CN110615320B

CN110615320B - Cartridge changer for a spinning preparation machine and method for changing a cartridge

Info

Publication number: CN110615320B
Application number: CN201910536218.1A
Authority: CN
Inventors: 奥特马尔·科瓦奇
Original assignee: Maschinenfabrik Rieter AG
Current assignee: Maschinenfabrik Rieter AG
Priority date: 2018-06-20
Filing date: 2019-06-20
Publication date: 2023-01-03
Anticipated expiration: 2039-06-20
Also published as: BR102019012872A2; EP3584207B1; EP3584207A1; DE102018114772A1; CN110615320A

Abstract

The invention relates to a drum changer (1) for a spinning preparation machine, wherein the drum changer (1) comprises at least one first driver (3) and a second driver (5) upstream of the first driver (3) in a predetermined transport direction (T) of a sliver can (8), wherein the first driver (3) and the second driver (5) are supported on a movably guided carrier structure (6) of the drum changer (1), wherein it is proposed according to the invention that at least the first driver (3) can be initially moved from its second position into a third position opposite the transport direction (T), wherein the drum changer (1) comprises a stop (9) which is arranged in such a way that the first driver (3) comes into contact with the stop (9) when it is moved into the third position and in this case moves relative to the carrier structure (6).

Description

Cartridge changer for a spinning preparation machine and method for changing a cartridge

Technical Field

The invention relates to a can changer for a spinning preparation machine, preferably for a drawing frame, carding machine or combing machine, for moving a sliver can, wherein the can changer comprises at least one first and a second driving means downstream of the first driving means in a predetermined transport direction of the sliver can, wherein the first and second driving means are mounted on a movably guided carrier structure of the can changer, wherein the carrier structure together with the first and second driving means can be moved by means of a drive in the mentioned transport direction from a first position into a second position and from there again into the first position, wherein the driving means are designed such that the sliver can be moved in the transport direction during the movement from the first position into the second position, respectively, and wherein at least the first driving means are movably mounted on the carrier structure such that the first driving means can be moved relative to the carrier structure from a basic position.

Furthermore, a spinning preparation machine is proposed, which is preferably in the form of a draw frame, a carding machine or a combing machine, and a method for changing a sliver can at a spinning preparation machine by means of a can changer, wherein the can changer comprises at least one first and a second driver downstream of the first driver in a predetermined transport direction, wherein the first and second drivers are mounted on a movably guided carrier structure of the can changer, wherein the carrier structure together with the first and second drivers can be moved by means of a drive in the mentioned transport direction from a first position into a second position and back therefrom into the first position, wherein the drivers can each move the sliver can in the transport direction during the movement from the first position into the second position, and wherein at least the first driver is movably mounted on the carrier structure such that the first driver can be moved relative to the carrier structure from a basic position.

Background

Such cartridge changers are known from the prior art. The cartridge changer is used to move the sliver cartridge during the changing process. In this case, the sliver can is moved from the waiting position into a filling position of the spinning preparation machine. In general, spinning preparation machines have a sliver placer in the region of the filling station, by means of which sliver can be placed into the sliver can. The fiber strand is, for example, a fiber strand warped by a drawing device of a drawing frame in the case of a drawing frame.

Obviously, the spinning preparation machine also has a plurality of waiting and/or filling positions. This is the case, for example, in so-called double-head drawing frames, in which two drawing frames are arranged next to one another. In this case, each drawing frame is associated with a filling position which has a corresponding sliver placer in the form of a rotary table which in turn is supplied with the fiber sliver by its own drawing frame.

If the can currently in the filling position is now filled with sliver to a defined degree of filling, it is necessary to remove the filled can from the filling position and at the same time move the empty can from the waiting position to the filling position.

Disclosure of Invention

The object of the invention is to provide a drum changer which causes a corresponding displacement of filled and empty sliver cans and in this case requires a relatively small space requirement.

The drum changer according to the invention now comprises a first and a second driver, wherein the two drivers are designed to move the sliver cans in each case when the respective driver is moved together with the carrier structure, wherein the drivers are fastened to the carrier structure.

The support structure comprises, for example, a slide, preferably movable in the horizontal direction, on which the first and second entrainment members are supported. Preferably, the two entrainment members are pivotable about a pivot axis, wherein the pivot axis preferably extends vertically.

If the now empty sliver can is located downstream of the first driver, as viewed in the transport direction of the drivers, and the filled can is located downstream of the second driver, then a movement of the carrying structure from the first position into the second position causes a movement of both drivers and thus of the sliver can in question in the transport direction in question.

The transport direction is also the direction of movement of the empty can from a defined waiting position to a defined filling position.

By moving the driver, the empty sliver can be moved by the first driver from the waiting position into the filling position, wherein the first driver is moved from its first position into its second position. At the same time, the full sliver can is moved by the second driver from the filling position into a removal position, which is preferably located outside the spinning preparation machine. This is achieved by moving the second catch from its first position into its second position.

After the so-called displacement process, the support structure is moved into the first mentioned position, in which the two entrainment members also each occupy their first position. The first driver can in this case be moved back into its first position without the risk of collision with the sliver can, since at this point in time no sliver can is in the mentioned waiting position. In contrast, the second driver must be moved past the previously moved empty sliver can in the region of the filling position without moving the sliver can.

It is therefore advantageous if the second catch member is movable relative to the carrier structure. Preferably, the second catch is mounted on the support structure so as to be pivotable via the pivot axis. If the carrying structure is now moved back counter to the transport direction from its second position into the first position, the second catch is therefore also moved from its second position into the first position. By means of the relative movability between the second driver and the carrier structure, the carrier structure can be deflected during its movement from the sliver can which is currently in the filling position. The second driver can thus be moved through the sliver can mentioned. In this case, the second catch and thus also the carrying structure must be moved into a third position, which is respectively located upstream of the respective first position, as viewed in the transport direction.

In order to be able to carry out the movement of the second catch, the support structure must be moved relatively far counter to the transport direction. This in turn leads to: the first driver will also move together with the carrying structure into a third position in which it is located upstream of its first position, seen in the transport direction. However, in this case, the first driver has an additional space requirement opposite to the transport direction.

In order to overcome this potential disadvantage, it is now proposed according to the invention that the first driver can be moved into the third position from its second position counter to the transport direction before it again assumes its first position. The cartridge changer further comprises a stop arranged such that the first driver, when it is moved into the third position, comes into contact with the stop and in doing so moves relative to the carrying structure.

The stop element is thus a limitation of the movement of the first driver, which causes the first driver to be able to move a small distance counter to the transport direction, as would be the case if the stop element were not present. The distance covered by the first driver during its movement in the transport direction between the respective positions is therefore reduced compared to the case in which no stop is present. The stop comprises one or more members which protrude, for example, upwards from the bottom surface of the cartridge changer. If the first driver is now moved in the direction from its second position toward its third position, the first driver comes into contact with the stop after a certain movement and thus moves relative to the support structure.

In particular, the stop should be arranged such that it comes into contact with the one third of the first driver which is furthest from the carrying structure, in particular furthest from the pivot axis of the first driver.

It is furthermore advantageous if the first driver is supported on the carrier structure via a pivot axis such that it pivots relative to the carrier about the pivot axis when it comes into contact with the stop. In this case, the carrying structure is supported on the guide, along which the carrying structure is moved from its second position into a third position, opposite the transport direction. During this movement, the first driver comes into contact with the stop. From this point in time, the first driver pivots about the pivot axis until the carrying structure reaches its third position.

Subsequently, the carrying structure is moved back into its first position (wherein the movement takes place in the transport direction), wherein if the carrying structure is moved from its second position into the third position, the first driver pivots in this case in a pivoting direction which is opposite to the pivoting direction in which the first driver pivots.

During the movement of the carrying structure from its second position back into the first position via its third position, the first driver is therefore moved, preferably pivoted, first in the first direction and subsequently in the opposite second direction.

It is likewise advantageous if the cartridge changer comprises a basic contour, wherein the first driver is located within the basic contour in each of its positions in a top view of the cartridge changer or protrudes in the horizontal direction by a maximum of 20cm, preferably a maximum of 10cm. The basic contour is a limiting surface which is occupied by the cartridge changer in plan view when the two drivers are in their respective first positions. Now by means of the stop piece it is ensured that: the first driver is always located within the mentioned basic contour or protrudes only by the maximum magnitude mentioned for the basic contour. The space requirement of the cartridge changer is therefore reduced compared to a cartridge changer of identical design, wherein no corresponding stop is present.

It is also advantageous if the stop is part of the bottom surface of the cartridge changer or is fixed to the bottom surface. The cartridge changer preferably comprises a bottom surface in the form of one or more plate-shaped surface sections, via which the cartridge changer can be placed on a substrate, for example on the floor of a hall of a spinning mill. The stop is, for example, an elevation of the base surface, the magnitude of which is measured such that the first driver can come into contact with the stop as described above. Preferably, the stop is arranged upstream of the filling position, viewed in the transport direction. Furthermore, the stop is to be designed as a stationary and rigid unit.

The advantage is also obtained that the first driver is pivoted further in its third position relative to its basic position than in its first and/or second position. Preferably, the first driver occupies the same position with respect to the carrying structure at all times as it moves from the first position into the second position. If the first driver is moved only from the second position into its first position and from there into its third position, it pivots about the pivot axis. Preferably, the angle of pivoting through which the first driver pivots is greatest when the first driver is in its third position. The basic position of the first driver is furthermore a relative position with respect to the carrying structure, which relative position is occupied by the first driver when the first driver is in its first position.

It is also advantageous if the first and second driver each have a contact section for contacting the sliver can. The contact section can be, for example, a rotatable drum which is located at one end of the respective driver.

In particular, the driver can be designed as a driver arm, the respective first end of which comprises the contact section and the respective second end of which is supported on the support structure. Preferably, the contact section is arranged on a respective end of the respective driver facing away from the carrier structure.

The contact sections of the two drivers are always at a distance from one another. Preferably, the minimum distance between the two contact sections is minimal when the first and second drivers are in their respective third positions. It is also advantageous if the mentioned distance remains constant during the movement of the two entrainers from their respective first positions into their respective second positions. The change in the distance is preferably caused by the first driver being moved, in particular pivoted, in the direction of the second driver when the carrying structure is moved into its third position.

Advantageously, the carrying structure can be moved back and forth between the various positions along a preferably linearly configured guide by means of the mentioned drive, which is preferably part of the cartridge changer. The guide can, for example, comprise a guide rail in which the support structure is mounted so as to be movable in the horizontal direction. The movement can in turn be carried out by means of a belt or a chain drive, wherein the chain or belt is connected to a drive (for example an electric motor). It is also conceivable that the carrying structure is moved back and forth between the various positions by means of one or more pneumatic cylinders.

It is also advantageous if the second catch element is also mounted movably on the support structure, so that it can be moved relative to the support structure from the basic position. The support can take place via a pivot axis or via a guide, respectively, via which the respective catch can be moved relative to the carrying structure.

Furthermore, the first and second driver are to be connected to at least one energy store, wherein the energy store applies a force to the respective driver, which ensures that: when no additional force is applied to the catch, the respective catch is in its basic position. The energy store is preferably a spring element, for example in the form of a tension or compression spring or a compression cylinder. The accumulator accordingly ensures: the respective catch is in its first position. Furthermore, the first driver can be moved against the force of the accumulator if it comes into contact with the stop and the carrying structure continues to move counter to the transport direction. Likewise, if the second catch comes into contact with the sliver can in the region of the filling position, while the carrying structure is moved from the second position counter to the transport direction, the second catch can be moved against the force of the accumulator.

Reference is made to the following description regarding other possible features of the cartridge changer.

The subject matter of the invention is also a spinning preparation machine, preferably in the form of a draw frame, carding machine or combing machine, wherein the spinning preparation machine is characterized in that it comprises one or more reel changers arranged next to one another according to the above or following description. Preferably, the spinning preparation mechanism is a double-head draw frame comprising two adjacent drafting devices and two sliver placers (for example in the form of placing trays known from the prior art), wherein one sliver placer is associated with a drafting device each. There is a filling position below the sliver placer, to which an empty sliver can be moved. In this case, each filling position is associated with its own carrying structure comprising at least one first and one second follower, respectively.

Finally, the subject matter of the invention is a method for changing a sliver can in the area of a spinning preparation machine. The cartridge changer comprises at least one first and one second catch, wherein the two catches are each moved from a first position into a second position during the cartridge changing process. In this case, the empty sliver can is moved by the first drive from the waiting position and in the mentioned transport direction into the filling position. At the same time, the filled sliver can is moved in the transport direction from the filling position to the removal position by means of a second catch. In particular, the movement of the sliver can and/or the movement of the first and second drivers and the carrier structure takes place in a linear direction.

Preferably, the two drivers also move simultaneously, wherein the drivers can be fastened in particular to separate support structures, which are moved correspondingly by means of the drive. Reference is made to the above and following description for possible features of the catch and the carrying structure.

In each case, it is provided that at least the first driver is moved from its second position into a third position counter to the transport direction first and in this case comes into contact with the stop. This results in: the first driver moves relative to the load bearing structure. The stop element causes the first driver to move, in particular pivot, relative to the carrying structure since it is in contact with the stop element.

During the preferably continuous movement of the carrying structure counter to the transport direction when moving from its second position into its third position, it is particularly advantageous if the relative orientation of the first driver with respect to the carrying structure changes as long as the first driver comes into contact with the stop. From this point on, the linear movement of the first driver is preferably converted into a pivoting movement, so that the first driver pivots relative to the carrying structure. The section of the first driver which comes into contact with the stop is in this case no longer moved opposite to the transport direction from the contact with the stop, so that the space requirement in this direction is smaller than in a similar spinning preparation machine without a stop.

It is also advantageous if the first driver pivots relative to the carrier about the pivot axis when the first driver comes into contact with the stop. Preferably, the pivoting process takes place about a vertically extending pivot axis. The stop element, when in contact with the first driver, therefore causes a further movement of the section of the first driver which is in contact with the stop element, counter to the transport direction.

The advantage is also achieved that the first driver, after reaching its third position, moves into the first position again and in this case again assumes its basic position. The occupation of the basic position is preferably brought about by an accumulator which is connected to the supporting structure. After the primary position has been occupied, the empty sliver can be moved back into the area of the waiting position and subsequently moved into the area of the filling position by means of the first drive.

It is particularly advantageous if the first driver is moved, preferably pivoted, in the first movement direction from its second position into its third position during its movement. The movement is preferably performed in the transport direction relative to the carrying structure. If the first driver is moved, preferably pivoted, in the second movement direction during its movement from its third position into its first position relative to the carrying structure, this movement takes place in the opposite direction to the first movement direction.

This brings about the particular advantage that the first driver part is moved, preferably pivoted, in the first movement direction against the force of the force accumulator and in the second movement direction by means of the force accumulator. The accumulator thus ensures: when the first driver is not in contact with the stop, the first driver always occupies its basic position.

It is furthermore advantageous if, when the first driver is moved from its second position, preferably via its first position, into its third position, the pivot axis is moved counter to the transport direction and in particular in the horizontal direction. The pivot axis is preferably part of the load bearing structure and moves with said load bearing structure.

Drawings

Other advantages of the present invention are described in the following embodiments. The figures each schematically show:

FIG. 1 shows a part of a spinning preparation machine according to the invention;

fig. 2 to 6 show a top view of a first embodiment of a cartridge changer according to the invention during different points in time for changing a cartridge; and

fig. 7 and 8 show top views of a second embodiment of a cartridge changer according to the invention during different points in time for changing a cartridge.

Detailed Description

Fig. 1 shows a detail of a spinning preparation machine according to the invention in the form of a draw frame. In addition to further components not shown in fig. 1, the drawing frame comprises at least one drawing frame 2 with a plurality of drawing frame rollers 17, by means of which the fiber sliver 15 fed to the drawing frame 2 can be homogenized with respect to its thickness.

The fiber sliver 15 is placed in the sliver can 8 arranged below the drawing frame 2 during operation of the drawing frame 2 via a depositing device preferably in the form of a depositing disk 18. The sliver can 8 is in the filling position of the can changer 1 during the depositing process.

Fig. 2 to 6 show, for example, a top view of a corresponding cartridge changer 1 (drawing frame 2 and setting plate 18 are not shown in this figure for the sake of clarity).

As can be seen from the figures mentioned, the cartridge changer 1 comprises a first driver 3 and a second driver 5, both of which are supported on a common carrier structure 6. The carrier structure 6 is in turn supported in the guide 12 and can be moved back and forth along the guide 12 by means of a drive.

Fig. 2 now shows a state in which the can 8 is shown in fig. 1 in its filling position as far as a predetermined filling level with the sliver 15 from the drawing frame 2. In addition, an empty can 8 is arranged in the can changer 1, which is in a waiting position upstream of the mentioned filling position in the predetermined transport direction T.

If the carrier structure 6 is now moved in the transport direction T from fig. 2 (in fig. 2 the carrier structure has its first position) into the second position shown in fig. 3, the empty sliver can 8 is moved from its waiting position into the filling position. At the same time, the filled sliver can 8 shown in fig. 2 is moved in the transport direction into a removal position, not shown, from which it can be moved, for example, to a spinning machine.

Starting from the second position shown in fig. 3, the support structure 6 must now be moved back into its first position. For this purpose, the support structure 6, as shown in fig. 4, is moved counter to the transport direction T. Since the second driver 5 is supported on the support structure 6 via the pivot axis 10, it can be deflected when passing through the sliver can 8 in the filling position, so that the sliver can 8 does not have to be moved. In order to facilitate the passage, the second driver 5 preferably has a contact section 11 in the form of a roller (obviously, the first driver 3 can also have a corresponding contact section 11). After the second driver 5 has passed the sliver can 8, it again assumes its basic position relative to the support structure 6, wherein a corresponding movement is caused by the energy store 4 (e.g. a tension spring).

A comparison of fig. 4 and 5 now shows the core of the present invention. In order to be able to pass the sliver can 8 in the filling position by means of the second driver 5, the support structure 6 is moved counter to the transport direction. However, the movement of the carrier structure 6 from its second position into the first position shown in fig. 2 is not sufficient for this purpose, since the second driver 5 cannot pivot past the sliver can 8 in the filling position in this position. Instead, the carrying structure 6 must continue to move a distance counter to the transport direction T, so that it finally assumes the third position shown in fig. 5. In this position, however, the first driver 3 usually protrudes beyond the basic contour of the cartridge changer 3, so that an additional free surface is required.

In order to prevent this, the invention now proposes a stop 9, with which the first driver 3 comes into contact when the carrying structure 6 moves from its second position into its third position. In fig. 5 a third position of the carrying structure 6 is shown. As can be seen from said figures, the first driver 3 is pivoted in this position in the transport direction T relative to the carrying structure 6. This results in that the minimum distance a (see fig. 5) between the two contact sections 11 of the first and

second drivers

3, 5 has the smallest magnitude in the third position of the carrying structure 6.

If the carrier structure 6 is now moved back from the third position into the first position (fig. 6), a new, empty sliver can 8 can be moved into the waiting position, and the sliver can 8 can be filled with the sliver 15 in the filling position. In order to bring about the movement of the first driver 3 relative to the support structure 5, which takes place in this case, the first driver 3 is preferably also associated with a corresponding not shown energy accumulator 4.

Fig. 7 and 8 show an alternative embodiment of the cartridge changer 1 according to the invention. As a comparison of the figures shows, the first driver 3 is not mounted so as to be pivotable about the pivot axis 10. Instead, the carrier structure 6 comprises a driver guide 12, in which the first driver 3 is movable relative to the carrier structure 6 in the transport direction T and also opposite to the transport direction T. In this way too, contact between the first driver 3 and the stop 9 can be avoided: the first driver 3 must be moved counter to the transport direction T onto the basic contour of the cartridge changer 1. The space requirement of the cartridge changer 1 is therefore also smaller in this case than if the stop 9 were not present.

The invention is not limited to the embodiments shown and described. Variants within the scope of the claims can likewise be any combination of the described features, even if they are shown and described in different parts of the description or claims or in different embodiments, provided that: no contradiction is made with respect to the teachings of the independent claims.

List of reference numbers:

1. cartridge changer

2. A drafting device,

3. A first driving member

4. Power accumulator

5. The second driving part

6. Bearing structure

7. Driver

8. Sliver can

9. Stop piece

10. Pivot axis

11. Contact section

12. Guide part

13. Basic outline

14. Bottom surface

15. Fiber strip

16. Driver guide part

17. Drafting device roller

18. Placing plate

T direction of transport

A minimum distance between two contact sections of the first and second driver

Claims

1. A can changer (1) for a spinning preparation machine for moving a sliver can (8),

-wherein the barrel changer (1) comprises at least one first driver (3) and a second driver (5) located downstream of the first driver (3) in a preset transport direction (T) of the sliver can (8),

-wherein the first and second drivers (3, 5) are supported on a movably guided carrying structure (6) of the cartridge changer (1),

-wherein the carrying structure (6) together with the first and second drivers (3, 5) is movable in the transport direction (T) from a first position into a second position and from the second position into the first position again by means of a drive (7),

-wherein the drivers (3, 5) are configured to be able to move the sliver can (8) in the transport direction (T) during the movement from the first position to the second position, respectively, and

-wherein at least the first driver (3) is movably supported on the carrying structure (6) such that it can be moved relative to the carrying structure (6) from a basic position,

characterized in that at least the first driver (3) can be moved from its second position into a third position opposite the transport direction (T) first, wherein the cartridge changer (1) comprises a stop (9) which is arranged such that the first driver (3) comes into contact with the stop (9) when it is moved into the third position and in this case moves relative to the carrying structure (6), the first driver (3) being pivotably supported on the carrying structure (6) via a pivot axis (10) such that, when it comes into contact with the stop (9), the first driver (3) pivots relative to the carrying structure (6) about the pivot axis (10), wherein the first driver (3) and the second driver (5) each have a contact section for contacting a sliver can (8), wherein, when the first driver (3) and the second driver (5) are each in their third position, the minimum distance (A) between the two contact sections is minimal.

2. Cartridge changer (1) according to claim 1, characterized in that the cartridge changer (1) comprises a basic contour (13), wherein the first driver (3) is located within the basic contour (13) in each of its positions in a top view of the cartridge changer (1) or protrudes a maximum of 20cm in a horizontal direction.

3. Cartridge changer (1) according to claim 1, characterized in that the stop (9) is part of or fixed to the bottom surface of the cartridge changer (1).

4. Cartridge changer (1) according to claim 1, characterized in that the first driver (3) is pivoted further in its third position with respect to its basic position than in its first and/or second position.

5. Cartridge changer (1) according to claim 1, characterized in that the carrying structure (6) is movable back and forth between various positions along a guide (12) by means of a drive (7).

6. Cartridge changer (1) according to claim 1, characterized in that the second driver (5) is also movably supported on the carrying structure (6) such that it is movable relative to the carrying structure (6) from a basic position, and the first driver (3) and the second driver (5) are connected with at least one force accumulator (4), wherein the force accumulator (4) exerts a force on the respective driver (3, 5), which ensures: when no additional force is applied to the catch, the respective catch (3, 5) is in its basic position.

7. A spinning preparation machine, characterized in that it comprises a cartridge changer (1) according to any one of claims 1 to 6.

8. A method for changing a sliver can (8) at a spinning preparation machine by means of a can changer (1) comprising at least one first driver (3) and a second driver (5) downstream of the first driver (3) in a preset transport direction (T),

-wherein the carrying structure (6) together with the first and second drivers (3, 5) is movable by means of a drive (7) in the transport direction (T) from a first position into a second position and from the second position into the first position again,

-wherein the entrainers (3, 5) are respectively able to move the sliver cans (8) in the transport direction (T) during the movement from the first position to the second position, and

characterized in that at least the first driver (3) is moved after the movement of the sliver can (8) from its second position into a third position opposite to the transport direction (T) and in this case into contact with a stop (9) and in this case is moved relative to the carrying structure (6), the first driver (3) being pivoted about a pivot axis (10) relative to the carrying structure (6) when the first driver (3) is brought into contact with the stop (9), wherein the first driver (3) and the second driver (5) each have a contact section for contacting the sliver can (8), wherein the minimum distance (A) between the two contact sections is minimal when the first driver (3) and the second driver (5) are each in their third position.

9. Method according to claim 8, characterized in that the first driver (3) moves into the first position again after reaching its third position and in this case again occupies its basic position.

10. Method according to claim 8, characterized in that the first driver (3) moves from its second position into its third position during its movement in a first direction of movement and in that the first driver (3) moves from its third position into its first position during its movement in a second direction of movement, wherein the first direction of movement is opposite to the second direction of movement.

11. Method according to claim 10, characterized in that the first driver (3) is moved in the first movement direction against the force of an accumulator (4) and in the second movement direction by means of the force of the accumulator (4).

12. Method according to claim 8, characterized in that the pivot axis (10) moves opposite to the transport direction (T) and in a horizontal direction when the first driver (3) moves from its second position into its third position.