Unidirectional-driven drug infusion device

Abstract

A unidirectional-driven drug infusion device, includes: a reservoir, a piston and a screw, the piston is arranged in the reservoir; a driving module which includes at least one driving wheel and at least one driving arm that cooperate with each other, the circumferential surface of the driving wheel is provided with wheel teeth; a power module coupled to the driving arm; a control module, connected to the power module, controls the power module to apply different driving powers to the driving arm, making the driving arm perform linear reciprocating motion; and a friction member which is in contact with the surface of the driving wheel. This device can fully utilize the internal space of the infusion device, and its weight and volume is reduced.

1 . A unidirectional-driven drug infusion device, includes:
 a reservoir, a piston and a screw, wherein the piston, connected with the screw, is arranged in the reservoir;   a driving module which includes at least one driving wheel and at least one driving arm that cooperate with each other, a circumferential surface of the driving wheel is provided with wheel teeth which can be pushed to rotate the driving wheel, driving the screw forward;   a power module coupled to the at least one driving arm;   a control module, connected to the power module, controls the power module to apply different driving powers to the driving arm, making the driving arm perform linear reciprocating motion, thus, driving the driving wheel to rotate; and   a friction member which is in contact with the surface of the driving wheel and increases the maximum static friction force received by the driving wheel.   
     
     
         2 . The unidirectional-driven drug infusion device of  claim 1 , wherein
 the different driving powers applied by the power module to the driving arm includes different linear directions or different magnitudes.   
     
     
         3 . The unidirectional-driven drug infusion device of  claim 2 , wherein
 the driving arm includes a variety of different motion amplitudes or a variety of different motion rates.   
     
     
         4 . The unidirectional-driven drug infusion device of  claim 3 , wherein
 the power module includes a first power unit and a second power unit respectively connected to the driving arm, and by the action of the power module, the driving arm is controlled to push the wheel teeth in its only one motion direction.   
     
     
         5 . The unidirectional-driven drug infusion device of  claim 4 , wherein
 the first power unit includes an electrically driven linear actuator or an electrically heated linear actuator while the second power unit includes an electrically driven linear actuator, an electrically heated linear actuator or an elastic member, and the control module controls the frequency or the magnitude of the power exerted by the first power unit and the second power unit, in order to control the motion amplitude or motion rate of the driving arm.   
     
     
         6 . The unidirectional-driven drug infusion device of  claim 5 , wherein
 the first power unit is an advancing member while the second power unit is a reset member, during the operation, the advancing member applies power to the driving arm to push the wheel teeth forward, while the reset member applies power to the driving arm to make the driving arm reset.   
     
     
         7 . The unidirectional-driven drug infusion device of  claim 1 , wherein
 the driving wheel is a ratchet wheel, the wheel teeth are ratchet teeth, the driving arm is a pawl which pushes the ratchet teeth to make the ratchet wheel rotate intermittently.   
     
     
         8 . The unidirectional-driven drug infusion device of  claim 1 , wherein
 the driving arm includes two driving ends, arranged up and down, whose front ends are not flush, and the two driving ends can alternately push the wheel teeth.   
     
     
         9 . The unidirectional-driven drug infusion device of  claim 1 , wherein
 the friction member has elasticity, and the contact position of the friction member with the surface of the driving wheel includes the tooth surface or the non-tooth surface of the driving wheel.   
     
     
         10 . The unidirectional-driven drug infusion device of  claim 9 , wherein
 the unidirectional-driven drug infusion device further includes a base which includes the friction member, and the driving wheel is movably assembled on the base where the friction member is located and frictionally fits with the friction member.   
     
     
         11 . The unidirectional-driven drug infusion device of  claim 10 , wherein
 the friction member is arranged on the base, and the friction member is frictionally fitted with the side surface of the driving wheel.