초록 ▼

A liquid dispensing module includes a dispenser body assembly, a flexible seal, a needle, and an actuator. The dispenser body assembly includes a liquid inlet, a discharge outlet, and a flow channel including a valve seat between the inlet and outlet. The flexible seal engages the dispenser body ass

A liquid dispensing module includes a dispenser body assembly, a flexible seal, a needle, and an actuator. The dispenser body assembly includes a liquid inlet, a discharge outlet, and a flow channel including a valve seat between the inlet and outlet. The flexible seal engages the dispenser body assembly and includes a downstream end. The needle includes an enlarged portion engaging and retaining the downstream end of the flexible seal to place the flexible seal in lengthwise compression between the enlarged portion and the dispenser body assembly. The needle also includes a valve element that moves between open and closed positions. The flexible seal prevents liquid from leaking out of the flow channel.

대표청구항 ▼

1. A liquid dispensing module for dispensing a viscous liquid comprising: a dispenser body assembly including a liquid inlet, a discharge outlet, and a flow channel capable of directing a flow of the liquid from said liquid inlet to said discharge outlet, said flow channel including a valve seat bet

1. A liquid dispensing module for dispensing a viscous liquid comprising: a dispenser body assembly including a liquid inlet, a discharge outlet, and a flow channel capable of directing a flow of the liquid from said liquid inlet to said discharge outlet, said flow channel including a valve seat between said liquid inlet and said discharge outlet;an actuator including an actuator chamber adapted to be in communication with a pressurized air source;a flexible seal including an upstream end sealingly engaging said dispenser body assembly and including a downstream end, said flexible seal adapted to seal said flow channel from said actuator; anda needle including a valve element and operable by said actuator for reciprocating movement in said dispenser body assembly between an open position in which said valve element is disengaged with said valve seat allowing liquid flow from said discharge outlet and a closed position in which said valve element is engaged with said valve seat preventing liquid flow from said discharge outlet, said needle including an enlarged portion engaging and retaining said downstream end of said flexible seal to allow reciprocating movement of said downstream end with said needle and to place said flexible seal in lengthwise compression between said upstream and downstream ends,wherein said flexible seal further includes a central portion between said upstream and downstream ends and extending radially outwardly from said needle to form an interior cavity between said central portion and said needle, and said interior cavity is in fluid communication with said actuator chamber to allow air pressurization of said interior cavity for preventing said central portion from collapsing onto said needle. 2. The liquid dispensing module of claim 1, wherein said dispenser body assembly includes a recess with a transverse surface, said upstream end engaged and retained by said transverse surface to place said flexible seal in lengthwise compression between said transverse surface and said enlarged portion. 3. The liquid dispensing module of claim 1, further comprising: an annular groove formed at least partially by said enlarged portion to receive said downstream end of said flexible seal and place said flexible seal in lengthwise compression. 4. The liquid dispensing module of claim 3, wherein said annular groove further comprises a converging portion, and said downstream end of said flexible seal is adapted to be wedged into said converging portion to seal said flow channel and to further provide lengthwise compression in said flexible seal. 5. The liquid dispensing module of claim 1, wherein said dispenser body assembly further comprises an adjustably positioned needle guide adapted to preload said flexible seal with the lengthwise compression. 6. The liquid dispensing module of claim 1, wherein said flexible seal has a durometer of about 65. 7. The liquid dispensing module of claim 1, wherein said flexible seal has a durometer in the range of 40-90. 8. A liquid dispensing module for dispensing a viscous liquid comprising: a dispenser body assembly including a liquid inlet, a discharge outlet, and a flow channel capable of directing a flow of the liquid from said liquid inlet to said discharge outlet, said flow channel including a valve seat between said liquid inlet and said discharge outlet, said dispenser body assembly further including a recess with a transverse surface;an actuator including an actuator chamber adapted to be in communication with a pressurized air source;a needle including a valve element, said needle operable by said actuator for reciprocating movement in said dispenser body assembly between an open position in which said valve element is disengaged with said valve seat allowing liquid flow from said discharge outlet and a closed position in which said valve element is engaged with said valve seat preventing liquid flow from said discharge outlet; anda flexible seal including a downstream end sealingly engaging said needle and an upstream end engaged and retained by said transverse surface to place said flexible seal in lengthwise compression between said upstream and downstream ends, said flexible seal adapted to seal said flow channel from said actuator,wherein said flexible seal further includes a central portion extending radially outwardly from said needle to form an interior cavity between said central portion and said needle, and said interior cavity is in fluid communication with said actuator chamber to allow air pressurization of said interior cavity for preventing said central portion from collapsing onto said needle. 9. The liquid dispensing module of claim 8, wherein said recess further comprises a converging portion, and said upstream end of said flexible seal is adapted to be wedged into said converging portion to seal said flow channel and to further provide lengthwise compression in said flexible seal. 10. The liquid dispensing module of claim 8, wherein said dispenser body assembly further comprises an adjustably positioned needle guide adapted to preload said flexible seal with lengthwise compression and further wedge said upstream end of said flexible seal into engagement with said transverse surface of said recess. 11. The liquid dispensing module of claim 8, wherein said flexible seal has a durometer of about 65. 12. The liquid dispensing module of claim 1, wherein said enlarged portion of said needle is spaced in an upstream direction from said valve seat in said flow channel such that said downstream end of said flexible seal remains spaced from said valve seat during the reciprocating movement of said needle. 13. The liquid dispensing module of claim 8, wherein said downstream end of said flexible seal is located so as to remain spaced from said valve seat of said dispenser body assembly during the reciprocating movement of said needle. 14. An assembly for use in a liquid dispensing module for dispensing a viscous liquid, the assembly comprising: a dispenser body assembly component with an annular recess defining a transverse first surface;a needle adapted for reciprocating movement in the dispenser body assembly and including a valve element, said valve element movable between an open position and a closed position; anda flexible seal including a downstream end sealingly engaging said needle and including an upstream end engaged and retained by said transverse surface to place said flexible seal in lengthwise compression between said upstream and downstream ends; andwherein said annular recess includes first and second sides spaced from one another and configured to engage said upstream end of said flexible seal, each of said first and second sides connected to said transverse first surface, which is oriented transverse to a direction of needle reciprocating movement and engages said upstream end of said flexible seal to apply the lengthwise compression to said flexible seal, said annular recess further including a converging portion defined by said first and second sides converging toward each other as the first and second sides approach said transverse first surface, and said upstream end of said flexible seal is wedged into said converging portion. 15. The assembly of claim 14, wherein said dispenser body assembly component further comprises a needle guide having a passageway, said needle being mounted for reciprocating movement in said passageway. 16. The assembly of claim 15, wherein said needle guide is adjustably positioned with respect to said needle to preload said flexible seal with lengthwise compression. 17. The assembly of claim 14, wherein said flexible seal has a durometer of about 65. 18. The assembly of claim 14, wherein said flexible seal has a durometer in the range of 40-90. 19. The assembly of claim 14, wherein said flexible seal includes an inner sidewall and an outer sidewall, said downstream end terminates in a tip having a transverse end surface extending from said inner sidewall to said outer sidewall of said flexible seal said needle further includes an enlarged portion engaging and retaining said downstream end of said flexible seal, such that said downstream end is adapted to reciprocate with said needle; and the assembly further comprises: an annular groove formed at least partially by said enlarged portion to receive said downstream end of said flexible seal, said annular groove including a second surface oriented transverse to a direction of needle reciprocating movement and engaging said transverse end surface of said tip such that said transverse end surface and a portion of said outer sidewall of said tip remain contained within said annular groove while said transverse first and second surfaces apply lengthwise compression to said flexible seal. 20. The assembly of claim 19, wherein said annular groove further comprises a converging portion, and said downstream end of said flexible seal is wedged into said converging portion. 21. The assembly of claim 19, wherein said annular groove includes first and second sides spaced from one another and configured to engage said downstream end of said flexible seal, each of said first and second sides connected to said second surface that is oriented transverse to a direction of needle reciprocating movement.