Pump

Abstract

In a cylinder, a plunger is reciprocated in a plunger receiving hole to pressurize fluid in a pump chamber. A delivery passage hole extends in a direction generally perpendicular to an axis of the plunger receiving hole from the pump chamber to a radial intermediate location of the cylinder, which is located between the pump chamber and an outer peripheral surface of the cylinder in a radial direction of the cylinder. A tilted delivery passage hole is tilted relative to the axis of the plunger receiving hole and extends from a portion of the delivery passage hole, which is radially spaced from the pump chamber, toward the outside of the cylinder.

1 . A pump comprising:
 a cylinder that defines:
 a pump chamber; 
 a plunger receiving hole that is continuous from the pump chamber and is coaxial with the pump chamber; 
 an intake passage that is communicated with the pump chamber to supply fluid from an external fluid supply source to the pump chamber; and 
 a delivery passage that is communicated with the pump chamber to output the fluid from the pump chamber to an outside of the cylinder; and 
   a plunger that is received in the plunger receiving hole in a reciprocable manner to pressurize the fluid in the pump chamber and to deliver the pressurized fluid out of the pump chamber through the delivery passage, wherein the delivery passage includes:
 a lateral delivery passage hole that extends through the pump chamber in a direction generally perpendicular to an axis of the plunger receiving hole and includes:
 a first hole section that extends from the pump chamber to an outer peripheral surface of the cylinder and is closed with a closing member; and 
 a second hole section that extends from the pump chamber to a radial intermediate location of the cylinder, which is located between the pump chamber and the outer peripheral surface of the cylinder in a radial direction of the cylinder; and 
 
 a tilted delivery passage hole that is tilted relative to the axis of the plunger receiving hole and extends from a portion of the second hole section, which is radially spaced from the pump chamber, toward the outside of the cylinder. 
   
   
   
       2 . The pump according to  claim 1 , wherein:
 the first hole section includes:
 a large diameter hole portion that opens to the pump chamber; 
 a small diameter hole portion that has an inner diameter smaller than that of the large diameter hole portion and opens to the outer peripheral surface of the cylinder; and 
 a step portion that is located between the large diameter hole portion and the small diameter hole portion; and 
   the closing member is urged against the step portion to close the first hole section though engagement between the closing member and the step portion.   
   
   
       3 . The pump according to  claim 2 , wherein the step portion is tapered. 
   
   
       4 . The pump according to  claim 2 , wherein the closing member is generally spherical. 
   
   
       5 . The pump according to  claim 1 , wherein the closing member is threadably fixed to the first hole section from the outer peripheral surface side of the cylinder. 
   
   
       6 . The pump according to  claim 1 , wherein the closing member is press fitted into the first hole section. 
   
   
       7 . The pump according to  claim 1 , wherein the closing member is securely welded to the cylinder. 
   
   
       8 . A pump comprising:
 a cylinder that defines:
 a pump chamber; 
 a plunger receiving hole that is continuous from the pump chamber and is coaxial with the pump chamber; 
 an intake passage that is communicated with the pump chamber to supply fluid from an external fluid supply source to the pump chamber; and 
 a delivery passage that is communicated with the pump chamber to output the fluid from the pump chamber to an outside of the cylinder; and 
   a plunger that is received in the plunger receiving hole in a reciprocable manner to pressurize the fluid in the pump chamber and to deliver the pressurized fluid out of the pump chamber through the delivery passage, wherein the delivery passage includes:
 a delivery passage hole that extends in a direction generally perpendicular to an axis of the plunger receiving hole from the pump chamber to a radial intermediate location of the cylinder, which is located between the pump chamber and an outer peripheral surface of the cylinder in a radial direction of the cylinder; and 
 a tilted delivery passage hole that is tilted relative to the axis of the plunger receiving hole and extends from a portion of the delivery passage hole, which is radially spaced from the pump chamber, toward the outside of the cylinder.