Diesel engine diesel engine unit floating valve vibration isolation installation system and design method thereof

Abstract

The invention provides an internal combustion locomotive diesel engine unit floating valve vibration isolation installation system and a design method thereof. The installation system comprises a common base, a lower-layer vibration isolator, a middle raft frame, an upper-layer vibration isolator and a diesel generator set which are sequentially arranged from bottom to top. The upper portion of the common base is connected with the lower portion of the lower-layer vibration isolator, the upper portion of the lower-layer vibration isolator is connected with the lower portion of the middle raft frame, the upper portion of the middle raft frame is connected with the lower portion of the upper-layer vibration isolator, and the upper portion of the upper-layer vibration isolator is connected with the lower portion of the diesel generator set. The diesel generator set comprises a diesel engine and a generator, and the diesel engine and the generator are connected through an elastic coupling. The vibration of the diesel engine unit is localized, the vibration comfort of the cab of the diesel locomotive is improved, the vibration input magnitude of equipment on the locomotive is reduced, the reliability is improved, and the service life of the equipment is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of diesel-generator sets, and in particular to a floating valve vibration isolation installation system for a diesel-generator set of an internal combustion locomotive and a design method thereof. Background Art

[0002] The diesel generator set is the core power unit of the railway diesel locomotive and determines the power characteristics of the diesel locomotive. As the railway industry develops in the direction of high speed and heavy load, the output power of the diesel generator set continues to increase. As the most important vibration source of the diesel locomotive, the vibration energy input level of the diesel generator set to the locomotive body increases accordingly. The vibration generated by the diesel generator set is transmitted along the entire vehicle through the vehicle body chassis, which not only has an adverse effect on the comfort of the driver's cab, but also affects the normal operation, reliability and service life of the equipment on the vehicle.

[0003] At present, there are two types of installation for diesel locomotives: rigid installation and single-layer vibration isolator installation. Among them, rigid installation is to directly connect the diesel engine unit and the car body structure with bolts; when the diesel engine unit is working, all the vibration energy is transmitted to the car body structure in contact with it, and the input of vibration to the car body structure cannot be attenuated. The vibration is transmitted outward along the car body chassis, which has an adverse effect on the driver's cab and other on-board equipment. In addition, high processing accuracy is required for the contact surface, and high flatness is required for the installation contact surface. Each connection part needs to be finely processed, and the processing difficulty and cost are relatively high.

[0004] The installation of single-layer vibration isolators is to connect the diesel engine set to the car body structure through multiple vibration isolators. This connection form is a typical application of the single-layer vibration isolation system. The single-layer vibration isolation system can only achieve the vibration isolation effect when the excitation frequency is greater than the natural frequency of the system, and the vibration isolation effect is usually 10dB-20dB, which is difficult to meet the increasingly high technical requirements of diesel locomotives for vibration control. In particular, the vibration of the diesel engine set has harmonic phenomena, rich excitation frequency components, and the vibration transmission rate characteristic curve of the entire vibration isolation system has multiple peaks, which greatly reduces the vibration isolation effect of the single-layer vibration isolator installation. With the continuous improvement of the comfort of the diesel locomotive cab, the service life and reliability of the on-board equipment, it is imperative to reduce the vibration input of the diesel engine set to the car body structure. Summary of the invention

[0005] According to the above-mentioned rigid installation method, there is no attenuation of the vibration input of the vehicle body structure. Although the single-layer vibration isolator installation method has a vibration isolation capacity of 10dB-20dB, it cannot meet the increasing demand for vibration reduction in the industry. A floating valve vibration isolation installation system for a diesel engine set of a diesel locomotive and a design method thereof are provided. The present invention comprehensively improves the vibration isolation capacity through a floating valve vibration isolation installation system, localizes the vibration of the diesel engine set of a diesel locomotive, and ultimately achieves the goal of improving the vibration of the entire vehicle.

[0006] The technical means adopted by the present invention are as follows:

[0007] A floating valve vibration isolation installation system for a diesel engine set of a diesel locomotive, characterized in that it comprises: a common base, a lower vibration isolator, an intermediate raft frame, an upper vibration isolator and a diesel engine set arranged in sequence from bottom to top;

[0008] The upper part of the common base is connected to the lower part of the lower vibration isolator, the upper part of the lower vibration isolator is connected to the lower part of the middle raft frame, the upper part of the middle raft frame is connected to the lower part of the upper vibration isolator, and the upper part of the upper vibration isolator is connected to the lower part of the diesel generator set;

[0009] The diesel generator set comprises a diesel engine and a generator, and the diesel engine and the generator are connected via an elastic coupling.

[0010] Furthermore, the vibration transmission path of the installation system is as follows: the vibration generated by the diesel generator set is transmitted to the upper vibration isolator, the middle raft frame, the lower vibration isolator, the common base, and the vehicle body structure in sequence.

[0011] Furthermore, the middle raft frame is elastically connected to the upper vibration isolator, and the middle raft frame is elastically connected to the lower vibration isolator.

[0012] Furthermore, the number of the upper vibration isolators is greater than or equal to 6, and the number of the lower vibration isolators is greater than or equal to 4.

[0013] Furthermore, the upper vibration isolators are symmetrically arranged, and the lower vibration isolators are symmetrically arranged. The upper vibration isolators are arranged on the same horizontal plane, and the lower vibration isolators are arranged on the same horizontal plane.

[0014] Furthermore, the upper vibration isolator and the lower vibration isolator are air springs or rubber vibration isolators.

[0015] Furthermore, the bottom of the intermediate valve frame is a closed structure, damping material is applied inside the intermediate valve frame, and cement is poured in the intermediate valve frame.

[0016] The present invention also provides a method for designing a vibration isolation installation system for a diesel-generator set of a diesel locomotive, which is used to design any of the above-mentioned floating valve vibration isolation installation systems for a diesel-generator set of a diesel locomotive, and comprises the following steps:

[0017] S1. Obtain input parameters, wherein the input parameters include the mass and excitation frequency of the diesel generator set, the type of vibration isolator and its characteristic parameters, and technical parameter requirements and targets of vibration reduction effect;

[0018] S2. Determine the material selection, structural form, spatial dimensions and weight requirements of the intermediate raft according to the input parameters, and preliminarily determine the model, quantity and installation position of the upper and lower vibration isolators according to the load and frequency design requirements, thereby determining the preliminary floating valve vibration isolation system;

[0019] S3, perform a float valve system modal analysis on the preliminary float valve vibration isolation system. If the standard is met, execute S4; if the standard is not met, return to S2;

[0020] S4. Design the common base according to the overall design requirements of the diesel locomotive, and perform the third frequency margin calculation to determine whether the natural frequency of the common base can effectively avoid the excitation frequency of the diesel generator set. If it cannot be effectively avoided, modify the common base design until the natural frequency calculation meets the requirements and then execute S5.

[0021] S5, calculate the overall vibration characteristics of the installation system, estimate the vibration conditions of the main response points, and evaluate whether the vibration reduction effect meets the requirements. If not, return to S2; if satisfied, execute S6;

[0022] S6. Check whether the strength of the installation system under impact and vibration meets the requirements of relevant standards, and check whether the calculated overall structural strength meets the design requirements. If not, return to S2. If yes, output the installation system design plan.

[0023] Furthermore, S3 specifically includes the following steps:

[0024] S31, using numerical simulation means to calculate the modal frequency and vibration mode of the middle raft, and obtain the analysis results; performing the first frequency margin calculation to analyze whether there is a sufficient frequency margin between the natural frequency of the middle raft and the excitation frequency of the diesel generator set; if there is a sufficient frequency margin, the first condition is met;

[0025] S32. Based on the modal analysis results of the intermediate raft structure in S31, the modal frequency of the entire floating valve system is calculated;

[0026] S33, performing a second frequency margin calculation to analyze whether there is a sufficient frequency margin between the modal frequency of the float valve system and the excitation frequency of the diesel generator set; if there is a sufficient frequency margin, the second condition is met;

[0027] When the first condition and the second condition are met, execute S4, otherwise return to S2.

[0028] Among them, the frequency margin calculation formula is:

[0029]

[0030] Where, ω is the excitation frequency, ω n To calculate the natural frequency of the system.

[0031] Compared with the prior art, the present invention has the following advantages:

[0032] The present invention effectively isolates the vibration energy transmitted from the diesel engine set of the internal combustion locomotive to the vehicle body structure, and can achieve a 20-30dB vibration reduction effect.

[0033] The present invention localizes the vibration of the diesel generator set, improves the vibration comfort of the driver's cab of the diesel locomotive, reduces the vibration input level to the on-board equipment, and improves its reliability and service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0035] Figure 1 This is a structural diagram of the installation system of the present invention.

[0036] Figure 2 The present invention is a flow chart of the installation system design method.

[0037] In the figure: 1. diesel engine; 2. elastic coupling; 3. generator; 4. upper vibration isolator; 5. middle raft frame; 6. lower vibration isolator; 7. common base. DETAILED DESCRIPTION

[0038] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0039] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0041] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, the numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be clear that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0042] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention: the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0043] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below their position devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0044] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0045] like Figure 1 As shown, the present invention provides a floating valve vibration isolation installation system for a diesel locomotive diesel-generator set, which is composed of a common base 7, a lower vibration isolator 6, an intermediate raft 5, and an upper vibration isolator 4 from bottom to top. The diesel engine 1 and the generator 3 of the diesel locomotive are connected by an elastic coupling 2, and the diesel-generator set composed of the diesel engine 1 and the generator 3 is elastically connected to the intermediate raft 5 through the upper vibration isolator 4, and the intermediate raft 5 and the common base 7 are elastically connected through the lower vibration isolator 6. The vibration transmission path is diesel-generator set-upper vibration isolator-raft structure-lower vibration isolator-common base-car body structure. The entire installation structure attenuates the vibration input of the diesel-generator set to the car body structure on the transmission path through the joint action of the upper vibration isolator, the lower vibration isolator and the intermediate raft structure.

[0046] The vibration isolator is an important elastic element and damping element in the whole vibration isolation installation system, which can effectively attenuate the energy transmitted from the diesel engine unit to the common base. The vibration isolators are divided into two types according to different installation positions: upper vibration isolators 4 and lower vibration isolators 6. The number of upper vibration isolators is greater than or equal to 6, and the number of lower vibration isolators is greater than or equal to 4. In order to avoid coupled vibration, the layout of each layer of vibration isolators is symmetrical, and the vibration isolators on the same layer are arranged on the same horizontal plane. The selection of vibration isolators includes but is not limited to air springs, rubber vibration isolators and other types. Low-frequency vibration isolators are preferred, and they should be within their load-bearing range and effectively avoid the excitation frequency.

[0047] The middle valve frame 5 is an important mass element in the whole vibration isolation system. The inertial force of the mass element can effectively balance the excitation force generated by the diesel engine unit, thereby reducing the force transmission rate between the diesel engine unit and the common base 7, and achieving vibration reduction. The middle valve frame 5 is an integral metal material structural frame, which is welded and formed by typical frame components such as plates and beams. The bottom of the valve frame is a closed structure, which can be integrated with the waste oil collection function. In order to compensate for the poor damping performance of metal materials, damping materials are laid inside the frame to further enhance the vibration reduction effect. According to the calculation requirements of the weight of the mass element required for the entire vibration isolation system, cement of different masses is poured in the valve frame to meet the overall vibration reduction performance requirements.

[0048] The present invention also provides a design method for a floating valve vibration isolation installation system for a diesel locomotive diesel generator set. Figure 2 As shown, the following steps are included:

[0049] S1. Clarify the input parameters including: conduct characteristic analysis on diesel-generator sets of diesel locomotives, clarify the mass and excitation frequency of diesel-generator sets, clarify the types of existing vibration isolators and their characteristic parameters (load-bearing weight, natural frequency, vertical stiffness coefficient, damping ratio, etc.), and also clarify parameter requirements such as vibration reduction effect requirements.

[0050] S2. Determine the preliminary plan of the float valve system, including: determine the material selection, structural form, spatial dimensions, weight requirements, etc. of the intermediate raft according to the overall technical and other restrictions; preliminarily determine the model, quantity and installation position of the upper and lower isolators according to the load and frequency design requirements, thereby preliminarily determining the float valve vibration isolation system.

[0051] S3. Modal analysis of the floating valve system includes: first, using numerical simulation methods to calculate the modal frequency and vibration mode of the intermediate raft. And perform a frequency margin calculation to analyze whether there is sufficient frequency margin between the natural frequency of the intermediate raft and the excitation frequency of the diesel generator set. Then, based on the modal analysis results of the intermediate raft structure, calculate the modal frequency of the entire floating valve system. Perform another frequency margin calculation to analyze whether there is sufficient frequency margin between the frequency of the floating valve system and the excitation frequency of the diesel generator set. Among them, the vibration isolation frequency margin calculation formula is:

[0052]

[0053] (ω,ω n Refers to the excitation frequency and the natural frequency of the system respectively). If not satisfied, return to S2; if satisfied, enter S4.

[0054] S4, common base design includes: designing the common base according to the overall design requirements of the diesel locomotive. The design requirements of the common base are that the input impedance is as large as possible, and the natural frequency and strength are calculated at the same time. The calculation formula is the same as the S3 formula. It is required that its natural frequency should also effectively avoid the excitation frequency of the diesel generator set, and the strength should meet the design requirements. If not, the common base design needs to be modified until the natural frequency calculation requirements are met. If they are met, enter S5.

[0055] S5. Analysis of vibration characteristics of the installation system includes: calculating the overall vibration characteristics of the installation system consisting of the diesel generator set, the upper vibration isolator, the middle raft, the lower vibration isolator, and the common base, estimating the vibration conditions of the main response points, and evaluating whether the vibration reduction effect meets the requirements. If not satisfied, return to S2, if satisfied, enter S6.

[0056] S6, strength verification calculation includes: verifying whether the strength of the diesel engine installation system under impact and vibration meets the requirements of relevant standards, and verifying whether the overall structural strength meets the design requirements. If not, return to S2, if yes, enter S7.

[0057] S7. Determine the final solution, including: if all the above methods are passed, an installation system solution is formed and the design method is completed.

[0058] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A floating valve vibration isolation installation system for a diesel locomotive diesel generator set, characterized in that: include: The common base, lower vibration isolator, middle raft frame, upper vibration isolator and diesel generator set are arranged in sequence from bottom to top; The upper part of the common base is connected to the lower part of the lower vibration isolator, the upper part of the lower vibration isolator is connected to the lower part of the middle raft frame, the upper part of the middle raft frame is connected to the lower part of the upper vibration isolator, and the upper part of the upper vibration isolator is connected to the lower part of the diesel generator set; The diesel generator set comprises a diesel engine and a generator, and the diesel engine and the generator are connected via an elastic coupling.

2. The diesel locomotive diesel generator set floating valve vibration isolation installation system according to claim 1, characterized in that: The vibration transmission path of the installation system is as follows: the vibration generated by the diesel engine unit is transmitted to the upper vibration isolator, the middle raft frame, the lower vibration isolator, the common base, and the vehicle body structure in sequence.

3. The diesel locomotive diesel generator set floating valve vibration isolation installation system according to claim 1, characterized in that: The middle raft frame is elastically connected to the upper vibration isolator, and the middle raft frame is elastically connected to the lower vibration isolator.

4. The diesel locomotive diesel generator set floating valve vibration isolation installation system according to claim 1, characterized in that: The number of the upper vibration isolators is greater than or equal to 6, and the number of the lower vibration isolators is greater than or equal to 4.

5. The floating valve vibration isolation installation system for diesel locomotive diesel generator set according to claim 1, characterized in that: The upper vibration isolators are arranged symmetrically, and the lower vibration isolators are arranged symmetrically. The upper vibration isolators are arranged on the same horizontal plane, and the lower vibration isolators are arranged on the same horizontal plane.

6. The diesel locomotive diesel generator set floating valve vibration isolation installation system according to claim 1, characterized in that: The upper vibration isolator and the lower vibration isolator are air springs or rubber vibration isolators.

7. The floating valve vibration isolation installation system for diesel locomotive diesel generator set according to claim 1, characterized in that: The bottom of the intermediate valve frame is a closed structure, the interior of the intermediate valve frame is provided with damping material, and cement is poured in the intermediate valve frame.

8. A design method for a floating valve vibration isolation installation system for a diesel locomotive diesel generator set, characterized in that: The design of the vibration isolation installation system for the floating valve of a diesel engine set of a diesel locomotive according to any one of claims 1 to 7 comprises the following steps: S1. Obtain input parameters, wherein the input parameters include the mass and excitation frequency of the diesel generator set, the type of vibration isolator and its characteristic parameters, and technical parameter requirements and targets of vibration reduction effect; S2. Determine the material selection, structural form, spatial dimensions and weight requirements of the intermediate raft according to the input parameters, and preliminarily determine the model, quantity and installation position of the upper and lower vibration isolators according to the load and frequency design requirements, thereby determining the preliminary floating valve vibration isolation system; S3, perform a float valve system modal analysis on the preliminary float valve vibration isolation system. If the standard is met, execute S4; if the standard is not met, return to S2; S4. Design the common base according to the overall design requirements of the diesel locomotive, and perform the third frequency margin calculation to determine whether the natural frequency of the common base can effectively avoid the excitation frequency of the diesel generator set. If it cannot be effectively avoided, modify the common base design until the natural frequency calculation meets the requirements and then execute S5. S5, calculate the overall vibration characteristics of the installation system, estimate the vibration conditions of the main response points, and evaluate whether the vibration reduction effect meets the requirements. If not, return to S2; if satisfied, execute S6; S6. Check whether the strength of the installation system under impact and vibration meets the requirements of relevant standards, and check whether the calculated overall structural strength meets the design requirements. If not, return to S2. If yes, output the installation system design plan.

9. The design method of the floating valve vibration isolation installation system for a diesel locomotive diesel generator set according to claim 1 is characterized in that: S3 specifically includes the following steps: S31, using numerical simulation means to calculate the modal frequency and vibration mode of the middle raft, and obtain the analysis results; performing the first frequency margin calculation to analyze whether there is a sufficient frequency margin between the natural frequency of the middle raft and the excitation frequency of the diesel generator set; if there is a sufficient frequency margin, the first condition is met; S32. Based on the modal analysis results of the intermediate raft structure in S31, the modal frequency of the entire floating valve system is calculated; S33, performing a second frequency margin calculation to analyze whether there is a sufficient frequency margin between the modal frequency of the float valve system and the excitation frequency of the diesel generator set; if there is a sufficient frequency margin, the second condition is met; When the first condition and the second condition are met, execute S4, otherwise return to S2. Among them, the frequency margin calculation formula is: Where, ω is the excitation frequency, ω n To calculate the natural frequency of the system.

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