Timing system mounting method and vehicle

Abstract

The present disclosure relates to the technical field of vehicles, and particularly relates to a timing system installation method and a vehicle. The timing system installation method comprises: establishing a corresponding relationship between a phase of a camshaft and a rotational torque of the camshaft on a valve spring; selecting one of the phases in which the rotational torque of the camshaft is not zero as an installation phase; installing the camshaft and a crankshaft by using the installation phase, and calculating a limit installation phase deviation of the camshaft, the direction of the limit installation phase deviation being the same as the direction of the rotational torque of the camshaft at the installation phase. By making the camshaft be acted on by an external force applied by the valve spring during installation and be deviated in only one direction at the installation phase, the limit installation phase deviation can be deviated in one direction instead of being randomly deviated in two directions, and the limit installation phase deviation can be calibrated as an inherent property of the engine by using an EMS control model, so that random errors can be reduced, the installation precision of the camshaft can be improved, and the engine control precision can be improved.

Description

Technical Field

[0001] This disclosure relates to the field of vehicle technology, and more particularly to a timing system installation method and a vehicle. Background Technology

[0002] The opening and closing of engine valves have a strict relative relationship with the crankshaft angle / phase, and the timing system is used to ensure the angle / phase relationship between the two.

[0003] Camshaft installation in timing systems typically employs two methods: pinless installation and pin-mounted installation. Pinless installation uses camshaft fixtures to ensure the mounting angle between the camshaft and crankshaft. However, due to installation process requirements, the camshaft fixture has an installation clearance to allow it to engage during assembly. This clearance causes a perpendicularity deviation when the camshaft fixture engages the camshaft, resulting in a random angular phase deviation. Ultimately, this phase deviation will be randomly distributed between positive and negative limits. Fluctuations in this phase deviation affect the accuracy of the EMS control model, thereby impacting engine control accuracy and affecting engine performance such as ignition, fuel consumption, and knocking.

[0004] Therefore, there is an urgent need for a timing system installation method and vehicle to solve the above problems. Summary of the Invention

[0005] To address the aforementioned technical problems, this disclosure provides a timing system installation method and a vehicle.

[0006] Firstly, this disclosure provides a timing system installation method, including:

[0007] Establish the correspondence between the camshaft phase and the rotational torque of the valve spring on the camshaft;

[0008] Select one of the phases in which the rotational torque on the camshaft is non-zero as the installation phase;

[0009] The camshaft and crankshaft are installed using the aforementioned installation phase, and the limiting installation phase deviation of the camshaft is calculated. The direction of the limiting installation phase deviation is the same as the direction of the rotational torque on the camshaft at the installation phase.

[0010] Optionally, the timing system installation method further includes, after calculating the limiting installation phase deviation:

[0011] The profile of the camshaft was redesigned to compensate for the limit installation phase deviation;

[0012] The camshaft is redesigned for installation.

[0013] Optionally, mounting with a redesigned camshaft includes mounting the redesigned camshaft in any phase where the direction of the rotational torque is the same as the mounting phase.

[0014] Optionally, calculating the limit installation phase deviation includes: obtaining the installation clearance of the camshaft tooling, the camshaft design parameters, and the geometric parameters of the valve mechanism, and calculating the limit installation phase deviation based on the installation clearance of the camshaft tooling, the camshaft design parameters, and the geometric parameters of the valve mechanism.

[0015] Optionally, establishing the correspondence between the camshaft phase and the rotational torque of the valve spring on the camshaft includes:

[0016] Establish the correspondence between the phase of the intake camshaft and the rotational torque of the valve spring on the intake camshaft, and establish the correspondence between the phase of the exhaust camshaft and the rotational torque of the valve spring on the exhaust camshaft.

[0017] Selecting one of the phases of the camshaft where the rotational torque is not zero as the installation phase includes:

[0018] Choose one of the phases where the rotational torque on both the intake and exhaust camshafts is not zero as the installation phase;

[0019] Optionally, the camshaft and crankshaft are installed using a phase-adjustment method, and the limiting phase-adjustment deviation of the camshaft is calculated, including:

[0020] The intake camshaft, exhaust camshaft, and crankshaft are installed using phase-adjustment methods, and the limit phase deviations of the intake camshaft and exhaust camshaft are calculated separately.

[0021] Optionally, calculating the limit installation phase deviation includes: obtaining the installation clearance of the camshaft tooling, and calculating the limit installation phase deviation based on the installation clearance of the camshaft tooling.

[0022] Optionally, after selecting one of the phases where the rotational torque on the camshaft is not zero as the installation phase, the method further includes: obtaining the direction of the rotational torque on the camshaft at the installation phase.

[0023] Optionally, after calculating the limit installation phase deviation, the method further includes: redesigning the camshaft based on the direction of the rotational torque on the camshaft at the installation phase and the limit installation phase deviation, and compensating for the limit installation phase deviation.

[0024] Secondly, this disclosure provides a vehicle that employs the timing system installation method described in the first aspect.

[0025] The technical solution provided in this disclosure has the following advantages compared with the prior art:

[0026] By establishing the correspondence between the camshaft phase and the rotational torque exerted by the valve springs on the camshaft, one of the phases where the rotational torque on the camshaft is non-zero is selected as the installation phase. The camshaft and crankshaft are installed using the installation phase, and the limiting installation phase deviation is calculated. The direction of the limiting installation phase deviation is the same as the direction of the rotational torque exerted on the camshaft at the installation phase. By ensuring that the camshaft is subjected to the external force applied by the valve springs during installation and deviates in only one direction at the installation phase, the limiting installation phase deviation can be biased in one direction instead of randomly biased in two directions, thereby reducing random errors and improving the installation accuracy of the camshaft. Furthermore, the limiting installation phase deviation can be calibrated as an inherent attribute of the engine through the EMS control model, thereby improving engine control accuracy and reducing the impact on engine ignition, fuel consumption, and knock performance. Attached Figure Description

[0027] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0028] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a flowchart of the timing system installation method described in the embodiments of this disclosure;

[0030] Figure 2 This is a schematic diagram showing the relationship between the phase of the camshaft and the rotational torque of the valve spring according to an embodiment of this disclosure.

[0031] Figure 3 A schematic diagram of the ideal mounting configuration for the camshaft;

[0032] Figure 4 A schematic diagram of a state where the camshaft's phase deviation is at its limit;

[0033] Figure 5 This is a schematic diagram of another state of the limiting phase deviation of the camshaft.

[0034] in,

[0035] 1. Camshaft; 2. Camshaft tooling. Detailed Implementation

[0036] To better understand the above-mentioned objectives, features, and advantages of this disclosure, the solutions disclosed herein will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0037] Numerous specific details are set forth in the following description in order to provide a full understanding of this disclosure, but this disclosure may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some, and not all, of the embodiments of this disclosure.

[0038] Timing system: The opening and closing of engine valves have a strict relative relationship with the crankshaft angle / phase. The timing system is used to ensure the angle / phase relationship between the two.

[0039] Camshaft fixture 2: A special tool used to install the camshaft and ensure the installation position and angle of camshaft 1.

[0040] Camshaft mounting phase: The mounting angle / phase of camshaft 1 relative to crankshaft.

[0041] Camshaft phase deviation: The deviation between the actual angle / phase and the designed angle / phase of the camshaft after installation.

[0042] Camshaft installation includes: locking the engine crankshaft in the specified installation phase; using camshaft fixture 2 to fix the camshaft installation phase; connecting camshaft 1 to the camshaft sprocket, and connecting the sprocket to the crankshaft via a chain; installing a chain tensioner to tension the chain; and tightening the bolts connecting the camshaft sprocket and the camshaft. Specifically, the camshaft timing installation process is as follows: First, lock the engine crankshaft in the specified installation phase; use camshaft fixture 2 to fix the camshaft installation phase; connect camshaft 1 to the camshaft sprocket, and connect the sprocket to the crankshaft via a chain; then install a chain tensioner to tension the chain; finally, tighten the bolts connecting the camshaft sprocket and the camshaft. At this point, the phase relationship between camshaft 1 and the crankshaft is locked. However, because camshaft fixture 2 has installation clearance, using the fixture to install the camshaft will result in camshaft phase deviation.

[0043] In this embodiment of the present disclosure, the camshaft 1 can be either an intake camshaft or an exhaust camshaft. Correspondingly, when the camshaft 1 is an intake camshaft, the valve spring is an intake valve spring; when the camshaft 1 is an exhaust camshaft, the valve spring is an exhaust valve spring.

[0044] like Figure 1 As shown, this disclosure provides a timing system installation method, which includes the following steps:

[0045] S1. Establish the correspondence between the phase of camshaft 1 and the rotational torque of the valve spring on camshaft 1.

[0046] Specifically, the rotational torque of the valve spring on the camshaft 1 at different installation phases is obtained through calculation or measurement, thus establishing the correspondence between the installation phase of the camshaft 1 and the rotational torque of the valve spring on the camshaft 1. The correspondence between the phase of the camshaft 1 and the rotational torque of the valve spring on the camshaft 1 is as follows: Figure 2 As shown, it can be understood that when camshaft 1 is an intake camshaft, a correspondence is established between the intake camshaft and the rotational torque of the intake valve spring on the intake camshaft. When camshaft 1 is an exhaust camshaft, a correspondence is established between the exhaust camshaft and the rotational torque of the exhaust valve spring on the exhaust camshaft. Specifically, in Figure 2 In the diagram, A represents the curve showing the relationship between the phase of the intake camshaft and the rotational torque of the valve spring on the intake camshaft, while B represents the curve showing the relationship between the phase of the exhaust camshaft and the rotational torque of the valve spring on the exhaust camshaft.

[0047] S2. Select one of the phases of camshaft 1 where the rotational torque is not zero as the installation phase.

[0048] Reference Figure 2 The rotational torque above the phase line is defined as positive, and the rotational torque below the phase line is defined as negative. Taking the intake camshaft as an example, from... Figure 2 It can be seen that in some phases, the rotational torque exerted on the intake camshaft by the valve springs is positive; in some phases, it is negative; and in the remaining phases, the rotational torque exerted on the intake camshaft by the valve springs is zero. Therefore, the selected installation phase corresponds to a non-zero rotational torque on camshaft 1, causing camshaft 1 to be biased in one direction by the rotational torque, resulting in a phase deviation in one direction as well. Preferably, the phase with a larger rotational torque on camshaft 1 is used as the installation phase.

[0049] S3. Install camshaft 1 and crankshaft using the installation phase, and calculate the limit installation phase deviation of camshaft 1. The direction of the limit installation phase deviation is the same as the direction of the rotational torque on camshaft 1 at the installation phase.

[0050] It is understandable that, such as Figures 3 to 5As shown, in the prior art, when the camshaft 1 is installed using the camshaft fixture 2, the installation clearance h of the camshaft fixture 2 causes random phase deviations in two directions for the camshaft 1. Measurements of the phase deviations of production engines show that the limit phase deviation is approximately ±α°, meaning the random phase deviation is between -α° and +α°. Therefore, the random phase deviation affects the accuracy of the EMS control model. However, by selecting the phase where the rotational torque of the valve spring on the camshaft 1 is not zero as the installation phase, when the camshaft 1 is installed at this phase, it naturally deflects in one direction due to the force of the valve spring. Therefore, the phase deviation is only in one direction, not randomly deflected in two directions. Furthermore, after calculating the limit installation phase deviation, the limit installation phase deviation can be calibrated as an inherent attribute of the engine through the EMS control model. This eliminates the phase deviation at the software control level. Without changing the existing process flow, random errors can be reduced, the installation accuracy of the camshaft 1 can be improved, thereby improving the engine's control accuracy and reducing the impact on engine ignition, fuel consumption, and knock performance.

[0051] Furthermore, referring to Figure 1 In some embodiments, the timing system installation method described above further includes:

[0052] S4. Redesign the camshaft profile 1 to compensate for the limit installation phase deviation.

[0053] S5. Install using a redesigned camshaft 1.

[0054] As described above, camshaft 1 has a limiting installation phase deviation in one direction. Therefore, based on this limiting installation phase deviation, the profile of camshaft 1 is redesigned. During the design and manufacturing of camshaft 1, this fixed installation deviation is compensated into the design value. This structurally eliminates the aforementioned limiting installation phase deviation, ultimately ensuring that the phase deviation of the actually installed camshaft 1 is near 0°, thus improving the installation accuracy of camshaft 1. It is understandable that the rotational torque exerted by the valve spring on camshaft 1 causes the phase deviation of camshaft 1 to be biased only in one direction, rather than randomly biased in two directions. This allows for the redesign of camshaft 1 to compensate for the limiting installation phase deviation.

[0055] This timing system installation method can reduce random deviations in the installation phase. This method is suitable for engines using camshaft 1 to control valve timing, achieving an engine timing installation accuracy of approximately ±1°. In other words, the method for compensating for limit installation phase deviations when redesigning camshaft 1 involves adding a reverse deviation to the camshaft 1 design drawings. After installation, these deviations are superimposed and cancel each other out. For example, if zero deviation (0° deviation) is required after installation, but actual installation results in a -β° deviation, then a β° deviation needs to be directly designed into the camshaft 1 design drawings to cancel out the -β° deviation. The redesigned camshaft 1 will then achieve a 0° deviation after installation. Without this timing system installation method, the phase deviation of camshaft 1 is not a fixed value but a range, such as +α° to -α°, making compensation impossible in the camshaft 1 design drawings.

[0056] Furthermore, the timing system installation method described above also includes S21 between S2 and S3: determining the direction of the rotational torque on the camshaft 1 at the installation phase. Thus, in S4, the direction of the limiting installation phase deviation can be determined, thereby allowing for the compensation design of the camshaft 1 based on the limiting installation phase deviation and its direction.

[0057] It is understandable that once the direction of the rotational torque of the valve spring on the camshaft 1 is determined, the direction of the limit installation phase deviation of the camshaft 1 from the installation phase is determined. Thus, by redesigning the camshaft profile, compensation can be made in the opposite direction to the limit installation phase deviation to reduce or even eliminate the limit installation phase deviation.

[0058] Furthermore, in some embodiments, mounting with a redesigned camshaft 1 includes mounting the redesigned camshaft 1 with any phase in which the direction of the rotational torque corresponding to the mounting phase is the same.

[0059] It is understandable that when the direction of the rotational torque exerted by the valve spring on the camshaft 1 in different phases is the same, the direction of the limit installation phase deviation of the camshaft 1 is the same. Therefore, any one of the phases can be selected to install the redesigned camshaft 1.

[0060] It should be noted that by using camshaft 1 without compensating for installation phase deviation and installing it under the rotational torque of the valve spring, the actual phase deviation of camshaft 1 is ultimately stabilized near the limit installation phase deviation. This method can also achieve a stable and consistent installation phase of camshaft 1. Reducing phase deviation fluctuations remains highly valuable for practical engineering applications.

[0061] Furthermore, when installing the phase-mounted camshaft 1, the camshaft 1 can rotate naturally under the external force applied by the valve spring. That is, when installing the phase-mounted camshaft 1, the camshaft 1 rotates naturally under the reaction force of the valve spring. This embodiment of the present disclosure selects the installation phase subject to the rotational torque of the valve spring, so that the camshaft 1 is subjected to an external force during installation. This force causes the phase deviation of the camshaft 1 during installation to naturally deviate in one direction, rather than randomly deviating in two directions, ultimately achieving a phase deviation distribution of the camshaft 1 near a limit phase deviation.

[0062] Furthermore, calculating the limit installation phase deviation includes: obtaining the installation clearance of the camshaft fixture 2, the design parameters of the camshaft 1, and the geometric parameters of the valve mechanism, and calculating the limit installation phase deviation based on the installation clearance of the camshaft fixture 2, the design parameters of the camshaft 1, and the geometric parameters of the valve mechanism.

[0063] Alternatively, the camshaft design can be compensated directly using the existing limit phase deviation ±α°. This limit phase deviation is related to the clearance of the camshaft tooling 2 and can be calculated or measured from the engine on the production line. By selecting one of the phases where the rotational torque on the camshaft 1 is not zero as the installation phase, when the camshaft 1 is in the installation phase, due to the effect of the rotational torque, the deviation of the camshaft 1 is only biased in one direction, such as the positive direction (defined as a phase deviation of 0 to +α° as positive, and a phase deviation of -α° to 0 as negative). In this case, directly redesigning the camshaft and providing -α° compensation can also reduce random errors and improve the installation accuracy of the camshaft 1.

[0064] Specifically, calculating the limit installation phase deviation includes: obtaining the installation clearance of the camshaft fixture 2, and calculating the limit installation phase deviation based on the installation clearance of the camshaft fixture 2. After selecting one of the phases where the rotational torque on the camshaft 1 is not zero as the installation phase, the calculation also includes: obtaining the direction of the rotational torque on the camshaft 1 at the installation phase. After calculating the limit installation phase deviation, the calculation further includes: redesigning the camshaft 1 based on the direction of the rotational torque on the camshaft 1 at the installation phase and the limit installation phase deviation, and compensating for the limit installation phase deviation.

[0065] This disclosure provides a timing system installation method that utilizes the rotational torque of the valve spring on the intake camshaft to reduce random deviations in the intake camshaft mounting phase, as detailed below:

[0066] ① Calculate / measure the rotational torque of the valve spring on the intake camshaft to obtain the relationship between the phase of the intake camshaft and the rotational torque;

[0067] ② Select the installation phase so that the intake camshaft has rotational torque at the same time.

[0068] ③ Use this phase-locking crankshaft to install the intake camshaft. When installing the intake camshaft using this tooling, because the intake camshaft has rotational torque, the installation deviation is no longer a random deviation, but a fixed limit installation phase deviation. Assume that the limit installation phase deviation of the intake camshaft is +3° at this point.

[0069] ④ Redesign the intake camshaft profile to compensate for the +3° deviation of the intake camshaft.

[0070] ⑤ By using an intake camshaft with compensating for deviations, the final installation phase deviation will be around 0°.

[0071] By statistically analyzing the phase deviation of engines at the factory, this method reduces the engine's phase deviation from approximately ±3° crankshaft angle to approximately ±1° crankshaft angle. The timing system installation method provided in this disclosure can reduce random deviations in the installation phase. This method is applicable to engines using camshaft-controlled valve timing, achieving an engine timing installation accuracy of approximately ±1°.

[0072] It should be noted that the timing system installation method described above can also be applied to the exhaust camshaft.

[0073] Optionally, the above timing system installation method is also applicable to the simultaneous installation of intake and exhaust camshafts. Specifically, establishing the correspondence between the camshaft phase and the rotational torque of the valve springs on the camshaft includes: establishing the correspondence between the intake camshaft phase and the rotational torque of the valve springs on the intake camshaft, and establishing the correspondence between the exhaust camshaft phase and the rotational torque of the valve springs on the exhaust camshaft, such as... Figure 2 As shown. The above selection of one phase of the camshaft where the rotational torque is not zero as the installation phase includes: selecting one phase of both the intake and exhaust camshafts where the rotational torque is not zero as the installation phase; the above calculation of the camshaft's limit installation phase deviation using the installation phase includes: using the installation phase to install the intake camshaft, exhaust camshaft, and crankshaft, and calculating the limit installation phase deviation of the intake and exhaust camshafts respectively. Subsequently, the profiles of the intake and exhaust camshafts are redesigned and compensated for separately.

[0074] It is understandable that the phase of the intake camshaft or exhaust camshaft, which is subject to rotational torque, should be selected based on the crankshaft angle (the phase with the larger torque is recommended, such as...). Figure 2The rectangular area marked with a dashed line in the image shows the area where the intake and exhaust camshafts are simultaneously subjected to external forces during installation. These forces cause the phase deviation of each camshaft to naturally shift in one direction, rather than randomly shifting in two directions. Ultimately, this ensures that their respective phase deviations are distributed near a critical phase deviation. Then, the phase deviation is compensated for during the design of the intake and exhaust camshafts. That is, this fixed installation deviation is compensated for into the design value during the design and manufacturing of camshaft 1, ultimately ensuring that the actual phase deviation of camshaft 1 is near 0°.

[0075] This disclosure also provides a vehicle including the timing system installation method described above. Since the vehicle provided in this disclosure uses the timing system installation method described in this disclosure, it has the same advantages as the timing system installation method described in this disclosure, and will not be repeated here.

[0076] A vehicle that uses the above-described timing system installation method.

[0077] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the term "comprising" or any other variations thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0078] The above are merely specific embodiments of this disclosure, enabling those skilled in the art to understand or implement this disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to these embodiments, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A timing system installation method, characterized in that, include: Establish the correspondence between the camshaft phase and the rotational torque of the valve springs on the camshaft; Select one of the phases in which the rotational torque on the camshaft is non-zero as the installation phase; The camshaft and crankshaft are installed using the aforementioned installation phase, and the limiting installation phase deviation of the camshaft is calculated. The direction of the limiting installation phase deviation is the same as the direction of the rotational torque on the camshaft at the installation phase. The profile of the camshaft was redesigned to compensate for the limit installation phase deviation; The camshaft is redesigned for installation.

2. The timing system installation method according to claim 1, characterized in that, Mounting with a redesigned camshaft includes mounting the redesigned camshaft in any phase where the direction of the rotational torque is the same as the mounting phase.

3. The timing system installation method according to claim 1, characterized in that, Calculating the limit installation phase deviation includes: obtaining the installation clearance of the camshaft tooling, the camshaft design parameters, and the geometric parameters of the valve mechanism; and calculating the limit installation phase deviation based on the installation clearance of the camshaft tooling, the camshaft design parameters, and the geometric parameters of the valve mechanism.

4. The timing system installation method according to claim 1, characterized in that, Establishing the correspondence between the camshaft phase and the rotational torque of the valve springs on the camshaft includes: Establish the correspondence between the phase of the intake camshaft and the rotational torque of the valve spring on the intake camshaft, and establish the correspondence between the phase of the exhaust camshaft and the rotational torque of the valve spring on the exhaust camshaft. Selecting one of the phases of the camshaft where the rotational torque is not zero as the installation phase includes: Choose one of the phases where the rotational torque on both the intake and exhaust camshafts is not zero as the installation phase.

5. The timing system installation method according to claim 4, characterized in that, By using the installation phase method to install the camshaft and crankshaft, the limit installation phase deviation of the camshaft is calculated, including: The intake camshaft, exhaust camshaft, and crankshaft are installed using phase-adjustment methods, and the limit phase deviations of the intake camshaft and exhaust camshaft are calculated separately.

6. The timing system installation method according to any one of claims 1-2 and 4-5, characterized in that, The calculation of the limit installation phase deviation includes: obtaining the installation clearance of the camshaft tooling, and calculating the limit installation phase deviation based on the installation clearance of the camshaft tooling.

7. The timing system installation method according to claim 6, characterized in that, After selecting one of the phases where the rotational torque on the camshaft is not zero as the installation phase, the method further includes: obtaining the direction of the rotational torque on the camshaft at the installation phase.

8. The timing system installation method according to claim 7, characterized in that, After calculating the limit installation phase deviation, the process also includes: redesigning the camshaft based on the direction of the rotational torque on the camshaft at the installation phase and the limit installation phase deviation, and compensating for the limit installation phase deviation.

9. A vehicle, characterized in that, The timing system installation method according to any one of claims 1 to 8 is adopted.

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