DISPENSER AND MIXER FOR DISPOSABLE CARTRIDGES

Abstract

A dynamic mixer attachment is disclosed, which is adapted for use with conventional multi-component cartridges. The mixer has dispensing and drive axes that are offset relative to each other to enable use of the mixer with conventional multi-component cartridges. Also disclosed is a dispenser adapted for use with the mixer attachment and conventional multi-component cartridges.

Claims

1. A mixer for attachment to a cartridge holding two or more viscous materials to mix materials dispensed from the cartridge, the mixer comprising: a mixer housing defining an inlet for the viscous materials to be mixed, an outlet and a flow path for the viscous materials between the inlet and the outlet; a mixing element configured to rotate in the flow path between the inlet and the outlet about a mixer axis to mix the viscous materials flowing from the inlet to the outlet; and a transmission element defining a coupling configured to couple to a drive shaft and coupled to the mixing element to transmit a driving torque from the coupling to the mixing element, the transmission element being configured to rotate about a drive axis off-set from the mixer axis.

2. The mixer as claimed in claim 1, wherein the mixer and drive axes are substantially parallel to each other.

3. The mixer as claimed in claim 1, wherein the mixer housing defines an elongate mixing conduit in which the mixing element is disposed and comprises a back plate defining the inlet ports.

4. The mixer as claimed in claim 3, wherein the mixer housing comprises a lateral portion extending laterally from the elongate mixing conduit, and the transmission element is disposed in the lateral portion.

5. The mixer as claimed in claim 4, wherein the mixing element and the transmission element are each journalled in a respective bushing in the back plate.

6. The mixer as claimed in claim 3, wherein a first moulding comprises the elongate mixing conduit and lateral portion and a second moulding comprises the back plate, the mixer housing being configured to be assembled from the first and second mouldings.

7. A dispenser comprising: a body portion housing a drive mechanism configured to drive a plunger into a cartridge held relative to the drive mechanism; a cartridge holder configured to hold a cartridge in a cartridge accepting space relative to the drive mechanism; and a drive shaft having a coupling at one end configured to engage a mixer coupled to a cartridge held in the cartridge accepting space, the drive shaft being disposed to a side of the cartridge accepting space.

8. The dispenser as claimed in claim 7, wherein the dispenser is configured for hand-held operation.

9. The dispenser as claimed in claim 8, wherein the body portion is shaped as a handle to facilitate the hand-held operation of the dispenser.

10. The dispenser as claimed in claim 7, wherein the drive shaft and drive mechanism are driven independently.

11. dispenser as claimed in any one of claim 7, wherein the drive shaft and drive mechanism are each driven by a respective electric motor.

12. The dispenser as claimed in claim 7, wherein the cartridge holder comprises a front plate defining an opening for accepting a neck of the cartridge there through and the drive shaft is disposed through the front plate to engage a mixer coupled to the cartridge held in the cartridge holder.

13. A dispenser, comprising: a body portion housing a drive mechanism configured to drive a plunger into a cartridge held relative to the drive mechanism; a cartridge holder configured to hold a cartridge in a cartridge accepting space relative to the drive mechanism; and a drive shaft having a coupling at one end configured to engage a mixer coupled to a cartridge held in the cartridge accepting space, the drive shaft being disposed to a side of the cartridge accepting space, the dispenser configured to drive a mixer as claimed in claim 1.

14. A dispenser configured to dispense two or more materials from a cartridge through a mixer as claimed in claim 1 and configured to drive the mixer.

15. A kit of parts comprising a mixer as claimed in claim 1 and a dispenser, the dispenser comprising a body portion housing a drive mechanism configured to drive a plunger into a cartridge held relative to the drive mechanism, a cartridge holder configured to hold a cartridge in a cartridge accepting space relative to the drive mechanism, and a drive shaft having a coupling at one end configured to engage a mixer coupled to a cartridge held in the cartridge accepting space, the drive shaft being disposed to a side of the cartridge accepting space.

16. A dispenser comprising: a body portion housing a first drive mechanism configured to drive a plunger into a cartridge held relative to the body portion and a second drive mechanism configured to drive a drive shaft, the drive shaft being configured to engage a mixer for mixing viscous material dispensed from a cartridge held relative to the body portion; a cartridge holder coupled to the body portion to configured to hold a cartridge relative to the body portion, the body portion comprising a handle portion configured to be held by a user to operate the dispenser; a rear portion extending from the handle portion away from the cartridge holder and housing a first electric motor configured to drive the first drive mechanism; and a guard portion extending in a direction along the handle portion between the handle portion and the cartridge holder, the guard portion housing a second electric motor configured to drive the second drive mechanism, the handle portion and guard portion defining a space configured to accept a hand of the user of the dispenser therebetween.

17. The dispenser as claimed in claim 16, wherein the handle portion and guard portion are joined at one end by a common portion to which the cartridge holder is coupled and at another, opposed, end by a bottom portion, the space being defined between the bottom portion, handle portion and guard portion.

18. The dispenser as claimed in claim 17, wherein the bottom portion is configured to accept a battery to power the dispenser.

Description

DESCRIPTION OF THE DRAWINGS

[0026] The invention will be explained in more detail hereinafter with reference to the drawings.

[0027] FIG. 1 illustrates a dispenser loaded with a cartridge and mixer;

[0028] FIG. 2 illustrates the dispenser of FIG. 1 without the cartridge and mixer;

[0029] FIG. 3 illustrates an exploded view of the mixer and a front portion of the dispenser loaded with the cartridge;

[0030] FIG. 4 is a rear view of the mixer with a first arrangement for engaging the cartridge;

[0031] FIG. 5 is a rear view of the mixer with an alternative arrangement for engaging the cartridge; and

[0032] FIG. 6 is a partially cut away view of the dispenser exposing arrangements for driving dispensing and mixing.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] With reference to FIGS. 1 and 2, a cartridge 2 houses a respective viscous material in each of two side-by-side barrels 4, each having an outlet port in a neck of the cartridge 2. A dispenser 6 has a body portion 8 housing a drive mechanism for driving a set of two plungers 10, each for engaging a corresponding piston in a respective barrel 4. In use, the cartridge 2 is held relative to the body portion 8 (and hence the drive mechanism) in a cartridge holder 12. The cartridge holder 12 is formed by a shaped sheet metal member forming a cradle 14 and secured to the body portion 8 at a first end. At a second, opposed end, the cradle is closed by a front plate 16. A slot 18 in the front plate 16 accepts a neck of the cartridge 2 so that a shoulder of the cartridge 2 rests against the front plate 16 against the dispensing pressure applied to the viscous materials inside the cartridge 2 by the plungers 10.

[0034] A drive shaft 20 extends through the front plate 16 and provides a shaped coupling 22 at an end protruding from the front plate 16. The drive shaft extends longitudinally along a portion of the cradle 14 to one side (below) of the cradle. A mixer 24 is configured for mixing materials dispensed from the cartridge 2, driven by the drive shaft 20. In use, the mixer 24 is sealingly attached to the cartridge 2 and coupled to the drive shaft 20 for driving the mixer 24.

[0035] The body portion 8 comprises a handle portion 26 configured for being held by the hand of an operator and having actuating triggers 28 for actuation by fingers of a hand holding the handle portion 26. One of the actuating triggers 28, when actuated, is configured to drive the plunger forward into a cartridge held in the cartridge holder 12 and to cause rotation of the drive shaft 20, thereby causing mixing of materials dispensed from the cartridge as the plungers 10 apply a dispensing pressure to the materials in the cartridge. The other one of the actuating triggers 28, when actuated, is configured to cause the plungers 10 to be retracted. In this way, a user can hold the handle portion 26 in one hand and operate one of the actuating triggers 28 with one or more fingers of the same hand.

[0036] With reference to FIGS. 3 and 4, the mixer 24 comprises a mixer body 30 and a back plate 32, which are sealed together, for example by laser welding, to form a mixer housing. An adapter nut 34 is provided as a snap fit on the back plate 32 around a mixer inlet 36 in the back plate 32 for engaging a cartridge outlet in the neck of the cartridge 2. The mixer inlet is configured as an annular or frustoconical wall to seal around the neck. An outer wall of the mixer inlet 36 includes a neck, groove or other detent which accommodates a ridge on the adapter nut 34 to secure the adapter nut 34. The adapter nut 34 is rotatable relative to the back plate 32 to, in use, engage a thread on the neck of the cartridge 2, to secure the mixer 24 to a cartridge 2 held in the cartridge holder 12.

[0037] The mixer body 30 comprises an elongated front portion 38 extending from a dispensing end 40 of the mixer body 30 to a back portion 42, which forms a shoulder around the front portion 38. A mixing element 44 is disposed in the mixer body 30 with an elongated portion 46 extending inside the front portion 38 and a transmission portion 48 disposed in the back portion 42. The transmission portion 48 is shaped as a cogged wheel to provide a gear for engagement with a driving gear 50, shaped as another cogged wheel and disposed in a lateral portion 52 of the back portion 42 so as to mesh with the transmission portion 48.

[0038] The mixing element 44 comprises a shaft 54 extending longitudinally from the transmission portion 48. Mixing vanes 56 extend laterally from the shaft 54. The mixing element is journalled at one end by the front portion 38 disposed around the mixing vanes 56 and at the other end by the mixer inlet 36 disposed around a rearwards projection from the transmission portion 48, with the transmission portion 48 disposed against or adjacent the shoulder formed by the back portion 42 around the front portion 38. A flow path for materials from the neck of the cartridge 2 to the dispensing end 40 of the mixer body 30 is provided through the mixer inlet 36 and inlet openings 58 provided in the transmission portion 48 around the shaft 54.

[0039] Each of the back portion 42 of the mixer body 30 and the back plate 32 include a respective bushing 60, 62 to one side of the elongated front portion 38 for journaling a respective front and back journal portion 64 extending longitudinally from the driving gear 50, with the driving gear 50 rotatably held in place between the mixer body 30 and the back plate 32 with the journal portions 64 in the bushings 60, 62. The mixer body 30 and back plate 32 are arranged to seal around the journal portions or other portions of the driving gear 50 to prevent egress of materials from the cartridge 2 from the back portion 42 or back plate 32. The back journal portion 64 includes a coupling 66 for engagement by the coupling 22 of the drive shaft 20 to drive the driving gear 50 and extends rearwards through the respective bushing to provide access to the coupling 66 and enable the drive shaft 20 to be coupled to the coupling 66 when the mixer is in place.

[0040] The back portion 42 extends laterally from the elongated front portion 38 so that, in particular, the bushings 60, 62, and hence an axis of rotation of the driving gear 50, are offset from the elongated front portion 38 and mixer inlet 36 and hence from an axis of rotation of the mixing element 44. In this way, by laterally off-setting the axis of rotation (and coupling) of the driving gear 50 from the mixer inlet 36, the mixer 24 can be attached to a standard cartridge held in the dispenser 6 with the drive shaft 20 laterally off-set from the cartridge, for example below the cartridge as illustrated.

[0041] While, as depicted in FIG. 4, the adapter nut 34 has, in some embodiments, a thread 67 to engage a corresponding thread on a neck of a cartridge, it will of course be understood that other securing mechanisms are equally possible, for example a bayonet fixing 69 as depicted in FIG. 5, for engaging corresponding bayonet lugs on a neck of a cartridge. Of course, the location of the bayonet fixing and lugs may be interchangeable in accordance with various embodiments. Further, while embodiments described above with reference to FIG. 4 have been described as having a mixer inlet 36 configured as an annular or frustoconical wall to seal around the cartridge neck (and hence to seal around all outlets from the cartridge), other arrangements are of course equally possible. For example, in some embodiments the back plate 32 is configured with separate, individual mixer inlets 36, each one for engaging a corresponding outlet port of the cartridge. In some embodiments, the individual inlet ports are configured as prongs 71, each prong 71 engaging an inside wall of a cartridge outlet port with its outer wall, thereby reducing the risk of cross-contamination when the mixer is withdrawn from the cartridge. It will be understood that the configuration of the mixer inlet 36 and adapter nut 34 are independent of each other so that embodiments extend to various combinations of the features discussed above, that is for example inlet prongs with a threaded adapter nut, a single inlet opening with bayonet fixings, etc.

[0042] Returning to FIGS. 1 and 2, and with further reference to FIG. 6, the drive mechanism for the plungers 10 and mixer 24 is now described in further detail. Each plunger 10 is coupled to a push rod 68, which is slideably held in the body portion 8. The push rods 68 are joined at their rear ends by a cross piece 70. Each push rod 68 has a rack surface 72 engaging a pinion (not visible in FIG. 6) journalled by its pinion axis 74 in the body portion 8. A first electric motor 76 is disposed in a rear portion of the body portion 8 extending rearward from the handle 26 and coupled to a first gearbox 78. The first gearbox 78 is coupled to a system of bevel gears 80 (two of which are visible in FIG. 6) which in turn drive the pinion about its axis 74. Due to its engagement with the rack surface 72, rotation of the pinion drives the push rods 68, and hence the plungers 10 forwards or backwards, to apply dispensing pressure or retract the plungers, as needed. A guard portion 82 of the body portion 8 is disposed forward of the handle portion 26 and defines a space between the guard portion 82 and handle portion 26 in which the fingers of a user's hand can be accommodated. The guard portion 82 houses a second electric motor 84 coupled to a second gearbox 86, which transmits torque from the second electric motor 84 to the drive shaft 20. At a distal end of the body portion 8, distal to a common portion of the body portion and the first and second electric motors 76, 84, the handle portion 26 and guard portion 82 are joined by a battery holder portion 88 configured to provide a securing arrangement for securing a battery pack 90 to the body portion 8. The securing arrangement comprises a mechanical feature for engaging the battery pack 90 for securing it to the body portion 8, such as a slide rail and/or click fit, and electrically conductive contacts for engaging corresponding contacts on the battery pack 90, for example by a spring loaded engagement with one of the contacts acting as a spring.

[0043] A control system is coupled to the electric motors 76, 84 and the actuating triggers 28 discussed above to control energisation of the electric motors by applying a voltage from the battery pack 90 to the motor terminals. In some embodiments, a control variable selector 92 is incorporated with the body portion 8, for example as a rotary selector on top of the body portion 8 as depicted in FIGS. 1, 2 and 6. The control variable selector can be used by a user to set a corresponding control variable for the control system to control the electric motors accordingly. Control variables may include a dispensing speed, a dispensing torque, or a volume to be dispensed for a single actuation of one of the trigger actuators 28, by setting a corresponding value using the control variable selector 92. Alternatively, or additionally, control variables such as dispensing torque or speed can be set by a degree of actuation of one of the actuating triggers 28, for example an amount of depression of one of the actuating triggers 28 corresponding to a dispensing speed.

[0044] In use, a standard cartridge compatible with the dispenser 6 is inserted into the cartridge holder 12, for example by engaging a rear end of the cartridge with the plungers 10 and allowing the neck of the cartridge to drop into the slot 18. A mixer as described above is then coupled to the neck of the cartridge, to seal the mixer inlet to the cartridge outlet, and to the drive shaft 20 to allow the drive shaft 20 to drive the mixing element 44 inside the mixer 24. When a user then operates the dispenser, by activating one of the actuating triggers 28 and operating the trigger with one or more fingers of the same hand, the electric motor or motors are energized to activate the driving mechanism and drive shaft, causing viscous materials to be dispensed from the cartridge into the mixer and rotation of the mixing element in the mixer to mix the viscous materials as they flow through the mixer.

[0045] Having read the present disclosure, the skilled person will have gained a detailed understanding of the present invention and will appreciate that various modifications of the specific embodiment described above by way of example with reference to the drawings are possible, for example as indicated above, and fall within the scope of the appended claims. Thus, the specific description above is made by way of illustration and not limitation.