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National transportation infrastructure, city construction scale is more and more big, the scale, the power in construction is more and more big, traction speed more and more quickly, the key transmission accordingly hoist a drum open gear pair structure size bigger, noise hoist in operation, high speed and high power increasingly, however, this is not allowed by the national standard. Building hoist the national standard GB1955 - 2002 provisions hoist noise qualified limits for machine shall not be greater than 85dB (A), the operator shall not be greater than 88dB (A) ears. When the traction force is small, low speed when the noise is far less than the standard limit, easy control; but when the traction speed is higher, traction force to ensure that the noise does not exceed the standard, effective measures should be taken from the aspects of design, technology, materials, quality inspection etc..

1 存在問題：卷揚機噪聲來源有多種途徑，但本質(zhì)上是撞擊和振動的結(jié)果，一般是由于齒輪嚙合質(zhì)量差、運動不平穩(wěn)在運動中產(chǎn)生了瞬時加速度而造成的。 我公司生產(chǎn)的卷揚機噪聲一般在標(biāo)準(zhǔn)范圍以內(nèi)，但出現(xiàn)偶爾噪聲超標(biāo)現(xiàn)象。在排除噪聲時感到無從下手，因機器制造所依據(jù)的圖樣、工藝流程相同，既然絕大多數(shù)產(chǎn)品合格，就應(yīng)排除設(shè)計和工藝不合理因素。

1 problems: the noise sources in various ways, but the essence is the impact and vibration results, is generally caused by gear meshing quality is poor, the unstable movement in motion produced transient acceleration. The noise produced by our company is generally in the standard range, but occasionally noise exceed the standard phenomenon. Unable to gain the upper hand in eliminating noise, drawings, process flow on the basis for machine manufacturing the same, since the vast majority of products qualified, it should eliminate the unreasonable factors in design and technology.

噪聲來源分析及控制

Noise analysis and control of the source

1、底盤 我們認為底盤的設(shè)計制造存在造成噪聲的可能：①底盤采用箱形結(jié)構(gòu)，不是所有焊縫都進行連續(xù)焊接，各個底盤焊縫的長短、高低位置不同，底盤剛性存在較大個體差異，有的則產(chǎn)生共鳴效應(yīng)，機器如有一點震動噪聲就被放大；②底盤由鋼板焊成，不具備吸震消聲功能，如果其固有頻率與齒輪嚙合頻率接近就可能造成個別機器因齒輪弱小震動引發(fā)較大共震，引起噪聲值上升。 我們針對上述可能性分別進行試驗，但通過三次實驗發(fā)現(xiàn)噪聲高低與底盤結(jié)構(gòu)、剛度、頻率等因素呈弱相關(guān)，噪聲大小與運動件強相關(guān)，因此底盤設(shè)計構(gòu)造、制造質(zhì)量并不是噪聲超標(biāo)的原因。

1, we consider the design and manufacture of chassis chassis cause noise may be: ① chassis adopts box type structure, not all welds are continuous welding, various chassis weld length, height, there are great individual differences in the chassis rigidity, others produce resonance effect, the machine such as a little vibration noise is magnified; the chassis is composed of steel plate welded, does not have the shock-absorbing silencing function, if is close to the natural frequency and the gear mesh frequency may cause individual machines for gear weak vibration lead to greater resonance, noise caused by increased. The possibilities are tested, but by three experiments showed a weak correlation factors of noise level and the chassis structure, stiffness, frequency, noise and the size of the moving parts strongly correlated, so the chassis structural design, manufacturing quality and not exceed the standard of noise.

2、軸承間隙 有人認為，既然噪聲是伴隨卷筒總成和傳動件，那么就可能由于卷筒滑動軸承間隙大而引起。我們對卷筒零件配合間隙進行選擇，保證軸承孔與主軸間隙符合圖紙要求，裝配后進行試驗。試驗時采用變頻電機調(diào)速，觀察速度對噪聲的影響。大量試驗結(jié)果表明，速度對噪聲影響是第一位的，卷筒轉(zhuǎn)速越高則噪聲值越大、機器震動越激烈；間隙在其次，主軸與軸套間隙越大則噪聲也越大；而底盤對噪聲影響最小。如果機器本來噪聲就很低，則速度高低、主軸間隙大小的變化都不會產(chǎn)生過大噪聲，由此表明噪聲超標(biāo)也不是由軸承間隙大而引起的。

2, the bearing clearance is considered, since noise is accompanied by a drum assembly and transmission parts, then most likely caused by the roll bearing clearance. We on the drum parts with the gap of selection, ensure the bearing hole and shaft gap with the requirements of the drawings, assembly test. Test by frequency conversion motor, observed the influence of velocity on noise. The experimental results show that the effect of noise, speed is the first drum speed, higher noise value is greater, the machine vibration is more intense; the gap in the second, main shaft and the shaft sleeve gap the greater the noise is larger; while the chassis of the lowest noise. If the machine was very low noise, changes in speed, spindle gap size is not too large noise, the noise exceed the standard is not caused by a large bearing clearance.