Chambers* Micromanipulator* Construction and Working Principle. 



This is a mechanical device whereby very fine movement of microneedles, micro- 

 pipettes, etc., suitable for manipulating microscopic objects under high magni- 

 fication may be effected. The apparatus consists of two instruments, right and 

 left, which are mirror images of each other. The right hand instrument is the 

 one which, If held in such a position that the free end of the heavy cylindrical 

 pillar points downard, the three large screws will be in a horizontal position 

 to the right. Each instrument is mounted by inserting the pillar into a pillar 

 socket attached to the heavy supporting base plate. The parts of which an instru- 

 ment is composed and the principle on which it operates are as shown in figure 1. 



Three bars of rigid metal are connected at their ends to form a "z-like" figure 

 by resilient metal acting as a spring-hinge. By the action of the micrometer 

 screws, the bars can be forced apart; on reversing the screws, the bars return 

 to their original position owing to the spring action at the end of the bars. 

 By this means, arc movements may be imparted to the tip of a needle when mounted 

 in its holder on the free end of the third bar. 



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 The needle, or any other suitable device, the tip of which is to be manipulated, 

 is held in a carrier called the adapter fastened to the free end of a bar "A" at 

 "X M . The needle is made to extend so that its tip is at the apex of an imaginary 

 triangle at "D M . In order to obtain two movements at right angles to one another 

 and in the horizontal plane, the tip of the needle must be at the apex "D" of a 

 right-angled triangle the base of which is a straight line joining the centers "E" 

 and "P" of the two springs holding the three bars, "A", "B" and "0" together. The 

 shank of screw M G" passes through a large hole in bar "C" and is screw-threaded 

 in bar n B". Turning it spreads apart bars "A" and "B" and imparts an arc movement 

 to the needle-tip at "D" at right angles to that procured by turning screw "H". 



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