Method and system for evaluating cold assembly deformation of press-in thin-wall cylinder liner

Abstract

The application provides a press-in thin-wall cylinder sleeve cold-state assembly deformation evaluation method and system, comprising: determining a set of to-be-evaluated cylinder holes in a measured engine, and establishing a unified measurement coordinate corresponding to the set of to-be-evaluated cylinder holes; collecting circumferential profile data of each cylinder hole in the set of to-be-evaluated cylinder holes, and constructing a data set covering all the to-be-evaluated cylinder holes; performing data alignment and index calculation on the full-cylinder-hole profile data sets in three states to obtain the circumferential, cylindricity and Fourier order component of each state, each cylinder hole and each set axial section; constructing a multi-index topography envelope, and outputting a cylinder hole assembly deformation evaluation and identification result based on the multi-index topography envelope. The application avoids misjudgment caused by only measuring a single cylinder hole or only relying on a single cylindricity and cylindricity index, and can adapt to thin-wall cylinder sleeve cold-state assembly deformation evaluation of different cylinder numbers, different cylinder diameters, different cylinder head structures and different assembly processes.

Description

Technical Field

[0001] This application belongs to the field of thin-walled cylinder liner assembly morphology evaluation technology, and particularly relates to a method and system for evaluating cold assembly deformation of press-fit thin-walled cylinder liners. Background Technology

[0002] To meet the weight reduction requirements of aviation diesel engines, lightweight automotive diesel engines, and small high-power-density engines, the structure of aluminum alloy engine blocks combined with dry-pressed thin-walled cylinder liners is gradually being adopted. This structure achieves tight contact between the cylinder liner and the cylinder bore of the aluminum engine block through a room-temperature interference fit, which can reduce material redundancy in the cylinder area of ​​the engine block and reduce the risk of interface separation, cylinder liner cracking, or detachment caused by the thermal expansion difference between aluminum and iron materials and casting residual stress in cast-in cylinder liners.

[0003] However, press-fit thin-walled cylinder liners have a smaller radial wall thickness and lower overall deformation stiffness. After cold press-fitting, the cylinder liner must simultaneously withstand the basic radial compressive stress generated by the interference fit, the constraint differences caused by the non-uniformity of local stiffness in the engine block, the axial tensile and compressive loads generated by the pre-tightening of the cylinder head bolts, and the local compression effect of the cylinder head gasket. Under the combined action of these loads, the inner surface of the cylinder bore will exhibit varying degrees of out-of-roundness, cylindricity changes, and order distortion.

[0004] For the friction pair consisting of piston, piston rings, and cylinder liner, low-order long-wave deformation alters the circumferential contact pressure distribution of the piston rings, while high-order short-wave distortion can cause localized piston ring suspension, increased blow-by, increased oil consumption, and premature wear. In engineering practice, process cylinder heads or torque plates are often used to perform stress-state honing or stress-state testing on the cylinder bores in order to simulate cylinder bore deformation under cylinder head preload conditions.

[0005] However, process cylinder heads typically differ from actual cylinder heads in materials, local structure, contact stiffness, and load transfer paths. Using the same assembly process does not guarantee that their effects on cylinder bore deformation will be completely equivalent. Measuring only a single cylinder bore, or only under a single condition, makes it impossible to distinguish the roles of the initial press-fit morphology, process assembly boundaries, and actual assembly boundaries. For multi-cylinder engines, the support boundaries for end cylinders, intermediate cylinders, or different cylinder bank positions may differ, necessitating comprehensive measurements of all cylinder bores to be evaluated under every condition.

[0006] Existing technologies often use single roundness or cylindricity as the basis for evaluating cylinder bore quality, making it difficult to distinguish different orders of deformation caused by factors such as interference fit, non-uniform engine block support stiffness, discrete preload of cylinder head bolts, and local compression of cylinder head gaskets. In particular, fourth-order petal-shaped distortion usually manifests as four alternating peaks and valleys in the circumferential direction, which is closely related to bolt load transmission and the boundary near the cylinder head mating surface. It is difficult to determine its source and risk location using only maximum roundness or average cylindricity. Summary of the Invention

[0007] In view of this, this application aims to propose a method and system for evaluating the cold assembly deformation of press-fit thin-walled cylinder liners, in order to solve the problems in the existing evaluation of thin-walled cylinder liner assembly deformation, such as incomplete measurement objects, difficulty in identifying the boundary differences between the process cylinder head and the actual cylinder head, and the inability of a single geometric index to reflect the order distortion characteristics.

[0008] To achieve the above objectives, the technical solution of this application is implemented as follows: In a first aspect, this application provides a method for evaluating the cold assembly deformation of press-fit thin-walled cylinder liners, including: The set of cylinder bores to be evaluated in the engine under test is determined, and a unified measurement coordinate system corresponding to the set of cylinder bores to be evaluated is established to determine the zero position of the circumferential angle, the axial height reference, the cylinder bore numbering rules, and the cross-sectional correspondence. Collect the circumferential contour data of each cylinder bore in the set of cylinder bores to be evaluated, and construct a dataset covering all cylinder bores to be evaluated. The dataset includes a free state full cylinder bore contour dataset, a process cylinder head state full cylinder bore contour dataset, and a real cylinder head state full cylinder bore contour dataset. Data alignment and index calculation were performed on the full cylinder bore profile datasets under three states to obtain the circumference, cylindricity and Fourier order components of each state, each cylinder bore and each set axial section. A multi-index morphological envelope is constructed, which includes overall morphological index, local sensitive area index, order modal index, cylinder bore consistency index, and state difference index. Based on the multi-index morphological envelope, the cylinder bore assembly deformation evaluation and identification results are output.

[0009] Secondly, based on the same inventive concept, this application also provides a cold assembly deformation evaluation system for press-fit thin-walled cylinder liners, comprising: The cylinder bore set determination module is configured to determine the set of cylinder bores to be evaluated in the engine under test, and to establish a unified measurement coordinate system corresponding to the set of cylinder bores to be evaluated, so as to determine the zero position of the circumferential angle, the axial height reference, the cylinder bore numbering rules and the cross-sectional correspondence. The cylinder bore profile dataset construction module is configured to collect the circumferential profile data of each cylinder bore in the set of cylinder bores to be evaluated, and construct a dataset covering all cylinder bores to be evaluated. The dataset includes a free state full cylinder bore profile dataset, a process cylinder head state full cylinder bore profile dataset, and a real cylinder head state full cylinder bore profile dataset. The data processing module is configured to perform data alignment and index calculation on the full cylinder bore profile dataset under three states to obtain the circumference, cylindricity and Fourier order components of each state, each cylinder bore and each set axial section. The evaluation and identification output module is configured to construct a multi-index morphology envelope that includes overall morphology index, local sensitive area index, order modal index, cylinder bore consistency index, and state difference index, and output the cylinder bore assembly deformation evaluation and identification results based on the multi-index morphology envelope.

[0010] Thirdly, based on the same inventive concept, this application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the method described in the first aspect.

[0011] Fourthly, based on the same inventive concept, this application also provides a non-transitory computer-readable storage medium, wherein the non-transitory computer-readable storage medium stores computer instructions for causing the computer to perform the method as described in the first aspect.

[0012] Compared with the prior art, the method and system for evaluating the cold assembly deformation of press-fit thin-walled cylinder liners described in this application have the following advantages: This application avoids misjudgments caused by measuring only a single cylinder bore or relying solely on single roundness or cylindricity indicators. It can uniformly measure and analyze all cylinder bores to be evaluated in free state, process cylinder head state, and actual cylinder head state. It is suitable for evaluating the cold assembly deformation of thin-walled cylinder liners with different numbers of cylinders, different cylinder diameters, different cylinder head structures, and different assembly processes, thereby improving the completeness and accuracy of identifying the cold assembly deformation of thin-walled cylinder liners. Attached Figure Description

[0013] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a flowchart of a cold assembly deformation evaluation method for press-fit thin-walled cylinder liners as described in an embodiment of this application. Figure 2 This is a schematic diagram of the cylinder bore three-state progressive measurement assembly as described in the embodiments of this application; Figure 3 This is a schematic diagram of the Fourier order analysis and morphological envelope of the circular contour described in the embodiments of this application; Figure 4 This is a schematic diagram of the structure of a cold assembly deformation evaluation system for press-fit thin-walled cylinder liners as described in an embodiment of this application; Figure 5 This is a schematic diagram of the hardware structure of the electronic device described in an embodiment of this application.

[0014] Explanation of reference numerals in the attached figures: 1- Engine body; 2- Thin-walled cylinder liner; 3- Process cylinder head; 4- Actual cylinder head; 5- Bolt preload. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0016] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0017] The embodiments of this application are described in detail below with reference to the accompanying drawings.

[0018] Please see Figure 1 As shown in the figure, this embodiment provides a method for evaluating the deformation of a press-fit thin-walled cylinder liner during cold assembly, which specifically includes the following steps: Step S10: Determine the set of cylinder bores to be evaluated in the engine under test, and establish a unified measurement coordinate system corresponding to the set of cylinder bores to be evaluated, so as to determine the zero position of the circumferential angle, the axial height reference, the cylinder bore numbering rules, and the cross-sectional correspondence.

[0019] Specifically, in this embodiment, before measurement, the set of cylinder bores to be evaluated is first determined. Based on the number of cylinders, cylinder bank configuration, cylinder bore numbering rules, and evaluation purpose of the engine under test, the set of cylinder bores to be evaluated is determined. This set can be all cylinder bores of the engine under test, or it can be all cylinder bores selected according to the test purpose. Once the evaluation set is determined, measurements are performed on each cylinder bore in the same set under free state, process cylinder head state, and actual cylinder head state to avoid misassociating different states with different cylinder bores.

[0020] Secondly, a unified measurement coordinate system is established on the same engine block, the same set of thin-walled cylinder liners, and the same contour measurement system to determine the zero point of the circumferential angle, the axial height reference, and the corresponding relationship of the cross sections. The zero point of the circumferential angle and the axial height reference remain consistent in the free state, the process cylinder head state, and the actual cylinder head state, so that the contour data in the three states can correspond point by point according to the cylinder bore, axial section, and circumferential angle. The number, position, and spacing of the axial sections are determined according to the specific engine structure. They can be appropriately densified in the area near the cylinder head mating surface, or adjusted according to the piston ring working area, the lower support relationship of the cylinder liner, and the capability of the measuring equipment, without being limited by fixed values.

[0021] The test object is the engine block of a press-fit thin-walled cylinder liner engine. This engine can be a single-cylinder engine, a multi-cylinder inline engine, a V-type engine, a horizontally opposed engine, or other engines with press-fit thin-walled cylinder liners. This embodiment does not limit the number of cylinders.

[0022] In this embodiment, for the evaluation of the whole machine assembly, the set of cylinder bores to be evaluated is preferably all the cylinder bores of the engine under test; for the verification of local structures or special tests, a specified cylinder bank, a specified cylinder bore, or a specified sample can also be used as the set of cylinder bores to be evaluated, but the same set must be maintained in all three states.

[0023] Step S20: Collect the circumferential contour data of each cylinder bore in the set of cylinder bores to be evaluated, and construct a dataset covering all cylinder bores to be evaluated. The dataset includes a free state full cylinder bore contour dataset, a process cylinder head state full cylinder bore contour dataset, and a real cylinder head state full cylinder bore contour dataset.

[0024] Specifically, in this embodiment, such as Figure 2 As shown, in the free state, the thin-walled cylinder liner 2 has been press-fitted but the cylinder head has not been assembled. The measurement system (with the profile measuring instrument inserted into the thin-walled cylinder liner 2) collects circumferential profile data for each cylinder bore in the set of cylinder bores to be evaluated, forming a free-state full cylinder bore profile dataset P0. P0 is used to characterize the initial shape of the press-fitting and the basic support boundary of the engine block, rather than the profile of a single cylinder bore.

[0025] Subsequently, the process cylinder head 3 or a process loading component used to simulate the cylinder head assembly boundary is installed on the engine block 1, and a bolt preload 5 is applied according to the corresponding engine process requirements. The preload can be applied by torque loading, angle loading, axial force loading, or a combination thereof. The specific loading levels, torque, or axial force magnitude is determined according to different engines and different process cylinder head structures, and is not limited to fixed values. After loading is completed, contour data is collected for each cylinder bore within the same set of cylinder bores to be evaluated, forming a full cylinder bore contour dataset P1 of the process cylinder head state.

[0026] Afterwards, the process cylinder head 3 or the process loading component is removed, and the actual cylinder head 4 is installed. Pre-tightening is then performed according to the actual engine assembly process. The measurement system acquires the full cylinder bore profile dataset P2 of the actual cylinder head state without changing the cylinder bore set, angular zero position, and axial section definition.

[0027] Therefore, P0, P1, and P2 are all datasets covering all cylinder bores to be evaluated, rather than data representing a single cylinder bore. This allows for comparison of state differences on a cylinder bore-by-cylinder, cross-sectional, and angle-by-angle basis. This measurement method can identify changes in the same cylinder bore under different assembly conditions, as well as boundary differences between different cylinder bores under the same condition.

[0028] It should be noted that the cylinder bore objects measured in the three states are consistent, and each state is used to measure each cylinder bore in the set of cylinder bores to be evaluated. When a cylinder bore cannot obtain valid data due to measurement conditions, the cylinder bore is marked as invalid or removed from the same evaluation batch in all three states to ensure that the comparison objects are consistent between states.

[0029] Step S30: Align the full cylinder bore profile datasets under the three states and calculate the indices to obtain the circumference, cylindricity and Fourier order components of each state, each cylinder bore and each set axial section.

[0030] Specifically, in this embodiment, multiple measuring sections are arranged axially for each cylinder bore. The number of sections, the spacing between sections, and the location of sections are determined based on the engine cylinder diameter, stroke, cylinder liner support length, piston ring working area, cylinder head bolt arrangement, and the capabilities of the measuring equipment. The axial sections at least cover the top area near the cylinder head mating surface, the piston ring working area, and the lower cylinder liner support area. For areas sensitive to assembly loads, the number of sections can be appropriately increased; for areas with gentle deformation changes, the spacing between sections can be appropriately increased.

[0031] The Fourier order components are obtained by decomposing the circumferential radial deviation function of each axial section into its order components, and then considering any state... Any cylinder bore any axial position The circumferential radial deviation at the location is expressed as In the formula, The angle is circumferential. The Fourier order components include at least a set order for identifying low-order long-wave distortion and high-order short-wave distortion, and the amplitude, phase and axial position of the corresponding order are extracted.

[0032] The Fourier order components include a second-order elliptic component and a fourth-order petal-shaped component. The second-order elliptic component is used to characterize the low-order out-of-roundness characteristics of the cylinder bore alternating expansion and contraction along two principal directions. It is commonly used to identify non-uniform body support stiffness, press-fit boundaries, and low-order assembly deformation. The fourth-order petal-shaped component is used to characterize the short-wave distortion characteristics of four alternating peaks and valleys in the circumferential direction. It is commonly used to identify discrete preload of cylinder head bolts, local contact of cylinder gaskets, stress transmission near the cylinder head mating surface, and end boundary effects. In addition to the second and fourth orders, other preset orders can be extracted based on measurement accuracy, cylinder bore out-of-roundness characteristics, and engineering evaluation objectives. For local peak values, this embodiment does not simply discard them, but rather includes them as potential process risks or assembly boundary sensitive points in subsequent morphology envelope evaluation.

[0033] Step S40: Construct a multi-index morphological envelope that includes overall morphological index, local sensitive area index, order modal index, cylinder bore consistency index, and state difference index, and output the cylinder bore assembly deformation evaluation and identification results based on the multi-index morphological envelope.

[0034] Specifically, in this embodiment, such as Figure 4 As shown, a multi-index morphological envelope is established based on the three-state full cylinder bore profile data. This morphological envelope is not based solely on roundness or cylindricity, but simultaneously includes overall morphological indices, local sensitive area indices, order modal indices, cylinder bore consistency indices, and state difference indices.

[0035] Among them, the overall morphology index can include full-height cylindricity or cylindricity within a set height range; the local sensitive area index can include the maximum and average roundness of the top sensitive area, the middle evaluation area, or the lower evaluation area; the order modal index can include the peak, phase, and axial position of the second order, fourth order, and other set orders; the cylinder bore consistency index can be used to describe the response differences between different cylinder bores under the same state; and the state difference index can be used to describe the representative differences between the process cylinder head state and the actual cylinder head state.

[0036] For example, if the cylindricity of the process cylinder head is close to that of the actual cylinder head, but the amplitude, phase, or sensitive bore position of the fourth-order component in the top sensitive region is significantly different, then the two assembly boundaries cannot be considered equivalent solely based on the similarity of cylindricity. Conversely, if the consistency indices of each critical order, critical region, and bore all show similar trends, then the process cylinder head can be considered to have good morphological representativeness of the actual cylinder head.

[0037] It should be noted that the boundaries of each local sensitive area are determined based on the cylinder head mating surface, the cylinder head bolt load transmission range, the piston ring working area, the cylinder liner support relationship, and engine design requirements, and are not limited to a fixed distance range.

[0038] Based on the P0, P1, and P2 state datasets, the system first generates a state index matrix, and then generates a state difference matrix. The state difference matrix can include the changes in the process cylinder head state relative to the free state, the changes in the actual cylinder head state relative to the free state, and the changes in the actual cylinder head state relative to the process cylinder head state.

[0039] Based on this, the system performs dominant deformation order identification, sensitive section identification, cylinder bore consistency evaluation, and process boundary representativeness evaluation, ultimately outputting a multi-index evaluation report. The evaluation report may include the dominant deformation order of each cylinder bore, the location of sensitive axial directions, critical state differences, cylinder bore consistency, and risk level.

[0040] The core of this embodiment lies in evaluation and identification, rather than using process cylinder head calibration amounts, zonal machining pre-compensation amounts, or assembly quality release conclusions as necessary outputs. For application scenarios requiring further process improvements, the evaluation report can serve as the basis for subsequent process calibration, structural optimization, or quality review, but such subsequent actions do not constitute a necessary step in the method of this application.

[0041] The method described in this application avoids misjudgments caused by measuring only a single cylinder bore or relying solely on single roundness or cylindricity indicators. It can uniformly measure and analyze all cylinder bores to be evaluated in free state, process cylinder head state, and actual cylinder head state. It is suitable for evaluating the cold assembly deformation of thin-walled cylinder liners with different numbers of cylinders, different cylinder diameters, different cylinder head structures, and different assembly processes, thereby improving the completeness and accuracy of identifying the cold assembly deformation of thin-walled cylinder liners.

[0042] It should be noted that the above description describes some embodiments of this application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in a different order than that shown in the above embodiments and still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0043] Based on the same inventive concept, and corresponding to the methods of any of the above embodiments, the embodiments of this application also provide a cold assembly deformation evaluation system for press-fit thin-walled cylinder liners.

[0044] like Figure 4 As shown, the cold assembly deformation evaluation system for press-fit thin-walled cylinder liners includes: The cylinder bore set determination module 11 is configured to determine the set of cylinder bores to be evaluated in the engine under test, and to establish a unified measurement coordinate system corresponding to the set of cylinder bores to be evaluated, so as to determine the zero position of the circumferential angle, the axial height reference, the cylinder bore numbering rules and the cross-sectional correspondence. The cylinder bore profile dataset construction module 12 is configured to collect the circumferential profile data of each cylinder bore in the set of cylinder bores to be evaluated, and construct a dataset covering all cylinder bores to be evaluated. The dataset includes a free state full cylinder bore profile dataset, a process cylinder head state full cylinder bore profile dataset, and a real cylinder head state full cylinder bore profile dataset. Data processing module 13 is configured to perform data alignment and index calculation on the full cylinder bore profile dataset under three states to obtain the circumference, cylindricity and Fourier order components of each state, each cylinder bore and each set axial section. The evaluation and identification output module 14 is configured to construct a multi-index morphology envelope that includes overall morphology index, local sensitive area index, order modal index, cylinder bore consistency index and state difference index, and output the cylinder bore assembly deformation evaluation and identification results based on the multi-index morphology envelope.

[0045] For ease of description, the above system is described by dividing it into various modules based on their functions. Of course, in implementing the embodiments of this application, the functions of each module can be implemented in one or more software and / or hardware.

[0046] The system described in the above embodiments is used to implement the corresponding method in any of the foregoing embodiments and has the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0047] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, embodiments of this application also provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the methods described in any of the above embodiments.

[0048] Figure 5 This embodiment illustrates a more specific hardware structure of an electronic device, which may include a processor 1010, a memory 1020, an input / output interface 1030, a communication interface 1040, and a bus 1050. The processor 1010, memory 1020, input / output interface 1030, and communication interface 1040 are interconnected internally via the bus 1050.

[0049] The processor 1010 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this specification.

[0050] The memory 1020 can be implemented in the form of ROM (Read Only Memory), RAM (Random Access Memory), static storage device, dynamic storage device, etc. The memory 1020 can store the operating system and other applications. When the technical solutions provided in the embodiments of this specification are implemented by software or firmware, the relevant program code is stored in the memory 1020 and is called and executed by the processor 1010.

[0051] The input / output interface 1030 is used to connect input / output modules to realize information input and output. The input / output modules can be configured as components in the device (not shown in the figure) or externally connected to the device to provide corresponding functions. Input devices may include keyboards, mice, touch screens, microphones, various sensors, etc., and output devices may include displays, speakers, vibrators, indicator lights, etc.

[0052] The communication interface 1040 is used to connect a communication module (not shown in the figure) to enable communication between this device and other devices. The communication module can communicate via wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.).

[0053] Bus 1050 includes a pathway for transmitting information between various components of the device, such as processor 1010, memory 1020, input / output interface 1030, and communication interface 1040.

[0054] It should be noted that although the above-described device only shows the processor 1010, memory 1020, input / output interface 1030, communication interface 1040, and bus 1050, in specific implementations, the device may also include other components necessary for normal operation. Furthermore, those skilled in the art will understand that the above-described device may only include the components necessary for implementing the embodiments of this specification, and not necessarily all the components shown in the figures.

[0055] The electronic devices described above are used to implement the corresponding methods in any of the foregoing embodiments and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0056] Based on the same inventive concept, corresponding to the methods of any of the above embodiments, this application also provides a non-transitory computer-readable storage medium that stores computer instructions for causing the computer to perform the methods described in any of the above embodiments.

[0057] The computer-readable medium of this embodiment includes permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device.

[0058] The computer instructions stored in the storage medium of the above embodiments are used to cause the computer to perform the methods described in any of the above embodiments, and have the beneficial effects of the corresponding method embodiments, which will not be repeated here.

[0059] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications, and variations of these embodiments will be apparent to those skilled in the art from the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may be used with the embodiments discussed.

[0060] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the claims of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A method for evaluating the deformation of a press-fit thin-walled cylinder liner during cold assembly, characterized in that, include: The set of cylinder bores to be evaluated in the engine under test is determined, and a unified measurement coordinate system corresponding to the set of cylinder bores to be evaluated is established to determine the zero position of the circumferential angle, the axial height reference, the cylinder bore numbering rules, and the cross-sectional correspondence. Collect the circumferential contour data of each cylinder bore in the set of cylinder bores to be evaluated, and construct a dataset covering all cylinder bores to be evaluated. The dataset includes a free state full cylinder bore contour dataset, a process cylinder head state full cylinder bore contour dataset, and a real cylinder head state full cylinder bore contour dataset. Data alignment and index calculation were performed on the full cylinder bore profile datasets under three states to obtain the circumference, cylindricity and Fourier order components of each state, each cylinder bore and each set axial section. A multi-index morphological envelope is constructed, which includes overall morphological index, local sensitive area index, order modal index, cylinder bore consistency index, and state difference index. Based on the multi-index morphological envelope, the cylinder bore assembly deformation evaluation and identification results are output.

2. The method according to claim 1, characterized in that: In the free state after the thin-walled cylinder liner has been pressed and the cylinder head has not been assembled, circumferential contour data is collected for each cylinder bore in the set of cylinder bores to be evaluated, forming a free state full cylinder bore contour dataset. Install the process cylinder head or process loading component to simulate the cylinder head assembly boundary on the machine body, and apply the cylinder head bolt preload according to the preset assembly process. Collect circumferential contour data for each cylinder hole in the same set of cylinder holes to be evaluated to form a full cylinder hole contour dataset of process cylinder head status. Remove the process cylinder head or process loading parts and install the real cylinder head. After applying the preload according to the assembly process corresponding to the real engine assembly, collect the circumferential contour data of each cylinder hole in the same set of cylinder holes to be evaluated to form a full cylinder hole contour dataset of the real cylinder head state.

3. The method according to claim 2, characterized in that: Preload includes torque loading, angular loading, axial force loading, or a combination thereof. The magnitude, number of loading stages, and loading sequence of the preload are determined based on the assembly process, process cylinder head structure, and actual cylinder head structure of the corresponding engine.

4. The method according to claim 1, characterized in that: The Fourier order components include at least a set order for identifying low-order long-wave distortion and high-order short-wave distortion, and the amplitude, phase and axial position of the corresponding order are extracted. The Fourier order components are obtained by decomposing the circumferential radial deviation function of each axial section into its order components. The circumferential radial deviation function is expressed as follows: In the formula, In assembly state. Number the cylinder bores. This refers to the axial position. It is a circumferential angle.

5. The method according to claim 1, characterized in that: The localized sensitive area includes at least one of the top sensitive area, the middle evaluation area, and the lower evaluation area near the cylinder head mating surface.

6. The method according to claim 1, characterized in that: The multi-index morphological envelope includes at least several of the following indices: full height cylindricity, maximum roundness of the set area, peak value of the second-order Fourier component and its axial position, peak value of the fourth-order Fourier component and its axial position, set order phase, consistency index between different cylinder bores under the same state, difference index between the process cylinder head state and the free state, difference index between the actual cylinder head state and the free state, and difference index between the actual cylinder head state and the process cylinder head state.

7. The method according to claim 1, characterized in that: The evaluation and identification results of cylinder bore assembly deformation include at least one of the following: dominant deformation order, sensitive axial position, sensitive cylinder bore, representative difference between process cylinder head state and actual cylinder head state, consistency between cylinder bores, and risk level.

8. A cold assembly deformation evaluation system for press-fit thin-walled cylinder liners, characterized in that, include: The cylinder bore set determination module is configured to determine the set of cylinder bores to be evaluated in the engine under test, and to establish a unified measurement coordinate system corresponding to the set of cylinder bores to be evaluated, so as to determine the zero position of the circumferential angle, the axial height reference, the cylinder bore numbering rules and the cross-sectional correspondence. The cylinder bore profile dataset construction module is configured to collect the circumferential profile data of each cylinder bore in the set of cylinder bores to be evaluated, and construct a dataset covering all cylinder bores to be evaluated. The dataset includes a free state full cylinder bore profile dataset, a process cylinder head state full cylinder bore profile dataset, and a real cylinder head state full cylinder bore profile dataset. The data processing module is configured to perform data alignment and index calculation on the full cylinder bore profile dataset under three states to obtain the circumference, cylindricity and Fourier order components of each state, each cylinder bore and each set axial section. The evaluation and identification output module is configured to construct a multi-index morphology envelope that includes overall morphology index, local sensitive area index, order modal index, cylinder bore consistency index, and state difference index, and output the cylinder bore assembly deformation evaluation and identification results based on the multi-index morphology envelope.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the program, implements the method as claimed in any one of claims 1-7.

10. A non-transitory computer-readable storage medium, characterized in that, in, The non-transitory computer-readable storage medium stores computer instructions for causing a computer to perform the method described in any one of claims 1-7.

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