1 to 6, characterized by a return motor (140), which via a clutch (150) can be coupled to the parts of the control device which are adjustable by the piston-cylinder arrangement (42) in order to convert them into returned to their original position. 8. Machine according to claims 1 to 7 »characterized in that the drive device (100 to 114) for the Transverse displacement includes two counter-rotating clutches (106, 107), of which for each transverse displacement * direction one switches through the drive path. 9 · Machine according to claims 1 to 8, characterized in that that the piston-cylinder assembly (42) with flow control valves (61, 61 '), which control the operating speed of the piston-cylinder arrangement. 10. Machine according to claims 1 to 9 »characterized in that that the piston-cylinder arrangement (42) is provided with a pressure monitor (63) which, in the event of a compressed air failure, the Machine stops. 11. Machine according to claims 1 to 10, characterized in that the shaft (104) lying in the An-ritbepfad for dl »transverse displacement with a bit (116) vers« ^v .t ", di® with simultaneous failure of both Couplings (IQ ^ 107) the * · sSiula tr «mat. 009815 / U98 1 b 3 b U ^ b ti 12. Circuit arrangement for controlling a fascine according to An-Proverbs 1 to 11, characterized in that 4 £ e contact is made by one of the limit switches (76 or 78) for the transverse Terso shift alternately the down clutch (106) or dit up «clutch (107) until the respective other limit switch are switched on and that preferably each limit switch briefly during the contact an electromagnetically operated reversing valve (48) for the piston-cylinder arrangement (42) is switched on, wherein during the remaining period of time, a transverse shift the exchange valve and piston cylinder assembly (42) in return to their original position. 13 · Circuit arrangement according to claim 12, characterized by a relay that is latched in both switching positions (74) with switching coil (LR-R) and reset coil (LR-L), which are in parallel current branches (66, 66) lie, one of which in each case by the limit switches (76, 78) at the reversal points the transverse shift is closed; through four contact pairs (LR-1, LR-2, LR-3, LR-4), of which one pair of contacts (LR-1), which is open in the basic position, is in series with one of the couplings (upward 8-coupling 107) and one pair of contacts that is open in the basic position (LR-2) is in Row old of the other clutch (downward s-clutch 106) lie; through a control relay (CH) with a contact pair (CR-I) which is open in the basic position, which (CS-1) in series with the switching solenoid (50) for the 00 9 8 15 / U 9 8 OR, G! NAL I Reversing valve (48) of the piston-cylinder arrangement (42) is located, whereby the coil of the control relay (GH) together with a normally closed contact pair (LR-4) of the relay (74) in shunt to the reset coil (LR-L) and together with a contact pair that is open in the basic position (LR-3) of the relay (74) is shunted to the switching coil (LR-R). 0 0 3 8 1 5/1 /. 3 tr Blank page