JP3078887U - Start / drive unit for internal combustion engines in motor vehicles - Google Patents

Abstract

(57) [Problem] To provide a start / drive unit that is suitable for operation with a large number of start cycles, operates with low noise, and sufficiently satisfies the energy demand, with only one electric device without a normal starter. Make improvements to be able to respond. Each starting method is preceded by a start clearing phase, in which the crankshaft of the internal combustion engine is rotated by an electric device under the connection of a clutch. The starting characteristics are detected using the numbers and a determination is made as to the subsequent operating phases (direct start phase, positioning phase, pre-injection phase, impulse start phase) and their starting parameters are determined.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 SUMMARY OF THE INVENTION The present invention is a start / drive unit for an internal combustion engine in a motor vehicle having at least two starting methods, comprising a crankshaft and a clutch between the internal combustion engine and a vehicle transmission, and further comprising a clutch. The invention relates to a start / drive unit for an internal combustion engine in a motor vehicle, having an electrical device connected to the internal combustion engine via the same.

[0002]

[Prior art]

 In this type of start / drive unit for two starting methods, the selection of the starting method is dependent on the temperature of the internal combustion engine. For these starting methods, two starting systems are required. Electrical equipment used as motors and generators is used to start a warm engine. In the case of a cold engine, on the other hand, a normal starter is used for starting with this electrical equipment. These two starting systems are costly to be able to operate in start / stop operating mode and active commercial operating mode.

[0003] Conventional starters have several disadvantages for various reasons. In terms of starter motor downtime, pinion and gear rim life, clutch overhaul and increased noise, this type of starter requires a limited number of start cycles, e.g. start / stop operating modes for each traffic light, traffic congestion or overrun. The goal cannot be achieved if there is an increase with rapid and low-noise starting requirements based on repeated starting with a hot engine after the phase. Even if the starter is equipped with more sophisticated electronics (which leads to an increased number of start cycles), it is not enough to achieve the required number of start cycles of 200,000 or more . With such advanced starting systems, the desired starting times and low noise cannot be achieved.

In the application of the starter generator for impulse start, the starter generator is additionally connected via a starting clutch between the crankshaft and the flywheel, or the flywheel and the vehicle transmission It is connected to the crankshaft instead of the normal clutch in between and acts as follows. That is, the electric motor first rotates the flywheel mass at a high speed up to the driving speed (for example, 1000 revolutions per minute) under the dissociation of the internal combustion engine (and the speed changer), and then quickly connects the starting mass. The internal combustion engine is actuated via the rotational energy under the clutch or the clutch. Such an impulse start is suitable for a normal cold start, but for repeated starts after the end of a traffic light or overrun phase under a warm engine. Uneconomical because of the time required.

[0005]

[Problems to be solved by the invention]

 An object of the present invention is to provide a starting / driving unit of the type described at the beginning, which is suitable for operation with a large number of starting cycles and operates with low noise, using only one electric device without a normal starter, and The goal is to make improvements to meet the energy needs.

[0006]

[Means for Solving the Problems]

 According to the present invention, the above problem is solved in that each starting method is preceded by a starting clarification phase, in which the crankshaft of the internal combustion engine is rotated by an electric device under the connection of a clutch. The starting characteristic is detected by the control unit using the rotational speed, the subsequent operating phases (direct start phase, positioning phase, pre-injection phase, impulse start phase) are determined and the starting parameters are determined. Is done.

[0007]

[Embodiment of the invention]

 In the starting clarification phase, the current starting characteristic is detected under the engagement of the clutch, and a subsequent operating phase is selected on the basis of the current starting characteristic and the starting parameters for it are determined. A starting generator is preferably used as the electrical device.

A simple detection of the current starting characteristic is achieved by: That is, in the start clarification phase, it is achieved by detecting whether the guidance value is revered by the crankshaft via a speed sensor, and deriving the starting method and starting parameters from the detected value. As the rotation speed elapses, the drag torque existing at the time of starting appears. When the drag torque is large, the internal combustion engine is cold, and when the drag torque is small, the internal combustion engine is already warm. It is possible to determine the starting method selectively via temperature measurement, or to carry out a validity check accordingly. Normally, the speed profile is already detected via the crankshaft speed sensor, so that it is also applicable to the derivation of the current starting characteristic. The appropriate starting mode is identified in each case via a predetermined limit value of the measured drag torque.

[0009] The apparent difference in the course of the rotational speed is caused by the following, depending on the configuration. That is, a decision on the starting method results from being derivable from the first and / or second maximum speed and / or the range of the speed profile between the first and / or second minimum speed. From the result, a unique inference to the current drag torque can be derived, and it can be used for selecting an appropriate starting method.

When the drag torque is large, it is selected as the operation phase of the impulse start. Under drag torques that are too high and high compared to a normal impulse start, a so-called dry impulse start phase, ie a start phase without ignition and injection, is introduced before the impulse start phase. In this case, synchronization and possibly fuel pre-injection are performed using the engine electronic control unit (Motronic). This is a precedent impulse start, in which the flywheel is first spun to the required speed by the starting generator with the clutch disengaged in order to obtain position identification / synchronization by connecting the clutch. .

[0011] The electrical equipment may be configured with or without a sub-gear transmission, which may be directly connected to the transmission shaft or may include a rapidly connected starting clutch. It may be connected to the internal combustion engine via the power supply.

[0012]

【Example】

 Next, the present invention will be described in detail in the following specification with reference to the drawings.

As shown in FIG. 1, the vehicle transmission FG is connected to the internal combustion engine VM via an intermediary transmission ZG and a clutch K used as a starting clutch. The electric equipment used as the starting generator S / G is directly connected to the transmission shaft, and is connected to the internal combustion engine VM via the flywheel SR and the clutch K. The rotational speed sensors DG1 and DG2 already provided for other functions detect the passage of the rotational speeds on the input and output sides of the clutch K in the electric start control device STG, from which the start clarification is made. In the phase, a decision is made on the relevant starting method and the starting parameters for it are determined.

[0014] In contrast to the solution described above, a cold start with a relatively low rotational torque of the electrical equipment is performed by a start clarification phase prior to the impulse start. In this case, the clutch K is connected under the first starting method and the crankshaft KW is positioned by the dry impulse start under the second starting method, or the crankshaft / camshaft position is completely identified. You. Thereby, in some cases, the pre-injection can be stopped in the next fired cylinder. The subsequent impulse start is started reliably and very quickly, even for otto motors. As is well known, preliminary injection and ignition are performed via the engine control device MSG. This controller is synchronized with the start controller STG.

The start / drive unit according to the invention provides an optimal combination of synchronized impulse start in extremely cold start regions and direct start to relatively low temperature limits. In this case, the temperature decreases over the course of the rotational speed. In the second starting mode, a precisely adjusted impulse start occurs. As a result, a minimum start-up time and a high start-up dynamic characteristic are achieved with the internal combustion engine VM warmed to the operating temperature.

Under the cold start limit temperature, the torque of the starting generator S / G required for (impulse) starting of the first starting method is smaller by a factor of 2 than in the case of a corresponding direct starting. (Up to a factor of 4 under the second starting method).

A further significant improvement is achieved with a virtually uninterrupted speed-controlled starting sequence. No additional sensors are required to determine the starting method and the selection of the starting parameters. This is because the existing crankshaft speed sensor DG1 can be used for this.

There is no need to identify the inertial operation of the internal combustion engine or position it in a pendulum operation. Therefore, the means for checking the crankshaft position under the stopped internal combustion engine can be omitted.

Depending on the center-of-gravity goals of the vehicle concept, the two starting methods are positioned as particularly advantageous as follows.

Starting method 1 : (target setting is a small battery output) * Phase 1 (starting clutch K connection) The crankshaft KW is rotated at a predetermined voltage or output by using the starting generator S / G. Accompanying detection of starting characteristics using drag torque measurements. The decision on the starting method is based on a comparison with predetermined limits. In addition, starting parameters, for example starting speed and starting time, are detected (start clarification phase).

* Phase 2A (start clutch K connection) Direct-coupling start when engine drag torque of phase 1 is small (start when warm) * Phase 2B (start clutch K connection) When phase 1 drag torque is large Positioning, angle identification, and possibly preliminary injection.

* Phase 3B (start clutch K disengagement) Rotation start of the flywheel SR by the start generator.

* Phase 4B (Starting Clutch K Connection) Quick synchronized impulse start (cold start).

Phases 1 and 2A or phases 1 and 2B are portions where the direct start is crossed or before the subsequent impulse start.

Start method 2: (Target setting is starting generator current) * Phase 1 (start clutch K connection) Rotation of crankshaft KS using starting generator S / G. Detection of start characteristics, determination of start method, determination of start parameters (start clarification phase) * Phase 2A (clutch K connection) Direct start (corresponding to phase 2A of start method 1) = Start in warm condition.

* Phase 2B (clutch K connection) Impulse start (corresponding to phases 2B to 4B of start method 1) = start in cold state.

* Phase 2C (clutch K disengagement) The flywheel SR is started and rotated to a low number by the starting generator S / G.

* Phase 3C (clutch K connection) Dry impulse start with positioning and angle identification and possibly preliminary injection.

* Phase 4C (clutch C disengagement) The rotation start of the flywheel SR with the consumption controlled rotation start period / start rotation speed.

* Phase 5C (clutch K connection) "Synchronized" rapid impulse start = cold start at extremely low temperatures.

The starting process is generally performed with the following functions under the control of the rotational speed.

The moment of the flywheel SR alone or the rotation speed of the flywheel SR with the internal combustion engine VM is measured. The crankshaft / camshaft-rotation angle is detected. The starting characteristics are detected and the starting parameters are determined. Automatic switching according to demand for direct connection start to impulse start accompanied by rotation start Under dry impulse start, the flywheel SR is selectively started to rotate by the start generator S / G, and immediately after the clutch is connected. It is also possible that the synchronization and the pre-injection take place, after which the residual energy of the flywheel SR performs an impulse start.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

[Explanation of symbols]

 VM Internal combustion engine DG Speed sensor SR Flywheel K Clutch FG Vehicle transmission KW Crankshaft STG Start control device

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[Procedure amendment]

[Submission date] February 7, 2001 (2001.2.7)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims for utility model registration

[Correction method] Change

[Correction contents]

[Utility model registration claims]

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Manfred Ackermann Germany Oppenweiler Mittelgasse 3

Claims (8)

[Utility model registration claims] 1. A starting / driving unit for an internal combustion engine in a motor vehicle having at least two starting methods, comprising:
In the type having a clutch between the crankshaft and the internal combustion engine and the vehicle transmission, and further having an electric device connected to the internal combustion engine via the clutch, each starting method clarifies the starting method. Prior to the starting phase, in the starting clarification phase, the crankshaft (KW) of the internal combustion engine (VM) is rotated by electrical equipment under the connection of the clutch (K), with the starting control (STG) A starting characteristic is detected using the rotational speed, a determination is made regarding subsequent operating phases (direct start phase, positioning phase, pre-injection phase, impulse start phase), and the starting parameters are determined. A starting / driving unit for an internal combustion engine in a motor vehicle, characterized in that: 2. A starting generator (S) as said electrical equipment.
The starting / driving unit according to claim 1, wherein / G) is used. 3. A starting control device (STG) detects a rotation speed of a crankshaft (KW) via a rotation speed sensor (DG1) in a start clearing phase, and derives a starting method and starting parameters therefrom. A starting / driving unit according to claim 1. 4. The starting / driving unit according to claim 3, wherein the rotational speed curve can be picked up by an existing crankshaft rotational speed sensor (DG1). 5. The method according to claim 3, wherein the determination on the starting method is derivable from a region of the speed profile between the first and / or second maximum speed and / or the first and / or second minimum speed. Or the starting / driving unit according to 4. 6. An impulse start phase is selectable when the drag torque is large, in which case the electrical device is connected to the flywheel (S) after the start clarification phase.
R) Clutch (K) before clutch (K) is connected
The starting / driving unit according to any one of claims 3 to 5, wherein the starting / driving unit is started and rotated under a dissociated state. 7. The starting / driving unit according to claim 3, wherein, when the drag torque is small, the phase shifts to the direct start phase without interruption. 8. In the case of a drag torque which is still insufficient for an impulse start, a dry impulse start phase (without ignition and fuel injection) is introduced before the impulse start, in which the engine control unit (MS)
7. The start-up / drive unit according to claim 6, wherein synchronization and possibly pre-injection are performed using G).