DE2065369A1 - DEVICE FOR SWITCHING MULTI-STAGE GEAR CHANGE GEARS - Google Patents

Description

Device for switching multi-stage gear change transmissions The main patent ... (patent application P 19 30 046.0-21) relates to measures for switching of multi-stage gear change transmissions, especially for iast vehicles, whereby which are axially displaceable to convey different gear ratios Gears or toothed switching elements are moved electro-hydraulically, and after the triggering of a level change, the disengagement of those that have been effective Stage, the subsequent establishment of synchronous operation for the selected Stage to be brought into engagement gears or switching elements and the engagement of the same takes place automatically in each other, preferably including the uncoupling of the drive motor before said disengagement and a new coupling the mentioned indentation. The device according to the main patent (Patent application P 19 30 046.0-21) to carry out the switching has an electrical or electronic Control part on that by hand and / or automatically depending on the engine load and speed and the effective gear stage is triggered or starts, and controls the automatic sequence of each level change, and continues to be with a Hydraulic fluid source and equipped with actuating cylinders, their pistons each are connected to one of the gear parts to be moved when changing levels.

To ensure fast switching of multi-stage gear change transmissions is proposed according to the main patent (patent application P 19 30 046.0-21), the engagement the gears or switching elements suddenly through when their synchronous operation occurs make the piston of a hydraulic actuating cylinder by moving this piston over an instantaneous, two-pin electro-hydraulic control suddenly acted upon by a sufficiently large hydraulic fluid volume for its displacement or is relieved of it. In further perfection there will be a separate rapid Circulation deceleration or acceleration of one of the two with each step change engaged with each other. gear parts to be brought to achieve their synchronous operation made while the connections of this transmission part to the transmission upstream drive motor and to be driven downstream of the gearbox Shaft to decelerate or accelerate only slightly wet be interrupted.

The one to achieve. synchronous operation of the two with each level change Gearbox parts to be brought into engagement with one another, revolution delay to be carried out or -bes chl eu inclination of one of the two transmission parts is particularly when it is reached the disconnected position of the previously engaged gear parts.

The aforementioned apparatus for performing this switching is according to the main patent ... (patent application P 19 30 046.0-21) characterized in that that the actuating cylinder each with at least one hydraulically operated 2-position 3-way main valve are connected via a line with a large inner diameter, which is also connected to a serving as a pressure fluid source pressure fluid reservoir and to a fluid collecting container is connected via cables with a large inner diameter and in each switching direction releases a large cross-section and an electromagnetic 2-position 3-way pilot valve is controlled with a small excitation coil connected to the control part, which in each switching direction releases only a small cross-section and on the one hand with the actuating cylinder of the associated main valve, on the other hand with the hydraulic fluid reservoir and the liquid collecting container via lines with a smaller inner diameter in Connection.

Each axially movable gear or

Shift element in two different gear stages in each other Toothing engageable LLccl. ~ wnd. be connected to a piston, which in a Cylinder is movable in two end positions and a central position, in which cylinder.

three lines with a large inner diameter open, one of them with the hydraulic fluid reservoir and the other two with one hydraulically operated each, 2-position 3-way main valve controlled by an electromagnetic 2-position 3-way pilot valve are connected.

Each cylinder can have an annular stop which the cylinder in a front section, in which the gear or switching element to be moved connected first piston runs, and divided into a rear section in which a second piston is running, which when planting on the ring stop with his piston rod protrudes so far into the front cylinder section that the the first piston resting on the free end of this piston rod is in the central position is located.

In the lines between the hydraulic fluid reservoir and the pre as well as main valves can be an electro-magnetically operated 2-position 3-way valve be switched on, which is also connected to the liquid collecting tank via a further line is connected, so that deytetztgennnnten in one switching direction Valve of the hydraulic fluid reservoir and in the other switching direction of the fluid collecting container is connected to the lines to the pilot and main valves and the cylinders.

The electro-magnetically operated pilot valves and the hydraulically operated main valves, but at least the pilot valves can be used as seat centiles be designed, for example, as ball seat valves.

Particularly preferred is the embodiment according to which one of the each Gear parts to be brought into synchronous operation, which when disengaged Drive motor and disengaged gear stages run freely, with a separate, optionally ~ accelerating or decelerating, influenced by the electrical control unit Device is connected. The device is preferably a hydraulic one Unit that acts as a motor or pump.

Instead, the device mentioned can also consist of a separate braking device and a separate motor. Preferably the device is with connected to the secondary shaft of a main and secondary shaft having transmission.

The friction clutch upstream of the transmission can be operated by a hydraulic Actuating cylinder can be actuated from the piston with the moving part of the clutch is in connection, the cylinder with a controlled by the electrical control part, Electro-magnetically operated valve assembly is connected, which is also connected to the Hydraulic fluid reservoir and the fluid collecting container is connected.

The object of the invention is a further improvement of the object Main patent ... (patent application P 19 30 046.0-21) with regard to a reduction the components and the space required by the switching device.

This is achieved by the measures specified in the main claim. The invention is further perfected when those specified in claims 2-13 Features are realized.

In the device according to the invention there are always only two adjusting cylinders required, regardless of how many gear ratios the gearbox to be shifted having. Not only are extremely few components required, but space requirements is also considerably reduced. The switching times are not extended, because the axial adjustment of the selector shaft is carried out while the one another gear parts to be brought into engagement are brought into synchronism.

Below is an embodiment of the invention with reference to the accompanying drawings Drawings described for example. Show in it: Fig. 1 a partially cut-away side view of a device with a device according to the invention provided gear in a schematic representation; Fig. 2 is a view of the section along the line II-II in Fig. 1, also in a schematic representation; Fig. 3 the partially cut-away plan view of the embodiment according to FIGS. 1 and 2, also in a schematic representation; 4 shows the hydraulic circuit diagram the switching device according to FIGS. 1 to 3.

In the device according to the invention shown in the drawings it is one with which a truck can be equipped can. Its motor, not shown, is via a shaft 2 with a friction clutch 3 connected, the movable part 4 on the drive shaft 5 of the gear change transmission 6 Securely seated, but axially displaceable. Instead of a lid, the Gearbox 6 flanged the switching device 7 to be explained.

The transmission 6 is of conventional design and has a main shaft 8 and a secondary shaft 9. The main shaft 8 provides the one to be driven The transmission output shaft connected to the vehicle wheels. It is via the auxiliary shaft 9 connected to the transmission drive shaft 5.

For this purpose, the gears 10 to 17 and the shift sleeves 18, 19 are provided. The gearwheel 10 is on the shaft 5, the gearwheels 11, 12, 13 are on the shaft 9 and 14 are each wedged non-rotatably and axially immovable. While that Gear 11 of the shaft 9 with the gear 10 of the shaft 5 combs, stand the gears 12, 13 and 14 of the auxiliary shaft 9 in 6-hour engagement with the gears 15 or

16 or 17 of the transmission 6, which is axially immovable on the main shaft 8, but are freely rotatable.

In contrast, the shift sleeves 18, 19 on the main shaft 8 are torsion-proof, but axially displaceable so that they jLitt their mutual teeth 20 optionally in corresponding toothing on gear 10 and 15 or 16 and 1? indented can be. In the case of the sleeves 18, 19 shown in FIG middle StelluRgX then all the gears run when the shaft 5 rotates 10 to 17 and the auxiliary shaft 9 of the transmission 6 sit, but not the main shaft 8th.

This is only taken when the switch sleeve 18 or the Shift sleeve 19 pushed into toothing 20 of gear 10 or 15 or 16 or 17 will. At the same speed of the shaft 5, the shaft 8 rotates at different speeds Speed counts, depending on the gear 10, 15, 16 or 17, with which sle by means of the shift sleeve 18 or 19 is connected. At the same speed of rotation of the shaft 5, the engagement mediates the sleeve 19 in the toothing 20 of the gear 17 the lowest speed of the shaft 8, the engagement of the sleeve 19 in the toothing 20 of the gear 16 is greater Speed of the shaft 8, the engagement of the sleeve 18 in the toothing 20 of the gear 15 again a higher speed of the shaft 8, and the engagement of the sleeve 18 in the toothing 20 of the gear 10 the highest possible speed of the shaft 8, which is equal to the speed of the shaft 5. Of course, only one of the both sleeves 18, 19 are indented, and the other must then be in the ii Fig. 1 reproduced middle position.

Another gear 14 'is keyed on the secondary shaft 9, on the other hand an additional gear-17 'on the main shaft 8 axially immovable, however is freely rotatable. When engaging one on an auxiliary auxiliary shaft 9 'axially displaceable gear 20 'in the gears 14' and 17 ', the two Sockets 18 and 19 are in the middle position shown in FIG. 1 the direction of rotation of the main shaft 8 is reversed, so the reverse gear is switched on.

The axial displacement of the shift sleeves 18 and 19 and the gear 20 'takes place in each case by means of an arm 21 which is inserted into an annular groove in the sleeve 18 resp. 19 or the gear 20 'engages and on one of the shafts 5, 8, 9 and 9 'vertical and rotatably mounted shaft 22 is attached. On the arm 21 facing away from the side, each shaft 22 has a further non-rotatably connected thereto Arm 23 up.

In the cover-like component 7, two are to each other and to the shafts 5, 8, 9 and 9 'parallel rods 23t mounted axially displaceably, which are articulated at the end of the arm 23, the-the shift sleeve 19 or the gear 20 ' assigned. The other end of the arms 23 'are coaxial with the end of the Arm 23, which is assigned to the shift sleeve 18. At the coaxial arm ends is in each case a lever 23 "is articulated, which is attached to a switching ring 23" '. The three mutually coaxial switching rings 23 '' 'sit freely rotatable on a switching shaft 24, which is axially displaceable in the rings 23 "'. The switching shaft 24 is with equipped with a wedge 24 ', which ae after the axial position of the shift shaft 24 engages in an inner longitudinal groove of a switching ring 23 '' 'and takes it with it, when the shift shaft 24 is rotated.

The shift shaft 24 is rotatable in three angular positions, so that each shift sleeve 18 or 19 is adjusted in three positions, namely the one shown in Fig. 1 reproduced middle position and a left and right end position in which the left and right mutually adjacent toothings 20 with each other are engaged.

The arm 21 of the gear 20 'only needs to be moved in two positions to be, in which the gear 20 'is engaged in the gears 14' and 17 'or has moved out of it.

According to FIG. 4, the selector shaft 24 is rotated thereon Pinion 24 "is provided, which is secured against rotation with the selector shaft 24, but axially is slidably connected. The gear rack, which is designed as a rack, meshes with the pinion 24 ″ Rod 25 of a piston 26, which together with a second piston 27 with piston rod 28 is guided axially displaceably in a cylinder 29. The piston 26 is still on To be described movable in three different positions, namely on the in Fig. 4 reproduced central position, in a left end position, in which he is on a Ring stop 70 of the cylinder 29 rests, and in a right end position in which it is brought into contact with the right inner end face of the cylinder 29. Everyone these three positions of the piston 26 are three angular positions of the associated Shift shaft 24 and thus also three positions via the coupling linkage described assigned to the shift sleeve 18 and 19, respectively. In the central position of the piston 26 is located the shift sleeve 18 or 19 assigned to it is also in the middle, disengaged Position, as can be seen from FIG. In the left end position of the piston 26 is the Shift sleeve 18 or 19 with their teeth 20 in the teeth 20 of the gear 15 or 17 engaged, in the right end position of the piston 26, however, the shift sleeves are 18, 19 with their teeth 20 engaged in the teeth 20 of the gear 10 and 16, respectively.

The actuating cylinder 29 is operated hydraulically and therefore has several Connection lines, which with a Druckfluigkeftsquelle or with a pressureless collecting container can be connected. A hydraulic fluid line ignites 31 in the vicinity of that inner end face in the cylinder 29, which is from the piston rod 25 is penetrated. This line 31 is on one side of an electro-magnetic 2-position 3-way vent ii s 32 connected, the other side via a liquid line 33 is connected to a hydraulic fluid reservoir 34. This is from a Puepe 35 fed with hydraulic fluid, with excess hydraulic oil over the Line 36 and the overflow valve 37 after the reservoir 34 has been filled into the liquid reservoir 38 flows back Furthermore, the valve 32 protrudes with the mentioned other side a return line 39 with the liquid collection container 38 in connection. It thus, three liquid conduits emanate from the valve 32 in addition to the conduit 31 open into the cylinder 29, the two further lines 40 and 41. During the line 40 in the cylinder end face penetrated by the piston rod 25 opposite rear end face of the cylinder 29 opens, the line runs 41 in the vicinity of the ring stop 30 in the cylinder 29. The lines 40, 41 are each connected to a hydraulically operated 2-position 3-way main valve 42 or 43 connected, on the other hand via a liquid line 44 or

45 connected together with the line 31 to the valve 32 already mentioned and via a line 46 or 47 to the liquid collecting container 38 leading return line 39 is in communication. The two main valves 42, 43 are each via a line 48 or 49, which to the actuation cylinder 50 or 51 of the main valve 42 or 43 is connected, one each electromagnetically actuated 2-position 3-way pilot valve 52 resp.

53 upstream.

In addition to the line 48 and 49 go from the pilot valves 52 and 53, respectively on the other hand, in each case a liquid line 54 or 55 leading to the valve 32 and a line 56 or 57 connected to the return line 39.

To adjust the pistons 26 and 27 in the cylinder 29 suddenly and accordingly, the required quantities of fluid in the corresponding sections of the cylinder 29 The fluid lines are extremely fast flowing in or allowing them to flow out of it 31, 40, 41, 44, 45, 46, 47 as well as 33 and 39 with a correspondingly large inner diameter provided, furthermore the valves 32, 42 and 43 designed so that they are in each switching direction also release a correspondingly large cross-section.

It also contributes to the sudden adjustment of the piston 26 in the cylinder 29 with a corresponding command of the control part, not shown, the fact in that the lines 40 and 41 each have a large-volume main valve 42 and 43, respectively is assigned, which is provided by a small-volume electromagnetic pilot valve 52 or 53 is controlled hydraulically.

The valves 52, 53 require only small switching forces for their actuation, so that the electrical coils are small and the magnetic fields to be built are small Are strengths that are built up quickly. When the valves 52 are actuated, 53 the downstream valves are actuated practically at the same time 42 or 43, since the hydraulic connection between the valves 42 and 52 or 43 and 53 practically no delay occurs.

In addition, this also allows for a quick switchover of the Lines 40, 41 on the valve 32 or the return line 39 ensure that the valves 42, 43, 52 and 53 are designed as ball seat valves, which do not have any positive coverage path of the locking members and thus very short working strokes own. For common valves with centric, rotationally symmetrical control spools and around these annular pressure spaces arranged there is a positive overlap of the pressure chambers by the control slide is required to minimize leakage oil losses to keep it low. With each actuation, the path of this overlap must first be determined must be covered before the control slide releases a switching direction.

This requires additional time and the magnet of the Due to the longer stroke, the valve is correspondingly powerful, i.e. with a high winding inductance be formed. All these disadvantages are the ball seat valves 42, 43, 52 and 53 not given.

The hydraulically operated one is used to axially adjust the selector shaft 24 Adjusting cylinder 29 ', which, corresponding to the adjusting cylinder 29, is also available as a three-position cylinder is formed and has the same structure. The same components are included the hydraulic lines are provided with the same reference numbers that have been deleted. In each of the lines 40 'and 41' there is only a single one, not shown Control part made of controlled electro-magnetic, designed as a ball seat valve Valve 42 'or 43' switched on, which via a line 44 'or 45' with the Ventii 32 and via a line 46 'or 47' with the return line 39 in connection stands.

The axial position of the switching shaft 24 is controlled by switches 82 ', 83' and 84 ', which are from the piston rod 25' or instead from the switching shaft 24 self operated are reported to the control part, not shown, to indicate with which switching ring 23 '' 'the switching shaft 24 over the wedge-like Finger 24 'is engaged. The piston rod 25 acts in the same way with switches 82, 83 and 84 together to indicate to the control part in which shaft position the shift shaft 24 is located.

The electromagnetic valves 32, 42t, zu, 43 ', 52 and 53 are via electrical lines not shown with the one also not shown Control part connected, likewise mentioned the switches 82 to 84 and 82 ' to 84 '. Furthermore lead to the control part according to the main patent ... (patent application P 19 30 046.0-21) two electrical lines, each connected to a not shown Tachometer are connected, which is connected to the main gear shaft 8 or the gear shaft 9 circulation, Finally, there is also an electrical line from the control unit for controlling the hydraulic actuation of clutch 3 and the one to be described Device 58.

The operation of the entire switching device 7 is identical to that of the switching device according to the main patent ... (patent application P 19 30 046.0-21), apart from the fact that with each gear stage change only the same Valves 42, 47, 52, 53 and the same actuating cylinder 29 are actuated, which via the pinion 24 ″ and the shift shaft 24, however, to another shift sleeve 18 or 19 or the gear 20 'acts, the axial adjustment of the switching shaft 24 is always carried out by means of the actuating cylinder 29 'when the shift sleeves 18 and 19 and the gear 20 'are disengaged and the two with each other To be brought into engagement gears 20 are brought into synchronism, so that any extension of the switching time is excluded.

The secondary shaft 9 of the transmission 6 has a hydraulic unit 58 connected, which can act either as a motor or a pump. The unit 58 has a coaxial gear 58 'which meshes with the gear 17 on the main shaft 8, which in turn meshes with the gear 14 on the auxiliary shaft 9. The gear 17 is freely rotatably mounted on the main shaft 8, while the gear 14 on the Secondary shaft 9 is keyed against rotation.

The unit 58 can, for example, via a not shown: Liquid supply line and a liquid discharge line, also not shown with an electromagnetically operated 3-position 4-way valve (not shown) be connected, the other with the hydraulic fluid reservoir via two lines 34 or the pressureless liquid collecting container 38 is in communication a switching position of the valve mentioned, all lines are shut off so that the hydraulic unit 58 acts as a pump which is fed into the liquid discharge line and from there into another line against a pressure relief valve connected to it promotes, which opens to the liquid supply line from which the unit 58 Hydraulic fluid sucks. The unit 58 must be the one set on the pressure relief valve Maintaining the opening pressure at all times, thus has a braking effect on the auxiliary shaft 9 of the gearbox 6.

In the second position of the valve mentioned are those with the hydraulic fluid reservoir or lines connected to the unpressurized liquid collecting tank still shut off, the liquid supply line and the liquid discharge line but connected to each other, so that the line bridges with the pressure relief valve is. The driven by the auxiliary shaft 9 So unit 58 works still as a pump, but without any pressure in the liquid supply line and the liquid discharge line, without having to be practical exert a braking effect on the auxiliary shaft 9. In a third switch position the valve connects the fluid supply line with that to the pressure fluid reservoir 34 leading line, also the liquid discharge line with the unpressurized Fluid collecting tank 38 connected line, so that the hydraulic unit. 58 is acted upon with hydraulic fluid from the memory 34 and act as a motor can that drives the auxiliary shaft 9.

As can be seen from Fig. 1 of the accompanying drawings, the Device 58, however, also consists of a separate friction clutch and a separate one Be composed of drive motor, which also from the control part mentioned can be controlled from.

To actuate the friction clutch 3 with the inventive Device provided truck can a not shown adjusting cylinder be provided, the piston of which is connected to the movable part 4 of the clutch 3 is. The cylinder is connected to a line with a hydraulically operated 2-position, 3-way valve in connection, on the other hand via a further line to the hydraulic fluid storage tank is connected to the liquid collection container via an additional line. The actuating cylinder of the valve is connected to an electro-magnetic via a line operated 2-position 3-way pilot valve connected, the other via two Lines also with the hydraulic fluid reservoir or the fluid collecting container connected is.

In order to quickly apply the required to the cylinder Ensure hydraulic fluid volume, point the liquid lines between cylinder and hydraulically operated valve or between cylinder and hydraulic fluid reservoir a correspondingly large inside diameter, furthermore it is hydraulically operated Valve designed so that it is at least in the connecting the two said lines Switching position releases a correspondingly large cross-section. From the above already discussed in connection with the hydraulic fluid loading of the cylinder 29 For reasons, an electro-magnetic main valve is not provided, but instead the main valve is designed as a hydraulically operated valve with a smaller volume electromagnetically operated pilot valve is connected upstream. Also from the already given reasons, the pilot valve and main valve are each designed as a ball seat valve.

In order to disengage the clutch 7 quickly, but slowly To ensure re-engagement is in the fluid line between the clutch actuator cylinder and the hydraulically operated main valve a one-way throttle switched on, which a large cross-section towards the cylinder, but in the opposite direction of flow only releases a small cross-section.

Claims (13)

Claims 1. Device for switching multi-stage gear change gears, especially for trucks, with an electrical or electronic control part is provided, which by hand and / or automatically depending on the engine load and speed as well as the effective gear stage is triggered or starts, and the automatic disengagement of the level that has been effective, the subsequent creation of the synchronous operation of the one to be brought into engagement for the selected stage, to the mediation different gear ratios axially displaceable gears or toothed switching elements and the engagement of the same in one another, preferably including the uncoupling of the drive motor before said disengagement, which if necessary after this disengagement, there is a separate rapid revolution deceleration or acceleration one of the drive motor upstream of the gearbox and the one downstream of the gearbox The gear part of the shaft to be driven is disengaged with each other with each stage change gear part pair to be brought into engagement to achieve its synchronous operation and re-coupling after said engagement, controls, wherein further a pressurized fluid source with fluid collecting container and adjusting cylinder are provided, their pistons each with one of the to be moved when changing levels Gear parts are connected, and which for abruptly pressing in the gears or switching elements when their synchronous operation occurs and the load is applied or relieved of the respective with one or of one sufficiently large to move it Hydraulic fluid volume in each case through at least one hydraulically operated main valve with a large passage cross-section and pipes with a large internal diameter. with the source and the collecting container connected to which main valve through an electromagnetic pilot valve with a small flow area and smaller the control part of the connected excitation coil is controlled, and finally if necessary, actuate a hydraulic actuating cylinder with electro-magnetically Valve assembly for clutch actuation and a device for accelerating or decelerating of the free-running gear part of the in synchronous operation with a stage change bringing pair of gear parts are provided, according to patent ... (patent application P 19 30 046.0-21), characterized in that a hydraulic adjusting cylinder (29) provided with at least one main valve and one pilot valve (42; 43 or 52; 53) is, which with an axially displaceable and rotatable selector shaft (24) to their sudden twisting cooperates by a second hydraulic actuating cylinder (29 ') is axially adjustable according to the step change to be made. 2. Apparatus according to claim 1, wherein each axially movable gear or switching element of the transmission in two different gear stages in one each other toothing is engageable, characterized in that the. Adjusting cylinder (2g) is designed as a three-position sylander for rotating the selector shaft (24) and a piston (26) which in the cylinder (29) in two end positions and one Middle position is movable, in which cylinder (29) three lines (31, 40, 41) large Mouth inner diameter, one of which with the hydraulic fluid source (34) and the other two with a hydraulically operated 2-position 3-way main valve each (42 and 43) are connected, which two main valves (42; 43) each also to the pressure fluid source (34) and to the fluid collecting container (38) are connected via lines (44; 45 or 46; 47) with a large inner diameter and release a large cross-section in each switching direction as well by an electromagnetic 2-position 3-way valve (52 or 53) with a small, the excitation coil connected to the control part are controlled, which two pilot valves (52; 53) each release only a small cross section in each switching direction and on the one hand with the actuating cylinder (50 or 51) one of the main valves (42; 43), on the other hand with the pressure fluid source (34) and the fluid collecting container (38) via lines (54; 55 or 56; 57) of smaller inner diameter in connection stand, the main valves (42; 43) are controlled so that in the central position of the piston (26) two of the lines opening into the cylinder (29) with the pressure fluid source (34) are connected, while the third line with the collecting container (38) in Connection is jn one end position of the piston (26) with all three lines the pressure fluid source (34) have connection, and in the other end position of the Piston (26) only one of the lines with the pressure fluid source (34) and the remaining two lines are connected to the collecting container (38). 3. Apparatus according to claim 2, characterized in that the cylinder (29) has an annular stop (30) which the cylinder (29) in a front Section in which the first connected to the shift shaft (24) to be rotated Piston (26) runs, and divided into a rear section in which a second Piston (27) runs, which when it rests on the ring stop (30) with its piston rod so far into the front ZylInderabschnitt that the at the free end of this The first piston (26) resting against the piston rod is in the central position in which it is the same distance from the ring stop (30) and from the front inner face of the cylinder (29) is removed, the rear ZylInderabschnitt is at least so long that when the second piston (27) rests on the rear inner face of the cylinder (29) the free egg of his Piston rod just outside the front Cylinder portion is, also the effective surface of the first piston (26) its side facing the second piston (27) is larger than that of the front The end face of the cylinder (29) is facing, and continues to be of the three lines (31; 40; 41) of large internal diameter opening into the cylinder (29) the two lines (40; 41) in or near the rear inner face of the cylinder (29) or in open near the ring stop (30), while the main valve-less line (31) in or near the front inner face of the cylinder (29) m-ündet. 4. Apparatus according to claim 2, characterized in that the adjusting cylinder (29) designed as a rotary piston actuating cylinder for rotating the selector shaft (24) is, which has a central rotary sleeve, which with the selector shaft to their Rotation is connected, and to which a first segment piston is attached, wherein a second segment piston is provided, which between two stop positions is rotatable, namely between one of the end position of the first segment piston distant end position and one of said end positions of the first segment piston closer middle position. 5. Device according to one of the preceding claims, characterized in that that in the lines between the pressure fluid source (34) and the front as well Main valves (52; 53 or 42, 43) an electromagnetically operated 2-position 3-way valve (32) is inserted, which is also attached to the liquid collecting container (38) is connected via a further line (39) so that in one switching direction of the valve (32) the pressure fluid source (34) and in the other switching direction the The liquid collecting container (38) to the lines to the and main valves and the cylinder (29) is connected. 6. Device according to one of the preceding claims, characterized in that that the electromagnetically operated pilot valves (52; 53) and the hydraulically operated Main valves (42; 43) but at least the pilot valves (52; 53) as seat valves, are preferably designed as ball seat valves. 7. Device according to one of the preceding claims, characterized in that that the piston rod (25) of the actuating cylinder (29) for turning the selector shaft (24) is designed as a rack which meshes with a pinion (24 ") that meshes with the shift shaft (24) is connected to prevent rotation, but is axially displaceable or that the rotary sleeve of the rotary piston actuating cylinder with the selector shaft (24) is torsion-proof, but is connected axially displaceably. 8. Apparatus according to claim 7, characterized in that the switching shaft (24) has a wedge-like finger (2ru '), which in every axial position of the Shift shaft (24) on shift linkage (21; 22; 23, 23 ', 23 ", 23' '') of another transmission gear (20 ') or toothed gear shift member (18; 19) engages. 9. Device according to one of the preceding claims, characterized in that that the switching shaft (24) in three axial positions by a hydraulic actuating cylinder (29 ') is displaceable, which is designed as a three-position cylinder and a Piston (26 ') which in the cylinder (29') in two end positions and a central position is movable, in which cylinder (29 ') three lines (31'; 40 '; 41') open, of which one with the pressure fluid source (34) and the other two with each an electromagnetic 2-position 5-way Y-valve (42 'resp. 43 ') are connected, which two valves (42'; 43 ') are also connected to the 1) fluid source (34) and connected to the liquid collecting container (38) and from the control unit are controlled so that in the central position of the piston (26 ') two of the in the cylinder (29 ') opening lines (31'; 40 '; 41') are connected to the pressure fluid source (34) areX while the third line is connected to the collecting container (78), in one end position of the piston (26 ') all three lines (31'; 40 '; 41') with the Have pressure fluid source (34) connection, and in the other end position of the piston (26 ') only one of the lines (31'; 40 '; 41') to the pressure fluid source (34) and the other two lines are connected to the collecting container (38). 10. Apparatus according to claim 9, characterized in that the cylinder (29 ') has an annular stop (30') which the cylinder (29 ') into a front Section in which the one connected to the shift shaft (24) to be axially displaced first piston (26t) runs, and divided into a rear section in which a second piston (27 ') runs, which when it rests on the ring stop (30') with its The piston rod protrudes so far into the front cylinder section that the free one The end of this piston rod, the first piston (26 ') lying against the rod is in the central position, in which it is equidistant from the ring stop (30 ') and from the front inner face of the cylinder (29 ') is removed, the rear cylinder portion at least is so long that when the second piston (29 ') rests on the rear inner end face of the cylinder (29 ') the free end of its piston rod just outside the front Cylinder portion is, also the effective surface of the first piston (26 ') its side facing the second piston (27 ') is larger than that of the front Flow area of the cylinder (29 ') facing side, and where furthermore, of the three lines (31 '; 40'; 411) opening into the cylinder, the two lines (40 '; 41') each equipped with a valve (42 'or 43') in or in the vicinity of the rear inner end face of the cylinder (29 ') or in the vicinity of the Ring stop (30 ') open out, while the valveless line (31') in or in the Near the front inner face of the cylinder (29 ') opens. 11. Apparatus according to claim 9 or 10, characterized in that into the lines (31 '; 44'; 45t) between the pressure fluid source (34) and the Valves (42 '; 43') an electromagnetically operated 2-position 3-way valve (32) is switched on, which is also connected to the liquid collecting container (38) is connected via a further line (39) so that in one switching direction of the valve (32) of the pressure fluid source (34) and in the other switching direction the liquid collection container (38) to the lines (31 '; 44'; 45 ') to the Valves (42 '; 43') and the cylinder (29 ') is connected. 12. Device according to one of claims 9 to 11, characterized in that that the valves (42 '; 43') are designed as seat valves, preferably as ball seat valves are. 13. Device according to one of the preceding claims, characterized in that that the switching shaft (24) cooperates with switches (82 '; 83'; 84 '), which respectively assigned to another axial position of the selector shaft (24) and from the selector shaft (24) when the respective axial signal is reached to send a signal to the Control part can be actuated.