DE3447939A1 - Hydraulic control valve system for a multigear, automatic, hydrokinetic-mechanical gearbox for motor vehicles - Google Patents

Abstract

In a hydraulic control valve system for a multigear, automatic, hydrokinetic-mechanical gearbox for motor vehicles with a torque converter with a lockup clutch and a gearbox with three planetary wheel systems, which provides four forwards gears, one of which forms an overdrive, a line pressure LINE being produced by a pressure medium pump by way of an oil pressure regulating valve and an oil pressure booster valve as a function of a throttle pressure valve supplying pressure signals corresponding to the torque requirement and of a centrifugal governor valve supplying pressure signals corresponding to the speed of travel, which line pressure is fed by way of a manual selector valve to a plurality of control valves, which in addition are influenced by the pressure signals of the throttle pressure valve and of the centrifugal governor valve, in order to bring about the automatic gear shifts, comfort-promoting control valves such as a overrun-mode control valve and a torque-mode control valve being provided for the particularly important upward gear shifts from 2 to 3 and downwards gear shifts from 3 to 2 in different operating conditions, further comfort-promoting control valves for different operating ranges are assigned to the 2-3 control valve in order to improve especially the performing of 3 to 2 downwards gear shifts in different operating conditions.

Description

Hydraulic control valve system for a multi-course,

self-shifting, hydrokinetic-mechanical change gear for motor vehicles The invention is based on a hydraulic control valve system for a multi-speed, automatically shifting hydrokinetic-mechanical change gear for motor vehicles of the type explained in the preamble of claim 1.

From DE-OS 22 27 555 the applicant is already a hydraulic Control valve system for a multi-course, automatically switching hydrokinetic-mechanical Change gear for motor vehicles known, in which the various elements of a Planetary gear change gear, consisting of an auxiliary set and a Simpson set, via piston or servo devices, starting from a manual selector valve via a main pressure regulating valve that controls the line pressure and as a function of control valves responding to the torque demand or the driving speed as well as the corresponding piston or servo devices and the corresponding Shift valves assigned to gear steps were actuated, whereby for special operating ranges special valves were provided to e.g. B. different downshift functions for a 4-3 downshift to steer, depending on whether the driver is driving the vehicle runs in overrun mode or signals a torque request.

In the known control valve system, both the 2-3 switching valve as well as the 3-4 switching valve each assigned two comfort control valves, the especially the important 2-3 and 3-4 upshifts or the important 3-2 and Control 4-3 downshifts differently, depending on whether the vehicle is in push mode running or the driver signals a torque request. These respectively Two comfort control valves assigned to a switching valve must have a relative widen Overlap the range of travel speeds and throttle valve positions, which means a rather sluggish response of the gearbox to the torque request results from the driver.

The object of the invention is to provide a hydraulic control valve system to improve this type in such a way that it is possible for a multi-course, automatically switching, hydrokinetic-mechanical change gear e for motor vehicles is applicable, such as it in the parallel patent application P 34 17 703.5, filed on May 12, 1984 is described by the applicant, and that is different from that in the above-mentioned laid-open specification The change transmission explained essentially differs in that on the one hand a converter bridging clutch is provided and, on the other hand, the fourth forward gear is designed as a gentle cycle, modifying existing control functions are intended to improve the 3-2 band clutch torque requirement downshifts or 2-3 shifting upshifts as well as the control of the clutches to achieve the manual shift position selection according to "2" and the 3-2 torque demand downshift characteristic shift towards a more agile approach.

According to the invention, this object is achieved by in a hydraulic Control valve system according to the preamble of claim in the characterizing part of the features indicated are applied.

Because the additional comfort control valves are the 2-3 switching valve are assigned, can in the particularly wide driving speed range, which between about 20 and 120 km / h and in which both the 2nd gear and the 3rd gear is available, a more agile response of the gearbox to a torque request can be achieved by different subareas the individual comfort control valves assigned.

The invention is illustrated by means of one in the accompanying drawings Embodiment explained in more detail.

It shows: Fig. 1 a - g schematic diagrams of the multi-course, hydrokinetic-mechanical transmission with overdrive, with the in the different Gears effective transmission elements are highlighted in Fig. 2, a list the operating ranges set on the manual selector valve in the different Gears engaged or applied clutches and brakes Fig. 3 A, B, C and D an overall arrangement of the hydraulic control valve system with a plurality of known switching and control valves with their corresponding designations are provided, to which the reference numerals are added in brackets with which these Valves in the known DE-OS 22 27 555 are designated.

The additional control valves according to the invention or

the modified control valves are marked with a The grid is highlighted and the lines connecting the individual valves are marked with Letters and numbers are added to indicate the operating status the respective line which pressure leads Fig. 4 a switching characteristic of the hydraulic Control valve system in Fig. 3 Fig. 5 is a table from the known DE-OS 22 27 555 predetermined circuit logic Fig. 6 is a table of the inventive, extended circuit logic First, reference is made to Figures 1 and 2, from which the transmission structure and the actuated in the different gear steps Clutches and brakes are shown.

As can be seen from Fig. 1, the gear assembly consists of a nlotorantrieb E, which is connected to the pump part I of a hydrokinetic torque converter is drivingly connected. The turbine part T, with the interposition of the usual Stator part S is driven by pump part I, drives via a converter or drive shaft C the planet carrier Cl of a ballast set.

In addition, there is a lock-up clutch in the area of the torque converter LUCL provided, which can optionally be indented.

The ballast set has a sun gear S1, planet gears Pl and a Ring wheel Rl on. The sun gear Sl is connected to a brake drum, which is of a Brake band B1 is included and at the same time forms part of a clutch CLl. The ring gear R1 forms the output of the ballast set and has a center shaft M drivingly connected.

This was communicated to the auxiliary set via the drive shaft converter shaft C. Torque can on the one hand by engaging the clutch CL1, which the sun gear S1 connects with the planet carrier Cl, are transmitted in both directions of rotation, or is in torque mode in 1st, 2nd and 3rd gear by locking an between the planet carrier Cl and the center shaft M arranged overrunning clutch OWCl in Transfer driving direction of rotation.

The center shaft M forms the input link for a well-known Simpson sentence, which in the usual way has two input clutches, of which the clutch CL2 the interconnected sun gears S2 and S3 can drive and of which the Clutch CL3 can drive the ring gear R2. The planet carrier C2 and the ring gear R3 are drivingly connected to the output shaft 0 of the transmission.

A third brake B3 is provided to the planet carrier C3 in set both directions of rotation and in addition, another rear, second Overrunning clutch or brake OWC2 is provided to turn planetary carrier C3 into one Determine the direction of rotation.

From Fig. 2 are in the by the position of the manual selector valve selected shift positions in the individual gear steps engaged and actuated Clutches and brakes can be seen.

In the "P" switch position, corresponding to "Parking", there is no control. In this position, the engine speed is controlled by the converter and the drive shaft C routed to planet carrier C1. The freewheel inner ring pressed onto the planet carrier C1 of the overrunning clutch OWC1 passes over the freewheeling clamps that lock in the direction of engine rotation the torque on the freewheel outer ring, which is formed by the center shaft M. the Center shaft M in turn drives the forward clutch body in a rigid connection. The power flow ends here, as both the forward clutch CL3 and the reverse and Direct clutch CL2 are released. In addition, the output shaft 0 is still through blocks a parking mechanism that engages below about 6 km / h.

In the shift position "R", the reverse gear, is in the upstream set the clutch CL1 is engaged and the overrunning clutch OWC1 locks, while in the Simpson set the clutch CL2 and the brake B3 are actuated. The power flow in the front area up to the forward clutch body is equal to the shift position "P". About the closed reverse gear and direct gear clutch CL2 and the one with the Clutch drum Permanently connected drive bell, the connected sun gears S2 and S3 are driven. Since the rear drum and thus the Planet carrier C3 of the third planetary set is held, the ring gear R2 rotates and the output shaft O in the reverse direction of rotation at the reduced speed the reverse gear ratio of 2.11: 1.

In the switch position "N" corresponding to "Neutral" there is no control. The power flow in the switch position "N" is the same as in "P", that is, it finds no downforce. Here, however, the output shaft is not blocked.

In the "DE" shift position, the automatic range in which the gearbox automatically according to the torque requirement and the driving speed between shifts between gears 1 to 4, the lower three forward gears are the first gear set blocked by the action of the overrunning clutch OWC1 and in the Simpson set are in 1.

In 2nd gear, clutch CL3 and overrunning clutch OWC2 are actuated. In 3rd gear, the brake B2 and the clutch CL3 are operated, and in 3rd gear, the clutch CL2 and actuates clutch CL3.

In addition, the converter lock-up clutch is in 3rd gear LUCL indented. The converter lock-up clutch LUCL is also in 4th gear engaged and the applied brake B1 takes effect, the means that it is not locked but translated in relation to the toothing (e.g. Currently 0.75: 1).

The Simpson set remains in the same state as in 3rd gear, i.e. H.

the two clutches CL2 and CL3 are engaged.

In detail, the power flow in the individual gears runs as follows: "DE" - 1st gear traction mode The power flow in the front area up to the forward clutch body is equal to position "P". Pressurization causes the forward clutch to operate CL3 engaged and the ring gear R2 of the second planetary set in the direction of engine rotation driven. The planetary gears P2 are driven in the same direction by the ring gear R2. As a result, the sun gear S2 is driven in the opposite direction of rotation. This sun gear S2 drives the ring gear R3 via the planetary gears P3 of the third planetary set, which then rotates again in the direction of motor rotation. The rear planet carrier supports while doing this on the overtaking brake OWC2.

The combination of the planetary sets connected in series results in 1st gear has a ratio of 2,474: 1, whereby the torque is also common from the planet carrier C2 of the second and from the ring gear R3 of the third planetary set is transmitted to the output shaft O.

DE - 1st gear overrun mode In overrun mode, the rear overtaking brake is activated OWC2 rolls over so that there is no through drive to the converter and the engine is at idle speed can fall off. The front overrunning clutch OWC1 would also roll over, but this no longer applies.

DE - 2nd gear traction mode The power flow in the front area up to Ring gear R2 of the second planetary set is the same as 1st gear in shift position "DE".

In addition to the forward clutch CL3 is pressurized the second brake B2 is applied to the contact side of the servo of the 2nd gear belt and thereby the drum of the reverse and direct gear clutch CL2 and via the one rigidly connected to it Drive bell braked the sun gear S2 of the second planetary set. The one in the planet carrier mounted planetary gears P2 des second planetary gear set are from Ring gear R2 driven and rotate with the planet carrier C2 around the held Sun gear S2, the planet carrier C2 in rigid connection with the output shaft rotates with a gear ratio of 1.47: 1.

DE - 2nd gear overrun mode In overrun mode, the output shaft drives 0 to the planet carrier C2 of the second planetary set, which is thereby with its Planet gears P2 rotates around the held sun gear S2 and via the ring gear R2 and the forward clutch CL2 drives the axle shaft.

The power flow ends at the front first overrunning clutch OWC1, the is rolled over in the thrust direction. This can cause the engine speed to drop to idle.

DE - 3rd gear traction mode The power flow in the front area up to Ring gear R2 of the second planetary set is the same as 1st gear in shift position "DE".

The change from 2nd to 3rd gear is characterized in that by Pressurization of the release side of the servo of the 2nd gear band the second brake B2 releases the reverse and direct gear clutch by applying pressure CL2 closes, which then drives the sun gears S2 and S3 via the drive bell will. Since now from the second planetary set ring gear R2 and sun gear S2 with input shaft speed are driven, the planet carrier C2 drives the output shaft 0 with the same Speed In addition, the converter lock-up clutch is also activated after the 2-3 shift LUCL applied so that the converter works without slippage. This is in 3rd gear a real 1: 1 ratio is achieved.

DE - 3rd gear overrun As in 2nd gear in position "DE" the front overrunning clutch OWC1 is overrun and the engine can idle fall off.

DE - 4th gear traction mode The power flow in the rear area from the Center shaft M is the same as in 3rd gear in position "DE". In addition, through Pressurization of the application side of the servo of the first brake B1, the first brake B1 actuated, whereby the brake drum and its connection to the sun gear S1 this is recorded. As already described at the beginning, this rotates the Center shaft as output in rigid connection with the ring gear R1 in the transmission ratio from 0.75: 1.

DE - 4th gear overrun In contrast to gears 1, 2 and 3 in In the "DE" position, the first overrunning clutch OWC1 is not overrun because the sun gear S1 is also held in thrust and thus the planet carrier C1 is held by the center shaft M is driven. This means that the engine always rotates at the same speed as the vehicle speed in connection with the drive train ratio. It finds the so-called Engine braking instead.

In switching position "D", the automatic range in which only between the gear steps 1 to 3 are shifted, are again those explained above Clutches and brakes actuated, with the releasing in push mode Overrunning clutch OWC1 in the upstream set results in a desired freewheeling effect. With position "D" made it possible to drive the vehicle without actuating the KD to reach the highest speed.

In the shift position "2" is the power flow and the transmission ratio in train operation the same as described in position DE - 2nd gear. In contrast to the In positions "DE" and "D", the vehicle starts directly in 2nd gear and does not shift high. This is advantageous when starting off on soft, sandy or smooth surfaces and when going downhill. The engine is braked by applying the first clutch CL1 reached. When selecting switching position "2", it switches at high speeds the gearbox into 2nd gear depending on the speed.

In the switching position "1" is the power flow and the transmission ratio in train operation the same as described in position DE - 1st gear. In addition, over the rear brake band B3 held the reverse drum. As in this position too the first clutch CL1 is applied, engine braking takes place. At the Selecting shift position "1" at high speeds shifts the transmission depending on the speed in 1st gear. An upshift from 1st gear takes place not held.

This switching position is therefore particularly suitable for driving downhill heavy load or steep incline.

From Figs. 3 A, B, C and D is the overall arrangement of the hydraulic Control valve system can be seen that the functions of applying and releasing the couplings and braking of the change gear according to FIG. 1 in the manner explained in connection with FIG Sequence controls. In FIGS. 3 A, B, C and D are here the reference numerals from the prior art mentioned in the introduction to the description Application DE-OS 22 27 555 taken over known valves and put in brackets been.

The manual selector valve, which can be manually switched to one of seven switching positions can be brought, identified by the symbols P, R, N, DE, D, 2 and 1 are, is provided in Fig. 3 D with the reference number (300).

The control collars of the manual selector valve (300) are accordingly the selected switching position pressurizes different lines, where is indicated by the inserted letter and number combinations, in which switching position the corresponding line carries pressure or which pressure she leads. Guides one and the same line in different switching positions or operating ranges different pressures, these are each marked by a Slash indicated separately from each other. To designate the respective line the corresponding pressure designations are put in brackets.

Although actually only three different ones in the hydraulic control valve system Pressures, the line pressure "LINE", the torque request or throttle pressure "TV" and the vehicle speed or centrifugal governor pressure "GOV" are present each of these pressures was given a new name as soon as it was replaced by a corresponding one Valve can be released or blocked or changed or modulated.

The one required for the hydraulic control valve system to function Pressure medium is provided in a known manner by a pump, which generates the so-called system or line pressure LINE as soon as the combustion engine is activated the motor vehicle is running.

The level of the line pressure LINE is determined by a pressure regulating valve (202) and an oil pressure booster valve (214) as a function of pressure signals controlled, which show the level of the torque requirement or the driving speed or is determined by the switch position "R".

For this purpose, the transmission is in a known manner with a torque requirement detecting throttle pressure valve (230) provided, the one of the line pressure Torque request proportional pressure signal, also called throttle pressure TV, generated, which is necessary for influencing various switching valves is.

The transmission also indicates the driving speed in a known manner detecting centrifugal governor valve (144), which from the line pressure one of the Vehicle speed proportional pressure signal, also centrifugal governor pressure GOV called, generated, which also acts on the various switching valves, to effect the automatic switching processes.

The hydraulic control valve system has a known manner Number of switching valves on, depending on the acting line pressure LINE, the corresponding spring forces, the throttle pressure TV and the centrifugal governor pressure GOV initiate the application and release of the corresponding clutches and brakes.

So a 1-2 switching valve (428) is a 2-3 switching valve 450 = approximately (446) and a 3-4 switching valve 550 = approximately (334) are provided in a known manner control the upshifts.

There are also corresponding 3-2 comfort control valves for different Operating ranges, for example for pushing operation (276) or for torque operation (278) is provided (see Fig. 5).

In addition, an overrun booster valve (266) is used Increasing the line pressure arranged in overrun mode. Accumulator valves (166 and 570) are arranged to discharge the pressure medium from the release side of the servos to control for B2 and B1 and a correspondingly dampened application of the brake bands to reach.

There is also a torque request valve or a kick-down valve (314) is provided, depending on a maximum actuation of the accelerator pedal and the respective speed a forced downshift from the engaged gear into one of the lower gears or delaying or preventing an upshift.

Since the influence of the throttle pressure TV at high driving speeds would lead to a further increase in the line pressure LINE is a shut-off valve (226) is provided, which is influenced by the vehicle speed pressure GOV.

In the following, the new valve arrangements according to the invention are now or according to the invention modified valve assemblies explained in the drawing are highlighted by a background grid.

The desired torque converter lock-up control during a Operation in 3rd and 4th gear is via a torque converter lock-up clutch control valve 500 and a bridging clutch switching valve 520 that interacts with this achieved. The control valve 500 consists essentially of a spring-type 502 loaded valve body 504, the essentially three control collars 506, 508 and 510, which are arranged so that in the in Fig.

3 position shown, in which the converter clutch LUCL is open, the converter inlet pressure CC to the converter via the line (CC / EX) in front of the lock-up clutch piston is fed and via the open lock-up clutch in the converter trilock area arrives and from there as converter return CDC via the line (CDC / LUC) and the control valve 500 flows through the line (COOLER).

In the second, upshifted position, in which the converter clutch LUCL is closed, line pressure LINE flows as lock-up pressure LUC over the line (CDC / LUC) in the converter trilock area during the room in front the lock-up clutch piston as converter return EX via the line (CC / EC) is derived to the oil sump. The converter inlet pressure CC from the line (CC / COOLER) flows directly to the cooler via the line (COOLER).

The control valve 500, in particular its spring 502, is like this here designed so that it is also effective as a function of the level of the line pressure can be, namely of the type that whenever in driving mode in 3rd and 4th gear and With the converter lock-up clutch engaged, the accelerator pedal is released, the converter lock-up clutch is disengaged because the throttle pressure signal drops sharply when the accelerator pedal is released and thus the line pressure is reduced to a value that of the spring 502 switch down the valve body 504 allows. Thus, in the so-called Overrun operation of the motor vehicle prevents the engine from revving.

The control valve 500 is speed-dependent in normal operation controlled via a lock-up clutch switching valve 520, which consists of a valve body 522 consists of four control collars 523, 524, 525 and 526 and a spring 527 is held in the installation position. The lower end of the valve body 522 acts The centrifugal governor pressure GOV is used here, and a control pressure acts on the control collar 525 TDC / KD / 2/1 / R-I and a modulator valve 530 acts at its upper end, which consists of a valve body 531 with a control collar 532 and a spring (533) and on the one hand from the throttle pressure TV / TVB and control pressures KD / 2/1 / R-I and MOD / KD / 2/1 / R-I is applied.

The valve body 522 of the torque converter lock-up clutch shift valve is located 520 in the position shown in Fig. 3, line pressure becomes LINE across the gap between the control collars 528 and 526 as a lock-up clutch pressure LUC to the torque converter lock-up clutch control valve 500 out and amplifies the force of the spring 502, which the valve body 504 holds against the line pressure acting at the lower end LINE downwards and this keeps the torque converter bridging clutch disengaged. As soon as at increasing driving speed the centrifugal governor pressure GOV increases and this counteracting control pressures TD CI KD / 2111 R-I are overcome, the valve body 522 switched high and the line pressure LINE locked. Through this acts at the upper end of the torque converter override clutch control valve only the force of the spring 502 on the valve body 504, which is sufficient high line pressure LINE, in normal operation always to upshift the valve body 504, whereby the torque converter lock-up clutch is engaged. As already explained, the line pressure is only when the accelerator pedal is released not high enough to upshift the valve body 504 against the force the spring 502 to effect.

The lock-up clutch pressure LUC of the switching valve 520 acts here Via a ball change valve 530 to the control valve 500.

Optionally, a lock-up clutch inhibiting pressure can also be used at the same point LU / INH, which is passed by a lock-up clutch prevention valve 540 which is electrically or microprocessor controlled by a solenoid 542 is actuatable.

This means that an engagement can be made depending on other operating conditions the torque converter lock-up clutch can be prevented or the engaged Clutch can be opened.

In the valve bore of the lock-up clutch switching valve 520 a 3-2 torque mode switching valve 740 is arranged. The 3-2 torque mode switching valve 740 consists of a valve sleeve 742 arranged in the valve bore, in which a valve body 744 is arranged, which is pressed upwards via a valve spring 745 will. The valve body 744 has four control collars 746, 747, 748 and 749.

The 3-2 torque mode shift valve 740 enables upon a torque request below the kick-down area a 3-2 circuit to e.g. B. the required Provide acceleration for an overtaking process.

The 3-4 shift valve required for a 3-4 upshift 550 consists of a valve body 551 with three control collars 552, 553 and 554 and a valve spring 555 and is here compared to a conventional switching valve of this Art (334) different in that it deals with a hydraulic forced locking of the switching valve when the manual valve is in position D, the upshift can prevent 4th gear. The control pressure 3 acting over acts here the line (KD / 3/2 / 11R). A modulator valve acting on the 3-4 shift valve 550 556 has two effects, depending on the throttle pressure TV / TVB Springs and the centrifugal governor pressure acting at the lower end of the 3-4 switching valve 550 GOV an automatic upshift into 4th gear, provided that the manual selector valve is in the DE position.

To avoid incorrect operation of the manual selector valve at high driving speeds To prevent dangerous engagement of reverse gear is a reverse gear prevention valve 580 is provided, which is above a defined speed of z. B. 16 kmlh, when the switch position "R" is engaged on the manual selector valve, it is released or applied the shift elements required for reverse gear, the second clutch CL2, the first clutch CL1 and the third brake B3 prevented. The reverse gear prevention valve 580 has for this purpose a valve body 582 which, against the pressure of a spring 584 about the centrifugal governor pressure GOV acting at one end at high Driving speed is held in its locked position until the defined The speed is not reached and the gear is engaged can.

There is also the engagement for switching position "1" on the manual selector valve (300) the third brake B3 is required, when the switch position "1" is selected the manual valve (300) forced the reverse gear prevention valve 580 made ineffective.

In a similar way, when the manual selector valve (300) is inserted to switch position "2" or "1" if the driving speed is too high, first Switching on the selected gear can be prevented until the vehicle speed has fallen below a certain value, which means that the desired circuit allows.

A similar one essentially to a conventional 2-3 switching valve (446) 2-3 switching valve 450 in a modified version has a valve body 451 five control collars 452, 453, 454, 455 and 456, with the pressure on control collar 455 2/1 / R-I and on the control collar 456 attack the pressure MOD / RD / 2/1 / R-I while on the other hand, on the control collar 452, the centrifugal governor pressure (GOV) attacks to at inserting the manual selector valve into switching position "2" when the vehicle speed is too high to prevent actuation of the corresponding switching elements until the speed of the vehicle below a predetermined value, e.g. B. has dropped 118 km / h and the 2nd gear can be engaged.

A D2 switching valve (429) known per se acts with one per se known 1-2 switching valve (428) together. The D2 switching valve (429) has a Valve body (430) with six control collars (431 to 436), with the control collar (431) the pressure MOD / KD / 2/1 / R-I attacks, on the control collar (432) the pressure 1 / R-I and on the control collar (434) the pressure D / 3/2/1 attacks, while on the other side on Control collar (431) the centrifugal governor pressure GOV attacks, so that when you insert of the manual selector valve in switching position "1" if the driving speed is too high first the switching elements for inserting the 2nd

Ganges operated and only after the driving speed of the vehicle below a certain value, e.g. B. 60 km / h has dropped, the desired circuit takes place in 1st gear.

For the coordination of the very important 3-2 load change downshift a new valve concept was developed, which compared to the previous four operating areas has been expanded to eight operating ranges for better calibration, whereby in principle the concept of throttling the release process of the second clutch CL 2 and the Application process of the second brake B2 was retained.

In the known valve arrangement according to DE-OS 22 27 555 of the applicant a normal 2-3 switching valve (446) works together with two 3-2 comfort control valves, a 3-2 push mode control valve (276) and a 3-2 torque mode control valve (278).

This known valve arrangement made possible according to that shown in FIG Switching logic coordinated 3-2 switching operations in four operating ranges, namely with one manual switching initiated via the manual selector valve in push mode, at an automatic shift in push mode, in the case of a kick-down actuation forced shift and one caused by a moderate torque requirement Circuit.

In contrast, a normal one acts in the valve arrangement according to the invention 2-3 switching valve (446) in addition to a 3-2 overrun control valve 600, which roughly corresponds to the known valve (276) and a 3-2 kick-down switching valve 640, which roughly corresponds to the known valve (278) with three additional 3-2 comfort control valves together. These additional 3-2 comfort control valves are a 3-2 torque mode control valve 620 as well as a 3-2 kick-down control valve for the 2nd gear servo B2 660 and a 3-2 Kick-down control valve for the 3rd gear clutch CL2 680.

By operating the according to the switching logic in FIG Valve assembly according to the invention are matched 3-2 downshifts for eight different operating areas reached.

A 3-2 downshift is characterized in that the reverse gear and the direct gear clutch CL2 released and the brake band for 2nd gear B2 applied The influencing of the downshift comfort is essentially based on the fact that the displaced oil from the disengaging clutch CL2 and from the release side of the applied Pistons of the servo of the brake B2 via different valves and by different large throttle openings can flow off at different speeds. The 3-2 downshift can be divided into three general areas: DE-3-2 Downshift in overrun mode During overrun, the 3-2 overrun control valve 600 remains in its position shown in FIG 3 installation position shown. As a result, the discharge pressure of the 2-speed servo ISR ACC flow off via the duct (ISR ACC EX) via the throttle point LTV. The drain pressure of the coupling CL2 HC REL can flow uncalibrated via the channel (HC REL EX) DE-3-2 Downshift in torque demand mode TD In torque demand mode is the one acting on the lower end of the 3-2 coasting control valve 600 Throttle pressure TV so high that it switches up the valve body against the force of the spring This causes the discharge pressure of the 2-speed servo to flow at low speed ISR ACC and the discharge pressure of the clutch CL2 HC REL together and are depending on the driving speed that is applied via the regulator pressure GOV to the lower End of 3-2 torque mode control valve 620 acts either through the throttle point TDl or the throttle point TD2 derived. Shifts at higher driving speeds the regulator pressure acting on the lower end of the 3-2 kick-down switching valve 640 GOV this valve around, reducing the discharge pressure of the clutch CL2 HC REL and the discharge pressure of the 2nd gear servo ISR ACC must be separated again.

The discharge pressure of the clutch CL2 íL-IC REL is then via the 3-2 CL2 kick-down control valve 680 depending on the driving speed Throttling points HC KD1 or HC KD2 discharged while the discharge pressure of the 2nd gear servo ISR ACC can flow off via throttling points ISR KD 1 or ISR KD2.

EN-3-2 Downshift in kick-down mode Travel speed the 3-2 push mode control valve 600, the 3-2 torque mode control valve 620 and the 3-2 kick-down switching valve 640 switched up.

The 3-2 CL2 kick-down control valve 680 and the 3-2 B2 kick-down control valve 660 also switch depending on the driving speed and thereby direct the drain pressure of clutch CL2 HC REL via throttling points HC KD1 or HC KD2 or the discharge pressure of the 2nd gear servo ISR ACC via throttle points ISR KD1 or ISR KD2.

The two 3-2 kick-down control valves for the 2nd gear servo B2 660 and that for the 3rd gear clutch CL2 680 ensure that depending on the present Operating range, d. h, depending on the current driving speed with one through a kick-down actuation forced 3-2 downshifts a differently tuned The second clutch CL2 is released or the second brake B2 is applied, in which different throttling points ISR KD1, ISR KD2 and HC KD1 and HC KD2 are controlled will. These throttling points determine the outflow of pressure medium from the FIG. Second clutch CL2 that determines the gear or from the release side of the second gear servo B2 and thus the speed at which the brake band that determines 2nd gear is applied the second brake B2.

The 3-2 torque mode switching valve 740 provides a Expansion of the operating area, within it by a rapid but moderate Actuation of the accelerator pedal and the torque demand expressed thereby Downshift from 3rd gear to 2nd gear occurs using the 3-2 torque mode control valve 620 depending on the height of the vehicle speed-dependent acting at its lower end Centrifugal force glerdruch GOV controls different throttle points TD1 and TD2, which are for a coordinated release of the 3rd gear second clutch CL2 and application of the Brake band provides for the second brake B2 via the corresponding servo.

The switching characteristics of the hydraulic control valve system according to the invention can be seen clearly from the circuit diagram shown in FIG where on the abscissa the driving speed and on the ordinate the Accelerator pedal position is indicated and where the respective upshifts in full lines and the corresponding downshifts are shown in dashed lines Let us consider e.g. B. an accelerator pedal position in which a negative pressure of 30 KN / m² occurs. We move to the right on the horizontal line at 30 and can see that an upshift from 1st to 2nd gear takes place a little below 20 km / h per, the next upshift from 2nd to 3rd gear takes place at a little above 30 km / h, then the converter lock-up clutch is engaged at about 70 km / h and only at above 80 km / h shifting up to 4th gear causes hiking we turn left again on the same horizontal line so we can determine that at the dashed line marked with circles there is initially a disengagement the torque converter lock-up clutch takes place at around 64 kmlh and then at around 55 km / h the downshift from 4th gear to 3rd gear is carried out Downshift from 3rd gear to 2nd gear takes place at around 22 km / h and the next one Downshifting from 2nd gear to 1st gear always takes place at around 12 km / h.

From a comparison of the various horizontal lines and the from these cut upshift and downshift lines it is easy to see that with stronger torque demand, d. H. more depressed accelerator pedal and thus decreasing vacuum the corresponding upshifts to higher Driving speeds are shifted towards.

The ones at the top of the chart in short dashed and Shift lines shown in full lines relate to the so-called kick-down up or down. Downshifts that are only initiated when fully depressed the so-called kick-down valve is actuated on the accelerator pedal.

By indicated on the ordinate or the abscissa in dash-dot lines Areas labeled LTVC 600; TDC 620; KDT 640; ISR KDC and HC KDC 680 shows the speed ranges in which the different Comfort valves are effective.

Special emphasis was also placed on the very important 3-2 downshift which, as can be seen from the diagram, ranges between about 45 and 65 km / h can be caused by a torque request, but not the Corresponds to the full throttle or kick-down position of the accelerator pedal. In a similar way it is also a 4-3 downshift if the torque request is below the kick-down request possible.

The expansion of the hydraulic control valve system made according to the invention in connection with the improvements of the known valve functions enables on the one hand more agile shift characteristics when the driver requests torque and on the other hand, greater comfort as a result of the corresponding operating areas differently tuned downshifts.

Claims (2)

Patent claim hydraulic control valve system for a multi-course, automatically shifting hydrokinetic-mechanical change gear for motor vehicles, with a torque converter with a lock-up clutch and a gearbox with three planetary gear sets, the four forward gears, one of which is an overdrive forms and where from a pressure medium pump via an O1 pressure regulating valve and an oil pressure booster valve as a function of one of the torque request corresponding pressure signals delivering the throttle pressure valve and one of the driving speed Corresponding pressure signals delivering the centrifugal governor valve a line pressure LINE is created using a manual selector valve for a large number of switching and control valves is fed, which is also from the pressure signals of the throttle pressure valve and the centrifugal governor valve are influenced to the automatic circuits to effect, with the particularly important 2-3 upshifts and the 3-2 Downshifts for different operating ranges Comfort control valves, such as a push mode control valve and a torque mode switching valve are provided is, characterized in that in addition to a 3-2 overrun control valve (600) and a 3-2 kick-down switching valve (640) another three comfort control valves, a 3-2 torque mode control valve (620) and throttling points associated therewith (TDl and TD2) and a 3-2 kick-down control valve for clutch CL2 (680) and a 3-2 kick-down control valve for the 2nd gear servo B2 (660) with these assigned Throttle points (HC KDl and HC KD2 or ISR KD1 and ISR KD2) are provided.