Cam ring of vane pump and method of manufacturing cam ring

Abstract

A cam ring of a vane pump and a method of manufacturing a cam ring are provided. The cam ring may be formed of a material including approximately 3.0% to 3.5% of carbon (C), approximately 2.0% to 2.5% of silicon (Si), approximately 0.5% to 1.0% of manganese (Mn), approximately 0.5% to 1.0% of chromium (Cr), approximately 0.2% to 0.5% of copper (Cu), approximately 0.1% to 0.3% of phosphor (P), approximately 0.02% to 0.06% of boron (B), approximately 0.06% to 0.1% of sulfur (S), and approximately 0.043% or more of titanium (Ti) by weight ratio, and iron (Fe) and any inevitable impurity for the remainder, and may have a tempered martensite matrix including a carbide.

What is claimed is: 
     
         1 . A cam ring of a vane pump formed of a material including approximately 3.0% to 3.5% of carbon (C), approximately 2.0% to 2.5% of silicon (Si), approximately 0.5% to 1.0% of manganese (Mn), approximately 0.5% to 1.0% of chromium (Cr), approximately 0.2% to 0.5% of copper (Cu), approximately 0.1% to 0.3% of phosphor (P), approximately 0.02% to 0.06% of boron (B), approximately 0.06% to 0.1% of sulfur (S), and approximately 0.043% or more of titanium (Ti) by weight ratio, and iron (Fe) and any inevitable impurity comprising the remainder, and having a tempered martensite matrix structure including a carbide. 
     
     
         2 . The cam ring of  claim 1 , wherein the cam ring includes approximately 3% to 10% of carbide by volume ratio. 
     
     
         3 . The cam ring of  claim 2 , wherein the tempered martensite matrix structure of the cam ring is a structure in which a carbide and A-type flake graphite are precipitated. 
     
     
         4 . The cam ring of  claim 1 , wherein the material includes approximately 3.2% to 3.5% of carbon (C), approximately 2.11% to 2.5% of silicon (Si), approximately 0.62% to 1.0% of manganese (Mn), approximately 0.77% to 1.0% of chromium (Cr), approximately 0.2% to 0.45% of copper (Cu), approximately 0.15% to 0.3% of phosphor (P), approximately 0.035% to 0.06% of boron (B), approximately 0.07% to 0.096% of sulfur (S), and approximately 0.038% or more of titanium (Ti) by weight ratio, and iron (Fe) and any inevitable impurity comprising the remainder. 
     
     
         5 . The cam ring of  claim 1 , wherein the material includes approximately 3.2% to 3.38% of carbon (C), approximately 2.2% to 2.34% of silicon (Si), approximately 0.66% to 1.0% of manganese (Mn), approximately 0.77% to 0.842% of chromium (Cr), approximately 0.35% to 0.45% of copper (Cu), approximately 0.069% to 0.3% of phosphor (P), approximately 0.035% to 0.043% of boron (B), approximately 0.083% to 0.096% of sulfur (S), and approximately 0.035% or more of titanium (Ti) by weight ratio, and iron (Fe) and any inevitable impurity comprising the remainder. 
     
     
         6 . A method for manufacturing a cam ring of a vane pump, the method comprising:
 mixing raw materials including approximately 3.0% to 3.5% of carbon (C), approximately 2.0% to 2.5% of silicon (Si), approximately 0.5% to 1.0% of manganese (Mn), approximately 0.5% to 1.0% of chromium (Cr), approximately 0.2% to 0.5% of copper (Cu), approximately 0.1% to 0.3% of phosphor (P), approximately 0.02% to 0.06% of boron (B), approximately 0.06% to 0.1% of sulfur (S), and approximately 0.043% or more of titanium (Ti) by weight ratio, and iron (Fe) comprising the remainder and melting the mixture to obtain a crude liquid molten metal;   injecting the crude liquid molten metal into a mold so as to be cast to obtain a semi-product;   machining the casted semi-product to form a cam ring; and   heat-treating the machined cam ring   
     
     
         7 . The method of  claim 6 , wherein, in the mixing, the crude liquid molten metal is taken out at a temperature ranging from approximately 1500° C. to 1550° C. 
     
     
         8 . The method of  claim 6 , further comprising injecting an inoculant into the crude liquid molten metal. 
     
     
         9 . The method of  claim 8 , wherein the inoculant is a barium silicon iron alloy (FeSi72Ba2) and inoculates approximately 0.3% to 0.5% of a mass of the crude liquid molten metal. 
     
     
         10 . The method of  claim 6 , wherein during the heat-treating, after quenching, tempering is performed. 
     
     
         11 . The method of  claim 10 , wherein the quenching comprises:
 heating the cam ring semi-product at a temperature ranging from approximately 890° C. to 930° C. and maintaining the heated cam ring semi-product for approximately 1.5 to 2.5 hours;   cooling the cam ring semi-product with a quenching oil having a temperature ranging from approximately 50° C. to 90° C.; and   cooling the cam ring semi-product to reach approximately room temperature in the atmosphere.   
     
     
         12 . The method of  claim 10 , wherein the tempering comprises:
 heating the quenched cam ring semi-product at a temperature ranging from approximately 220° C. to 250° C. and maintaining the heated cam ring semi-product for approximately 1.5 to 2.5 hours; and   cooling the cam ring semi-product to reach approximately room temperature in the atmosphere.   
     
     
         13 . The method of  claim 6 , wherein, during the injecting, stream inoculation is performed with a sulfur oxygen injection. 
     
     
         14 . The method of  claim 13 , wherein a content of the sulfur oxygen injection is approximately 0.05˜0.15% of a mass of the crude liquid molten metal. 
     
     
         15 . The method of  claim 6 , further comprising:
 grinding the heat-treated cam ring to have final dimensions and shape.   
     
     
         16 . The method of  claim 6 , wherein the raw materials include approximately 3.2% to 3.5% of carbon (C), approximately 2.11% to 2.5% of silicon (Si), approximately 0.62% to 1.0% of manganese (Mn), approximately 0.77% to 1.0% of chromium (Cr), approximately 0.2% to 0.45% of copper (Cu), approximately 0.15% to 0.3% of phosphor (P), approximately 0.035% to 0.06% of boron (B), approximately 0.07% to 0.096% of sulfur (S), and approximately 0.038% or more of titanium (Ti) by weight ratio, and iron (Fe) and any inevitable impurity comprising the remainder. 
     
     
         17 . The method of  claim 6 , wherein the raw materials include approximately 3.2% to 3.38% of carbon (C), approximately 2.2% to 2.34% of silicon (Si), approximately 0.66% to 1.0% of manganese (Mn), approximately 0.77% to 0.842% of chromium (Cr), approximately 0.35% to 0.45% of copper (Cu), approximately 0.069% to 0.3% of phosphor (P), approximately 0.035% to 0.043% of boron (B), approximately 0.083% to 0.096% of sulfur (S), and approximately 0.035% or more of titanium (Ti) by weight ratio, and iron (Fe) and any inevitable impurity comprising the remainder.