Planetary mechanism transmission efficiency calculation method

Abstract

A planetary mechanism transmission efficiency calculation method mainly comprises the steps of obtaining calculation data of a planetary mechanism according to the structure of the planetary mechanism; calculating transmission ratios of power flow branches in conversion gear trains corresponding to all planetary gear trains in the planetary mechanism; calculating the transmission efficiency of the power flow branches in the conversion gear trains corresponding to all the planetary gear trains in the planetary mechanism, and calculating the transmission efficiency of all the planetary gear trains in the planetary mechanism; and calculating the transmission efficiency of the planetary mechanism. The method can quickly, simply and conveniently calculate the transmission efficiency of the planetary mechanism, and is high in calculation efficiency and accuracy.

Description

Technical Field

[0001] The invention relates to the technical field of gear train transmission systems, and in particular to a method for calculating the transmission efficiency of a planetary mechanism. Background Art

[0002] The transmission system is the core component of the propulsion system. It transmits the engine power to the driving wheel. Through the transmission of power, the expansion of torque and speed characteristics, it realizes the driving functions of the tank such as forward, backward, climbing, jumping trenches, braking, and steering. Planetary mechanisms are widely used in the design of heavy-duty vehicle transmission systems due to their high load capacity and stiffness. Transmission efficiency is an important indicator to measure the performance of the transmission system. Therefore, the research on the transmission efficiency of planetary mechanisms has important engineering significance.

[0003] Although there are many methods for calculating the transmission efficiency of planetary gear trains, most of the current methods are rather cumbersome and complicated. Especially for planetary mechanisms, there is a lack of systematic and effective methods for calculating the transmission efficiency. Summary of the invention

[0004] The present disclosure provides a method for calculating the transmission efficiency of a planetary mechanism, which can greatly improve the calculation speed and accuracy of the transmission efficiency of the planetary mechanism.

[0005] The method for calculating the transmission efficiency of a planetary mechanism provided by the present disclosure comprises the following steps:

[0006] S1, obtain the calculation data of the planetary mechanism;

[0007] S2, calculating the transmission ratios of the conversion gear trains corresponding to all the planetary gear trains in the planetary mechanism;

[0008] S3, calculating the transmission efficiency of the conversion gear trains corresponding to all the planetary gear trains in the planetary mechanism;

[0009] S4, calculate the transmission efficiency of the planetary mechanism.

[0010] Furthermore, in step S1, the calculation data obtained includes:

[0011] The number of teeth of the central wheel, the number of teeth of each planetary wheel, and the number of teeth of the ring gear included in each planetary gear train in the planetary mechanism;

[0012] And the transmission efficiency of each power flow branch in the conversion gear train corresponding to each planetary gear train.

[0013] Furthermore, in step S2, the transmission ratio calculation formula of the conversion gear train corresponding to each planetary gear train is:

[0014]

[0015] In the formula, is the transmission ratio corresponding to the planetary gear train, z a is the number of teeth of the central wheel in the planetary gear system, z b is the number of teeth on the ring gear in the planetary gear system.

[0016] Furthermore, the specific method of step S3 includes:

[0017] When the transmission ratio of the planetary gear train corresponding to the conversion gear train or The transmission efficiency calculation formula of the planetary gear train is:

[0018]

[0019] Where η H is the transmission efficiency of the planetary gear train, is the transmission ratio of the conversion gear train corresponding to the planetary gear train, n is the number of planetary gears in the planetary gear train, is the transmission efficiency of the jth power flow branch in the conversion gear train corresponding to the planetary gear train;

[0020] When the transmission ratio of the planetary gear train corresponding to the conversion gear train The transmission efficiency calculation formula of the planetary gear train is:

[0021]

[0022] Where η H is the transmission efficiency of the planetary gear train, is the transmission ratio of the conversion gear train corresponding to the planetary gear train, n is the number of planetary gears in the planetary gear train, It is the transmission efficiency of the jth power flow branch in the conversion gear train corresponding to the planetary gear train.

[0023] Furthermore, the specific method of step S4 includes:

[0024] The transmission efficiency of the planetary mechanism=the product of the transmission efficiencies of the conversion gear trains corresponding to all the planetary gear trains in the planetary mechanism obtained in step S3.

[0025] Compared with the prior art, the beneficial effects of the present invention are: (1) according to the structure of the planetary mechanism, by calculating the transmission ratio of the power flow branch in the conversion gear train corresponding to all the planetary gear trains in the planetary mechanism and calculating the transmission efficiency of the power flow branch in the conversion gear train corresponding to all the planetary gear trains in the planetary mechanism, the transmission efficiency of all the planetary gear trains in the planetary mechanism is obtained, and then the transmission efficiency of the entire planetary mechanism is obtained; (2) the transmission efficiency of the planetary mechanism can be calculated quickly and easily, and the calculation efficiency and accuracy are high; (3) it has good versatility and is suitable for planetary transmission mechanisms of various structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and other objects, features and advantages of the present disclosure will become more apparent through a more detailed description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present disclosure.

[0027] Figure 1 is a flow chart of a method for calculating transmission efficiency of a planetary mechanism according to the present disclosure;

[0028] Figure 2 This is a transmission principle diagram of a planetary mechanism showing an exemplary embodiment, wherein: 1 is center wheel one, 2 is planet wheel one, 3 is ring gear one, A is planet carrier A, 4 is center wheel two, 5 is planet wheel two, 6 is ring gear two, and B is planet carrier B. DETAILED DESCRIPTION

[0029] The preferred embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the preferred embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0030] The present disclosure provides a method for calculating the transmission efficiency of a planetary mechanism. Figure 1 As shown, it mainly includes the following steps:

[0031] S1, obtain the calculation data of the planetary mechanism;

[0032] S2, calculating the transmission ratios of the conversion gear trains corresponding to all the planetary gear trains in the planetary mechanism;

[0033] S3, calculating the transmission efficiency of the conversion gear trains corresponding to all the planetary gear trains in the planetary mechanism;

[0034] S4, calculate the transmission efficiency of the planetary mechanism.

[0035] In an exemplary embodiment, the structure of the planetary mechanism is as follows Figure 2 As shown, it mainly includes:

[0036] Center gear 1, planet gear 1j (j=1,…,n1), ring gear 1, planet carrier A,

[0037] Center gear 2, planet gear 2j (j=1,…,n2), ring gear 2, planet carrier B,

[0038] The center gear 1, the planetary gear 1j (j=1,…,n1), the ring gear 1, the planet carrier A, constitute the planetary gear train 1,

[0039] The center gear 2, the planet gear 2j (j=1,…,n2), the ring gear 2, and the planet carrier B constitute the planet gear train 2.

[0040] The center gear 1, the planet gear 1j (j=1,…,n1), the ring gear 1, and the planet carrier A form n1 power flow branches.

[0041] The center gear 2, the planet gear 2j (j=1,…,n2), the ring gear 2, and the planet carrier B form n2 power flow branches.

[0042] The planet carrier A and the center gear 2 are fixedly connected on the same shaft, the ring gear 1 and the ring gear 2 are fixedly connected to the frame respectively, the center gear 1 is the power input end, and the planet carrier B is the power output end.

[0043] According to the present disclosure, the method for calculating the transmission efficiency of the planetary mechanism comprises the following steps:

[0044] Step 1: Obtain the calculation data of the planetary mechanism, mainly including:

[0045] The number of teeth of the center gear 1 is z1, the number of teeth of the planet gear 1 j (j = 1, ..., n1) is z2, the number of teeth of the ring gear 1 is z3,

[0046] The number of teeth of the center gear 2 is z4, the number of teeth of the planet gear 2 j (j = 1, ..., n2) is z5, the number of teeth of the ring gear 2 is z6,

[0047] Transmission efficiency of power flow splitting in a planetary gear train and a corresponding conversion gear train

[0048] Transmission efficiency of power flow split in the conversion gear train corresponding to the second planetary gear train

[0049] Step 2: Calculate the transmission ratio of the power flow branch in the conversion gear train corresponding to all the planetary gear trains in the planetary mechanism. The specific process is:

[0050] The transmission ratio calculation formula of the power flow branch in the conversion gear train corresponding to the planetary gear train is used to calculate the transmission ratio of the conversion gear train corresponding to the planetary gear train. Transmission ratio of the conversion gear train corresponding to the second planetary gear train

[0051] The transmission ratio calculation formula of the conversion gear train corresponding to the planetary gear train is:

[0052]

[0053] In the formula, is the transmission ratio corresponding to the planetary gear train, z b is the number of teeth on the ring gear in the planetary gear train, z a is the number of teeth on the center wheel in the planetary gear train.

[0054] Step 3: Calculate the transmission efficiency of the conversion gear trains corresponding to all the planetary gear trains in the planetary mechanism. The specific process is:

[0055] According to the transmission ratio of the conversion gear train corresponding to all planetary gear trains Reasonably select the transmission efficiency calculation formula of the planetary gear train, and use the transmission efficiency calculation formula of the planetary gear train to calculate the transmission efficiency η of the power flow branch in the conversion gear train corresponding to the planetary gear train. A , the transmission efficiency η of the power flow branch in the conversion gear train corresponding to the second planetary gear train B :

[0056] When the transmission ratio of the planetary gear train corresponding to the conversion gear train or The transmission efficiency calculation formula of the planetary gear train is:

[0057]

[0058] Where η H is the transmission efficiency of the planetary gear train, is the transmission ratio of the conversion gear train corresponding to the planetary gear train, The transmission efficiency of the power flow split in the conversion gear train corresponding to the planetary gear train;

[0059] When the transmission ratio of the planetary gear train corresponding to the conversion gear train The transmission efficiency calculation formula of the planetary gear train is:

[0060]

[0061] Where η H is the transmission efficiency of the planetary gear train, is the transmission ratio of the conversion gear train corresponding to the planetary gear train, It is the transmission efficiency of the power flow branch in the conversion gear train corresponding to the planetary gear train.

[0062] Step 4:

[0063] The transmission efficiency of the planetary mechanism is calculated by the transmission efficiency calculation formula of the planetary mechanism shown in formula (4): c :

[0064] η c =η A η B (4);

[0065] Where η c is the transmission efficiency of the planetary mechanism, η A is the transmission efficiency of the planetary gear train, η B is the transmission efficiency of planetary gear train 2.

[0066] Application Examples

[0067] Step 1: The calculated data obtained are shown in Table 1.

[0068] Table 1

[0069]

[0070] Among them, there are four planetary gears in the planetary gear train 1 (center gear 1, planetary gear 1, ring gear 1), and there are two planetary gears in the planetary gear train 2 (center gear 2, planetary gear 2, ring gear 2). The power split transmission efficiency is:

[0071]

[0072] Step 2:

[0073] Using the number of teeth z1 of the center gear 1 and the number of teeth z2 of the ring gear 1 in step 1, the transmission ratio calculation formula of the power flow branch in the conversion gear train corresponding to the planetary gear train shown in formula (5) is used to calculate the transmission ratio of the conversion gear train corresponding to the planetary gear train 1: Transmission ratio of the conversion gear train corresponding to the second planetary gear train The results are shown in Table 2.

[0074]

[0075] In the formula, is the transmission ratio of the conversion gear train corresponding to the planetary gear train, z a is the number of teeth of the central wheel in the planetary gear train, z b is the number of teeth on the ring gear in the planetary gear train.

[0076] Table 2

[0077]

[0078] Step 3:

[0079] According to the transmission ratio of the conversion gear train corresponding to the planetary gear train calculated in step 2, the transmission efficiency of the power flow branch in the conversion gear train corresponding to the planetary gear train in step 1 is used. The transmission ratio of the power flow split in the conversion gear train corresponding to the planetary gear train calculated in step 2 The transmission efficiency calculation formula of the planetary gear train shown in (6) is used to calculate the transmission efficiency η of the power flow branch in the conversion gear train corresponding to the planetary gear train. A ;

[0080] The transmission efficiency of the power flow split in the conversion gear train corresponding to the planetary gear train 2 in step 1 (j=1,…,n2), the transmission ratio of the power flow branch in the conversion gear train corresponding to the second planetary gear train calculated in step 2 The transmission efficiency η of the power flow split in the conversion gear train corresponding to the planetary gear train 2 shown in (6) B , the results are shown in Table 3.

[0081]

[0082] Where η is the transmission efficiency of the planetary gear train, is the transmission ratio of the conversion gear train corresponding to the planetary gear train, It is the transmission efficiency of the conversion gear train corresponding to the planetary gear train.

[0083] Table 3

[0084] <![CDATA[The transmission efficiency η of the planetary gear train A A > <![CDATA[The transmission efficiency η of the planetary gear train B B > 0.885 0.873

[0085] Step 4: Use the transmission efficiency η of the planetary gear train 1 calculated in step 3 A 、Transmission efficiency η of planetary gear train 2 B The transmission efficiency η of the planetary mechanism is calculated by the transmission efficiency calculation formula of the planetary mechanism shown in formula (7): c , the results are shown in Table 5.

[0086] η c =η A η B (7);

[0087] Where η c is the transmission efficiency of the planetary mechanism, η A is the transmission efficiency of the planetary gear train A, η B is the transmission efficiency of planetary gear train B.

[0088] Table 5

[0089] <![CDATA[Transmission efficiency η of the planetary mechanism c > 0.772

[0090] This embodiment can quickly and easily calculate the transmission efficiency of the planetary mechanism, and has high calculation efficiency and accuracy.

[0091] The above technical scheme is only an exemplary embodiment of the present invention. For those skilled in the art, it is easy to make various types of improvements or modifications based on the application methods and principles disclosed in the present invention, and it is not limited to the method described in the above specific embodiment of the present invention. Therefore, the method described above is only preferred and does not have a restrictive meaning.

Claims

1. A method for calculating the transmission efficiency of a planetary mechanism, comprising the following steps: S1, obtain the calculation data of the planetary mechanism; S2, calculating the transmission ratios of the conversion gear trains corresponding to all the planetary gear trains in the planetary mechanism; S3, calculating the transmission efficiency of the conversion gear trains corresponding to all the planetary gear trains in the planetary mechanism; S4, calculate the transmission efficiency of the planetary mechanism.

2. The method according to claim 1, characterized in that In step S1, the calculation data obtained includes: The number of teeth of the central wheel, the number of teeth of each planetary wheel, and the number of teeth of the ring gear included in each planetary gear train in the planetary mechanism; And the transmission efficiency of each power flow branch in the conversion gear train corresponding to each planetary gear train.

3. The method according to claim 1 or 2, characterized in that: In step S2, the transmission ratio calculation formula of the conversion gear train corresponding to each planetary gear train is: In the formula, is the transmission ratio corresponding to the planetary gear train, z a is the number of teeth of the central wheel in the planetary gear system, z b is the number of teeth on the ring gear in the planetary gear system.

4. The method according to claim 1 or 2, characterized in that: The specific method of step S3 includes: When the transmission ratio of the planetary gear train corresponding to the conversion gear train or The transmission efficiency calculation formula of the planetary gear train is: Where η H is the transmission efficiency of the planetary gear train, is the transmission ratio of the conversion gear train corresponding to the planetary gear train, n is the number of planetary gears in the planetary gear train, is the transmission efficiency of the jth power flow branch in the conversion gear train corresponding to the planetary gear train; When the transmission ratio of the planetary gear train corresponding to the conversion gear train The transmission efficiency calculation formula of the planetary gear train is: Where η H is the transmission efficiency of the planetary gear train, is the transmission ratio of the conversion gear train corresponding to the planetary gear train, n is the number of planetary gears in the planetary gear train, It is the transmission efficiency of the jth power flow branch in the conversion gear train corresponding to the planetary gear train.

5. The method according to claim 1 or 2, characterized in that: The specific method of step S4 includes: The transmission efficiency of the planetary mechanism=the product of the transmission efficiencies of the conversion gear trains corresponding to all the planetary gear trains in the planetary mechanism obtained in step S3.

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