Vibration generating apparatus

Abstract

A vibration generating apparatus includes a mass body; an, elastic member coupled to the mass body; and a piezoelectric element disposed on one surface of the elastic member facing the mass body, wherein a surface of the mass body facing the piezoelectric element has a shape that prevents contact between the piezoelectric element and the mass body.

What is claimed is: 
     
         1 . A vibration generating apparatus comprising:
 a mass body;   an elastic member coupled to the mass body; and   a piezoelectric element disposed on one surface of the elastic member facing the mass body,   wherein a surface of the mass body facing the piezoelectric element has a shape that prevents contact between the piezoelectric element and the mass body.   
     
     
         2 . The vibration generating apparatus of  claim 1 , wherein the surface of the mass body has one or more stepped parts formed to correspond to the piezoelectric element. 
     
     
         3 . The vibration generating apparatus of  claim 2 , the surface of the mass body comprising an inclined surface from the stepped part toward a distal end of the mass body. 
     
     
         4 . The vibration generating apparatus of  claim 1 ,
 wherein the elastic member comprises:   a bottom plate; and   support plate parts extending vertically from the bottom plate and supporting the mass body, and   wherein the piezoelectric element is installed on a surface of the bottom plate facing the mass body.   
     
     
         5 . The vibration generating apparatus of  claim 1 , further comprising a case transferring vibrations to outside the vibration generating apparatus and coupled with the elastic member.  6 , The vibration generating apparatus of  claim 5 , further comprising one or more damper members attached on an inner surface of the case. 
     
     
         7 . The vibration generating apparatus of  claim 1 , further comprising one or more damage preventing members disposed on a surface of the piezoelectric element facing the mass body. 
     
     
         8 . The vibration generating apparatus of  claim 5 , further comprising one or more buffering members attached on another surface of the elastic member. 
     
     
         9 . The vibration generating apparatus of  claim 8 , wherein the case has at least one opening through which the buffering members are moveable. 
     
     
         10 . The vibration generating apparatus of  claim 5 , wherein an inner surface of the case comprises one or more protrusions supporting end portions of the elastic member. 
     
     
         11 . The vibration generating apparatus of  claim 1 , further comprising a circuit board connected to the piezoelectric element and disposed on the one surface of the elastic member. 
     
     
         12 . The vibration generating apparatus of  claim 11 , wherein:
 the electric member comprises one or more openings exposing an electrode formed on a surface of the piezoelectric element, and   the circuit board comprises an insertion hole, into which the electrode is inserted, and a piezoelectric element connection part inserted into the openings.   
     
     
         13 . The vibration generating apparatus of  claim 11 , wherein the circuit board comprises an external part extended to outside of the case and having a power supply connection terminal. 
     
     
         14 . The vibration generating apparatus of  claim 1 , wherein the elastic member has one or more holes. 
     
     
         15 . The vibration generating apparatus of  claim 2 , wherein the surface of the mass body comprises a curved surface between the stepped part and a distal end of the mass body.