Combination of a chamber and a piston, a pump, a motor, a shock absorber and a transducer incorporating the combination

Abstract

A combination of a piston and a chamber, wherein the chamber defines an elongate chamber having a longitudinal axis, the chamber having, at a first longitudinal position thereof, a first cross-sectional area thereof and, at a second longitudinal position thereof, a second cross-sectional area, the second cross-sectional area being 95% or less of the first cross-sectional area, the change in cross-section of the chamber being at least substantially continuous between the first and second longitudinal positions, the piston being adapted to adapt itself to the cross-section of the chamber when moving from the first to the second longitudinal position of the chamber. The piston may comprise an umbrella-like support structure or a fibre enforced deformable container comprising a foam or a fluid. The combination may be used in a pump, a linear actuator, a motor, or a shock absorber.

1 . A piston-chamber combination device comprising an elongate chamber which is bounded by an inner chamber which is bounded by an inner chamber wall and comprising a piston in said chamber to be sealingly movable relative to said chamber to at least between first and second longitudinal positions of said chamber, 
 said chamber having cross-sections of different cross-sectional areas at the first and second longitudinal positions of said chamber and at least substantially continuously different cross-sectional areas at intermediate longitudinal positions between the first and second longitudinal positions thereof, the cross-sectional area at the first longitudinal position being larger than the cross-sectional area at the second longitudinal position,    said piston including a piston body and sealing means supported by the piston body for sealing on said inner chamber wall, the piston body being designed to adapt itself and said sealing means to said difference cross-sectional areas of said chamber during the relative movements of said piston from the first longitudinal position through said intermediate longitudinal positions to the second longitudinal position of said chamber.    
   
   
       2 . The device according to  claim 1 , wherein the cross-sectional area of said chamber at the second longitudinal position thereof is between 95% and 15% of the cross-sectional area of said chamber at the first longitudinal position thereof.  
   
   
       3 . The device according to  claim 1 , wherein the cross-sectional area of said chamber at the second longitudinal position thereof is 95-70% of the cross-sectional area of said chamber at the first longitudinal thereof.  
   
   
       4 . The device according to  claim 1 , wherein the cross-sectional area of said chamber at the second longitudinal position thereof is approximately 50% of the cross-sectional area of said chamber at the first longitudinal thereof.  
   
   
       5 . The device as in  claim 1  adapted to operate as a pump for pumping fluid, further including: 
 means for engaging the piston from a position outside the chamber;    a fluid entrance connected to the chamber and comprising a valve means; and    a fluid exit connected to the chamber.    
   
   
       6 . The device according to  claim 5 , where the engaging means have an outer position when the piston is at the first longitudinal position of the chamber, and an inner position where the piston is at the second longitudinal position of the chamber.  
   
   
       7 . The device according to  claim 5 , wherein the engaging means have an outer position wherein the piston is at the second longitudinal position of the chamber, and an inner position where the piston is that the first longitudinal position of the chamber.  
   
   
       8 . The device as in  claim 1  adapted to operate as a shock absorber further comprising: 
 means for engaging the piston from a position outside the chamber,    wherein the engaging means have an outer position where the piston is at the first longitudinal position of the chamber, and an inner position where the piston is at the second longitudinal position.    
   
   
       9 . The device according to  claim 8 , further comprising a fluid entrance connected to the chamber and comprising a valve means.  
   
   
       10 . The device according to  claim 8 , further comprising a fluid exit connected to the chamber and comprising a valve means.  
   
   
       11 . The device according to  claim 8 , wherein the chamber and the piston form an at least substantially sealed cavity comprising a fluid, the fluid being compressed when the piston moves from the first to the second longitudinal positions of the chamber.  
   
   
       12 . The device according to  claim 8 , further comprising means for biasing the piston toward the first longitudinal position of the chamber.  
   
   
       13 . The device as in  claim 1  adapted to operate as an actuator further comprising: 
 means for engaging the piston from a position outside the chamber,    means for introducing fluid into the chamber in order to displace the piston between the first and the second longitudinal positions of the chamber.    
   
   
       14 . The device according to  claim 13 , wherein the means for introducing fluid into the chamber further comprise a fluid entrance connected to the chamber and comprising a valve means.  
   
   
       15 . The device according to  claim 13 , further comprising a fluid exit connected to the chamber and comprising a valve means.  
   
   
       16 . The device according to  claim 13 , further comprising means for biasing the piston toward the first or second longitudinal position of the chamber.  
   
   
       17 . The device according to  claim 13 , wherein the introducing means comprise means for introducing pressurized fluid into the chamber.  
   
   
       18 . The device according to  claim 13 , wherein the introducing means are adapted to introduce a combustible fluid, such as gasoline or diesel, into the chamber, and wherein the actuator further comprises means for combusting the combustible fluid.  
   
   
       19 . The device according to  claim 13 , further comprising a crank adapted to translate the translation of the piston into a rotation of the crank.  
   
   
       20 . A piston-chamber combination device comprising an elongate chamber and a piston in the chamber adapted to be sealingly movable relative to the chamber at least between first and second longitudinal positions of said chamber, wherein 
 the chamber includes a first cross-sectional area at the first longitudinal position which is greater than a second cross-sectional area at a second longitudinal position and at least substantially continuously differing cross-sectional areas at intermediate longitudinal positions between the first and second longitudinal positions,    the piston including an elastically deformable material for sealing on an inner chamber wall of the chamber and adapted to adapt itself to the different cross-sectional areas of said chamber during the relative movements of the piston between the first longitudinal position and the second longitudinal position of the chamber.