The pace enters electric machinery choose computational method

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The pace enters electric machinery is one kind can change digital input pulse Cheng Xuan to turn or the electromagnetism of linear increment motion carries out component. Every input pace of runner shaft of electric machinery of a pulse to enter increment of horn of a step pitch. Electric machinery answers corner and input pulse number always to become direct proportion, corresponding rotate speed depends on input pulse frequency. The pace enters electric machinery is one of components of the key in Electromechanical unifinication product, be used as to locate normally control and decide fast control. The pace enters electric machinery inertia precision of low, fixed position is tall, without accumulate error, control to wait for a characteristic simply. Apply extensively in Electromechanical unifinication product, be like: Peripheral equipment of numerical control machine tool, package machine, computer, copycat, electrograph. When choice pace enters electric machinery, the output power that should make sure the pace enters electric machinery above all is more than the power that laden place needs. And when choosing diligent rate pace to enter electric machinery, want the laden torsion of computer weapon system above all, the quadrature frequency character of electric machinery can satisfy mechanical load and certain surplus makes sure its move reliable. In real work process, the laden moment of force below all sorts of frequency must be inside the limits of curve of quadrature frequency character. Popularly says the electric machinery with big Mjmax of the largest static moment of force, laden moment of force is large. When choice pace enters electric machinery, should make step pitch horn and mechanical system match, the pulse equivalent that can get machine tool place needs so. There is smaller pulse equivalent to make in mechanical drive process, it is the lead that can change filar lever, 2 it is to be able to pass a pace to be finished into the fractionize drive of electric machinery. But fractionize can change its resolution only, do not change its precision. Precision is by the inherent character of electric machinery place is decided. When choice power pace enters electric machinery, ought to the starting frequency of the laden inertia with estimation laden machinery and machine tool requirement, the made inertial frequency character that takes electric machinery with the pace matchs to still have certain surplus, those who make is highest fast the need that successive job frequency can satisfy a machine tool to move quickly. Choice pace needs to have the following consideration into electric machinery: (1) the decelerate beguine of computational gear occupies a requirement pulse equivalent, gear decelerate is calculated as follows than I: I=(φ .


Δ ) (the φ in 1-1) type---The step pitch part that the pace takes electric machinery (O/ pulse) S---Filar lever pitch (Mm) Δ---(Mm/ pulse) (2) computational workbench, filar lever and gear convert come the inertia Jt on electric machinery axis. Jt=J1+ (1/i2)[(J2+Js) + W/g (S/2 π ) 2] (1-2) the Jt in type---Convert comes the inertia on electric machinery axis (Kg.


S2)J1, J2---Gear inertia (Kg.


S2)Js----Filar lever inertia (Kg.


S2)W---Workbench weight (N) S---Filar lever pitch (Cm) (3) the MM=Ma+Mf+Mt of total moment of force that computational electric machinery outputs (1-3) Ma= (Jm+Jt) .

N/T × 1.

10 ˉ of 02 × 2 (1-4) the Ma in type---Electric machinery is started quicken pitching moment (N.

M)Jm, Jt---Inertia of electric machinery oneself and laden inertia (Kg.


S2)n---The rotate speed that electric machinery place wants to achieve (R/min) T---Electric machinery rises fast time (S) Mf=(u.


10 ˉ of × of I) of S)/(2 π η 2 (1-5) Mf---Slideway attrition convert comes the torsion of electric machinery (N.

M)u---η of coefficient of friction---Deliver efficiency Mt=(Pt.

10 ˉ of × of I) of S)/(2 π η 2 (1-6) Mt---Cutting force convert comes electric machinery moment of force (N.

M)Pt---Force of the biggest cutting (N) (4) estimation of laden starting frequency. Numerical control system controls the starting frequency of electric machinery and laden torsion and inertia to have very big concern, its estimation formula is Fq=fq0[(1-(Mf+Mt))/Ml) ÷ (1+Jt/Jm)]1/2 (1-7) the Fq in type---Belt carry starting frequency (Hz) Fq0---Carry starting frequency Ml for nothing---The electric machinery that decides by quadrature frequency character below starting frequency outputs pitching moment (N.

M) is like laden parameter to cannot decide accurately, can undertake estimation by Fq=1/2fq0.

(5) the highest frequency that move and the computation that rise fast time. Lift and drop as frequency as a result of the output moment of force of electric machinery, because this is when highest frequency, output pitching moment characteristicly by quadrature frequency should drive is laden, stay have enough surplus. (6) laden moment of force and Mmax of the largest static moment of force. Laden moment of force can press type (1-5) with type (1-6) computation, electric machinery is when speed of the biggest feed, the electric machinery that decides by quadrature frequency character outputs pitching moment to want to be more than Mf and Mt the sum, take superabundant amount. Generally speaking, mf and Mt the sum should are less than (0.

2 ~ 0.


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