A method for checking the structural strength of a transmission shaft in a turbine starter

Abstract

The present invention discloses a method for checking the structural strength of a transmission shaft in a turbine starter. For the inner and outer transmission shaft structural components in the turbine starter, the strength checking calculation is converted from steady-state transmission to transient start-up, extended from the wedging section to the non-wedging section, and at the same time, the objectively existing contact plastic deformation and shakedown analysis checking in the wedging section are added, which can deepen the checking calculation method for the contact surface strength and overall structural strength of the main and driven transmission shafts of the clutch, making the forward design and checking of the transmission shaft and the turbine starter more accurate and comprehensive.

Description

Technical Field

[0001] The present invention relates to the field of clutches, and particularly to a method for checking the structural strength of a drive shaft in a turbine starter, which is mainly applied to the main and driven drive shafts that cooperate with a diagonal support clutch in a turbine starter. Background Art

[0002] The diagonal support clutch is installed between the main and driven drive shafts, and the torque of the driving shaft is unidirectionally transmitted to the driven shaft through the diagonal support clutch. The structure of the diagonal support clutch is similar to that of a rolling bearing, and generally consists of diagonal support blocks, a cage, springs, etc. The inner and outer drive shafts are frictionally wedged through the diagonal support clutch to transmit power (i.e., torque), so the structural strength of the drive shaft is closely related to the diagonal support clutch. To date, for the design and calculation check of the drive shaft, domestic and foreign scholars or research institutions still mainly focus on the contact stress between the diagonal support clutch and the inner and outer shafts during steady-state transmission, as well as the circumferential stress of the inner and outer shafts.

[0003] Different from the conventional drive shaft mainly for steady-state transmission, the service conditions of the turbine starter are mainly short-time and frequent start-up and acceleration states. Moreover, the impact load during start-up transient is also greater than the rated load during steady-state transmission. Therefore, the design check of the drive shaft should be oriented to the load under the start-up and acceleration state. In addition, there are plastic deformation and structural stability in the inner and outer drive shafts of the wedging section, and a single circumferential stress cannot accurately express the internal stress. Finally, the non-wedging section of the drive shaft only bears torsional shear loads, and a corresponding check calculation model should be established. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for checking the structural strength of a drive shaft in a turbine starter for the defects involved in the background art. For the inner and outer drive shaft structural parts in the turbine starter, the strength check calculation is converted from steady-state transmission to transient start-up, extended from the wedging section to the non-wedging section, and at the same time, the objectively existing contact plastic deformation and stability analysis check in the wedging section are added, which can deepen the check calculation method of the contact surface strength and overall structural strength of the main and driven drive shafts of the clutch, making the forward design and check of the drive shaft and the turbine starter more accurate and comprehensive.

[0005] The present invention adopts the following technical solutions to solve the above technical problems:

[0006] A method for checking the structural strength of a drive shaft in a turbine starter, the drive shaft includes a driving shaft, a driven shaft and a diagonal support clutch, and through the frictional wedging of the diagonal support clutch, the driving shaft and the driven shaft realize power transmission. The structural strength check method includes the following steps:

[0007] Step 1), through the actual measurement and output of the load spectrum, obtain the maximum torque T of the drive shaft at the start-up transient t0; let the inner and outer radii of the driving shaft be R o 、Rod The inner and outer radii of the driven shaft are R id and R i respectively; the distance between the inner and outer raceways is J; the length of the swash block in the swash plate clutch is l, and the radii of the inner and outer profile surfaces are r i and r o respectively; the wedge angles formed by the swash plate clutch with the driving shaft and the driven shaft are set as W and V respectively; the number of swash blocks in the swash plate clutch is n;

[0008] Step 2), perform shakedown check on the contact surfaces of the driving shaft, the driven shaft and the swash plate clutch:

[0009] Step 2.1), as the load T increases, the swash plate clutch contacts the raceway surfaces of the driving shaft and the driven shaft and gradually rotates counterclockwise. The normal load N o of the driving shaft and the normal load N i of the driven shaft are:

[0010]

[0011] Step 2.2), the contact between the arc surface of the swash plate clutch and the raceways of the driving shaft and the driven shaft is line contact. Under frequent contact impacts, plastic deformation will occur on the raceway surfaces of the swash plate clutch and the driving shaft and the driven shaft, the material in the contact area is strengthened, the yield limit increases, and the structure enters the shakedown state; establish the calculation and discrimination formulas for the contact shakedown of the swash plate clutch with the driving shaft and the driven shaft:

[0012]

[0013] where C es_o and C es_i are the contact shakedown coefficients of the driving shaft and the driven shaft respectively; E o and E s and E i are the elastic moduli of the driving shaft, the swash block and the driven shaft respectively; ν o and ν s and ν i are the Poisson's ratios of the driving shaft, the swash block and the driven shaft respectively; σ so and σ si are the contact yield stresses of the driving shaft and the driven shaft respectively;

[0014] Step 2.3), perform structural shakedown check and discrimination according to C es_o and C es_i :

[0015] Step 2.3.1), when C es_o ∈(10.30, 13.37], plastic deformation occurs on the contact surface between the driving shaft and the swash plate clutch, and the structure tends to be shakedown after cyclic loading;

[0016] Step 2.3.2), when C es_o ≤10.30, the contact surface of the driving shaft is in the elastic deformation state, and it is difficult to produce plastic shakedown;

[0017] Step 2.3.3), when C es_o >13.37, large plastic deformation occurs on the contact surface of the driving shaft, and cyclic loading will lead to the accumulation of plastic deformation and cause failure;

[0018] Step 2.3.4), when C es_i ∈(10.30, 13.37], plastic deformation occurs on the contact surface between the driven shaft and the swashplate clutch, and the structure tends to be stable after cyclic loading;

[0019] Step 2.3.5), when C es_i ≤10.30, the contact surface of the driven shaft is in the elastic deformation state, and it is difficult to produce plastic shakedown;

[0020] Step 2.3.6), when C es_i >13.37, large plastic deformation occurs on the contact surface of the driven shaft, and cyclic loading will lead to the accumulation of plastic deformation and cause surface failure;

[0021] Step 3), perform overall structural strength check on the driving shaft and the driven shaft:

[0022] Step 3.1), perform iterative calculation according to the following cycle, and obtain the updated W and V after reaching stability:

[0023]

[0024]

[0025]

[0026] V = W + ψ

[0027]

[0028]

[0029]

[0030]

[0031]

[0032] In the formula, are the dynamically changing inner arc radius of the driving shaft and the outer arc radius of the driven shaft; They are respectively the outer arc radius and inner arc radius of the dynamically changing stay block; Ω is the rotation angle of the dynamically changing stay block; α is the dynamically changing central angle; ψ is the included angle of the arc centers of the dynamically changing stay block; The initial values of o are R i , R o , r i , r

[0033] C o , C i , C s are respectively the influence coefficients of the driving shaft, the driven shaft and the stay block; b is the width of the stay block;

[0034] C1, C2, C3 are respectively the Hertz influence coefficient, the Hertz influence coefficient between the stay block and the driving shaft, and the Hertz influence coefficient between the stay block and the driven shaft;

[0035] Δ ce is the radial displacement of the driving shaft caused by centrifugal force,

[0036] ρ o is the material density of the driving shaft, n o is the rotational speed during the clutch engagement drive;

[0037] Step 3.2), calculate the maximum combined stress σ so_max of the driving shaft and the maximum combined stress σ si_max of the driven shaft according to the following formula:

[0038]

[0039] Step 3.3), compare σ so_max and σ 0.2(so) and compare σ si_max and σ 0.2(si) σ 0.2(so) , σ 0.2(si) are respectively the overall yield stresses of the driving shaft and the transmission shaft;

[0040] Step 3.3.1), when σ so_max ≤σ 0.2(so) and σ si_max ≤σ 0.2(si) , the driving shaft and the driven shaft are stably engaged in transmission and no structural damage occurs;

[0041] Step 3.3.2), when σ so_max ≥σ 0.2(so) or σsi_max ≥σ 0.2(si) When it is ≥σ, the driving shaft and the driven shaft will break during transmission;

[0042] Step 4), check the shear strength of the non-wedged sections of the driving shaft and the driven shaft:

[0043] Step 4.1), calculate the maximum shear stress τ of the driving shaft according to the following formula o_max and the maximum shear stress τ of the driven shaft i_max :

[0044]

[0045] Step 4.2), compare τ o_max with [τ0], and compare τ i_max with [τ i , [τ0], [τ i are the allowable shear stresses of the driving shaft and the driven shaft respectively:

[0046] Step 4.2.1), when τ o_max ≤[τ0] and τ i_max ≤[τ i , the driving shaft and the driven shaft are stably wedged and transmitted without structural damage;

[0047] Step 4.2.2), when τ o_max ≥[τ0] or τ i_max ≥[τ i , the driving shaft and the driven shaft will undergo shear fracture during transmission.

[0048] Compared with the traditional Hertz contact stress check and circumferential stress check based on steady-state transmission, the calculation and check method of the present invention is more specific, scientific and accurate, mainly manifested in:

[0049] (1) Switch the steady-state transmission check to the transient transmission check with a larger load, making the calculation more accurate;

[0050] (2) The plastic deformation and structural stability of the contact surface are beneficial to improving the yield strength of the contact surface. Adding the stability analysis and check is more scientific and beneficial to extending the overall service life;

[0051] (3) The combined stress more accurately reflects the load on the structure of the wedged sections of the driving shaft and the driven shaft, making the check more effective;

[0052] (4) Expand the check range from the wedged section to the non-wedged section, making the structural strength check of the transmission shaft more comprehensive. Description of the Drawings

[0053] Figure 1It is a schematic diagram of the torque change from transient start to steady-state transmission;

[0054] Figure 2 It is a schematic diagram of the structural parameters of the diagonal support clutch and the two-axis raceway;

[0055] Figure 3 It is a schematic diagram of the structure of the transmission shaft in the present invention. Detailed implementation manners

[0056] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings:

[0057] The present invention can be implemented in many different forms and should not be considered limited to the embodiments described herein. On the contrary, these embodiments are provided so that this disclosure is thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. In the drawings, components are enlarged for clarity.

[0058] As Figure 3 shown, the transmission shaft assembly includes a driving shaft, a driven shaft, and a diagonal support clutch. Through the frictional engagement of the diagonal support clutch, the transmission shaft realizes power transmission. By measuring and outputting the load spectrum, the maximum torque at the start transient t0 and the torque at the steady state t e are respectively set as T and T′, and it should be T > T′, as Figure 1 shown.

[0059] As Figure 2 shown, let the inner and outer arc radii of the driving shaft (outer shaft) be R o , R od , the inner and outer arc radii of the driven shaft (inner shaft) be R id , R i , and the distance between the inner and outer raceways be J. The length of the diagonal support block in the diagonal support clutch is l, and the radii of the inner and outer profiles are r i , r o ; the wedge angles formed by the diagonal support block with the driving shaft and the driven shaft are respectively set as W and V; the number of diagonal support blocks in the diagonal support clutch is n.

[0060] A. Surface contact check and overall strength check of the wedging sections of the driving shaft and the driven shaft

[0061] As the load T increases, the raceway surfaces of the diagonal support clutch and the two shafts come into contact and gradually rotate counterclockwise. Since the raceway surface and the diagonal support clutch are in high pair contact, relatively large normal loads and contact stresses are generated.

[0062] First, regarding the surface stability check of the contact surfaces of the driving shaft, the driven shaft, and the diagonal support clutch. The normal load N o of the driving shaft and the normal load N i of the driven shaft are:

[0063]

[0064] The contact between the arc surface of the diagonal brace clutch and the raceways of the driving shaft and the driven shaft is a line contact. Under frequent contact impacts, certain plastic deformations will occur on the raceway surfaces of the diagonal brace clutch, the driving shaft, and the driven shaft. The material in the contact area is strengthened, the yield limit increases, and the structure enters a shakedown state. Since the diagonal brace clutch has a high similarity to a cylindrical roller bearing in terms of structural characteristics and contact type, the shakedown principle of roller bearing contact is used for reference to establish the calculation and discrimination formulas for the shakedown of the contact between the diagonal brace clutch and the driving shaft and the driven shaft:

[0065]

[0066] Among them, E o 、E s 、E i are the elastic moduli of the driving shaft, the diagonal brace block, and the driven shaft respectively; ν o 、ν s 、ν i are the Poisson's ratios of the driving shaft, the diagonal brace block, and the driven shaft respectively; σ so 、σ si are the contact yield stresses of the driving shaft and the driven shaft respectively.

[0067] Through multiple experimental tests, the following structural shakedown checking and discrimination methods for the contact surfaces of the driving shaft, the driven shaft, and the diagonal brace clutch are obtained:

[0068] (1) When C es_o ∈(10.30, 13.37], plastic deformation occurs on the contact surface between the driving shaft and the diagonal brace clutch, and the structure tends to shakedown after cyclic loading;

[0069] (2) When C es_o ≤10.30, the contact surface of the driving shaft is in an elastic deformation state, and it is difficult to generate plastic shakedown;

[0070] (3) When C es_o >13.37, large plastic deformation occurs on the contact surface of the driving shaft, and cyclic loading will lead to the accumulation of plastic deformation and cause failure;

[0071] (4) When C es_i ∈(10.30, 13.37], plastic deformation occurs on the contact surface between the driven shaft and the diagonal brace clutch, and the structure tends to shakedown after cyclic loading;

[0072] (5) When C es_i ≤10.30, the contact surface of the driven shaft is in an elastic deformation state, and it is difficult to generate plastic shakedown;

[0073] (6) When C es_iWhen it is greater than 13.37, large plastic deformation occurs on the contact surface of the driven shaft, and cyclic loading will lead to the accumulation of plastic deformation and cause failure.

[0074] Secondly, regarding the overall structural strength check of the driving shaft and the driven shaft. During the engagement transmission process, the driving shaft and the driven shaft transmit torque and move in the same direction under the contact action of the diagonal support clutch. As mentioned above, the current analysis and check of the driving shaft and the driven shaft based on contact stress and circumferential stress are not comprehensive. In fact, the stresses on the driving shaft and the driven shaft are similar and can both be decomposed into shear stress, compressive stress, and circumferential stress from the diagonal support clutch.

[0075] The main function of the transmission shaft is to transmit torque and it does not bear axial load. Therefore, it can be considered that the load from the axial direction is zero, that is, the driving shaft and the driven shaft are in a two-dimensional stress state. Based on this, the principal stress is derived through the analytical method, and further the comprehensive stress calculation model of the driving shaft and the driven shaft is obtained by using the distortion energy theory (the fourth strength theory).

[0076] Iterative calculations are performed according to the following cycle, and after tending to be stable, the updated W and V are obtained:

[0077]

[0078]

[0079]

[0080] V = W + ψ

[0081]

[0082]

[0083]

[0084]

[0085]

[0086] In the formula, are the inner arc radius of the driving shaft and the outer arc radius of the driven shaft that change dynamically; are respectively the outer arc radius and the inner arc radius of the diagonal support block that change dynamically; Ω is the rotation angle of the diagonal support block that changes dynamically; α is the central angle that changes dynamically; ψ is the included angle of the arc centers of the diagonal support blocks that changes dynamically; The initial values of are respectively R o 、R i 、r o 、r i ; The fixed value Z is the center distance between the inner and outer arcs of the diagonal support block;

[0087] C o 、 C i 、 C s are the influence coefficients of the driving shaft, the driven shaft, and the diagonal support block respectively; b is the width of the diagonal support block;

[0088] C1, C2, and C3 are the Hertz influence coefficient, the Hertz influence coefficient between the diagonal support block and the driving shaft, and the Hertz influence coefficient between the diagonal support block and the driven shaft respectively;

[0089] Δ ce is the radial displacement of the driving shaft caused by centrifugal force,

[0090] ρ o is the material density of the driving shaft, and n o is the rotational speed during the clutch engagement drive;

[0091] The comprehensive stress of the transmission shaft reaches its maximum value at the inner edge. Calculate the maximum comprehensive stress σ of the driving shaft according to the following formula so_max 、 the maximum comprehensive stress σ of the driven shaft si_max :

[0092]

[0093] Specific deformation calculations can be obtained from the reference document "Aeroengine Design Manual Reducer" (pages 318 - 322 of Volume 13).

[0094] Thus, a method for judging the structural strength of the transmission shaft is established:

[0095] (1) When σ so_max ≤σ 0.2(so) and σ si _max ≤ σ 0.2(si) , the driving shaft and the driven shaft are stably engaged in transmission and no structural failure occurs;

[0096] (2) When σ so_max ≥σ 0.2(so) or σ si_max ≥σ 0.2(si) , the driving shaft and the driven shaft will undergo fracture failure during transmission.

[0097] Among them, σ 0.2(so) and σ 0.2(si) are the overall yield stresses of the driving shaft and the transmission shaft respectively.

[0098] B. Shear strength check of the non - engagement section of the driving shaft and the driven shaft

[0099] The driving shaft and the driven shaft at the wedging part of the diagonal brace clutch are subject to complex loads, while the driving shaft and the driven shaft outside the wedging part are only subject to simple torque loads. The following is to establish a checking model for them. Still assume that the inner and outer radii of the driven shaft are R id and R i , and the inner and outer radii of the driving shaft are R o and R od .

[0100] According to the shear Hooke's law and integral transformation, the shear stress calculation models at any point on the driving shaft and the driven shaft from the center of the circle can be obtained respectively. After substituting the calculations, it is obtained that the shear stress at the outer edge of the transmission shaft reaches the maximum value, that is, there are

[0101]

[0102] Therefore, a structural strength discrimination method for the non-wedging section of the inner and outer transmission shafts is established

[0103] (1) When τ o_max ≤[τ0] and τ i_max ≤[τ i , the driving shaft and the driven shaft are stably wedged and transmitted, and no structural damage occurs;

[0104] (2) When τ o_max ≥[τ0] or τ i_max ≥[τ i , the driving shaft and the driven shaft will break during transmission.

[0105] Among them, [τ0] and [τ i are the allowable shear stresses of the driving shaft and the driven shaft respectively.

[0106] Example:

[0107] The working conditions of the diagonal brace clutch in a certain turbine starter are as follows: the steady-state speed is 20,000 r / min; the measured transient starting torque is 315 N·m, and the steady-state transmission torque is 265 N·m. The structural parameters of the transmission shaft and the diagonal brace clutch are as follows: the inner and outer radii, elastic modulus and Poisson's ratio of the driving shaft are 30.5562 mm, 38.7350 mm, 212 GPa and 0.3 respectively; the inner and outer radii, elastic modulus and Poisson's ratio of the driven shaft are 15.8750 mm, 22.225 mm, 212 GPa and 0.3 respectively; the inner and outer arc radii, elastic modulus, Poisson's ratio, length and number of the diagonal brace blocks are 4.4958 mm, 4.5212 mm, 208 GPa, 0.3, 16.8910 mm and 18 respectively; the wedge angles W and V are 2.7865° and 3.8461° respectively; the contact yield stress of the transmission shaft after surface strengthening treatment is uniformly taken as σ c = 1740 MPa, and the overall yield stress is uniformly taken as σ0.2 = 1280 MPa, and the allowable shear stress is uniformly taken as [τ] = 54 Mpa. The strength of the transmission shaft is checked from three aspects as follows.

[0108] 1). Checking the contact surface stability of the wedging section

[0109] Substitute the starting torque into equations (1) and (2), and the contact stability coefficients of the driving shaft and the driven shaft are obtained respectively as

[0110]

[0111] Referring to the checking range (10.30, 13.37], the conclusion 1 can be obtained: only elastic deformation occurs on the contact surface of the driving shaft in the wedging section, and plastic stability occurs on the contact surface of the driven shaft.

[0112] 2). Checking the combined stress of the wedging section

[0113] Substitute into equation (3), and the maximum combined stresses of the wedging sections of the driving shaft and the driven shaft are obtained respectively as

[0114]

[0115] Referring to the overall yield stress σ 0.2 = 1280 MPa, the conclusion 2 can be obtained: the combined stresses of the wedging sections of the driving shaft and the driven shaft are both less than the yield stress, and no plastic yield or failure occurs as a whole.

[0116] 3). Checking the shear stress of the non - wedging section

[0117] Substitute into equation (4), and the maximum shear stresses of the non - wedging sections of the driving shaft and the driven shaft are obtained respectively as

[0118]

[0119] Referring to the allowable shear stress [τ] = 54 Mpa, the conclusion can be obtained: the shear stresses of the non - wedging sections of the driving shaft and the driven shaft are both less than the allowable shear stress, and no shear deformation or failure occurs.

[0120] Those skilled in the art of this technology can understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used here have the same meaning as the general understanding of those of ordinary skill in the art to which this invention belongs. It should also be understood that terms such as those defined in a general dictionary should be understood to have a meaning consistent with the meaning in the context of the prior art, and will not be interpreted with an idealized or overly formal meaning unless defined as here.

[0121] The specific embodiments described above further elaborate on the object, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only the specific embodiments of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for checking the structural strength of a drive shaft in a turbine starter, the drive shaft comprising a driving shaft, a driven shaft and a diagonal brace clutch, and power transmission between the driving shaft and the driven shaft being achieved through the frictional engagement of the diagonal brace clutch, characterized in that, The structural strength checking method includes the following steps: Step 1), obtain the maximum torque T at the start transient t0 of the transmission shaft through actual measurement and output of the load spectrum; let the inner and outer radii of the driving shaft be R o , R od , and the inner and outer radii of the driven shaft be R id , R i ; the distance between the inner and outer raceways is J; the length of the swash block in the swashplate clutch is l, and the radii of the inner and outer profiles are r i , r o ; the wedge angles formed by the swashplate clutch with the driving shaft and the driven shaft are set as W and V respectively; the number of swash blocks in the swashplate clutch is n; Step 2), perform shakedown checking on the contact surfaces of the driving shaft, driven shaft and the swashplate clutch: Step 2.1), as the load T increases, the inclined strut clutch contacts the raceway surfaces of the driving shaft and the driven shaft and gradually flips counterclockwise, and the normal load N of the driving shaft o and the normal load N of the driven shaft i are as follows: Step 2.2), the contact between the arc surface of the swashplate clutch and the raceways of the driving shaft and the driven shaft is line contact. Under frequent contact impacts, plastic deformation will occur on the raceway surfaces of the swashplate clutch, the driving shaft and the driven shaft, the material in the contact area is strengthened, the yield limit increases, and the structure enters the shakedown state; establish the calculation and discrimination formula for the contact shakedown of the swashplate clutch with the driving shaft and the driven shaft: Among them, C es_o and C es_i are the contact stability coefficients of the driving shaft and the driven shaft respectively; E o and E s and E i are the elastic moduli of the driving shaft, the diagonal support block, and the driven shaft respectively; v o and v s and v i are the Poisson's ratios of the driving shaft, the diagonal support block, and the driven shaft respectively; σ so and σ si are the contact yield stresses of the driving shaft and the driven shaft respectively; Step 2.3), according to C es_o and C es_i perform structural stability check and discrimination: Step 2.3.1), when C es_o ∈(10.30, 13.37], plastic deformation occurs on the contact surface between the driving shaft and the diagonal bracing clutch, and the structure tends to be stable after cyclic loading; Step 2.3.2), when C es_o ≤ 10.30, the contact surface of the driving shaft is in an elastic deformation state, and it is difficult to generate plastic shakedown; Step 2.3.3), when C es_o > 13.37, a large plastic deformation occurs on the contact surface of the driving shaft, and cyclic loading will cause the accumulation of plastic deformation and result in failure; Step 2.3.4), when C es_i ∈(10.30, 13.37], plastic deformation occurs on the contact surface between the driven shaft and the diagonal bracing clutch, and the structure tends to be stable after cyclic loading; Step 2.3.5), when C es_i ≤ 10.30, the contact surface of the driven shaft is in an elastic deformation state, and it is difficult to generate plastic shakedown; Step 2.3.6), when C es_i > 13.37, large plastic deformation occurs on the contact surface of the driven shaft, and cyclic loading will cause the accumulation of plastic deformation and surface failure; Step 3), perform overall structural strength checking on the driving shaft and the driven shaft: Step 3.1), perform iterative calculation according to the following cycle, and obtain the updated W and V after reaching stability: V = W + ψ In the formula, are the inner arc radius of the driving shaft and the outer arc radius of the driven shaft that change dynamically; are respectively the outer arc radius and the inner arc radius of the dynamic change of the diagonal brace block; Ω is the rotation angle of the diagonal brace block that changes dynamically; α is the central angle that changes dynamically; ψ is the included angle of the arc center of the diagonal brace block that changes dynamically; The initial values of are R o , R i , r o , r i ; The fixed value Z is the center distance between the inner and outer arcs of the diagonal brace block; C o 、C i 、C s are the influence coefficients of the driving shaft, the driven shaft, and the diagonal support block, respectively; b is the width of the diagonal support block; C1, C2, and C3 are the Hertz influence coefficients between the Hertz influence coefficient, the brace block and the driving shaft, and the Hertz influence coefficient between the brace block and the driven shaft, respectively; Δ ce is the radial displacement of the driving shaft caused by centrifugal force, ρ o is the material density of the driving shaft, n o is the rotational speed during the clutch engagement drive; Step 3.2), calculate the maximum combined stress σ of the driving shaft according to the following formula somax and the maximum combined stress σ of the driven shaft simax as follows: Step 3.3), compare σ so_max with σ 0.2(so) and compare σ si_max with σ 0.2(si) . σ 0.2(so) and σ 0.2(si) are the overall yield stresses of the driving shaft and the transmission shaft respectively; Step 3.3.1), when σ so_max ≤ σ 0.2(so) and σ si_max ≤ σ 0.2(si) , the driving shaft and the driven shaft are stably meshed and transmitted, without structural damage; Step 3.3.2), when σ so_max > σ 0.2(so) or σ si_max > σ 0.2(si) , fracture failure will occur during the transmission of the driving shaft and the driven shaft; Step 4), perform shear strength checking on the non-wedged sections of the driving shaft and the driven shaft: Step 4.1), calculate the maximum shear stress τ of the driving shaft according to the following formula o_max , the maximum shear stress τ of the driven shaft i_max : Step 4.2), compare τ o_max with [τ0], and compare τ i_max with [τ i . [τ0] and [τ i are the allowable shear stresses of the driving shaft and the driven shaft respectively: Step 4.2.1), when τ o_max ≤ [τ0] and τ i_max ≤ [τ i , the driving shaft and the driven shaft are stably engaged in transmission without structural damage; Step 4.2.2), when τ o_max >[τ0] or τ i_max >[τ i , shear fracture failure will occur during the transmission of the driving shaft and the driven shaft.

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