Chitted clutch engagement control system

Abstract

A clutch actuator (5) moves a first clutch member (11) and a second clutch member (12) of a fitting clutch (10) relative to each other in the axial direction, a phase difference sensor (6) detects the phase difference between the first clutch member (11) and the second clutch member (12), and a control device (7). The control device (7) performs a synchronization operation for gradually reducing the difference in rotational speed of the input / output shaft to reach a target rotational speed difference ([omega] s), and detects the current engagement timing on the basis of the output of the phase difference sensor (6), and after an adjustment reference time (t1) at which the difference in rotational speed of the input / output shaft reaches a rotational speed difference ([omega] 0) at which the phase difference can be detected by the phase difference sensor (6), the control device (7) performs a synchronization operation for gradually reducing the difference in rotational speed of the input / output shaft to reach the target rotational speed difference ([omega] s). On the basis of the information acquired at the arbitrary phase difference detection time (td), the phase difference is adjusted by changing the change characteristics of the rotational speed difference of the input / output shaft such that any one of the future engagement periods matches the completion target time (tall).

Description

Cross-reference of related applications

[0001] This application is based on Japanese Application No. 2023-185557, filed on October 30, 2023, the contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to a clutch engagement control system. Background Technology

[0003] Conventional systems exist for engaging clutches that engage input and output shafts rotating at different speeds in the released state. For example, Patent Document 1 discloses a technique for predicting future engagement times based on past engagement periods (engagement timing) detected by a phase difference sensor. The control device synchronizes the speed difference between the motor and the axle (i.e., the input / output shaft speed difference) to a predetermined target speed difference. Furthermore, the clutch actuator is pre-driven to engage the clutch at the predicted engagement time after the input / output shaft speed difference reaches the target speed difference.

[0004] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2021-025561 Summary of the Invention

[0005] In the technology of Patent Document 1, the control device stores multiple past engagement times and calculates approximate lines passing through each point to predict future engagement times. Since future engagement times are predicted approximately from past engagement times, the error with the actual operation increases. As a result, the phase matching time from when the input / output shaft speed difference reaches the target speed difference until engagement is performed becomes longer, and the responsiveness to engagement instructions decreases.

[0006] The purpose of this disclosure is to provide a clutch engagement control system that achieves high-precision adjustment of the phase difference between the input and output shafts and improves the responsiveness of clutch engagement.

[0007] The engagement control system of the engagement clutch disclosed herein includes an engagement clutch, a clutch actuator, a phase difference sensor, and a control device.

[0008] The engagement clutch has a first clutch component and a second clutch component, which switch the engagement and disengagement states of the first clutch component and the second clutch component. The first clutch component is connected to the input shaft and has a plurality of first engagement teeth arranged in the circumferential direction. The second clutch component is connected to the output shaft and has a plurality of second engagement teeth arranged in the circumferential direction, which can engage with the first engagement teeth directly or via a relay component.

[0009] In a vehicle-mounted clutch engagement control system, the input shaft is connected to a motor or internal combustion engine, for example, via a reducer. The output shaft is connected to the drive wheels via an axle.

[0010] The clutch actuator causes the first clutch assembly and the second clutch assembly to move axially relative to each other, or, in the case of a relay assembly, causes the relay assembly to move axially relative to both the first and second clutch assemblies. A phase difference sensor detects the phase difference between the first and second clutch assemblies.

[0011] The control device controls the difference between the input shaft speed and the output shaft speed, i.e., the input-output shaft speed difference. Based on the engagement instruction to engage the released clutch, the control device performs a synchronization action to gradually reduce the input-output shaft speed difference to the target speed difference that allows the clutch to engage.

[0012] During synchronization, the control device detects the current engagement period based on the output of the phase difference sensor for the engagement period of the phase difference that enables the clutch to engage, and outputs a drive instruction to the clutch actuator so that the clutch engages at a future engagement period after the input-output shaft speed difference reaches the target speed difference.

[0013] After adjusting the reference time, the control device, based on information obtained at an arbitrary phase difference detection time (when any phase difference is detected according to the output of the phase difference sensor), adjusts the phase difference between the first and second clutch components by changing the characteristics of the input / output shaft speed difference variation in a way that ensures a future engagement period coincides with the target completion time. The reference time is the moment when the input / output shaft speed difference reaches a point where the phase difference sensor can detect the phase difference. The target completion time is the time after the target time has elapsed since the reference time. For example, the arbitrary phase difference detection time is the initial engagement period detection time after the reference time has been adjusted.

[0014] In the phase difference adjustment disclosed herein, the "change characteristic of the input-output shaft speed difference" that is modified is, for example, the time change rate of the input-output shaft speed difference, i.e., the "gradient," or the "target speed difference." In this disclosure, by changing the change characteristic of the input-output shaft speed difference in the synchronization operation, phase difference adjustment can be achieved with high precision, thereby improving the responsiveness of clutch engagement.

[0015] Here, the timing at which the input / output shaft speed difference reaches the target speed difference during synchronization is defined as the arrival period. After predicting the future engagement period, control is assumed to be applied in a manner that brings the engagement period close to the arrival period. In this case, if torque is input to the input shaft to bring the engagement period close to the arrival period, the input shaft speed changes, causing the arrival period to deviate, potentially reducing the accuracy of phase difference adjustment. In contrast, in this disclosure, based on information obtained at any phase difference detection moment, the characteristics of the input / output shaft speed difference change and phase difference adjustment are simultaneously performed, thus enabling high-precision phase difference adjustment. Furthermore, in this disclosure, it is not necessary to predict the future engagement period. Attached Figure Description

[0016] The foregoing and other objects, features, and advantages of this disclosure will become more apparent from the accompanying drawings and from the detailed description that follows.

[0017] Figure 1 This is a diagram illustrating the structure of a vehicle that utilizes an interlocking clutch engagement control system.

[0018] Figure 2 This is a diagram illustrating the switching between 2WD and 4WD.

[0019] Figure 3 This is a time diagram showing the switching action from 2WD to 4WD based on the comparative example and the control of this embodiment.

[0020] Figure 4 This is a schematic diagram illustrating the state transition of an engaged clutch.

[0021] Figure 5 This is a structural diagram of the engagement control system of the interlocking clutch in this embodiment.

[0022] Figure 6 This is a block diagram of the control device.

[0023] Figure 7 This is a diagram illustrating the detection principle of a phase difference sensor.

[0024] Figure 8 This is a diagram showing the beat waveform output by the phase difference sensor.

[0025] Figure 9 This is a timeline of the synchronization actions in the first implementation method.

[0026] Figure 10 The phase difference adjustment in the first embodiment ( Figure 9 The timeline after the adjustment of the reference time t1.

[0027] Figure 11 This is a flowchart of the clutch engagement control in the first embodiment.

[0028] Figure 12 This is a time diagram of phase difference adjustment in the second embodiment.

[0029] Figure 13 This is a time diagram of phase difference adjustment in the third embodiment.

[0030] Figure 14 This is a time diagram of phase difference adjustment in the fourth embodiment.

[0031] Figure 15 This is a time diagram of phase difference adjustment in the fifth embodiment.

[0032] Figure 16 This is a time diagram of phase difference adjustment in the sixth embodiment.

[0033] Figure 17 This is a timing diagram of the phase difference adjustment in the seventh embodiment.

[0034] Figure 18 This is a provisional time diagram of the phase difference adjustment of td1 during the first phase difference detection in the eighth embodiment.

[0035] Figure 19 This is a provisional time diagram of the phase difference adjustment of td2 during the second phase difference detection in the eighth embodiment.

[0036] Figure 20 This is the final time diagram of the phase difference adjustment of td3 during the third phase difference detection in the eighth embodiment.

[0037] Figure 21 This is a flowchart of the clutch engagement control in the eighth embodiment. Detailed Implementation

[0038] Based on the accompanying drawings, a clutch engagement control system with multiple embodiments will be described. The first to eighth embodiments share the same basic system structure, but differ in the control structure of the control device. The first to eighth embodiments are collectively referred to as "this embodiment". The clutch engagement control system of this embodiment is a system that engages the clutch by driving the clutch actuator according to the engagement timing when the clutch in the powertrain of a vehicle is in the released state.

[0039] [Vehicle, Clutch Engagement Control System] Reference Figure 1 , Figure 2This section describes a structural example of a vehicle 90 that utilizes an engagement control system for a clutch. This vehicle 90 is an electric vehicle powered by two MGs (electric generators): MG81 for the front wheels and MG82 for the rear wheels. MG81 and 82 function as both electric motors during power operation and generators during regenerative braking. The vehicle 90 can switch between two-wheel drive (2WD) powered only by the front wheels 91 and four-wheel drive (4WD) powered by both the front wheels 91 and the rear wheels 92.

[0040] The front wheel MG81 is always connected to the front wheel 91 via a differential gear 93 and a connecting shaft 95. Therefore, the front wheel 91 is always the drive wheel. On the other hand, a clutch 10 is provided in the power transmission path from the rear wheel MG82 to the rear wheel 92. Figure 1 In the example shown, an engaging clutch 10 is provided between the rear wheel MG82 and the differential gear 94, but the engaging clutch 10 can also be provided on the side of the rear wheel 92 closer to the differential gear 94.

[0041] When the engagement clutch 10 is in the disengaged state, the rear wheel MG82 is not connected to the rear wheel 92, and the rear wheel 92 rotates as the driven wheel of the front wheel 91. When the engagement clutch 10 is in the engaged state, the rear wheel MG82 is connected to the rear wheel 92 via the differential gear 94 and the connecting shaft 96. At this time, in addition to the front wheel 91, the rear wheel 92 also becomes a drive wheel. Furthermore, reducers 87 and 88 can be installed on the output shafts of both the front wheel MG81 and the rear wheel MG82.

[0042] Thus, by switching between the disengaged and engaged states of the clutch 10, the vehicle 90 switches between 2WD and 4WD. For example, it selects 1MG in 2WD for driving on a flat road with low load, and selects 2MG in 4WD for driving on a slope requiring high traction. When switching from 4WD to 2WD, it is necessary to reduce drag loss and improve power consumption by disengaging the clutch. When switching from 2WD to 4WD, it is necessary to have good acceleration performance based on the high-response clutch engagement. If the clutch engagement is delayed, the torque response of the disengaged rear wheel using MG82 is delayed, and the torque response of the entire vehicle is delayed. As a result, the torque response delay relative to the driver's accelerator operation affects driving performance.

[0043] When a higher-level vehicle control unit (not shown) determines that a switch from 2WD to 4WD is needed based on the vehicle's driving status, external environment such as road surface, or driver instructions, it sends an engagement instruction to the clutch engagement control system 100. Upon receiving the engagement instruction while the clutch 10 is disengaging, the clutch engagement control system 100 engages the clutch 10. The clutch engagement control system 100 includes the clutch 10, a clutch actuator 5, a phase difference sensor 6, and a control device 7. In the following description and drawings, the clutch actuator 5 is sometimes appropriately referred to as "ACT".

[0044] The engagement clutch 10 has a first clutch component 11 connected to the input shaft 3 and a second clutch component 12 connected to the output shaft 4. The first clutch component 11 has a plurality of first engagement teeth 13 arranged circumferentially and rotates about its axis. The second clutch component 12 has second engagement teeth 14 formed circumferentially, capable of directly meshing with the first engagement teeth 13, and is coaxial with the first clutch component 11 and rotates in the same direction. Figure 1 In this structural example, a reducer 88 is provided between the rear wheel MG82 and the first clutch component 11. The rotation of the motor shaft 83 of the rear wheel MG82 is reduced by the reducer 88 and transmitted to the input shaft 3.

[0045] The clutch actuator 5 causes the first clutch component 11 and the second clutch component 12 to move relative to each other in the axial direction. The clutch actuator 5 is not limited to being located on the side of the first clutch component 11, but may also be located on the side of the second clutch component 12. If the first clutch component 11 and the second clutch component 12 move toward each other, they are in an engaged state where the first engagement tooth 13 and the second engagement tooth 14 are engaged. If the first clutch component 11 and the second clutch component 12 move toward each other, they are in a released state where the engagement is disengaged. That is, the engagement and release states of the first clutch component 11 and the second clutch component 12 are switched by the axial relative movement of the first clutch component 11 and the second clutch component 12. Furthermore, a sleeve-type clutch, different from this type of clutch, is described in the "Other Embodiments" section.

[0046] When the input shaft 3 and output shaft 4 rotate at different speeds in the released state of the engagement clutch 10, the phase difference sensor 6 detects the phase difference between the first clutch component 11 and the second clutch component 12, that is, the phase difference between the input shaft 3 and the output shaft 4, and outputs the phase difference sensor signal to the control device 7. The engagement control system 100 of this embodiment is mounted on a vehicle 90 whose output shaft 4 is connected to the rear wheel 92, which serves as the drive wheel.

[0047] Hereinafter, the "period of phase difference during which the engaging clutch 10 can engage" will be referred to as the "engagement period". The "engagement period" includes not only the period during which an engagement action is actually performed, but also multiple periods during which engagement is possible but not performed. The control device 7 detects the current engagement period based on the phase difference sensor signal and outputs a drive instruction to the clutch actuator 5 according to the future engagement period. In detail, the control device 7 initiates the pre-action action of the clutch actuator 5 a predetermined pre-action time before the future engagement period. In addition, the control device 7 controls the difference between the rotational speed of the input shaft 3 and the rotational speed of the output shaft 3, i.e., the input-output shaft speed difference, by controlling the rotation of the rear wheel MG82. Hereinafter, the symbols for "input shaft 3" and "output shaft 4" related to rotational speed will be omitted as appropriate.

[0048] Reference Figure 3 , Figure 4 This describes the typical engagement action when switching from 2WD to 4WD. Figure 3 The diagram illustrates the changes in input / output shaft speeds and ACT stroke based on the comparative example and this embodiment. To compare with... Figure 9 The time symbols such as t1 used in the equation are used to distinguish them. Figure 3 The symbols “τ0~τ5” are used for the time intervals. The length of the period IV between the control time intervals τ3~τ4 in the comparative example and this embodiment is different. During the period I between the time intervals τ0~τ1, the control device 7 receives a switching instruction and determines the start of the switching operation. Based on the switching instruction from 2WD to 4WD, an “engagement instruction to engage the released clutch” is generated.

[0049] According to the engagement instruction, during period II (τ1~τ2), control device 7 drives the rear wheel using MG82 to synchronize the rotation of input shaft 3 with the rotation of output shaft 4, causing the input shaft speed Nin to increase towards the output shaft speed Nout. The output shaft speed Nout is equivalent to the axle speed proportional to the vehicle speed. The action of matching the input shaft speed Nin with the output shaft speed Nout is called the "synchronization action." During periods I and II, the engaging clutch 10 is... Figure 4 In the released state, the engaging teeth 13 and 14 are separated from each other.

[0050] The target speed N_tgt of the input shaft speed Nin is set such that the difference ΔN between it and the output shaft speed Nout becomes the allowable range for engagement impact. Engagement is performed at a timing (i.e., engagement period) when the input shaft speed Nin reaches the target speed N_tgt, the input-output shaft speed difference ΔN becomes the target speed difference ωs or less, the ACT stroke reaches the standby stroke Stsb, and engagement occurs at a phase difference that allows engagement. Hereinafter, "input-output shaft speed difference" will be omitted and referred to as "speed difference". The speed difference is defined as 0 or a positive value. Furthermore, the sign of "ωs" will be explained later. Figure 9 , Figure 10 The explanation will be discussed later.

[0051] When the target speed N_tgt of the input shaft speed Nin is reached at time τ2, a drive instruction is output to the clutch actuator 5. During the period III from time τ2 to τ3, the ACT stroke changes from 0 to the standby stroke Stsb, and the engaging clutch 10... Figure 4 The released state moves towards the standby position. In the standby position, for example, the top surfaces of the engaging teeth 13 and 14 are in contact with each other, forming a state without gaps.

[0052] During the period IV from time τ3 to τ4, phase matching is performed between the first clutch component 11 and the second clutch component 12. When phase matching is complete and engagement is possible, during the period V from time τ4 to τ5, the ACT stroke changes from the standby stroke Stsb to the full stroke Stfl, and the engaging clutch 10... Figure 4 The clutch moves from the standby position to the fully engaged state. The sum of periods III, IV, and V constitutes the clutch operation period.

[0053] In existing technologies that approximate future engagement times based on past engagement times, the error with the actual operation widens, and the phase matching time becomes longer. The phase matching time within the clutch actuation time becomes dominant, reducing responsiveness to engagement instructions. Therefore, in this embodiment, the objective is to shorten the phase matching time through phase difference adjustment control. This achieves highly responsive switching from 2WD to 4WD based on clutch engagement.

[0054] Reference Figures 5-8 The structure of the engagement control system for the interlocking clutch in this embodiment will be described below. Figure 5 Focusing solely on the clutch engagement at the rear wheel 92 side of vehicle 90, the rear wheel is simply referred to as "MG82" (MG82 in this context). The speed of MG82 is detected by a speed sensor 23 (such as a rotary transformer), multiplied by the reduction ratio of the reducer 88, and converted into the speed of the input shaft 3. Figure 5 In the process, the converted input shaft speed Nin is input to the control device 7. On the other hand, the speed of the output shaft 4 is detected by the speed sensor 24, such as the wheel speed sensor, and is input as the converted output shaft speed Nout.

[0055] The phase difference sensor 6 is composed of, for example, a magnetic detection element such as a Hall element and a magnet. The phase difference sensor 6 uses the axial position across the first engagement tooth 13 and the second engagement tooth 14 as the detection range SA (see reference). Figure 7The phase difference sensor 6 is configured to face the clutch axis Z from the radially outer side without interfering with the engagement clutch 10. The phase difference sensor 6 detects the total area of ​​the first engagement tooth 13 and the second engagement tooth 14 passing through the detection range SA as they rotate, based on the change in magnetic induction intensity.

[0056] The pitch angle P is the angle obtained by dividing the angle of one revolution of the first clutch component 11 and the second clutch component 12 (i.e., 360 degrees) by the number of teeth. For example, if the first engaging tooth 13 and the second engaging tooth 14 have 36 teeth, the pitch angle P is 10 degrees. Figure 7 In the example structure assuming 36 teeth, the phase difference range is expressed as ±5deg. Furthermore, definitions of phase difference that differ from this definition are described in the "Other Embodiments" section.

[0057] Figure 7 The upper diagram represents the general phase difference Δθ during rotation. The middle diagram represents the state where the rotational phases of the first engaging tooth 13 and the second engaging tooth 14 are aligned, i.e., "phase difference Δθ = 0". In this state, the first clutch component 11 and the second clutch component 12 cannot engage. The teeth of both the first engaging tooth 13 and the second engaging tooth 14 are included within the detection range SA, and the sensor output is at its maximum when the total area is at its maximum. The gaps of both the first engaging tooth 13 and the second engaging tooth 14 are included within the detection range SA, and the sensor output is at its minimum when the total area is at its minimum.

[0058] Figure 7 The diagram below illustrates a state where the rotational phases of the first engaging tooth 13 and the second engaging tooth 14 are offset by half the tooth pitch angle P, resulting in a "phase difference Δθ = ±(1 / 2)P (=±5deg)". In this state, the first clutch component 11 and the second clutch component 12 can engage. The tooth portion of one of the first engaging tooth 13 and the gap portion of the other engaging tooth 14 are included in the detection range SA. When the total area reaches the intermediate value between the maximum and minimum values, the sensor output is the intermediate value.

[0059] Return to Figure 5 The control device 7 switches the engagement or disengagement of the clutch 10 based on an external engagement or disengagement instruction. The control device 7 acquires the phase difference sensor signal, the input shaft speed Nin, and the output shaft speed Nout, and controls the rotation of MG82 based on this information, outputting a drive instruction to the clutch actuator 5. When the control device 7 receives an engagement instruction to engage the disengaged clutch 10, it rotates MG82, initiating a synchronization operation that causes the input shaft speed Nin to increase in a manner close to the output shaft speed Nout.

[0060] like Figure 6 As shown, the control device 7 includes a phase difference detection unit 71, a speed difference / gradient calculation unit 72, a current phase difference estimation unit 73, a speed difference change characteristic calculation unit, an MG speed calculation unit 75, an MG speed control unit 76, an ACT drive determination unit 77, an action delay time estimation unit 78, and a target completion time correction unit 79. The symbols Δθd, td, ac, ωsc, Tall, and Tpre in the figure... Figure 9 , Figure 10 This will be explained later in the description.

[0061] The phase difference detection unit 71 filters the output of the phase difference sensor 6 to remove variation components within a specified frequency band. For example... Figure 8 As shown, the output of the phase difference sensor after filtering is a beat waveform. The segment of the beat waveform corresponds to the phase difference (Δθ = ±(1 / 2)P) at which the engagement clutch 10 can engage. The phase difference detection unit 71 outputs the phase difference Δθd detected from the phase difference sensor output and the time td at which the phase difference Δθd is detected to the speed difference change characteristic calculation unit 74.

[0062] The speed difference / gradient calculation unit 72 calculates the speed difference between the input shaft speed Nin and the output shaft speed Nout, as well as the time-varying rate of change of the speed difference, i.e., the gradient. The gradient is the time-varying rate of change of the speed difference, calculated by dividing the speed difference by the elapsed time. Furthermore, the target value of the gradient in speed difference control is set as the "target gradient". The current phase difference estimation unit 73 estimates the current phase difference based on the cumulative value of the speed difference from a predetermined reference time to the present. When plotting the estimated phase difference at each time point, as shown... Figure 9 The subsequent diagrams show a sawtooth-like pattern. Therefore, it is possible to predict the phase difference at any future moment.

[0063] The speed difference change characteristic calculation unit 74 calculates the target gradient ac or the target speed difference ωsc based on information including the phase difference Δθd and time td obtained from the phase difference detection unit 71, as the speed difference change characteristic changed by control through phase difference adjustment. As the speed difference change characteristic, the gradient is changed in the first to fourth embodiments, and the target speed difference is changed in the seventh embodiment. In the fifth and sixth embodiments, both the gradient and the target speed difference are changed. Details will be described later in the descriptions of each embodiment.

[0064] The MG speed calculation unit 75 calculates the current MG speed based on the output of the speed sensor 23 and notifies the MG speed control unit 76. The MG speed control unit 76 controls the rotation of the MG 82 to realize the target gradient ac or target speed difference ωsc calculated by the speed difference change characteristic calculation unit 74.

[0065] exist Figure 6For convenience, the MG speed control unit 76 is described as part of the control device 7. However, in reality, the control device of the interlocking clutch engagement control system 100 functions in cooperation with other MG control devices to constitute the control device 7. The MG control device mainly aims at drive control during the regeneration of power operation of the rear wheel 92 after clutch engagement, and controls the power supply from the power source to the MG 82 through the operation of the inverter. In contrast, Figure 6 The MG speed control unit 76 is specifically designed to control the input shaft speed Nin during the synchronization operation before clutch engagement. In other words, at least a portion of the synchronization operation within the entire function of the MG control device corresponds to the MG speed control unit 76.

[0066] The ACT drive determination unit 77 drives the clutch actuator 5 in a forward direction in two stages according to the engagement instruction. First, the ACT drive determination unit 77 moves the clutch actuator 5 to the standby position before the engagement period. Then, when engagement is performed, the ACT drive determination unit 77 moves the clutch actuator 5 to the full stroke position, engaging the engagement clutch 10. Additionally, the ACT drive determination unit 77 drives the clutch actuator 5 in the reverse direction according to the release instruction, disengaging the engagement clutch 10.

[0067] In cases where delays occur in the operation of the clutch actuator 5, the operation delay time estimation unit 78 estimates the operation delay time. For example, the larger the time constant of the filtering process in the phase difference detection unit 71, the more delayed the phase difference detection. Furthermore, the greater the computational load on the CPU constituting the control device 7, the greater the processing delay and communication delay between CPUs via CAN, etc. Additionally, there are cases where the operating speed varies depending on the temperature of the clutch actuator 5. The operation delay time estimation unit 78 estimates the operation delay time of the clutch actuator 5 based on this information and adjusts the ACT advance action time Tpre according to the operation delay time. The adjusted ACT advance action time Tpre is fed back to the ACT drive determination unit 77.

[0068] Reference Figure 9 , Figure 10 The target completion time Tall is the time from the adjustment reference time t1 to the target completion time tall of engagement. The control device 7 starts the pre-action of the clutch actuator 5 at a pre-action time Tpre that is predetermined earlier than the target completion time tall. The target completion time Tall is a fixed value in principle, but in the event of a delay in the operation of the clutch actuator 5, the target completion time correction unit 79 corrects the target completion time Tall according to the operation delay time and outputs it to the speed difference change characteristic calculation unit 74.

[0069] The above is a description of the structure of the control device 7 in this embodiment. The control device 7 in this embodiment adjusts the phase difference by coordinating the change in rotational speed difference with the change in phase difference during synchronization, thereby shortening the phase matching time (see reference). Figure 3 The timing of the clutch engagement is adjusted to achieve a high level of responsiveness. Next, the specific structures for phase difference adjustment in each embodiment will be described in turn.

[0070] (First Implementation) Reference Figures 9-11 This will illustrate the phase difference adjustment in the first embodiment. Figure 9 In the diagram above, the overall duration of the synchronization operation as the input shaft speed Nin increases from 0 is shown, sequentially from the top of the diagram, as representing the input and output shaft speeds, speed difference, phase difference, and cumulative phase difference. Figure 10 In the diagram above, the period after adjusting the reference time t1 is shown in sequence as follows: speed difference, phase difference, ACT drive indication, and ACT stroke. Figure 9 The second and third figures and Figure 10 The time difference in rotational speed and phase difference shown in the first and second figures Figure 1 Some parts overlap, but the timelines differ. Figure 10 In the middle, the change ratio in phase difference adjustment Figure 9 It is shown in more detail and also includes supplementary information.

[0071] exist Figure 9 , Figure 10 In the diagram, solid lines represent the control in the first embodiment, while double-dotted lines represent the control in the comparative example where phase difference adjustment was not implemented. Additionally, shaded triangles represent the engagement period in the control of the first embodiment, while dashed triangles represent the engagement period in the control of the comparative example. In the first embodiment, engagement is performed at time 'tall' upon completion of the target; in the comparative example, engagement is performed at time 'tz'.

[0072] In the graph of input and output shaft speeds, N [rpm] is used as the symbol for the speed. In the graph of speed difference, ω [deg / sec] is used instead of ΔN, based on integration with the mathematical formula. The speed difference ΔN [rpm] is converted to ω [deg / sec] using equation (1). Therefore, the speed difference is treated as a quantity synonymous with the rate of change of phase difference (or angular velocity difference).

[0073] ω[deg / sec] =ΔN[rpm]×360[deg]÷60[sec]…(1) Reference in the graph of input and output shaft speeds Figure 3The symbol is used. The output shaft speed Nout is constant, and the input shaft speed Nin increases from the initial value of 0 to the output shaft speed Nout. When the input shaft speed Nin reaches a detectable speed N_sen at time t1, phase difference detection can be performed using the phase difference sensor 6. This time is set as the "adjustment reference time t1".

[0074] Furthermore, the target speed N_tgt is set such that the speed difference between it and the output shaft speed Nout is within the allowable range of engagement impact. This is achieved when the input shaft speed Nin reaches the target speed N_tgt and the ACT stroke reaches the idle stroke Stsb (refer to...). Figure 10 Engagement is performed during the engagement period following the initial engagement. The time when the input shaft speed Nin reaches the target speed N_tgt is time tt in the comparative example and time ts in the first embodiment.

[0075] With the output shaft speed Nout constant, the speed difference graph is equivalent to the graph of speeds reversed vertically. The detectable difference between the speed N_sen and the output shaft speed Nout corresponds to the "detectable speed difference ω0". The difference between the target speed N_tgt and the output shaft speed Nout corresponds to the "target speed difference ωs that the engagement clutch 10 can engage". The control device 7 controls the speed difference and performs a synchronization action to gradually reduce the speed difference to the target speed difference ωs according to the engagement instruction that engages the engagement clutch 10 in the released state.

[0076] Regarding the phase difference graph, with 36 teeth, the phase difference Δθ varies within ±5 degrees around 0 degrees. The sawtooth wave's hypotenuse is strictly curved, but for simplicity, it is represented as a straight line. In the phase difference graph, the dashed lines in the period prior to the reference time t1 indicate that the phase difference cannot be detected.

[0077] After adjusting the reference time t1, the time at which an arbitrary phase difference is detected based on the output of the phase difference sensor 6 is set as the "arbitrary phase difference detection time td". During synchronization, the control device 7 detects the current engagement period based on the output of the phase difference sensor 6. The phase difference detected at the arbitrary phase difference detection time td is denoted as Δθd, and the rotational speed difference at the phase difference detection time td is denoted as ωd. If the arbitrary phase difference detection time td is the current time, the engagement period illustrated after time td represents the future engagement period. The graph showing the change in phase difference after time td is interpreted as the graph depicted in the result. At time td, the control device 7 does not need to constantly predict future changes in phase difference. Furthermore, examples of preferred prediction of future phase differences will be described later in the eighth embodiment.

[0078] In this example, the phase difference Δθd detected at any phase difference detection time td is +5deg, which is equivalent to "the phase difference at which the engaging clutch 10 can engage". Figure 7 The phase difference that can be joined is expressed as "Δθd = ±5deg", but in equation (4) described later, if Δθd takes two values, the solution cannot be uniquely determined. Therefore, the domain of Δθd is defined as "-5deg < Δθd ≤ +5deg", excluding -5deg. In addition, the target phase difference Δθt at the time of joining is basically +5deg. Therefore, in this example, "Δθt - Δθd = 0". The slope of the line in the graph of the cumulative phase difference represents the rate of change of the phase difference ω [deg / sec].

[0079] The control device 7 outputs a drive instruction to the clutch actuator 5, causing the engagement clutch 10 to engage at a future engagement period after the speed difference reaches the target speed difference ωs. In this embodiment, the control device 7 adjusts the phase difference so that any future engagement period coincides with the time elapsed after the target time Tall from the adjustment reference time t1, i.e., the target time Tall. That is, the target time Tall becomes the target timing for performing engagement.

[0080] exist Figure 10 The third figure shows the ON / OFF state of the drive indication for clutch actuator 5. Figure 10 The bottom diagram shows the stroke of the clutch actuator 5. The control device 7 initiates the pre-action of the clutch actuator 5 at time tpre, a predetermined pre-action time Tpre before the target completion time tall. The clutch actuator 5 reaches the standby position of the standby stroke Stsb at time tsb. Then, when the target completion time tall is reached, the control device 7 moves the clutch actuator 5 to its full stroke Stfl, thus fully engaging the clutch 10.

[0081] Next, regarding the control of the speed difference, specifically, the control that modifies the time-varying rate of change of the speed difference, i.e., the gradient, as the "change characteristic of the input-output shaft speed difference" will be explained. In both the comparative example and the first embodiment, the initial gradient from the adjustment reference time t1 to any phase difference detection time td is set to a0. Here, the initial gradient a0 during phase difference detection is set such that its absolute value is smaller than the gradient a00 during the period from the start of the synchronization operation to the adjustment reference time t1 when phase difference detection is not performed, i.e., the slope is gentle. This setting is effective in shortening the phase difference detection time.

[0082] In the comparative example, the initial gradient a0 remains constant from the adjustment reference time t1 until the time tt when the speed difference reaches the target speed difference ωs. In contrast, in the first embodiment, the control device 7 calculates the target gradient ac, which is the target value of the gradient, based on information obtained at an arbitrary phase difference detection time td, and changes the initial gradient a0 to the target gradient ac. In the first embodiment, the initial engagement period after the adjustment reference time t1 is set to the arbitrary phase difference detection time td.

[0083] Control device 7 adjusts the phase difference by changing the gradient at any phase difference detection time td, so that any future engagement period coincides with the target completion time tall. If the arbitrary phase difference detection time td is set to the current time, in the first embodiment, control is performed so that the next engagement period, the upcoming first engagement period, coincides with the target completion time tall. When the control is such that the nth future engagement period coincides with the target completion time tall, n is referred to as the "adjustment cycle number". In the first embodiment, "n=1".

[0084] The absolute value of the target gradient ac is larger than the initial gradient a0, meaning the slope is set to be steep. Therefore, the arrival time ts when the speed difference reaches the target speed difference ωs is earlier than the arrival time tt of the comparative example. As a result, engagement is performed at the target time tall earlier than the engagement execution time tz in the comparative example, enabling power transmission. Thus, compared to the comparative example, a higher precision and more responsive clutch engagement is achieved.

[0085] The time symbols in the diagram are supplemented as follows: Td represents the initial gradient duration from the adjustment reference time t1 to the arbitrary phase difference detection time td. Ts represents the target gradient duration from the arbitrary phase difference detection time td to the arrival time ts. Tc represents the target rotational speed difference duration from the arrival time ts to the completion time tall. The sum of Td, Ts, and Tc equals the completion time tall (Td + Ts + Tc = tall).

[0086] Next, the theoretical formula for calculating the target gradient ac is explained. The target gradient ac is defined by equation (2). Furthermore, in Figure 10 In the diagram of the speed difference, equation (3) holds when the sum of the areas of right triangle A and rectangle B equals the cumulative phase difference from the arbitrary phase difference detection time td to the target completion time tall. The "10" on the right side of equation (3) represents the tooth pitch angle P (=10deg) of a gear with 36 teeth. The units of each parameter are as follows.

[0087] Rotational speed difference: ωd, ωs [deg / sec]; Time: Ts, Td, Tall [sec]; Gradient: ac[deg / sec 2 ]; Phase difference: Δθt, Δθd [deg].

[0088] [Formula 1] If Ts is eliminated from equations (2) and (3), then equation (4) is obtained to calculate ac.

[0089] [Formula 2] According to equation (4), the control device 7 calculates the target gradient ac based on the following six parameters. Additionally, the adjustment cycle number n is appropriately set. If these parameters can be obtained, the control device 7 does not need to predict the future engagement time at any phase difference detection moment td.

[0090] • Achieve target time Tall; • The time Td from the adjustment reference time t1 to the arbitrary phase difference detection time td; • The phase difference Δθd detected at any phase difference detection time td; • Target phase difference Δθt during engagement; • The rotational speed difference ωd at any phase difference detection time td; • Target speed difference ωs.

[0091] Among them, the target completion time Tall, the target phase difference Δθt at engagement, and the target rotational speed difference ωs are stored as predetermined values. However, referring to Figure 6 As described above, when a delay factor is generated in the operation of the clutch actuator 5, the target time correction unit 79 corrects the target time Tall based on the operation delay time estimated by the operation delay time estimation unit 78.

[0092] The control device 7 obtains information on the following three parameters at any phase difference detection time td.

[0093] • The time Td from the adjustment reference time t1 to the arbitrary phase difference detection time td; • The phase difference Δθd detected at any phase difference detection time td; • The rotational speed difference ωd at any phase difference detection time td.

[0094] The idea of ​​Equation (3) is as follows. The control device 7 calculates the target gradient ac such that "the time integral value of converting the rotational speed difference from any phase difference detection time td to the target time tall into the value of the phase difference change rate" is consistent with the phase difference obtained by adding "the difference between the target phase difference Δθt at engagement and the phase difference Δθd detected at any phase difference detection time td" to "an integer multiple of the tooth pitch angle of the first engagement tooth 13 and the second engagement tooth 14".

[0095] Reference Figure 11 The following flowchart illustrates the clutch engagement control of the first embodiment. In the flowchart description, the symbol "S" represents a step. To compare with the eighth embodiment... Figure 21 Shared step number, in Figure 11 The step numbers S15 to S17 are omitted.

[0096] After the synchronization operation begins, the speed difference gradually decreases. In S11, at the adjustment reference time t1, the speed difference ω0 is reached such that the phase difference sensor 6 can detect the phase difference. Afterwards, regarding the rotation of MG, S12 to S18 are executed. In S12, the control device 7 detects the phase difference Δθd at any phase difference detection time td. In the first embodiment, the initial engagement period after the adjustment reference time t1 is detected at any phase difference detection time td.

[0097] Control device 7 acquires information including the time Td from the adjustment reference time t1 to the arbitrary phase difference detection time td, the phase difference Δθd detected at the arbitrary phase difference detection time td, and the rotational speed difference ωd at the arbitrary phase difference detection time td. Additionally, control device 7 stores information about the completion target time Tall, the target phase difference Δθt, and the target rotational speed difference ωs. In S13, control device 7 begins phase difference adjustment based on this information.

[0098] In S14, control device 7 calculates the target gradient ac, changing it from the initial gradient a0 to the target gradient ac. In S18, at the arrival time ts after the target gradient duration Ts has passed from the arbitrary phase difference detection time td, the rotational speed difference reaches the target rotational speed difference ωs.

[0099] Following S11, actions S21-S23 concerning the clutch actuator 5 are executed in parallel with S12-S18. In S21, the control device 7 calculates the time tpre, which is a pre-action time Tpre ahead of the target completion time tall. In S22, the control device 7 begins the pre-action of the clutch actuator 5 at time tpre. In S23, at time tsb, the clutch actuator 5 reaches the standby position.

[0100] Following S18, which relates to MG rotation, and S23, which relates to ACT action, in S31, the target completion time Tall is elapsed from the adjustment reference time t1. In S32, the engagement of the interlocking clutch 10 is performed.

[0101] As described above, in the first embodiment, the control device 7 calculates the target gradient ac based on information obtained at any phase difference detection time td, changing it from the initial gradient a0 to the target gradient ac, thereby aligning the future first engagement time with the completion target time tall. This enables high-precision phase difference adjustment and improves the responsiveness of clutch engagement.

[0102] Here, for comparison, we assume other control methods. In this assumed control, after predicting the future engagement time, the engagement time is brought close to the arrival time. In this case, if torque is input to the input shaft to bring the engagement time close to the arrival time, the input shaft speed changes, causing the arrival time to deviate, and the accuracy of the phase difference adjustment may decrease. In contrast, in this embodiment, based on information obtained at any phase difference detection time td, the speed difference gradient is changed and the phase difference is adjusted simultaneously, thus achieving high-precision phase difference adjustment. Furthermore, in this embodiment, the future engagement time does not necessarily need to be predicted.

[0103] Next, as a variation different from the first embodiment, refer to Figures 12-17 The phase difference adjustment of the second to seventh embodiments will be explained in turn. Figures 12-17 Corresponding to the first embodiment Figure 10 Symbols for time, time difference, speed difference, gradient, phase difference, etc. Figure 10 The symbols in the diagram. A double-dotted line indicates a comparative control without phase difference adjustment. The diagram shows the ACT drive requirements and ACT stroke. Figure 10 They are the same, so they are omitted.

[0104] In any embodiment, the target phase difference Δθt at engagement is "Δθt = +5deg". Furthermore, except for the fourth embodiment, the phase difference Δθd detected at any phase difference detection time td is the phase difference at which the engaging clutch 10 can engage, i.e., "Δθt = +5deg". In this case, "Δθt - Δθd = 0". That is, except for the fourth embodiment, the engagement period is detected at any phase difference detection time td. Additionally, except for the third and fourth embodiments, the initial engagement period after the adjustment reference time t1 is detected at any phase difference detection time td.

[0105] (Second Implementation) exist Figure 12In the second embodiment shown, the number of adjustment cycles n is set to "n=2" to calculate the target gradient ac, so that the future second engagement period after any phase difference detection time td is consistent with the completion target time tall. In this way, the target gradient ac can also be calculated and changed from the initial gradient a0 to the target gradient ac, so that the future second and subsequent engagement periods are consistent with the completion target time tall.

[0106] (Third Implementation) exist Figure 13 In the third embodiment shown, the second engagement period after adjusting the reference time t1 is set to an arbitrary phase difference detection time td. Thus, the engagement periods after the second or subsequent engagements after adjusting the reference time t1 can also be set to arbitrary phase difference detection times td.

[0107] (Fourth Implementation) exist Figure 14 In the fourth embodiment shown, the phase difference Δθd detected at any phase difference detection time td is equivalent to the belly of the beat wave (refer to...). Figure 8 The phase difference becomes "Δθd=0". At this time, "n=1" and "Δθt-Δθd=+5deg". Thus, the phase difference Δθd detected at any phase difference detection time td can be any phase difference other than the phase difference that the engaging clutch 10 can engage.

[0108] (Fifth and Sixth Implementation Methods) exist Figure 15 , Figure 16 In the fifth and sixth embodiments shown, the control device 7, based on the information obtained at any phase difference detection time td, uses the "change characteristics of the input-output shaft speed difference" as a parameter. In addition to changing the gradient, it also changes the target speed difference from the reference value ωs to the changed value ωsc. The "information obtained by the control device at any phase difference detection time td" includes time Td, phase difference Δθd, and speed difference ωd, just like the calculation parameters for the target gradient ac.

[0109] exist Figure 15 , Figure 16 In the example shown, the modified target speed difference ωsc is set to a value smaller than the baseline value ωs (ωsc < ωs). The speed difference decreases along the target gradient ac to the modified target speed difference ωsc, thus arriving at time ts slightly later.

[0110] In the fifth embodiment, the target speed difference is restored to the reference value ωs before the target time tall is reached, and the engagement shock during engagement is managed at a standard level. In the sixth embodiment, the modified target speed difference ωsc is maintained until the target time tall is reached. Therefore, the engagement shock during engagement can be kept below the standard level.

[0111] (Seventh Implementation) exist Figure 17 In the seventh embodiment shown, the control device 7, based on the information obtained at any phase difference detection time td, as the "change characteristics of the input-output shaft speed difference", does not change the gradient, but changes the target speed difference from the reference value ωs to the changed value ωsc. The changed target speed difference ωsc is set to a value larger than the reference value ωs (ωsc>ωs).

[0112] Here, the reference value ωs for the target speed difference is set to a smaller value obtained by subtracting the tolerance (margin) from the allowable limit value ωs0 for engagement shock. Therefore, from the viewpoint of avoiding the effects of engagement shock, the target speed difference can be changed from the reference value ωs to a larger value ωsc within the tolerance (margin). By changing towards increasing the target speed difference, i.e., towards decreasing the input shaft speed Nin, the phase difference period is shortened, and the target completion time tall is advanced compared to the comparative example. Therefore, the responsiveness of clutch engagement can be improved.

[0113] (Eighth Implementation) Next, refer to Figures 18-21 The phase difference adjustment in the eighth embodiment will be explained. The means of phase difference adjustment includes a change in the target gradient ac. In the first to sixth embodiments described above, during the period from the adjustment reference time t1 to the arrival time ts, a phase difference Δθd for the purpose of phase difference adjustment is detected once at an arbitrary phase difference detection time td. During this period, for example, several phase difference detections for monitoring the phase difference may be performed, but at least one phase difference Δθd reflecting the phase difference adjustment is detected.

[0114] In contrast, in the eighth embodiment, it is based on the premise that multiple phase difference detections for the purpose of phase difference adjustment are performed at multiple arbitrary phase difference detection times during the period from the adjustment reference time t1 to the arrival time ts. Here, the case of detecting the phase difference Δθd1 to Δθd3 three times at three arbitrary phase difference detection times td1 to td3 will be described. In particular, in the eighth embodiment, it is preferable that the control device 7 predicts the future phase difference. In this case, Figure 6 The speed difference change characteristic calculation unit 74 obtains the phase difference estimated by the current phase difference estimation unit 73.

[0115] Figure 18 , Figure 19 , Figure 20 These are time diagrams showing the phase difference adjustment at arbitrary phase difference detection times td1, td2, and td3 during the first, second, and third engagement periods after the reference time t1. The first and second time diagrams represent provisional actions, while the third time diagram represents the final action. Similar to the diagrams in the above-described implementation, the double-dotted line indicates control in a comparative example where phase difference adjustment was not implemented.

[0116] like Figure 18 As shown, at the first arbitrary phase difference detection time td1, the first target gradient ac1 is calculated based on time Td1, phase difference Δθd1, and rotational speed difference ωd1, changing from the initial gradient a0 to the first target gradient ac1. At this point, it is assumed that the first target gradient ac1 is maintained until the arrival time ts, and the future action is temporarily predicted.

[0117] However, in control operations following any phase difference detection time td1, the actual phase difference may deviate from the target phase difference, depending on the control cycle, speed reading accuracy, and phase difference sensor reading accuracy. Alternatively, as shown by the dashed line, the actual speed difference may not change along the target gradient ac.

[0118] Therefore, at any phase difference detection moments td2 and td3 that become the second and third engagement detection opportunities, the control device 7 recalculates the target gradients ac2 and ac3, updating the previously calculated target gradients. Figure 19 , Figure 20 In the diagram, the dashed line represents the action calculated at the first arbitrary phase difference detection time td1.

[0119] like Figure 19 As shown, at the second arbitrary phase difference detection time td2, based on time Td2, phase difference Δθd2, and rotational speed difference ωd2, the second target gradient ac2 is calculated, updating the first target gradient ac1 (which was the previous value) to the second target gradient ac2 (which is the current value). At this time, for the detected phase difference Δθd2, the accuracy is improved by referring to the phase difference predicted at the previous arbitrary phase difference detection time td1. Figure 19 In the example, the target action based on the first target gradient ac1 deviates from the actual action, and the second target gradient ac2 calculated at the second arbitrary phase difference detection time td2 becomes a different value from the first target gradient ac1.

[0120] like Figure 20As shown, at the third arbitrary phase difference detection time td3, the third target gradient ac3 is calculated based on time Td3, phase difference Δθd3, and rotational speed difference ωd3, updating the second target gradient ac2 (which was the previous value) to the third target gradient ac3 (which is the current value). Similarly, for the detected phase difference Δθd3, the accuracy is improved by referring to the phase difference predicted at the previous arbitrary phase difference detection time td2. Figure 20 In the example, the target action based on the second target gradient ac2 is almost identical to the actual action. Therefore, the third target gradient ac3 calculated at the third arbitrary phase difference detection time td3 becomes approximately the same value as the second target gradient ac2.

[0121] The calculation formulas for the target gradients ac1 to ac3 at each arbitrary phase difference detection time td1 to td3 are expressed by equations (5.1) to (5.3). When an arbitrary phase difference detection time is set once per phase cycle after adjusting the reference time t1, the number of adjustment cycles n decreases by 1 for each phase difference detection. Figures 18-20 In the example, the first time is "n=4", the second time is "n=3", and the third time is "n=2". Additionally, in this example, the detected phase differences Δθd1, Δθd2, Δθd3, and the target phase difference Δθt are "Δθd1=Δθd2=Δθd3=Δθt=+5deg".

[0122] [Formula 3] Figure 21 A flowchart illustrating the clutch engagement control in the eighth embodiment. Figure 21 Compared to Figure 11 The loop steps S15~S17 have been added. S18 also serves as the loop termination check step. Other steps are the same as... Figure 11 They are essentially the same, with the same step numbers used but the explanations omitted. Furthermore, in S12, the symbol td is changed to td1, the symbol Δθd is changed to Δθd1, and in S14, the symbol ac is changed to ac1.

[0123] In S15, the phase difference Δθk is detected for the kth time (k≥2) at any phase difference detection time tdk. In S16, the control device 7 updates the target gradient ac(k-1) calculated at the previous arbitrary phase difference detection time td(k-1) to the target gradient ack calculated at the current arbitrary phase difference detection time tdk. Simultaneously, the future joining time is updated in S17.

[0124] In S18, it is determined whether the speed difference has reached the target speed difference ωs. If the result in S18 is "no", S15~S17 are repeated. If the result in S18 is "yes", the target gradient update ends and the process moves to S31. In S31, when the target time Tall is reached after the adjustment reference time t1, the engagement of the interlocking clutch 10 is performed in S32.

[0125] As described above, in the eighth embodiment, during the period from the adjustment reference time t1 to the arrival time ts, the target gradient ac1~ack is repeatedly updated based on feedback control of multiple phase difference detections, thereby enabling higher precision and more responsive clutch engagement.

[0126] (Other implementation methods) (a) Figure 1 , Figure 5 The example clutch is a planar gear structure in which the clutch components 11 and 12 move relative to each other axially, and the first engagement tooth 13 of the first clutch component 11 and the second engagement tooth 14 of the second clutch component 12 can directly mesh. In addition to this structure, a sleeve-type clutch can also be used, in which the clutch components are stationary and the sleeve, which acts as a relay component, is provided by other components.

[0127] A sleeve-type clutch, for example, is disclosed in Japanese Patent Application Publication No. 2010-96190. In this sleeve-type clutch, the first engagement tooth of the first clutch component and the second engagement tooth of the second clutch component can engage via a sleeve acting as a relay component. The sleeve is axially moved relative to the first and second clutch components by a clutch actuator, thereby switching the engagement and disengagement states of the clutch. The detection portion of the phase difference sensor is adjusted to output different sensor signals in the engagement and disengagement states.

[0128] (b) Not limited to Figure 1 The illustrated vehicle 90, which is capable of switching between 2WD and 4WD, has a structure in which the engagement clutch 10 is located between the rear wheel MG82 and the rear wheel 92. For example, the engagement clutch 10 can also be located between the front wheel MG and the front wheel in a front-wheel drive (FF) vehicle.

[0129] (c) The phase difference sensor 6 is not limited to, for example, Figure 5 , Figure 7As illustrated, the total area of ​​the engaging teeth 13 and 14 within the detection range SA can be detected as long as information related to the difference in rotational position between the input shaft 3 and the output shaft 4 can be detected and converted into a phase difference. Alternatively, the phase difference can be defined as 0 when the first clutch component 11 and the second clutch component 12 are engaged. In this case, the phase difference of the 36-tooth engagement clutch 10 varies in the range of 0 to +10 degrees. Regardless of the definition of the phase difference, the relative value of "Δθt-Δθd" in equation (4) is the same.

[0130] (d) The rotary drive source connected to the input shaft 3 is not limited to the MG82, but can also be an internal combustion engine, etc. In addition, the engagement control system of the interlocking clutch can also be applied to the power transmission mechanism of general machinery, in addition to the power transmission system of a vehicle.

[0131] (e) Synchronization actions are not limited to actions where the output shaft speed Nout (i.e., vehicle speed) is constant and only the input shaft speed Nin gradually increases; they can also be actions where the output shaft speed Nout and the input shaft speed Nin change in a way that approaches each other.

[0132] (f) in Figure 9 In the synchronization operation shown, input shaft 3 stops in the released state. After the control device 7 receives the engagement instruction, the input shaft speed Nin increases from 0 rpm towards the target speed N_tgt. Conversely, the input shaft speed Nin can also be maintained at a predetermined target idle speed in the released state. For example, the higher the vehicle speed, the higher the target idle speed can be set, thereby shortening the synchronization operation time at high speeds.

[0133] In addition, Figure 2 In vehicles, there are situations such as [1] rain, snow, frozen roads, [2] sharp turns, [3] red lights ahead, and braking at the very end of a traffic jam, where a rapid switch from 2WD to 4WD is required. Therefore, by setting a higher target idle speed in these situations, the synchronization time can be shortened. However, conversely, due to the deterioration of power consumption, it is preferable not to set the target idle speed too high, but to set an appropriate target idle speed based on the vehicle's operating conditions.

[0134] The present disclosure is not limited to such implementation, but can be implemented in various ways without departing from its spirit.

[0135] (The disclosure of technical ideas) This specification discloses several technical ideas described in the following list of items. Some items are sometimes described by selectively referencing a prior item in a multiple dependent form in a subsequent item. Furthermore, some items may be described by referring to another multiple dependent form of an item with a multiple dependent form. Items described in these multiple dependent forms define several technical ideas.

[0136] (Technical Idea 1) A clutch engagement control system, comprising: The interlocking clutch (10) has a first clutch component (11) and a second clutch component (12). The first clutch component is connected to the input shaft (3) and has a plurality of first engagement teeth (13) arranged circumferentially. The second clutch component is connected to the output shaft (4) and has a plurality of second engagement teeth (14) arranged circumferentially that can directly or via a relay component engage with the first engagement teeth. The interlocking clutch switches the engagement state and the release state of the first clutch component and the second clutch component. Clutch actuator (5) causes the first clutch component and the second clutch component to move relative to each other in the axial direction, or, when the relay component is used, causes the relay component to move relative to the first clutch component and the second clutch component in the axial direction; Phase difference sensor (6) detects the phase difference between the first clutch component and the second clutch component; and The control device (7) controls the difference between the rotational speed of the input shaft and the rotational speed of the output shaft, i.e., the input-output shaft speed difference. Based on the engagement instruction to engage the clutch in the released state, it performs a synchronization operation to gradually reduce the input-output shaft speed difference until it reaches the target speed difference (ωs) that allows the clutch to engage. Regarding the engagement period of the phase difference that allows the clutch to engage during this synchronization operation, the control device (7) detects the current engagement period based on the output of the phase difference sensor, and outputs a drive instruction to the clutch actuator in such a way that the clutch engages at a future engagement period after the input-output shaft speed difference reaches the target speed difference. After the input-output shaft speed difference reaches the adjustment reference time (t1) at which the phase difference sensor can detect the phase difference (ω0), the control device, based on information obtained at any phase difference detection time (td) that detects any phase difference according to the output of the phase difference sensor, changes the change characteristics of the input-output shaft speed difference to adjust the phase difference between the first clutch component and the second clutch component, so that any future engagement period is consistent with the completion target time (tall), which is the time after the adjustment reference time has elapsed for the completion target time (Tall).

[0137] (Technical Idea 2) According to the engagement control system of the interlocking clutch described in Technical Concept 1, when the time change rate of the input-output shaft speed difference is defined as the gradient, and the gradient during the period from the adjustment reference time to the arbitrary phase difference detection time is set as the initial gradient (a0), The control device calculates the target value of the gradient, i.e. the target gradient (ac), based on the information obtained at the arbitrary phase difference detection time, and changes the initial gradient to the target gradient.

[0138] (Technical Idea 3) According to the engagement control system of the interlocking clutch described in Technical Concept 2, the control device calculates the target gradient based on the completion target time (Tall), the time from the adjustment reference time to the arbitrary phase difference detection time (Td), the phase difference detected at the arbitrary phase difference detection time (Δθd), the target phase difference at engagement (Δθt), the input and output shaft speed difference at the arbitrary phase difference detection time (ωd), and the target speed difference (ωs).

[0139] (Technical Idea 4) According to the engagement control system of the interlocking clutch described in technical concept 3, the control device calculates the target gradient such that the time integral value of the value obtained by converting the input and output shaft speed difference during the period from the arbitrary phase difference detection time to the completion of the target time is consistent with the phase difference obtained by adding an integer multiple of the tooth pitch angle of the first engagement tooth and the second engagement tooth to the difference between the target phase difference (Δθt) at engagement and the phase difference (Δθd) detected at the arbitrary phase difference detection time.

[0140] (Technical Idea 5) According to any one of the technical concepts 1 to 4, in the engagement control system of the interlocking clutch, the phase difference detected at the arbitrary phase difference detection time is the phase difference at which the interlocking clutch can engage.

[0141] (Technical Idea 6) According to any one of technical concepts 1 to 5, in the engagement control system of the interlocking clutch, the control device changes the target speed difference based on information obtained at the arbitrary phase difference detection time.

[0142] (Technical Idea 7) According to any one of technical concepts 1 to 6, in the engagement control system of the interlocking clutch, the control device initiates the pre-action of the clutch actuator at a predetermined pre-action time (Tpre) earlier than the target completion time. In the event of a delay factor in the operation of the clutch actuator, the target completion time is corrected based on the operation delay time.

[0143] (Technical Idea 8) According to any one of the technical concepts 2 to 4, the engagement control system for the interlocking clutch is based on the premise that multiple phase difference detections are performed at multiple arbitrary phase difference detection times (td1 to td3) during the period from the adjustment reference time to the time when the input-output shaft speed difference reaches the target speed difference (ts). The control device will update the target gradient calculated at the previous arbitrary phase difference detection time to the target gradient calculated at the current arbitrary phase difference detection time.

[0144] The control device and method described in this disclosure can also be implemented using a dedicated computer, which is provided by comprising a processor and memory programmed to perform one or more functions embodied in a computer program. Alternatively, the control device and method described in this disclosure can also be implemented using a dedicated computer provided by a processor composed of one or more dedicated hardware logic circuits. Alternatively, the control device and method described in this disclosure can also be implemented using one or more dedicated computers composed of a combination of a processor and memory programmed to perform one or more functions and a processor composed of one or more hardware logic circuits. Furthermore, the computer program can also be stored as instructions to be executed by the computer on a computer-readable non-transferable tangible recording medium.

[0145] This disclosure is described based on embodiments. However, this disclosure is not limited to these embodiments and structures. This disclosure also includes various modifications and equivalent variations. In addition, various combinations and methods, and further, other combinations and methods that include only one element, or more than or less than the elements, also fall within the scope and spirit of this disclosure.

Claims

1. A clutch engagement control system, have: The interlocking clutch (10) has a first clutch component (11) and a second clutch component (12). The first clutch component is connected to the input shaft (3) and has a plurality of first engagement teeth (13) arranged circumferentially. The second clutch component is connected to the output shaft (4) and has a plurality of second engagement teeth (14) arranged circumferentially that can directly or via a relay component engage with the first engagement teeth. The interlocking clutch switches the engagement state and the release state of the first clutch component and the second clutch component. Clutch actuator (5) causes the first clutch component and the second clutch component to move relative to each other in the axial direction, or, when the relay component is used, causes the relay component to move relative to the first clutch component and the second clutch component in the axial direction; Phase difference sensor (6) detects the phase difference between the first clutch component and the second clutch component; and The control device (7) controls the difference between the rotational speed of the input shaft and the rotational speed of the output shaft, i.e., the input-output shaft speed difference. Based on the engagement instruction to engage the engaged clutch in the released state, it performs a synchronization operation to gradually reduce the input-output shaft speed difference to reach a target speed difference (ωs) that enables the engaged clutch to engage. Regarding the engagement period of the phase difference that enables the engaged clutch to engage during this synchronization operation, the control device detects the current engagement period based on the output of the phase difference sensor, and outputs a drive instruction to the clutch actuator in a manner that engages the engaged clutch at a future engagement period after the input-output shaft speed difference reaches the target speed difference. After the input-output shaft speed difference reaches an adjustment reference time (t1) at which the phase difference can be detected by the phase difference sensor, the control device, based on information obtained at any phase difference detection time (td) that detects any phase difference according to the output of the phase difference sensor, changes the change characteristics of the input-output shaft speed difference to adjust the phase difference between the first clutch component and the second clutch component, so that any future engagement period is consistent with the completion target time (tall), which is the time after the completion target time (Tall) from the adjustment reference time.

2. The engagement control system for the interlocking clutch as described in claim 1, When the time-varying rate of change of the input-output shaft speed difference is defined as the gradient, and the gradient during the period from the adjustment reference time to the arbitrary phase difference detection time is set as the initial gradient (a0), The control device calculates the target value of the gradient, i.e. the target gradient (ac), based on the information obtained at the arbitrary phase difference detection time, and changes the initial gradient to the target gradient.

3. The engagement control system for the interlocking clutch as described in claim 2, The control device calculates the target gradient based on the target completion time (Tall), the time from the adjustment reference time to the arbitrary phase difference detection time (Td), the phase difference detected at the arbitrary phase difference detection time (Δθd), the target phase difference at engagement (Δθt), the input and output shaft speed difference at the arbitrary phase difference detection time (ωd), and the target speed difference (ωs).

4. The engagement control system for the interlocking clutch as described in claim 3, The control device calculates the target gradient such that the time integral of the value obtained by converting the input / output shaft speed difference during the period from the arbitrary phase difference detection time to the completion of the target time is consistent with the following phase difference: the phase difference is obtained by adding an integer multiple of the tooth pitch angle of the first engagement tooth and the second engagement tooth to the difference between the target phase difference (Δθt) at engagement and the phase difference (Δθd) detected at the arbitrary phase difference detection time.

5. The engagement control system for the interlocking clutch as described in claim 1 or 2, The phase difference detected at any given phase difference detection time is the phase difference at which the engagement clutch can engage.

6. The engagement control system for a clutch as described in claim 1 or 2, The control device changes the target rotational speed difference based on information obtained at the arbitrary phase difference detection time.

7. The engagement control system for the interlocking clutch as described in claim 1, The control device initiates the pre-action of the clutch actuator at a predetermined pre-action time (Tpre) (tpre) earlier than the target completion time. In the event of a delay factor in the operation of the clutch actuator, the target completion time is corrected based on the operation delay time.

8. The engagement control system for the interlocking clutch as described in claim 2, Based on the premise of performing multiple phase difference detections at multiple arbitrary phase difference detection times (td1~td3) during the period from the adjustment reference time to the time (ts) when the input-output shaft speed difference reaches the target speed difference, The control device will update the target gradient calculated at the previous arbitrary phase difference detection time to the target gradient calculated at the current arbitrary phase difference detection time.

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