control device

Abstract

To provide a control apparatus capable of suppressing generation of an abnormal noise or shock by a clutch with respect to shifting operation of a transmission in a high engine output state.SOLUTION: A control apparatus 1 performing engagement control of a clutch 41 has an output determination part 62 which directly or indirectly determines output of an engine 3. When a shift range of a transmission 20 is switched from a non-traveling range to a traveling range, the control apparatus performs the engagement control of the clutch 41 by passing through: a first engagement step S1 for using an engagement degree of the clutch 41 as a standby engagement degree lower than an engagement degree that enables power transmission under a condition of determining that the output of the engine 3 is predetermined output or more; and a second engagement step S2 for improving the engagement degree of the clutch 41 so as to enable power transmission in the clutch 41 under the condition that rotational power inputted to the clutch 41 may be lower than a predetermined reference value. This suppresses the engagement of the clutch 41 in a high engine output state.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a control device for controlling clutch engagement.

Background Art

[0002] Conventionally, an automatic transmission in a vehicle controls the engagement and release of a clutch, for example, by operating a shift lever (shift range) to switch the driving state of the vehicle. By the way, in the control of the above-described automatic transmission, shift shock may occur depending on the timing of operating the shift lever (shift change). Therefore, for example, a technique related to a control method for an automatic transmission for a vehicle that suppresses shift shock that occurs when shifting from a driving range (also referred to as a D range or an R range) to a neutral (N range) and then switching back to the driving range again is disclosed (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the vehicle described above, in a state where the engine output (for example, engine speed) is high (also referred to as a racing garage), the driver may perform a shift operation from a non-driving range to a driving range. In such a case, since the clutch is engaged in a state where the difference between the rotational speed on the input side (engine side) of the clutch and the rotational speed on the output side (transmission side) of the clutch is large, there is a problem that clutch noise (abnormal noise) and engagement shock (also referred to as garage shock) occur during engagement. In addition, when the clutch is engaged in such a state, there is a problem that the clutch burns or wears, and the clutch deteriorates.

[0005] However, the control method described in Patent Document 1 solves the problems that arise when shifting from D range to N range and then back to D range, but it does not solve the gear shifting problems in the racing garage described above. Therefore, there is a need for a control device that can suppress clutch squeal and engagement shock during shifting operations in the racing garage described above.

[0006] Therefore, the present invention aims to provide a control device that can suppress the occurrence of abnormal clutch noise and shock during transmission shift operations when the engine output is high. [Means for solving the problem]

[0007] (1) The control device of the present invention, provided to solve the above-mentioned problems, is a control device that controls the engagement of a clutch provided in a transmission to which power generated in the engine of a vehicle is input, and has an output determination unit that directly or indirectly determines the output of the engine, and when the shift range of the transmission is switched from a non-driving range selected in a non-driving state to a driving range selected in a driving state, the first engagement step sets the engagement degree of the clutch to a standby engagement degree lower than the engagement degree that enables power transmission, on the condition that the output of the engine is determined to be above a predetermined output, and the second engagement step increases the engagement degree of the clutch so that it becomes capable of transmitting power, on the condition that the rotational power input to the clutch is below a predetermined reference value.

[0008] The control device described above performs a first engagement step in which, when the transmission's gear range is switched from a non-driving range to a driving range, the clutch engagement degree is set to a standby engagement degree lower than the engagement degree that enables power transmission, provided that the output determination unit determines that the engine output is above a predetermined output. Here, the condition for determining that the engine output is above a predetermined output is, for example, a state in which the engine output is increased due to accelerator operation (racing garage). Therefore, in the first engagement step, if the engine output is above a predetermined output (a state in which the engine output is increased), the clutch engagement degree is controlled to a standby engagement degree lower than the engagement degree that enables power transmission. As a result, the control device described above can suppress clutch squeal (abnormal noise) and clutch engagement shock (garage shock).

[0009] Furthermore, the control device described above, after the clutch engagement control by the first engagement step, performs a second engagement step control to improve the degree of clutch engagement so that the clutch becomes capable of power transmission, provided that the rotational power input to the clutch is lower than a predetermined reference value. Here, the predetermined reference value is set to, for example, the engine output at which no abnormal clutch noise occurs when the clutch is engaged, or the engine output at which no clutch engagement shock occurs. These engine outputs can be set based on data obtained in advance through experiments or output values ​​obtained from sensors, etc. Also, in the second engagement step, control is performed to improve the clutch engagement to a state where power transmission is possible, so abnormal clutch noise and engagement shock are suppressed.

[0010] (2) In the control device of the present invention described above, the standby engagement degree in the first engagement step is preferably the engagement degree in which the clutch is in contact.

[0011] The control device described above can rapidly transition the clutch engagement state (engagement degree) to an engagement degree where the clutch is in contact during the first engagement step. Here, the engagement degree at which the clutch is in contact is estimated to be, for example, the state just before power transmission becomes possible. Therefore, the control device described above can rapidly transition to the second engagement step that is executed thereafter, while suppressing the generation of abnormal clutch noise and clutch engagement shock, and safely engage the clutch (transmit power). The engagement degree at which the clutch is in contact can be determined experimentally in advance or obtained by installing a separate clutch pressure sensor and using the clutch pressure sensor.

[0012] (3) In the control device of the present invention as described above, the second engagement step may be started on the condition that it is determined that the second output is lower than or equal to the first output of the engine in the first engagement step.

[0013] By configuring the control device described above, it is possible to suppress the clutch from engaging in the high-power range of the engine. As a result, the control device can suppress the generation of abnormal clutch noise and engagement shock.

[0014] (4) In the control device of the present invention described above, the second engagement step is to be started on the condition that a predetermined time has elapsed since the clutch engagement control in the first engagement step was started.

[0015] The control device of the present invention, as described above, can suppress the initiation of clutch engagement in the high-output range of the engine. In other words, after a predetermined time has elapsed since the start of clutch engagement control, clutch engagement can be initiated when the engine output has decreased. As a result, the control device can suppress the generation of abnormal clutch noise and engagement shock.

[0016] (5) The control device of the present invention described above may have the output determination unit determine the output of the engine based on the rotational speed of the engine.

[0017] The control device described above, with this configuration, can perform highly accurate clutch engagement control based on the engine speed. Here, the engine speed can be obtained using an engine speed sensor or the like.

[0018] (6) In the control device of the present invention described above, the power generated in the engine is input to the transmission via a torque converter, and the output determination unit may indirectly determine the output of the engine based on the turbine rotation speed in the torque converter.

[0019] The control device described above, with this configuration, can perform highly accurate clutch engagement control based on the turbine rotation speed, which correlates with the engine output. The turbine rotation speed can be obtained, for example, by a turbine rotation sensor installed in a torque converter or the like.

[0020] (7) The control device of the present invention described above may reduce the output of the engine by suppressing the fuel supply to the engine in the first engagement step.

[0021] The control device described above, with this configuration, can smoothly reduce the engine output after the execution of the first engagement step. Therefore, the control device described above can quickly execute the control of the second engagement step, which is performed after the execution of the first engagement step. As a result, the control device described above can suppress the occurrence of time lag in gear shifting. [Effects of the Invention]

[0022] The present invention provides a control device that can suppress the occurrence of abnormal clutch noise and shock during transmission shift operations when the engine output is high. [Brief explanation of the drawing]

[0023] [Figure 1] This is a skeleton diagram of a vehicle equipped with a control device according to an embodiment of the present invention. [Figure 2] This is a block diagram showing the configuration of the control device of the present invention. [Figure 3] (a) and (b) are operation explanatory diagrams of a clutch used in the control device of the present invention. [Figure 4] (c) and (d) are operation explanatory diagrams of a clutch used in the control device of the present invention. [Figure 5] This is a timing chart showing the engagement control of a clutch by the control device of the present invention.

Embodiments for Carrying Out the Invention

[0024] Hereinafter, the control device 1 according to the embodiment of the present invention will be described with reference to FIGS. 1 to 5. Prior to the description of the control device 1, an overview of the vehicle 2 in which the control device 1 is provided will be described.

[0025] As shown in FIG. 1, in addition to the control device 1 (see FIG. 2), an engine 3 and a transmission unit 10 are provided in the vehicle 2. In the following description, in the input direction (power transmission direction) from the engine 3 serving as the power source, the front side (front) as viewed from the power source (engine) may be simply described as "front Fr" and the rear side (rear) as simply "rear Rr".

[0026] The engine 3 is provided with a throttle valve 4 (see FIG. 2) for adjusting the intake air amount into the combustion chamber of the engine 3, an injector (fuel injection device, not shown) for injecting fuel into the intake air, and a spark plug (not shown) for generating an electric discharge in the combustion chamber. Further, a starter (not shown) for starting the engine 3 is provided attached to the engine 3. The power of the engine 3 is transmitted to a differential gear (not shown) via the transmission unit 10, and is transmitted from the differential gear to the left and right drive wheels (not shown) via a drive shaft (not shown).

[0027] The transmission unit 10 is a unit that changes the power generated by the engine 3, which serves as the drive source for the vehicle. As shown in Figure 1, the transmission unit 10 is equipped with a torque converter 12, an input shaft 13, an output shaft 15, a continuously variable transmission 20 (CVT 20), a reverse transmission mechanism 30, a forward clutch 41 (clutch device 40), and a reverse clutch 49 (clutch device 40). The transmission unit 10 is also equipped with sensors such as a turbine rotation sensor 60 and an output shaft rotation sensor 61 (see Figure 2).

[0028] The torque converter 12 includes a pump impeller (not shown), a turbine runner (not shown), and a lock-up mechanism (lock-up clutch). The output shaft of the engine 3 (E / G output shaft) is connected to the pump impeller, and it is capable of rotating integrally with the E / G output shaft around the same rotation axis. The turbine runner is rotatable around the same rotation axis as the pump impeller. The lock-up mechanism is provided to directly connect / disconnect the pump impeller and the turbine runner. When the lock-up mechanism is engaged (lock-up on), the pump impeller and the turbine runner are directly connected, and when the lock-up mechanism is released (lock-up off), the pump impeller and the turbine runner are separated.

[0029] The input shaft 13 is positioned so that its axis coincides with the rotation axis of the torque converter. An input shaft gear 14 is integrally formed with the input shaft 13. The front end Fr of the input shaft 13 is inserted into the torque converter.

[0030] The output shaft 15 is positioned at a rearward Rr distance from the input shaft 13. The output shaft 15 is positioned so that its axis aligns with the axis of the input shaft 13. An output shaft gear 16 is integrally formed with the output shaft 15. The output shaft gear 16 meshes with a secondary output gear 25, which will be described later.

[0031] The continuously variable transmission 20 is provided with a primary shaft 21, a secondary shaft 23, a primary pulley 26, a secondary pulley 27, and a belt 28.

[0032] A primary input gear 22 is mounted on the primary shaft 21 so as to be rotatable relative to it. The primary input gear 22 meshes with the input shaft gear 14. A secondary input gear 24 and a secondary output gear 25 are mounted on the secondary shaft 23. The secondary input gear 24 is rotatable relative to the secondary shaft 23. The secondary output gear 25 is mounted so as not to be rotatable relative to the secondary shaft 23. The secondary output gear 25 meshes with the output shaft gear 16, which is located on the output shaft 15.

[0033] In the continuously variable transmission 20, a belt 28 is stretched between a primary pulley 26 and a secondary pulley 27. In the continuously variable transmission 20, the hydraulic pressure supplied to the hydraulic chambers (not shown) of the primary pulley 26 and the secondary pulley 27 is controlled, and the groove widths of the primary pulley 26 and the secondary pulley 27 are changed, thereby continuously changing the belt gear ratio (the pulley ratio between the primary pulley 26 and the secondary pulley 27) within a constant gear ratio range.

[0034] Furthermore, the continuously variable transmission 20 can be switched between a non-driving range, which is selected when the vehicle is not moving, and a driving range, which is selected when the vehicle is moving, by a gear lever (not shown) located in the driver's seat. Here, the non-driving range is a gear range selected when the vehicle 2 is not moving, such as the stop range (P range) or the neutral range (N range). The driving range is a gear range selected when the vehicle 2 is moving, such as the driving range (D range).

[0035] The reverse transmission mechanism 30 is a mechanism that transmits power (rotation) from the input shaft 13 to the secondary input gear 24. The reverse transmission mechanism 30 is provided with a reverse idler shaft 31, a first reverse gear 32, and a second reverse gear 33. The first reverse gear 32 is formed integrally with the reverse idler shaft 31 and meshes with the input shaft gear 14. The second reverse gear 33 is formed integrally with the reverse idler shaft 31 at the rear Rr of the first reverse gear 32 and meshes with the secondary input gear 24.

[0036] The forward clutch 41 (clutch device 40) is provided to allow / prevent the rotation of the primary input gear 22 relative to the primary shaft 21. As shown in Figures 3 and 4, the forward clutch 41 forms a clutch device 40 comprising a clutch drum 42, a clutch piston 43, friction material 44, a hydraulic chamber 45, a return spring 46, a cushioning material 47 (also referred to as an elastic member 47), etc. A hydraulic chamber 45 is formed between the clutch drum 42 and the clutch piston 43. The clutch piston 43 is elastically biased rearward Rr by the return spring 46. The supply of oil into the hydraulic chamber 45 can be controlled according to the output value of a solenoid (not shown).

[0037] As shown in Figure 1, when the forward clutch 41 is engaged (engaged state), relative rotation of the primary input gear 22 with respect to the primary shaft 21 is prohibited. In other words, the engagement of the forward clutch 41 causes the primary shaft 21 and the primary input gear 22 to rotate as a single unit. On the other hand, when the forward clutch 41 is released (released state), relative rotation of the primary input gear 22 with respect to the primary shaft 21 is permitted. Therefore, even if the primary input gear 22 rotates, that rotation is not transmitted to the primary shaft 21.

[0038] The reverse clutch 49 (clutch device 40) is provided to allow / prevent the rotation of the secondary input gear 24 relative to the secondary shaft 23. Since the reverse clutch 49 has the same configuration as the forward clutch 41, a detailed explanation is omitted.

[0039] When the reverse clutch 49 is engaged (engaged state), relative rotation of the secondary input gear 24 with respect to the secondary shaft 23 is prohibited. In other words, the engagement of the reverse clutch 49 causes the secondary shaft 23 and the secondary input gear 24 to rotate as a single unit. On the other hand, when the reverse clutch 49 is released (released state), relative rotation of the secondary input gear 24 with respect to the secondary shaft 23 is permitted. Therefore, even if the secondary input gear 24 rotates, that rotation is not transmitted to the secondary shaft 23.

[0040] In the following explanation, the forward clutch 41 and the reverse clutch 49 may be collectively referred to simply as "clutch device 40".

[0041] Furthermore, the amount of oil supplied to the hydraulic chamber 45 of the clutch device 40 is controlled by the clutch instruction pressure P (target value of the hydraulic pressure of the clutch device 40), which will be described later.

[0042] <Regarding the power transmission path> Next, I will explain the power transmission path.

[0043] As shown in Figure 1, when the vehicle 2 moves forward, the forward clutch 41 engages and the reverse clutch 49 is released. Power input from the engine 3 to the input shaft 13 via the torque converter 12 is transmitted from the input shaft gear 14 to the primary shaft 21 via the primary input gear 22 when the forward clutch 41 is engaged. On the other hand, even when the power input to the input shaft 13 is transmitted from the input shaft gear 14 to the secondary input gear 24 and the secondary input gear 24 rotates, the release of the reverse clutch 49 causes the secondary input gear 24 to spin freely relative to the secondary shaft 23, and no power is transmitted to the secondary shaft 23.

[0044] The power transmitted to the primary shaft 21 is shifted according to a belt gear ratio corresponding to the pulley ratio between the primary pulley 26 and the secondary pulley 27, and then transmitted to the secondary shaft 23. The power transmitted to the secondary shaft 23 is then transmitted from the secondary output gear 25 to the output shaft 15 via the output shaft gear 16.

[0045] When vehicle 2 moves in reverse, the forward clutch 41 is released and the reverse clutch 49 is engaged. Power input from engine 3 to input shaft 13 via torque converter 12 is transmitted from input shaft gear 14 to secondary shaft 23 via reverse transmission mechanism 30 and secondary input gear 24 due to the engagement of reverse clutch 49. At this time, secondary shaft 23 rotates in the opposite direction to when the vehicle moves forward. Power transmitted to secondary shaft 23 is transmitted from secondary output gear 25 to output shaft gear 16 to output shaft 15.

[0046] On the other hand, even when the power input to the input shaft 13 is transmitted from the input shaft gear 14 to the primary input gear 22, causing the primary input gear 22 to rotate, the release of the forward clutch 41 causes the primary input gear 22 to spin freely relative to the primary shaft 21, and no power is transmitted to the primary shaft 21.

[0047] <Regarding control devices and sensors> Next, with reference to Figure 2, the control device 1 and the sensors connected to the control device 1 will be described.

[0048] The control unit 1 includes multiple ECUs (Electronic control units), each containing a microcontroller. The microcontroller has built-in non-volatile memory, such as ROM or flash memory. Each ECU is connected to enable bidirectional communication using the CAN (Controller Area Network) communication protocol (see Figure 2).

[0049] As shown in Figure 2, the multiple ECUs include an engine ECU 50 for engine control and a transmission ECU 51 for gear shift control. The multiple ECUs also include a brake ECU (not shown) for brake control, etc. An output determination unit 52 is connected to the engine ECU 50. Various sensors necessary for control are connected to the engine ECU 50 and the transmission ECU 51.

[0050] The engine ECU 50 is connected to the throttle valve 4 and the engine speed sensor 53, among other things.

[0051] The engine ECU 50 controls the throttle valve 4, injectors, spark plugs, and starter, etc., for starting, stopping, and adjusting the output of the engine 3, based on information obtained from detection signals from various sensors and / or various information input from other ECUs. The engine ECU 50 can detect the amount of accelerator pedal depression using appropriate sensors and control the throttle valve 4, etc., accordingly. In addition, the engine ECU 50 can perform various controls, such as fuel supply amount, based on the engine speed obtained by the engine speed sensor 53, which will be described later. In addition to the above, the engine ECU 50 can also perform control that suppresses fuel supply (also called fuel cut).

[0052] The engine rotation sensor 53 outputs a pulse signal synchronized with the rotation of the engine 3 as a detection signal. The engine ECU 50 converts the frequency of the pulse signal input from the engine rotation sensor 53 into engine speed. Note that the engine speed may be obtained not only directly by the engine rotation sensor 53, but also indirectly by other means.

[0053] The transmission ECU 51 is connected to a turbine rotation sensor 60, an output shaft rotation sensor 61, and a clutch pressure sensor 62, among others.

[0054] The turbine rotation sensor 60 outputs a pulse signal as a detection signal that is synchronized with the rotation of the turbine runner of the torque converter 12 (see Figure 1). Since the frequency of this pulse signal corresponds to the rotational speed of the turbine runner, the transmission ECU 51 converts the frequency of the pulse signal input from the turbine rotation sensor 60 into the turbine rotational speed. Since the turbine runner and the input shaft 13 rotate together, the turbine rotational speed is the same as the rotational speed of the input shaft 13. Here, the turbine rotational speed decreases from its peak as the torque transmission capacity of the clutch 41 increases with the engagement of the clutch 41. Furthermore, when the clutch 41 is fully engaged, the decrease in the turbine rotational speed stops and it matches the rotational speed of the input shaft 13.

[0055] The output shaft rotation sensor 61 outputs a pulse signal as a detection signal that is synchronized with the rotation of the output shaft 15. Since the frequency of this pulse signal corresponds to the rotational speed of the output shaft 15, the transmission ECU 51 converts the frequency of the pulse signal input from the output shaft rotation sensor 61 to the output shaft rotational speed.

[0056] The clutch pressure sensor 62 outputs a pulse signal as a detection signal that is synchronized with the hydraulic pressure in the hydraulic chamber 45 of the clutch device 40. Based on the frequency of this pulse signal, the hydraulic pressure of the clutch device 40 is detected. The control device 1 can also (detect) and determine, based on the output value of the hydraulic pressure detected by the clutch pressure sensor 62, that the clutch device 40 (forward clutch 41) has transitioned from a contact state to a state in which power transmission is estimated to be possible.

[0057] The transmission ECU 51 controls valves (not shown) included in the hydraulic circuit for supplying oil to various parts of the transmission unit 10, based on information obtained from detection signals from various sensors and / or various information input from other ECUs. The valves include solenoid valves for controlling the hydraulic pressure of the forward clutch 41 and the reverse clutch 49. The solenoid valves used are valves capable of controlling the output hydraulic pressure by the current value, such as normally open type linear solenoid valves. The output hydraulic pressure of the solenoid valve is controlled according to the output value of the solenoid.

[0058] <About clutch operation> Next, referring to Figures 3 and 4, the operation of the forward clutch 41 will be explained below based on Figures 3 and 4. Since the configurations of the forward clutch 41 and the reverse clutch 49 are similar, the forward clutch 41 will be used as an example in the following explanation.

[0059] As shown in Figure 3(a), the cushioning material 47 is positioned between the clutch piston 43 and the friction material 44, preventing direct contact between the clutch piston 43 and the friction material 44.

[0060] As shown in Figure 3(b), the clutch piston 43 is pressed toward the cushioning material 47 by the oil supplied to the hydraulic chamber 45. The clutch piston 43 comes into contact with the cushioning material 47 by hydraulic pressure. Here, the cushioning material 47 has a predetermined elastic force, and as the clutch piston 43 moves toward the friction material 44, it biases the clutch piston 43 toward the rear Rr side with a predetermined elastic force. This suppresses the occurrence of engagement shock when the clutch piston 43 engages.

[0061] As shown in Figure 4(c), when oil is supplied to the hydraulic chamber 45 and the hydraulic pressure rises, the clutch piston 43 moves forward Fr and presses the friction material 44 from the rear Rr via the cushioning material 47. Furthermore, by pressing and compressing the cushioning material 47, the clutch piston 43 can crush the cushioning material 47 against its elastic force. As a result, the clutch piston 43 can reliably transmit power to the friction material 44.

[0062] Furthermore, as shown in Figure 4(d), when the hydraulic pressure in the hydraulic chamber 45 increases further, the cushioning material 47 is completely compressed, the friction material 44 is pressed against it, and the forward clutch 41 is fully engaged. On the other hand, when the hydraulic pressure is released from the engaged state of the forward clutch 41, the biasing force of the return spring 46 moves the clutch piston 43 to the rear Rr, releasing the pressure of the friction material 44 and disengaging the forward clutch 41.

[0063] <About clutch engagement control> Next, the engagement control of the forward clutch 41 when the gear range in the continuously variable transmission 20 is switched from a non-driving range to a driving range will be described. In this embodiment, the example described is when the gear range is in a non-driving range (e.g., N range), the accelerator pedal is pressed down and the engine output is increased (also referred to as the racing garage), and the gear range is shifted to the driving range (e.g., D range). In this embodiment, the engagement control of the forward clutch 41 (also referred to simply as clutch 41) in the racing garage will be described. Before describing the engagement control of the engine 3, the meaning of each term will be explained below.

[0064] "Clutch instruction pressure P" is the target value for the hydraulic pressure of the clutch 41. More specifically, clutch instruction pressure P is the target value for the hydraulic pressure of the hydraulic chamber 45 provided in the clutch 41.

[0065] "Engine speed" refers to the rotational speed of engine 3, as detected by the engine speed sensor 53.

[0066] "Turbine rotation speed" refers to the turbine rotation speed obtained by detection by the turbine rotation sensor 60.

[0067] "Clutch engagement degree" refers to the degree of engagement of the clutch 41. In this embodiment, the clutch engagement degree changes as the clutch piston 43 advances in accordance with the hydraulic pressure (solenoid output), as described above. In this embodiment, the clutch engagement degree also changes according to the clutch instruction pressure P described above. In the following description, the clutch engagement degree may be simply referred to as the engagement degree.

[0068] The above is an explanation of each term. Next, we will explain the clutch engagement control of the clutch 41 when the shift range is switched from the non-driving range to the driving range while the output of the engine 3 is above a predetermined output (racing garage), referring to Figure 5. Figure 5 is a timing chart showing the clutch engagement control of the present invention in chronological order.

[0069] As shown in Figure 5, when the gear shift range is in the non-driving range (N range), the engine speed of the engine 3 increases when the accelerator pedal is pressed. In this state, when the gear shift range is switched to the driving range (D range) (timing T1), the output determination unit 52 determines whether the output of the engine 3 is equal to or greater than a predetermined output. Here, the output of the engine 3 includes values ​​obtained directly, such as the engine speed, and values ​​obtained indirectly from the turbine speed. In this embodiment, the case in which the determination of the output of the engine 3 is performed based on the engine speed will be explained as an example.

[0070] The control device 1 performs a first engagement step S1, which is the condition that the output determination unit 52 determines that the output (rotational speed) of the engine 3 is equal to or greater than a predetermined output (rotational speed). This control transitions the engagement degree of the clutch 41 to a standby engagement degree lower than the engagement degree that enables power transmission. The engagement control of the clutch 41 is performed by controlling the hydraulic pressure with a clutch instruction pressure P corresponding to the standby engagement degree. Here, the condition for determining that the rotational speed of the engine 3 is equal to or greater than a predetermined rotational speed is, for example, a state in which the engine rotational speed has increased due to accelerator operation (racing garage). Therefore, in the first engagement step S1, if the engine rotational speed is equal to or greater than a predetermined rotational speed (a state in which the engine rotational speed is high), the engagement degree of the clutch 41 is controlled to engage to a standby engagement degree lower than the engagement degree that enables power transmission. As a result, the control device 1 can suppress clutch squeal (abnormal noise) and clutch 41 engagement shock (garage shock).

[0071] As described above, the standby engagement degree is, for example, the state estimated to be just before power transmission becomes possible. Specifically, it is the engagement degree at which the clutch 41 is in contact (see Figure 3(b)). That is, the standby engagement degree is the engagement degree at which the clutch piston 43 is in contact with the cushioning material 47. At this time, the engagement of the clutch 41 is controlled by the clutch instruction pressure P to maintain the standby engagement degree. As a result, the control device 1 can quickly transition the engagement state (engagement degree) of the clutch 41 to the engagement degree at which the clutch 41 is in contact in the first engagement step S1. The engagement degree at which the clutch 41 is in contact can be set by experimentally determining it in advance or by obtaining it using the clutch pressure sensor 62.

[0072] Furthermore, in the first engagement step S1, control is performed to reduce the rotational speed of the engine 3 by, for example, suppressing the fuel supply (also called fuel cut) when it is estimated that the rotational speed of the engine 3 has reached its maximum. As a result, the control device 1 can smoothly reduce the rotational speed of the engine 3 to a predetermined rotational speed. Therefore, the control device 1 can quickly execute the control of the second engagement step S2, which is performed after the execution of the first engagement step S1, as described later. As a result, the control device 1 can suppress the occurrence of a time lag in gear shifting. Note that the control to reduce the rotational speed of the engine 3 can employ various means other than just suppressing the fuel supply, such as blocking the throttle opening.

[0073] In the first engagement step S1, instead of the engine speed, control may be performed to transition the engagement state of the clutch 41 to a state where hydraulic pressure is applied that does not draw in the turbine rotation in the torque converter 12. By adopting this configuration, the control device 1 can quickly transition in the first engagement step S1 to an engagement state (degree of engagement) that is estimated to be just before power transmission becomes possible. Here, the state in which hydraulic pressure is applied that does not draw in the turbine rotation in the torque converter 12 can be set by experimentally determining it in advance or by obtaining it with the clutch pressure sensor 62.

[0074] Once the control in the first engagement step S1 is completed, the control in the second engagement step S2 is executed at timing T2. Specifically, first, the output determination unit 52 determines that the rotational power input to the clutch 41 is lower than a predetermined reference value, and then controls are performed to improve the engagement of the clutch 41 to a state where power transmission is possible. This control to improve the engagement of the clutch 41 is performed by increasing the clutch instruction pressure P. Here, the predetermined reference value is set, for example, to the engine speed at which no abnormal noise occurs in the clutch 41 when the clutch 41 is engaged, or to the engine speed at which no engagement shock occurs in the clutch 41. These engine speeds can be set based on data obtained in advance through experiments or output values ​​obtained from the engine speed sensor 53, etc.

[0075] The condition for initiating the second engagement step S2 is determined to be that the second output (second rotational speed) of the engine 3 is lower than the first output (first rotational speed) in the first engagement step S1. With this configuration, the control device 1 can suppress the clutch 41 from engaging when the engine 3's rotational speed is high. As a result, the control device 1 can suppress the generation of abnormal noise and engagement shock from the clutch 41.

[0076] In the clutch engagement control in the second engagement step S2, the cushioning material 47 is pressed and compressed by the clutch piston 43 (see Figure 4(c)). Subsequently, the cushioning material 47 is further pressed and fully engaged (Figure 4(d)). As a result, the clutch 41 is fully engaged. In this way, the control device 1 can improve the engagement of the clutch 41 to a state where power transmission is possible, provided that it determines that the rotational power input to the clutch 41 is lower than a predetermined reference value. Therefore, the control device 1 of the present invention can effectively suppress abnormal noise and engagement shock of the clutch 41.

[0077] As described above, the control device 1 of the present invention can, in the first engagement step S1, quickly proceed to the state in the clutch 41 that is estimated to be just before power transmission becomes possible, while suppressing abnormal noise and engagement shock of the clutch 41. Therefore, the control device 1 of the present invention can quickly transition to the second engagement step S2 that is executed thereafter, and can safely engage the clutch (transmit power).

[0078] The above describes an embodiment of the control device 1 according to the present invention. However, the control device 1 of the present invention is not limited to the embodiment described above, and can be modified in various ways.

[0079] In this embodiment, the forward clutch 41 has been described, but the control device 1 of the present invention can be applied not only to the forward clutch 41 but also to various clutch devices 40, including the reverse clutch 49. Furthermore, the output determination unit 52 may not be provided separately from the engine ECU 50, but may be included in the engine ECU 50 or other ECUs. In addition, the clutch instruction pressure P in the first engagement step S1 and the second engagement step S2 can be set to an appropriate instruction pressure depending on the characteristics of the engine 3, clutch device 40, and continuously variable transmission 20.

[0080] Furthermore, in this embodiment, the P range and N range were given as examples of non-driving ranges in the continuously variable transmission 20, but the control device 1 of the present invention can employ various gear ranges selected when the vehicle 2 is not in a driving state. Also, in this embodiment, the D range was given as an example of a driving range in the continuously variable transmission 20, but the control device 1 of the present invention can employ various gear ranges selected when the vehicle 2 is in a driving state (for example, the S range and the B range).

[0081] Furthermore, in this embodiment, the output determination of the engine 3 in the output determination unit 52 is performed based on the engine speed. However, the control device 1 of the present invention is not limited to this, and can perform the output determination of the engine 3 based on various conditions correlated with the output of the engine 3. For example, the control device 1 of the present invention can start the second engagement step S2 on the condition that a predetermined time has elapsed since the start of the engagement control of the clutch 41 in the first engagement step S1. With this configuration, the control device 1 of the present invention can suppress the start of clutch 41 engagement in a region where the output of the engine 3 is high. That is, by elapsed a predetermined time since the start of clutch 41 engagement control, the clutch 41 can be started to engage when the output of the engine 3 has decreased. As a result, the control device 1 of the present invention can suppress the generation of abnormal noise and engagement shock of the clutch 41.

[0082] Furthermore, the output determination of the engine 3 in the output determination unit 52 may be based not only on directly acquired outputs such as engine speed, but also on indirectly acquired outputs. For example, the output determination of the engine 3 may be performed indirectly based on the turbine speed of the torque converter 12. With this configuration, the control device 1 of the present invention can perform highly accurate engagement control of the clutch 41 based on the turbine speed correlated with the output of the engine 3. The turbine speed can be acquired, for example, by a turbine rotation sensor 60 provided in the torque converter or the like.

[0083] In this embodiment, a hydraulically controlled clutch is used as the clutch device 40, but the control device 1 of the present invention is not limited to this, and can use various types of clutch devices 40. For example, the clutch device 40 may be an electromagnetically controlled clutch.

[0084] In this embodiment, the clutch device 40 reduces engagement shock with a cushioning material 47, but various elastic members can be used instead of the cushioning material 47. For example, the elastic member 47 may be made of a spring. Also, in this embodiment, the transition to a contact state in which the cushioning material 47 and the clutch piston 43 come into contact is used as the determination condition for switching to the first engagement step S1, but the control device 1 of the present invention is not limited to this. Various conditions can be set as the determination condition, as long as the clutch 41 is in an engagement state (degree of engagement) without clutch squeal or engagement shock. For example, the determination condition may be set based on the elapsed time since switching the gear range, the turbine rotation speed, the hydraulic pressure (clutch pressure) of the clutch device 40, etc.

[0085] Furthermore, in this embodiment, fuel supply is suppressed (fuel cut) in the first engagement step S1 to reduce engine output, but the timing of suppressing fuel supply can be appropriately changed according to engine characteristics, etc. Also, in this embodiment, the timing of releasing the fuel supply suppression is performed simultaneously with the start of the second engagement step S2 (timing T2), but the timing of releasing the fuel supply suppression can be appropriately changed. In addition, the means for reducing engine output is not limited to fuel supply suppression, but various means such as blocking the throttle opening can be employed. Furthermore, the means for reducing engine output may be provided as needed, and it is also possible to omit the means for reducing engine output.

[0086] Furthermore, although this embodiment shows a vehicle 2 (CVT vehicle) equipped with a continuously variable transmission 20 as an example, the control device 1 of the present invention may be used in vehicles other than CVT vehicles, such as AT vehicles. In other words, the control device 1 of the present invention can be used with various types of transmissions. Also, the clutch device 40 is not limited to the forward clutch 41 and reverse clutch 49 of a CVT vehicle, but may also be the clutch device of an AT vehicle.

[0087] The above describes various embodiments and modifications of the control device according to the present invention. However, the present invention is not limited to those exemplified in the embodiments and modifications described above, and it will be readily apparent to those skilled in the art that other embodiments may exist in the spirit and teachings thereof, without departing from the scope of the claims. [Industrial applicability]

[0088] The control device of the present invention can be used for clutch engagement control in various vehicles equipped with an engine. [Explanation of symbols]

[0089] 1: Control device 2: Vehicles 3: Engine 40: Clutch device 41: Forward clutch (clutch, clutch device) 52: Output determination unit 53: Engine rotation sensor 60: Turbine rotation sensor 62: Clutch pressure sensor P: Clutch pressure S1: First engagement step S2: Second engagement step

Claims

1. A control device that controls the engagement of a clutch in a transmission to which power generated in the engine of a vehicle is input, The engine has an output determination unit that directly or indirectly determines the output of the engine, The clutch comprises a clutch piston, a friction material, and an elastic member disposed between the clutch piston and the friction material. When the gear range of the transmission is switched from a non-driving range selected in a non-driving state to a driving range selected in a driving state, A first engagement step in which, provided that the output determination unit determines that the engine output is equal to or greater than a predetermined output, the engagement degree of the clutch is set to a standby engagement degree lower than the engagement degree that enables power transmission, The clutch engagement control is performed by, under the condition that the rotational power input to the clutch is lower than a predetermined reference value, improving the degree of engagement of the clutch so that power transmission is possible in the clutch, and then, In the first engagement step, the fuel supply to the engine is suppressed, and the suppression of fuel supply is stopped simultaneously with the start of the second engagement step. A control device characterized in that the standby engagement degree in the first engagement step is the engagement degree in which the clutch piston and the elastic member constituting the clutch come into contact, but before the elastic member presses against the friction material.

2. The control device according to claim 1, characterized in that the second engagement step is initiated on the condition that it is determined to be less than or equal to a second output which is lower than the first output of the engine in the first engagement step.

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