JPH0756337B2 - Combined control device for automatic transmission - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite control device for slip control and creep prevention of a torque converter in an automatic transmission.

(Prior Art) In order to improve the performance and quality of an automatic transmission, a slip control device that controls relative rotation between input and output elements of the torque converter, that is, slip, and a drag phenomenon of the torque converter when the vehicle is stopped. That is, the number of creep prevention devices that prevent creep is increasing.

However, conventionally, these devices have conventionally been incorporated into an automatic transmission as individual devices.

(Problems to be Solved by the Invention) By the way, the slip control device and the creep prevention device commonly use the output torque of the torque converter as one of the control factors. If each automatic transmission is incorporated into the automatic transmission, the number of parts is increased, the hydraulic circuit is complicated, and the automatic transmission is expensive.

The present invention converts the output torque of the torque converter, which is a common control factor, into a pressure signal, and uses the pressure signal commonly in the slip control device and the creep prevention device, thereby making the parts common and simplifying the hydraulic circuit. It aims at solving the above-mentioned problem.

(Means for Solving the Problem) For this purpose, a combined control device for an automatic transmission according to the present invention includes a torque converter that is slip-controlled by adjusting the pressure of a lock-up control chamber in a transmission system and includes a starting friction element. In an automatic transmission that is fastened by fluid pressure and is capable of outputting rotation from the torque converter, torque pressure generating means for generating a torque pressure corresponding to the magnitude of output torque of the torque converter; A slip control device for supplying a lock-up control chamber to cause slip control of the torque converter, and a creep prevention action of the torque converter by supplying the torque pressure to a starting friction element instead of the fluid pressure. A creep prevention device is provided.

(Operation) The torque pressure generating means generates the torque pressure corresponding to the magnitude of the output torque of the torque converter, and the slip control device supplies this torque pressure to the lockup control chamber to perform the slip control of the torque converter. The creep preventing device performs the creep preventing action of the torque converter by supplying the torque pressure to the starting friction element instead of the fluid pressure.

By the way, since the torque pressure generating means is used for the slip control device and the creep prevention device, the number of parts of the automatic transmission can be reduced correspondingly, and the hydraulic circuit can be simplified, so that the cost of the automatic transmission can be reduced. Can be realized.

(Example) Hereinafter, the Example of this invention is described in detail based on drawing.

FIG. 1 shows an embodiment of the compound / control device of the present invention applied to an automatic transmission having two control devices, a torque converter slip control device 100 and a creep prevention device 101. In FIG. 1 shows a slip control type torque converter inserted in a power transmission system. The torque converter 1 mainly includes a pump impeller (torque converter input element) 2, a turbine liner (torque converter output element) 3, and a stator 4. It is assumed that the pump impeller 2 is drivingly connected to an engine crankshaft (not shown) via a converter cover 5 welded thereto, and is constantly driven by the engine crankshaft (not shown) during engine operation. Pump impeller 2
Further, a hollow pump drive shaft 6 is welded, and the pump 7 is constantly driven by this during operation of the engine.

The turpin runner 3 is provided with a turbine hub 9 rivetably fastened to the inner peripheral edge portion thereof, through which the turbine runner 3 is rotatably fitted on a sleeve 10, and the sleeve 10 is attached to a torque converter output shaft 11. It forms a part of the output shaft 11 by spline connection so as not to move in the axial direction. The turbine hub 9 and the sleeve 10 are integrally formed with flanges 9a and 10a that face each other and extend outward in the radial direction,
An annular plate 12 is arranged on the side of the flange 10a opposite to the flange 9a. The flange 9a and the annular plate 12 are integrally connected by a rivet 13, but the rivet 13 is loosely inserted into the corresponding hole 10c of the flange 10a to allow relative rotation between the flanges 9a and 10a, and thus between the turbine hub 9 and the sleeve 10. And The inner springs 15 and the outer springs 14 and inner springs 15 provided therein are arranged in the alignment windows provided in the flanges 9a, 10a and the annular plate 12, respectively, and are arranged in the circumferential direction of the flanges 9a, 10a and the annular plate 12. Be shorter than outer spring 14. The outer spring 14 normally keeps the relative rotation of the turbine hub 9 and the sleeve 10 at zero, and is compressed as the relative rotation increases, so that the inner spring 15
Serves to increase the spring constant of the outer spring 14 when the relative rotation exceeds a certain value.

A lockup clutch 16 is separately slidably fitted on the sleeve 10, and the lockup clutch 16 is isolated from the converter chamber 17 when the outer peripheral clutch facing 16a is pressed against the converter cover 5. A lockup control room 18 is created. Lockup control room 18
Is communicated with the outside through a hollow hole 11a formed in the torque converter output shaft 11. Further, the converter chamber 17 includes a hole 9b provided in the turbine hub 9 and a slit 10d provided in the sleeve 10.
And hole 10b, hole 11b provided in torque converter output shaft 11
The hole 9b and the slit 10d constitute a variable orifice 19 in which the opening S shown by hatching in FIG. 2 is changed by the overlap amount according to the relative rotational position of the turbine hub 9 and the sleeve 10.

The lockup clutch 16 further includes an annular member having an L-shaped cross section.
Tooth 20a and flange 10a formed by fixing 20 to the free edge
By meshing with the teeth 10e formed on the outer peripheral edge of
A lockup clutch (16) is drivingly connected to the sleeve (10) so as to be movable in the axial direction.

Further, the stator 4 of the torque converter 1 is placed on the hollow fixed shaft 22 via the one-way clutch 21, and annular passages 23, 24 are respectively provided between the shaft 22 and the pump drive shaft 6 and the torque converter output shaft 11. Set. The annular passage 23 guides the hydraulic oil from the oil pump 7 into the torque converter 1 through the circuit 25 and removes this operating oil from the annular passage 24 through the circuit 26. During this period, the pressure-holding valve provided in the circuit 26 is removed. 27 by the torque converter within 1, i.e. keep the converter chamber 17 at a constant pressure (converter pressure) P _C. In addition, hole 11b
Is connected to a circuit 29 having a fixed orifice 28, whereby the converter pressure P _C in the converter chamber 17 is varied.
A part is drained through 19, the holes 10b and 11b, the circuit 29, and the fixed orifice 28. Thus, a torque pressure P _T determined by the opening area difference between the variable orifice 19 and the fixed orifice 28 is generated, and this torque pressure changes according to the opening S of the variable orifice 19 (see FIG. 2). To do. By the way, the variable orifice 19 is displaced relative to the slit 10d in the direction of the solid line arrow in FIG. 2 when the transmission torque of the turbine runner 3, that is, the torque converter output torque is increased, so that the opening S is decreased and the torque converter is reduced. When the output torque decreases, the relative displacement occurs in the direction of the dotted line arrow in FIG.
Since the torque pressure P _T decreases as the opening degree of the variable orifice 19 decreases, this torque pressure eventually becomes, for example, the sixth torque with respect to the torque converter output torque.
It changes as shown. Therefore, the variable orifice 19 and the fixed orifice 28 form a torque pressure generating means for generating the torque pressure P _T corresponding to the magnitude of the torque converter output torque.

The slip control device comprises a first slip control valve 29 and a second slip control valve 30. The first slip control valve 29 has a spool 29b elastically supported by a spring 29b in the upper half position in the drawing, and in this spool position, the circuit 31 is connected to the circuit 32, and the spool 29b responds to the pressure in the chamber 29c. The circuit 31 is communicated with the circuit 33 when the lower half of the figure is reached. The second slip control valve 30 has a spool 30b elastically supported by a spring 30a in the upper half position in the drawing, and in this spool position, the circuit 34 is communicated with the circuit 31, and the spool 30b responds to the pressure in the chamber 30c. The circuit 34 is communicated with the drain port 30d when it is in the lower half position in the figure. Then, the circuit 32 is connected to the circuit 25 so that the converter pressure P _C can be conducted, the circuit 33 can be connected to the circuit 29 so that the torque pressure P _T can be conducted, and the circuit 34 can be conducted to the hollow hole 11a. A connection is made so that the lockup control pressure P _{L / u} towards the lockup control chamber 18 can be determined. In addition, the governor pressure P _G , which increases in proportion to the vehicle speed from the circuit 35, is introduced into the chambers 29c and 30c, respectively, and the governor pressure P _G becomes the seventh pressure.
The spool 29b is brought to the lower half position in the figure while the value is equal to or higher than the vehicle speed indicated by V ₁ in the figure, and the spool 30a is illustrated while the governor pressure P _G is the value equal to or higher than the vehicle speed indicated by V ₂ in the figure. It shall be brought to the position of the lower middle part.

The anti-creep device 101 comprises an anti-creep valve 36, which is inserted between the circuits 38, 39 for hydraulically actuating the forward clutch 37 of the automatic transmission. The forward clutch 37 corresponds to a friction element for starting, and while the driving vehicle desires to travel and the manual valve 41 is set to the forward travel (D, II or I) range via the manual lever 40, the circuit 42 to the circuit 39.
The line pressure P _L supplied to the engine is used as the source pressure to continue hydraulic operation.The creep prevention valve 36 is a circuit in a stopped state in which the engine throttle opening is below a very small set value and the vehicle speed is also below the very small set value.
The forward clutch operating hydraulic pressure P _{F / C} to the valve 38 is set to a value lower than the line pressure P _L from the circuit 39 to prevent creep.

Therefore, the anti-creep valve 36 has a spool 36b elastically supported by a spring 36a in the upper half position in the figure, and at this spool position, the circuit 38 is communicated with the circuit 33, and the spool 36b is connected to the chambers 36c, 3c.
The circuit 38 is connected to the circuit 39 when the lower half position in the figure is reached in response to the pressure in 6d. Then, the chamber 36c is connected to the circuit 35 so that the governor pressure P _G can be guided, and the chamber 36d can guide the slot pressure P _TH from the circuit 43 which increases in proportion to the engine throttle opening. Connect to circuit 43.

The operation of the above embodiment will be described below. First, in order to explain the operation of the slip control device 100, in the converter region A where the vehicle speed is V ₁ or less in FIG. 7, the governor pressure P _G corresponding to this vehicle speed is to the right of both the spools 29b and 30b as described above. However, these spools are held in the upper half position in the drawing by the springs 29a and 30a. Therefore, the converter pressure P _C from circuit 25
Through the circuits 32, 31 and 34 and the hollow hole 11a to the lockup control room 1
8, the lockup control pressure P _{L / u} in this chamber is made equal to the converter pressure P _c in the converter chamber 17. At this time, the lockup clutch 16 cannot be pressed against the converter cover 5 and does not transmit power, so that the torque converter 1 transmits power in a converter state in which slip is not limited at all.

In the slip control region B where the vehicle speed is between V _{1 and} V _{2 in} FIG. 7, only the spool 29b is set to the lower half position in the figure by the governor pressure P _G as described above. Therefore, the torque pressure P _T of the circuit 33 passes through the circuits 31 and 34 and the hollow hole 11a, and then the lock-up control chamber.
The lockup control pressure in this room has reached 18
P _{L / u} becomes the same as the torque pressure P _T. By the way, the torque pressure P _T
6 is lower than the converter pressure P _C in the chamber 17 as shown in FIG. 6, and the difference becomes larger as the torque converter output torque increases, so that the differential pressure of the lockup clutch 16 pressed against the converter cover 5 is increased. The fastening force increases as the output torque of the torque converter increases, and the slip of the torque converter 1 gradually decreases. And
The slip ratio e of the torque converter during the slip control.
Changes continuously as shown in FIG. 7, for example (e = 0.
1, e = 0.06, e = 0.04, etc. show typical slip rates), and the slip rates can be controlled to be appropriate values that always correspond to the operating state of the engine.

In the lockup region C where the vehicle speed is V ₂ or higher in FIG. 7, the spool 30b is also moved to the lower half position in the diagram by the governor pressure P _G as described above. Therefore, the lockup control pressure P _{L / u} in the chamber 18
Is removed from the drain port 30d through the hollow hole 11a and the circuit 34 and becomes zero, so that the lockup clutch 16 is completely joined to the converter cover 5 by the converter pressure P _C in the chamber 17. In this case, the engine power is transmitted to the torque converter output shaft 11 via the converter cover 5, the lockup clutch 16 and the sleeve 11, and the torque converter can be operated in the lockup state where the slip rate e is 0.

Next, to explain the operation of the creep prevention device 101, when the vehicle is stopped with the manual valve 41 in the forward travel range and the line pressure P _L from the circuit 42 is supplied to the circuit 39, that is, in FIG. In the creep prevention region D in which the medium vehicle speed is equal to or less than the minute set value and the throttle opening is also equal to or less than the minute set value, the low governor pressure P _G and the slotter pressure P _TH corresponding to the vehicle speed and the throttle opening are the spool 36b and the spring 36.
Zupur 36b, which can be moved to the right against a, is kept in the upper half position in the figure. In this case, the circuit 38 leads to the circuit 33 and the forward clutch actuation hydraulic pressure P _{F / C} is brought to the torque pressure P _T. When the torque pressure P _T is too high and the torque converter output torque is larger than the limit value for preventing creep due to the excessive fastening force of the forward clutch 37, and the creep occurs, the variable orifice 19 will increase the torque converter output torque. The opening degree S is reduced by the above-mentioned effect by an excessive amount. As a result, the torque pressure P _T is reduced, the fastening force of the forward clutch 37 is reduced, and the output torque of the torque converter is reduced to prevent creep. Conversely, torque pressure
P _T is too low and the torque converter output torque is smaller than the above limit value due to insufficient fastening force of the forward clutch 37,
When creeping does not occur, but the forward clutch 37 at the time of starting causes a complete engagement delay, the variable orifice 19 has the opening S increased by the above-mentioned action by the shortage of the torque converter output torque. As a result, the torque pressure P _T rises, increasing the fastening force of the forward clutch 37,
The torque converter output torque is increased to the above limit value. As a result of repeating the above actions, the torque pressure P _T is controlled so that the torque converter output torque reaches the above-mentioned limit value, and the forward clutch 37 is kept in the semi-engaged state of the limit required for creep prevention to prevent creep. can do.

When the throttle opening is increased during start, the corresponding high throttle pressure P _TH causes the spool 36b to move to the lower half position in the figure. At this time, the line pressure P _{L of the} circuit 39 is supplied to the forward clutch 37 as the operating hydraulic pressure P _{F / C} , and the vehicle can be started by completely engaging the forward clutch 37. By the way, since this complete engagement is executed from the above-mentioned half-engaged state, it is completed promptly without any delay, no delay in starting is caused, and no engine is blown to cause a shock.

During normal driving thereafter, the vehicle speed is sufficiently high, and the corresponding high governor pressure P _G keeps the spool 36b in the lower half position in the figure, so the forward ward clutch 37 has a slot pressure P _TH.
When the engine brake is running, the hook is kept in the completely engaged state, and normal running is not hindered.

FIG. 3 shows another example of the torque pressure generating means for generating the torque pressure P _{T. In} this example, the turbine hub flange 9a is slidably fitted to the sleeve flange 10a, and the pressure chamber 44 is defined between them. To achieve. Ball grooves 45, 4 on the facing surfaces of the flanges 9a, 10a, respectively
6, which extend along an arc of radius R centered on the torque converter output shaft 11 and face each other. Further, although the bottom surfaces of the ball grooves 45, 46 are parallel to each other, the flange 9 as shown by 45a, 46a in FIG.
A cam mechanism that functions as will be described later is formed by inclining by θ with respect to the rotation surfaces of a and 10a and interposing one common ball 47 between these ball groove bottom surfaces 45a and 46a.

The converter chamber 17 communicates with a drain circuit 29 through a variable orifice 48 formed by an axial slit 9c formed in the turbine hub 9 and a hole 10f formed in the sleeve 10, a hole 10b formed in the sleeve 10 and a hole 11b in the shaft 11. Let The sleeve 10 is further provided with a hole 10g, which allows the pressure chamber 44 to communicate with the hole 10b. It is assumed that the variable orifice 48 is changed in opening degree shown by hatching in FIG. 5 according to the overlapping amount of the slit 9c and the hole 10f.

Also in this example, the converter pressure P _C in the converter chamber 17 is partially drained through the variable orifice 48, the holes 10b and 11b, the circuit 29 and the fixed orifice 28, and the variable orifice 48 and the fixed orifice 28 have a variable orifice 48 between them. The torque pressure P _T determined by the opening is generated and output to the circuit 23.

Here, considering the force acting on the turbine hub 9, since the frictional force between this and the ball 47 is negligible, if this is ignored, the generated torque T on the turbine hub 9 will be as shown in FIG. _The force F _T generated by _T and the force F _L generated by the pressure difference between the converter chamber pressure P _C and the torque pressure P _T reaching the pressure chamber 44 act on the pressure receiving area S _L of the turbine hub 9, and the ball 47
Has a drag force N and balances the resultant force of these forces. By the way, the above F _T and F _L are respectively expressed by F _T = T _{T / R} (1) F _L = (P _C −P _T ) × S _L (2), and in the above-mentioned balanced state, F _T , F _L is F _T ＝ N sin respectively
theta, since represented even F _L = N cosθ, relational expression _{F L tanθ = F T ... (} 3) is obtained.

Solving the simultaneous equations (1) and (3), And solve the system of equations (2) and Is required. In this equation (4), P _C and Is constant, and accordingly, the torque pressure P _T becomes the same as that in FIG. 6 in which the torque pressure P _T decreases as the torque converter output torque T _T increases, and the torque pressure P _T is controlled by the slip control in the same manner as in the above-described example also in the configuration of this example. It can be used as a control factor for the device 100 and the creep prevention device 101.

(Effects of the Invention) Thus, as described above, the combined control device of the present invention determines the torque pressure P _T corresponding to the torque converter output torque in the slip control device 100 and the creep prevention device 101 in which the torque converter output torque is one of the control factors. Since it is configured such that only one means is generated in common, an automatic transmission equipped with both a slip control device and a creep prevention device and a 雖 also share many parts of both of these devices so that the automatic transmission The number of parts of the machine can be reduced, the hydraulic circuit can be simplified, and the cost of the automatic transmission can be reduced.

According to the configuration of the present invention, as a result, the means for generating the torque pressure P _T is separated from the lockup control chamber 18 in terms of the circuit, and when the lockup clutch 16 is completely connected, the residual pressure in the lockup control chamber 18 is reduced. And the additional advantage of preventing a decrease in the lock-up capacity can be obtained.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of a combined control device of the present invention, FIG. 2 is a view taken along the arrow II in FIG. 1, and FIG. 3 is a sectional view of a torque converter showing another example of the torque pressure generating means. 4 is a developed sectional view taken along the line IV-IV in FIG. 3, FIG. 5 is a view taken in the direction of arrow V in FIG. 3, and FIG. 6 is a torque pressure control characteristic diagram of the torque pressure generating means used in the present invention. FIG. 7 is a diagram showing the slip control characteristics and the creep prevention region obtained by the apparatus of FIG. 1 ... Torque converter, 2 ... Pump impeller 3 ... Turbine runner, 4 ... Stator 5 ... Converter cover, 9 ... Turbine hub 10 ... Sleeve 11 ... Torque converter output shaft 14 ... Outer spring, 15 ... Inner spring 16 ... Rock up clutch 17 … Converter room, 18… Lockup control room 19,28… Torque pressure generating means (19… Variable orifice, 28…
29. 1st slip control valve 30 ... 2nd slip control valve 36 ... Creep prevention valve 37 ... Forward clutch 41 ... Manual valve, 44 ... Pressure chamber 45,46 ... Ball groove, 47 ... Ball 48, 28 ... Torque pressure generating means (48 ... variable orifice, 28 ...
Fixed orifice) P _C … Converter pressure, P _T … Torque pressure P _L … Line pressure P _{L / u} … Lockup control pressure P _G … Governor pressure, P _TH … Slottle pressure 100,101… Multiple control devices (100… Slip control device) ,Ten
1… Creep prevention device)

Claims (1)

[Claims] 1. An automatic transmission having a torque converter whose slip is controlled by adjusting the pressure of a lock-up control chamber in a transmission system, wherein a starting friction element is fluidly fastened to enable output of rotation from the torque converter. In a torque control device for generating a torque pressure corresponding to the output torque of the torque converter, and a slip control device for supplying the torque pressure to the lock-up control chamber to cause a slip control of the torque converter. And a creep prevention device that causes the creep prevention action of the torque converter to occur by supplying the torque pressure to the starting friction element instead of the fluid pressure, and a composite control device for an automatic transmission.