Patent Publication Number: US-2018042358-A1

Title: Parasite comb

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to New Zealand Patent Application No. NZ 723179, entitled Parasite Comb, filed Aug. 11, 2016, the disclosure of which is hereby incorporated by reference in its entirety. 
     TECHNICAL FIELD 
     The present invention relates to a parasite comb. More particularly but not exclusively it relates to parasite comb for collecting and crushing fleas. 
     BACKGROUND 
     A variety of combs having various features for collecting parasites such as fleas and lice are known. These collecting combs merely separate the parasites from the hair of a subject. The parasites are collected by not being able to pass through the fine gaps between the teeth as the teeth of the comb are passed through hair. The parasites are moved along with the comb in front of the teeth until the end of the combing stroke. 
     A problem with conventional combs, such as flea comb, is that at the end of the combing stroke the fleas are able to jump off the teeth and resume their normal activity, albeit at a different location. Devices for trapping fleas are known such as U.S. Pat. No. 5,315,959 in which a debris-trapping shield is coupled to the handle. However the device described in U.S. Pat. No. 5,315,959 only traps fleas, sometimes only temporarily. 
     In this specification, where reference has been made to external sources of information, including patent specifications and other documents, this is generally for the purpose of providing a context for discussing the features of the present invention. Unless stated otherwise, reference to such sources of information is not to be construed, in any jurisdiction, as an admission that such sources of information are prior art or form part of the common general knowledge in the art. 
     It is an object of the present invention to provide a comb which overcomes or at least partially ameliorates some of the abovementioned disadvantages or which at least provides the public with a useful choice. 
     STATEMENTS OF INVENTION 
     In a first aspect the present invention may be said to broadly consist in a comb to collect and subsequently crush parasites, the comb comprising
         a body having a handleable portion,   a row of closely spaced teeth projecting outwardly from the body, the teeth configured to collect said parasites when combed through hair,   a crusher engaged to one of the teeth or handle, the crusher having at least one crushing surface configured to move to abut against at least one of the body and teeth to cause the parasites to be at least one of a) trapped and b) crushed between the at least one crushing surface and at least one of the body and teeth.       

     In one embodiment, the teeth define a first face of the row of teeth adjacent to a first crushing surface of said crusher. 
     In one embodiment, the first crushing surface and the first face are configured to crush parasites between them. 
     In one embodiment, the row of teeth comprises a base where the teeth meet the body. 
     In one embodiment, the crusher is flexible. 
     In one embodiment, the crusher is hingeable or flexible and configured to hinge or flex to abut the first face of the teeth. 
     In one embodiment, the crusher is hingeably engaged to one of the teeth or handle. 
     In one embodiment, the crusher comprises a hingeable or flexible portion. 
     In one embodiment, the crusher comprises a hingeable or flexible portion at or near, and parallel to, the base. 
     In one embodiment, the hingeable or flexible portion is a hinge intermediate the crusher and the body. 
     In one embodiment, the hinge is integral and/or a part of the crusher. 
     In one embodiment, the hinge is formed of pliable film. 
     In one embodiment, the hinge is a living hinge. 
     In one embodiment, the hinge is a pin type hinge. 
     In one embodiment, the hinge allows the crushing surface to fully abut flush with the upper surface of the teeth. 
     In one embodiment, the hinge allows the crusher hinge away from the teeth. 
     In one embodiment, the crusher has a crushing position where the crushing surface abuts the first face. 
     In one embodiment, the crusher has a resting position where the crushing surface does not abut the first face. 
     In one embodiment, the crusher is biased towards the first face. 
     In one embodiment, the crusher has a second crushing surface substantially parallel to the body. 
     In one embodiment, the body comprises an opposite surface opposite the second crushing surface. 
     In one embodiment, the second crushing surface cooperates with an opposite surface of the body to crush any parasites therebetween. 
     In one embodiment, the second crushing surface is offset from the opposite surface and is manipulatable towards and away from the opposite surface. 
     In one embodiment, the second crushing surface acts to crush parasites between the second crushing surface and the opposite surface. 
     In one embodiment, the hingeable or flexible portion is intermediate the second crushing surface and the opposite surface to allow the second crushing surface to rotate or pivot relative the opposite surface. 
     In one embodiment, the hingeable or flexible portion allows a nut cracker type movement to crush said parasites between the second crushing surface and opposite surface. 
     In one embodiment, the crusher is configured for a mechanical advantage to crush parasites between the second crushing surface and opposite surface. 
     In one embodiment, the first crushing surface is within 2 millimetres from the first face at a resting position. 
     In one embodiment, the first crushing surface abuts the upper side of the teeth at a crushing position. 
     In one embodiment, the crushing surface has protruding ribs extending towards the teeth, the ribs having an elongate length substantially parallel to the elongate direction of the teeth. 
     In one embodiment, the protruding ribs protrude intermediate each tooth of the row of teeth. 
     In one embodiment, the crushing surface has protruding ribs extending towards the teeth, the ribs having an elongate length substantially perpendicular to the elongate teeth. 
     In one embodiment, the comb comprises a shim directly adjacent at least a portion of the first face of the teeth. 
     In one embodiment, the shim comprises a third crushing surface between the shim and the first crushing surface of the crusher. 
     In one embodiment, the shim projects outwardly from the body, flush with the first face of the teeth. 
     In one embodiment, the shim is integral with the body. 
     In one embodiment, the crusher is configured to scrape or drive parasites from the first face and/or the shim towards one or more of the first, second and third crushing surface. 
     In one embodiment, the crusher is integral with the handle. 
     In one embodiment, the crusher is rigid. 
     In one embodiment, the crusher has a distal surface opposite to the second crushing surface at or towards the distal end of the teeth. 
     In one embodiment, the crusher&#39;s distal surface is flush with ends of teeth. 
     In one embodiment, the crusher&#39;s distal surface is before the ends of the teeth. 
     In one embodiment, the crusher has two side surfaces at or towards each end of the row of teeth. 
     In one embodiment, one or more side surfaces are flush with each end of the row of teeth. 
     In one embodiment, one or more side surfaces are inner more than each end of the row of teeth. 
     In one embodiment, the comb comprises a like secondary crusher on the other side of the row of teeth, opposite the first crusher. 
     In one embodiment, the like secondary crusher is hingeable at or towards the row of teeth. 
     In one embodiment, the secondary crusher comprises a secondary hinge. 
     In one embodiment, the secondary hinge is configured to allow the secondary crusher to hinge back past an acute angle from the row of teeth. 
     In one embodiment, the secondary hinge is configured to allow the secondary crusher to hinge back past an obtuse angle from the row of teeth. 
     In one embodiment, the secondary hinge is configured to allow the secondary crusher to fold substantially back onto the body. 
     In one embodiment, the parasites are fleas. 
     In one embodiment, one or both of the first and second crusher comprise upper manipulable surface(s) on an opposite side to the first crushing surface to allow a user to manipulate the crushers towards and away from the first and/or second crushing surfaces. 
     In one embodiment, the manipulable surface is grippy. 
     In one embodiment, the row of teeth follows a curved path. 
     In one embodiment, the one or more crushers follow the curved path. 
     In an alternative embodiment, the crusher is a sliding crusher and slideably engaged to one of the teeth or handle. 
     In one embodiment, the sliding crusher slidably moves to abut against at least one of the body and teeth and at least trap and preferably crush said parasites. 
     In one embodiment, the sliding crusher is retractable with respect to the teeth. 
     In one embodiment, the sliding crusher comprises a sliding member that engages with the body. 
     In one embodiment, the sliding member is manipulable to be slid by the user. 
     In one embodiment, the sliding member engages with a complementary guide channel. 
     In one embodiment, the sliding member slides in a direction parallel to an elongate axis of a tooth of the row of teeth. 
     In one embodiment, the sliding member slides in a direction to move the sliding crusher&#39;s at least one crushing surface towards and away from adjacent the row of tooth. 
     In one embodiment, the sliding crusher has a retracted position where the sliding crusher&#39;s at least one crushing surface does not engage or abut with the row of teeth. 
     In one embodiment, the sliding crusher has an extended and position where the sliding crusher&#39;s at least one crushing surface engages and/or abuts with the row of teeth. 
     In one embodiment, the sliding crusher comprises a like second crushing surface as described above. 
     In one embodiment, the sliding crusher comprises a like third crushing surface as described above. 
     In one embodiment, there is a secondary sliding crusher on the opposite side of the row of teeth like the sliding crusher. 
     In one embodiment, the sliding crusher&#39;s first crushing surface is biased towards the row of teeth. 
     In one embodiment, the sliding crusher is able to be fully retract so as not to impede the passage of hair through the teeth in operation 
     In one embodiment, the first crushing surface abuts parallel to the body in the retracted position. 
     In one embodiment, the sliding crusher is spring operated to bias the sliding crusher towards its extended position. 
     In one embodiment, the comb comprises an operable detent to detain and release to release the spring powered sliding crusher. 
     In one embodiment, the body is composed of plastics. 
     In one embodiment, the crusher is composed of plastics. 
     In one embodiment, the comb is composed of plastics. 
     In an alternative embodiment, the body is composed of one or more of plastics, wood and metal. 
     In one embodiment, the crusher is composed of a material that lets at least some light through. 
     In one embodiment, the crusher comprises a region composed of a translucent or clear material. 
     In a second aspect the present invention may be said to broadly consist in a comb to collect and subsequently crush parasites, the comb comprising
         a body having a handleable portion and an elongated teeth receiving portion,   a row of closely spaced teeth projecting outwardly on a notional plane from the teeth receiving portion, the teeth configured to collect said parasites when the teeth are combed through hair,   a collecting crusher projecting outwardly from the elongated teeth receiving portion and substantially parallel to the notional plane; and   a crushing surface configured to crush parasites between either the crusher and the teeth or the crusher and the body.       

     In one embodiment, the crushing surface is parallel to the notional plane to crush parasites between the teeth and the crusher. 
     In one embodiment, the crushing surface is perpendicular to the notional plane to crush parasites between the crusher and the body. 
     In one embodiment, a shim portion of the body extends out parallel to the notional plane. 
     In one embodiment, the crushing surface is parallel to the notional plane to crush parasites between the crusher and a shim. 
     In one embodiment, the shim is thin. 
     In one embodiment, the shim projects out from adjacent elongate teeth receiving portion to partially cover the teeth. 
     In one embodiment, the crusher extends the length of the row of teeth. 
     In one embodiment, the shim extends the same length as the crusher. 
     In one embodiment, the parasites are fleas. 
     In a third aspect the present invention may be said to broadly consist in a comb to collect and subsequently crush parasites, the comb comprising
         a body having a handleable portion,   a row of closely spaced teeth projecting outwardly from the body, the teeth configured to collect said parasites when combed through hair,   a crusher engaged to one of the teeth or handle, the crusher having at least one crushing surface configured to, upon hinging, move to abut against at least one of the body and teeth and at least trap said parasites.       

     In one embodiment, the crusher is configured to crush said parasites. 
     Other aspects of the invention may become apparent from the following description which is given by way of example only and with reference to the accompanying drawings. 
     As used herein the term “and/or” means “and” or “or”, or both. 
     As used herein “(s)” following a noun means the plural and/or singular forms of the noun. 
     The term “comprising” as used in this specification means “consisting at least in part of”. When interpreting statements in this specification which include that term, the features, prefaced by that term in each statement, all need to be present but other features can also be present. Related terms such as “comprise” and “comprised” are to be interpreted in the same manner. 
     This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more of said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.) 
     To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be in any sense limiting. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The invention will now be described by way of example only and with reference to the drawings in which: 
         FIG. 1 : shows a front perspective view of a comb in the extended position. 
         FIG. 2 : shows a side view of a comb of  FIG. 1 . 
         FIG. 3 : shows a top view of a comb of  FIG. 1 . 
         FIG. 4 : shows a front view of the comb of  FIG. 1 . 
         FIG. 5 : shows a side view of the comb in use. 
         FIG. 6 : shows a close-up side view of the teeth with the crusher in the extended position. 
         FIG. 7 : shows a close-up side view of the teeth in a crushing position. 
         FIG. 8 : shows a close-up side view of the teeth in another crushing position. 
         FIG. 9 : shows a shows a close-up view of a comb with a shim. 
         FIG. 10 : shows a rear perspective view of a comb with a shim and a crusher in an extended position. 
         FIG. 11 : shows a side view of the comb with opposing crushers, one crusher in a folded back position and the other crusher in an extended position. 
         FIG. 12 : shows a front perspective view of the comb of  FIG. 11 . 
         FIG. 13 : shows a front perspective view of the comb of  FIG. 11  with both crushers and extended positions. 
         FIG. 14A : shows a front perspective view of the sliding crusher in a retracted position. 
         FIG. 14B : shows a side view of  FIG. 14A . 
         FIG. 15A : shows a front perspective view of the sliding crusher in a mid-point position. 
         FIG. 15B : shows a side view of  FIG. 15A . 
         FIG. 16A : shows a front perspective view of the sliding crusher in an extended position. 
         FIG. 16B : shows a side view of  FIG. 16A . 
     
    
    
     DESCRIPTION 
     With reference to the above drawings, in which similar features are generally indicated by similar numerals, a comb is generally indicated by the numeral  1000 . 
     In one embodiment now described, there is provided a comb  1000  consisting of three parts. Firstly; a body  100  comprises a handle  101 ; secondly a row of closely spaced apart teeth  200  projecting out from the body  100  at an elongate teeth receiving portion  102 ; and thirdly a crusher  300  projecting out from the body  100  and adjacent the teeth receiving portion  102 . When using the comb in operation the teeth  200  are pushed or drawn in a direction  7  through the hair  2  of a species  1 , parasites  3  such as fleas  3  do not fit within the closely spaced gaps between the row of teeth  200  and as such are caught on the upper surfaces (also called the first face) of the teeth as shown in  FIG. 5 . The fleas  3  are then retained between the first face of the teeth and lower surface of the crusher  300 . Once a combing stroke or multiple combing strokes have been completed then the crusher  300  is pushed onto the teeth to crush the retained fleas  3 . 
     The body  100  comprises the handle  101  and the teeth receiving portion  102 . The receiving portion  102  preferably is linear and may be notional—for example if the teeth are integral with the body. The handle  101  may be a comb handle in which the body is merely a flat surface that extends back from the teeth, or the handle may be off to the side of the teeth. The handle is not important to the use of invention. Many different handles are known in the comb industry. Different handles are often used for different purposes and a person skilled in the art will realise that a handle of a different configuration does not depart from the spirit of the invention. 
     The teeth  200  project out from the body on a notional plane  4  from the teeth receiving portion  102 . The teeth are common to majority of flea combs publicly known. The teeth  200  may be rotatable or maybe differently shaped and spaced for different uses. The teeth comprise bases  201  at the teeth receiving portion  102 , and each tooth has a point or tip  202  distal to the base  201 . The row of teeth  200  comprises a first face  203  along one side of the row of teeth, for example if a flat sheet was laid upon the row of teeth  200  it would touch the upper surfaces  203  of the teeth  200 . The teeth are preferably composed of metal however plastics may be used also. The teeth may be integrally formed with the body or maybe inserted into or attached to the body, or furthermore the body may be injection moulded about the teeth. The teeth may be cylindrical or they may be conical or frustoconical in shape, or they may be shaped elsewise as known in the art. 
     The crusher  300  projects out from the body  100  from adjacent the teeth receiving portion  102  to extend substantially over the top/adjacent to the row of teeth  200 . 
     In one embodiment the crusher  300  has two positions; a resting position where the crusher is in a relaxed state, and a crushing position  6  where the crusher has been manipulated for crushing. Furthermore, the crusher  300  may have a third position  8  where the crusher is bent backwards or extended away from the teeth which happens during the combing process. This extended position may also be the resting position of the crusher  300 . Having an extended resting position easily allows for the crusher to be bent back easily during combing.  FIGS. 1 and 2  for example may show an extended position or a resting position. 
     In one embodiment, the crusher  300  is substantially parallel with the notional plane  4  of the teeth whilst in the resting position. In other embodiments, where the teeth are conical and the first face of the teeth are not parallel with the notional plane, then the crusher  300  may be substantially parallel with the plane formed by the first face of the row of teeth whilst in the resting position. 
     The crusher  300  comprises two surfaces, a lower first crushing surface  301  and an upper manipulable surface  302 . The first crushing surface  301  is configured to abut the first face  203  of the row of teeth  200 . The object of the crushing surface  301  is for the teeth to collect parasites, such as fleas  3 , on the upper surfaces  203  of the teeth  200  so that the fleas  3  maybe trapped between the upper surfaces  203  and the first crushing surface  301 . Once the fleas  3  have been collected a user may manipulate the manipulable surface  302  to effectively push the crusher  300  towards the upper surfaces  203  of the teeth  200  to crush the fleas  3  trapped between the first face  203  of the row of teeth  200  and the first crushing surface  301 . The upper manipulable surface  302  in one embodiment is grippy to aid the user in manipulating the crusher  300  towards the teeth  200 . 
     To allow the crusher  300  to be manipulated towards the teeth  200  the crusher  300  comprises a hingeable or flexible portion  304 . This hingeable or flexible portion  304  is preferably intermediate the body  100  and the crusher  300 . Preferably the hingeable or flexible portion  304  runs elongate with the teeth receiving portion  102 . In a most preferred embodiment the crusher  300  itself is flexible over its entire area. Thus the crusher may be integrally attached to the body or joined to the body without a specific hinge joint but the crusher itself may be flexible enough to be moved to crush parasites upon the first face  203 . In one embodiment the crusher may be described as a flap. 
     The hingeable or flexible portion  304  in another embodiment may be an isolated hinge that is intermediate the body  100  and the crusher  300 . The hinge  304  may be of many different types as known in the art. These hinges  304  may include pin and slot type hinges, living hinges, resilient, pliable or flexible portions that are integral with the crusher or other alternatives. As long as the crusher  300  is able collect fleas  3  in a first position between the first face  203  and the first crushing surface  301  and in a second position be able to move to crush fleas  3  between the first crushing surface  301  and the first face  203 . In embodiments where there is a specific isolated hinge or hingeable or flexible portion, the crusher  300  itself may rigid. The hinge allows the crushing surface to abut flush with the upper surface of the teeth. In an alternative embodiment the crusher  300  is not pivotally hinged but slidably movable instead. 
     The hingeable or flexible portion or hinge also allows the crusher  300  to bend backwards in operation to allow the comb  1000  to be used at angles other than a right angle with respect to the notional plane  4  and the surface of the species to be combed. 
     Preferably the first crushing surface  301  covers the first face  203  of the row of teeth  200 . This allows the crushing surface  301  to collect, and be able to crush, any flea that is retained by any tooth/teeth. In alternative embodiments the crushing surface  201 , or the side surfaces  203  of the crusher  300  may not extend to each end of the row of teeth  200 . In this embodiment the crusher  300  is narrower than the elongate length of the row of teeth which allows the comb to be used for specific isolation and combing of particular areas. For example the comb with a narrow crusher may be used to capture individual and visible fleas  3  (not shown). 
     Following on from this idea the crusher&#39;s distal region or distal surface  305 , opposite to the base of teeth  201 , may not be flush with the ends or points  202  of the teeth. Preferably the distal surface  205  is flush with the points  202  so that all fleas  3  captured can be crushed. However the distal surface  305  may not be flush with the points  202  and it may extend past the points  202  or may fall short of the points  202 . 
     In one embodiment the first crushing surface  301  is within 2 millimetres from the upper side of the teeth/first face  203  at a resting position  5 . In other embodiments the first crushing surface  301  abuts the first face  203  when in the resting position  5 . This is due to the crusher  300  being flexibly biased towards the teeth  200  in this embodiment. 
     The crusher  300  is preferably composed of plastics however other materials such as metal may be used also. Preferably the crusher  300  is plastic welded to the body, however in other embodiments it is integral with the body. Preferably, the body  100  is also composed of plastics. In other embodiments the body  100  may be made of wood or metal or another suitably rigid material. 
     In a preferred embodiment the crusher  300  is composed of a material that lets at least some light through. Preferably this material is translucent or clear. Preferably material is a clear plastics and allows the parasites, if present, to be observed between the teeth and the crushing surfaces. The sliding crusher, discussed below, is preferably made of a similar material to the hinged crusher  300 . The sliding crusher however may have the sliding member being a rigid opaque plastics and the crushing head being translucent or clear. 
     In further embodiments, the crusher  300  comprises a second crushing surface  307  intermediate the body  100  and the crusher  300 , and perpendicular to the notional plane  4  when the crusher  300  is in the resting position biased towards the teeth. The body  100  comprises a complimentary opposite surface  103  opposite the second crushing surface  307  adjacent the elongated teeth receiving portion as shown in  FIGS. 6-8 . 
     The second crushing surface  307  and the opposite surface  103  act together to crush parasites between the two surfaces  103   307  when crusher  300  is manipulated towards a direction substantially perpendicular to both said surfaces as shown in  FIG. 8 . The second crushing surface  307  acts as a second crushing surface to crush parasites between the second crushing surface and the opposite surface. 
     Prior to manipulation of the crusher  300 , the second crushing surface  307  is offset from the opposite surface  103  as shown in  FIG. 7 . The crusher  300  is manipulable towards and away from the body  100 . Any parasites they are caught up in the combing process tend to be pushed towards the base of the teeth by the hair of the animal and end up in-between the opposite and second crushing surfaces  103   307 . The comb  1000  may comprise a separate hinge to allow the crusher  300  to move towards and away from the body in a direction parallel with the notional plane  4  that brings the second crushing surface  307  and opposite surfaces  103  together. In a preferred embodiment the comb  1000  uses the existing flexible hinge portion  304  to allow the second crushing surface  307  and opposite surfaces  307  to come together. Preferably the hingeable or flexible portion  304  is intermediate the second crushing surface  307  and the opposite surface  103  to allow the second crushing surface  307  to rotate or pivot, or flex towards, relative the opposite surface  103  to allow a nut cracker type movement to crush said parasites between the second crushing surface  307  and opposite surface  103 . Alternatively the crusher may have a vertical movement only to crush parasites between the second crushing surface  307  and opposite surfaces. 
     The before and after vertical movement of the crusher can be seen in  FIGS. 7 and 8 .  FIG. 7  shows the crusher before being manipulated towards the opposite surface  103 .  FIG. 8  shows the crusher manipulated onto the opposite surface  103 .  FIG. 7  and  FIG. 8  also show the first crushing surface working against the teeth  200 . 
     In a preferred embodiment the second crushing surface  307  is approximately 3 mm wide. However other embodiments where the second crushing surface  307  is between 0.5 and 7 mm wide is envisioned within the scope of the invention. 
     In a further embodiment the first crushing surface  301  has ribs  308  protruding towards the teeth  200 , the ribs  308  having an elongate length substantially parallel in direction to the elongate teeth  200 . The ribs  308  aid in crushing parasites by providing more surface area to the crushing surface  301  to come into contact with the first face  203 , in turn reducing the places a parasite can avoid being crushed. 
     In one embodiment the ribs  308  are aligned so they are intermediate the teeth, i.e the ribs are aligned so they align up with the gaps between the teeth. In another embodiment the ribs  308  are aligned so they are aligned with the first face of the teeth. The ribs can be seen in  FIGS. 12 and 13 . The ribs may also be present on the single crusher as well as a double crusher comb—described later. 
     In another embodiment the ribs extend in a direction perpendicular to the elongate length of the teeth (not shown). 
     In a further embodiment the comb  1000  comprises a shim  400  intermediate the first face  203  and the first crushing surface  301 , as shown in  FIGS. 9 and 10 . In a preferred embodiment the shim  400  abuts the first face  203 . The shim aids in collecting and crushing fleas  3 . As described previously when the comb  1000  is brushed through the hair  2  parasites  3  tend to collect at the base of the teeth. Such a shim  400  is introduced to collect the fleas  3  between the shim  400  and the crusher  300 . The shim  400  has a third crushing surface  401  which is a complimentary surface to the first crushing surface  301 . Collecting the fleas  3  between the first crushing surface  301  and third crushing surface  401  enables an area of greater surface to crush fleas  3  between (as there are no gaps between the teeth), compared to crushing between the first crushing surface  301  and the first face  203 . 
     The shim  400  is thin so that the first crushing surface  301  is not prevented from abutting against the first face  203  of the teeth, so both the shim  400  and the teeth  200  are able to have fleas  3  crushed between them and the crusher  300 . The shim is preferably composed of a thin sheet of plastic or metal. The shim may be integral or attached to the body. In an alternative embodiment the shim is integral with the teeth in which the bottom region of the teeth are all joined together to form a flat surface at their base towards the body (not shown). 
     The shim  400 , opposite surface  103  and second crushing surface  307  provide sides to form a retention area to retain parasites in prior to crushing. 
     In a further embodiment the comb  1000  has a crusher on either side the teeth. One or more of these crushers is able to fold back flush against the body  100  to allow the crusher to get out of the way of hair  2  whilst combing. The two crushers are manipulable towards the teeth. The purpose of the two crushers is to increase the pressure on the fleas  3  during crushing. 
     In this embodiment a first crusher is similar to the crusher as described previously, and the secondary crusher is able to fold back upon itself. The secondary crusher  500  is hingeable at or towards, and parallel to, the elongated teeth receiving portion, adjacent the bases the row of teeth. The secondary crusher  500  has similar features as the first crusher  300 , such as a secondary hinge et cetera. The secondary hinge  501  is able to hinge back past an acute angle with the notional plan  4 . In a preferred embodiment the secondary hinge  501  allows the secondary crusher  500  to hinge back past an obtuse angle with the notional plane  4 . The secondary hinge  501  in a further embodiment allows the secondary crusher to fold substantially back onto the body. 
     One or more of the crushers comprise crushing surfaces that face the teeth and have ribs as described previously. The ribs aid in crushing fleas  3  if the fleas  3  are intermediate the teeth and the crusher. 
     In an alternative embodiment the crusher is slidable and manipulable so it can move between a retracted position where the sliding crusher&#39;s first crushing surface is not adjacent the teeth and an extended position where the sliding crusher&#39;s first crushing surface is adjacent the row of teeth. The sliding crusher version  600  is shown in  FIGS. 14-16 . The sliding crusher  600  can be seen moving between a retracted position in  FIGS. 14A and 14B  to the extended position  FIGS. 16A and 16B  and a mid-point position in  FIGS. 15A and 15B . 
     The sliding crusher  600  has similar crushing surfaces to the hinged crusher  300 , such as the first crushing surface  608 . The second and third crushing surfaces of the sliding crusher  600  are not specifically shown. 
     The sliding crusher  600  comprises the crushing head  601  and the sliding member  602 . The sliding member  602  is slidable within a channel/recess/guide  604 . The guide  604  guides the sliding member and head  601  towards and away from the row of teeth  200  in the direction  605 . In its retracted position the head is adjacent the body  100  and the crushing surface  608  rests against the body  100  as shown in  FIG. 14A . 
     Intermediate the sliding member  602  and the head  601  is a kinked region  606 . The kinked region allows the head  601  to fully abut the row of teeth  200 . The kinked region  606  allows the crushing surface  608  to come down on top of the row of teeth to crush parasites. The kinked region is just one way of enabling the sliding member to be on a different plane to the crushing surface, a skilled person in the art will realise the kinked region is not essential and there are many ways to configure the sliding crusher. 
     When the sliding crusher  600  is in its retracted the position the sliding member  602  up stands from the body  100  to allow the head  601  to rest upon the body. There are numerous ways of designing the sliding member  602  to slide within the body  100 . In one embodiment, the sliding member or kinked region may be flexible. In such an embodiment the head  601  may be biased to push against the row of teeth  200 . In one embodiment, the user when pushing the sliding member forward also pushes the sliding member  602  and hence the head  601  towards the teeth to apply the force of the user&#39;s finger through the sliding member and head  601  onto the teeth  200 . 
     In the embodiment shown the sliding member has a cover  607  to cover the interface between the guide  604  and the sliding member  602 . The cover  607  may be a retention plate or guide for the sliding member  602 . There will be many ways a person skilled in the art will be able to retain the sliding member with the body, such as a groove and rail system not shown. 
     The sliding member may have gripping features  603  to aid the user in manipulating the sliding member  602 . 
     The primary advantage of the disclosed invention is that the crusher  300  or  500  or  600  is able to abut either the shim or the surfaces of the teeth, or body to crush parasites between the crushers and the teeth or shim or body. Other combs may collect the parasites at the teeth but at the end of the brushing stroke the parasites are able to remove themselves from the teeth. The crushers of the current invention both retain and/or crush the parasites. 
     Where in the foregoing description reference has been made to elements or integers having known equivalents, then such equivalents are included as if they were individually set forth. 
     Although the invention has been described by way of example and with reference to particular embodiments, it is to be understood that modifications and/or improvements may be made without departing from the scope or spirit of the invention.