Method for commissioning pump having pump motor arranged in hydraulic system

Abstract

The invention relates to a method for detecting the correct direction of rotation of a pump (100) of a hydraulic system of an actuator in a motor vehicle, the hydraulic system having: a first switchable valve (300) actuated by means of energization; and a pump (100) having a pump motor (1000) and activated by means of energization; and a control device controlling the first switchable valve (300) and the pump (100), in which the pump (100) delivers fluid in a first rotational direction to the pressure line (700) and in a second rotational direction to the reservoir (900), in which the pressure line (700) has a pressure sensor (600) and is hydraulically connected to the first switchable valve (300), characterized in that the pressure sensor (600) is hydraulically connected to the pressure line (700) and the reservoir (900) is hydraulically connected to the first switchable valve (300). In order to determine the direction of rotation of the pump (100), the pump motor (1000) is energized in sequence in two different directions of rotation, and the pressure at the pressure sensor (600) is determined in each case, and the direction of rotation of the pump (100) is deduced therefrom.

Description

Technical Field

[0001] The invention relates to a method having the features of the preamble of claim 1 . Background Art

[0002] The scope of application of the present invention is:

[0003] In addition to the electric drive motor, many projects now include a hydraulic system in the system. The hydraulic system is used to cool the electric drive motor, to actuate a clutch in a so-called disconnect coupling unit and, if necessary, to actuate a parking lock, as described, for example, in the unpublished German patent application DE 10 2022 113 487.3.

[0004] The pump motor drives the pump. The hydraulic oil delivered by the pump is therefore available to the high-pressure system for operating the actuators. In the high-pressure path, a pressure sensor is installed after the pump and the valve, via which the discharge can be controlled. During the commissioning routine, the pump is rotated and it is checked according to the prior art, for example via the rotor position sensor of the motor, whether the correct direction of rotation can be controlled.

[0005] According to the prior art, a hydraulic system with an electrically driven reversing pump is known. In this regard, one direction of rotation of the reversing pump can be assigned a volume flow function, such as a cooling function, and the other direction of rotation of the reversing pump can be assigned an actuation function, such as the actuation of a clutch and / or a parking lock. Such a hydraulic system and a method for operating such a hydraulic system are known from, for example, public documents DE 10 2018 112 663 A1, DE 10 2018 112 665 A1, DE 10 2018 113 316 A1 and DE 10 2018 114 789 A1. Other hydraulic systems are known from public documents DE 10 2016 213 318 A1 and WO 2012 / 113 368 A1, etc.

[0006] However, to ensure the correct rotation direction of the pump, a rotor position sensor or resolver is definitely required. Summary of the invention

[0007] The invention is based on the object that for cost reasons, pumps in such hydraulic systems should be controlled without sensors. This means that a rotor position sensor is no longer necessary. In this case, it is no longer possible to check the direction of rotation via a resolver.

[0008] This object is achieved by a method having the features according to claim 1 .

[0009] According to the method of the present invention for detecting the correct rotation direction of a pump of a hydraulic system of an actuator in a motor vehicle, the hydraulic system comprises: a first switchable valve actuated by means of electrical activation; and a pump having a pump motor and actuated by means of electrical activation; and a control device, which controls the first switchable valve and the pump, wherein the pump delivers fluid to a pressure line in a first rotation direction and to a reservoir in a second direction, wherein the pressure line has a pressure sensor and is hydraulically connected to the first switchable valve, and it can be provided that, in order to determine the rotation direction of the pump, the pump motor is energized in two different rotation directions in turn, and the pressure at the pressure sensor is determined in each case, and the rotation direction of the pump is inferred therefrom.

[0010] In a particularly preferred embodiment of the invention, it can be provided that the correct direction of rotation is present if the pressure determined at the pressure sensor is higher in the first direction of rotation than in the second direction of rotation.

[0011] In another particularly preferred embodiment of the present invention, it can be provided that the hydraulic system of the actuator has a second switchable valve, which is also actuated by means of power supply, and the control device also controls the second switchable valve, and wherein the pressure pipeline is also hydraulically connected to the second switchable valve.

[0012] In a particularly preferred embodiment of the invention, the first switchable valve is a 2 / 2-way valve.

[0013] In a particularly preferred embodiment of the invention, the second switchable valve is a 4 / 2-way valve.

[0014] In a particularly preferred embodiment of the invention, it can be provided that the first switchable valve is hydraulically connected to a cooling line for cooling a drive motor of the motor vehicle.

[0015] In a particularly preferred embodiment of the invention, it can be provided that the second switchable valve is hydraulically connected to a clutch actuator for actuating the clutch.

[0016] In a particularly preferred embodiment of the invention, it can be provided that the first switchable valve is closed when the pump is actuated in the first rotational direction and in the second rotational direction.

[0017] In a particularly preferred embodiment of the invention, it can be provided that, when the pump is actuated in the first rotational direction and in the second rotational direction, the second switchable valve is switched in such a direction that the clutch piston moves into the clutch actuator in the direction of the nearest stop in the clutch cylinder.

[0018] In a particularly preferred embodiment of the invention, it can be provided that the pump is actuated in such a way that the clutch piston does not move into the clutch actuator when the pump is actuated in the first rotational direction and in the second rotational direction.

[0019] The method according to the invention thus has the advantage that there is no need to reconnect the phase connections, since the commissioning routine according to the invention stores in the non-volatile memory of the control what current results in the desired forward rotation of the pump. In addition, there is no need to color code the phase connection cables or to maintain the correct sequence of the phase connections (poles), since the commissioning routine can determine the correct energization for the life of the control. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Further advantages and advantageous embodiments of the invention are the subject matter of the following figures and description of the invention.

[0021] In detail, in the accompanying drawings:

[0022] Figure 1 The hydraulic design of the hydraulic system is shown.

[0023] Figure 2 The method for debugging according to the present invention is shown. Figure 1 A flow chart of a method for providing a hydraulic pump in a hydraulic system. DETAILED DESCRIPTION

[0024] During commissioning according to the invention, the pressure measured by pressure sensor 600 in pressure line 700 of the high-pressure part of the hydraulic system is now taken into account instead of the rotor position sensor which is no longer present.

[0025] For considerations in the commissioning routine according to the invention, the system pressure control valve 300, i.e. the 2 / 2-way valve, also referred to below as the first switchable valve 300, in the high-pressure part of the hydraulic system must be controlled so that an increased pressure can be built up. This can be done by closing the system pressure control valve 300 in method step 1100.

[0026] In addition, before or at the beginning of actuation of the pump 100, the clutch actuator 400, more precisely the clutch piston 450, can be moved to one of the two stops in the cylinder of the clutch actuator 400 by means of the second switchable valve 200, a 4 / 2-way valve, so that once this state is reached, it is no longer possible to prevent or reduce the pressure buildup by mechanically increasing the hydraulic volume. According to the invention, since the piston position in the cylinder is generally always known, the second switchable valve 200 is actuated accordingly to move to the closer stop, since it is not necessary to consider during commissioning whether the clutch is thereby opened or closed.

[0027] Alternatively, the actuation of the pump 100 may be performed only with limited intensity and not too abruptly, so that the clutch piston 450 does not move significantly within the clutch actuator 400 due to friction and braking within the clutch actuator 400, so that the clutch piston 450 does not approach either of the two stops in the clutch cylinder. This still results in a sufficiently meaningful pressure build-up at the pressure sensor 600.

[0028] If the electric motor 1000 of the pump 100 rotates in the desired forward direction in method step 1200, then the pressure in the pressure line 700 of the high-pressure section must increase significantly, since the system pressure control valve 300 is controlled at a correspondingly high level. Here, for example, a pressure of about 8 bar is to be expected. The measured pressure of the pressure sensor 600 can be easily evaluated.

[0029] If the electric motor 1000 rotates in the wrong direction, no pressure increase will occur and the pressure on the actual high-pressure side in the pressure line 700 will even decrease, since the high-pressure side becomes the suction side if the direction of rotation is incorrect.

[0030] In this case, the commissioning routine must store the appropriate values ​​in the non-volatile memory of the control unit for later use. During subsequent use, the stored correction values ​​must be used; the motor will then always turn in the correct direction. Test procedures such as Figure 2 shown.

[0031] For plausibility purposes, in particular after the expected current supply in method step 1200 has resulted in the desired forward rotation, the current supply is then reversed in method step 1300 and a check is made as to whether the pressure sensor 600 indicates a sufficient drop in pressure in this direction of rotation.

[0032] The commissioning procedure can easily be repeated later, for example in a workshop.

[0033] For example, if a loss of non-volatile memory is displayed, repetition may also be considered during operation of the vehicle. By executing this routine, the system may enter a drivable state, thereby achieving limp home. The system may inform the driver of the abnormal waiting time via a message display.

[0034] There are further advantages for production. Since the order of the phase connections due to mandatory testing during commissioning no longer plays a role, there is no need to color-code the phase connection cables. Therefore, rejections due to opposite colors are impossible.

[0035] Having a standard mark in one color can also clarify possible misallocations during nailing, if necessary, especially when working with suppliers. In addition, cost advantages may come from higher order quantities of one color.

[0036] Variants are also conceivable, such as performing a one-sided high-voltage test in method step 1200 and then not performing method step 1300 in order to shorten the process. If a rotor position sensor is present in the system, another possibility is to use the rotor position sensor for a plausibility check.

[0037] Reference numerals list

[0038] 50 Filters

[0039] 100 Pumps

[0040] 200 Second switchable valve (clutch)

[0041] 300 First switchable valve (cooling)

[0042] 400 Clutch Actuator

[0043] 450 Clutch Piston

[0044] 500 Cooling Line

[0045] 600 Pressure Sensor

[0046] 700 Pressure Line

[0047] 800 Enter the pipeline

[0048] 900 Storage

[0049] 1000 Pump Motor

[0050] 1100 Methods and Steps

[0051] 1200 Methods and Steps

[0052] 1300 Methods and Steps

[0053] 1400 Methods and Steps

[0054] 1500 Method steps.

Claims

1. A method for detecting the correct rotation direction of a pump (100) of a hydraulic system of an actuator in a motor vehicle, the hydraulic system having: a first switchable valve (300) actuated by means of energization; and the pump (100) having a pump motor (1000) and actuated by means of energization; and a control device, the control device controlling the first switchable valve (300) and the pump (100), wherein: The pump (100) delivers fluid into a pressure line (700) in a first rotational direction and into a reservoir (900) in a second direction, wherein the pressure line (700) has a pressure sensor (600) and is hydraulically connected to the first switchable valve (300), characterized in that, in order to determine the rotational direction of the pump (100), the pump motor (1000) is energized in two different rotational directions in sequence and in each case the pressure at the pressure sensor (600) is determined and the rotational direction of the pump (100) is inferred therefrom.

2. The method according to claim 1, characterized in that The correct direction of rotation is present in case the pressure determined at the pressure sensor (600) is higher in the first direction of rotation than in the second direction of rotation.

3. The method according to any one of claims 1 or 2, characterized in that The hydraulic system of the actuator has a second switchable valve (200), which is also actuated by means of energization, and the control device also controls the second switchable valve (200), and wherein the pressure line (700) is also hydraulically connected to the second switchable valve (200).

4. The method according to any one of claims 1 to 3, characterized in that The first switchable valve (300) is a 2 / 2-way valve.

5. The method according to any one of claims 3 to 4, characterized in that The second switchable valve (200) is a 4 / 2-way valve.

6. The method according to any one of claims 1 to 5, characterized in that The first switchable valve (300) is hydraulically connected to a cooling line (500) for cooling a drive motor of the motor vehicle.

7. The method according to any one of claims 3 to 6, characterized in that The second switchable valve (200) is hydraulically connected to a clutch actuator (400) for actuating a clutch.

8. The method according to any one of the preceding claims, characterized in that When the pump (100) is actuated in the first rotational direction and in the second rotational direction, the first switchable valve (300) is closed.

9. The method according to any one of claims 7 to 8, characterized in that When the pump (100) is actuated in the first and second rotational directions, the second switchable valve (200) is actuated so that the clutch piston (450) moves into the clutch actuator (400) in the direction of the nearest stop in the clutch cylinder.

10. The method according to any one of the preceding claims 7 to 9, characterized in that When the pump (100) is actuated in the first rotational direction and the second rotational direction, the pump (100) is actuated such that a clutch piston (450) does not move into the clutch actuator (400).

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