How to calculate the clamping force of coupling
the standard diameter should be used as far as possible for the shaft section with matching requirements. The shaft diameter of the installation standard parts (such as rolling bearing, coupling, sealing ring, etc.) shall be taken as the corresponding standard value and the tolerance of the selected fit
in order to facilitate the assembly and disassembly of gear, bearing and other parts with matching requirements, and rece the scratch on the matching surface, a smaller diameter should be used before matching the shaft section. In order to make it easy to assemble the parts with interference fit with the shaft, the pressing end of the matching shaft section should be tapered; Or adopt different dimensional tolerance on two parts of the same shaft section
when determining the length of each shaft segment, the structure should be as compact as possible, and the assembly or adjustment space required by the parts should also be ensured. The length of each section of the shaft is mainly determined according to the axial size of the parts and the shaft fitting part and the necessary gap between adjacent parts. In order to ensure the reliable axial positioning, the length of the shaft section matched with the gear, coupling and other parts should generally be 2 ~ 3mm shorter than the hub length
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(A1-A3) / 2 -------- (1-9)
h2 = (L1 + L2) * (
S1-S3) / d
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(A1-A3) / 2 -------- (1-10) where H1
, H2 -------- the adjustment amount of fulcrum 1 and fulcrum 2, (positive value is cushion, negative value is cushion), mm
S1, S3 and A1, A3 --- respectively 0 ° And 180 ° The readings of axial and radial dial indicator measured by azimuth, mm
d -------- calculated diameter of coupling (dial indicator contact, i.e. distance from measuring point to coupling center point), mm
L1 -------- distance between fulcrum 1 and measuring plane of coupling, mm
L2 -------- distance between fulcrum 1 and fulcrum 2, mm; When using the above formula to calculate the adjustment amount, some notes are as follows: 1) S1, S3, A1, A3 are the readings measured by the dial indicator, which should be substituted into the calculation formula together with the positive and negative signs.
2) the calculated value of H is composed of two terms. In the preceding term L (S1-S3) / D, l and D cannot have negative values, so the positive and negative values of this term are determined by (S1-S3). When S1-S3 > 0, the preceding term is positive, and the axial clearance of the coupling is in shape, It is called "upper mouth opening"; When S1-S3 ＜ 0, the former is negative, and the gap of the coupling is shaped, which is called "lower opening". When A1-A3 ＞ 0, the latter is positive, and the center of the measured half coupling (driving shaft center) is lower than that of the reference half coupling (driven shaft center). When A1-A3 ＜ 0, the center of the measured half coupling is higher,
③ when the machine is installed, the rotating shaft (driven shaft) of the main engine is usually used as the reference, Adjust the motor rotating shaft (driving shaft). The four fulcrums of the motor low seat are symmetrically arranged on both sides. During adjustment, the thickness of the gasket added (or subtracted) by the two symmetrical fulcrums should be equal.
④ if the structure of the fixture (wheel clamp) for installing the dial indicator is different, and the contact point of the dial indicator for measuring the axial clearance points to the prime mover (the contact point contacts with the end face of the tested half coupling close to the joint surface), The reading value of the dial indicator is just opposite to the direction of the actual axial clearance between the couplings, so the preceding item S1-S3 of the H value formula should be changed to s3-s1, that is, when s3-s1 > 0, it is "upper opening", and when s3-s1 < 0, it is "lower opening"
(1) Membrane stress caused by torque of diaphragm coupling. Let the torque transmitted be t (N.m) and the total number of bolts be m. for 8-hole bolts, the simplified condition shows that the torque of single diaphragm T1 = t / M and the force on each main bolt f = t / 4mr
(2) centrifugal stress e to inertia ring high speed rotation. Assuming that the material of bolt and coupling diaphragm is the same, their respective mass can be calculated. According to their position and helix angle, the centrifugal force can be calculated and acted on the total mass center. The centrifugal inertia force of high-speed machinery is very important in the structural stress calculation. The centrifugal inertia force can be loaded according to the radial force F = (2 Π n / 60) 2rp, and the direction is radial outward. The radial displacement, circumferential displacement and axial displacement of the middle bolt hole are fixed, and there is no other load around
(3) e to the axial installation error, the diaphragm is bent along the axial direction. The displacement is loaded in the axial direction of the middle bolt hole, and the radial displacement and axial displacement are fixed. Two middle spaces at both ends are used to impose constraints, and the middle hole is used to bear the load. In this way, it is treated as a statically determinate simply supported mechanism< (4) bending stress caused by angular installation error. It can be solved according to the simplification in the figure below. Because of the actual installation error in the axis angle direction, the diaphragm will be periodically bent along the axis direction, and it is the main reason to determine the fatigue life of the coupling diaphragm. According to the calculation of angular deviation, the axial displacement, radial displacement and axial displacement of the middle bolt hole are fixed. Generally, the angular displacement of the coupling diaphragm is very small, so the deformation of the diaphragm belongs to small deformation, which can be analyzed by the small deflection bending theory of thin plate
when the chuck is released, the spindle rotates, and the soft claw is turned with the inner diameter turning tool, and the inner diameter is turned to the outer diameter of the workpiece
tighten the chuck with bushing (outer diameter dimension of workpiece), and continue turning the soft claw with inner diameter cutter until the outer diameter dimension of workpiece;
is balanced by the copoint force condition 2F = g
by F= μ N
N=G/2 μ μ Friction coefficient between object and gripper
gripping force n ≥ g / 2 μ There must be no problem
F: angle cylinder clamping force (kg)
P: service pressure (kgf / cm2)
A1: piston acceptance area (cm2)
A: piston rod diameter area (cm2)
A2: piston pulling in area