Method for determining synchronization point of engagement process of dog clutch

Abstract

The invention relates to a method for determining a synchronization point Psact during an engagement process of a dog clutch (1), in which an electric machine (2) can be drivingly connected to a component to be driven via the dog clutch (1), the dog clutch (1) having at least one first clutch element (1a) and an axially movable second clutch element (1b), the electric machine (2) being adjusted in rotational speed, the axial movement of the second clutch element (1b) of the dog clutch (1) is divided into at least two control phases V1, V2, i.e. A first control phase V1 and a second control phase V2, by determining the average torque M1av and the maximum torque M1max of the electric machine (2) during the first control phase V1, and by determining the maximum torque M1max of the electric machine (2) during the second control phase V1, the axial movement of the second clutch element (1b) of the dog clutch (1) is determined to set a predetermined rotational speed difference between the two clutch elements (1a), (1b), and wherein the axial movement of the second clutch element (1b) of the dog clutch (1) is divided into at least two control phases V1, V2, i.e. A first control phase V1 and a second control phase V2. And generating a first criterion for detecting a temporary synchronization point Pspre by comparing the torque value M1av, M1max determined in the first control phase V1 with the torque M2 determined in the second control phase V2, and generating a second criterion for determining the temporary synchronization point Pspre as an actual synchronization point Psact, by comparing the torque value M1av, M1max determined in the first control phase V1 with the torque M2 determined in the second control phase V2.

Description

Technical Field

[0001] The present invention relates to a method for determining a synchronization point during the engagement process of a claw clutch, wherein a motor can be effectively driven connected to a component to be driven via the claw clutch, wherein the claw clutch has at least one first clutch element and an axially movable second clutch element, and wherein the motor is speed-controlled to set a predetermined speed difference between the two clutch elements.

[0002] Furthermore, the present invention relates to the application of a method according to the present invention in electric or hybrid motor vehicles. Background Technology

[0003] In electric and hybrid vehicles, a so-called claw clutch is typically used to transmit the rotational motion or torque of the electric motor to the driven axle of the vehicle via a transmission. A claw clutch has two clutch elements: a first clutch element is effectively connected, for example, to the electric motor drive, and a second clutch element is effectively connected to the drive of the axle to be driven in the vehicle. To allow the claw clutch to engage with low wear and low noise while the vehicle is in motion, the two claw elements need to be synchronized in speed. In electric and hybrid vehicles, this speed synchronization is typically achieved actively by the electric motor by establishing a defined speed difference between the clutch elements of the claw clutch. That is, to engage the claw clutch, the electric motor is controlled by a control device to create a nearly constant speed difference band between the electric motor and the axle to be driven in the vehicle.

[0004] The "synchronization point" of a claw clutch is the point in time at which the two clutch elements of the claw clutch first make contact during the engagement or disengagement process, either through frictional or form-fit. Therefore, for the aforementioned application of claw clutches in electric or hybrid vehicles, the synchronization point represents the point in time from which the driving motor effectively connects to the axle of the vehicle to be driven.

[0005] By accurately understanding the synchronization point of the clutch elements in a claw clutch, several advantages are derived, which improve shift comfort, shift time, and NVH (noise, vibration, and harshness) during the shifting process. N oise V ibration H It has a positive effect on arshness (noise, vibration and acoustic roughness). Summary of the Invention

[0006] The object of this invention is to provide a method for simply and accurately determining the synchronization point during the engagement process of a claw clutch, via which an effective driving connection can be established between a motor and a component to be driven.

[0007] Furthermore, the object of this invention is to propose an advantageous application of the method according to the invention.

[0008] The aforementioned needs can be met by the subject matter of the invention according to independent claims 1 and 3. Advantageous embodiments of the invention are described in the dependent claims.

[0009] The method according to the invention is used to determine the synchronization point during the engagement process of a claw clutch, wherein a motor can be effectively connected to the driven component via the claw clutch.

[0010] According to the present invention, the claw clutch has at least one first clutch element and a second clutch element that is axially movable.

[0011] According to the invention, the motor is speed controlled, thereby setting a predetermined speed difference between the two clutch elements.

[0012] According to the present invention, the axial movement of the second clutch element of the claw clutch is divided into at least two adjustment stages, namely a first adjustment stage and a second adjustment stage.

[0013] According to the present invention, a first standard is generated to determine a temporary synchronization point by determining the average torque and maximum torque of the motor during a first adjustment phase, and by comparing the torque value determined in the first adjustment phase with the torque detected in a second adjustment phase, and a second standard is generated to determine the temporary synchronization point as the actual synchronization point.

[0014] The method according to the invention, when the engagement requirement of a claw clutch is required, preferably includes at least the following steps:

[0015] - A predetermined speed difference is set between the two clutch elements of the claw clutch via a motor.

[0016] - Calculate the average torque of the motor during the first adjustment phase of the second clutch element of the claw clutch.

[0017] - Determine the maximum torque of the motor during the first adjustment phase of the claw clutch.

[0018] - The average torque and the determined maximum torque of the temporary motor are calculated during the first adjustment phase of the claw clutch.

[0019] - Detect the torque of the motor during the second adjustment phase of the claw clutch, and simultaneously compare the detected torque with the maximum torque determined in the first adjustment phase.

[0020] - When the maximum torque determined in the first adjustment phase is first exceeded during the second adjustment phase, the timing point and the position of the second clutch element are temporarily stored as a synchronization point.

[0021] - In the second adjustment phase, the average torque is calculated starting from the detected temporary synchronization point.

[0022] - The average torque calculated in the second adjustment phase, starting from the detected temporary synchronization point, will be compared with the average torque calculated and temporarily stored in the first adjustment phase.

[0023] - When the average torque calculated from the detected temporary synchronization point in the second adjustment phase is higher than the average torque calculated in the first adjustment phase by a predetermined amount, the temporary synchronization point is saved as the actual synchronization point.

[0024] According to the present invention, the method of the present invention is applied to electric motor vehicles or hybrid motor vehicles.

[0025] By employing the method according to the invention for determining the synchronization point during the engagement process of a claw clutch effectively connected to a motor drive, improved NHV and vibration characteristics can be achieved in addition to reducing the shift time of the claw clutch. Furthermore, by accurately determining the synchronization point of the claw clutch, wear on the clutch elements of the claw clutch can be reduced.

[0026] Driving safety can be improved by applying the method according to the invention to electric or hybrid vehicles, particularly in the field of electric vehicle axle devices. Attached Figure Description

[0027] The invention is described below by way of example with reference to the accompanying drawings.

[0028] Figure 1 A schematic, detailed diagram of a motor vehicle drive system with an electric motor and a transmission with a disengaged claw clutch is shown.

[0029] Figure 2 According to Figure 1 The structure shows a graph of parameters used to determine the synchronization point of a claw clutch. Detailed Implementation

[0030] exist Figure 1 The details of the motor vehicle drive system, namely the gear transmission 3 and the motor 2, are schematically and exemplary shown in the diagram. Figure 1The topology shown describes the method according to the invention; however, the method can also be used for other transmission topologies, such as planetary gear transmissions.

[0031] The motor 2 is effectively driven and connected to the input shaft 4 of the gear transmission device 3. Furthermore, the motor 2 is connected to an inverter 9 for energizing the motor 2. The inverter 9 has a control unit 10. The purpose of the control unit 10 is to send a preset target speed value to the inverter 9. Subsequently, the inverter 9 independently adjusts the motor 2 to the required speed.

[0032] The gear transmission device 3 can have multiple gear stages; however, in Figure 1 Only one gear stage 5 is shown in the diagram, which has a fixed gear 5a and a movable gear 5b. Both the fixed gear 5a and the movable gear 5b are spur gears. The fixed gear 5a is mounted on the input shaft 4 of the gear transmission 3. The movable gear 5b is mounted on the output shaft 6 of the gear transmission 3.

[0033] A driven gear 7 is also provided on the output shaft 6 of the gear transmission device. The driven gear is effectively connected to the axle (not shown) of the motor vehicle, or more precisely, to the differential (not shown) located at the axle.

[0034] The movable wheel 5b can be engaged with the output shaft 6 of the gear transmission device 3 in a torsion-resistant manner by means of the claw clutch 1.

[0035] The claw clutch 1 has a first clutch element 1a, i.e., a claw element, and a second clutch element 1b, i.e., a sliding sleeve, which is axially movable. In the following description, the reference numeral "1a" is used to refer to the claw element as the first clutch element 1a. Similarly, the reference numeral "1b" is used to refer to the sliding sleeve as the second clutch element 1b.

[0036] The claw element 1a is torsionally and axially fixed to the movable wheel 5b. The sliding sleeve 1b can be translated toward the claw element 1a and is torsionally connected to the output shaft 6 of the gear transmission device 3.

[0037] Therefore, by engaging the sliding sleeve 1b into the claw element 1a, the movable wheel 5b can be torsionally connected to the output shaft 6 of the gear transmission 3 to achieve power transmission from the motor 2 to the output shaft 6 of the gear transmission 3 via the gear stage 5, wherein the fixed wheel 5a is torsionally held on the input shaft 4 of the gear transmission 3.

[0038] In order to remove the sliding sleeve 1b from... Figure 1The disengaged position shown in the diagram transitions to the engaged position, i.e., the engagement process is performed, and the sliding sleeve 1b is effectively driven into connection with the actuator unit 8. The actuator unit 8 currently includes a shift drum (not shown in detail).

[0039] By rotating the shift drum of actuator unit 8, the sliding sleeve 1b can move toward the claw element 1a so that the sliding sleeve 1b engages with the claw element 1a (engagement process). Similarly, by rotating the shift drum of actuator unit 8, the sliding sleeve 1b can disengage from the claw element 1a (disengagement process).

[0040] For this purpose, the sliding sleeve 1b has a guide element that is guided in the shift groove of the shift drum so as to convert the rotation of the shift drum into a translational movement (not shown) of the guide element together with the sliding sleeve 1b.

[0041] The following will be based on Figure 2 Describes the method for determining the synchronization point P_s of the claw clutch 1 according to the present invention. act The method.

[0042] Figure 2 Chart I shows the position P of the shift drum of actuator unit 8, plotted in degrees [°] over time t in seconds [s], with respect to the shift drum rotating around its own axis.

[0043] Figure 2 Chart II shows the torque variation curve M of motor 2 as the speed of motor 2 is adjusted, plotted in Newton-meters [Nm] and time t in seconds [s].

[0044] The engagement process between the sliding sleeve 1b and the claw element 1a of the claw clutch 1 begins at time point t_0 and ends at time point t_end. Therefore, according to Figure 2 The diagram illustrates how the sliding sleeve 1b starts from the beginning position P_0 at time point t_0, i.e., from the disengaged state of the pawl clutch 1, and moves until it reaches the end position P_end at time point t_end, i.e., the engaged state of the pawl clutch 1.

[0045] The first adjustment phase V1 begins at time t_1 and ends at time t_2.

[0046] During the first adjustment phase V1 of the sliding sleeve 1b, the sliding sleeve 1b is not expected to contact the claw element 1a. The first adjustment phase V1 can also be referred to as the "unreliable synchronization region" of the sliding sleeve 1b.

[0047] During the first adjustment phase V1, a preset speed difference is established between the movable wheel 5b and the output shaft 6 to be synchronized. The movable wheel 5b is mounted on the output shaft and engages with the motor 2 via a fixed wheel 5a mounted on the input shaft 4 to set the speed of the movable wheel 5b. The preset speed difference between the movable wheel 5b and the output shaft 6 to be synchronized also implies a preset speed difference between the sliding sleeve 1b and the claw element 1a of the claw clutch 1, wherein the sliding sleeve is torsionally engaged with the output shaft 6, and the claw element is torsionally held at the movable wheel 5b.

[0048] During the first adjustment phase V1, the sliding sleeve 1b moves from the starting position P_0 to the first position P_1. The first position P_1 is a defined intermediate position of the sliding sleeve 1b before it contacts the claw element 1a of the movable wheel 5b.

[0049] The sliding sleeve 1b of the claw clutch 1 moves from the starting position P_0 to the first position P_1 by means of the adjusted shift drum of the actuator unit 8 toward the claw element 1a of the movable wheel 5b.

[0050] During the first adjustment phase V1, the torque M1 during the first adjustment phase is detected. Furthermore, during the first adjustment phase V1, the average torque M1_av during the first adjustment phase V1 is calculated, and the maximum torque M1_max during the first adjustment phase V1 is determined. When the first adjustment phase V1 is successfully completed without an abort criterion, for example, when the desired speed difference between the sliding sleeve 1b and the claw element 1a is not set, the calculated value of the average torque M1_av during the first adjustment phase V1 and the determined value of the maximum torque M1_max during the first adjustment phase V1 are temporarily stored in the storage unit of the control unit 10.

[0051] The second adjustment phase V2 proceeds after the first adjustment phase V1. The second adjustment phase V2 begins at time point t_2 and ends at time point t_3.

[0052] During the second adjustment phase V2, the sliding sleeve 1b is expected to come into contact with the claw element 1a. The second adjustment phase V2 can also be referred to as the "reliable synchronization region" of the sliding sleeve 1b.

[0053] During the second adjustment phase V2, the sliding sleeve moves from the first position P_1 to the second position P_2. The second position P_2 is another intermediate position of the sliding sleeve 1b after the sliding sleeve 1b engages with the claw element 1a of the movable wheel 5b.

[0054] The sliding sleeve 1b of the claw clutch 1 moves from the first position P_1 to the second position P_2 by means of the adjusted shift drum of the actuator unit 8 toward the claw element 1a of the movable wheel 5b.

[0055] During the second adjustment phase V2, the torque M2 during the second adjustment phase is detected, and the detected torque M2 is compared with the maximum torque M1_max detected in the first adjustment phase V1.

[0056] Once the detected torque exceeds the maximum torque M1_max in the first adjustment phase V1 for the first time during the second adjustment phase V2, the position P_s of the sliding sleeve 1b at time point t_s is temporarily stored as a temporary synchronization point P_s. pre Subsequently, the average torque M2_av is calculated from time point t_s until the end of the second adjustment phase V2, i.e., until time point t_3. If the average torque M2_av calculated during the time period from time point t_s to time point t_3 is higher than the average torque M1_av calculated in the first adjustment region V1 by a certain amount, then the previously stored position P_s at time point t_s is stored as the actual synchronization point P_s. act .

[0057] After the second adjustment phase V2, the sliding sleeve 1b is fully engaged with the claw element 1a during the time period from t_3 to t_end.

[0058] List of reference numerals

[0059] 1-claw clutch

[0060] 1a First clutch element (claw element)

[0061] 1b Second clutch element (sliding sleeve)

[0062] 2 motors

[0063] 3 Gear Transmission Device

[0064] 4 input axes

[0065] 5 gear stages

[0066] 5a Fixed Wheel

[0067] 5b active wheel

[0068] 6 input axes

[0069] 7 Driven gear

[0070] 8 actuator units

[0071] 9 inverters

[0072] 10 control units

[0073] V1 First Adjustment Phase

[0074] V2 Second Adjustment Phase

[0075] M1_av Average torque during the first adjustment phase

[0076] M2_av Average torque during the second adjustment phase

[0077] M1_max is the maximum torque during the first adjustment phase.

[0078] The torque of M1 during the first adjustment phase

[0079] M2 torque during the second adjustment phase

[0080] P_s pre Temporary synchronization point

[0081] P_s act Actual synchronization point

[0082] t time

[0083] t_s synchronization point time point

[0084] t_0 start time point

[0085] t_end end time point

[0086] t_1, t_2, t_3 (intermediate) time points

[0087] Position P (of the sliding sleeve)

[0088] Location of P_s synchronization point

[0089] P_0 starting position

[0090] P_end end position

[0091] P_1 First Position

[0092] P_2 Second Position

Claims

1. A method for determining the synchronization point P_s during the engagement process of a claw clutch 1. act The method involves a motor 2 capable of effectively connecting as a drive component to a driven component via a claw clutch 1, wherein the claw clutch 1 has at least one first clutch element 1a and a second clutch element 1b capable of axial movement, wherein the motor 2 is speed-regulated to set a predetermined speed difference between the two clutch elements 1a and 1b, and wherein the axial movement of the second clutch element 1b of the claw clutch 1 is divided into at least two adjustment phases V1 and V2, namely a first adjustment phase V1 and a second adjustment phase V2, wherein a first criterion is generated by determining the average torque M1_av and the maximum torque M1_max of the motor 2 during the first adjustment phase V1, and by comparing the torque values ​​M1_av and M1_max determined in the first adjustment phase V1 with the torque M2 determined in the second adjustment phase V2, in order to detect a temporary synchronization point P_s. pre And generate a second standard so as to set the temporary synchronization point P_s pre The actual synchronization point P_s is determined. act .

2. The method according to claim 1, Its features are, The method, when the engagement requirement of the claw clutch 1 is met, includes at least the following steps: - A predetermined speed difference is set between the two clutch elements 1a and 1b of the claw clutch 1 via the motor 2. - Calculate the average torque M1_av of the motor 2 during the first adjustment phase V1 of the second clutch element 1b of the claw clutch 1. - Determine the maximum torque M1_max of the motor 2 during the first adjustment phase V1 of the second clutch element 1b of the claw clutch 1. - Temporarily store the average torque M1_av calculated and the maximum torque M1_max determined by the motor 2 in the first adjustment stage V1 of the second clutch element 1b of the claw clutch 1. - Detect the torque M2 of the motor 2 during the second adjustment phase V2 of the second clutch element 1b of the claw clutch 1, and simultaneously compare the detected torque with the maximum torque M1_max determined in the first adjustment phase V1. - When the maximum torque M1_max determined in the first adjustment phase V1 is first exceeded in the second adjustment phase V2, the time point t_s and the position P_s of the second clutch element 1b are temporarily stored as a temporary synchronization point P_s. pre , - In the second adjustment phase V2, from the detected temporary synchronization point P_s pre Start calculating the average torque M2_av, - In the second adjustment phase V2, from the detected temporary synchronization point P_s pre The initially calculated average torque M2_av is compared with the average torque M1_av calculated and temporarily stored in the first adjustment phase V1. - When in the second adjustment phase V2, from the detected temporary synchronization point P_s pre When the initially calculated average torque M2_av is higher than the average torque M1_av calculated in the first adjustment phase V1, the temporary synchronization point P_s is adjusted. pre Save as the actual synchronization point P_s act .

3. The application of the method according to claim 1 or 2 in an electric motor vehicle or a hybrid motor vehicle.

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