JP2008045653A - Hydraulic control device for automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydraulic control device for an automatic transmission having compatibility between both of the avoidance of speed change feeling deterioration such as the racing of an engine or torque shocks, and the prompt changing of speed stages. <P>SOLUTION: An input side hydraulic switch 23 is provided for detecting that the clutch oil pressure of an input side friction element C3 has reached first predetermined oil pressure when carrying out the change-over control of the engagement with the input side friction element C3 and the release of a relaxing side friction element C2 at the same time, and a relaxing side hydraulic switch 23 is provided for detecting that the clutch oil pressure of the relaxing side friction element C2 has reached second predetermined oil pressure. In a speed change ECU 7, duration the starting of the change-over control until engagement and duration until release are calculated on the basis of the detection of the hydraulic switches 23, and command signals with respect to the input side friction element C3 and the relaxing side friction element C2 are corrected on the basis of the duration until engagement and duration until release. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a hydraulic control device for an automatic transmission that switches a gear position of the automatic transmission.

  Conventionally, an automatic transmission for an automatic transmission that switches the gear stage of an automatic transmission by controlling the engagement or release of the friction element by controlling the clutch hydraulic pressure that operates a plurality of friction elements provided in the automatic transmission. A hydraulic control device is known (see Patent Document 1). This type of hydraulic control device is provided with a control valve for controlling the clutch hydraulic pressure of the friction element for each friction element, and each control valve is activated by outputting a command signal to each control valve from the electronic control device. Thus, the clutch hydraulic pressure of the friction element is controlled, and as a result, the engagement speed or the release speed of each friction element is controlled. Then, the gear position is determined by a combination of engagement and release of each friction element. Therefore, the gear position is switched by changing the combination of the engagement and release.

  Here, in recent years, in order to quickly change the gear position, change control that simultaneously executes the engagement and release has been performed. In order to simultaneously perform engagement and disengagement in this way, the clutch hydraulic pressure of the first friction element is raised to change from the released state to the engaged state, and at the same time the clutch hydraulic pressure of the second friction element is lowered to engage. The combined state may be changed to the released state. However, in such exchange control, the torque shock and engine blow-up described below occur only when the engagement and release timing are slightly shifted from the ideal timing.

  That is, if the engagement timing is too fast or the release timing is too late, the actual clutch capacity momentarily overshoots the appropriate clutch capacity of the automatic transmission, and a sharp shock (so-called so-called) (Torque shock) occurs, which is an unpleasant shock for the vehicle occupant as if the brakes were applied. On the other hand, if the engagement timing is too late or the release timing is too fast, the actual clutch capacity becomes extremely small with respect to the appropriate clutch capacity of the automatic transmission, and the engine blows up.

  In order to solve such problems in the transfer control, conventionally, a fluctuation in the engine speed is detected, and a command signal is corrected based on the detected value, thereby increasing the clutch hydraulic pressure increase speed of the first friction element. Thus, the timing of engagement and disengagement is corrected so as to approach the ideal timing. A specific example of this correction will be described below with reference to FIG.

  In the example shown in FIG. 6, switching control when shifting up from the first gear to the second gear is shown, and the dotted line in the figure shows the change in the clutch hydraulic pressure of the first friction element. A solid line in the middle indicates a change in clutch hydraulic pressure of the second friction element. When the engagement and disengagement timings are ideal, the engine speed changes as indicated by the solid line in the figure. On the other hand, when the engine blow-up occurs, the engine speed changes as indicated by a dotted line R1 in the figure. When the torque shock occurs, the engine speed changes as indicated by a dotted line R2 in the figure. Become.

Therefore, in the conventional change control, the required time T0 from the start of the change control to the start point of decrease in the engine speed (start point of the inertia phase) in the case of ideal timing is stored in advance, and the required time If it is detected that a change in the engine speed indicated by the dotted line R1 has started before T0 has elapsed, the engine speed indicated by the dotted line R2 is corrected so as to increase the engagement speed of the first friction element. When it is detected that a change has started to occur, correction is made so as to slow down the engagement speed of the first friction element.
Incidentally, reference numerals t1 and t2 in FIG. 6 respectively indicate the timing when the first friction element starts engagement and the timing when the second friction element starts releasing.

JP 2005-36875 A

  However, as described above, it is possible to determine whether or not the timing of engagement and disengagement is deviated from the ideal timing by simply detecting the fluctuation of the engine speed, but due to the deviation of the engagement timing of the first friction element. It cannot be determined whether this is due to the difference in the release timing of the second friction element or the cause. Therefore, in the conventional switching control, as described above, only the rising speed of the clutch hydraulic pressure of the first friction element is corrected based on the fluctuation of the engine speed, and the lowering speed of the clutch hydraulic pressure of the second friction element is corrected. It has not been done.

  Then, for example, when the engine speed change indicated by the dotted line R2 starts to occur due to the release timing being too late, the engagement speed of the first friction element is reduced rather than correction that increases the release timing. As a result, the engagement timing is corrected so as to be delayed, so that the shift of the gear position is extremely delayed, and the shift of the gear position is delayed.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an automatic transmission hydraulic control device that achieves both the avoidance of deterioration of the shift feeling such as engine blow-up and torque shock and the rapid switching of the shift stage. is there.

According to the first aspect of the present invention, the first detection means for detecting the time from the start of the switching control until the clutch hydraulic pressure of the first friction element reaches the first predetermined hydraulic pressure, and the switching control is started. And a second detecting means for detecting a time until the clutch hydraulic pressure of the second friction element reaches the second predetermined hydraulic pressure. Therefore, it is possible to detect both the engagement timing of the first friction element and the release timing of the second friction element. Then, the first command signal is corrected based on the detection time by the first detection means, and the second command signal is corrected based on the detection time by the second detection means. Both timings with the release timing of the second friction element can be corrected appropriately.

More specifically, for example, when the detection time by the first detection means is longer than the ideal time, the first command signal is corrected so as to increase the rate of increase of the clutch hydraulic pressure to the first friction element, and the first When the detection time by the detection means is shorter than the ideal time, the first command signal can be corrected so as to reduce the rising speed of the clutch hydraulic pressure to the first friction element. When the detection time by the second detection means is longer than the ideal time, the second command signal is corrected so as to increase the lowering speed of the clutch hydraulic pressure to the second friction element, and the detection time by the second detection means is ideal. When the time is shorter than the time, the second command signal can be corrected so as to reduce the rising speed of the clutch hydraulic pressure to the second friction element.
As described above, according to the first aspect of the present invention, it is possible to achieve both avoidance of deterioration of the shift feeling such as engine blow-up and torque shock and rapid switching of the shift stage.

According to a second aspect of the present invention, it is preferable that the time from when the clutch control of the friction element reaches the predetermined hydraulic pressure is detected by detecting the clutch hydraulic pressure. .
In addition, when the first and second hydraulic pressure detection devices detect that the clutch hydraulic pressure of the friction element has reached a predetermined hydraulic pressure, a detection signal including information to that effect is output to the electronic control device. It is preferable to employ a hydraulic switch that does this.

Here, the change in the clutch hydraulic pressure of the friction element with respect to the change in the command signal output from the electronic control device changes depending on the temperature of the hydraulic oil. For example, when the temperature of the hydraulic oil is low, the response of the change in the clutch oil pressure to the change in the command signal is deteriorated.
On the other hand, in the invention according to claim 4, since the electronic control device corrects the correction amounts of the first and second command signals in accordance with the temperature of the hydraulic oil that operates the plurality of friction elements, the electronic control device Can correct the command signal with high accuracy according to the temperature change.

  According to the fifth aspect of the present invention, the map indicating the relationship between the detection time by the first and second detection means and the correction amount is provided for each temperature of the hydraulic oil, and the correction amount is determined according to the temperature of the hydraulic oil. When the map of the corresponding temperature is corrected to correct, the maps for other temperatures are also corrected in the same manner. Therefore, for example, when the temperature of the hydraulic oil rises with time since the start of operation of the vehicle engine, the map for low temperature is corrected and the map for high temperature is also corrected before the temperature rises. Rapid map correction can be done.

  According to the sixth aspect of the present invention, the change control is forcibly performed during the idling operation immediately after the engine is started, and the first and second command signals are corrected by the electronic control device prior to the traveling operation after the idling operation. I do. Therefore, it is possible to correct the command signal quickly.

  Here, there is some variation in the magnitude of the clutch hydraulic pressure when the first friction element starts to be engaged during the switching control. On the other hand, in the invention according to claim 7, the first predetermined hydraulic pressure is set to a pressure higher than the clutch hydraulic pressure when the first friction element starts to be engaged during the switching control. Thus, the time from the start of the switching control to the engagement of the first friction element can be reliably detected.

  Similarly, there is some variation in the magnitude of the clutch hydraulic pressure when the second friction element starts to be released during the switching control. On the other hand, in the invention according to claim 8, the second predetermined hydraulic pressure is set to a pressure higher than the clutch hydraulic pressure when the second friction element starts to be released during the switching control. The time until the second friction element is released after the change control is started can be reliably detected.

Hereinafter, each embodiment of the present invention will be described with reference to FIGS.
(First embodiment)
Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. In the following description, “automatic transmission” is abbreviated as “AT”.
(First embodiment)
FIG. 2 shows an AT and an AT hydraulic control apparatus according to the first embodiment of the present invention. The AT 1 and the AT hydraulic control device 2 shown in FIG. 2 are mounted on a vehicle provided with a traveling engine 3.
As shown in FIG. 2, the rotational torque of the engine 3 is input to the AT 1 through the torque converter 4, and the AT 1 controls the rotational speed of the output shaft 6 with respect to the rotational speed of the input shaft 5. . The AT hydraulic control device 2 controls hydraulic fluid supplied to the AT 1 based on a control command of the transmission ECU 7 and is attached to a lower portion of the AT 1. The shift ECU 7 corresponds to an “electronic control device” recited in the claims.

Next, the structure of AT1 will be described with reference to FIG.
The AT 1 has a plurality of friction elements 11. Since all the friction elements have the same structure, only one friction element 11 is shown in FIG. The number of friction elements according to the present embodiment is six. Hereinafter, in addition to the friction element being denoted by reference numeral 11, three friction elements that function as brakes are denoted by B1, B2, and B3 and function as clutches. The three friction elements are represented as C1, C2, and C3 (see FIG. 3). Then, the friction elements B1 to B3 and C1 to C3 are brought into an engaged state or a released state according to the hydraulic pressure of the hydraulic oil applied by the AT hydraulic control device 2.

As shown in FIG. 1, each of the friction elements 11 includes a plurality of output friction plates 11a, a plurality of input friction plates 11b, and a drive unit including a clutch piston 11c and a piston chamber 11d.
Hydraulic fluid is supplied to the piston chamber 11d from the AT hydraulic control device 2, and the clutch piston 11c strokes in the axial direction in accordance with the supplied hydraulic pressure (hereinafter referred to as "applied hydraulic pressure"). The coil spring 11e biases the clutch piston 11c away from the input friction plate 11b. When the hydraulic pressure applied to the clutch piston 11c is low, the coil spring 11e is not shown between the clutch piston 11c and the corresponding input friction plate 11b. As shown in FIG. At this time, the input friction plate 11b and the output friction plate 11a are separated from each other, so that the torque transmission from the input shafts 5 and 11g to the output shafts 6 and 11f is released.

When the hydraulic pressure applied to the clutch piston 11c increases, the clutch piston 11c starts a stroke toward the input friction plate 11b. When the clutch piston 11c makes a stroke, the clutch piston 11c comes into contact with the nearest input friction plate 11b and is temporarily locked by the input friction plate 11b.
When the applied hydraulic pressure to the clutch piston 11c locked to the input friction plate 11b further increases, the clutch piston 11c pushes and moves the input friction plate 11b to resume the stroke. As a result, the input friction plate 11b and the output friction plate 11a are brought into frictional contact, and torque is transmitted from the input shafts 5 and 11g to the output shafts 6 and 11f.

  FIG. 3 is a schematic diagram showing the relationship between the shift speed of AT1 and the friction elements 11 (B1 to B3, C1 to C3). AT1 is provided with a parking range (P range), a neutral range (N range), a forward range (D range), and a reverse range (R range) as shift ranges, and five shift stages in the D range are prepared. ing.

  Here, “◯” shown in FIG. 3 indicates a friction element that is engaged when the corresponding gear stage is realized. The gear position in the D range is switched by changing the combination of engagement and release of the friction elements B1, B3, C1 to C3 as shown in the figure. In the parking range and the neutral range, the friction elements B1 and C2 may be engaged as described later or may be released.

Next, the AT hydraulic control device 2 will be described.
The AT hydraulic control device 2 includes a clutch control valve 21, a solenoid valve 22, a hydraulic switch 23, a transmission ECU 7, and the like as first and second control valves. The clutch control valve 21, the solenoid valve 22, and the hydraulic switch 23 are provided. Is provided for each of the friction elements 11 (B1 to B3, C1 to C3). These mechanical elements 21, 22, and 23 are unitized by being accommodated in one casing, and are attached to the AT 1 as one unit.

  As shown in FIG. 1, the clutch control valve 21 includes a spool 211 and a housing 212 that accommodates the spool 211 so as to be reciprocally movable in the axial direction. The spool 211 is provided with a plurality of lands, and the outer peripheral wall of the land slides with the inner peripheral wall of the housing 212. A plurality of ports are opened in the housing 212, and a passage through which hydraulic oil flows is connected to each port. The clutch control valve 21 has a spring 213 as an urging means at one end of the spool 211 in the axial direction. Further, the clutch control valve 21 has a modulated pressure input portion 214 to which hydraulic oil is supplied to the end portion of the spool 211 on the side opposite to the spring.

  The transmission ECU 7 outputs a command signal to the solenoid valve 22 based on the detection signal from the hydraulic switch 23. The solenoid valve 22 controls the supply amount of the hydraulic oil having a modulated pressure to the modulated pressure input unit 214 based on the command signal. The spool 211 of the clutch control valve 21 stops at a position where the force received from the hydraulic oil having the modulated pressure introduced into the modulated pressure input portion 214 and the force received from the spring 213 are balanced. Since the pressing force of the spring 213 is substantially constant, the axial position of the spool 211 is changed by adjusting the modulation pressure introduced into the clutch control valve 21 at the modulation pressure input portion 214.

  As a result, the connection state of each port of the housing 212 changes, the connection passage portion 24 through which the hydraulic oil of the line pressure supplied to the clutch control valve 21 flows, and the control passage portion 25 from which the hydraulic oil is discharged from the clutch control valve 21. The connection state with is changed. The clutch control valve 21 is connected to the friction element 11 via the control passage portion 25 and adjusts the clutch hydraulic pressure in the piston chamber 11d. As a result, switching between engagement and release of the friction element 11 is executed based on a command signal from the transmission ECU 7.

In the example shown in FIG. 1, when the modulated pressure oil is discharged from the modulated pressure input portion 214 and the spool 211 moves to the left side of FIG. 1, the supply of the line pressure hydraulic oil to the piston chamber 11d is shut off. Then, the hydraulic oil in the piston chamber 11d is discharged, and the clutch hydraulic pressure of the friction element 11 decreases. On the other hand, when the modulating pressure oil is supplied to the modulating pressure input unit 214 and the spool 211 moves to the right side in FIG. 1, the line pressure hydraulic oil is supplied to the piston chamber 11d. Then, the clutch hydraulic pressure of the friction element 11 increases.
Incidentally, the modulating pressure and the line pressure are generated by the generating means (not shown) from the oil discharged from the oil pump 8 (see FIG. 2) that is rotationally driven together with the input shaft 5.

  The hydraulic switches 23 communicate with the corresponding control passage portions 25 and are electrically connected to the common speed change ECU 7. The hydraulic switch 23 detects the hydraulic pressure output from the clutch control valve 21 on the upstream side of the corresponding control passage portion 25 and applied to the friction element 11 on the downstream side. That is, the clutch hydraulic pressure is detected. When the hydraulic switch 23 detects that the clutch hydraulic pressure has reached a predetermined hydraulic pressure set in advance, the hydraulic switch 23 outputs a detection signal including information to that effect to the transmission ECU 7. These hydraulic switches 23 correspond to the hydraulic pressure detection device described in the claims.

  The throttle valve 26 shown in FIG. 1 is for reducing the pulsation of the line pressure supplied to the friction element 11, and the hydraulic switch 23 is disposed on the friction element 11 side of the throttle valve 26. Yes. As a result, the hydraulic switch 23 is operated based on a pressure closer to the clutch hydraulic pressure that is actually applied, and the hydraulic pressure in which the pulsation is suppressed by the action of the throttle valve 26 can be detected, so that the detection accuracy is increased.

Next, the operation when shifting up the first gear to the second gear will be described.
As shown in FIG. 3, the shift-up is performed by increasing the clutch hydraulic pressure of the friction element C3 (hereinafter referred to as the entry-side friction element C3) to change the engagement state from the released state to the friction element C2 (hereinafter referred to as the removal side). This is performed by changing the clutch hydraulic pressure of the friction element C3) to lower the clutch oil pressure from the engaged state to the released state.
The transmission ECU 7 is mainly composed of a microcomputer. The shift ECU 7 generates and outputs a command signal to the solenoid valve 22 based on the vehicle-related information by executing a control program stored in the memory by the CPU.

  That is, in the switching control in this case, the command signal (first command signal described in the claims) output from the shift ECU 7 output to the solenoid valve 22 corresponding to the input side friction element C3 is the input side friction. This is a signal for instructing the clutch control valve 21 corresponding to the element C3 to supply the modulated pressure oil. In addition, a command signal (second command signal described in claims) output from the shift ECU 7 output to the solenoid valve 22 corresponding to the extraction side friction element C2 is a clutch control valve 21 corresponding to the extraction side friction element C3. This is a signal for instructing the supply of the modulated pressure oil to stop.

  FIG. 4 is a graph showing the timing of the engagement of the input side friction element C3 and the release of the extraction side friction element C2 during the execution of the switching control. A dotted line in the figure indicates a change in clutch hydraulic pressure detected by the insertion side hydraulic switch 23 corresponding to the insertion side friction element C3, and a solid line in the figure indicates the extraction side corresponding to the extraction side friction element C2. A change in clutch hydraulic pressure detected by the hydraulic switch 23 is shown. In addition, the reference symbol P1 in the figure indicates the value of the predetermined hydraulic pressure set in the inlet side hydraulic switch 23, and the reference symbol P2 in the figure indicates the value of the predetermined hydraulic pressure set in the outlet side hydraulic switch 23. Yes.

  Therefore, when the clutch hydraulic pressure of the input side frictional element C3 rises to the predetermined oil pressure P1 after the change control is started, the input side hydraulic switch 23 outputs a detection signal including information to that effect to the speed change ECU 7. When the clutch hydraulic pressure of the side friction element C2 drops to the predetermined hydraulic pressure P2, the extraction side hydraulic switch 23 outputs a detection signal including information to that effect to the transmission ECU 7.

When the detection signal from the input side hydraulic switch 23 is input, the transmission ECU 7 calculates a required time T1 from the start of change control until the detection signal is input. Further, when the detection signal from the removal side hydraulic switch 23 is input, a required time T2 from the start of the switching control to the input of the detection signal is calculated. Note that the shift ECU 7 when executing this calculation corresponds to the detecting means described in the claims.
Therefore, the required time T1 corresponds to the time from the start of the change control until the insertion side friction element C3 is engaged, and the required time T2 is the time from the start of the change control to the release side friction element C2 being released. Equivalent to.

  Then, the transmission ECU 7 corrects the first command signal on the input side based on the calculated required time T1, and corrects the second command signal on the extraction side based on the calculated required time T2. As a result, it is possible to appropriately correct both the engagement timing of the insertion side friction element C3 and the release timing of the extraction side friction element C2.

The details of the correction by the speed change ECU 7 will be described more specifically. For example, when the required time T1 on the input side is longer than the ideal time, the first command is set so as to increase the rate of increase of the clutch hydraulic pressure to the input side friction element C3. When the required time T1 on the input side is shorter than the ideal time, the first command signal is corrected so as to reduce the rate of increase of the clutch hydraulic pressure to the input side friction element C3.
When the required time T2 on the withdrawal side is longer than the ideal time, the second command signal is corrected so as to increase the lowering speed of the clutch hydraulic pressure to the withdrawal friction element C2, and the required time T2 on the removal side is the ideal time. If it is shorter, the second command signal is corrected so as to reduce the rate of increase of the clutch hydraulic pressure to the extraction side friction element C2.

  As described above, according to the first embodiment, both the required time T1 on the insertion side and the required time T2 on the removal side are detected. Therefore, the clutch hydraulic pressure to the insertion side friction element C3 and the clutch to the removal side friction element C2 are detected. Both the oil pressure and the oil pressure can be corrected by feedback control. Therefore, both the engagement timing of the entry side friction element C3 and the release timing of the removal side friction element C2 can be corrected appropriately, and avoiding deterioration of the shifting feeling such as engine blow-up and torque shock, It is possible to achieve both the speed change of gears quickly.

Note that reference numerals t1 and t2 in FIG. 4 indicate the timing at which the insertion-side friction element C3 starts to engage and the timing at which the removal-side friction element C2 starts to release, respectively. The predetermined hydraulic pressure P1 set in the input side hydraulic switch 23 is set to a value larger than the clutch hydraulic pressure when the input side friction element C3 starts to be engaged, and the predetermined hydraulic pressure set in the extraction side hydraulic switch 23 is set. P2 is set to a value larger than the clutch hydraulic pressure when the extraction side friction element C2 starts to be engaged.
Therefore, it is possible to absorb the variation in the clutch hydraulic pressure when the friction element 11 starts to be engaged or released during the change control, and from the start of the change control until the friction element 11 is engaged or released. Time T1 and T2 can be detected reliably

(Second Embodiment)
In the second embodiment, the transmission ECU 7 corrects the correction amount of the command signal output to the solenoid valve 22 according to the hydraulic oil temperature of the line pressure. This will be described more specifically with reference to FIG. A dotted line in FIG. 5 indicates a change in the command value output from the speed change ECU 7 to the input side solenoid valve 22 when the changeover control is executed. A solid line in FIG. 5 shows a map for predicting a change in the clutch hydraulic pressure of the closing friction element C3 with respect to a change in the command signal.

Here, the change in the clutch hydraulic pressure of the friction element 11 with respect to the change in the command signal output from the transmission ECU 7 changes depending on the temperature of the hydraulic oil. For example, when the temperature of the hydraulic oil is low, the response of the change in the clutch hydraulic pressure to the change in the command signal is deteriorated due to the increase in the viscosity of the hydraulic oil. Therefore, in the second embodiment, the map is provided for each hydraulic oil temperature. FIG. 5A is a map at a low temperature, and FIG. 5B is a map at a high temperature.
Based on these maps, the shift ECU 7 outputs a command value so as to achieve a desired clutch oil pressure and corrects the command signal based on the required times T1 and T2.

When a follow-up delay occurs in the clutch hydraulic pressure increase with respect to the command value increase as shown in FIG. 5A, the map command value is corrected as shown by the solid line in FIG. 5C. And when the command value of a map is corrected in this way, the maps for other temperatures are similarly corrected. In the example shown in FIG. 5, the map of the high temperature region is also corrected as shown by the solid line in FIG. 5 (d) as the map of the low temperature region is corrected as shown by the solid line in FIG. 5 (c).
Therefore, for example, when the temperature of the hydraulic oil rises with time since the start of operation of the vehicle engine, the map for the low temperature range is corrected and the map for the high temperature range is also corrected before the temperature rises. Therefore, quick map correction can be performed.

(Third embodiment)
In the third embodiment, the shift ECU 7 forcibly executes the change control for the friction element 11 that is unrelated to the shift at the time of idling immediately after the engine is started, and the map shown in FIG. The map is corrected in light of the change in clutch hydraulic pressure detected by.

  More specifically, as shown in FIG. 3, when idling, the shift range is the P range or the N range. In this case, the two friction elements B1 and C2 are friction elements 11 that are unrelated to the shift. Yes, unless the other friction elements C1, C3, B2, and B3 are engaged, the vehicle will not travel even if the friction elements B1 and C2 are engaged and released. Then, the switching control is forcibly executed at the idling time for these friction elements B1 and C2, and the command signal is compared with the change in the clutch hydraulic pressure detected by the hydraulic switch 23 at that time and the map shown in FIG. The map is corrected to reflect the correction thereafter. According to this, it is possible to quickly correct the command signal.

(Other embodiments)
In each of the above embodiments, a pilot valve that operates the spool 211 with a modulated pressure is employed, and the first and second control valves described in the claims are configured by a clutch control valve 21 having a solenoid valve 22. However, in carrying out the present invention, an electromagnetic valve that operates the spool 211 by electromagnetic force generated by energizing the coil may be employed as the first and second control valves. In this case, energization to the coil is switched by a command signal from the speed change ECU 7.
As described above, the present invention is not limited to the above-described embodiment, and can be applied to various embodiments without departing from the gist thereof.

1 is a schematic diagram showing an AT and an AT hydraulic control device according to a first embodiment of the present invention. It is a schematic diagram which shows the vehicle mounting position of the hydraulic control apparatus for AT shown in FIG. In 1st Embodiment, it is explanatory drawing which shows the combination of the engagement state of the friction element in each gear stage. 7 shows a map for predicting a relationship between a change in a command value output from a speed change ECU and a change in clutch hydraulic pressure of an input side friction element with respect to the change during execution of a changeover control according to the first embodiment. FIG. 6 is a map for predicting a relationship between a change in command value and a change in clutch hydraulic pressure with respect to the change in change control according to the second embodiment of the present invention; a map for a low temperature region and a map for a high temperature region Indicates the contents to be corrected. It is a graph which shows the relationship between an engine speed and the change of the clutch hydraulic pressure of a friction element regarding the conventional transfer control.

Explanation of symbols

  1: AT (automatic transmission), 2: AT hydraulic control device, 7: Shift ECU (electronic control device), C2: Pull-off friction element (second friction element), C3: Insertion-side friction element (first friction) Element), 21: clutch control valve (first control valve, second control valve), 22: solenoid valve (first control valve, second control valve), 23: hydraulic switch (first and second detection means).

Claims (8)

The hydraulic pressure for an automatic transmission that controls the clutch hydraulic pressure for operating a plurality of friction elements provided in the automatic transmission to control the engagement or release of the friction elements to switch the shift stage of the automatic transmission. In the control device,
A first control valve that controls a clutch hydraulic pressure of a first friction element that is one of the plurality of friction elements;
A second control valve that controls a clutch hydraulic pressure of a second friction element that is one of the plurality of friction elements;
An electronic control unit that outputs a first command signal that commands the operation of the first control valve, and a second command signal that commands the operation of the second control valve;
When the clutch hydraulic pressure of the first friction element is increased to change from the released state to the engaged state, and at the same time, the clutch hydraulic pressure of the second friction element is decreased to change from the engaged state to the released state. First detection means for detecting a time from when the changeover control is started until the clutch hydraulic pressure of the first friction element reaches a first predetermined hydraulic pressure;
Second detection means for detecting a time from when the change control is started until the clutch hydraulic pressure of the second friction element reaches a second predetermined hydraulic pressure;
With
The electronic control unit corrects the first command signal based on the detection time by the first detection means and corrects the second command signal based on the detection time by the second detection means. Hydraulic control device. The first detection means includes a first hydraulic pressure detection device that detects a clutch hydraulic pressure of the first friction element;
2. The hydraulic control device for an automatic transmission according to claim 1, wherein the second detection unit includes a second hydraulic pressure detection device that detects a clutch hydraulic pressure of the second friction element. The first hydraulic pressure detection device is a hydraulic switch that outputs a first detection signal including information to the electronic control device when detecting that the clutch hydraulic pressure of the first friction element has reached the first predetermined hydraulic pressure. Yes,
The second hydraulic pressure detection device is a hydraulic switch that outputs to the electronic control device a second detection signal including information indicating that the clutch hydraulic pressure of the second friction element has reached the second predetermined hydraulic pressure. The hydraulic control device for an automatic transmission according to claim 2.   The automatic transmission according to any one of claims 1 to 3, wherein the electronic control device corrects the correction amounts of the first and second command signals according to the temperature of hydraulic oil that operates the plurality of friction elements. Hydraulic control device for machine.   The electronic control device has a map showing the relationship between the detection time by the first and second detection means and the correction amount for each temperature of the hydraulic oil, and the correction amount according to the temperature of the hydraulic oil. 5. The hydraulic control device for an automatic transmission according to claim 4, wherein when the map of the corresponding temperature is corrected so as to correct, the maps for other temperatures are also corrected in the same manner. The first and second friction elements are friction elements that do not become a shift stage in which the vehicle can travel only by engagement of these friction elements,
2. The first and second command signals are corrected by the electronic control unit prior to the traveling operation after the idling operation by forcibly performing the switching control during the idling operation immediately after the engine is started. The hydraulic control device for an automatic transmission according to claim 5.   The automatic operation according to any one of claims 1 to 6, wherein the first predetermined hydraulic pressure is set to a pressure higher than a clutch hydraulic pressure when the first friction element starts to be engaged during the switching control. Hydraulic control device for transmission. The automatic transmission according to any one of claims 1 to 7, wherein the second predetermined hydraulic pressure is set to a pressure higher than a clutch hydraulic pressure when the second friction element starts to be released during the switching control. Hydraulic control device for machine.

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