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1、The classic clamping mechanismMachanical Manufacturing technology The clamping mechanism is an important part of the clamping device.No matter what power source device used,you have to use the clamping mechanism to convert the original force into the clamping force.there are many of clamping device
2、using in machine tool,we introduce a few kinds of them,which use mechanical friction to achieve clamping and can self-lock the typical clamping mechanism.Figure 1 is an example of wedge clamping mechanism.Figure a is drilling two holes of 8mm and 5mm perpendicular to each other on the workpiece.Beca
3、use the clamping force is small and laborious when clamping the workpiece with the wedge directly,so the wedge clamping is to use with other mechanisms.Figure b is a combined clamping mechanism composed of the wedge and the pressing plate.Figure c is a manual clamping mechanism composed of the end w
4、edge and the pressing plate.When clamping workpiece manually with wedge,the wedge should have the function of self-locking.Therefore,when designing the wedge clamping mechanism,it is necessary to solve the main problems such as the conversion of the original force and clamping force,the self-locking
5、 condition and the selection of the bevel wedge Angle.u1.wedge clamping mechanismFigure 1 Wedge clamping mechanism Figure 2 Wedge clamping principle and force analysisCharacteristics:Simple structure,small lift,the expansion force multiple is not big,the operation situation is not ideal,but it is wi
6、dely used in combination with the mobile device In addition,increasing the stroke and increasing the clamping force make the wedge self-locking is contradictory,therefore,the selection of the Angle of the wedge must consider these two factors,if both are very strict requirements,the wedge can be mad
7、e into two rising angles,the former section of a large rise angle for increasing the working stroke,the latter section of a small rise angle for the workpiece to tighten and self-locking.Using the screw directly clamping or using the combination of screw and other components to achieve the clamping
8、mechanism,We are called the screw clamping mechanism.Screw clamping mechanism has simple structure,large strength and good self-lock,It is very suitable for manual clamping.It is characterized by slow clamping action,so it is less used in maneuvering clamping.u2.Screw clamping mechanism（1）Simple scr
9、ew clamping mechanism Figure 3 shows the simplest screw clamping mechanism.As shown in figure 3a,the head of the screw is directly in contact with the surface of the workpiece.When the screw rotates,it may damage the surface of the workpiece or drive the workpiece to rotate.The way to overcome this
10、disadvantage is to install the swinging block on the head of the screw shown in figure 3b.Figure 3c is a fast screw clamping mechanism.Figure 3 screw clamping mechanism（2）Screw press mechanism Among the clamping mechanisms,the most variable structure is the screw press mechanism.Four typical mechani
11、sms of screw press mechanism are shown in Figure 4.FIG a and b are moving pressure plates.FIG c and d are rotary pressure plates.Figure 4 screw press mechanism Figure 5 shows the screw hook press mechanism.It is characterized by compact structure and convenience.When the hook plate obstructs the wor
12、kpiece clamping,it can be used by the auto-turn hook plate.Figure.5 screw hook press mechanism the eccentric component directly or indirectly clamping workpiece mechanism.It known as the eccentric clamping mechanism commonly used are the eccentric wheel and eccentric shaft.Figure 6 is an application
13、 example of eccentric mechanism，FIG.a and b use eccentric wheels，FIG.c uses the eccentric shaft,FIG.d uses an eccentric clamping mechanism composed of an eccentric fork u3.eccentric clamping mechanismFigure 6 eccentric clamping mechanismCharacteristics:The clamping force of eccentric clamping mechan
14、ism is small,self-lock is not very good,clamping stroke is small.Mostly used for the area of small cutting force,no vibration,and workpiece size tolerance is not big occasions.The circular eccentric clamping mechanism is a fast clamping mechanism.The linkage clamping mechanism is a kind of efficient
15、 clamping mechanism,Its operation through an handle or a power device,it can clamp a workpiece with multiple clamping point or can be simultaneously clamping multiple workplace.FIG.a is a single contralateral linkage clamping mechanism.FIG.b is a multiple linkage clamping mechanism.u4.linkage clampi
16、ng mechanismFigure 7 Linkage clamping mechanismHow to make the clamping force at the same time uniform pass on each application point is the key.Centering clamping mechanism can not only realize centering function,but also play the role of clamping workpiece.The element in the centering clamping mec
17、hanism that is in contact with the workpiece positioning base is both the positioning element and the clamping element.The working principle is that each centering clamping element moves at the same speed to realize centering.Figure 8 shows the screw centering clamping mechanism.u5.Centering clamping mechanismFigure 8 Screw centering clamping mechanism1、5Slide；2、4V-block jaw；3Adjust lever；6Double screwThank you