Abstract:
A pressure regulator includes a housing, a divider including a first valve member, and a second valve member. The housing includes an inlet and an outlet, and defines an interior volume. The divider separates the interior volume into first and second chambers, and included the first valve member, a diaphragm, and a retainer. The diaphragm extends between the housing and the first valve member. Fluid communication between the first and second chambers through the diaphragm being prevented. The retainer secures the diaphragm relative to the first valve member, and the retainer is press-fitted with respect to the first valve member. The second valve member is arranged between first and second configurations relative to the first valve member. The first configuration substantially prevents fluid communication between the inlet and the outlet, and the second configuration permits fluid communication between the inlet and the outlet.

Description:
CROSS REFERENCE TO CO-PENDING APPLICATIONS 
   This application claims the benefit of the earlier filing date of U.S. Provisional Application No. 60/386,604, filed Jun. 6, 2002, the disclosure of which is incorporated by reference herein in its entirety. 

   FIELD OF THE INVENTION 
   A fuel pressure regulator relieves over-pressure in a fuel supply line between a fuel tank and an internal combustion engine. In particular, the fuel pressure regulator is responsible for supplying fuel, at or below a selected pressure, to a fuel injector of the internal combustion engine. 
   BACKGROUND OF THE INVENTION 
   Most modern automotive fuel systems utilize fuel injectors to deliver fuel to the engine cylinders for combustion. The fuel injectors are mounted on a fuel rail to which fuel is supplied by a pump. The pressure at which the fuel is supplied to the fuel rail must be metered to ensure the proper operation of the fuel injectors. Metering is carried out using pressure regulators that control the pressure of the fuel in the system at all engine r.p.m. levels. 
   Referring to  FIG. 5 , there is illustrated a known flow-through type pressure regulator  10  having a first cup shaped cover  12  and a second cup shaped cover  14  that are crimped together to form an unitary hollow member. In the axially aligned center of the enclosed end  16  of the first cover  12  is an outlet port  18  wherein fuel flows out of the regulator  10 . Around the bottom  20  of the enclosed end  22  of the second cover  14  is located at least one fuel inlet aperture  24  for receiving fuel into the regulator  10 . 
   The known flow-through type pressure regulator includes a bias means such as a spring  30  that functions to bias a valve seat member  36  of the regulator  10  at a predetermined amount of pressure that relates to the pressure desired by the regulator. One end of the spring  30  is located in a spring retainer  34  that is secured to a portion of the valve seat member  36  that extends through a central aperture  38  in a diaphragm  40 . The diaphragm  40  is supported around its circumference on a circumferential flange  42  radially extending from the open end  44  of the second cover  14  and is crimped between a circumferential flange  46  extending radially outward of the open end  48  of the first cover  12 . At the enclosed end  22  of the second cover  14  is a valve  50  that is secured to the second cover  14 . 
   According to the known flow-through pressure regulator, the spring retainer is staked to the valve seat member  36 . It is believed that the known flow-through type pressure regulator, as well as other types of pressure regulators, suffer from a number of disadvantages including a manufacturing process that requires additional assembly operations as well as tooling to perform the staking. 
   Thus, it is believed that there is a need to provide pressure regulators, e.g., of the flow-through and by-pass valve types, that overcome the disadvantages of the known pressure regulators. 
   SUMMARY OF THE INVENTION 
   The present invention provides a pressure regulator. The pressure regulator includes a housing, a divider including a first valve member, and a second valve member. The housing includes an inlet and an outlet, and defines an interior volume. The divider separates the interior volume into first and second chambers, and included the first valve member, a diaphragm, and a retainer. The diaphragm extends between the housing and the first valve member. Fluid communication between the first and second chambers through the diaphragm being prevented. The retainer secures the diaphragm relative to the first valve member, and the retainer is press-fitted with respect to the first valve member. The second valve member is arranged between first and second configurations relative to the first valve member. The first configuration substantially prevents fluid communication between the inlet and the outlet, and the second configuration permits fluid communication between the inlet and the outlet. 
   The present invention also provides a pressure regulator. The pressure regulator includes a housing that defines an interior volume, a divider that separates the interior volume into first and second chambers, and two valve member that are arranged between first and second configurations relative to one another. The housing includes a first housing portion that includes an inlet, a second housing portion, and an outlet. The divider includes a first one of the valve members, a diaphragm that extends between the housing and the first one of the valve members, and a retainer that secures the diaphragm relative to the first one of the valve members. The retainer is press-fitted with respect to the first one of the valve members. The first configuration of the two valve members substantially prevents fluid communication between the inlet and the outlet, and the second configuration of the two valve members permits fluid communication between the inlet and the outlet. Fluid communication through the diaphragm is prevented. 
   The present invention also provides a method of manufacturing a flow-through pressure regulator. The flow-through pressure regulator includes a first valve element that is mounted in a housing, a second valve elements that is movable with respect to the first valve element, and a divider that separates the housing into first and second chambers and supports the second valve element relative to the housing. The housing has an inlet and an outlet. A first configuration of the second valve element prevents a flow of fluid between the inlet and an outlet, and a second configuration of the second valve element permits the flow of fluid between the inlet and an outlet. The method includes assembling the divider and mounting the divider in the housing. The assembling the divider includes positioning a diaphragm with respect to the second valve element, and press-fitting a retainer with respect to the second valve element. The press-fitting includes sandwiching the diaphragm between the second valve element and the retainer. And the mounting the divider in the housing separates the first and second chambers. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate presently preferred embodiments of the invention, and, together with the general description given above and the detailed description given below, serve to explain features of the invention. 
       FIG. 1  is a partial cross-section view of a flow-through type pressure regulator according to a first preferred embodiment that includes a spring retainer that is press-fit with a seat. 
       FIG. 2  is a partial cross-section view of a flow-through type pressure regulator according to a second preferred embodiment that includes a spring retainer that is press-fit with a seat. 
       FIG. 3  is a partial cross-section view of a flow-through type pressure regulator according to a third preferred embodiment that includes a spring retainer that is press-fit with a seat. 
       FIG. 4  is a partial cross-section view of a by-pass valve type pressure regulator according to a fourth preferred embodiment that includes a spring retainer that is press-fit with a seat. 
       FIG. 5  is a cross-section view of a known flow-through pressure regulator that includes a spring retainer that is staked to a seat. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to  FIG. 1 , there is illustrated a flow through pressure regulator  100  having a first cup shaped cover  12  and a second cup shaped cover  14  that are crimped together to form an unitary hollow member. In the axially aligned center of an enclosed end  16  of the first cover  12  is an outlet port  18  wherein fuel flows out of the regulator  10 . The outlet port  18  is turned upward forming a tubular exit port  90 , the length or height of which functions to alter the back pressure in the regulator  100 , which affects the amount of flow through the pressure regulator  100 . Around a bottom  20  of an enclosed end  22  of the second cover  14  is located at least one fuel inlet aperture  24  for receiving fuel into the regulator  10 . 
   The first cover  12  has a dimpled center portion  26  in the enclosed end  16  forming the fuel outlet port  18  and a spring locator means  28 . A bias means such as a spring  30  functions to bias the valve seat member  36  of the regulator  10  at a predetermined amount of pressure that relates to the pressure desired by the regulator. One end of the spring  30  is located in a spring retainer  34  that is secured to a portion of the valve seat member  36  that extends through a central aperture  38  in a diaphragm  40 . The diaphragm  40  is supported around its circumference on a circumferential flange  42  radially extending from the open end  44  of the second cover  14  and is crimped between a circumferential flange  46  extending radially outward of the open end  48  of the first cover  12 . Preferably, the flange  42  of the second cover  14  is rolled-over the circumferential edge of the first cover  12  and crimped to form the unitary member. At the enclosed end  22  of the second cover  14  is a valve  50  that is secured to the second cover  14 . 
   Both the first  12  and second  14  covers are essentially cup shaped tubular members which are closed at one end and opened at the other end forming a first chamber  52  in the first cover  12  and a second chamber  54  in the second cover  14 . 
   Mounted in the central aperture  38  of the diaphragm  40  is the valve seat member  36  that is secured to the diaphragm by means of the spring retainer  34 . The diaphragm  40  forms the boundary between the first  52  and second  54  chambers. The valve seat member  36  has a central flow through passageway  58  that is open into the first  52  or outlet chamber formed in the first cover  12 . At the other end of the passageway  58  is a sealing surface on which is seated another valve member  50 , which preferably includes a spherical ball  64 . This end of the valve seat member  36  opens into the second  54  or inlet chamber. In the manufacturing of the valve seat member  36 , the sealing surface can be coined to assure a smooth sealing surface for the ball  64 . 
   The ball valve actuator  64  is located in a conical chamber  70  of the valve  50 . At the bottom  72  of the conical chamber  70  is an enclosed tubular bore  74  opening. This conical chamber  70  is sized so as to not interfere with the movement of the ball  64 . The ball  64  is retained by a ball retainer  76  that is preferably a washer shaped member  77  that has a central aperture that is somewhat smaller than the diameter of the ball  64 . Preferably, this central aperture is coined to prevent a rough surface contacting the ball  64 . At the wide end  80  of the conical chamber  70  there is formed a pocket. The washer shaped member  77  has an outside diameter that is smaller than the diameter of the pocket and is retained in the axial direction by crimping of the upper edge  84  over the washer shaped member  77 . The ball retainer  76  is not held tightly in the pocket at the end of the conical chamber  70 , but is free to move both axially and radially in the pocket. 
   In the enclosed tubular bore  74 , a light bias spring  86  is positioned to move the ball  64  in an axial direction away from the bottom  72  of the conical chamber  70 . The spring  86  biases the ball  64  and the ball retainer  76 , which is located above the major diameter of the ball or its horizontal axis, against the inside of the upper edge  84 . 
   The spring  86  functions to bias the ball  64  against the sealing surface of the valve seat member  36 . When the pressure at the inlet fuel is greater than the force exerted by the large bias spring  30 , the diaphragm  40  moves in an axial direction and the ball  64  leaves the valve seat member  36 . Fuel can then flow through the regulator  10  until the pressure of the large bias spring  30  is strong enough to return the valve seat member  36  to the ball  64  surface, thus closing the passageway  58  in the valve seat member  36 . 
   The material of the several part of the fuel regulator is preferably stainless steel or some similar material which resists corrosion due to the nature of the fuel. 
   According to the first preferred embodiment shown in  FIG. 1 , the spring retainer  34  includes a cap like diaphragm-to-seat retainer that is press-fit over the seat  36  of the flow-through type regulator  100 . An undercut on the surface  36   a  of the seat  36  grabs onto the spring retainer  34 , and along with the force of the press-fit, holds the spring retainer  34  in place with respect to the seat  36 . 
   According to the second preferred embodiment shown in  FIG. 2 , the spring retainer  34  includes a ring-like diaphragm-to-scat retainer that is press-fit over the seat  36  of a flow-through type regulator  200 . According to the regulator  200 , the spring retainer  34  is held in place with respect to the surface of the seat  36  by the force of the press-fit. 
   A weld, e.g., a laser weld, between an end surface of the spring retainer  34  and the surface of the seat  36  may provide additional strength to the coupling between the spring retainer  34  and the seat  36 . 
   According to the third preferred embodiment shown in  FIG. 3 , a flow-through type regulator  300  includes a ring like diaphragm-to-seat spring retainer  34  that is pressed over an undercut on the surface of the seat  36 . The spring retainer  34  snaps into the undercut edge and is held in place thereby with respect to the seat  36 . 
   According to the fourth preferred embodiment shown in  FIG. 4 , the spring retainer  34  includes a ring-like diaphragm-to-valve member spring retainer that is press-fit over the valve  50  of a by-pass valve type pressure regulator  400 . According to the regulator  400 , the spring retainer  34  is held in place with respect to the surface of the valve  50  by the force of the press-fit. Additionally, an undercut  50   a  on the surface of the valve  50  grabs onto the spring retainer  34 , and along with the force of the press-fit, holds the spring retainer  34  in place with respect to the valve  50 . Preferably, fluid flow through the by-pass valve type regulator  400  passes in  424  via an inlet formed in the second cover  14 , between the valve  50  and the seat (not shown), and then passes out  418  through an outlet that is also formed in the second cover  14 . 
   One method of assembling the pressure regulator  100 , 200 , 300 , 400  is to assemble the spring retainer  34 , valve seat member  36  (per  FIGS. 1–3 ) or valve  50  (per  FIG. 4 ), and diaphragm  40  into a divider unit. The assembled unit, along with the spring  30 , is mounted between the first and second covers  12 , 14 . According to the present invention, the spring retainer  34  is press-fitted with respect to either the valve seat member  36  or the valve  50 . 
   Preferably, the divider unit is assembled by installing central aperture  38  of the diaphragm  40  around the valve seat member  36 , so as to surround the passageway  58 , and press fitting the spring retainer  34  onto the valve seat member  36  so as to sealingly sandwich therebetween the diaphragm  40 . The valve seat member  36  may also include an undercut edge into which the spring retainer  34  snaps so as to hold the spring retainer  34  in place with respect to the valve seat member  36 . 
   And as shown in  FIG. 4 , the arrangement of the valve seat member  36  and the valve  50  may be reversed such that the diaphragm  40  and the spring retainer  34  are press-fitted with respect to the valve  50 , and the valve seat member is generally fixed to the first cover  12 . 
   The spring  30  is installed in the second cover  14 . Preferably, a first end of the spring  30  is positioned with respect to the second cover  14 , and a second end of the spring  30  is positioned with respect to the spring retainer  34 . 
   The first and second covers  12 , 14  are then matingly engaged. Preferably, the flanges  42 , 46  of the first and second covers  12 , 14  are abutted against one another and then crimped together. Of course, other coupling techniques, e.g., welding or adhering, may be used to secure the first and second covers  12 , 14  with respect to one another. 
   The operation of the flow-through pressure regulator  100 , 200 , 300  in a fuel system will now be described. The spring  30  acts through the spring retainer  42  to bias the divider unit toward the valve  50 . In a first configuration, the sphere  64  is seated against the valve seat member  36  so as to prevent a flow of fuel through the passage  58 , and thus through the pressure regulator  100 , 200 , 300 , 400 . 
   Fuel enters the regulator  100 , 200 , 300  through fuel inlet aperture(s)  24  and exerts pressure on the divider unit. When the force of the fuel pressure acting on the divider unit is greater than the force exerted by the spring  30 , the diaphragm  40  flexes so as to allow the valve seat member  36  to move along the longitudinal axis A, and the sphere  64  separates from the valve seat member  36 . This is a second configuration that permits the flow of fuel through fuel inlet aperture(s)  24 , between the sphere  64  and the valve seat member  36 , through the passage  58 , and through the fuel outlet port  18 . Selection of the spring  30 , and more particularly the force exerted by the spring  30  on the divider unit, determines the fuel pressure level at which pressure regulation, i.e., the transition between the first and second configurations, occurs in the pressure regulator  100 , 200 , 300 . 
   The operation of the by-pass valve type pressure regulator  400  is similar except that the first and second valve elements are reversed with respect to the housing and the diaphragm, and the fluid in  424  and out  418  through the second cover  14 . 
   A spring retainer that is press-fitted with respect to the valve seat member or valve  50 , according to the present invention, eliminates the staking operations that were necessary in known flow-through pressure regulators. Thus, the disadvantages associated with staking, e.g., the need to frequently replace the staking tools due to damage and wear, are eliminated. Accordingly, the present invention provides an easier and more cost-effective way of assembling a flow-through pressure regulator. 
   While the invention has been disclosed with reference to certain preferred embodiments, numerous modifications, alterations, and changes to the described embodiments are possible without departing from the sphere and scope of the invention, as defined in the appended claims and their equivalents thereof. Accordingly, it is intended that the invention not be limited to the described embodiments, but that it have the full scope defined by the language of the following claims.