Attachment mechanism for a haircare appliance

Abstract

An attachment mechanism 400 for removably connecting a haircare appliance (1000, fig.1(a)) main body (1005, fig.1(a)) with an attachment, comprising an actuator 410 with a first engagement surface 411

Description

BACKGROUND Haircare appliances are known which use a flow of air to style hair. Such appliances may be used with a variety of different attachments to achieve different hairstyles. For example, each attachment may have a different function such as drying or curling. SUMMARY According to a first aspect of the present invention, there is provided an attachment mechanism for removably connecting a main body of a haircare appliance with an attachment for the haircare appliance, wherein the attachment mechanism comprises: an actuator comprising a first engagement surface, and an interface portion removably couplable to the actuator, the interface portion comprising a second engagement surface which is angled relative to the first engagement surface; wherein the actuator is moveable between an open position and a locking position (which may also be referred to herein as a closed position); and the actuator is biased towards the locking position such that, when the interface portion is coupled to the actuator, the first engagement surface and the second engagement surface are mutually engaged to prevent the interface portion being uncoupled from the actuator, and such that the biasing force provides a reaction force between the first surface and the second surface which acts to pull the actuator and the interface portion towards one another. By being provided in this way, the attachment mechanism ensures that there is a strong and stable connection between the actuator and the interface portion, which in turn produces a strong and stable connection between a main body of a haircare appliance and an associated attachment, such that the attachment is more securely held in place. For example, this may help ensure that the attachment stays in position when in use for consistent hair styling, as well as help prevent accidental removal of the attachment. Optional features of the invention set out are applicable singly or in any combination with any aspect of the invention. Optionally, the first engagement surface may be a surface of a first engagement feature, and the first engagement feature may comprise a protrusion from the actuator. For example, the first engagement feature may comprise a wedge-shaped protrusion. In other embodiments,, the first engagement surface may be a surface of a first engagement feature, and the first engagement feature may comprise a recession into the actuator (e.g., such as a groove or a slot or the like). By being provided as a wedge-shaped protrusion, the first engagement feature may have a first surface (e.g., a lower surface) which may act as a first engagement surface, and second surface (e.g., an upper surface) which is engageable by a second engagement features as described below with respect to a second aspect of the present invention in order to provide ‘push-to-lock’ operation of the attachment mechanism, whereby a user is able to couple the interface portion with the actuator without rotation of either part. Optionally, the actuator may comprise a plurality of first engagement features, each first engagement feature having a respective first engagement surface. Providing a plurality of such first engagement features may enable the interface portion to be connected to the actuator in a plurality of different orientations (for example, but not limited to, a plurality of rotational orientations relative to the actuator). This may make the haircare appliance more ergonomic, as a user may have a greater number of options for connecting an attachment to the main body. A plurality of first engagement features may also strengthen the connection between the actuator and the interface portion by providing a plurality of connection points between the components. Optionally, the second engagement surface may be a surface of a second engagement feature, wherein second engagement feature may comprise a protrusion from the interface portion. In other embodiments, the second engagement surface may be a surface of a second engagement feature, wherein each second engagement feature may comprise a recess into the interface portion (e.g., such as a groove or a slot or the like). Optionally, the interface portion may comprise a plurality of second engagement features, each second engagement feature having a respective second engagement surface. Providing a plurality of such second engagement features may enable the interface portion to be connected to the actuator in a plurality of different orientations (for example, but not limited to, a plurality of rotational orientations relative to the actuator). This may make the haircare appliance more ergonomic, as a user may have a greater number of options for connecting an attachment to the main body. A plurality of second engagement features may also strengthen the connection between the actuator and the interface portion by providing a plurality of connection points between the components. For example, the number of second engagement features may be the same as the number of first engagement features, and they may be spaced apart in a like manner in order to form a one-to-one connection between first engagement features and second engagement features. Optionally, the actuator may be slidably mounted on a bearing surface, such as an annular bearing surface. The bearing surface may allow the actuator to move between open and locking positions without becoming misaligned or moving out of position relative to the other parts of the attachment mechanism. The bearing surface may also be configured to allow the actuator to move more easily and with less friction. In certain embodiments, the bearing surface may be connected (either directly or indirectly) to the main body. In other embodiments, the bearing surface may be connected (either directly or indirectly) to the attachment. In some embodiments, the attachment mechanism may comprise a seal which is applied to the bearing surface. In such arrangements, it will be appreciated that the seal (in particular, an upper face thereof), will provide a bearing surface, upon which the actuator is slidable for example. Optionally, the interface portion may be part of the attachment. However, in other embodiments, the interface portion may be part of the main body. Optionally, the actuator may comprise an outwardly directed protrusion which is operable by a user to move the actuator from the locking position to the open position for uncoupling the interface portion from the actuator. This may help improve the ease of use of the attachment mechanism. According to a second aspect of the present invention, there is provided a haircare appliance comprising a main body, an attachment which is removably connectable to the main body, and an attachment mechanism according to the first aspect of the present invention. The actuator may be mounted, either directly or indirectly, to either of the main body or the attachment, with the interface portion being mounted, either directly or indirectly, to either of the attachment or the main body, respectively. According to a third aspect of the present invention, there is provided an attachment mechanism for removably connecting a main body of a haircare appliance with an attachment for the haircare appliance, wherein the attachment mechanism comprises: an actuator comprising a first engagement feature, and an interface portion removably couplable to the actuator, the interface portion comprising a second engagement feature; wherein the actuator is moveable between an open position and a locking position; and the actuator is biased towards the locking position such that, as the interface portion is moved into contact for coupling with the actuator, the second engagement feature engages the first engagement feature to move the actuator towards the open position, and, when the interface portion is coupled to the actuator, the actuator is in the locking position such that the first engagement feature and the second engagement feature are mutually engaged to prevent the interface portion being uncoupled from the actuator. In this way, the second aspect of the present invention provides an attachment mechanism in which a ‘push to lock’ mode of engaging the interface portion with the actuator is enabled, whereby a user simply needs to push the interface portion and the actuator together to couple them, and the user is not required to rotate either the actuator or the interface portion. This may enable an ergonomic haircare appliance to be implemented, in which it is easier for a user to connect an attachment to a main body of the appliance. Optionally, the attachment mechanism may comprise a guiding channel for aligning the first engagement feature and the second engagement feature when the interface portion is moved into contact with the actuator. This may make the attachment mechanism easier to use, as the user may use the guiding channel to ensure that the first and second engagement features are aligned when coupling the interface portion with the actuator. Optionally, the actuator may be movable relative to the guiding channel. Optionally, the second engagement feature may be at least partially positioned within the guiding channel when the interface portion is coupled to the actuator, such that the interface portion is held in a rotational position relative to the locking position of the actuator. In this way, the guiding channel may help to ensure that the interface portion and the actuator portion are stably and securely coupled to one another, which may provide a more secure connection of an attachment to a main body of a haircare appliance. Optionally, the guiding channel may be formed in an outer collar. For example, the outer collar may house other components of the attachment mechanism, such as the actuator and the bearing surface. In some embodiments the outer collar may be fixed to the main body of the haircare appliance, but in other embodiments the outer collar may be fixed to an attachment. Optionally, the first engagement feature and the second engagement feature have corresponding angled surfaces such that, as the interface portion is moved into contact with the actuator, the actuator is moved towards the open position. For example, one or both of the angled surfaces may comprise a curved or rounded surface. Optionally, the actuator may be slidably mounted on a bearing surface. The bearing surface may allow the actuator to move between open and locking positions without becoming misaligned or moving out of position relative to the other parts of the attachment mechanism. The bearing surface may also be configured to allow the actuator to move more easily and with less friction. In some embodiments, the attachment mechanism may comprise a seal which is applied to the bearing surface. In such arrangements, it will be appreciated that the seal (in particular, an upper face thereof), will provide a bearing surface, upon which the actuator is slidable for example. In certain embodiments, the interface portion may be in contact with the bearing surface when the interface portion is coupled to the actuator. For example, part of the interface portion, such as a part of the second engagement feature, may be in contact with the bearing surface. By being provided in this way, the bearing surface may act as an additional support surface which supports the interface portion to provide further stability when the interface portion is coupled to the actuator. Optionally, the actuator may be annular and may comprise a plurality of first engagement features spaced about the circumference of the actuator. Providing a plurality of such first engagement features may enable the interface portion to be connected to the actuator in a plurality of different orientations (for example, but not limited to, a plurality of rotational orientations relative to the actuator). This may make the haircare appliance more ergonomic, as a user may have a greater number of options for connecting an attachment to the main body. A plurality of first engagement features may also strengthen the connection between the actuator and the interface portion by providing a plurality of connection points between the components. Optionally, each first engagement feature may comprise a protrusion from the actuator. For example, each first engagement feature may comprise a wedge-shaped protrusion. In other embodiments, each first engagement feature may comprise a recess into the actuator (e.g., such as a groove or a slot or the like). By being provided as a wedge-shaped protrusion, the first engagement feature may have a first surface (e.g., a lower surface) which may act as a first engagement surface as described above with respect to the first aspect of the present invention, and a second surface (e.g., an upper surface) which is engageable by the second engagement feature when the interface portion is moved into contact for coupling with the actuator in order to provide ‘push-to-lock’ operation of the attachment mechanism, whereby a user is able to couple the interface portion with the actuator without rotation of either part. Optionally, the interface portion may comprise a cylindrical interface surface and a plurality of second engagement features spaced about the circumference of the interface surface. Providing a plurality of such second engagement features may enable the interface portion to be connected to the actuator in a plurality of different orientations (for example, but not limited to, a plurality of rotational orientations relative to the actuator). This may make the haircare appliance more ergonomic, as a user may have a greater number of options for connecting an attachment to the main body. A plurality of second engagement features may also strengthen the connection between the actuator and the interface portion by providing a plurality of connection points between the components. For example, the number of second engagement features may be the same as the number of first engagement features, and they may be spaced apart in a like manner in order to form a one-to-one connection between first engagement features and second engagement features. Optionally, the or each second engagement feature may comprise a protrusion from the interface portion. In other embodiments, the or each second engagement feature may comprise a recess into the interface portion (e.g., such as a groove or a slot or the like). Optionally, the second engagement feature may comprise a first portion configured (e.g., shaped, located) to engage the first engagement feature, and a second portion configured (e.g., shaped, located) to engage the guiding channel. In certain embodiments, the first portion and the second portion may be portions of a single radial protrusion from the interface portion. In other embodiments, the first portion and the second portion may comprise independent radial protrusions from the interface portion. Optionally, the actuator may comprise an outwardly directed protrusion which is operable by a user to move the actuator from the locking position to the open position for uncoupling the interface portion from the actuator. This may help improve the ease of use of the attachment mechanism. According to a fourth aspect of the present invention, there is provided a haircare appliance comprising a main body, and attachment which is removably connectable to the main body, and an attachment mechanism according to the third aspect of the present invention. The actuator may be mounted, either directly or indirectly, to either of the main body or the attachment, with the interface portion being mounted, either directly or indirectly, to either of the attachment or the main body, respectively. According to a fifth aspect of the present invention, there is provided a haircare appliance comprising a main body, an attachment, and an attachment mechanism for removably connecting the attachment to the main body; wherein the main body has an outer wall, the outer wall having an elliptical cross-sectional shape perpendicular to its longitudinal axis; and the attachment mechanism comprises an annular actuator, the actuator being positioned within the outer wall and rotatable about the longitudinal axis of the main body. In this way, the third aspect of the present invention provides a haircare appliance which is ergonomically designed to be easier and more comfortable for a user to hold due to the elliptical cross-section of the outer wall. The length of the haircare appliance is also reduced due to the decreased longitudinal space required for the attachment mechanism as a result of the actuator being annular and rotatable about the longitudinal axis of the attachment mechanism. Optionally, the actuator may comprise a plurality of first engagement features spaced about the circumference of the actuator. Providing a plurality of such first engagement features may enable the attachment to be connected to the main body in a plurality of different orientations (for example, but not limited to, a plurality of rotational orientations relative to the actuator). This may make the haircare appliance more ergonomic, as a user may have a greater number of options for connecting an attachment to the main body. A plurality of first engagement features may also strengthen the connection between the main body and the attachment by providing a plurality of connection points between the components. For example, the plurality of first engagement features may comprise at least two engagement features, such as three engagement features, or four first engagement features. Optionally, the plurality of first engagement features may be evenly spaced about the circumference of the actuator. For example, where the plurality of first engagement features comprises four first engagement features, these may be positioned at locations which are 90° separated from one another about the circumference of the actuator. Such even spacing may help provide a stable connection between the main body and the attachment, as well as providing rotational symmetry allowing the interface portion to be coupled to the actuator in a plurality of orientations. In certain embodiments wherein the plurality of first engagement features comprises four first engagement features, each first engagement feature may be positioned closer to a major axis of the outer wall cross-sectional shape than a minor axis of the outer wall cross-sectional shape. For example, the first engagement features may be arranged in two pairs wherein the spacing between first engagement features in a pair is less than the spacing between first engagement features in the other pair. In a particular example, within each pair the first engagement features may be spaced apart by about 60°, and the two pairs may be diametrically opposed to one another across the actuator. This may provide an arrangement wherein each first engagement feature is 30° offset from a major axis of the outer wall cross-sectional shape, for example. Being positioned closer to the major axis in this way may help to correctly align the main body and the attachment when they are connected by a user, as well as ensuring that the main body and the attachment are stably connected by positioning the connection points closer to the axis along which the attachment is likely to tilt relative to the main body. Such an arrangement also provides rotational symmetry of the actuator, such that the interface portion can be coupled to the actuator in a plurality of orientations. Optionally, each first engagement feature may comprise a protrusion from the actuator, such as a radial protrusion (e.g., having a wedge shape). In other embodiments, each first engagement feature may comprise a recess into the actuator (e.g., such as a groove or a slot or the like). Optionally, the attachment may comprise a cylindrical interface surface for coupling with the actuator. Optionally, the interface surface may comprise a plurality of second engagement features spaced about the circumference of the interface surface. Providing a plurality of such second engagement features may enable the interface portion to be connected to the actuator in a plurality of different orientations (for example, but not limited to, a plurality of rotational orientations relative to the actuator). This may make the haircare appliance more ergonomic, as a user may have a greater number of options for connecting an attachment to the main body. A plurality of second engagement features may also strengthen the connection between the actuator and the interface portion by providing a plurality of connection points between the components. For example, the number of second engagement features may be the same as the number of first engagement features, and they may be spaced apart in a like manner in order to form a one-to-one connection between first engagement features and second engagement features. Optionally, each second engagement feature may comprise a protrusion from the interface portion (e.g., a radial protrusion). In other embodiments, each second engagement feature may comprise a recess in the interface surface (e.g., such as a groove or a slot or the like). Optionally, the main body may comprise a circular opening in an end surface thereof for receiving the cylindrical interface surface of the attachment. For example, the circular opening may be formed in an outer collar, which may house components of the attachment mechanism such as the actuator and the bearing surface. Optionally, the circular opening may comprise a guiding channel on its inner surface to ensure that the attachment is correctly aligned with respect to the actuator for coupling, for example by helping align the first engagement feature and the second engagement feature when the interface portion is moved into contact with the actuator. This may make the attachment mechanism easier to use, as the user may use the guiding channel to ensure that the first and second engagement features are aligned when coupling the interface portion with the actuator. Optionally, the actuator may be slidably mounted on a bearing surface, such as an annular bearing surface. The bearing surface may allow the actuator to move between open and locking positions without becoming misaligned or moving out of position relative to the other parts of the attachment mechanism. The bearing surface may also be configured to allow the actuator to move more easily and with less friction. In some embodiments, the attachment mechanism may comprise a seal which is applied to the bearing surface. In such arrangements, it will be appreciated that the seal (in particular, an upper face thereof), will provide a bearing surface, upon which the actuator is slidable for example. Optionally, the actuator may be rotatable between a locking position and an open position. For example, the locking position may be suitable for ensuring that the attachment is firmly connected to the main body, and the open position may allow a user to remove the attachment from the main body. Optionally, the haircare appliance may further comprise a biasing element configured to urge the rotatable actuator towards the locking position. This may help to ensure that the attachment cannot accidentally be removed or displaced from the main body. Optionally, the biasing element may be configured to bias the rotatable actuator relative to the bearing surface. Optionally, the actuator may comprise an outwardly directed protrusion which is operable by a user to move the actuator from the locking position to the open position. This may help improve the ease of use of the attachment mechanism, and allows the attachment to be uncoupled from the main body. According to a sixth aspect of the present invention, there is provided an attachment mechanism for removably connecting a main body of a haircare appliance with an attachment for the haircare appliance, wherein the attachment mechanism comprises: an actuator comprising a first engagement surface, an interface portion removably couplable to the actuator, the interface portion comprising a second engagement surface, and a resiliently deformable seal; wherein the actuator is moveable between an open position and a locking position; the actuator is biased towards the locking position such that, when the interface portion is coupled to the actuator, the first engagement surface and the second engagement surface oppose one another; and when the interface portion is coupled to the actuator, the resiliently deformable seal is in contact with the interface portion to apply a biasing force to the interface portion and thereby bias the second engagement surface towards the first engagement surface such that the first engagement surface and second engagement surface are mutually engaged to prevent the interface portion being uncoupled from the actuator. By being provided in this way, the attachment mechanism may ensure that there is a strong and stable connection between the actuator and the interface portion, which in turn produces a strong and stable connection between a main body of a haircare appliance and an associated attachment, such that the attachment may be more securely held in place. For example, this may help ensure that the attachment stays in position when in use for consistent hair styling, as well as help prevent accidental removal of the attachment. In particular, the connection may be improved by the presence of the resiliently deformable seal which may act to firmly engage the first engagement surface with the second engagement surface, by applying the biasing force to the interface portion. Optionally, the resiliently deformable seal may comprise a body portion and a protruding flange, which may be angled relative to the body portion, arranged such that, when the interface portion is coupled to the actuator, the protruding flange is in contact with the interface portion to apply a biasing force to the interface portion and thereby bias the second engagement surface towards the first engagement surface. For example, the protruding flange may be angled relative to the body portion, and may be arranged at an angle of less than 90°, such as around 45°. Of course, it will be appreciated that the protruding flange may be provided in any suitable manner. By being configured in this way, the shape of the resiliently deformable seal itself may contribute to the manner in which the resiliently deformable seal applies a biasing force to the interface portion, further strengthening a connection between the actuator and the interface portion, for example to help ensure that an attachment is securely attached to a main body. Optionally, the resiliently deformable seal may be made of a silicone rubber material. The material of the resiliently deformable seal may thereby contribute to the manner in which the resiliently deformable seal applies a biasing force to the interface portion, further strengthening a connection between the actuator and the interface portion, for example to help ensure that an attachment is securely attached to a main body. Optionally, the first engagement surface and the second engagement surface may be configured such that, when the interface portion is coupled to the actuator, the first engagement surface and the second engagement surface are substantially parallel to one another. As well as ensuring firm engagement between the first engagement surface and the second engagement surface, such an arrangement may assist in manufacturing wherein the first engagement surface and the second engagement surface may be used as datum references. In particular, by providing the first engagement surface and second engagement surface such that they are parallel to one another when the interface portion is coupled to the actuator, it may be easier to determine that the interface portion and the actuator are manufactured to within predetermined manufacturing tolerances. Optionally, in certain embodiments, the first engagement surface may comprise a first ramped portion which is angled relative to the second engagement surface, and / or the second engagement surface may comprise a second ramped portion which is angled relative to the first engagement surface; the first ramped portion and / or second ramped portion for aligning the first engagement surface and the second engagement surface when the interface portion is coupled to the actuator and the actuator moves towards the locking position. Such an arrangement may help to ensure that the engagement surfaces are aligned, particularly as the actuator moves towards the locking position. For example, where the first engagement surface is a surface of a first engagement portion and the second engagement surface is a surface of a second engagement portion, this may ensure that the engagement portions are properly aligned and do not abut each other as the actuator moves towards the locking position. Optionally, the first engagement surface may be a surface of a first engagement feature, and the first engagement feature may comprise a protrusion from the actuator. For example, the first engagement feature may comprise a wedge-shaped protrusion. In other embodiments, the first engagement surface may be a surface of a first engagement feature, and the first engagement feature may comprise a recess or recession into the actuator (e.g., such as a groove or a slot or the like). By being provided as a wedge-shaped protrusion, the first engagement feature may have a first surface (e.g., a lower surface) which may act as a first engagement surface, and second surface (e.g., an upper surface) which is engageable by a second engagement features as described herein in order to provide ‘push-to-lock’ operation of the attachment mechanism, whereby a user is able to couple the interface portion with the actuator without requiring a user to rotate either part. Optionally, the actuator may comprise a plurality of first engagement features, each first engagement feature having a respective first engagement surface. Providing a plurality of such first engagement features may enable the interface portion to be connected to the actuator in a plurality of different orientations (for example, but not limited to, a plurality of rotational orientations relative to the actuator). This may make the haircare appliance more ergonomic, as a user may have a greater number of options for connecting an attachment to the main body. A plurality of first engagement features may also strengthen the connection between the actuator and the interface portion by providing a plurality of connection points between the components. Optionally, the second engagement surface may be a surface of a second engagement feature, wherein second engagement feature may comprise a protrusion from the interface portion. In other embodiments, the second engagement surface may be a surface of a second engagement feature, wherein each second engagement feature may comprise a recess into the interface portion (e.g., such as a groove or a slot or the like). Optionally, the interface portion may comprise a plurality of second engagement features, each second engagement feature having a respective second engagement surface. Providing a plurality of such second engagement features may enable the interface portion to be connected to the actuator in a plurality of different orientations (for example, but not limited to, a plurality of rotational orientations relative to the actuator). This may make the haircare appliance more ergonomic, as a user may have a greater number of options for connecting an attachment to the main body. A plurality of second engagement features may also strengthen the connection between the actuator and the interface portion by providing a plurality of connection points between the components. For example, the number of second engagement features may be the same as the number of first engagement features, and they may be spaced apart in a like manner in order to form a one-to-one connection between first engagement features and second engagement features. Optionally, the actuator may be slidably mounted on a bearing surface, such as an annular bearing surface. The bearing surface may allow the actuator to move between open and locking positions without becoming misaligned or moving out of position relative to the other parts of the attachment mechanism. The bearing surface may also be configured to allow the actuator to move more easily and with less friction. Optionally, the actuator may comprise an outwardly directed protrusion which is operable by a user to move the actuator from the locking position to the open position for uncoupling the interface portion from the actuator. This may help improve the ease of use of the attachment mechanism. According to a seventh aspect of the present invention, there is a provided a haircare appliance comprising a main body, an attachment which is removable connectable to the main body, and an attachment mechanism according to the sixth aspect of the present invention. The actuator and the resiliently deformable seal may be mounted, either directly or indirectly, to either of the main body or the attachment, with the interface portion being mounted, either directly or indirectly, to either of the attachment or the main body, respectively. According to an eighth aspect of the present invention, there is provided an attachment mechanism for removably connecting a main body of a haircare appliance with an attachment for the haircare appliance, wherein the attachment mechanism comprises: an actuator comprising a first engagement feature having a first engagement surface, and an interface portion removably couplable to the actuator, the interface portion comprising a second engagement feature having a second engagement surface; wherein the actuator is moveable between an open position and a locking position; and the actuator is biased towards the locking position such that, as the interface portion is moved into contact for coupling with the actuator, the second engagement feature engages the first engagement feature to move the actuator towards the open position, and, when the interface portion is coupled to the actuator, the actuator is in the locking position such that the first engagement surface and the second engagement surface oppose one another. In this way, the second aspect of the present invention provides an attachment mechanism in which a ‘push to lock’ mode of engaging the interface portion with the actuator is enabled, whereby a user simply needs to push the interface portion and the actuator together to couple them, and the user is not required to rotate either the actuator or the interface portion. This may enable an ergonomic haircare appliance to be implemented, in which it is easier for a user to connect an attachment to a main body of the appliance. Optionally, the attachment mechanism may further comprise a resiliently deformable seal, wherein when the interface portion is coupled to the actuator, the resiliently deformable seal is in contact with the interface portion to apply a biasing force to the interface portion and thereby bias the second engagement surface towards the first engagement surface such that the first engagement surface and second engagement surface are mutually engaged to prevent the interface portion being uncoupled from the actuator. By providing a resiliently deformable seal as part of the attachment mechanism, it may be ensured that there is a strong and stable connection between the actuator and the interface portion, which in turn produces a strong and stable connection between a main body of a haircare appliance and an associated attachment, such that the attachment is more securely held in place. For example, this may help ensure that the attachment stays in position when in use for consistent hair styling, as well as help prevent accidental removal of the attachment. In particular, the connection may be improved by the presence of the resiliently deformable seal which acts to firmly engage the first engagement surface with the second engagement surface, by applying the biasing force to the interface portion. Optionally, the resiliently deformable seal may comprise a body portion and a protruding flange which is angled relative to the body portion and arranged such that, when the interface portion is coupled to the actuator, the protruding flange is in contact with the interface portion to apply a biasing force to the interface portion and thereby bias the second engagement surface towards the first engagement surface. For example, the protruding flange may be angled relative to the body portion at an angle of less than 90°, such as around 45°. By being configured in this way, the shape of the resiliently deformable seal itself contributes to the manner in which the resiliently deformable seal applies a biasing force to the interface portion, further strengthening a connection between the actuator and the interface portion, for example to help ensure that an attachment is securely attached to a main body. Optionally, the resiliently deformable seal may be made of a silicone rubber material. The material of the resiliently deformable seal may thereby contribute to the manner in which the resiliently deformable seal applies a biasing force to the interface portion, further strengthening a connection between the actuator and the interface portion, for example to help ensure that an attachment is securely attached to a main body. Optionally, the attachment mechanism may comprise a guiding channel for aligning the first engagement feature and the second engagement feature when the interface portion is moved into contact with the actuator. This may make the attachment mechanism easier to use, as the user may use the guiding channel to ensure that the first and second engagement features are aligned when coupling the interface portion with the actuator. Optionally, the actuator may be moveable relative to the guiding channel. Optionally, the second engagement feature may be at least partially positioned within the guiding channel when the interface portion is coupled to the actuator, such that the interface portion is held in a rotational position relative to the locking position of the actuator. In this way, the guiding channel may help to ensure that the interface portion and the actuator portion are stably and securely coupled to one another, which may provide a more secure connection of an attachment to a main body of a haircare appliance. Optionally, the guiding channel may be formed in an outer collar. For example, the outer collar may house other components of the attachment mechanism, such as the actuator and the bearing surface. In some embodiments the outer collar may be fixed to the main body of the haircare appliance, but in other embodiments the outer collar may be fixed to an attachment. Optionally, the outer collar may comprise a flange arranged to abut a rim extending outwardly from the interface portion when the interface portion is coupled to the actuator. The flange may thereby improve the stability of the interface portion when connected to the actuator. Optionally, a surface of the flange and a surface of the rim which abut one another when the interface portion is coupled to the actuator are parallel to one another. Such an arrangement may assist in manufacturing wherein the surface of the flange and the surface of the interface portion may be used as datum references. In particular, by arranging these surfaces such that they are parallel to one another when the interface portion is coupled to the actuator, it may be easier to determine that the interface portion and the outer collar are manufactured to within predetermined manufacturing tolerances. Optionally, the first engagement feature and the second engagement feature have corresponding angled surfaces such that, as the interface portion is moved into contact with the actuator, the actuator is moved towards the open position. For example, one or both of the angled surfaces may comprise a curved or rounded surface. Optionally, the actuator may be slidably mounted on a bearing surface, such as an annular bearing surface. The bearing surface may allow the actuator to move between open and locking positions without becoming misaligned or moving out of position relative to the other parts of the attachment mechanism. The bearing surface may also be configured to allow the actuator to move more easily and with less friction. The bearing surface may be connected to the main body, for example. Optionally, the first engagement surface and the second engagement surface may be configured such that, when the interface portion is coupled to the actuator, the first engagement surface and the second engagement surface are substantially parallel to one another. As well as ensuring firm engagement between the first engagement surface and the second engagement surface, such an arrangement may assist in manufacturing wherein the first engagement surface and the second engagement surface may be used as datum references. In particular, by providing the first engagement surface and second engagement surface such that they are parallel to one another when the interface portion is coupled to the actuator, it may be easier to determine that the interface portion and the actuator are manufactured to within predetermined manufacturing tolerances. Optionally, in certain embodiments, the first engagement surface may comprise a first ramped portion which is angled relative to the second engagement surface, and / or the second engagement surface may comprise a second ramped portion which is angled relative to the first engagement surface; the first ramped portion and / or second ramped portion for aligning the first engagement surface and the second engagement surface when the interface portion is coupled to the actuator and the actuator moves towards the locking position. Such an arrangement may help to ensure that the engagement surfaces are aligned, particularly as the actuator moves towards the locking position. For example, where the first engagement surface is a surface of a first engagement portion and the second engagement surface is a surface of a second engagement portion, this may ensure that the engagement portions are properly aligned and do not abut each other as the actuator moves towards the locking position. Optionally, the actuator and may comprise a plurality of first engagement features spaced about the circumference of the actuator. Providing a plurality of such first engagement features may enable the interface portion to be connected to the actuator in a plurality of different orientations (for example, but not limited to, a plurality of rotational orientations relative to the actuator). This may make the haircare appliance more ergonomic, as a user may have a greater number of options for connecting an attachment to the main body. A plurality of first engagement features may also strengthen the connection between the actuator and the interface portion by providing a plurality of connection points between the components. Optionally, the actuator may be annular. For example, the plurality of first engagement features may be distributed around the circumference of the annular actuator. Optionally, each first engagement feature may comprise a protrusion from the actuator. For example, each first engagement feature may comprise a wedge-shaped protrusion. In other embodiments, each first engagement feature may comprise a recess into the actuator (e.g., such as a groove or a slot or the like). By being provided as a wedge-shaped protrusion, the first engagement feature may have a first surface (e.g., a lower surface) which may act as a first engagement surface as described above with respect to the first aspect of the present invention, and a second surface (e.g., an upper surface) which is engageable by the second engagement feature when the interface portion is moved into contact for coupling with the actuator in order to provide ‘push-to-lock’ operation of the attachment mechanism, whereby a user is able to couple the interface portion with the actuator without rotation of either part. Optionally, the interface portion may comprise a plurality of second engagement features spaced about the circumference of the interface surface. Providing a plurality of such second engagement features may enable the interface portion to be connected to the actuator in a plurality of different orientations (for example, but not limited to, a plurality of rotational orientations relative to the actuator). This may make the haircare appliance more ergonomic, as a user may have a greater number of options for connecting an attachment to the main body. A plurality of second engagement features may also strengthen the connection between the actuator and the interface portion by providing a plurality of connection points between the components. For example, the number of second engagement features may be the same as the number of first engagement features, and they may be spaced apart in a like manner in order to form a one-to-one connection between first engagement features and second engagement features. Optionally, the interface portion may comprise a cylindrical interface surface. For example, the plurality of second engagement features may be spaced about the circumference of the cylindrical interface surface. Optionally, the second engagement feature may comprise a first portion configured (e.g., shaped, located) to engage the first engagement feature, and a second portion configured (e.g., shaped, located) to engage the guiding channel. In certain embodiments, the first portion and the second portion may be portions of a single radial protrusion from the interface portion. In other embodiments, the first portion and the second portion may comprise independent radial protrusions from the interface portion. Optionally, the actuator may comprise an outwardly directed protrusion which is operable by a user to move the actuator from the locking position to the open position for uncoupling the interface portion from the actuator. This may help improve the ease of use of the attachment mechanism. The invention includes the combination of the aspects and optional features described except where such a combination is clearly impermissible or expressly avoided. BRIEF DESCRIPTION OF THE DRAWINGS Figures 1(a) and 1(b) show perspective views of a main body of a haircare appliance which may be used in embodiments of the present invention; Figure 2 shows an exploded view of an attachment mechanism according to an embodiment of the present invention; Figure 3 shows a cross-sectional view of the attachment mechanism of Fig. 2 with an interface portion coupled to an actuator; Figure 4 shows a top-down view of the attachment mechanism of Fig. 2; Figure 5 shows a cross-section view of an attachment mechanism which is another embodiment of the present invention; Figure 6 shows a top view of an actuator which may be used in further embodiments of the present invention; Figure 7 shows an exploded view of an attachment mechanism according to a third embodiment of the present invention; Figure 8 shows a cross-sectional view of the attachment mechanism of Fig. 7 with an interface portion coupled to an actuator; Figure 9 shows a cross-section view of an attachment mechanism according to a fourth embodiment of the present invention; Figure 10 shows an exploded view of the attachment mechanism of Fig. 9; Figure 11 shows an additional cross-section view of the attachment mechanism of Fig. 9; Figure 12 shows a cross-section view of an attachment mechanism according to a fifth embodiment of the present invention; and Figures 13(a) and 13(b) show cross-section views of an outer collar which may be used in embodiments of the present invention. DETAILED DESCRIPTION Figs. 1(a) and 1(b) show perspective views of a main body 1000 of a haircare appliance which may be used in embodiments of the present invention. The main body 1000 comprises an outer wall 1005 which functions as a handle for the haircare appliance, and which has a fluid inlet 1015 at a first end 1010 and a fluid outlet 1025 at a second end 1020, with a fluid flow path through the main body 1000 from the fluid inlet 1015 to the fluid outlet 1025. The outer wall 1005 defines an elongate tubular structure for the main body 1000, wherein the cross-sectional shape of the main body 1005 perpendicular to the longitudinal axis of the main body is elliptical or oval such that the main body 1000 is ergonomically designed to be comfortable for a user to hold. The main body 1005 houses a motor which is configured to generate a flow of fluid (in particular, air) along the fluid flow path. The fluid is optionally heated by a heater (not shown) before exiting the main body 1000 at the fluid outlet 1025. The main body 1000 is connectable to a power supply via a power cable 1030 which extends from the first end 1010 of the main body 1000. However, in some embodiments, the main body 1000 may further house one or more batteries such that the power cable 1030 may not be required. The main body comprises a user interface which may include control settings for the haircare appliance. In this embodiment, the user interface is split, with a first portion of the user interface 1040a being positioned towards a first end 1010 of the main body 1000, and a second portion of the user interface 1040b being positioned towards a second end 1020 of the main body 1000. However, it will be understood that, in other embodiments, the user interface may be generally positioned at a single location on the main body 1000. The main body 1000 is configured to allow an attachment to be removably connected thereto, by comprising at least a portion of an attachment mechanism at or about the second end 1020 of the main body 1000. The attachment mechanism is described in more detail below. The attachment mechanism enables a user to create different hair styles and gives the haircare appliance additional functionality, by allowing the attachment to be removed and replaced with an alternative attachment. An attachment mechanism 100 according to an embodiment of the present invention is described below with respect to Figs. 2-4, wherein Fig. 2 shows an exploded view of the attachment mechanism 100; Fig. 3 shows a cross-sectional view of the attachment mechanism 100 with an interface portion 120 coupled to an actuator 110; and Fig. 4 shows a top-down view of the attachment mechanism 100. Common reference numerals are used in each figure to designate corresponding features. The attachment mechanism 100 may be used for removably connecting an attachment for a haircare appliance with a main body of the haircare appliance. For example, the haircare appliance may be a haircare appliance 1000 as described above with respect to Figs. 1(a) and 1(b). The attachment mechanism 100 comprises an actuator 110 and an interface portion 120, wherein the interface portion 120 is removably couplable to the actuator 110. In this embodiment, the interface portion 120 may form part of an attachment and the actuator 110 may be mounted on the main body (either directly or indirectly, as described herein) such that, by coupling the interface portion 120 to the actuator 110, the attachment may be removably connected to a main body. However, it will be understood that, in other examples of the present invention, an interface portion may form part of the main body of the haircare appliance and an actuator may be mounted on the attachment. As described above with respect to Fig. 1, at least a portion of an attachment mechanism such as the attachment mechanism 100 shown in Fig. 2 is generally located at or about the second end 1020 of the main body 1000. In this description, it will be understood that a direction which is generally from the actuator towards the interface portion is referred to as a ‘upper’ or ‘upward’ direction. The opposite direction, i.e., generally from the interface portion towards the actuator, is referred to herein as a Tower’ or ‘downward’ direction. For completeness, it is also noted that ‘inner’ or ‘inwards’ refers to a direction towards the longitudinal axis of the haircare appliance, attachment mechanism and components thereof, and ‘outer’ or ‘outwards’ refers to a direction away from the longitudinal axis of attachment mechanism, the haircare appliance, and components thereof. The actuator 110 is an annular structure, generally in the form of a short cylinder. The actuator 110 comprises a plurality of protrusions on its inner surface for engaging corresponding protrusions on an outer surface of the interface portion 120. In particular, the actuator 110 comprises a plurality of first engagement features 112, which each have the form of a wedge-shaped protrusion from the inner surface of the actuator 110. Although not shown, the actuator 110 comprises four first engagement features 112 which are spaced about the circumference of the actuator 110. In particular, the four first engagement features 112 may be spaced about the circumference of the actuator 110 such that the first engagement features 112 have rotational symmetry about the longitudinal axis of the actuator 110. This may enable the interface portion 120 to be connected to the actuator in a plurality of different orientations, and a plurality of first engagement features 112 may also strengthen the connection between the actuator 110 and the interface portion 120. It will be appreciated that in other examples different numbers of first engagement features may be present 112. Each wedge-shaped protrusion has a lower surface, which is referred to herein as a first engagement surface 111 (which may be referred to as a first surface of the protrusion), and an upper surface 114 (which may be referred to as a second surface of the protrusion). The first engagement surface 111 and the upper surface 114 are angled relative to one another, and angled relative to the plane of the actuator 110, which helps facilitate operation of the attachment mechanism 100 in a manner described in more detail below. The actuator 110 is slidably mounted on a bearing surface 130, the bearing surface 130 being mounted or connected to the main body of the haircare appliance. However, it will be appreciated that in other embodiments of the attachment mechanism 100 the bearing surface 130 may be mounted or connected to the attachment of the haircare appliance. The actuator 110 is rotatable on the bearing surface 130 between an open position, in which the interface portion 120 can be easily uncoupled from the actuator 110, and a locking position (which may also be referred to herein as a closed position), in which the interface portion 120 is coupled to the actuator 110. The bearing surface 130 thereby ensures the actuator 110 is able to move between open and locking positions without becoming misaligned or moving out of position relative to the other parts of the attachment mechanism 100. As the actuator 110 is an annular structure which is rotatable about the longitudinal axis of the locking mechanism, the length of a haircare appliance to which the attachment mechanism 100 is applied may be reduced due to the decreased longitudinal space required for the attachment mechanism 100. In contrast, known devices require parts of an attachment mechanism to be slidable in a longitudinal direction which leads to an increased length of the haircare appliance. The bearing surface 130 has a plurality of ridges 132 which are arranged to abut a lower face of the actuator 110. By reducing the contact area between the actuator 110 and the bearing surface 130, the plurality of ridges 132 reduce friction between these components, allowing the actuator 110 to move more easily between the open and locking positions. In some embodiments, the attachment mechanism 100 may comprise a seal which is applied to the bearing surface 130. In such arrangements, it will be appreciated that the seal (in particular, an upper face thereof), will provide a bearing surface, upon which the actuator is slidable for example. In order to correctly position the actuator 110 relative to the bearing surface 130, the actuator 110 comprises a plurality of downwardly directed protrusions 116 which are configured to fit with the bearing surface 130. This may help to ensure that the actuator 110 is correctly aligned with respect to the other components of the attachment mechanism 100. To ensure correct positioning of the actuator 110, as well as provide a limited range of movement which defines the open position and the locking position, the bearing surface 130 comprises one or more channels 131a, 13 lb at or about an outer edge thereof, wherein each channel 131a, 131b is configured to receive a downwardly directed protrusion 116. The arc length of the channel 131a, 131b defines the angular distance over which the actuator 110 is able to rotate. For example, when a downwardly directed protrusion 116 abuts a first end of a channel 131a, 13 lb the actuator 110 is in the open position, and when the downwardly directed protrusion 116 abuts a second end of the channel 131a, 13 lb the actuator 110 is in the locking position. Also protruding from a lower edge of the actuator 110 is a first spring engagement portion 117, which is configured to fit with one end of a spring 150. The other end of the spring 150 is received by a second spring engagement portion 133, which is an outwardly directed protrusion from the bearing surface 130. By providing the spring 150 between the actuator 110 and the bearing surface 130 in this way, the actuator 110 is biased towards the locking position. Of course, it will be appreciated that in other embodiments of the invention, any other suitable means of biasing the actuator 110 towards the locking position may be considered. In addition to the first engagement feature 112, the actuator 110 also comprises at least one locating protrusion 118 on an inner surface, which may help to ensure that the interface portion 120 is kept in alignment with the actuator 110 when the interface portion 120 is coupled to the actuator 110. The locating protrusion 118 also helps to define a limit of rotation of the actuator 110, in a similar manner as the channels 131a, 13 lb in the bearing surface 130. In particular, lateral edges of the locating protrusion 118 may abut protrusions from the interface portion 120 in one or both of the locking position and open position of the actuator 110, thereby limiting rotational movement of the actuator 110 relative to the interface portion 120. In order to allow a user to operate the actuator 110, and so move the actuator from the locking position to the open position, the actuator 110 comprises an outwardly directed protrusion 113 which is operable by a user. In this embodiment, the outwardly directed protrusion 113 comprises a separate component which is fitted into an aperture 115 in the actuator. This may allow the outwardly directed protrusion 113 to be made of a material which is more visually or haptically pleasing for a user compared with the material comprising the actuator 110, as the outwardly directed protrusion 113 is visible and contactable by a user, whereas the remainder of the actuator 110 is generally positioned within an outer collar 140 connected to the main body (or, in some embodiments, connected to the attachment) and so is not visible or contactable by a user. Of course, it will be appreciated that in other embodiments, the outwardly directed protrusion 113 may be made of the same material as the actuator 110, and / or the protrusion 113 and the actuator 110 may be a unitary component. The interface portion 120 comprises a cylindrical interface surface 123 which is configured to be received within or through the aperture through the annular actuator 110 when the interface portion is coupled thereto. In this embodiment, the cylindrical interface surface 123 extends downwardly from a lower or proximal end of an attachment for a haircare appliance, but it will be appreciated that in other examples the interface portion 120 may instead be part of the main body, such that the cylindrical interface surface 123 may extend upwardly from a second end of the main body, for example. It may also be considered that the actuator 110 may be received within the interface surface 123 in certain embodiments. The interface portion 120 comprises plurality of radial protrusions extending outwardly from the cylindrical interface surface for engaging corresponding protrusions on an inner surface of the actuator 110. In particular, the interface portion comprises a plurality of second engagement features, which each interact with a corresponding first engagement feature 112 of the actuator 110 as described in more detail below. Each second engagement feature is formed by one or more protrusions which extend generally between the top and bottom edges of the cylindrical interface surface 123, and the second engagement feature is configured to interact with the first engagement feature 112 such that the interface portion 120 may be coupled or locked to the actuator 110 for connecting an attachment to a main body. In other embodiments, it will be appreciated that the second engagement feature may be provided as a recess (e.g., in the form of a groove or the like) in the cylindrical interface surface 123. In the embodiment shown in Figs. 2-4, each second engagement features comprises a first portion 122a, and a second portion 122b which is vertically spaced from the first portion 122a. The vertical spacing of the first portion 122a from the second portion 122b allows the second engagement feature to interact with the first engagement feature 112 to couple the interface portion 120 with the actuator 110 as described herein. The first portion 122a and the second portion 122b are, in this example, independent radial protrusions from the cylindrical interface surface 13. In other embodiments it is envisaged that the first portion 122a and the second portion 122b of the second engagement feature may be formed as a single protrusion, for example with a web portion joining the first portion 122a and the second portion 122b. Although not shown, the interface portion 120 comprises four second engagement features which are spaced about the circumference of the cylindrical interface surface 123. In particular, the four second engagement features may be spaced about the circumference of the interface surface 123 such that the second engagement features have rotational symmetry about the longitudinal axis of the interface portion 120. This may enable the interface portion 120 to be connected to the actuator 110 in a plurality of different orientations. It will be appreciated that in other examples different numbers of first engagement features may be present 112. For example, the number of second engagement features may correspond to the number of first engagement features 112 which are provided in order to provide a secure connection between the interface portion 120 and the actuator 110. As the interface portion 120 is moved downwards into contact with the actuator 110 for coupling therewith, the first portion 122a of the second engagement feature engages the upper surface 114 of the first engagement feature 112 and, as the upper surface 114 of the first engagement feature 112 is at an angle relative to the plane of the actuator 110, the actuator 110 is moved laterally towards the open position. This allows the interface portion 120 to be coupled to the actuator 110 by a ‘push-to-lock’ mechanism, such that an attachment can be connected to a main body without requiring a user to manually rotate either of the actuator 110 or the interface portion 120. The lower face of the first portion 122a is rounded to reduce the contact area, and so reduce friction, between the first portion 122a of the second engagement feature and the upper surface 114 of the first engagement feature. The second engagement feature comprises a second engagement surface 121 which, in this embodiment, is an upper surface of the first portion 122a of the second engagement feature. The second engagement surface 121 is angled relative to the first engagement surface 111 such that, when the interface portion 120 is coupled with the actuator 110, the first engagement surface 111 and the second engagement surface 121 are mutually engaged to prevent the interface portion 120 being uncoupled from the actuator 110 (i.e., preventing upward movement of the interface portion 120), and such that the biasing force from the spring 150 provides a reaction force between the first engagement surface 111 and the second engagement surface 121 which acts to pull the actuator 110 and the interface portion 120 towards one another. In some embodiments, when the interface portion 120 is coupled with the actuator 110, a lower surface of the second portion 122b of the second engagement feature may be engaged with the upper surface 114 of the first engagement feature 112. In this way, the first engagement feature 112 may be held between the first portion 122a and the second portion 122b of the second engagement feature, ensuring that the interface portion 120 is securely coupled with the actuator 110, and, when the actuator 110 is in the locking position, the interface portion 120 is not able to move in either an upward or a downward direction. Furthermore, when the interface portion 120 is coupled with the actuator 110, the lower face of the first portion 122a may be in contact with the bearing surface 130, further limiting movement of the interface portion 120 relative to the actuator 110. The interface portion 120 further comprises one or more locating features 124. Each locating feature 124 comprises a generally rectangular protrusion from the cylindrical interface surface 123 which extends between the top and bottom edges of the interface surface 123. The locating feature 124 is configured such that when the interface portion 120 is coupled to the actuator, a lower face of the locating feature 124 is in contact with the bearing surface 130, to ensure that the interface portion 120 is correctly located in the longitudinal direction with respect to the actuator. The attachment mechanism 100 additionally comprises an outer collar 140, which is arranged to house the actuator 110 and the bearing surface 130, and to receive the interface portion 120 when the interface portion 120 is moved into contact with, and couples to, the actuator 110. Fig. 4 shows a top-down view of the attachment mechanism 100, which shows that the outer collar 140 has an elliptical cross-sectional shape perpendicular to its longitudinal axis. The shape of the outer collar 140 is configured to correspond with the cross-section shape of a main body of the haircare appliance, e.g., by having the same dimensions as the outer wall of the main body. In particular, when the outer collar 140 is connected to a main body, the outer collar 140 provides a continuation of the outer wall of the main body to provide a consistent appearance. The outer collar 140 has a lip 144 depending from a lower surface thereof for connecting the outer collar 140 to the main body of a haircare appliance. The outer collar 140 also comprises an aperture 143 through a sidewall thereof through which the outwardly directed protrusion 113 of the actuator 110 may protrude in order to be operable by a user. The upper end surface of the outer collar 140 comprises a circular opening for receiving the interface portion 120, in particular for receiving the cylindrical interface surface 123. In order to ensure that the interface portion 120 is correctly aligned relative to the actuator 110 for coupling, the outer collar 140 comprises an inwardly directed flange 145 on an inner surface thereof at or about the circular opening. The flange 145 comprises a plurality of guiding channels 141 which are configured (e.g., configured by way of their positioning and sizing) to receive the second engagement features, which slide through the guiding channels when the interface portion 120 is moved into contact with the actuator 110. The guiding channels 141 are positioned to guide the second engagement features into contact with the first engagement features 112, thereby helping the attachment mechanism 100 to operate as a ‘push-to-lock’ mechanism where the user simply needs to push the interface portion 120 towards the actuator 110 in a longitudinal direction, and is not required to rotate either part when coupling the actuator 100 and the interface portion 120 (for example, as would be the case with a conventional bayonet fitting where a bayonet protrusion is fitted within an angled groove or slot). The guiding channels 141 facilitate this operation by ensuring that the second engagement features are correctly aligned with the first engagement features 112 when the user moves the interface portion 120 in the longitudinal direction. Similarly, the inwardly directed flange comprises a plurality of locating channels 142, through which the locating features 124 are configured to slide when the interface portion 120 is moved into contact with the actuator 110. The locating channels 142 therefore provide similar advantages as the guiding channels 141, by helping to ensure that the second engagement features are correctly aligned with the first engagement features 112 when the user moves the interface portion 120 in the longitudinal direction. Furthermore, when the interface portion 120 is coupled to the actuator 110, a second portion 122b of the second engagement feature is at last partially positioned within the guiding channel 141, such that the interface portion 120 has a fixed rotational position relative to the locking position of the actuator 110. Similarly, each locating feature 124 is at least partially positioned within a locating channel 142 when the interface portion 120 is coupled to the actuator 110. As can be seen in Fig. 4, the attachment mechanism 100 comprises four guiding channels 141 in the flange 145 of the outer collar 140. Likewise, the attachment mechanism 100 comprises four first engagement features 112 and four second engagement features, wherein each second engagement feature is arranged to slide through a respective guiding channel 141 in order to interact with a respect first engagement feature 112. By providing a plurality of first and second engagement features in this way, the attachment mechanism 100 provides a secure and stable connecting between the interface portion 120 and the actuator 110. Of course, it will be appreciated that in other embodiments any suitable number of first and second engagement features may be provided, and the number of first engagement features may not need to be equal to the number of second engagement features. Fig. 4 shows that the cross-sectional shape of the outer collar 140 has a major axis 146, which also corresponds with a major axis of a main body for which the attachment mechanism 100 is configured. In this embodiment, each guiding channel 141 is located at a position which is circumferentially spaced from the major axis by 30° (and, therefore, closer to the major axis than a minor axis), as shown by angle 147. It will be appreciated that the first engagement features 112 and the second engagement features are also similarly spaced about the circumference of the actuator 110 and the interface surface 123. That is, four first engagement features 112 are arranged in two pairs wherein within each pair the first engagement features 112 are spaced about by 60°, and the two pairs are diametrically opposed to one another across the actuator 110. In this embodiment, the locating channels 142 are arranged to diametrically oppose each across the major axis of the outer collar 140, such that they are positioned 180° apart from one another. Such an arrangement helps to correctly align a main body and an attachment of a haircare appliance when they are connected by a user, as well as ensuring that the main body and the attachment are stably connected by positioning the connection points closer to the axis along which the attachment is likely to tilt relative to the main body. The arrangement also provides two-fold rotational symmetry of the attachment mechanism 100, allowing the interface portion 120 to be coupled to the actuator 110 in either of two orientations, improving ergonomics of the attachment mechanism 100 and the haircare appliance. In other embodiments, the guiding channels 141 may be equally spaced about the circumference of the flange 145, with corresponding placement of the first engagement features 112 and second engagement features, for example, or may have any other suitable distribution. An upper surface of the flange 145 is arranged to abut a corresponding rim 125 which extends outwardly from an upper edge of the interface surface 123 when the interface portion 120 is coupled to the actuator 110. In particular, the upper surface of the flange 145 is chamfered to fit with a corresponding chamfer on a lower edge of the rim 125 to help align the longitudinal axis of the interface portion 120 with a longitudinal axis of the actuator 110. Fig. 3 shows a cross-sectional view of the locking mechanism 100 wherein the interface portion 120 is coupled to the actuator 110. In particular, Fig. 3 shows the actuator 110 in the locking position such that the interface portion 120 is securely coupled to the actuator 110 and cannot be accidentally removed or displaced. As shown in Fig. 3, when the interface portion 120 is coupled to the actuator 110, the actuator 110 is biased towards the locking position by the spring 150 such that the first engagement feature 112 and the second engagement feature are mutually engaged to prevent the interface portion 120 being uncoupled from the actuator 110. In particular, the first engagement surface 111 and the second engagement surface 121 are mutually engaged, and it can be seen that the second engagement surface 121 is angled relative to the first engagement surface 111 such that the biasing force provided by the spring 150 (which acts to bias the first engagement feature 112 towards the second engagement feature in a lateral direction, i.e., from left to right as seen in Fig. 3) provides a reaction force between the first engagement surface 111 and the second engagement surface 121 which acts to pull the actuator 110 and the interface portion 120 towards one another (that is, the interface portion 120 is generally pulled downwards as shown in Fig. 3). In contrast, if the second engagement surface 121 were parallel with the first engagement surface 111, the surfaces would simply slide over one another, and so the biasing force provided by the spring 150 would not provide such a reaction force. Fig. 3 also shows that a second portion 122b of the second engagement feature is at least partially positioned within the guiding channel 141, such that the interface portion 120 is held in a fixed rotational position relative to the locking position of the actuator 110. A lower surface of the first portion 122a of the second engagement feature is in contact with the bearing surface 130, limiting the movement of the interface portion 120 in the longitudinal direction. Fig. 5 shows a cross-sectional view of a second attachment mechanism 200 according to another embodiment of the present invention, wherein an interface portion is coupled to an actuator. In particular, Fig. 5 shows the actuator in the locking position such that the interface portion is securely coupled to the actuator and cannot be accidentally removed or displaced. Where features of the second locking mechanism 200 are generally the same as the locking mechanism 100 described above with respect to Figs. 2-4, the same reference numerals are used. In this embodiment, the second engagement feature comprises a single protrusion from a cylindrical interface surface. That is, the second engagement feature comprises a first portion 222a and a second portion 222b which are joined by a web portion 226, wherein the first portion 222a is arranged to interact with the first engagement feature 112, and the second portion 222b is vertically spaced from the first portion 222a. When the interface portion is coupled to the actuator, the actuator is biased towards the locking position (e.g., by a spring) such that the first engagement feature 112 and the second engagement feature are mutually engaged to prevent the interface portion being uncoupled from the actuator. In particular, the first engagement surface 111 and the second engagement surface 121 (an upper surface of the first portion 222a) are mutually engaged, and it can be seen that the second engagement surface 121 is angled relative to the first engagement surface 111 such that the biasing force (which acts to bias the first engagement feature 112 towards the second engagement feature in a lateral direction, i.e., from left to right as seen in Fig. 5) provides a reaction force between the first engagement surface 111 and the second engagement surface 121 which acts to pull the actuator and the interface portion towards one another (that is, the interface portion is generally pulled downwards as shown in Fig. 5). In contrast, if the second engagement surface 121 were parallel with the first engagement surface 111, the surfaces would simply slide over one another, and so the biasing force would not provide such a reaction force. Fig. 5 also shows that the second portion 222b of the second engagement feature is at least partially positioned within the guiding channel 141, such that the interface portion is held in a fixed rotational position relative to the locking position of the actuator. In this embodiment of the attachment mechanism, about the entrance to the guiding channel 141, the flange comprises sloped surfaces 246 which are sloped downwardly towards the guiding channel 241. This may help a user locate the second interface feature within the guiding channel 241 when coupling the interface portion with the actuator. An upper portion of the second engagement portion is shaped to abut the sloped surfaces 246, and so help prevent lateral or rotational movement of the interface portion when coupled to the actuator. Fig. 6 shows a top view of an alternative actuator 210 which may be used in embodiments of the present invention. This example comprises four first engagement features 212 which are evenly spaced about the circumference of the actuator. That is, each first engagement feature 212 is positioned 90° away from the next engagement feature 212. It will be appreciated that the actuator 210 may be used in an embodiment of the attachment mechanism wherein second engagement features of an interface portion are similarly spaced about the circumference of the interface surface, and guiding channels are similarly spaced on the outer collar. Such an arrangement may provide four-fold symmetry of the attachment mechanism, which may allow the interface portion to be coupled to the actuator 210 in any of four orientations, improving ergonomics of the attachment mechanism and the haircare appliance. Of course, it will be appreciated that the actuator 210 may be used in embodiments where the interface portion has other numbers of second engagement features, such as 1, 2 or 3 engagement features, which are each positioned on the interface surface so as to fit with a first engagement feature 210. A third attachment mechanism 300 which is a further embodiment of the present invention will now be described with reference to Fig. 7 and Fig. 8, wherein Fig. 7 shows an exploded view of the attachment mechanism 300 and Fig. 8 shows a cross-sectional view of the attachment mechanism 300. Where features of the third attachment mechanism 300 are the same as features described previously (e.g., with respect to the first attachment mechanism 100), corresponding reference numerals are used and description thereof is not repeated. The attachment mechanism 300 comprises an actuator 310 and an interface portion 320, wherein the interface portion 320 is removably couplable to the actuator 310. In this embodiment, the interface portion 320 may form part of an attachment and the actuator 310 may be mounted on the main body (either directly on indirectly, as described herein) such that, by coupling the interface portion 320 to the actuator 310, the attachment may be removably connected to a main body. However, it will be understood that, in other examples of the present invention, an interface portion may form part of the main body of the haircare appliance and an actuator may be mounted on the attachment. The actuator 310 is an annular structure, generally in the form of a short cylinder. The actuator 310 comprises a plurality of protrusions on its inner surface for engaging recesses in an outer surface of the interface portion 320. In particular, the actuator 310 comprises a plurality of first engagement features 312, which are each generally hemispherical radial protrusions. Although not shown, the actuator 310 comprises four first engagement features 312 which are spaced about the circumference of the actuator 310. In particular, the four first engagement features 312 may be spaced about the circumference of the actuator 310 such that the first engagement features 312 have rotational symmetry about the longitudinal axis of the actuator 310 (e.g., by being spaced 90° apart from one another about the circumference of the actuator 310). This may enable the interface portion 320 to be connected to the actuator in a plurality of different orientations, and a plurality of first engagement features 312 may also strengthen the connection between the actuator 310 and the interface portion 320. It will be appreciated that in other examples different numbers of first engagement features may be present 312. Each first engagement feature 312 has a lower surface (or a first surface), which is referred to herein as a first engagement surface 311, and an upper surface 314 (or a second surface). The upper surface 314 is a curved surface, and the first engagement surface 311 is angled relative to the plane of the actuator 310, which helps facilitate operation of the attachment mechanism 300 as described in more detail below. The actuator 310 is slidably mounted on a bearing surface 330, which in this embodiment is an upper surface of a seal 360 which fits between the actuator 310 and the main body of the haircare appliance. The seal 360 may help ensure that fluid passing through the hairstyling appliance exits the appliance only at the intended fluid outlets. It will be appreciated that in other embodiments of the attachment mechanism 100 a bearing surface 330 may be mounted or connected to the attachment of the haircare appliance. The actuator 310 is rotatable on the bearing surface 330 between an open position, in which the interface portion 320 can be easily uncoupled from the actuator 310, and a locking position, in which the interface portion 320 is coupled to the actuator 310. The bearing surface 330 thereby ensures the actuator 310 is able to move between open and locking positions without becoming misaligned or moving out of position relative to the other parts of the attachment mechanism 300. As the actuator 310 is an annular structure which is rotatable about the longitudinal axis of the locking mechanism, the length of a haircare appliance to which the attachment mechanism 300 is applied may be reduced due to the decreased longitudinal space required for the attachment mechanism 300. In contrast, known devices require parts of an attachment mechanism to be slidable in a longitudinal direction which leads to an increased length of the haircare appliance. Protruding from a lower edge of the actuator 3110 is a first spring engagement portion 317, which is configured to fit with one end of a spring 150. The other end of the spring 150 is received by a second spring engagement portion 333, which is an outwardly directed protrusion from a main body. By providing the spring 150 between the actuator 310 and the main body in this way, the actuator 310 is biased towards the locking position. Of course, it will be appreciated that in other embodiments of the invention, any other suitable means of biasing the actuator 310 towards the locking position may be considered. In order to keep the actuator 310 in position and in alignment on the main body, the main body comprises a cylindrical protrusion 1026 extending longitudinally from a second end thereof, and the actuator 310 is configured to fitted coaxially around the outer surface of the protrusion 1026. In order to allow a user to operate the actuator 310, and so move the actuator from the locking position to the open position, the actuator 310 comprises an outwardly directed protrusion 313 which is operable by a user. In this embodiment, the outwardly directed protrusion 313 is made of the same material as the actuator 310, and the protrusion 313 and the actuator 310 are formed as a unitary component. The interface portion 320 comprises a cylindrical interface surface 323 which is configured to be received within or through the aperture through the annular actuator 310 when the interface portion is coupled thereto. In this embodiment, the cylindrical interface surface 323 extends downwardly from a lower or proximal end of an attachment for a haircare appliance, and an inner surface of the interface portion 320 may overlie the outer surface of the cylindrical protrusion 1026 of the main body. It will be appreciated that in other examples the interface portion 320 may instead be part of the main body, such that the cylindrical interface surface 323 may extend upwardly from a second end of the main body, for example. It may also be considered that the actuator 310 may be received within the interface surface 323 in certain embodiments. The interface portion 320 comprises a plurality of second engagement features 322 in the form of recesses or grooves into the cylindrical interface surface 323, such that each second engagement feature 322 is configured to receive a corresponding first engagement feature 312 when the interface portion 320 is coupled to the actuator 310. Although not shown, the interface portion 320 comprises four second engagement features which are spaced about the circumference of the cylindrical interface surface 323. In particular, the four second engagement features may be spaced about the circumference of the interface surface 323 such that the second engagement features have rotational symmetry about the longitudinal axis of the interface portion 320 (e.g., by being spaced apart by 90° about the circumference of the interface surface 323). This may enable the interface portion 320 to be connected to the actuator 310 in a plurality of different orientations. It will be appreciated that in other examples different numbers of first engagement features may be present 312. For example, the number of second engagement features 322 may correspond to the number of first engagement features 312 which are provided in order to provide a secure connection between the interface portion 320 and the actuator 310. The second engagement feature 322 comprises a recess or groove into the cylindrical interface surface 323, the groove generally extending along the interface surface 323 in a direction which is parallel with the longitudinal axis of the interface portion 320. A sidewall of the groove has a circumferential or lateral projecting portion 327 which gradually narrows or constricts the width of the groove in the upwards direction, forming a general triangular or wedge shape. An upper surface of the projection portion 327 provides a second engagement surface 321, and a lower surface of the projection portion 327 provides a guiding surface 328. As the interface portion 320 is moved downwards and into contact with the actuator 310 for coupling therewith, the first engagement feature 312 engages the second engagement feature 322. In particular, an upper surface 314 of the first engagement feature 312 engages the guiding surface 328. As the guiding surface 328 is angled relative to the plane of the actuator 310, and the upper surface 314 of the first engagement feature 312 is curved, the downward motion of the interface portion 320 acts to move the actuator 310 laterally from the locking position towards the open position. This allows the interface portion 320 to be coupled to the actuator 310 by a ‘push-to-lock’ mechanism, such that an attachment can be connected to a main body with requiring a user to manually rotate either of the actuator 310 or the interface portion 320. The curved upper surface 314 of the first engagement feature 312 reduces the contact area, and so reduces friction, between the first engagement feature 312 and the second engagement feature 322. The second engagement surface 321 is also angled relative to the plane of the actuator 310, and relative to the first engagement surface 311, such that, when the interface portion 320 is coupled with the actuator 310, the first engagement surface 311 and the second engagement surface 321 are mutually engaged to prevent the interface portion 320 being uncoupled from the actuator 310 (i.e., preventing upward movement of the interface portion 320), and such that the biasing force from the spring 150 provides a reaction force between the first engagement surface 311 and the second engagement surface 321 which acts to pull the actuator 310 and the interface portion 320 towards one another. When the interface portion 320 is coupled with the actuator 310, a lower end face of the cylindrical interface surface 323 may be in contact with the bearing surface 330, limiting movement of the interface portion 320 relative to the actuator 310. The attachment mechanism 300 additionally comprises an outer collar 340, which is arranged to house the actuator 310 and the bearing surface 330, and to receive the interface portion 320 when the interface portion 320 is moved into contact with, and couples to, the actuator 310. The shape of the outer collar 340 may be configured to correspond with the cross-section shape of a main body of the haircare appliance, e.g., by having the same dimensions as the outer wall of the main body. For example, when the outer collar 340 is connected to a main body, the outer collar 340 provides a continuation of the outer wall of the main body to provide a consistent appearance. The outer collar 340 also comprises an aperture 343 through a sidewall thereof through which the outwardly directed protrusion 313 of the actuator 310 may protrude in order to be operable by a user. The upper end surface of the outer collar 340 comprises a circular opening for receiving the interface portion 320, in particular for receiving the cylindrical interface surface 323. In order to ensure that the interface portion 320 is correctly aligned relative to the actuator 310 for coupling, the outer collar 340 comprises an inwardly directed flange 345 on an inner surface thereof at or about the circular opening. This may help to ensure that the longitudinal axis of the interface portion 320 is aligned with the longitudinal axis of the other elements of the attachment mechanism 300 when the user moves the interface portion 320 in the longitudinal direction. A fourth attachment mechanism 400 which is a further embodiment of the present invention will now be described with reference to Figs. 9 to 11, wherein Fig. 9 shows a cross-section view of the attachment mechanism 400, Fig. 10 shows an exploded view of the attachment mechanism 400, and Fig. 11 shows an additional cross-section view of the attachment mechanism 400. Where features of the fourth attachment mechanism 400 are the same as features described previously (e.g., with respect to the first attachment mechanism 100), corresponding reference numerals are used and description thereof is not repeated. The attachment mechanism 400 comprises an actuator 410 and an interface portion 420, wherein the interface portion 420 is removably couplable to the actuator 410. In this embodiment, the interface portion 420 may form part of an attachment and the actuator 410 may be mounted on the main body (either directly or indirectly) such that, by coupling the interface portion 420 to the actuator 410, the attachment may be removably connected to the main body. However, it will be understood that, in other examples of the present invention, an interface portion may form part of the main body of the haircare appliance and an actuator may be mounted on the attachment. Generally, the fourth attachment mechanism 400 is the same as the first attachment mechanism 100 described above. However, the fourth attachment mechanism 400 differs in the arrangement of the first and second interface surfaces, and by further comprising a resiliently deformable seal 460. The configuration and effect of these features is described below. In this embodiment, the actuator 410 comprises a plurality of first engagement features 412, which are wedge-shaped protrusions. Each of the wedge-shaped protrusions comprises an upper surface 114 substantially as the first attachment mechanism 100. However, in this attachment mechanism 400, the first engagement surface 411 is parallel with the plane of rotation of the actuator 410, and is not at an angle tothe plane of rotation of the actuator 410 as in the first attachment mechanism 100 described above. Correspondingly, the second engagement surface 421, which is a surface of a first portion 422a of a second engagement feature located on the interface portion 420, is parallel to the first engagement surface 411. As the actuator 410 moves towards the locking position (by rotating on the bearing surface 130), the first engagement surface 411 and the second engagement surface 421 slide past one another. When the actuator 410 is in the locking position, as shown in Fig. 9, the first engagement surface 411 and the second engagement surface 421 oppose one another. In order to ensure that the first engagement surface 411 and the second engagement surface 421 are mutually engaged in order to stabilise the connection between the actuator 410 and the interface portion 420, the attachment mechanism 400 comprises a resiliently deformable seal 460. A cross-section of the seal 460 is shown in Fig. 11. The resiliently deformable seal 460 is located between a bottom surface of the interface portion 420 and the bearing surface 130 when the interface portion 420 is connected to the actuator 410, and is thereby compressed. However, as the seal 460 is resiliently deformable, the seal 460 applies a biasing force to the interface portion 420 and thereby biases the second engagement surface 421 towards the first engagement surface 411, such that the first engagement surface 411 and the second engagement surface 421 are mutually engaged, preventing the interface portion 420 being removed from the actuator 410. The resiliently deformable seal 460 is made of an elastic material, in particular a silicone rubber material, such that the material of the seal 460 itself contributes to the resilient deformability of the seal 460. Furthermore, as shown in Fig. 11, the resiliently deformable seal 460 comprises a body portion 462 and a protruding flange 464, wherein the flange 464 is angled relative to the body portion 462. In particular, the flange 464 extends upwardly away from the body portion 462 at an angle of around 45°. As a result of this arrangement, the shape of the resiliently deformable seal 460 itself contributes to the manner in which the resiliently deformable seal 460 applies a biasing force to the interface portion 420, further strengthening a connection between the actuator 410 and the interface portion 420, for example to help ensure that an attachment is securely attached to a main body. The second engagement surface 421 comprises a ramped portion 421a which is angled relative to the remainder of the second engagement surface 421. As shown in Fig. 9, this ramped portion 421a is positioned at a leading edge of the second engagement surface 421, i.e., at an end of the second engagement surface 421 which first interacts with or opposes the first engagement surface 411 when the actuator 410 moves towards the locking position. By providing a ramped portion 421a in this way, it can be ensured that the first engagement feature 412 is correctly aligned with and passes over the second engagement feature such that the first engagement surface 411 and the second engagement surface 421 slide past one another as the actuator 410 moves towards the locking position. Fig. 12 shows a cross-section view of a fifth attachment mechanism 500 which is a further embodiment of the present invention. Where features of the fourth attachment mechanism 500 are the same as features described previously (e.g., with respect to the first attachment mechanism 100), corresponding reference numerals are used and description thereof is not repeated. As in previously described embodiments, the attachment mechanism 500 comprises an actuator and an interface portion, wherein the interface portion is removably couplable to the actuator. In this embodiment, the interface portion may form part of an attachment and the actuator may be mounted on the main body (either directly or indirectly) such that, by coupling the interface portion to the actuator, the attachment may be removably connected to the main body. However, it will be understood that, in other examples of the present invention, an interface portion may form part of the main body of the haircare appliance and an actuator may be mounted on the attachment. Generally, the fifth attachment mechanism 500 is the same as the fourth attachment mechanism 400 described above. However, the fifth attachment mechanism 500 differs in the arrangement of the first and second interface surfaces. In this embodiment, each first engagement feature 512 is a wedge-shaped protrusion comprising an upper surface 114 substantially as the first attachment mechanism 100, and a first engagement surface 511. In this attachment mechanism 500, the first engagement surface 511 is generally parallel with the plane of rotation of the actuator, similar to the fourth attachment mechanism 400 described above. However, the first engagement surface 511 comprises a ramped portion 511a which is angled relative to the remainder of the first engagement surface 511. As shown in Fig. 12, this ramped portion 51 la is positioned at a leading edge of the first engagement surface 511, i.e., at an end of the first engagement surface 511 which first interacts with or opposes the second engagement surface 521 when the actuator moves towards the locking position. By providing a ramped portion 51 la in this way, it can be ensured that the first engagement feature 522a is correctly aligned with and passes over the second engagement feature 521 such that the first engagement surface 511 and the second engagement surface 521 slide past one another as the actuator moves towards the locking position. In this embodiment, the second engagement surface 521 is also parallel with the plane of rotation of the actuator, and with the first engagement surface 511. As the actuator moves towards the locking position (by rotating on the bearing surface), the first engagement surface 511 and the second engagement surface 521 slide past one another. When the actuator is in the locking position, as shown in Fig. 12, the first engagement surface 511 and the second engagement surface 521 oppose one another. Figs. 13a and 13b show cross-section views of a second outer collar 640 which may be used in embodiments of the present invention. In particular, Fig. 13a shows a crosssection view of the outer collar 640 alone, and Fig. 13b shows a cross-section view of the outer collar 640 with an interface portion 620 mounted therein. Generally, the outer collar 640 is the same as the outer collar 140 described above (e.g., with respect to Figs. 2 and 4), and so description of all the features is not repeated. However, differing features of the outer collar 640 are described below with respect to Figs. 13a and 13b. It should also be understood that the interface portion 620 may be substantially as described above with respect to any of the preceding embodiments, and the interface portion 620 differs only in how it interacts with the outer collar 640 as described below. The outer collar 640 comprises an inwardly directed flange 645 on an inner surface thereof at or about a circular opening in its top side. The flange 645 comprises a plurality of guiding channels 141 which are configured (e.g., configured by way of their positioning and sizing) to receive the second engagement features, which slide through the guiding channels 141 when the interface portion 620 is moved into contact with an actuator (not shown). Similarly, the inwardly directed flange 645 comprises a plurality of locating channels 142, through which locating features of the interface portion 620 are configured to slide when the interface portion 620 is moved into contact with the actuator. In this example, an upper surface of the flange 645 is perpendicular to the outside wall of the outer collar 640 from which it protrudes. As shown in Fig. 13b, an upper surface of the flange 645 is arranged to abut a corresponding rim 625 which extends outwardly from an upper edge of the interface portion 620 when the interface portion 620 is coupled to the actuator. In particular, the upper surface of the flange 645 and an abutting surface of the rim 625 are parallel to one another. Such an arrangement may assist in manufacturing wherein the upper surface of the flange 645 and the rim 625 of the interface portion 620 may be used as datum references. In particular, by arranging these surfaces such that they are parallel to one another, and perpendicular to a longitudinal axis of the attachment mechanism, when the interface portion 620 is coupled to the actuator, it may be easier to determine that the interface portion 620 and the outer collar 640 are manufactured to within predetermined manufacturing tolerances to help ensure stability of the attachment mechanism. The features disclosed in the foregoing description, or in the following claims, or in the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for obtaining the disclosed results, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof. While the invention has been described in conjunction with the exemplary embodiments described above, many equivalent modifications and variations will be apparent to those skilled in the art when given this disclosure. Accordingly, the exemplary embodiments of the invention set forth above are considered to be illustrative and not limiting. Various changes to the described embodiments may be made without departing from the spirit and scope of the invention. For the avoidance of any doubt, any theoretical explanations provided herein are provided for the purposes of improving the understanding of a reader. The inventors do not wish to be bound by any of these theoretical explanations. Any section headings used herein are for organizational purposes only and are not to be construed as limiting the subject matter described. Throughout this specification, including the claims which follow, unless the context requires otherwise, the word “comprise” and “include”, and variations such as 5 “comprises”, “comprising”, and “including” will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps. It must be noted that, as used in the specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly 10 dictates otherwise. Ranges may be expressed herein as from “about” one particular value, and / or to “about” another particular value. When such a range is expressed, another embodiment includes from the one particular value and / or to the other particular value. Similarly, when values are expressed as approximations, by the use of the antecedent “about,” it will be understood that the particular value forms another embodiment. The 15 term “about” in relation to a numerical value is optional and means, for example, + / - 10%.

Claims

1. An attachment mechanism for removably connecting a main body of a haircare appliance with an attachment for the haircare appliance, wherein the attachment mechanism comprises:an actuator comprising a first engagement surface,an interface portion removably couplable to the actuator, the interface portion comprising a second engagement surface, anda resiliently deformable seal; whereinthe actuator is moveable between an open position and a locking position;the actuator is biased towards the locking position such that, when the interface portion is coupled to the actuator, the first engagement surface and the second engagement surface oppose one another; andwhen the interface portion is coupled to the actuator, the resiliently deformable seal is in contact with the interface portion to apply a biasing force to the interface portion and thereby bias the second engagement surface towards the first engagement surface such that the first engagement surface and second engagement surface are mutually engaged to prevent the interface portion being uncoupled from the actuator.

2. The attachment mechanism of claim 1, wherein the resiliently deformable seal comprises a body portion and a protruding flange arranged such that, when the interface portion is coupled to the actuator, the protruding flange is in contact with the interface portion to apply a biasing force to the interface portion and thereby bias the second engagement surface towards the first engagement surface.

3. The attachment mechanism of claim 1 or claim 2, wherein the resiliently deformable seal is made of a silicone rubber material.

4. The attachment mechanism of any preceding claim, wherein the first engagement surface and the second engagement surface are configured such that, when the interface portion is coupled to the actuator, the first engagement surface and the second engagement surface are substantially parallel to one another.

5. The attachment mechanism of claim 4, wherein:the first engagement surface comprises a first ramped portion which is angled relative to the second engagement surface, and / orthe second engagement surface comprises a second ramped portion which is angled relative to the first engagement surface;for aligning the first engagement surface and the second engagement surface when the interface portion is coupled to the actuator and the actuator moves towards the locking position.

6. The attachment mechanism of any preceding claim, wherein the first engagement surface is a surface of a first engagement feature, and wherein either:the first engagement feature comprises a protrusion from the actuator, orthe first engagement feature comprises a recess in the actuator.

7. The attachment mechanism of claim 6, wherein the first engagement feature comprises a wedge-shaped protrusion.

8. The attachment mechanism of any preceding claim, wherein the actuator comprises a plurality of first engagement features, each first engagement feature having a respective first engagement surface.

9. The attachment mechanism of any preceding claim, wherein the second engagement surface is a surface of a second engagement feature, and wherein either:the second engagement feature comprises a protrusion from the interface portion, or the second engagement feature comprises a recess in the interface portion.

10. The attachment mechanism of any preceding claim, wherein the interface portion comprises a plurality of second engagement features, each second engagement feature having a respective second engagement surface.

11. The attachment mechanism of any preceding claim, wherein the actuator is slidably mounted on a bearing surface.

12. The attachment mechanism of any preceding claim, wherein the actuator5 comprises an outwardly directed protrusion which is operable by a user to move the actuator from the locking position to the open position for uncoupling the interface portion from the actuator.

13. A haircare appliance comprising a main body, an attachment which is removably10 connectable to the main body, and an attachment mechanism according to any one of claims 1 to 12.

14. The haircare appliance of claim 13, wherein either:the actuator and resiliently deformable seal are mounted to the main body, and the15 interface portion is mounted to the attachment; orthe actuator and resiliently deformable seal are mounted to the attachment, and theinterface portion is mounted to the main body.

Images