KR20140113442A - Liquid dispensing syringe - Google Patents

Abstract

The present invention relates to a syringe for dispensing liquid material to a substrate. In one embodiment, the syringe includes a barrel having a first end, a second end, and an internal reservoir. The piston is slidably disposed within the reservoir and is movable to increase or decrease the volume of the internal reservoir near the first end of the barrel. At least a portion of at least one of the barrel, the piston or the dispensing tip comprises a material selected to maintain operational structural integrity of the dispensing syringe at elevated temperatures.

Description

[0001] LIQUID DISPENSING SYRINGE [0002]

The present application claims benefit of the filing of U.S. Provisional Patent Application Serial No. 61 / 794,551, filed March 15, 2013, which is hereby incorporated by reference in its entirety.

The present invention relates generally to the field of dispensing liquid materials, and more particularly to a syringe for dispensing liquid material.

Various types of dispensers are used in many industries to place liquids, such as adhesives, adaptive coating materials, solder paste, solder fluxes, and other similar materials, onto a substrate during the assembly process. One type of liquid distributor is a syringe type dispenser having a dispenser body forming a barrel reservoir to hold a supply of liquid material to be dispensed. A dispensing tip is associated with the syringe at one end and is in fluid communication with the reservoir. The piston disposed in the reservoir can move inside to pressurize the liquid in the reservoir and thereby dispense a small amount of liquid onto the substrate from the dispensing tip.

Many industrial applications require liquids to be dispensed at precise locations with very accurate volumes. To this end, the liquid distributor comprises an actuator for moving the piston in the reservoir in a controllable and predictable manner. By way of example, pneumatic actuators are well known in the art and use compressed air that is adapted to dispense liquid from a dispenser by moving the piston. Other types of actuators, such as linear actuators, may be used by those skilled in the art to control the movement of the pistons in the reservoir. In other applications where exact dispensing is not required, the piston can be moved through a manual process.

In some applications, the liquid to be dispensed must be heated to at least about < RTI ID = 0.0 > 150 C. < / RTI > As an example, dispensing hot melt type adhesives, such as polyurethane glue (PUR), typically involves heating the adhesive to about 150 ° C or higher and holding it at that temperature until the adhesive is dispensed to the desired substrate in need. When the dispensers of the syringe type used to dispense such liquids contain polymeric materials, the elevated temperature can affect the uniformity or performance of the syringe component and limit the effectiveness of the dispenser. There is a need for a syringe type dispenser that can overcome these and other drawbacks of conventional syringe type dispensers.

According to one form, the dispensing syringe comprises a first end and a second end and an internal reservoir. A piston is slidably disposed within the internal reservoir and is movable between first and second positions within the reservoir to increase or decrease the volume at a first end of the barrel. The dispensing syringe further comprises a dispensing tip proximal to the first end of the barrel. The dispensing tip includes an outlet in fluid communication with the reservoir for dispensing liquid material to the substrate. At least a portion of at least one of the barrel, the piston or the dispensing tip comprises a material selected to maintain the operational structural integrity of the dispensing syringe at a temperature of greater than about 150 ° C.

The piston may have a generally hemispherical surface profile having a first end and a second end and having elongated apexes extending along the central axis of the piston. The surface profile facilitates fluid distribution from the first end of the barrel when the piston moves in a direction toward the first end. The dispense syringe reduces or eliminates air trapping and minimizes the volume of material left in the syringe after the piston is fully engaged with the first end of the barrel.

The piston may include a circumferentially extending wiper seal positioned between the first and second ends of the piston. The piston may further include one or more fluid passages formed on the hemispherical surface. The fluid passageway extends between the first and second ends of the piston and assists in reducing air accumulation beneath the first wiper when the internal reservoir is filled from the first end of the barrel. The piston is configured to allow gas to pass from the first volume while retaining the liquid in the first volume. In one embodiment, at least a portion of the piston is configured to facilitate passage of gas from the first volume while retaining the liquid.

The syringe barrel may include a radially inwardly extending ledge within the internal reservoir. The ledge engages the wiper seal when the piston moves toward the first end of the barrel to engage the piston with the first end. The engagement between the wiper seal and the ledge squeezes the liquid material from under the wiper to minimize liquid material remaining in the reservoir as the piston moves to the first end of the barrel.

The adapter is used to couple the dispensing syringe to the source of compressed air. The adapter may include a first end for engagement with the syringe barrel and a second end for engagement with the source of compressed air. The first and second hubs on the first end of the adapter engage the ear of the barrel to secure the adapter to the barrel. The barrel ears have a small radial dimension compared to the circumferential length of the ears so that deflection of the ears is reduced or eliminated during use of the dispensing syringe. The adapter may further include a seal extending from the first end of the adapter for engaging the open end of the barrel when the first and second hubs engage the barrels.

The end cap may be used with a syringe barrel when the adapter is used to couple the syringe barrel to the source of compressed air.

The tip cap may be secured to the male luer connector at the first end of the syringe barrel. The tip cap may include an end wall having a skirt and an annular boot extending axially outwardly from the end wall. The boot is disposed concentrically within the skirt to form a space for frictionally gripping the male luer connector therein.

In another aspect, at least a portion of at least one of the components of the syringe may comprise a material selected to maintain structural integrity of the syringe at an elevated temperature. By way of example, one or more of the syringe barrel, piston or luer coupling may include a material capable of maintaining the structural integrity of the syringe at elevated temperatures. In addition, one or more tip caps, end caps, or adapters for coupling the syringe barrel to the source of compressed air may include a material capable of maintaining structural integrity of the syringe at elevated temperatures.

These and other aspects, objects and advantages will become more apparent to those skilled in the art when reviewing the following detailed description, which is to be read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and, together with the general description given above and the detailed description below, serve to explain the principles of the invention.

1 is a perspective view of an exemplary dispensing syringe;
Figure 2 is an exploded perspective view of the dispensing syringe of Figure 1;
3 is a side elevational view of the barrel of the dispensing syringe of FIG.
Figure 3a is an enlarged cross-sectional view of the syringe barrel of Figure 3 taken along line 3A-3A.
Figure 3b is an enlarged cross-sectional view of an alternative embodiment of the syringe barrel of Figure 3;
Figure 4 is a perspective view of an exemplary end cap for use with the syringe barrel of Figure 3;
4A is a cross-sectional view of the end cap of FIG. 4 taken along line 4A-4A;
Figure 5 is a perspective view of an exemplary tip cap for use with the syringe barrel of Figure 3;
Figure 5a is a cross-sectional view of the tip cap of Figure 5 on the syringe barrel of Figure 3;
Figure 6 is a side elevation view of the exemplary adapter shown in Figures 1 and 2 for use with the syringe barrel of Figure 3;
6A is a cross-sectional view of the adapter of FIG. 6 taken along line 6A-6A;
7 is a cross-sectional view illustrating a piston of the syringe of FIG. 1 at a first end of a syringe barrel;

Figures 1, 2, 3, 3a, and 3b illustrate an exemplary liquid dispensing syringe 10. The syringe 10 includes a conventional elongated syringe barrel 12 having a first end 14 for dispensing liquid material and a second end 16 opposite the first end 14. The barrel 12 forms an internal reservoir 18 (FIG. 3) for receiving liquid material to be dispensed from the first end 14. The piston 20 is slidably disposed within the interior reservoir 18 and slidably moves between the first end 14 and the second end 16 to move the piston 20 in the direction toward the first end 14 To dispense the liquid material from the first end (14). The dispensing tip 22 is removably coupled to the first end 14 of the barrel 12 for communicating with the internal reservoir 18 so that liquid material can be dispensed from the outlet 24 of the dispensing tip 22 .

The first end 14 of the barrel 12 includes a male luer connector 26 adapted to receive a corresponding female luer 28 provided in the dispensing tip 22, 22 may be coupled to the first end 14 of the barrel 12, as shown in Figures 3, 3a, and 3b. The male Luer connector 26 includes a collar 30 having male coupling tips 29 and female threads 31 for securing the dispensing tip 22. The second end 16 of the barrel 12 includes a relatively large diameter opening 70 and extends from the second end 16 of the barrel 12 to the actuator such as a source of compressed air 36 Radially outwardly extending flanges or ears 74,76 for securing the adapter 80 or the end cap 110 to facilitate engagement of the end cap 110. [

An example of one piston 20 is shown in Figures 2 and 7, and an exemplary piston 20 is shown, although many different pistons may be used. The piston 20 includes a first end 32 configured to pressurize the liquid material through the first end 14 of the barrel 12 and into the dispensing tip 22. The first end 32 of the piston 20 mates with the first end 14 of the barrel 12 to force liquid material into the dispensing tip 22. The second opposing end 34 of the piston 20 is exposed to the actuator as in the source 36 of compressed air (Figure 1) so that the piston 20 extends from the second end 16 of the barrel 12 And may act in a direction toward the first end 14 of the barrel 12. [ At least one first circumferential wiper 40 extends radially outwardly from the hemispherical surface 38 of the piston 20 to sealingly engage the inner wall of the barrel 12. The wiper 40 may be in the form of a skirt or flange extending circumferentially about the body of the piston 20 and forming a step 41 with respect to the hemispherical surface 38. It is believed that the stepped portion 41 is important to provide a minimum dead space volume in the internal reservoir 18. A second wiper 42 may be provided adjacent the second end 34 of the piston 20 and is generally formed identically to the first wiper 40 to sealably engage the inner surface of the barrel 12. [ do.

The surface of the piston 20, which is proximal to at least the first and second wipers 40 and 42 and optionally in the region 43 between the first and second wipers 40 and 42, Venting of gaseous materials, such as air, that can be trapped within the internal reservoir 18 while preventing escape of the reservoir 18. The micro- By way of example, the first wiper 40, the second wiper 42, and / or the region 43 may be configured such that the gaseous material passes from the internal reservoir 18, but the liquid material is retained within the internal reservoir 18 Lt; / RTI > Alternatively, some or all of the piston 20 may be formed of a material that is gas permeable, but liquid impermeable, to facilitate passage of gaseous material from the internal reservoir 18. It will be appreciated that a variety of other methods may be used to facilitate the passage of gaseous material from the internal reservoir 18, while preventing liquid material from escaping. The region 43 may also have a concave profile to minimize material shear and pressure and to minimize gas capture between the first and second wipers 42,43.

2 and 7, the first end 32 of the piston 20 moves the piston 20 toward the first end 14 of the barrel 12 to dispense the liquid material from the tip 22 Has a smooth radial profile that forms a generally hemispherical surface 38 that more evenly distributes the pressure across the liquid material, since it minimizes shear in the liquid material. In the illustrated embodiment, the apex portion 44 of the piston 20 forms a tip at the first end 32 of the piston 20. The apex portion 44 is configured such that the apex portion 44 extends outwardly from the hemispherical surface 38 thereby defining the male luer 26 when the piston 20 engages the second end 14 of the barrel 12. [ May be elongate along the central axis 45 of the piston 20 to extend downward into a portion of the piston 20. The elongated apex portion 44 includes a curved region 44a that provides a smooth transition from the hemispherical surface 38 and forms, for example, a bullet-nose shape. The elongated apex portion 44 of the piston 20 assists in dispensing liquid material through the dispensing tip 22 and minimizes the waste retained in the dispenser 10.

The piston 20 may further include a flow passage 46 formed on the hemispherical surface 38 of the piston 20 between the apex portion 44 and the first wiper 40. The flow passage 46 may be defined by channels formed in the outer surface 38 of the piston 20 or may be defined by outwardly extending ribs or surfaces disposed on the first end 32 of the piston 20, Omitted). In the illustrated embodiment, the flow passages 46 are channels formed into the first end 32 of the piston 20 and are approximately 0.003 to 0.005 inches deep.

When the barrel reservoir 18 is filled from the first end 14 of the barrel 12 the liquid material flows from the apex 44 of the piston 20 toward the first wiper 40 through the flow passage 46 . The movement of the liquid material along the flow passage 46 forces the air entrained toward the first wiper 40 through which air can pass. The wiper 40, however, prevents liquid material from passing therethrough. In this process, air accumulation under the first wiper 40 is reduced or eliminated.

In the embodiment shown in Figures 3A-B, the first end 14 of the syringe barrel 12 and the dispensing tip 22 are shown in more detail. The barrel 12 cooperates with the design of the dispensing tip 22 to minimize sheath of liquid material and to eliminate the formation of air pockets within the barrel reservoir 18 during filling and / or dispensing operations. The first end 14 of the barrel 12 includes a smooth curved profile 48 corresponding to the hemispherical surface 38 of the first end 32 of the piston 20 for this purpose. In one embodiment, the curved profile 48 may include a radius in the range of about 5/32 inch to about 3/16 inch or larger. The curved profile 48 helps to guide the liquid material through the outlet orifice 52 and outlet passage 50 of the first end 14 of the barrel 12 to the inlet 54 of the dispensing tip 22, Provides a smooth transition in. The inner diameter of the outlet passage 50 may be tapered to minimize shear in the liquid material as the liquid material is dispensed from the barrel 12 into the dispensing tip 22. In the embodiment shown in FIG. 3A, the outlet orifice 52 of the syringe barrel 12 has a relatively blunt shape. Alternatively, the outlet orifice 52a of the barrel 12 may progressively widen outwardly toward the interior of the dispensing tip inlet 54 to form a first end 14 of the barrel 12 and a second end 14b of the barrel 12, Providing a smooth transition between the tips 22. The interior of the dispensing tip inlet 54 is sized generally to minimize air entrapment within the dispensing tip 22 and to provide a generally smooth transition between the inlet 54 and outlet passage 56 of the dispensing tip 22, Frusto-conical sidewalls or bullet-projected sidewalls.

3A, the outlet passage 50 of the syringe barrel 12 extends over a circumferential groove 60 formed in the inlet 54 of the dispensing tip 22. This groove 60 or "stripper ring" is formed in the dispensing tip 22 during the molding process and is configured such that when one half of the core is removed from the casted tip 22, Assists in holding on the other half of the member. The tip 22 is subsequently retracted from the core member and the stripper ring 60 remains in the inlet passage of the dispensing tip 22.

The first end 14 of the syringe barrel 12 is adapted to engage the first wiper 40 on the piston 20 when the piston 20 engages the inner surface of the first end 14 of the barrel 12. [ And further includes an applied internal ledge (62). The inner ledge 62 engages the first wiper 40 and the liquid material beneath the wiper 40 is further pressurized from the wiper 40 thereby reducing liquid material waste. The inner ledge 62 creates a corresponding radially outwardly extending ledge 64 on the outer surface of the barrel 12 so that the first end 14 of the syringe barrel 12 is visually The barrel 12 has a uniform wall thickness to provide an appearance.

2 and 3, the second end 16 of the syringe barrel 12 includes a relatively large-diameter opening 70 and has a radially outwardly extending flange 72. As shown in FIG. A pair of opposed taps or ears 74,76 facilitate the fastening of the adapter 80 or end cap 110 for coupling the syringe 10 to the actuator as will be described in more detail below. Radially outward from the flange 72 in the opposite direction. The radially extending length of the ears 74, 76 is generally smaller than conventional syringe barbs in order to minimize warping of the ears 74, 76 during use. This deflection causes a change in the dispensing volume of the liquid material when a pressure change is applied to the syringe 10 to cause the piston 20 to move in the direction toward the first end 14 of the barrel 12. [ The repeated warping of the sleeves 74, 76 over time causes the material of the barrel 12 to become tired, thereby further increasing the deflection of the strands 74, 76 and reducing the change in the dispensing volume of the liquid material . Advantageously, a reduction in the length of the ears 74, 76 in the syringe 10 of the illustrated embodiment reduces the warpage of the ears 74, 76, thereby reducing the volume of liquid material dispensed from the syringe 10 Improve island consistently. In the illustrated embodiment, each ear 74, 76 includes an adapter 80 or end cap (not shown) that can be coupled to the second end 16 of the barrel 12, Radially outwardly extending detents or bumps 78 formed on the outer perimeter thereof to provide positive engagement with the radially outwardly extending bosses 110. As shown in FIG.

6 and 6A illustrate an exemplary adapter (not shown) configured to couple to the second end 16 of the syringe barrel 12 to facilitate coupling of the syringe 10 to the actuator, such as the source of compressed air 36 80). The adapter 80 is coupled to a conduit (not shown) in communication with a source of compressed air 36 and a first end 82 adapted to be coupled to the second end 16 of the barrel 12. In the illustrated embodiment, And a second end portion 84 adapted to be received. The second end 84 of the adapter may include a barb 86 that facilitates securing the conduit. The first end 82 of the adapter 80 is coupled to the first and second ear 74 and 76 at the second end 16 of the barrel 12 in a bayonet- And first and second hubs 88 and 90 disposed opposite to each other. Each hub 88, 90 is defined by a radially extending rim 92, an end wall 94 spaced from the rim 92, and a circumferentially extending sidewall 96 extending therebetween. The end wall 94 extends toward the second end 16 of the barrel 12 when the adapter 80 is twisted to receive the ears 74 and 76 within each hub 88 and 90 of the adapter And has an inner surface 98 (FIG. 6A) that is inclined in a direction toward the rim 92 to closely pull the adapter 80.

6 and 6A, and in FIG. 2, the first end 82 of the adapter 80 is a centrally positioned, tubular, cylindrical portion that projects from the end wall 94 in a direction opposite to the second end 84. [ Further comprising a seal (100) disposed on a boss (102). The radially outwardly extending flange 104 retains the seal 100 on the cylindrical boss 102. In the illustrated embodiment, the seal 100 is an O-ring, but it should be understood that many different types of sealing devices could alternatively be used. The seal extends axially into the second end 16 of the syringe barrel 12 and engages the inner surface of the syringe barrel 12. As shown in FIG. The adapter 80 is configured to receive the syringes 74 and 76 of the syringe barrel 12 within the hubs 88 and 90 of the adapter 80 to fully engage the seal 100 with the inner surface of the syringe barrel 12. [ Must be rotated to accommodate. The inclined surface 98 of the end wall 94 defines the seal 100 at the second end of the barrel 12 when the ears 74,76 are received within the hubs 88,90 of the adapter 80 16 and the seal 100 sealingly engages the inner surface of the syringe barrel 12.

The air can escape through the interior of the reservoir 18 past the seal 100 prior to twisting the adapter 80 to receive the posts 74 and 76 in the hubs 88 and 90 of the adapter 80 have. The pawls 78 formed on the ears 74 and 76 are positioned on the ears of the barrel 12 when the ears 74 and 76 are fully disposed within the hubs 88 and 90 of the adapter 80 (Fig. 6A) formed in the side walls 96 of the adapter 80 to provide snap fit of the adapter 80 to the adapter 80 (Figs. And actively indicates that it is fully locked onto the second end 16 of the barrel 12. In the illustrated embodiment, the slots 79 are formed by openings 79a formed through the end walls 94 and extending into the side walls 96.

The seal 100 is formed on the second end 16 of the syringe barrel and engages a chamfer 106 (FIG. 3) adjacent the opening 70. The position of the chamfer 106 in the opening 70 is such that the seal 100 does not extend too far into the syringe barrel 12 and thereby the adapter 80 is properly seated and locked onto the syringe barrel 12. [ ≪ / RTI > The adapter 80 facilitates sliding of the second end 16 of the syringe barrel 12 due to the shallow engagement of the seal 100 and the chamfer 106 when the adapter 80 is not properly seated and locked .

Figures 4 and 4a illustrate an end cap 110 that may be secured to the second end 16 of the syringe barrel 12 instead of the adapter 80. [ The end cap 110 includes an annular edge 112 and oppositely disposed first and second flanges 114, 116 extending generally radially outwardly from the edge 112. The oppositely disposed first and second engagement tabs 118 and 120 similar to the hubs 88 and 90 of the adapter 80 are configured to engage the edges 112 of the barrel 12, And extends from the bottom side. Each engagement tab 118,120 includes a side wall 122 extending at right angles to the edge 112 and an end wall 124 extending parallel to the edge 112. As shown in FIG. The end wall 124, the edge 112 and the end wall 122 are adapted to receive the first and second ear 74 and 76 provided on the second end 16 of the syringe barrel 12 Generally forming circumferentially extending slots.

The end cap 110 further includes a conventional cap core 130 formed by the first and second concentric sidewalls 132 and 134 and the end wall 136. The first side wall 132 is coupled to the second side wall 134 by an arcuate end portion 138 that extends axially from the edge 112 and extends therebetween. An end wall 136 is provided on the second end of the second side wall 134 and closes the cap. The central portion 130 of the end cap 110 causes the edge 112 to bend and thereby facilitate closure of the second end 14 of the syringe barrel 12 by the end cap 110. A generally circumferential extension sealing bead 140 is disposed on the first sidewall 132 of the central portion 130 to provide a sealing engagement of the inner surface of the syringe barrel 12 and the end cap 110. [ The elongated stem 142 is centered on the end wall 136 and extends downwardly from the end wall 136. The stem 142 facilitates the formation of the end wall 136 during manufacture. The first tab 118 is engaged with the first ear 74 at the second end 14 of the barrel 12 in order to seal the second end 14 of the barrel 12 by the end cap 110. [ And the second tab 120 is pivoted downwardly to snap against the second ear 76 while pressing the center portion 130 to allow the second tab 120 to be flexibly extended with respect to the second ear 76, do.

Figures 5 and 5A illustrate an exemplary tip cap 150 that may be used with the syringe 10. The tip cap 150 is configured to fit over the male luer 26 at the first end 14 of the syringe barrel 12. In the illustrated embodiment, the tip cap 150 generally includes a circular end wall 152, although the end wall 152 may have many different shapes. The end wall 152 is flute disposed around the outer periphery thereof to facilitate gripping of the tip cap 150 during installation or removal of the tip cap 150 from the syringe barrel 12, a lobe or other shape. A generally cylindrical skirt 154 extends from the end wall 152 and is sized to be received against the collar 30 of the male luer 26. A conventional cylindrical boot 156 is also positioned concentrically within the skirt 154 so as to extend from the end wall 152 and to be received between the collar 30 of the male luer 26 and the male coupling tip 29. The skirt 154 and the boot 156 are sized and dimensioned to provide friction fit to the male luer 26 so that the tip cap 150 is retained on the first end 14 of the syringe barrel 12. [ do. Centered bead 160 disposed on the interior of the end wall 152 is located on the syringe barrel 12 and is positioned within the syringe barrel 12. As the tip cap 150 is securely seated on the male luer 26 of the syringe barrel 12, And sealingly engages the outlet orifice 52 at the first end 14.

Tip cap 150 further includes one or more circumferentially extending ribs or ridges 158 that are sized to engage threads of male luer 26 and provided on boot 156. The rib 158 is configured such that the tip cap 150 can be axially urged onto the first end 14 of the syringe barrel 12 such that the boot 156 is deformed radially inwardly, (158) is mounted on the threaded portion (31) on the male luer (26). The tip cap 150 is positioned on the first end 14 of the syringe barrel 12 by twisting the tip cap 150 to advance the tip cap 150 over the threaded portion of the male luer 26. [ can do. The tip cap 150 may be removed from the first end 14 of the syringe barrel 12 by spacing the tip cap 150.

In accordance with another aspect of the principles of the present invention, at least some of the one or more components of the dispensing syringe includes a material selected to maintain structural integrity of the dispensing syringe at elevated temperatures so that the dispensing syringe operates as intended at such elevated temperature. Thus, dispense syringes can be used to dispense liquid materials, such as hot melt adhesives, that require heating at elevated temperatures. By way of non-limiting example, a dispense syringe according to the principles of the present invention may be used to dispense a polyurethane hot melt adhesive (PUR) at elevated temperatures up to about 150 < 0 > C. In another embodiment, the material may be selected to maintain structural integrity at elevated temperatures up to about < RTI ID = 0.0 > 200 C. < / RTI > In another embodiment, the material may be selected to maintain structural integrity at elevated temperatures above about 200 < 0 > C. Because one or more components of the dispensing syringe, such as a barrel, piston, or luer coupling, are formed of a material that maintains structural integrity at elevated temperatures, these components are not softened to the temperature at which the structural integrity of the syringe is conferred, Any problems such as leakage or explosion in a pressure state can be avoided.

In one embodiment, one or more components of the dispensing syringe 10 may include a resin that is resistant to elevated temperatures. One or more components, such as barrel 12, piston 20, dispense tip 22, or luer connector 26, may be connected to component 10 at an elevated temperature such that the intended operation of dispensing syringe 10 is not adversely affected. Polybutylene terephthalate (PBT) or any other suitable material to maintain the structural integrity of the substrate. It will also be appreciated that any other components of dispensing syringe 10 such as tip cap 150, adapter 80, end cap 110 or any other component of dispensing syringe or any other component of dispensing syringe, The component may comprise polybutylene terephthalate (PBT) or any other suitable material to maintain the structural integrity of the components at elevated temperatures. The material may further include additives to improve the properties or performance of the material during use. By way of example, the material may be a composite material comprising reinforcing fibers such as, but not limited to, glass fibers to improve the strength of the material. Although materials containing reinforcing fibers are described herein, it should be understood that composite materials formed from other reinforcing materials can be used as an alternative.

In another form, one or more components of the dispensing syringe 10 may include a material comprising an additive to improve the durability of the material to flame or ultraviolet (UV) when desired. Various other components of dispensing syringe 10, such as adapter 80, end cap 110, or tip cap 150, also include materials that retain structural integrity at elevated temperatures, including the additives described above So that the intended operation of the dispensing syringe 10 is not adversely affected.

While the invention has been described by description of several illustrative embodiments and while the embodiments have been described in considerable detail, the scope of the appended claims is not intended to be limited or limited to such details. The various forms described herein may be used alone or in combination. Additional advantages and modifications will be apparent to those skilled in the art. Accordingly, the invention in its broader aspects is not limited to the specific details, representative apparatus, and methods and examples shown and described. It is therefore to be understood that such detail is within the scope of the general inventive concept.

Claims (20)

A barrel having a first end and a second end and defining an internal reservoir; And
A dispensing tip proximate said first end of said barrel, said dispensing tip comprising an outlet in fluid communication with said reservoir,
Wherein at least a portion of at least one of the barrel or the dispensing tip comprises a material selected to maintain the operational structural integrity of the dispensing syringe at a temperature greater than about 150 < 0 > C. The method according to claim 1,
Said material comprising a high temperature resin. 3. The method of claim 2,
Wherein said material comprises polybutylene terephthalate. 3. The method of claim 2,
Wherein said material is a composite material further comprising a fibrous reinforcement. The method according to claim 1,
Further comprising an adapter selectively removably coupled to the second end of the barrel to couple the barrel to a source of pressurized fluid. The method according to claim 1,
Further comprising a piston slidably disposed within the internal reservoir. The method according to claim 6,
Wherein the piston comprises polybutylene terephthalate. The method according to claim 6,
Further comprising a hot melt adhesive disposed within the internal reservoir. A barrel having a first end and a second end and defining an internal reservoir;
A piston slidably disposed within the reservoir and thereby increasing or decreasing the volume of the internal reservoir proximal to the first end of the barrel, the piston having a first end and a second end, The first end having a generally hemispherical surface profile having a elongated apex extending along a central axis for dispensing fluid from the first end of the barrel as it moves toward the first end of the barrel The piston; And
A luer coupling at said first end of said barrel adapted to receive a dispensing tip;
The luer coupling including an outlet orifice and an outlet passage in fluid communication between the outlet orifice and the reservoir;
The exit passage tapering along the axial length;
Wherein at least a portion of at least one of the barrel, the piston or the luer coupling comprises a material selected to maintain the operational structural integrity of the dispensing syringe at a temperature of greater than about 150 < 0 > C. 10. The method of claim 9,
Said material comprising a high temperature resin. 11. The method of claim 10,
Wherein said material comprises polybutylene terephthalate. 11. The method of claim 10,
Wherein said material is a composite material further comprising a fibrous reinforcement. 10. The method of claim 9,
Further comprising an adapter selectively removably coupled to the second end of the barrel to couple the barrel to a source of pressurized fluid. 10. The method of claim 9,
Further comprising an end cap selectively removably coupled to the second end of the barrel to seal the barrel. 10. The method of claim 9,
A tip cap selectively removably coupled to the luer coupling at the first end of the barrel such that when the tip cap is securely seated on the luer coupling, Further comprising the tip cap sealingly coupling the outlet orifice. 10. The method of claim 9,
The barrel comprises:
Further comprising a elongated tubular body comprising at least one sidewall defining said internal reservoir;
The sidewall further defining a hemispherical portion in the internal reservoir that is proximal to the first end of the body and is complementary to the hemispherical surface profile of the piston. 17. The method of claim 16,
The barrel comprises:
Further comprising a radially inwardly extending ledge in the internal reservoir adjacent the hemispherical portion, the sidewall having a substantially uniform thickness at the proximal end, whereby the position of the radially inwardly extending ledge And is visible to the outside of the body by a corresponding radially outwardly extending ledge. 10. The method of claim 9,
Further comprising a hot melt adhesive disposed within the internal reservoir. As a dispensing method of a hot melt adhesive,
Heating the dispensing syringe to liquefy the hot melt adhesive disposed within the internal reservoir of the dispensing syringe, wherein the dispensing syringe comprises:
A barrel having a first end and a second end and defining the internal reservoir,
A dispensing tip proximal to the first end of the barrel,
An outlet in fluid communication with the internal reservoir, and
A piston slidably disposed within the internal reservoir,
Wherein at least a portion of at least one of the barrel or the dispensing tip comprises a material selected to maintain the operational structural integrity of the dispensing syringe at a temperature of greater than about 150 占 폚; And
And moving the piston in a direction toward the dispensing tip to dispense the hot melt adhesive from the outlet. 20. The method of claim 19,
Wherein the dispensing syringe comprises:
A luer coupling at the first end of the barrel and adapted to receive the dispensing tip, the luer coupling comprising an outlet orifice and an outlet passage in fluid communication between the outlet orifice and the reservoir, the outlet passage having an axial length Further comprising the Luer coupling;
Wherein the piston has a first end and a second end and the first end extends along a central axis to distribute fluid from the first end of the barrel as the piston moves toward the first end of the barrel Having a generally hemispherical surface profile with an elongated apex; And
Wherein at least a portion of at least one of the barrel, the piston, or the luer coupling comprises a material selected to maintain the operational structural integrity of the dispensing syringe at a temperature of greater than about 150 占 폚.

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