초록 ▼

A plug and filter assembly for a paint sprayer is characterized by a hand turnable knob that is rotatably coupled to a sealing plug to reduce the torque needed to install or remove the assembly from a paint head by axially advancing the plug into or out of an O-ring seal without having to turn the p

A plug and filter assembly for a paint sprayer is characterized by a hand turnable knob that is rotatably coupled to a sealing plug to reduce the torque needed to install or remove the assembly from a paint head by axially advancing the plug into or out of an O-ring seal without having to turn the plug in the O-ring. The rotatable coupling is effected by a fastener having a head and a cylindrical shank portion which is received in an oversized central axial bore in the knob. The cylindrical shank portion has a diameter greater than that of a threaded end portion of the fastener secured in the plug and thus defines a shoulder which engages an axial end face of the plug positively to fix the axial spacing between the fastener head and plug to a distance greater than the axial length of a portion of the knob axially trapped between the fastener head and plug for free nonbinding rotation of the knob. A filter screen is coaxially connected to the plug by a coil spring and inner and outer end caps for insertion and removal of the assembly as a unit.

대표청구항 ▼

1. A plug and filter assembly removably securable in a paint head or the like having a filter chamber and a bore for insertion and removal of the assembly, said assembly comprising: a sealing plug axially insertable into the paint head bore for sealing by an annular element to the inside of the p

1. A plug and filter assembly removably securable in a paint head or the like having a filter chamber and a bore for insertion and removal of the assembly, said assembly comprising: a sealing plug axially insertable into the paint head bore for sealing by an annular element to the inside of the paint head bore; a cylindrical filter insertable into the paint head filter chamber; means securing said filter coaxially to the inner end of said sealing plug; a knob having a threaded portion for threaded engagement with a correspondingly threaded portion of the paint head and a head portion for turning of said knob; and fastener means rotatably coupling said sealing plug and knob for axially driving of said sealing plug without rotation into and out of engagement with the sealing element upon turning of said knob when in threaded engagement with the paint head. 2. An assembly as set forth in claim 1, wherein said fastener means includes a cylindrical shank portion extending through an oversized central axial bore in said knob, a head having a diameter greater than the central bore to provide an axially inner face cooperative with an axially outer face of said knob to trap axially therebetween a portion of said knob, and a threaded end portion screwed into said plug, said threaded end portion having a diameter less than that of said cylindrical shank portion to form a shoulder which engages an axial end of said plug positively to fix the axial spacing between such inner and outer faces to a distance greater than the axial length of the trapped portion of said knob for free nonbinding rotation of said knob. 3. An assembly as set forth in claim 1, wherein said sealing plug has a cylindrical portion movable into the sealing element to compress the sealing element radially between said plug and the paint head. 4. An assembly as set forth in claim 1, wherein said threaded portion of said knob is in the form of an annular skirt extending coaxially inwardly from said head portion of said knob to define a socket for receiving an axially outer portion of said plug. 5. An assembly as set forth in claim 4, wherein said skirt is threaded at its outer diameter for threaded engagement with a correspondingly threaded portion of the paint head. 6. An assembly as set forth in claim 5, wherein there is radial clearance between said skirt and outer portion of said plug to accommodate misalignment between said knob and plug when respectively secured and sealed in the paint head. 7. An assembly as set forth in claim 1, wherein said means securing said filter includes a pair of filter end caps telescopically fitted in respective ends of said filter, one filter end cap being secured to said plug and to the other filter end cap by a coil spring. 8. In a housing having a bore, a plug assembly for sealingly closing the housing bore comprising: a plug axially insertable into the housing bore for sealing by an annular sealing element to the inside of the housing bore; a knob having a threaded portion for threaded engagement with a correspondingly threaded portion of the housing, a head portion for turning of said knob, and an axially inner end face operative to bear against an axially outer end face of said plug axially to drive said plug into the housing for sealing thereof upon turning of said knob when in threaded engagement with the housing; and fastener means for rotatably coupling said knob to said plug, said fastener means including a shank extending axially through a larger diameter central axial bore in said knob and secured at the inner end thereof to said plug, a head having a diameter greater than that of said central bore to provide an axially inner end face operative to engage an axially outer end face of said knob, and spacer means for positively fixing the axial spacing between said inner end face of said head of said fastener means and outer end face of said plug to a distance greater than the axial spacing between said inner end face and outer end face of said knob for free turning movement of said knob relative to said plug. 9. A combination as set forth in claim 8, wherein the inner end of said shank of said fastener means is threaded into a correspondingly threaded bore in said plug to secure the same, and said spacer means includes a larger diameter axial section of said shank forming at its intersection with the threaded inner end of said shank a shoulder operative to engage the outer end face of said plug to fix positively the axial spacing between the head of said fastener means and said plug upon securing of said fastener means to said plug. 10. A combination as set forth in claim 9, wherein said axial section of said shank of said fastener means is cylindrical and serves as a spindle on which said knob rotates at the central bore thereof. 11. A combination as set forth in claim 10, wherein said axial section extends between said inner end of said shank and said head of said fastener means and defines at its intersection with the latter said axially inner end face of said head. 12. A combination as set forth in claim 8, wherein said threaded portion of said knob is in the form of an annular skirt extending coaxially inwardly from said head portion of said knob to define a socket for receiving an axially outer portion of said plug. 13. A combination as set forth in claim 12, wherein said skirt is threaded at its outer diameter for threaded engagement with a correspondingly threaded outer portion of the housing bore. 14. A combination as set forth in claim 13, wherein there is radial clearance between said skirt and outer portion of said plug to accommodate misalignment between said knob and plug when respectively secured and sealed in the housing bore. 15. A combination as set forth in claim 8, wherein said central bore in said knob is counterbored at its axially outer end to receive therein the head of said fastener means. 16. A combination as set forth in claim 15, further comprising cap means received in the outer end of the counterbore in said knob to close the same. 17. A combination as set forth in claim 8, wherein said sealing element is axially retained in an annular recessed groove concentric with the housing bore, and said plug has a cylindrical portion movable into the sealing element to compress the sealing element radially between said plug and housing. 18. A combination as set forth in claim 17, wherein said plug and the housing bore have diametrically stepped portions cooperative positively to limit the extent of axial insertion of said plug into the housing bore. 19. A combination as set forth in claim 8, further comprising a filter chamber coaxial with said housing bore, said plug assembly including a cylindrical filter, and means securing said filter to said plug. 20. A combination as set forth in claim 19, wherein said means securing includes a spring extending axially within said filter and secured at one end to said plug and at its other end to an inner end cap holding said filter axially trapped between such inner end cap and plug. 21. In a housing having a bore, a plug assembly for sealingly closing the housing bore comprising: a plug adapted to be sealed by an annular sealing element to the inner diameter of the housing bore; a knob for axially driving said plug in the housing bore, said knob having an axially extending threaded portion for threaded engagement with a correspondingly threaded axial portion of the housing, and a head portion for turning of said knob to effect such threaded engagement and axial driving of said plug; and fastener means for rotatably coupling said knob to said plug, said fastener means including a shank extending through a larger diameter central axial bore in said knob and secured at a distal end thereof to said plug, a head having a diameter greater than said central bore to provide an axially inner face cooperative with an axially outer face of said knob to trap axially therebetween a portion of said knob, and spacer means for positively fixing the axial spacing between said inner and outer faces to a distance greater than the axial length of said trapped portion of said knob.