WO2001010305A1

WO2001010305A1 - Fluid dispenser

Info

Publication number: WO2001010305A1
Application number: PCT/GB2000/003048
Authority: WO
Inventors: Douglas Alastair Stewart; James Oscar Molloy; Michael Cameron Bainton
Original assignee: Tissuemed Limited
Priority date: 1999-08-06
Filing date: 2000-08-07
Publication date: 2001-02-15
Also published as: GB9918468D0; AU6457100A

Abstract

A dispenser (1) for fluid material comprises a body (30) defining a chamber for fluid material. The chamber has an outlet (31), and a piston (50) is mounted for sliding movement within the chamber along a first axis. The piston (50) is operably linked to a cam follower (54). An actuator (60) is pivotable about a second axis substantially orthogonal to the first axis, the actuator (60) being operably linked to a cam member (64) which bears upon the cam follower (54) to drive the piston (50) along the first axis so as to expel fluid material from the chamber through the outlet (31). A particularly important use of the dispenser (1) according to the invention is as an applicator for adhesive, particularly tissue adhesive.

Description

Title - Fluid Dispenser

This invention relates to a dispenser for fluid material, in particular to a pre-loaded dispenser for the controlled dispensing of a liquid. The dispenser is particularly suitable for the application of tissue adhesive.

Tissue adhesives are of increasing interest as an alternative to sutures for the closing of incisions or the bonding of tissues in surgical procedures. Such adhesives need to be applied in a controlled and precise manner.

Devices have been developed for the application of tissue adhesives. However, these tend to be mechanically complex and also rather bulky.

There has now been devised a fluid dispenser, of particular utility in the controlled dispensing of liquid materials, for example tissue adhesive, which overcomes or substantially mitigates the above-mentioned or other disadvantages of the prior art.

According to the invention, there is provided a dispenser for fluid material, said dispenser comprising a body defining a chamber for fluid material, said chamber having an outlet, a piston mounted for sliding movement within said chamber along a first axis, said piston being operably linked to a cam follower, and an actuator pivotable about a second axis substantially orthogonal to the first axis, said actuator being operably linked to a cam member which bears upon said cam follower to drive said piston along the first axis thereby to expel fluid material from said chamber through said outlet.

The dispenser according to the invention is advantageous primarily in that it is simple to operate and can be operated in a manner which permits considerable control and precision in the dispensing of the fluid material. Because the actuator is moved about an axis which is orthogonal to the axis of movement of the piston, it is possible for the dispenser to be held perfectly still while it is actuated, greatly assisting in precise dispensing of volumes of the fluid at an exact location, whilst at the same time the dispenser can be held and operated by one hand. In preferred embodiments, the dispenser can be manufactured inexpensively and can be preloaded with fluid material, further enhancing its ease of use.

A particularly important use of the dispenser according to the invention is as an applicator for adhesive, particularly tissue adhesive. Other fluids which may be dispensed from the dispenser include other forms of adhesive, eg so-called "superglues", as well as other curable liquids or resins, and high technology lubricants for precision mechanisms.

The capacity of the dispenser may be chosen to suit the particular application, but typical values are in the range 0.05ml to 50ml, or more.

The dispenser according to the invention is most preferably of elongate form. For many applications, including the application of tissue adhesive, the dispenser will be dimensioned and configured to be held in the manner of a pencil. In such a case, the actuator may be operated by gentle finger pressure.

The cam follower most preferably takes the form of a ramp or the like, which is acted upon by a suitable formation provided on the actuator.

Means are preferably provided to prevent unwanted actuation of the dispenser. Preferably, such means take the form of a component which can be releasably engaged with the actuator so as to interfere with the operation thereof. Most preferably, such a component forms part of a cap or sealing member which is engaged with the dispenser when the dispenser is not in use.

The outlet from the chamber preferably takes the form of a nozzle, the interior of the chamber being of tapered cross-section.

The actuator is preferably pivotally mounted by means of a flexible and resilient connection. The chamber outlet may take the form of a nozzle, which may be provided with a suitable closure, eg to retain fluid within the chamber prior to use and/or to permit repeated use (eg incremental dosing of the fluid).

Alternatively, the outlet may initially be sealed and the dispenser may be used in conjunction with a tip unit incorporating a needle which pierces the seal when the tip unit is fitted to the dispenser. The seal may take the form of a septum, which is preferably formed integrally with the outlet walls. In such cases, the outlet is preferably formed in a part of the dispenser which constitutes a luer lock fitting that cooperates with a mating formation on the tip unit.

The tip unit may have any one of many different forms. For example, the length of the needle which projects externally from the tip unit may vary considerably, eg from a few millimetres to more than one metre. The diameter of the needle may also vary, eg from 0.2mm to 5mm or more. The needle may be rigid or flexible. For instance, a long, thin, flexible tip may be suitable for endoscopic type applications and a bendable tip may be useful in applying the fluid to loci which are difficult to access. The tip unit may also be configured to facilitate application of the fluid as a spray. The needle may take the form of a catheter or cannula, and may be tipped with a brush or have another suitable form for spreading of the fluid as it is dispensed. The needle may terminate in a connector or in a resealable fitting, eg with a luer lock cap.

Different tip units, with needles of different forms, may be fitted to the dispenser in succession to suit different application conditions. The dispenser may also be fitted into a spray system in the manner of a cartridge, fluid being dispensed either through depression of the actuator or by the spray system acting directly upon the piston.

The dispenser is most preferably manufactured in plastics materials, and may comprise a relatively small number of injection moulded components which can be simply and readily assembled to form the dispenser. The dispenser is most preferably pre-loaded with the fluid material to be dispensed. By this is meant that the material is loaded into the dispenser during the manufacturing process.

The dispenser may be provided with closure means by which the outlet can be closed following use. The dispenser may therefore be susceptible of repeated use until the supply of fluid material is exhausted. Alternatively, the dispenser may be intended for single use only. In either case, the dispenser may be a disposable item, being discarded after use.

Particularly where the dispenser is for use in a clinical or surgical environment it may be supplied in a secondary packaging to ensure sterility.

The invention will now be described in greater detail, by way of example only, with reference to the accompanying drawings, in which

Figure 1(a) shows a side view, in section and showing hidden detail, of a first embodiment of an applicator for tissue adhesive according to the invention, in the configuration in which it is supplied;

Figure 1(b) is a plan view, again in section and showing hidden detail, of the applicator of Figure 1(a);

Figure 2(a) is a view similar to Figure 1(a) with the applicator in the configuration in which it is used;

Figure 2(b) is a view similar to Figure 1(b) with the applicator in the configuration of Figure 2(a);

Figure 3(a) is a side view in section of an applicator body forming part of the applicator of Figure 1(a);

Figure 3(b) is a plan view of the body of Figure 3(a); Figure 4(a) is a side view in section of an applicator cap forming part of the applicator of Figure 1(a);

Figure 4(b) is a plan view of the applicator cap of Figure 4(a);

Figure 5(a) is a side view in section of a plunger forming part of the applicator of Figure 1(a);

Figure 5(b) is a side view of the plunger of Figure 5(a);

Figure 5(c) is a plan view in section of the plunger of Figure 5(a);

Figure 6(a) is a side view of an actuator forming part of the applicator of Figure 1(a);

Figure 6(b) is a plan view of the actuator of Figure 6(a);

Figure 7 is a view similar to Figure 1(a) of a second embodiment of an applicator for tissue adhesive according to the invention, in the configuration in which it is supplied; and

Figure 8 is a side view showing hidden detail of a tip unit for use with the applicator of Figure 7.

Referring first to the embodiment of Figures 1 to 6, Figure 1 shows a pre-loaded, disposable applicator for tissue adhesive, generally designated 1. The applicator 1 comprises four components:

- an applicator body 30; - a cap 40;

- a plunger 50; and

- an actuator 60. All four of these components 30,40,50,60 are injection moulded in suitable plastics material. They are described in more detail below.

Body 30 - see Figure 3

The body 30 is of generally cylindrical form, being fully open at one end (the right hand end as viewed in Figure 3). At the other end the body 30 is tapered to form a pointed nozzle 31. The internal bore of the nozzle 31 is decreased stepwise to define three bores with progressively smaller cross-sectional areas 32,33,34.

The top part of the body 30 is provided at the right hand end as viewed in Figure 3 with a slot 35 which extends from the open end of the body 30 approximately halfway to the nozzle 31. The slot 35 is of a form and dimensions adapted to receive the actuator 50 in the manner described below.

Extending from the end of the slot 35, a short recess 36 is provided in the internal surface of the body 30. The recess 36 provides an air evacuation path when the actuator 1 is assembled, again as described below. The recess 36 is shown as hidden detail in Figure 3(b).

A circular groove 37 is provided around the neck of the nozzle 31 to provide a snap fit with the cap 40, again as described below.

Cap 40 - see Figure 4

The cap 40 is open at the right hand end as viewed in Figure 4. An annular rib 41 is provided around the internal surface of the cap 40, near the open end, the cap 40 being dimensioned such that when it is fitted over the nozzle 31 the rib 41 engages in the groove 37. At the same time, the end of the nozzle 31 is received closely within a terminal internal portion 42 of the cap 40, an inwardly-directed projection 43 at the end of that portion 42 sealing the open end of the nozzle 31. A locking bar 44 extends from the top edge of the open end of the cap 40 and engages the actuator 60 in a manner described below.

Plunger 50 - see Figure 5

The plunger 50 comprises a central, sealing portion 51 of circular cross-section which is dimensioned to fit closely within the interior of the body 30. A resilient, forwardly-projecting peripheral skirt 52 is formed integrally with the plunger 50 and serves, in use, to sealingly engage the internal wall of the body 30. A nose 53 also projects forwardly from the central portion 51 of the plunger 50. The part of the nose 53 which is adjacent to the central portion 51 is of cylindrical form, the forward part of the nose 53 having a tapered shape corresponding approximately to the internal shape of the tapered part of the body 30.

To the rear of the central portion 51 , the plunger 50 has a generally cylindrical form, save that a ramp 54 is provided. The ramp 54 extends downwards and rearwardly from the top of the plunger 50, at an angle of approximately 45°.

Actuator 60 - see Figure 6

The actuator 60 comprises a closure plug 61 and an actuator button 62 which are formed integrally and connected by a flexible, U-shaped web 63. A planar cam projection 64 depends downwardly from the underside of the button 62.

A first part 65 of the plug 61 is dimensioned to fit closely within, and close, the open end of the body 30. A pair of lugs 66 are formed in the upper part of this first part 65 which engage correspondingly shaped parts of the slot 35 in the body 30 when the plug 61 is inserted into the body 30.

A rearwardly-projecting extension 66 is provided on the plug 61 , the extension 66 having an annular groove 67 which serves to retain the cap 40 when the latter is removed during use. Assembly of the Applicator 1

The applicator 1 is assembled as follows:

The cap 40 is fitted over the nozzle end 31 of the body 30.

A metered quantity of liquid (in this case tissue adhesive) is introduced into the body 30.

The plunger 50 is introduced into the body 30, with the ramp 54 aligned with the slot 35 and moved forward until the plunger 50 reaches the position shown in Figure 1 , ie until the flexible skirt 52 contacts the internal surface of the body 30 just beyond the recess 36. Until the skirt 52 reaches this position, air in the space between the plunger 50 and the liquid held in the body 30 can escape via the slot 35 and recess 36.

Finally, the actuator 60 is introduced into the body 30 until the plug 61 seals the open end of the body 30. As the actuator 60 is pushed into this position the actuator button 62 rides up over the locking bar 44, causing the web 63 to flex.

The completed assembly has the configuration shown in Figure 1 , with the cam projection 64 resting on the upper end of the ramp 54 and with the button 62 locked against movement towards the body 30 by the locking bar 44.

The assembled applicator 1 may then, if necessary or desired, be encapsulated in sealed packaging.

Use of the Applicator 1

When it is desired to use the applicator 1 , eg during the course of a surgical procedure, the applicator 1 is first removed from any packaging. The cap 40 is removed from the body 30. The cap 30 may be discarded or may be fitted over the extension 66, the rib 41 engaging the groove 67 to hold the cap 40 in place (see Figure 2). With the cap 40 fitted in this fashion, the length of the applicator 1 is effectively increased (which makes it somewhat easier to hold and operate) and the cap 40 is retained securely for subsequent re-fitting over the nozzle 31.

With the cap 40 removed from the body 30, the button 62 may be depressed by the user exerting finger pressure upon it. This causes the cam projection 64 to bear against the ramp 54 and drive the plunger 50 forwards. This is turn causes liquid to be dispensed from the end of the nozzle 31.

The correspondence in shape between the nose 53 and the internal bore of the nozzle 31 means that the rate at which liquid is expelled is optimised.

After use, if any adhesive remains in the applicator 1 , the cap 40 may be replaced over the nozzle 31 , once again sealing the nozzle 31 and locking the button 62.

Adhesive is dispensed from the applicator 1 in a bead with a size determined principally by the dimensions of the bore of the terminal part of the nozzle 31. As shown in Figure 2, that is the bore 34. If it is desired that the adhesive should be dispensed in a larger bead, the end of the nozzle 31 may be cut off, eg on the line X-X in Figure 3(a) so that the effective bore is the bore 33. A yet greater effective bore may be achieved by cutting off the end of the nozzle on the line Y-Y. It will be appreciated, however, that in such cases the nozzle 31 cannot then be fully re- sealed by reapplication of the cap 40 to the body 30.

Referring now to the embodiment of the applicator shown in Figures 7 and 8, this is generally designated 100 and comprises three components:

- an applicator body 130

- a plunger 150

- an actuator 160 The applicator 100 is used in conjunction with a tip unit 170 (shown in Figure 8). As for the embodiment described above, the components 130,150,160 are injection moulded in plastics material. They are described in more detail as follows:

Body 130

The body 130 is generally of very similar form to the body 30 of the embodiment described above. It is generally cylindrical, being fully open at the right-hand (as viewed in Figure 7) end. At the other end, instead of being tapered to define a pointed nozzle as in the first embodiment, the left-hand end of the body 130 is shaped so as to constitute a male luer lock fitting 135. Also, the internal bore of the body 130 is closed by a pierceable seal 132.

In other respects the body 130 is similar to the body 30 of the first embodiment, and it cooperates with the actuator 160 and plunger 150 in a similar manner to that described above.

Plunger 150

The plunger 150 is of generally similar form to the plunger 50 of the first embodiment. The plunger 150 comprises a central, sealing portion 151 of circular cross-section which is dimensioned to fit closely within the interior of the body 130. A resilient, forwardly-projecting peripheral skirt 152 is formed integrally with the plunger 150 and serves, in use, to sealingly engage the internal wall of the body 150.

A generally cylindrical nose 153 projects forwardly from the central portion 151, the nose 153 being somewhat tapered at its tip. To the rear of the central portion 151, the plunger 150 is cylindrical, again having a ramp 154 similar to the ramp 54 of the first embodiment. Actuator 160

The actuator 160 is identical to the actuator 60. A closure plug 161 engages in, and closes, the open end of the body 130. An actuator button 162 is formed integrally with the plug 161 and cooperates with the ramp 154 in the same manner as described above in connection with the first embodiment.

Tip Unit 170

Where this embodiment differs from the first embodiment is in the fact that the applicator 100 is used in conjunction with an application-specific tip unit 170. The tip unit 170 illustrated (in Figure 8) comprises a female luer lock hub 171 which cooperates with the male fitting 135. The tip unit 170 incorporates a needle 172 with an angled, non-coring tip 173 which pierces the seal 132 when the tip unit 170 is fitted to the body 130.

The female luer lock hub 171 is most conveniently moulded in plastics material. The needle 172 may be of plastics material, in which case it may be formed integrally with the hub 171 , or may be metal, in which case the hub 171 is most preferably moulded about the needle 172.

Assembly and Use of the Applicator 100

Because the applicator 100 is supplied with the seal 132 intact, there is no need for a cap to be provided. Instead, a metered quantity of fluid (tissue adhesive) is introduced into the body 130, followed by the plunger 150, and the body 130 is then closed by fitting of the actuator 160 into the open end of the body 130. As for the first embodiment, the assembled actuator 100 may then be encapsulated in sealed packaging.

The tip unit 170 may also be supplied in sealed packaging, from which it is removed immediately prior to use. The tip unit 170 is fitted onto the male fitting 135 of the body 130 thereby piercing the seal 132 and permitting expression of adhesive from the body 130 by actuation of the button 162, as for the first embodiment.

Claims

1. A dispenser for fluid material, said dispenser comprising a body defining a chamber for fluid material, said chamber having an outlet, a piston mounted for sliding movement within said chamber along a first axis, said piston being operably linked to a cam follower, and an actuator pivotable about a second axis substantially orthogonal to the first axis, said actuator being operably linked to a cam member which bears upon said cam follower to drive said piston along the first axis thereby to expel fluid material from said chamber through said outlet.

2. A dispenser as claimed in Claim 1 , wherein the capacity of the dispenser is in the range 0.05ml to 50ml.

3. A dispenser as claimed in Claim 1 or Claim 2, which is of elongate form.

4. A dispenser as claimed in any preceding claim, wherein the cam follower takes the form of a ramp or the like, which is acted upon by a suitable formation provided on the actuator.

5. A dispenser as claimed in any preceding claim, wherein means are provided to prevent unwanted actuation of the dispenser.

6. A dispenser as claimed in Claim 5, wherein said means take the form of a component which can be releasably engaged with the actuator so as to interfere with the operation thereof.

7. A dispenser as claimed in Claim 6, wherein said component forms part of a cap or sealing member which is engaged with the dispenser when the dispenser is not in use.

8. A dispenser as claimed in any preceding claim, wherein the outlet from the chamber takes the form of a nozzle, the interior of the chamber being of tapered cross-section.

9. A dispenser as claimed in any preceding claim, wherein the actuator is pivotally mounted by means of a flexible and resilient connection.

10. A dispenser as claimed in any preceding claim, wherein the outlet is initially sealed and the dispenser is used in conjunction with a tip unit incorporating a needle which pierces the seal when the tip unit is fitted to the dispenser.

11. A dispenser as claimed in Claim 10, wherein the seal is in the form of a septum which is formed integrally with the outlet walls.

12. A dispenser as claimed in Claim 10 or Claim 11 , wherein the outlet is formed in a part of the dispenser which constitutes a luer lock fitting that cooperates with a mating formation on the tip unit.

13. A dispenser as claimed in any preceding claim, which is manufactured in plastics materials.

14. A dispenser as claimed in any preceding claim, which is pre-loaded with the fluid material to be dispensed.

15. A dispenser as claimed in any preceding claim, which contains a tissue adhesive.