Effects of Structural Characteristics of a Wet Multi-Disk Clutch on Contact Pressure

doi:10.12382/bgxb.2021.0618

Abstract

Abstract:

Based on the structural characteristics of a wet multi-disk clutch, a finite element model and a thermodynamic model of a multi friction-pair system are developed. The influence of structural parameters on the contact pressure between friction pairs are studied, including backplate thickness, circlip width, and number of friction pairs. Moreover, the correctness of the numerical model is verified by clutch static pressure experiments. An index is employed to evaluate the pressure differences between friction pairs, and the optimal structural parameters of the clutch are proposed. The results show that the backplate thickness and circlip width have strong effects on the pressure difference, while the number of friction pairs only has a slight influence. The differences between the contact pressure and radial temperature of friction pairs can be significantly smoothed out by increasing the plate thickness and circlip width. As compared with the initial structural conditions, the maximum differences of the control pressure and radial temperature at the optimum condition are reduced by 82% and 61%, respectively.

Key words: wet multi-disk clutch, structural characteristics, contact pressure, temperature field

CLC Number:

U463.2

CHEN Man, LIU Yujian, YU Liang, WANG Xu, ZHANG Cunzhen, HU Lin. Effects of Structural Characteristics of a Wet Multi-Disk Clutch on Contact Pressure[J]. Acta Armamentarii, 2023, 44(2): 406-416.

Figures/Tables 29

Fig.1 3D schematic diagram of a wet multi-disk wet clutch

Fig.2 Pressure transmission model on the semi-infinite plate

Fig.3 Finite element model of the clutch

Table 1 Material and structural parameters of friction pairs

摩擦元件	r_i/mm	r_o/mm	厚度 H/mm	ν	弹性模量 E/GPa
活塞	85	125	6	0.29	210
钢片	85	125	3	0.29	210
摩擦衬片	85	125	0.6	0.27	2.2
摩擦基片	85	125	2	0.29	210
压板	85	125	6	0.29	210
卡簧	122	125	3	0.29	210

Fig.4 Pressure clouds of a 6-friction-pairs system

Fig.5 Radial pressure in the initial working conditions

Fig.6 Changes of pressure under different backplate thicknesses

Fig.7 Radial pressure of S6 under different backplate thicknesses

Fig.8 Diagram of pressure transfer

Fig.9 Changes of pressure under different circlip widths

Fig.10 Radial pressure distribution of S6 under different circlip widths

Fig.11 Radial pressure of different friction pairs

Fig.12 Radial pressure of friction pairs near the circlip side

Table 2 Influencing factors

结构参数		k₁/ (kPa·mm^-1)	k₂/ (kPa·mm^-1)	k₃(k₁+k₂)/ (kPa·mm^-1)
压板厚度	8mm	0.69	8.36	9.05
	10mm	0.53	4.94	5.47
卡簧宽度	6mm	1.48	8.26	9.74
	9mm	2.06	3.38	5.44
摩擦副数	12副	1.2	16.28	17.48
	18副	1.6	17.18	18.78

Fig.13 Pressure before and after optimization

Fig.14 S6 radial pressure before and after optimization

Fig.15 Test systems and samples

Fig.16 Pressure in LLW test paper under initial working conditions

Fig.17 Experimental pressure under initial working conditions

Fig.18 Pressure in LLW test paper with different backplate thicknesses

Fig.19 Experimental pressure for different backplate thicknesses

Fig.20 Pressure in LLW test paper with different circlip widths

Fig.21 Experimental pressure data for different circlip widths

Fig.22 Pressure in LW test paper with different friction pairs

Fig.23 Experimental pressure data for different friction pairs

Fig.24 Pressure in LLW test paper before and after optimization

Fig.25 Experimental pressure data before and after optimization

Fig.26 Temperature field of initial working conditions

Fig.27 Temperature field of optimized working conditions

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