Method for operating a motor vehicle and controller
By coupling the mass to the shaft before the parking lock disengages to increase the moment of inertia, the problem of damage to power transmission components when the parking lock disengages is solved, thus achieving protection of the power transmission system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHAFA FRIEDRICH SCHAFFEN CO LTD
- Filing Date
- 2022-02-21
- Publication Date
- 2026-07-03
AI Technical Summary
In the prior art, the parking lock may cause damage to the powertrain components when it disengages, especially when the parking lock engages on a slope, the sudden release of load causes the powertrain components to accelerate.
Before the parking lock disengages, the coupling mass is coupled to the still-locked shaft, increasing the moment of inertia on the shaft to reduce angular velocity and rotational acceleration, thereby reducing the load on the powertrain components.
By increasing the moment of inertia, the risk of damage to powertrain components when the parking lock disengages is reduced, thus protecting the structural components of the powertrain.
Smart Images
Figure CN114962635B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a method for operating a motor vehicle. Furthermore, this invention also relates to a controller for implementing this method. Background Technology
[0002] As is known in practice, a parking lock prevents a motor vehicle from rolling away undesirably while it is stationary. Here, the parking lock provides a mechanical lock to the motor vehicle's powertrain. This mechanical lock locks the shaft coupled to the vehicle's output unit and thus inhibits rotation of the shaft and the output unit, thereby locking the motor vehicle to prevent it from rolling away.
[0003] Parking locks typically have a parking lock pawl and a parking lock wheel. The parking lock pawl works in conjunction with the parking lock wheel to mechanically lock the power transmission system, such that when the parking lock pawl engages with the parking lock wheel, which is connected to a shaft coupled to the vehicle's output unit, the parking lock engages and the shaft and thus the output unit are locked.
[0004] Parking locks typically include a parking lock actuator, a parking lock locking mechanism, and a parking lock sensor. The parking lock actuator actuates the parking lock pawl to engage or disengage the parking lock. The parking lock locking mechanism locks and unlocks the parking lock actuator. The parking lock pawl cannot be actuated when the parking lock actuator is locked via the parking lock locking mechanism. The parking lock sensor detects the status of the parking lock.
[0005] Parking locks for motor vehicles are disclosed in DE 10 2009 004 263 B4 and DE 10 2017 211 025 A1. Parking locks for motor vehicles are also known from EP 0 823 359 B1 and DE 10 2018 202 370 A.
[0006] DE 102 55 714 A1 discloses a method for operating a motor vehicle, specifically a method for controlling an automatic transmission having multiple switching elements and a parking lock. When the parking lock is activated, the output is locked via at least one friction-locked switching element of the transmission to secure it; after the parking lock is deactivated, the switching element is controlled to disconnect.
[0007] Then, when the vehicle is locked on a slope using the parking lock to prevent it from rolling away, a high load is applied to the parking lock. This load can suddenly accelerate the powertrain components when the parking lock is disengaged. The entire load held by the parking lock when it is engaged causes the structural components or parts of the powertrain to accelerate when the parking lock is disengaged. This may damage the structural components or parts of the powertrain.
[0008] There is a need to reduce the risk of damage to powertrain components when the parking lock is disengaged. Summary of the Invention
[0009] Therefore, the purpose of this invention is to create a novel method and controller for operating motor vehicles.
[0010] The objective is achieved by a method for operating a motor vehicle, which has a drive unit, an output unit, and a parking lock, wherein the parking lock locks a shaft coupled to the output unit in an engaged state and releases the shaft in a disengaged state.
[0011] According to the present invention, the method includes: coupling at least one coupling mass to a still locked shaft coupled to an output section while increasing the moment of inertia acting on the shaft; and disengaging the parking lock after the at least one coupling mass is coupled to the shaft.
[0012] Using the present invention, in order to disengage the parking lock, it is preferable to couple at least one coupling mass to the still locked shaft before disengaging the parking lock, while increasing the moment of inertia acting on the shaft.
[0013] By increasing the moment of inertia acting on the output-side shaft, the angular velocity and rotational acceleration when the parking lock is disengaged can be reduced. This reduction in angular velocity and rotational acceleration reduces the load on the components of the powertrain, more specifically, those coupled to the output-side shaft. This, in turn, reduces the risk of damage to such components of the powertrain when the parking lock is disengaged.
[0014] According to an advantageous further improvement of the invention, the load acting on or related to the parking lock before disengagement is calculated. Then, if the calculated load is greater than a boundary value, the at least one coupling mass is coupled to the still-locked shaft before disengagement, simultaneously increasing the moment of inertia acting on the shaft. This further improvement of the invention calculates the load acting on the parking lock before disengagement. The at least one coupling mass is then coupled to the shaft only if the load is greater than a boundary value. Conversely, if the load is less than the boundary value, this is not necessary.
[0015] Preferably, the at least one coupling mass, which is coupled to the still-locked shaft before the parking lock is disengaged, is determined based on the magnitude of the load acting on the parking lock before disengagement. This allows the coupling mass to be determined and coupled to the shaft as required.
[0016] Preferably, the load acting on the parking lock before disengagement is calculated based on the mass of the vehicle and the slope of the lane in which the vehicle is located. Calculating the load acting on the parking lock before disengagement based on the mass of the vehicle and the slope of the lane in which the vehicle is located is feasible in a simple and reliable manner.
[0017] A controller for operating a motor vehicle according to the present invention is defined as follows: the motor vehicle has a drive unit, an output unit, and a parking lock, wherein the parking lock, in an engaged state, locks a shaft coupled to the output unit and in a disengaged state, releases the shaft, characterized in that: the controller is configured to: manipulate at least one structural component to couple at least one coupling mass to the still locked shaft coupled to the output unit, while increasing the moment of inertia acting on the shaft; and disengage the parking lock after the at least one coupling mass is coupled to the shaft. Attached Figure Description
[0018] Preferred further improvements are derived from the dependent claims and the following description. Embodiments of the invention are described in more detail with reference to the accompanying drawings, but are not limited thereto. Hereinafter:
[0019] Figure 1 A schematic diagram of the powertrain of a motor vehicle is shown.
[0020] Figure 2 A timeline is shown to illustrate the invention.
[0021] Figure 3 A schematic diagram of another powertrain system for a motor vehicle with an exemplary transmission is shown;
[0022] Figure 4 Show Figure 3 The shift matrix of the transmission. Detailed Implementation
[0023] Figure 1 A schematic diagram of a motor vehicle's powertrain is shown, including a drive unit 1 and an output unit 2. The drive unit 1 may be an internal combustion engine, a hybrid drive unit, or an electric motor.
[0024] Figure 1 A shaft 3 coupled to the output unit 2 and a parking lock 4 are also shown. When the parking lock 4 is engaged for mechanical locking and thus for locking the vehicle to prevent unwanted rollover, the parking lock 4 locks the shaft 3 coupled to the output unit 2. Here, a mass 5 related to the configuration of the powertrain acts on the locked shaft 3.
[0025] In particular, when the vehicle is on a slope with the parking lock 4 engaged, a relatively high load is applied to the parking lock 4. This load is applied to the previously locked shaft 3 and released after the parking lock 4 is disengaged, resulting in a relatively large rotational acceleration of the previously locked shaft 3. Figure 2 The time t indicates the time history 8 of the angular velocity formed on the previously locked shaft 3 when the parking lock 4 is disengaged. When the angular velocity and rotational acceleration on shaft 3 are high, the components of the powertrain coupled to shaft 3 may be damaged.
[0026] It is recommended that, in order to disengage the parking lock 4, or more precisely, before disengaging the parking lock 4, the coupling mass 6 be coupled to the still-locked shaft 3, while simultaneously increasing the moment of inertia acting on shaft 3. Therefore, Figure 1 A switching element 7 is shown connected between shaft 3 and coupling mass 6. When the switching element 7 is open, it disconnects coupling mass 6 from shaft 3, and when the switching element 7 is closed, it couples coupling mass 6 to shaft 3.
[0027] Specifically, the load acting on the parking lock 4 before it is disengaged should be calculated. This load can be calculated based on the mass of the vehicle and the gradient of the lane in which the vehicle is located.
[0028] When the calculated load exceeds the boundary value, the coupling mass 6 is coupled to the still-locked shaft 3 via the closing switching element 7 before the parking lock 4 is disengaged. This increases the moment of inertia acting on shaft 3, thereby reducing the angular velocity and rotational acceleration on the now-released shaft 3 when the parking lock 4 is subsequently disengaged.
[0029] When the calculated load is less than the boundary value, the coupling mass 6 is not coupled to the shaft 3 before the parking lock 4 is disengaged.
[0030] Figure 2 Curve history 9 illustrates the angular velocity time history that can be achieved using the present invention by coupling the coupling mass 6 to the shaft 3. Compared to curve history 8, the angular velocity and rotational acceleration are reduced. Therefore, the risk of damage to the powertrain can be reduced.
[0031] The present invention can be used to determine the magnitude of the coupling mass coupled to the shaft 3 before the parking lock 4 is disengaged, based on the magnitude of the load acting on the parking lock 4 before disengagement.
[0032] Therefore, before disengaging the parking lock 4, the corresponding portion of the coupling mass can be coupled to the locked shaft 3 as required via the corresponding switching element, so as to couple the coupling mass to be optimally matched with the load size.
[0033] Figure 1 The parking lock 4, masses 5 and 6, and switching element 7 can be components of the transmission 10, which is coupled between the drive unit 1 and the output unit 2, and when a gear is engaged in the transmission 10, the transmission couples the drive unit 1 to the output unit 2.
[0034] Figure 3 An exemplary configuration of a transmission 10 having multiple gear sets 11, 12, 13 and 14 and multiple switching elements 15, 16, 17, 18 and 19 is shown, wherein switching elements 15 and 16 are friction-locked brakes A and B, and switching elements 17, 18 and 19 are friction-locked clutches C, D and E.
[0035] Figure 4 Show Figure 3 The shift matrix of the transmission 10, where, from Figure 3 It can be concluded that the transmission 10 can provide a total of eight force-locking forward gears and one force-locking reverse gear. In each of these traction-transmitting gears, a defined first number of switching elements, i.e., three switching elements, are closed, while a defined second number of switching elements, i.e., two switching elements, are always open in each traction-transmitting and therefore force-locking gear.
[0036] Those switching elements that close in the corresponding gear that transmits traction force. Figure 4 The dot marks indicate this. Therefore, in forward gear 1, switching elements A, B, and C are closed; in forward gear 2, switching elements A, B, and E are closed; and in reverse gear R, switching elements A, B, and D are closed.
[0037] exist Figure 3 The example also shows a hydraulic starting element coupled between the drive unit 1 and the transmission 10, wherein the hydraulic starting element has a torque converter 20 and a torque converter bridging clutch 23 connected in parallel with the torque converter.
[0038] The turbine 21 and pump 22 of the torque converter 20 are shown. The pump 22 is coupled to the drive unit 1, while the turbine 21 is coupled to the transmission 10.
[0039] If in Figure 3 The motor vehicle shown in the diagram passes through Figure 3 The parking lock 4 (not shown) is locked on the slope to prevent it from rolling away, so when the drive unit 1 is running... Figure 3 The switching elements 15 and 16, i.e., brakes A and B, are at least partially closed, especially up to the so-called engagement point. Then, when the load acting on the shaft 3 before disengaging the parking lock 4 exceeds the boundary value, in Figure 3 By closing, especially the switching element 16, i.e., the clutch B, an additional mass, i.e., the coupling mass 6, can be coupled to the shaft 3, thereby increasing the moment of inertia acting on the shaft 3. If the locking of the shaft 3 is then released by disengaging the parking lock 4, the angular velocity and rotational acceleration on the now-released shaft 3 decrease, thereby reducing the load on such components of the power transmission coupled to the shaft 3.
[0040] Therefore, in Figure 3 The coupling mass can be connected to shaft 3 by closing brake B. If transmission 10 is locked, for example by closing switching elements 15, 16, and 17 and another switching element, this coupling mass can be increased. The corresponding coupling mass is determined, in particular, by the structural components of the transmission and thus by its mass.
[0041] As a coupling mass 6, the mass of the motor or other components of the power transmission system can also be connected to the shaft 3 locked by the parking lock 4 before disengaging the parking lock 4.
[0042] The present invention also relates to a controller for operating a motor vehicle, the controller being configured to implement the above-described method on the control side.
[0043] The controller is preferably a transmission controller that provides open-loop and / or closed-loop control of the operation of the transmission 10. The transmission controller is not shown in the figure.
[0044] The controller according to the invention controls at least one structural component to couple the at least one coupling mass 6 to the locked shaft 3 before disengaging the parking lock 4 and increasing the moment of inertia acting on the shaft 3.
[0045] In this regard, the controller determines the load that acts on the parking lock 3 before the parking lock 4 is disengaged. The controller preferably calculates this load based on the mass of the vehicle and the gradient of the lane in which the vehicle is located.
[0046] The controller determines, based on the calculated load magnitude, the at least one coupling mass 6 coupled to the shaft 3 and the at least one structural component 7 to be operated for this purpose before disengaging the parking lock 4.
[0047] Depending on the load magnitude, the controller manipulates at least one structural component 7 to couple at least one coupling mass 6 to the still-locked shaft 3 before disengaging the parking lock 4. Disengaging the parking lock 4 releases the previously locked shaft 3.
[0048] Figure Labels
[0049] 1. Drive unit
[0050] 2 Output Section
[0051] 3-axis
[0052] 4. Parking lock
[0053] 5. Quality
[0054] 6. Coupling quality
[0055] 7 Switching Components
[0056] 8. Angular velocity history
[0057] 9. Angular velocity history
[0058] 10. Transmission
[0059] 11 Gear Set
[0060] 12 Gear Sets
[0061] 13 Gear Set
[0062] 14 Gear Set
[0063] 15 Switching element A
[0064] 16 Switching element B
[0065] 17 Switching element C
[0066] 18 Switching element D
[0067] 19 Switching element E
[0068] 20 Torque Converter
[0069] 21 Turbo
[0070] 22 pumps
[0071] 23 Torque converter bridging clutch
Claims
1. A method for operating a motor vehicle, the motor vehicle having a drive unit (1), an output unit (2), and a parking lock (4). The parking lock (4) locks the shaft (3) coupled to the output section (2) when engaged, and releases the shaft (3) when disengaged. characterized in that The method includes: At least one coupling mass (6) is coupled to the still locked shaft (3) coupled to the output section (2), while increasing the moment of inertia acting on the shaft (3); and After the at least one coupling mass (6) is coupled to the shaft (3), the parking lock (4) is disengaged.
2. The method according to claim 1, characterized in that: Calculate the loads or related loads that act on the parking lock (4) before it is disengaged; Then, when the calculated load is greater than the boundary value, the at least one coupling mass (6) is coupled to the locked shaft (3) before disengaging the parking lock (4).
3. The method of claim 2, wherein: The at least one coupling mass (6) coupled to the shaft (3) before disengaging the parking lock (4) is determined based on the calculated load magnitude.
4. The method according to claim 2 or 3, characterized in that: The load is calculated based on the mass of the motor vehicle and the slope of the lane in which the motor vehicle is located.
5. The method according to any one of claims 1 to 3, characterized in that: The motor vehicle has a transmission (10) connected between the drive unit (1) and the output unit (2) and has a plurality of switching elements (15, 16, 17, 18, 19) for coupling the at least one coupling mass (6) to the shaft (3) by closing at least one switching element of the transmission (10).
6. A controller for operating a motor vehicle, the motor vehicle having a drive unit (1), an output unit (2), and a parking lock (4). in, The parking lock (4) locks the shaft (3) coupled to the output section (2) when engaged, and releases the shaft (3) when disengaged. The controller is characterized in that it is configured to: Manipulate at least one structural component (7) to couple at least one coupling mass (6) to a still locked shaft (3) coupled to the output section (2), while increasing the moment of inertia acting on the shaft (3); and After the at least one coupling mass (6) is coupled to the shaft (3), the parking lock (4) is disengaged.
7. The controller according to claim 6, characterized in that: The controller calculates the loads or related loads that act on the parking lock before it is disengaged (4); Then, when the load is greater than the boundary value, the controller manipulates the at least one structural component (7) before disengaging the parking lock (4) to couple the at least one coupling mass (6) to the locked shaft (3).
8. The controller according to claim 6, characterized in that: The controller determines, based on the calculated load magnitude, the at least one coupling mass (6) coupled to the shaft (3) before disengaging the parking lock (4) and determines the at least one structural component (7) to be manipulated for this purpose.
9. The controller according to claim 7 or 8, characterized in that: The controller calculates the load based on the mass of the vehicle and the slope of the lane in which the vehicle is located.
10. The controller according to any one of claims 6 to 8, characterized in that: The motor vehicle has a transmission (10) connected between a drive unit (1) and an output unit (2) and has a plurality of switching elements (15, 16, 17, 18, 19), and the controller operates at least one switching element of the transmission (10) to close in order to couple at least one coupling mass.