Abstract:
A paintbrush comprises a handle portion including a stem portion and a head portion, with the head portion having a receiving means thereon. The paintbrush also has a paint application cartridge having a paint application portion, and a holding means for holding the paint application portion. A connecting means for connecting the paint application cartridge releasably to the receiving means of the handle portion is provided.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates generally to paintbrushes, and more particularly to paintbrushes having a handle portion and a paint applicator portion, the handle portion and paint applicator portion being releasably connectable to each other. 
     In this specification, the term “paintbrush” is intended to include a paint application portion which may be comprised of bristles to form a brush, is a roller having an outer fabric surface, or is any other medium by which paint may be applied to a surface. 
     Paintbrushes are, of course, well known articles for applying paint to surfaces. A typical brush comprises a contoured handle which is elongate, and a plurality of bristles at one end thereof, held together to form a brush. The plurality of bristles are permanently attached to the one end of the handle, usually by means of a metal ring or bracket. Since the bristles, or brush, is permanently affixed to the handle in most paintbrush arrangements, a particular paintbrush will be limited to specific uses, and will often only be used once before being discarded. This is because many users prefer to simply discard a paintbrush rather than go through the messy and time consuming task of cleaning the brush. 
     The brush portion of the paintbrush may have a variety of different forms and constituents. Thus, brushes may vary in width, from, for example, a half inch width right up to a width of five to six inches and more. Smaller width brushes are suitable for painting strips, edges or corners, and are useful where finer paintwork is required. On the other hand, a much wider bristle or brush component would be used to cover surfaces with paint much more quickly, and where broader stroke and wider area application of the paint is required. 
     One of the problems with respect to conventional paintbrushes is that painting jobs may typically require brushes having different sizes and attributes. Thus, smaller width brushes are required for edges, while wider width brushes are required for larger surface areas to be painted. Moreover, the nature and quality of the bristles which for the brush have optimal uses in different situations. In some instances, nylon-type bristles may be appropriate, while in others, softer more natural-type bristles are needed. In yet other circumstances, the painting portion need not necessarily be a brush, but may comprise a sponge, fiber or other appropriate material. To properly carry out a painting job may therefore require a painter to have an arsenal of different shaped, sized and quality brushes, which may be difficult to store, expensive to obtain, and somewhat inconvenient to use. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the invention, there is provided a paintbrush comprising: a handle portion including a stem portion and a head portion, the head portion having a receiving means thereon; a paint application cartridge having a paint application portion, a holding means for holding the paint application portion, and a connecting means whereby the paint application cartridge can be releasably connected to the receiving means of the handle portion. 
     Preferably, the receiving means comprises a recess in the head portion, and a fastening means in the recess portion for releasable connection to the connecting means. The fastening means may comprise a bolt located in the handle portion, the bolt having a threaded end which engages with the connection means of the paint applicator cartridge. The handle portion may include a channel extending therethrough from the receiving means at the head portion to an opposite end of the head portion, with the bolt being located in the channel. The bolt preferably comprises a ring portion thereon, the ring portion permitting rotational movement of the bolt within the channel, but preventing axial movement of the bolt therein. 
     In one embodiment, the handle portion further comprises a knob connected to the bolt at an end thereof remote from the threaded portion, whereby rotation of the knob causes rotation of the bolt and the subsequent attachment to or release from the connecting means of the paint application cartridge. The bolt may comprise at least one projection extending radially outwardly from the bolt, with the knob being molded around the projection. Further, the handle portion may further include a retaining ring groove, wherein the ring portion on the bolt is accommodated. 
     Preferably, the channel comprises a central portion having a diameter slightly wider than the bolt and two end portions each having a diameter substantially the same as the bolt. 
     The paint application portion, in one form, comprises a medium selected from the group consisting of: nylon bristles, synthetic bristles, natural bristles, and fabric. The paint application cartridge may be a brush or a roller. 
     The holding means preferably comprises a cup-shaped member having side walls and a base which define a chamber, with a portion of the paint application portion being located within the chamber. The connecting means may comprise a connector piece extending from the base wall of the cup member in a direction away from the chamber. The connector piece may have a central groove therein having an internal thread, the groove receiving a threaded bolt member which forms part of the receiving means. Further, the connector piece may be of hexagonal shape, and taper from a wider diameter portion at a point near the cup-shaped member to a narrower diameter portion at a point remote from the cup member. 
     According to another aspect of the invention, there is provided a paint brush handle connectable to a paint applicator having a connecting member thereon, the paint brush handle comprising a stem portion contoured for holding by a user of the paint brush handle; a head portion at one end of the stem portion, the head portion having a receiving member for receiving the connecting member of the paint applicator; and fastening means within the receiving member for releasably attaching to the connecting member. 
     In still a further aspect of the invention,there is provided a paint applicator cartridge connectable to a paint brush handle having a receiving means thereon, the paint applicator cartridge comprising a paint applicator portion for absorbing paint and whereby the paint is applied to a surface; a holding member for securely holding the paint applicator portion; and connecting means on the holding member for releasably connecting the paint applicator cartridge to the receiving means on the paint brush handle. 
     The invention is also for a method of assembling a paintbrush having a handle and a paint application cartridge, the method comprising forming a receiving member in the handle capable of releasably receiving the cartridge portion; forming a connector piece on the cartridge having a shape and configuration corresponding to the receiving means; and locating the connector piece releasably within the receiving means. 
     The present invention therefore addresses the problem of multiple-type paintbrush heads which may be required by providing a separate handle portion, and a paint application portion in the form of a cartridge which may be releasably and effectively removed from the handle portion when a different paint application portion is needed. In one form, the paintbrush of the invention comprises a handle with a receiving means, and a paint application portion with a registering or corresponding connector, whereby the handle portion may be connected, serially, with a wide variety of different paint application portions depending upon the preferences and requirements of the user. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front view of the handle portion and paint application portion of the paintbrush assembly of the invention; 
     FIG. 2 is a side view of a bolt located in the handle portion of the paintbrush assembly with connecting means for attachment to the paint application portion; 
     FIG. 3 is a detail of the threaded end of the bolt shown in FIG. 2; 
     FIG. 4 is a sectional view of the handle portion only with the bolt and knob removed and showing the bolt receiving channel; 
     FIG.  5 ( a ) is a top view of a paint application portion attachable to the handle portion, shown in phantom lines, to form the paintbrush assembly of the invention; 
     FIG.  5 ( b ) is a side view of the paint application portion shown in FIG.  5 ( a ); 
     FIG.  6 ( a ) is a is a top view of a wider paint application portion attachable to the handle portion to form the paintbrush assembly; 
     FIG.  6 ( b ) is a side view of a wider paint application portion shown in FIG.  6 ( a ); 
     FIG. 7 is a detail view, partially cut away, showing the connection between the handle portion and the paint application portion; 
     FIG.  8 ( a ) is an end view of the paint handle portion showing the hexagonal recess for receiving the paint application portion; 
     FIG.  8 ( b ) is a detail side view of the recess shown in FIG.  8 ( a ); and 
     FIG. 9 is a detail section through opposite sections of a handle, showing a recess and projection for initially joining of the sections to each other. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference is now made to the drawings which show various embodiments of the paintbrush of the invention, including different forms of handle portions and paint application portion which may be attached thereto. 
     In this specification, any reference to “paintbrush” includes a painthead portion which includes not only bristles to form a brush, but also includes a head which may comprise a variety of different media which can hold paint, and which are capable of applying that paint to a surface. 
     With reference to FIGS. 1 and 4 of the drawings, there is shown the handle portion of the paintbrush assembly. In FIG. 1, the handle portion includes illustration of the bolt and end knob, while FIG. 4 shows the basic molded handle portion without any of its attachments. In FIG. 4, the handle portion, having reference numeral  10 , comprises a stem  12  having a head end  14  and a knob end  16 . The stem  12  is generally contoured, with rounded surfaces  108  to facilitate an easy grip thereon by the user, and presents no sharp edges which may cause discomfort. The contoured stem  12  is designed so as to take into account the fact that the brush will be held fairly tightly, and for extending periods of time, and so will be configured and designed to maximize comfort. 
     The head end  14  has extending inwardly from the end surface  20  a recess  18 . The recess  18 , which is preferably of hexagonal cross-section, as best seen in FIGS.  8 ( a ) and  8 ( b ), has a wider diameter at the end surface  20 , and tapers slightly as its side walls  22  approach a base end  24  of the recess. This recess  18  may be lined with metal, a hard plastic or other material so as to enhance the attachment of the handle portion  10  to the paint application cartridge, as will be described below. 
     The stem portion  12  has an axial channel  26  extending along the entire length of the handle portion  12 , from the end surface  28  through to the base end  24  of the recess  18 . The channel  26  has a wider diameter central portion  30 , a narrower head end portion  32  on one side thereof, and a narrower knob end portion  34  at its other end. A step  36  of bevel shape is located between the central portion  30  as it transitions to the head end portion  32 , while step  38  is located between the central portion  30  as it transitions to the narrower knob end portion  34  of the channel  26 . A retainer ring groove  40 , coaxial with the knob end portion  34 , surrounds the channel  26 , and is adapted to accommodate a retainer ring on the bolt. 
     The handle portion  10  may be constructed of any suitable and convenient material, including but not limited to wood, polyurethane, PVC, or other plastics material. In one preferred form, the material may be selected for its ability to have paint more easily removed therefrom by paint thinners and removers. 
     With reference to FIGS. 1 and 2 of the drawings, it will be noted that an elongate bolt  44  is located within the channel  26 , and is of a length such that the bolt extends outside the channel  26  beyond both the end surface  28  and the base  24  of the recess  18 . The diameter of the bolt  44  is just slightly less than, or substantially the same as, the diameter of the head end portion  32  and knob end portion  34  of the channel  26 , so that it is received snugly therein. The bolt may move slightly within the head end portion  32  and knob end portion  34 , but the tolerance levels will be high so that side to side movement of the bolt within these end portions is minimal or substantially zero. 
     The bolt  44  includes a disc-shaped retainer ring  46  affixed thereto, the retainer ring  46  being received and accommodated within the retainer ring groove  40 . The presence of the retainer ring  46  within the groove  40  has the effect of fixing the bolt  44  within the channel  26  so that axial movement therethrough is prevented. 
     The bolt has a smooth cylindrical surface  48  along substantially its entire length, but terminates in a threaded end  50 , the threaded end being essentially contained, in use, within the recess  18 . The threaded end  50  terminates with a pointed tip  52 . In a preferred embodiment, the pointed tip  52  reaches to approximately the level of the end surface  20 , or just below, and will typically not extend outward beyond the end surface  20 , and outside the recess  18 . 
     The bolt  44  is essentially an elongate cylindrical unthreaded member, with a threaded end  50  at that portion of the bolt  44  which extends into and is contained within the recess  18 . The retainer ring  46  prevents axial movement of the bolt  44  within the channel  26 , although rotational movement of the bolt about its axis while contained in the channel  26  is fully permitted. This rotational movement is indeed not only permitted, but necessary to enable the threaded end  50  of the bolt  44  to engage the paint applicator cartridge, as will be discussed below. 
     The handle portion  10  further comprises a knob  56  which is located adjacent the end surface  28  at the knob end portion  34  of the handle  10 . The knob  56  has a flat end surface  58  which is flush with, although not connected to, the end surface  28 . The knob  56  includes a groove  60  having an open end  62  and a closed end  64 . The groove  60  is of substantially the same diameter as the bolt  44 , and is adapted to receive and accommodate that end of the bolt  54  which extends beyond the end surface  28 , outside of the handle portion  10 . The bolt, at its knob end  66  has a pair of diametrically opposed projections  68  extending from the surface thereof. The knob end  66  of the bolt is received in the knob  56 , which is molded about the knob end  66  of the bolt to fix therein, and the knob  56  cannot move relative to the bolt  44 . Since, in use, the knob  56  will be rotated in different directions to attach and release the paint applicator cartridge, as will be discussed below, an effective fastening between the knob  56  and the knob end  66  of the bolt  44  is required. The projections  68  help to enhance this attachment, since the projections  68  are embedded in the knob  56  to strengthen the connection therebetween. 
     Preferably, the outer wall  70  of the knob has a ribbed or textured surface to facilitate a tighter hold thereon by the user. 
     Reference is now made to FIG. 5 of the drawings, which shows a paint application cartridge which is adapted to connect with the handle portion  10  of the paintbrush assembly. 
     The paint application cartridge, designated by reference numeral  74  essentially comprises a based holder  76  and a brush  78  connected thereto. FIG.  5 ( a ) shows a brush  78  as the medium of the paint applicator, but it must be appreciated that the invention is not confined to a paint application cartridge  74  having a brush. For example, instead of the brush, the paint applicator may be a sponge, fabric, or other textured medium. Furthermore, the paint applicator may be of any suitable shape, such as rectangular, or even a roller mounted in the base holder  76 . In the embodiment shown in FIG.  5 ( a ), the paint applicator is a brush  78  comprised of a plurality of synthetic or natural bristles held together at their base  80 . The bristles are all held together at base  80  in a conventional manner such as by glue, being embedded in a matrix, being tightly held together, or one or more of these arrangements. 
     In FIG.  5 ( a ), a brush having a width of approximately one inch is shown, with a narrower edge. FIG.  6 ( a ) shows essentially the same paint application cartridge  74 , but with a brush width of approximately four inches, and a slightly increased thickness. It will be appreciated that any desired brush width may be used, and the paint application cartridge  74  is not confined to the dimensions shown in FIGS. 5 and 6. While the structure of each paint application cartridge  74  is based on the same principles, the dimensions thereof may be changed to suit the particular circumstances, as required by the job. 
     The base holder  76  comprises a cup-shaped member  82  having side walls  84  and a base wall  86 . The base wall  86  and side walls  84  define a chamber  88  in which the brush  78  is received. The brush  78 , which has a fixed bristle section  90  and a loose bristle section  92 , is inserted into the cup-shaped member  82  such that the fixed bristle section  90  occupies the chamber  88 . Any suitable or conventional means for permanently fixing the brush  78  within the cup-shaped member  82  may be used to ensure that the brush  78  remains in the cup-shaped member  82  during painting. Since the painting action imparts some significant forces to the brush_ 78 , which is subject to repeated and multiple back and forth movements, it must be ensured that the brush  78  is firmly fixed within the cup-shaped member  82 . 
     The cup-shaped member  82  has an outer end wall  94  to which is attached a connector  96 . The connector has a wider diameter  98  at its end near the outer end wall  94 , and tapers down to a slightly narrower diameter  100 , terminating in a connector end  102 . The connector end  102  is generally a flattened end, while the side wall  103  of the connector  96  is of hexagonal shape. The shape and dimensions of the connector  96  are designed so that it registers with and corresponds to the shape of the recess  18  in the head end  14  of the handle  10 . 
     The connector  96  further comprises a threaded groove  104  which is structured so as to be capable of matingly engaging with the threaded end  50  of the bolt  44 . 
     In use, one of any of a number of variety of different paint application cartridges  74  may be attached to the handle portion  10 . The paint application cartridge  74  is placed adjacent the handle portion  10  such that the connector  96  is positioned over the recess  18 . As the connector  96  is lowered into the recess  18 , the pointed tip  52  of the bolt, and thereafter the threaded end  50  thereof, will contact the threaded groove  104  in the connector  96 , and the outer thread of the end  50  will matingly engage the internal thread in the groove  104 . The pointed tip  52  may be useful in centering of the connector  96  within the recess  18 . 
     The paint application cartridge  74  is then drawn into the recess  18  by rotating the knob  56 . Rotation of the knob  56  correspondingly rotates the bolt  44  and the threaded end  50 , and the threaded end engages the internal threads of the groove  104 . The continued rotation of the knob draws the connector  96  into the recess  18 . The fit of the connector  96  within the recess  18  is a tight one, facilitated by the engagement of the hex-shaped side wall  106  with the hex-shaped side wall  22  in the recess. These shaped surfaces, ensure that the paint application cartridge  74  will be incapable of rotating relative to the handle portion, thus adding to the secure attachment between the paint application cartridge  74  and the handle  10 . The tapering nature of the connector  96 , and the corresponding tapering of the recess  18 , also facilitates the connection, and assists the user in placing the connector  96  relative to the handle since it is easier to center or place the narrower diameter portion  100  of the connector in the sightly larger diameter at the end surface  20  of the handle  10 . 
     The knob  56  continues to be turned until such time as the connector end  102  firmly approaches or abuts the base end  24  in the recess  18 . At this point, the paint application cartridge  74  is firmly connected to the handle  10 , and the paint brush assembly is ready for use in a painting job. 
     When the paint application cartridge  74  currently in use and located on the handle is no longer required, or the painter wishes to use a different shape, textured or size paint application cartridge  74 , the connected paint application cartridge  74  can simply be removed by rotating the knob  56 . Rotation of the knob causes disengagement of the threaded portions at the end of the bolt, and has the effect of forcing the cartridge out of the recess. When the threaded portions are no longer in contact, the connector end  102  of the connector  96  will be pushed above the level of the end surface  20 , and simply fall out of the handle. This is a convenient method of removal, since the user does not need to tug or force the cartridge out of the recess, with the possibility of spraying paint, paint running onto the fingers etc. Further, a tight fit between the paint application cartridge  74  within the recess is necessary for the stability of the paintbrush assembly, but at the same time, this tight fit should not interfere with the ability to remove the painthead cartridge  74  at the desired time. The bolt-type connection, and the axial fixing of the bolt  44  within the channel  26  assures, on the one hand, the necessary tight fit, but also on the other hand, ease in releasing or removing the painthead cartridge  74  from the recess  18 . 
     FIG.  8 ( a ), which is an end view of the handle portion  10 , clearly shows the hexagonal-shaped contours of the recess  18 . As has been described, the recess  18  (and the connector  96 ) both taper, and, in a preferred embodiment, the amount of taper is approximately 7° from the perpendicular axis. In FIG.  8 ( b ), which shows a detail of the recess  18 , this degree of taper is illustrated. 
     FIG. 9 shows a detail of the male/female type connection between opposing sections in one embodiment of a handle. Each half, or opposing section, of the handle is injection molded and one section incorporates a projection while the opposing section has a corresponding recess. When initially bringing the two sections together, the projection is received within the recess for accurate alignment of the two sections, which may then be heat treated or otherwise processed to permanently hold the two sections together. 
     The handle may include a textured and specially shaped portion to facilitate a proper grip of the handle by the user. The textured portions may comprise a plurality of fine grooves which are substantially parallel to each other to give the handle a “matted” or roughened feel so that it is less likely to slip or slide in the hand of the user. The shape of the handle may also be designed and contoured for maximum comfort, since the handle may be held for prolonged periods. 
     The invention is not limited to precise details described above and/or illustrated in the drawings. Variations of the basic mechanism and design are also within the scope of the invention.