Push-on fuel cap

Abstract

According to the present invention, a push-on cap is provided for engaging a filler neck. The cap includes .[.means.]. .Iadd.member .Iaddend.for closing the mouth of the filler neck. This closing .[.means.]. .Iadd.member .Iaddend.includes a housing and an end member which is coupled to the housing while being axially movable relative to the housing. The cap further includes .[.means.]. .Iadd.a mechanism .Iaddend.for gripping the filler neck in response to the sliding axially inward movement between a filler neck-engaging position and a filler neck-disengaging position.

We claim: 
     
       1. A cap engageable with a filler neck having a mouth and a seal seat disposed axially inwardly from said mouth internally in said filler neck, the cap comprising means for closing the mouth of the filler neck, the closing means including a housing and an end closure member coupled to the housing, the end closure member being axially movable relative to the housing and having a sealing ring configured to engage the seal seat upon slidable insertion of the housing into the filler neck in an axially inward cap-installation direction, .[.and.].   means for gripping the filler neck in response to sliding axially inward movement of the housing in the filler neck, the gripping means being mounted in the housing for movement between a filler neck-engaging position and a filler neck-disengaging position.[...]..Iadd.,.Iaddend.   .Iadd.a handle cover rotatably coupled to the housing, and   a core coupled to the gripping means and to the handle cover so that the core rotates in the housing in response to rotational movement of the handle relative to the filler neck to move the gripping means in a radially inward direction relative to the housing to the filler neck-disengaging position..Iaddend..[.   
     
     
       2.  The cap of claim 1, further comprising means for moving the gripping means to the filler neck-disengaging position..]. 
     
     
       3. .[.The cap of claim 2, wherein.]. .Iadd.A cap engageable with a filler neck having a mouth and a seal seat disposed axially inwardly from said mouth internally in said filler neck, the cap comprising means for closing the mouth of the filler neck, the closing means including a housing and an end closure member coupled to the housing, the end closure member being axially movable relative to the housing and having a sealing ring configured to engage the seal seat upon slidable insertion of the housing into the filler neck in an axially inward cap-installation direction,   means for gripping the filler neck in response to sliding axially inward movement of the housing in the filler neck, the gripping means being mounted in the housing for movement between a filler neck-engaging position and a filler neck-disengaging position,   means for moving the gripping means to the filler neck-disengaging position, .Iaddend.the moving means .[.includes.]. .Iadd.including .Iaddend.a core rotatably coupled in the housing, a cam follower appended to the gripping means, and a cam formed in the core, and the cam includes means for contacting the cam follower through a pre-determined arc of rotation of the core to move the gripping means in a radially inward direction relative to the filler neck permitting movement of the housing in an axially outward cap-disengagement direction. .[.4. The cap of claim 2, wherein the moving means includes a handle cover and means for coupling the handle cover to the gripping means so that the gripping means is moved in a radially inward direction relative to the housing in response to   
     
     
        rotational movement of the handle cover relative to the filler neck..].5. .[.The cap of claim 4, wherein.]. .Iadd.A cap engageable with a filler neck having a mouth and a seal seat disposed axially inwardly from said mouth internally in said filler neck, the cap comprising means for closing the mouth of the filler neck, the closing means including a housing and an end closure member coupled to the housing, the end closure member being axially movable relative to the housing and having a sealing ring configured to engage the seal seat upon slidable insertion of the housing into the filler neck in an axially inward cap-installation direction,   means for gripping the filler neck in response to sliding axially inward movement of the housing in the filler neck, the gripping means being mounted in the housing for movement between a filler neck-engaging position and a filler neck-disengaging position, and   means for moving the gripping means to the filler neck-disengaging position, the moving means including a handle cover and means for coupling the handle cover to the gripping means so that the gripping means is slidably moved in the radial direction relative to the housing in response to rotational movement of the handle cover relative to the filer neck, and .Iaddend.the gripping means includes three spring-loaded latches positioned in spaced-apart relation about the circumference of the housing and the coupling means includes a core positioned in the housing and configured to rotatably actuate the latches in response to rotational   
     
     
        movement of the handle cover relative to the filler neck. 6. The cap of claim .[.4.]..Iadd.1.Iaddend., wherein the handle cover includes a base and means for movably mounting the base on the housing so that the base 
     
     
        rotates independently of the housing. 7. The cap of claim 6, wherein the housing includes a cylindrical wall defining a cavity therein, an outer wall, an inner wall, a support platform .[.being.]. mounted to the inner wall and extending in a radial direction across the cavity, and a rod mounted to the support platform .Iadd.and .Iaddend.extending in an axially outward direction, the latch includes an inside portion and an outside portion, and the .[.yielding.]. .Iadd.allowing .Iaddend.means includes a spring extending through the cavity .Iadd.and positioned to lie 
     
     
        .Iaddend.between the inside portion of the latch and the rod. 8. The cap of claim 1, wherein the gripping means includes a latch and means for yieldably allowing passage of the latch in .[.the.]. .Iadd.a .Iaddend.radially inward direction in response to the sliding axially 
     
     
        inward movement of the housing in the mouth of the filler neck. 9. The cap of claim 8, wherein the .[.yielding.]. .Iadd.allowing .Iaddend.means includes means for snapping the latch in a radially outward direction 
     
     
        relative to the housing for engagement with the filler neck. 10. The cap of claim 1, wherein the housing includes a cylindrical wall extending in the axially inward direction, the wall .[.being.]. .Iadd.is .Iaddend.formed to include an aperture, and the gripping means extends 
     
     
        through the aperture. 11. The cap of claim 10, wherein the gripping means is a latch having an inside portion positioned in the housing, an outside portion extending from the aperture outside the housing, and means for aiding radially inward movement of the outside portion through the aperture in response to pushing the latch into the mouth of the filler 
     
     
        neck. 12. The cap of claim 1, wherein the housing is formed to include means for supporting the gripping means and a mounting body extending downward from the supporting means, the mounting body having means for 
     
     
        yieldably engaging the end closure member. 13. The cap of claim 12, wherein the end closure member includes a cup-shaped mouth having an engagement lip, the mounting body extends into the cup-shaped mouth and 
     
     
        the engagement lip interacts with the engagement means. 14. .[.The cap of claim 1, wherein.]. .Iadd.A cap engageable with a filler neck having a mouth and a seal seat disposed axially inwardly from said mouth internally in said filler neck, the cap comprising means for closing the mouth of the filler neck, the closing means including a housing and an end closure member coupled to the housing, the end closure member being axially movable relative to the housing and having a sealing ring configured to engage the seal seat upon slidable insertion of the housing into the filler neck in an axially inward cap-installation direction, (and)   means for gripping the filler neck in response to sliding axially inward movement of the housing in the filler neck, the gripping means being mounted in the housing for sliding movement in a radial direction between a filler neck-engaging position and a filler neck-disengaging position, and .Iaddend.the filler neck includes an internal flange and the housing includes means for contacting the internal flange to permit axial movement of the housing into and out of the filler neck and to block rotation of   
     
     
        the housing relative to the filler neck. 15. The cap of claim 14, wherein the housing includes an outer wall and an inner wall, and the contacting 
     
     
        means is a rib formed on the outer wall. 16. The cap of claim 15, wherein the rib includes means for inhibiting rotation of the end closure member relative to the filler neck during axial movement of the housing into and 
     
     
        out of the filler neck. 17. The cap of claim 1, wherein the housing includes a cylindrical wall defining a cavity extending therein, an inner wall, an outer wall, a support platform .[.being.]. mounted to the inner wall and extending in a radial direction across the cavity, and a rod mounted to the support platform .Iadd.and .Iaddend.extending in an axially outward direction and the gripping means includes a latch being seated on the support platform and a spring extending between the latch and the rod. 
     
     
        8. The cap of claim 17 further comprising a cam follower positioned on an outward side of the latch and .[.a.]. .Iadd.the .Iaddend.core .[.being.]. .Iadd.is .Iaddend.formed to include a central aperture, an interior end and an exterior end relative to the mouth of the filler neck, and a cam formed in the interior end, the rod extending through the central aperture, the interior end of the core engaging the outward side of the 
     
     
        latch, and the cam follower extends for engagement with the cam. 19. The cap of claim 18, wherein the core further includes a hub extending in an axially outward direction from the .[.external.]. .Iadd.exterior 
     
     
        .Iaddend.end. 20. .[.The cap of claim 19, further comprising.]. .Iadd.A cap engageable with a filler neck having a mouth and a seal seat disposed axially inwardly from said mouth internally in said filler neck, the cap comprising means for closing the mouth of the filler neck, the closing means including a housing and an end closure member coupled to the housing, the end closure member being axially movable relative to the housing and having a sealing ring configured to engage the seal seat upon slidable insertion of the housing into the filler neck in an axially inward cap-installation direction, the housing including a cylindrical wall defining a cavity extending therein, an inner wall, an outer wall, a support platform mounted to the inner wall and extending in a radial direction across the cavity, and a rod mounted to the support platform and extending in an axial outward direction,   means for gripping the filler neck in response to sliding axially inward movement of the housing in the filler neck, the gripping means being mounted in the housing for sliding movement in a radial direction between a filler neck-engaging position and a filler neck-disengaging position, and including a latch being seated on the support platform and a spring extending between the latch and the rod,   a cam follower positioned on an outward side of the latch nad a core formed to include a central aperture, an interior end and an exterior end relative to the mouth of the filler neck, a hub extending in an axial direction from the exterior end, and a cam formed in the interior end, the rod extending through the central aperture, the interior end of the core engaging the outward side of the latch, and the cam follower extends for engagement with the cam, and .Iaddend.a handle having a base and means for mounting the base on the hub so that the core rotates in the housing in resonse to rotational movement of the handle relative to the filler neck.   
     
     
         1. A cap engageable with a filler neck having a mouth and a seal seat disposed axially inwardly from said mouth internally in said filler neck, the cap comprising means for closing the mouth of the filler neck, the closing means including an end closure member and means for establishing a seal between the end closure member and the seal seat,   a housing movably coupled to the closing means, the housing being sized to extend into the filler neck through the mouth and formed to include a cylindrical wall having an aperture, and   means for gripping the filler neck in response to the pushing of the establishing means against the seal seat establishing a liquid fuel and vapor seal therebetween, the gripping means being .[.formed.]. .Iadd.positioned .Iaddend.for .Iadd.sliding .Iaddend.movement .Iadd.in a radial direction .Iaddend.between a filler neck-engaging position and a filler neck-disengaging position and mounted in the housing, the gripping means including a latch and a means for snapping the latch through the aperture for engagement with the filler neck.Iadd.,   wherein the end closure member has a cup-shaped mouth extending over the housing and the cylindrical wall of the housing is formed for axial movement into the cup-shaped mouth in response to pushing the establishing   
     
     
        means against the seal seat.Iaddend.. 22. The cap of claim 21, further comprising means for releasing the liquid fuel and vapor seal, the releasing means including means for moving the latch to the filler neck-disengaging position and means for compelling movement of the housing 
     
     
        in an axially outward cap-disengagement direction. 23. The cap of claim 22, wherein the compelling means includes a compression spring extending between the housing and the end closure member so that the housing moves in the axially outward .Iadd.cap-disengagement .Iaddend.direction in response to the movement of the gripping means to the filler 
     
     
        neck-disengaging position. 24. .[.The cap of claim 22, wherein.]. .Iadd.A cap engageable with a filler neck having a mouth and a seal seat disposed axially inwardly from said mouth internally in said filler neck, the cap comprising means for closing the mouth of the filler neck, the closing means including an end closure member and means for establishing a seal between the end closure member and the seal seat,   a housing movably coupled to the closing means, the housing being sized to extend into the filler neck through the mouth and formed to include a cylindrical wall having an aperture, and   means for gripping the filler neck in response to the pushing of the establishing means against the seal seat establishing a liquid fuel and vapor seal therebetween, the gripping means being positioned for sliding movement in a radial direction between a filler nack-engaging position and a filler neck-disengaging position and mounted in the housing, the gripping means including a latch and a means for snapping the latch through the aperture for engagement with the filler neck,   means for releasing the liquid fuel and vapor seal, the releasing means including means for moving the latch to the filler neck-disengaging position and means for compelling movement of the housing in an axially outward cap-disengagement direction, .Iaddend.the moving means .[.includes.]. .Iadd.including .Iaddend.a core formed of rotational movement within the housing and means for pulling the latch through the   
     
     
        aperture when the core is rotated relative to the housing. 25. The cap of claim 24, wherein the pulling means includes a cam follower attached to the latch and means for camming the cam follower .[.for movement of.]. .Iadd.to move .Iaddend.the latch in a radially inward direction through 
     
     
        the aperture to the filler neck-disengaging position. 26. The cap of claim 25, wherein the core has an exterior end and an interior end relative to the mouth .Iadd.of the filler neck .Iaddend.and the camming means is a cam formed in the interior end and configured to extend over the cam follower. 
     
     
        7. The cap of claim 25, wherein the camming means is a cam, and the cam is formed to include means for permitting the radially inward movement of the cam follower when the latch is pushed into the mouth of the filler neck. .[.28. The cap of claim 21, wherein the end closure member has a cup-shaped mouth and the housing is formed for axial movement into the cup-shaped mouth in response to pushing the seal establishing means 
     
     
        against the seal seat..].29. The cap of claim .[.28.]..Iadd.21.Iaddend., further comprising means for yieldably allowing passage of the housing in the cup-shaped mouth, the allowing means extending between the housing and 
     
     
        the end closure member. 30. The cap of claim 29, wherein the filler neck contains a gripping portion having a flange, and the latch extends into 
     
     
        the gripping portion engaging the flange. 31. The cap of claim 30, wherein the .[.yielding.]. .Iadd.allowing .Iaddend.means further includes means for pushing the housing in an axially outward direction so that the latch is pressed against the flange securing the housing in the filler neck. 
     
     
            The cap of claim 21, wherein the cylindrical wall is formed to include three apertures and the gripping means includes three latches extending 
     
     
        through the three apertures in the filler neck-engaging position. 33. .[.The cap of claim 21 having.]. .Iadd.A cap engageable with a filler neck having a mouth and a seal seat disposed axially inwardly from said mouth internally in said filler neck, the cap comprising means for closing the filler neck, the closing means including an end closure member and means for establishing a seal between the end closure member and the seal seat,   a housing movably coupled to the closing means, the housing being sized to extend into the filler neck through the mouth and formed to include a cylindrical wall having an aperture, and   means for gripping the filler neck in response to the pushing of the establishing means against the seal seat establishing a liquid fuel and vapor seal therebetween, the gripping means being positioned for sliding movement in a radial direction between a filler nack-engaging position and a filler neck-disengaging position and mounted in the housing, the gripping means including a latch and a means for snapping the latch through the aperture for engagement with the filler neck, and .Iaddend.means for inhibiting rotation of the cylindrical wall in the   
     
     
        filler neck. 34. A cap engageable with a filler neck having a mouth and a seal seat disposed axially inwardly from said mouth internally in said filler neck, the cap comprising means for closing the filler neck, the closing means including a housing and means for establishing a seal on the seal seat, the seal means being coupled to the housing for axial movement therewith relative to the filler neck,   .Iadd.a handle cover rotatably coupled to the housing,.Iaddend.   means for gripping the filler neck in response to the pushing of the housing the mouth of the filler neck, the gripping means being mounted for .Iadd.sliding .Iaddend.movement .Iadd.in a radial direction .Iaddend.between a filler neck-engaging position and a filler neck-disengaging position and   means for moving the gripping means from the filler neck-engaging position to the filler neck-disengaging position.Iadd., the moving means including a core coupled to the gripping means and to the handle cover so that the core rotates in the housing in response to rotational movement of the handle relative to the housing to move the gripping means in a radially   
     
     
        inwardly direction to the filler neck-disengaing position.Iaddend.. 35. The cap of claim 34, wherein the moving means includes means for engaging the gripping means and means for pulling the gripping means in a 
     
     
        radially inward direction relative to the filler neck. 36. The cap of claim 35, wherein the housing is formed to include an upper lip, a cylindrical wall extending axially inwardly from said upper lip, and means for inhibiting rotation of the .Iadd.cylindrical .Iaddend.wall in the filler neck and the engaging means includes a handle and means for movably mounting the handle to the upper lip for rotational movement relative to 
     
     
        both .Iadd.of .Iaddend.the housing and .[.to the.]. filler neck. 37. .[.The cap of claim 35, wherein.]. .Iadd.A cap engageable with a filler neck having a mouth and a seal seat disposed axially inwardly from said mouth internally in said filler neck, the cap comprising means for closing the mouth of the filler neck, the closing means including a housing and means for establishing a seal on the seal seat, the seal means being coupled to the housing for axial movement relative to the filler neck,   means for gripping the filler neck in response to the pushing of the housing into the filler neck, the gripping means being mounted in the housing for sliding movement in a radial direction between a filler neck-engaging position and a filler neck-disengaging position, and   means for moving the gripping means from the filler neck-engaging position to the filler neck-disengaging position, the moving means including means for engaging the gripping means and means for pulling the gripping means in a radially inward direction relative to the filler neck and .Iaddend.the engaging means is a core mounted in the housing and the pulling means includes a cam formed in the core and means for following the cam so that the gripping means moves in the radially inward direction through the aperture in response to rotational movement of the core within   
     
     
        the housing. 38. The cap of claim 34, wherein the housing includes a cylindrical wall extending in the axially inward direction relative to the filler neck, the wall is formed to include an aperture and the gripping means extends through the aperture in the filler neck-engaging position. 
     
     
          . The cap of claim 34, wherein the filler neck is formed to include a gripping portion, the seal means includes an end closure member having a cup-shaped mouth and a seal ring coupled to the end closure member, and the gripping means includes a latch and means for snapping the latch into the gripping portion in response to pushing the housing into the 
     
     
        cup-shaped mouth of the end closure member. 40. The cap of claim 39, wherein the end closure member includes an internal wall and means for permitting yieldable sliding axially inward movement of the housing along the internal wall in response to the pressing of the seal ring on the seal seat so that the gripping means abuts the gripping portion of the filler 
     
     
        neck. 41. The cap of claim 34, wherein the housing includes a cylindrical wall defining a cavity extending therein, an inner wall, an outer wall, a support platform mounted to the inner wall and extending in a radial direction across the cavity, and a rod mounted to the support platform and extending in an axially outward direction, the gripping means includes a latch seated on the support platform and a spring extending between the latch and the rod, and the moving means .[.is.]. .Iadd.includes .Iaddend.a cam follower positioned on the latch and .[.a.]. .Iadd.the .Iaddend.core being formed to include a central aperture and a cam, the rod extends through the central aperture, and the core is seated on the latch so that 
     
     
        the cam extends over the cam follower. 42. The cap of claim 34, wherein the moving means .[.is.]. .Iadd.includes .Iaddend.a cam follower positioned on the gripping means.[., a.]. .Iadd.and the .Iaddend.core .[.having.]. .Iadd.has .Iaddend.an internal end and an external end relative to the mouth of the filler neck, and a cam formed in the internal end, the core is seated on the gripping means so that the cam extends over 
     
     
        the cam follower. 43. A cap engageable with a filler neck having a mouth and a seal seat disposed axially inwardly from said mouth internally in said filler neck, the cap comprising means for closing the mouth of the filler neck, the closing means including a housing and an end closure member coupled to the housing, the end closure member being axially movable relative to the housing and having a sealing ring configured to engage the seal seat upon slidable insertion of the housing into the filler neck in an axially inward cap-installation direction,   means for gripping the filler neck in response to sliding axially inward movement of the housing in the filler neck, the gripping means being formed for .Iadd.sidable .Iaddend.movement .Iadd.in a radial direction .Iaddend.between a filler neck-engaging position and a filler neck-disengaging position.Iadd., .Iaddend.and mounted in the housing, the gripping means includes three spring-loaded latches positioned in spaced-apart relation about the circumference of the housing, and means for moving the three .Iadd.spring-loaded .Iaddend.latches from the filler neck-engaging position to the filler neck-disengaging position, the moving means including a handle cover and means for coupling the handle cover .Iadd.relative .Iaddend.to the three spring-loaded latches so that the latches are rotatably actuated in response to rotational movement of the handle cover relative to the filler neck. .Iadd.44. A cap engageable with a vehicle filler neck having an inside wall defining a fill passageway and a seal seat disposed internally in said vehicle filler neck and extending from the inside wall into the fill passageway, the cap comprising   a housing,   an end closure member coupled to the housing and axially movable in the fill passageway relative to the housing, the end closure member carrying a seal configured to engage the seal seat upon insertion of the housing into the vehicle filler neck in an axially inward cap-installation direction,   a latch positioned to extend from the housing, the latch being formed to grip the vehicle filler neck in a filler neck-engaging position in response to pressing the seal in the axially inward cap-installation direction against the seal seat and to move to a filler neck-disengaging position,   a handle cover, and   a core coupled to the handle cover and to the latch so that the latch is rotatably actuated toward the filler neck-disengaging position in response to rotational movement of the handle cover relative to the filler neck..Iaddend..Iadd.45. The cap of claim 44, wherein the end closure member includes an internal wall and a middle support platform that extends across the internal wall..Iaddend..Iadd.46. The cap of claim 44, wherein the housing includes a wall defining a cavity extending therein, an inner wall, a support platform mounted to the inner wall and extending in a radial direction across the cavity, a rod mounted to the support platform, and a spring extending between the rod and the latch..Iaddend..Iadd.47. The cap of claim 44, wherein the housing is formed to include a wall having an aperture and the latch extends through the aperture..Iaddend..Iadd.48. A cap engageable with a vehicle filler neck having having an inside wall defining a fill passageway and a seal seat disposed internally in said vehicle filler neck and extending from the inside wall into the fill passageway, the cap comprising   a housing formed to include a wall defining a cavity extending therein, apertures extending through the wall, and a support platform mounted to the wall and extending in a radial direction across the cavity,   an end closure member coulped to the housing, the end closure member being axially movable in the fill passageway relative to the housing and carrying a seal configured to engage the seal seat upon insertion of the housing into the vehicle filler neck in an axially inward cap-installation direction and latches formed for slidable movement in a radial direction mounted on the support platform and positioned to lie in alignment with the apertures in the wall, the latches being configured to grip the vehicle filler neck following pressing engagement of the seal of the end closure member angainst the seal seat in the vehicle filler neck..Iaddend..Iadd.49. The cap of claim 48, further comprising a core rotatably coupled in the housing, a cam follower appended to each of the latches, and cams formed in the core, each cam follower contacting one of the cams through a pre-determined arc of rotation of the core in the housing and moving one of the latches in a radially inward direction relative to the vehicle filler neck to permit movement of the housing in an axially outward cap-disengagement direction..Iaddend..Iadd.50. The cap of claim 49, further comprising springs that are positioned to lie in the housing in engagement with the latches, the springs being configured to yieldably allow passage of the latches in the radially inward direction in response to the inward movement of the housing in the vehicle filler neck..Iaddend..Iadd.51. A cap engageable with a vehicle filler neck having a mouth, an inside wall defining a fill passageway, and a seal seat extending from the inside wall into the fill passageway and disposed axially inwardly from said mouth internally in said vehicle filler neck, the cap comprising   a housing sized to extend into the vehicle filer neck through the mouth,   an end closure member movably coupled to the housing,   a seal between the end closure member and the seal seat,   a latch mounted in the housing, and formed for slidable movement in a radial direction,   a spring mounted in the housing and engaging the latch, the spring being configured to snap the latch into engagement with the vehicle filler neck in respose to the pushing of the seal against the seal seat and the housing into the end closure member establishing a liquid fuel and vapor seal between the seal and seal seat..Iaddend..Iadd.52. The cap of claim 51, further comprising a compression spring that extends between the housing and the end closure member so that the housing moves in an axially outward direction in response to movement of the latch to the vehicle filler neck-disengaing position..Iaddend..Iadd.53. The cap of claim 51, wherein the end closure member has a cup-shaped mouth and the housing is formed for axial movement into the cup-shaped mouth in response to pushing   
     
     
        the seal against the seal seat..Iaddend..Iadd.54.  A cap engageable with a vehicle filler neck having a mouth, an inside wall defining a fill passageway, an a seal seat extending from the inside wall into the fill passageway and dispose axially inwardly from said mouth internally in said vehicle filler neck, the cap comprising a handle,   a housing coupled to the handle,   an end closure member having a seal to engage the seal seat, the end closure member being coupled to the housing for axial movement therewith relative to the vehicle filler neck,   a latch mounted in the housing between the handle and the end closure member and configured for slidable movement in a radial direction to grip the vehicle filler neck in response to axial movement of the housing into the mouth of the vehicle filer neck, and   a spring mounted in the housing and configured to move the latch into engagement with the filler neck in response to the seal engaging the seal seat..Iaddend..Iadd.55. The cap of claim 54, wherein the housing is formed to include an upper lip, a wall extending axially inwardly from said upper lip, and a rib mounted on the wall and configured to inhibit rotation of the wall in the vehicle filler neck..Iaddend..Iadd.56. The cap of claim 54, wherein the housing includes a cylindrical wall that has an inner wall surface defining a cavity and an outer wall surface, a support platform that is mounted to the inner wall surface and extends across the cavity, and a rod mounted to the support platform, the latch is seated on the support platform, and the spring extends between the latch and the   
     
     
        rod..Iaddend..Iadd.57.  A cap engagable with a vehicle filler neck having a mouth, an inside wall defining a fill passageway, an a seal seat extending from the inside wall into the fill passageway and dispose axially inwardly from said mouth internally in said vehicle filler neck, the cap comprising a housing formed to include a wall that has an inner wall surface defining a cavity and an outer wall surface, three spaced apart apertures extending between the outer and inner wall surfaces, a support platform mounted to the inner wall and extending across the cavity, and a rod mounted to the support platform,   an end closure member coupled to the housing, the end closure member being axially movable relative to the housing and having a seal configured to engage the seal seat upon insertion of the housing into the vehicle filler neck in an axially inward cap-installation direction,   three spaced-apart latches seated on the support platform and aligned for slidable movement in a radial direction through the three spaced-apart apertures between a vehicle filler neck-engaging position and a vehicle filler neck-disengaging position,   springs extending between the rod and the three spaced-apart latches and configured to snap the three spaced-apart latches outwardly through the three spaced-apart apertures from the vehicle filler neck-disengaging position to the vehicle filler neck-engaging position,   a cam follower coupled to each of the three spaced-apart latches,   a core positioned to lie in the cavity of the housing and formed to include a central aperture, an interior end and an exterior end relative to the vehicle filler neck, a hub extending from the exterior end, and three spaced-apart cams formed in the interior end, the rod extending through the central aperture, the interior end of the core engaging the three spaced-apart latches, and the three spaced-apart cams contacting the three spaced-apart cam followers and pull the cam followers and the three spaced-apart latches in a radially inward direction toward the vehicle filler neck-disengaging position in response to rotational movement of the core, and   a handle cover including a base engaging the core and a mount engaging the housing, the base including a core slot that is sized to receive the hub of the core therein, the hub engaging the base during rotation of the handle cover to cause rotation of the core in the cavity of the housing..Iaddend.