Patent Publication Number: US-2017350354-A1

Title: Pulse damper

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of International Application No. PCT/US2016/019485 filed Feb. 25, 2016, which claims priority to U.S. Provisional Application No. 62/121,258 filed on Feb. 26, 2015, which is incorporated by reference in its entirety as if set forth herein. 
    
    
     FIELD 
     The present disclosure relates generally to pulse dampers and more particularly to a pulse damper configuration on an automobile fuel system. 
     BACKGROUND 
     Pulse dampers are used to minimize periodic increases and decreases in pressure in a gas or liquid handling device. In one application, pulse dampers are used in automobile fuel systems to reduce pressure amplitude that may lead to unwanted sound transmitted to a vehicle exterior or passenger compartment. In addition, pulse dampers are used as a mechanism to reduce load transmittal to mating components such as brackets and fuel injectors. Furthermore, pulse dampers are used to maintain fuel delivery pressure for improved engine crank times. While current pulse dampers are generally satisfactory for their intended purpose, a need in the art exists to provide an improved pulse damper. 
     The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure. 
     SUMMARY 
     A pulse damper constructed in accordance to one example of the present disclosure includes a first housing member, a second housing member, a diaphragm and a valve. The first housing member defines a fuel chamber at an internal space thereof. The first housing member can further have a fuel inlet and a fuel outlet. The second housing member can define a pressurized chamber. The diaphragm can be disposed between the first and second housing. The diaphragm separates the fuel chamber and the pressurized chamber. The valve can be disposed on the second housing and be configured to selectively pass air into and out of the pressurized chamber corresponding to a desired predetermined pressure within the pressurized chamber. Increased pressure within the pressurized chamber will resist movement of the diaphragm into the pressurized chamber. 
     According to other features, the valve is a Schrader valve. A crimp ring can couple the first and second housings together. The crimp ring can sealingly couple the first and second housings together with the diaphragm sandwiched therebetween. The second housing member can be dome shaped. The first and second housing members can be formed of steel. In another configuration, the second housing member can be formed of plastic. The first housing member can be formed of plastic. The first gasket can be disposed between the first housing and the diaphragm. The second gasket can be disposed between the second housing and the diaphragm. The valve can further comprise a threaded stem having a removably coupled cap. The diaphragm can be formed of Polyimide film. The crimp ring can be formed of one of steel and aluminum. 
     A pulse damper constructed in accordance to another example of the present disclosure includes a plastic first housing member, a plastic second housing member and a diaphragm. The plastic first housing member defines a fuel chamber at an internal space thereof. The first housing member can further have a fuel inlet and a fuel outlet. The plastic second housing member can define a pressurized chamber. The diaphragm can be disposed between the first and second housing and can separate the fuel chamber and the pressurized chamber. 
     According to additional features, the pulse damper can further comprise a crimp ring that couples the first and second housings together. The crimp ring can sealingly couple the first and second housing together with the diaphragm sandwiched therebetween. The second housing member can be dome shaped. A first gasket can be disposed between the first housing and the diaphragm. The second gasket can be disposed between the second housing and the diaphragm. The diaphragm can be formed of Polymide film. The crimp ring can be formed of one of steel and aluminum. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG. 1  is a perspective view of a pulse damper constructed in accordance with one example of the present disclosure; 
         FIG. 2  is a sectional view of the pulse damper of  FIG. 1  taken along lines  2 - 2 ; 
         FIG. 3  is a sectional view of the pulse damper of  FIG. 1  taken along lines  3 - 3 ; 
         FIG. 4  is a perspective view of a pulse damper constructed in accordance to another example of the present disclosure; 
         FIG. 5  is a sectional view of the pulse damper of  FIG. 4  taken along lines  5 - 5 ; 
         FIG. 6  is an exploded view of the pulse damper of  FIG. 4 ; 
         FIG. 7  is a cross-sectional view of a pulse damper according to one example of; 
         FIG. 8  is a plot illustrating engine speed versus time for a fuel supply line without a pulse damper and for a fuel supply line with a pulse damper; 
         FIG. 9  shows a comparison of a first plot illustrating a diesel system having 1400 rpm fuel pump velocity without a pulse damper and a second plot illustrating a diesel system having a pulse damper; 
         FIG. 10  is an exploded view of a pulse damper constructed in accordance to another example of the present disclosure; 
         FIG. 11  is a cross-sectional view of the pulse damper of  FIG. 10  shown in an assembled position; 
         FIG. 12  is a cross-sectional view of the pulse damper of  FIG. 10  shown prior to crimping a crimp ring; 
         FIG. 13  is a front view of the pulse damper of  FIG. 10  and shown in an assembled position; 
         FIG. 14A  shows a pulse damper having a 0.8 mm thick steel crimp ring according to other examples of the present disclosure; and 
         FIG. 14B  shows a pulse damper having a 1.6 mm thick crimp ring constructed of either 304 stainless steel or 1010 steel. 
     
    
    
     DETAILED DESCRIPTION 
     With initial reference to  FIGS. 1-3 , a pulse damper constructed in accordance to one example of the present disclosure is shown and generally identified at reference numeral  10 . The pulse damper  10  can generally include a first housing member  12 , a second housing member  14 , a diaphragm  20 , a valve  22  and a crimp ring  26 . In some examples the crimp ring  26  can be integrally formed with the first or second housing member  12 ,  14 . In other examples, the crimp ring  26  may be separately formed. The first housing member  12  can include a fuel inlet  30  and a fuel outlet  32 . The fuel inlet  30  and the fuel outlet  32  can take the shape of ribbed fittings or other structures. 
     The first housing member  12  defines a fuel chamber  40  at an internal space thereof. The second housing member  14  defines a pressurized chamber  42 . The diaphragm  20  can be disposed between the first and the second housing members  12  and  14 . The diaphragm  20  can separate the fuel chamber  40  and the pressurized chamber  42 . In general, as fuel is passed from the fuel inlet  30  to the fuel outlet  32 , pressure can act against the diaphragm  20  in a direction generally from the fuel chamber  40  into the pressurized chamber  42 . The diaphragm  20  can move and as a result mitigate pressure amplitude. 
     The pulse damper  10  according to the present disclosure includes the valve  22 . The valve  22  can be used to selectively pass air into and out of the pressurized chamber  42 . As can be appreciated, more air in the pressurized chamber  42  will tend to resist movement of the diaphragm  20  toward the pressurized chamber  42 . In this regard, a user can set the pressurized chamber  42  to have a predetermined pressure suitable for a given application. The valve  22  can be a Schrader valve. A cap  50  can be removably secured to a corresponding threaded stem  52 . Other configurations are contemplated. 
     Turning now to  FIGS. 4-6 , a pulse damper constructed in accordance to another example of the present disclosure is shown and generally identified at reference  110 . The pulse damper  110  can generally include a first housing member  112 , a second housing member  114 , a diaphragm  120 , and a crimp ring  126 . The crimp ring  126  may be separately formed. The first housing member  112  can include a fuel inlet  130  and a fuel outlet  132 . The fuel inlet  130  and the fuel outlet  132  can take the shape of ribbed fittings or other structures. As will become appreciated from the following discussion, the first and second housing members  112  and  114  are formed out of plastic. The first and second housing members  112  and  114  can be injection molded. The diaphragm  120  can be overmolded. The plastic first and second housing members  112  and  114  can reduce weight and costs while still performing at high levels. The crimp ring  126  can be formed of metal such as steel or aluminum. 
     The first housing member  112  defines a fuel chamber  140  at an internal space thereof. The second housing member  114  defines a pressurized chamber  142 . The diaphragm  120  can be disposed between the first and the second housing members  112  and  114 . The diaphragm  120  can separate the fuel chamber  140  and the pressurized chamber  142 . In general, as fuel is passed from the fuel inlet  130  to the fuel outlet  132 , pressure can act against the diaphragm  120  in a direction generally from the fuel chamber  140  into the pressurized chamber  142 . The diaphragm  120  can move and as a result mitigate pressure amplitude. A first gasket  146  can be disposed between the first housing  112  and the diaphragm  120 . A second gasket  148  can be disposed between the second housing  114  and the diaphragm  120 . The first and second gaskets  146  and  148  can be formed of fluorocarbon. The diaphragm  120  can be formed of Polyimide film. In other examples, the first and second housing members  12  and  14  of the pulse damper  10  can be formed of plastic. 
     With reference now to  FIG. 7 , an exemplary pulse damper constructed in accordance to prior art is shown and generally identified at reference  210 . The pulse damper  210  generally includes a first housing member  212 , a second housing member  214 , a diaphragm  220 , and a crimp ring  226 . The crimp ring  226  may be integrally formed with one of the first or second housing members  212 ,  214  or separately formed. The first housing member  212  can include a fuel inlet  230  and a fuel outlet  232 . The fuel inlet  230  and the fuel outlet  232  can take the shape of ribbed fittings or other structures. 
     The first housing member  212  defines a fuel chamber  240  at an internal space thereof. The second housing member  214  defines a pressurized chamber  242 . The diaphragm  220  can be disposed between the first and the second housing members  212  and  214 . The diaphragm  220  can separate the fuel chamber  240  and the pressurized chamber  242 . In general, as fuel is passed from the fuel inlet  230  to the fuel outlet  232 , pressure can act against the diaphragm  220  in a direction generally from the fuel chamber  240  into the pressurized chamber  242 . The diaphragm  220  can move and as a result mitigate pressure amplitude. 
       FIG. 8  is a plot illustrating engine speed versus time for a fuel supply line having a pulse damper compared to a fuel supply line without a pulse damper. As shown, the plot with the pulse damper provides improved pressure mitigation.  FIG. 9  shows a comparison of a first (baseline) plot illustrating a diesel system having 1400 rpm fuel pump velocity without a pulse damper (left) and a second plot illustrating a diesel system having a pulse damper (right). Similar improved results can be attained with other RPMs. Those skilled in the art will appreciate that 1400 RPM is used for exemplary purposes. 
     The pulse dampers disclosed herein can be used as pressure accumulators. The accumulator can function to provide high pressure gasoline direct injection (GDI). The accumulator can compensate for injector leakage, fuel thermal expansion and contraction. The accumulator can inhibit long-cranking engine starts. 
     The pulse damper disclosed herein provides many advantages over prior art offerings. The pressure on the non-fuel side (pressurized chamber  42 ) can be varied to meet application requirements for pressure pulsation magnitude. The pressure at which a customer has determined to meet all requirements can then be built into the production level damper.  FIG. 10  is an exploded view of the pulse damper  110  described above with respect to  FIGS. 4-6  and prior to forming of the crimp ring  126 . Of note, in one configuration, the crimp ring  126  can have a first annular lip  152  and an upright radial wall  154 . In some examples, the second housing  114 , the first gasket  146 , the diaphragm  120 , the second gasket  148  and the first housing member  112  can be advanced to a position within an inner diameter boundary of the upright radial wall  154  during assembly to a position shown in  FIG. 12 . Subsequently, an upper portion  162  of the crimp ring  126  can be deformed up and around a rim portion  166  of the first housing member  112  capturing the respective components. 
       FIG. 14A  shows the pulse damper  110  wherein the crimp ring  126  has a thickness  180 . The thickness  180  can be 0.8 mm.  FIG. 14B  shows a pulse damper  310  wherein a crimp ring  326  has a thickness of  380 . Like reference numerals from the damper  110  increased by  200  are used for the damper  310  shown in  FIG. 14B . The thickness  380  can be 1.6 mm. The crimp rings  126  and  326  can be formed of either 304 stainless steel or 1010 steel. 
     The foregoing description of the examples has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular example are generally not limited to that particular example, but, where applicable, are interchangeable and can be used in a selected example, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.