Research On Vibratory Compactor Performance And New Working Mechanism

I. Introduction Along with the application of electric-hydraulic control technology on the vibration compactor, the overall performance of the vibration compactor has been greatly improved. Through a lots of test and theoretic studies, especially studies and applications on the theory of vibration compaction, which has pushed the vibration compaction technology to a new level. Basically, vibration compactors adopt hydraulic transmission technology, but on the process of realistic designing and application, there are still some problems with the adaptability of the hydraulic system to the loads, insufficient driving force, low efficiency and damping system. In order to overcome all the above mentioned shortcomings, studies on the overall performance of the vibration compactor and creative designs on a new type working device have been put forward. This essay mainly studies the overall performance of the vibration compactor and the principles and structures of the newly designed working device and performs many related experiments II. Studies on the overall performance of the vibration compactorBy using the basic theoretic technology of the hydrodynamics, this essay educes the flow equation of the hydraulic pump and motor and the balance equation of static moment between the outside loads 式中CCCCt = tp+tm1 +tm2 Total leakage factor Dm1 ——Displacement of front motor(cm3) Dm2 ——Displacement of rear motor(cm3) ωm1 ——Angle speed of front motor(1/s) ωm 2——Angle speed of rear motor(1/s) KP——Pump displacement factor decided by the structure parameter of the pump(cm2) φ——Control input efficiency dimension of the pump (cm) Tm1 ——Output torque of front motor(N﹒cm) TL1 ——Static outside load torque(N﹒cm) Bm1 ——Viscosity friction factor, related to the motor torque efficiency(cm﹒N﹒s) If let TL= constant, then the speed characteristics under the stable status can be obtained. If TL1=0, TL2=0, then the unload speed characteristics can be obtained.If letφ= constant, then the loads characteristics can be obtained. Obviously, due to the effect of leakage of the system, the output speed of the hydraulic motor decrease along with increase of the loads moment. When ωm1 =0, ω2 =0m , the following can be obtained: The speed characteristics and loads characteristics of the dynamic components of the hydraulic system reflect the adaptability of the system to the outside loads. Good or bad matching reflects the reasonability and economy of the designs Vibration compactors have the problem of vibration and isolation of vibration, which means to transfer the vibration effectively while also need to isolate it properly. First, analyze and study the ωφCTDktmppL11 =ωφCTDktmppL12 =TDDTmLmL2211 =material and structure of the damper, put forward that the attenuation characteristics of the damping rubber is caused by the friction between the inside molecules. Simplify the vibration system of the compactor to a second stage system and establish the dynamic equations to educe the transmissibility. The dynamic equations of the second stage system are: Transmissibility is: λFrequency ratio should be 4~10, thenτ≤10%. Therefore, in order to get better effect of isolation of vibration, dampers with small rigid should be adopted; but should not be too small, otherwise the upper part of the machine might have static deformation. In the design of damping system of vibration compactors, within the specified temperature and frequency, the module and loss factor should be kept within the specified range. The module of the rubber material changes along with the change of the frequency of the vibration force. Therefore, this essay puts forward that the vibration compactors should adopt acrylonitrile rubber which has good oil resistivity and loss factor is ????? m( m1 & 2x& ++ mk*3() x&x&12?+x(2k)1*=+0k*2)x2?k1?x1=sinωt222221(1)1λητ= xx=? +η+small under normal temperature, so when the compactors start to vibrating, the upper part of the machine can have a small amplitude This essay puts forward that the driving system adopts series-parallel connection hydraulic system which can be changed between series and parallel connections under different working conditions to solve the problem of skidding and improve the running speed without any effect on the compaction. This essay expatiates the factors that affect the working frequency and reasonable vibration data for matching. III. Creative design of a new working device This essay analyzes the structure of the traditional vibration device and inadaptability to the compaction materials, creatively designs a new one which has dual shafts and stepless adjust of amplitude, expatiates the structure and working principle, makes a stress analysis and studies on the frequency and optimized amplitude of the new device. This new device can realize the stepless adjust of amplitude and even the horizontal vibration to satisfy the needs of different layers and different materials, and can also make compaction in residential areas and some areas which are very sensitive to vertical vibration. With the aid of the closed circuit formed by the control system, intellectualized compaction can be realized. IV. Tests and studies of the performance This essay makes tests on the traction performance, compaction performance and damping performance of YZ26 Vibration Compactor under the real soil condition, the conclusion isreached as following: 1) The damper can meet the demands of the machine and obtain perfect damping effects under the situation of large amplitude. 2) The vibration compactor can reach satisfied deep compacting effects after several times of compaction, and the compaction speed is around 2-4km/h. 3)The traction characteristics of the hydraulic system can meet the demands of the machine, series and parallel system has the function of the anti-skidding.