Patent Publication Number: US-2023145756-A1

Title: Breakaway buckle device for a pet collar

Description:
TECHNICAL FIELD The invention relates to a breakaway buckle device, in particular a breakaway buckle device for a pet collar. 
     BACKGROUND 
     Pet collar typically includes a band of material worn around the neck of a pet. The collar may be worn as an accessory, for example, to identify the pet and/or the pet&#39;s owners or to restrain the pet. 
     US20130333634A (U.S. application Ser. No. 13/495,488, filed on 13 Jun. 2012) discloses a pet collar. One disadvantage associated with the disclosed pet collar is that it may not be comfortably used with animals of different neck sizes (or the same animal at different ages with different neck sizes). 
     SUMMARY 
     In a first aspect, there is provided a breakaway buckle device for a pet collar. The breakaway buckle device comprises a first buckle portion, a second buckle portion, and a coupling mechanism. The coupling mechanism is arranged to releasably couple the first buckle portion with the second buckle portion. The coupling mechanism can be manipulated to adjust a breakaway force required for the first buckle portion to break relatively away from the second buckle portion. The breakaway buckle device may break away or break free to release the pet collar when a separation force applied to separate the first and second buckle portions reaches or exceeds the breakaway force. This ability to break away or break free reduces the risk of unintendedly injuring (e.g., choking) the animal wearing the pet collar. 
     The first buckle portion may be formed by a single component or multiple releasably connected or non-releasably connected components. The second buckle portion maybe formed by a single component or multiple releasably connected or non- releasably connected components. In one example, the first buckle portion is a first buckle member. In one example, the second buckle portion is a second buckle member. In one example, the breakaway buckle device includes one or more further buckle portions. 
     The first buckle portion may include a connector for connection with a strap. The connector may be a looped portion. The second buckle portion may include a connector for connection with a/the strap. The connector may be a looped portion. The connectors of the first and second buckle portions may be arranged at opposite ends of the breakaway buckle device. Optionally, the breakaway buckle device further includes a strap connected with the connectors of the first and second buckle portions. The strap can be a band, a webbing, a tether, a belt, etc., made of materials such as fabric, plastic (e.g., rubber), leather, etc. The strap may be elastic. Or it may be substantially inelastic. The strap may be formed by one or more strap portions or members, which may be removably or non-removably connected with each other. The length of the strap may be adjustable. 
     Optionally, the first buckle portion is arranged to break relatively away from the second buckle portion along a breakaway axis. The breakaway axis may be generally parallel to or coaxial with a long axis (e.g., an axis along a length) of the breakaway buckle device. The breakaway axis may be generally parallel to or coaxial with a coupling axis for coupling the first and second buckle portions. 
     Optionally, the coupling mechanism comprises complementary engagement means (or arrangements, e.g., members, mechanisms, components, etc.) formed at (e.g., on or in) the first and second buckle portions. 
     The complementary engagement means may provide a predetermined number of (i.e., two or more) breakaway forces that can be adjusted in discrete steps. Alternatively, the complementary engagement means may provide infinite number of breakaway forces that can be adjusted steplessly. 
     Optionally, the complementary engagement means comprises male and female engagement features. 
     Optionally, the complementary engagement means comprises: a plurality of engagement portions arranged at one of the first buckle portion and the second buckle portion and a corresponding engagement portion arranged at another one of the first buckle portion and the second buckle portion. The corresponding engagement portion is arranged to selectively engage with one of the plurality of engagement portions to releasably lock the first buckle portion and the second buckle portion and to define a respective breakaway force. 
     In one example, the plurality of engagement portions are recesses and the corresponding engagement portion is a protrusion arranged to selectively extend at least partly into the respective recess. In another example, the plurality of engagement portions are protrusions and the corresponding engagement portion is a recess, each of the protrusions is arranged to extend at least partly into the recess. 
     Optionally, the first buckle portion comprises a first part and a second part movable relative to the first part, and the plurality of engagement portions are arranged at the second part. 
     Optionally, the second part is rotatable relative to the first part about a rotation axis. 
     Optionally, the rotation axis is generally perpendicular to the breakaway axis. 
     Optionally, the plurality of engagement portions comprise circumferentially spaced grooves defined by circumferentially spaced teeth, and the corresponding engagement portion comprises a projection on a resilient arm. The arm or the projection may be biased radially inwardly. The circumferentially spaced teeth may have different shapes and/or sizes to define circumferentially spaced grooves of different shapes and/or sizes such that different breakaway forces are defined. 
     Optionally, each of the respective teeth and the projection define a respective amount of contact or strength of contact, such that different breakaway forces are defined. 
     Optionally, the plurality of engagement portions comprise a plurality of pairs of circumferentially spaced grooves defined by circumferentially spaced teeth, each pairs of the circumferentially spaced grooves respectively comprises generally-diametrically-opposed first and second grooves; and the corresponding engagement portion comprises generally-diametrically-opposed projection pairs arranged on resilient arms for selectively engaging with each respective pair of the circumferentially spaced grooves. The first and second grooves of the same pair of circumferentially spaced grooves may have substantially the same shape and size. 
     Optionally, each respective pair of the circumferentially spaced teeth and the generally-diametrically-opposed projection pairs define a respective amount of contact or strength of contact, such that different breakaway forces are defined. The circumferentially distributed grooves and teeth may be distributed about the rotation axis 
     Optionally, the rotation axis is generally parallel to the breakaway axis. 
     Optionally, the plurality of engagement portions comprise circumferentially distributed recesses and the corresponding engagement portion comprises a projection on a resilient arm. The circumferentially distributed recesses may be distributed about the rotation axis. The circumferentially distributed recesses may have different shapes and/or sizes. 
     Optionally, each of the circumferentially distributed recesses includes a respective end wall and the projection includes an end face arranged to be in generally-facing relationship selectively with each respective end wall; and each of the end wall extends generally along a respective first axis, the first axes of the end walls are different, the end face extends generally along a second axis, and an acute angle is defined between each respective first axis and the second axis. In one example, the acute angle is limited to between 10 to 80 degrees, between 20 to 70 degrees, between 40 to 70 degrees, etc. The second axis may be generally perpendicular to the breakaway axis. 
     Optionally, the breakaway buckle device further comprises an indicator arranged to provide an indication of a selected breakaway force associated with the first and second buckle portions. The indicator may be provided at the first buckle portion, at the second buckle portion, or partly at the first buckle portion and partly at the second buckle portion. The indicator may be a marker, sticker, etc. The indicator may be stamped, engraved, impressed, integrally formed (e.g., molded), e.g., on the corresponding first and/or second buckle portions. In one example, the indicator is at least partly visible in normal use of the breakaway buckle device. In another example, the indicator is hidden from view in normal use of the breakaway buckle device. 
     The first and second buckle portions may be additively manufactured. For example, the first and second buckle portions may be 3D printed using a 3D printer. The coupling mechanism may be additively manufactured. For example, the coupling mechanism may be 3D printed using a 3D printer. The first and second buckle portions and the coupling mechanism may be additively manufactured together. 
     In one example, the first and second buckle portions together define a face portion shaped to correspond to an outline of at least part of an animal. In one example the face portion is shaped to correspond to an outline of a body of an animal. In one example the face portion is shaped to correspond to the type of pet for which the breakaway buckle device is configured. 
     In a second aspect, there is provided a pet collar comprising the breakaway buckle device of the first aspect. The pet collar may be a cat collar, a dog collar, etc. 
     In a third aspect, there is provided a computer program that, when executed by an additive manufacturing machine, causes the additive manufacturing machine to create the breakaway buckle device of the first aspect. The additive manufacturing machine may be a 3D printer. 
     In a fourth aspect, there is provided a computer model of the breakaway buckle device of the first aspect. The computer model may be a CAD model. 
     In a fifth aspect, there is provided a method of making the breakaway buckle device of the first aspect. The method includes: processing a computer model of the breakaway buckle device using a processor associated with an additive manufacturing machine, and forming the breakaway buckle device of the first aspect using the additive manufacturing machine. The additive manufacturing machine may be a 3D printer. The computer model may be a CAD model. The method may further include creating or providing the computer model of the breakaway buckle device (if not yet created). 
     In a sixth aspect, there is provided a computer program product comprising instructions which, when the program is executed by a processor associated with an additive manufacturing machine, cause the additive manufacturing machine to carry out the method of the fifth aspect. 
     In a seventh aspect, there is provided an additive manufacturing machine, such as a 3D printer, comprising means for carrying out the method of the fifth aspect. 
     In an eighth aspect, there is provided a breakaway buckle device having one or more of the features of the breakaway buckle device of the first aspect. In this eight aspect, the breakaway buckle device may not be arranged for a pet collar but for other articles or applications such as backpacks, harnesses, bags, belts. 
     In a ninth aspect, there is provided a pet collar kit having a breakaway buckle device of the first aspect and one or more straps removably connectable with, or non-removably connected with, the breakaway buckle device. The one or more straps may include multiple straps. The straps may have different lengths, shapes, and/or forms, may be made of different materials, etc. 
     Other features and aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings. Any feature(s) described herein in relation to one aspect or embodiment may be combined with any other feature(s) described herein in relation to any other aspect or embodiment as appropriate and applicable. 
     Terms of degree such that “generally”, “about”, “substantially”, or the like, are, depending on context, used to take into account one or more of: manufacture tolerance, degradation, trend, tendency, imperfect practical condition(s), etc. Unless otherwise specified or implied, the terms “connected”, “coupled”, “mounted” or the like, are intended encompass both direct and indirect connection, coupling, mounting, etc. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings in which: 
         FIG.  1    is a schematic diagram of a pet wearing a pet collar; 
         FIG.  2    is a perspective view of a breakaway buckle device for a pet collar in one embodiment of the invention; 
         FIG.  3    is a part exploded view of the breakaway buckle device of  FIG.  2   ; 
         FIG.  4    is another exploded view of the breakaway buckle device of  FIG.  2   ; 
         FIG.  5 A  is a perspective view of the breakaway buckle device of  FIG.  2    arranged at a first state (defining a first breakaway force); 
         FIG.  5 B  is a sectional view of the breakaway buckle device of  FIG.  5 A ; 
         FIG.  6 A  is a perspective view of the breakaway buckle device of  FIG.  2    arranged at a second state (defining a second breakaway force); 
         FIG.  6 B  is a sectional view of the breakaway buckle device of  FIG.  6 A ; 
         FIG.  7 A  is a perspective view of the breakaway buckle device of  FIG.  2    arranged at a third state (defining a third breakaway force); 
         FIG.  7 B  is a sectional view of the breakaway buckle device of  FIG.  7 A ; 
         FIG.  8    is a perspective view of a pet collar with a breakaway buckle device in one embodiment of the invention; 
         FIG.  9    is a plan view of a breakaway buckle device of the pet collar of  FIG.  8    in one embodiment of the invention; 
         FIG.  10 A  is a sectional view of the breakaway buckle device in the pet collar of  FIG.  9    at a first state (defining a first breakaway force), taken along line I-I in  FIG.  9   ; 
         FIG.  10 B  is a sectional view of the breakaway buckle device in the pet collar of  FIG.  9    at a second state (defining a second breakaway force), taken along line I-I in  FIG.  9   ; 
         FIG.  10 C  is a sectional view of the breakaway buckle device in the pet collar of  FIG.  9    at a third state (defining a third breakaway force), taken along line I-I in  FIG.  9   ; 
         FIG.  11    is a perspective view of a breakaway buckle device for a pet collar in one embodiment of the invention; 
         FIG.  12    is an exploded view of the breakaway buckle device of  FIG.  11   ; 
         FIG.  13    is a cut-away sectional view of a member of the breakaway buckle device of  FIG.  11   ; 
         FIG.  14    is a cut-away sectional view of another member of the breakaway buckle device of  FIG.  11   ; 
         FIG.  15 A  is an exploded view of the breakaway buckle device of  FIG.  11    arranged at a first state (defining a first breakaway force); 
         FIG.  15 B  is a sectional view of the breakaway buckle device of  FIG.  15 A ; 
         FIG.  16 A  is an exploded view of the breakaway buckle device of  FIG.  11    arranged at a second state (defining a second breakaway force); 
         FIG.  16 B  is a sectional view of the breakaway buckle device of  FIG.  16 A ; 
         FIG.  17 A  is an exploded view of the breakaway buckle device of  FIG.  11    arranged at a third state (defining a third breakaway force); 
         FIG.  17 B  is a sectional view of the breakaway buckle device of  FIG.  17 A ; 
         FIG.  18 A  is a perspective view of a breakaway buckle device for a pet collar in one embodiment of the invention; 
         FIG.  18 B  is another perspective view of the breakaway buckle device of  FIG.  18 A ; 
         FIG.  19 A  is a perspective view of a breakaway buckle device for a pet collar in one embodiment of the invention; and 
         FIG.  19 B  is another perspective view of the breakaway buckle device of  FIG.  19 A . 
     
    
    
     DETAILED DESCRIPTION 
       FIG.  1    shows a pet cat  1  wearing on its neck a pet collar  10 . The pet collar  10  includes a strap  12  of material connected with a buckle device  14 . The buckle device  14  can be opened to remove or release the pet collar  10  from the pet&#39;s neck, or closed to wear the pet collar  10  around the pet&#39;s neck. 
       FIGS.  2  to  7 B  show a breakaway buckle device  100  for a pet collar, such as the pet collar  10  in  FIG.  1   , or the one in  FIG.  8    described below, in a first embodiment of the invention. The breakaway buckle device  100  comprises a first buckle portion, a second buckle portion, and a coupling mechanism that is arranged to releasably couple the first buckle portion with the second buckle portion and can be manipulated to adjust a breakaway force required for the first buckle portion to break relatively away from the second buckle portion. 
     Referring to  FIGS.  2  to  4   , the breakaway buckle device  100  includes a first buckle portion  102  and a second buckle portion  152  releasably couplable with each other. The first and second buckle portions  102 ,  152 , when coupled via the coupling mechanism, define a breakaway force. When an external force, in particular separation or tensile force, applied to at least one of the two buckle portions  102 ,  152  along a breakaway axis X reaches or exceeds the breakaway force, the two buckle portions  102 ,  152  will break relative away from and decouple from each other to release or open the collar. 
     The first buckle portion  102  includes a first buckle member  104 , a rotary control member  106 , and a fastener  108 . The rotary control member  106  is mounted to the first buckle member  104  by the fastener  108 . 
     The first buckle member  104  includes a body having a base portion  104 B, an upstanding arcuate side portion  104 A arranged at one side of the base portion  104 B, and an ear portion  104 E extending from the arcuate side portion  104 A away from the base portion  104 B. The base portion  104 B has a generally rounded form, with an upwardly extending tubular guide post  104 G arranged generally centrally on the upper surface of the base portion  104 B. The tubular guide post  104 G elongates along a rotation axis Y. The guide post  104 G has an outer surface arranged to engage with the control member  106  and an inner surface defining a hole arranged to receive the fastener  108 . Three angularly spaced nibs  104 GN are formed on the outer surface of the guide post  104 G and are distributed about the axis Y. The arcuate side portion  104 A has a generally C-shaped cross section in plan view, and includes a radially-inner arcuate portion and a radially-outer arcuate portion which extend around the axis Y for the same angular extent. The height of the outer arcuate portion (as measured upwardly from the upper surface of the base portion  104 B) is higher than that of the inner arcuate portion, thereby defining an arcuate channel  104 C. The top surface of the radially-outer arcuate portion includes, near one end, an indicator or marker  104 I. The ear portion  104 E includes two generally parallel hands joined by a crossbar extending generally perpendicular to the hands. The outer arcuate portion and the ear portion  104 E together define a connector, in the form of a looped portion, for receiving or mounting of a strap (not shown), such as a looped end of the strap. The first buckle member  104  may be integrally formed, e.g., using plastic material(s). 
     The rotary control member  106  includes an upper annular disc portion  106 D and a lower gear portion  106 G with multiple circumferentially spaced gear teeth T 6  of different shapes and/or sizes and corresponding grooves defined between adjacent gear teeth T 1 -T 6 . The gear portion  106 G has a through-hole in communication with and generally coaxial with the hole of the upper annular disc portion  106 D. The through-hole is defined by an inner surface of the lower gear portion  106 G, which is generally circular and has three angularly spaced grooves  106 GG complementary to the nibs  104 GN. The rotary control member  106  can be non-rotatably mounted to the guide post  104 G, with the nibs  104 GN arranged inside the respective grooves  106 GG. The rim  106 R of the disc portion  106 D is roughened or knurled to facilitate grip or manipulation by the user. The top surface of the disc portion  106 D includes three markers, “1”, “2”, “3”, angularly spaced apart by about  120  degrees, which correspond to the positions of different teeth and/or groove of the gear portion  106 G and indicate different extents of breakaway force. The markers “1”, “2”, “3” may be aligned with the marker  104 I to indicate a selected breakaway force.  FIGS.  5 B,  6 B, and  7 B  more clearly illustrate the teeth and/or groove of the gear portion  106 G. As shown in these Figures, the gear portion  106 G includes six circumferentially spaced grooves defined by six circumferentially spaced teeth T 1 -T 6 . More specifically, the grooves are arranged in three pairs, each pairs respectively includes two generally-diametrically-opposed grooves of substantially the same shape and size, and the grooves of different pairs have different shapes and sizes. In this example, the groove between teeth T 1  and T 2  and the groove between teeth T 4  and T 5  form a first pair; the groove between teeth T 2  and T 3  and the groove between teeth T 5  and T 6  form a second pair; the groove between teeth T 3  and T 4  and the groove between teeth T 6  and T 1  form a third pair. The curved wall defining the groove between teeth T 1  and T 2  is longer than the curved wall defining the groove between teeth T 2  and T 3 , which is in turn longer than the curved wall defining the groove between teeth T 3  and T 4 . The rotary control member  106  may be integrally formed, e.g., using plastic material(s). 
     The fastener  108  may be a screw, a bolt, or the like, with a flared or larger cylindrical head  108 H and a relatively narrow cylindrical leg  108 L. The fastener  108  is arranged to be received by the rotary control member  106  and the base portion  104 B, with its flared head  108 H received in the opening defined by the rotary control member  106  and the leg  108 L at least partly received in the hole of the guide post  104 G. The leg  108 L and the hole of the guide post  104 G may include engagement features so that they threadedly engage, friction fit, snap fit, etc. 
     When the first buckle member  104 , the rotary control member  106 , and the fastener  108  are assembled together, the guide post  104 G, the rotary control member  106 , and the fastener  108  are coaxially arranged along the rotation axis Y, and the rotary control member  106  is rotatable relative to the first buckle member  104  and the fastener  108  about the rotation axis Y. The top surface of the fastener  108  is substantially flush with the top surface of the disc portion  106 D of the rotary control member  106 . A peripheral part of the disc portion  106 D is arranged to be received in the arcuate channel  104 C. The disc portion  106 D may be thicker than the arcuate channel  104 C such that the top surface of the disc portion  106 D of the rotary control member  106  is higher than the top surface of the radially-outer arcuate portion and a user may contact at least part of the rim  106 R of the disc portion  106 D to manipulate the rotary control member  106 . In this example, axis Y and axis X are generally perpendicular. 
     The second buckle portion  152  includes a second buckle member  154 . The second buckle member  154  includes a body having an arcuate side portion  154 R, and an ear portion  154 E extending from the arcuate side portion  154 R. The arcuate side portion  154 R has a generally C-shaped cross section in plan view, and includes a radially-inner arcuate portion and a radially-outer arcuate portion which extend for the same angular extent. When the buckle portions  102 ,  152  are coupled, the generally C-shaped arcuate side portion  154 R and the generally C-shaped arcuate side portion  104 A abut each other to together define a space for receiving the rotary control member  106 . The height of the outer arcuate portion is higher than that of the inner arcuate portion, thereby defining an arcuate channel  154 C. The arcuate channel  154 C and the arcuate channel  104 C together define a generally annular channel. The radially-inner arcuate portion defines two arms  154 A with radially-inwardly extending projections  154 P (extending radially-inwardly towards axis Y when the buckle portions  102 ,  152  are coupled) that are generally diametrically opposed. The projections  154 P are arranged to be received in, or engage with, one pair of generally diametrically opposed grooves of the gear portion  106 G. The two arms  154 A are flexible, or resilient, by virtue of their material properties and configuration (e.g., shape, size, etc.) such that they could move radially outwards under the action of a force. The ear portion  154 E includes two generally parallel hands joined by a crossbar extending generally perpendicular to the hands. The outer arcuate portion and the ear portion  154 E together define a connector, in the form of a looped portion, for receiving or mounting of a strap (not shown), such as a looped end of the strap. In this embodiment, the ear portions  104 E,  154 E are arranged at opposite ends of the breakaway buckle device  100 . The second buckle member  154  may be integrally formed, e.g., using plastic material(s). 
     In this embodiment, the top surfaces of the arcuate side portion  104 A, the arcuate side portion  154 R, the rotary control member  106 , and the fastener  108 , together define a face portion shaped, in plan view, to correspond to an outline of a cat face. Also, the breakaway axis X is generally parallel to or coaxial with the long axis (e.g., an axis along a length) of the breakaway buckle device  100 . The teeth T 1 -T 6  (and the associated grooves) of the gear portion  106 G of the rotary control member  106  and the projections  154 P (or more generally the arms  154 A) together define a coupling mechanism. 
     In use, if a user wants to decouple the two buckle portions  102 ,  152  that are coupled with each other, the user first applies a tensile force to these portions  102 ,  152  along the breakaway axis X. The tensile force, if equal to or greater than the breakaway force defined by the two buckle portions  102 ,  152 , will cause the two buckle portions  102 ,  152  to break relatively away from each other. The breakaway is possible because the resilient arms  154 A enable the projections  154 P to move radially outwards and out of the grooves in which they are arranged as the two buckle portions  102 ,  152  move relatively away from each other along the breakaway axis X. In particular, as the tensile force is applied, the trailing wall portion  154 PT of the projection  154 P slides along the wall defining the groove to move radially outwards (due to the resilience of the arm  154 A), and after the trailing wall portion  154 PT clears the wall defining the groove, the projection  154 P is essentially moved out of the groove, and the two buckle portions  102 ,  152  can be separated by applying further separation force. 
     On the other hand, if a user wants to couple the two buckle portions  102 ,  152 , the user first rotates the rotary control member  106  with respect to the radially-outer arcuate portion to select one of the three groove pairs to be engaged with the projections  154 P (hence set a desired breakaway force). The user can perform the selection by rotating the rotary control member  106  about axis Y and aligning one of the markers “1”, “2”, or “3” with the marker  104 I (each of the markers correspond to a respective groove pair). Then, the user applies a compressive force along the axis X to couple the two buckle portions  102 ,  152 . As the two buckle portions  102 ,  152  move relatively towards each other along the axis X, the leading wall portion  154 PL of the projection  154 P slides along the wall of a corresponding tooth to move radially outwards (due to the resilience of the arm  154 A), and after the leading wall portion  154 PL moves past the tooth, the projection  154 P, under the resilience of the arm  154 A, moves radially inwards and drops into the groove between two teeth, optionally producing an audible “click”. In some implementations, the arms  154 A or the projections  154 P are sufficiently flexible such that the rotary control member  106  can be rotated to select the desired breakaway force when the two buckle portions  102 ,  152  are coupled with each other. 
       FIGS.  5 A to  7 B  show the breakaway buckle device  100  being set at three different breakaway forces. 
     In  FIGS.  5 A and  5 B , setting “1” corresponds to the largest breakaway force among the three settings, as the amount of contact between the trailing wall portion  154 PT of the projection  154 P and the corresponding wall portion of the groove (between teeth T 1  and T 2 , or T 4  and T 5 ) is the largest among the three settings, hence a relatively large tensile force is required for the projection  154 P to clear the groove. 
     In  FIGS.  6 A and  6 B , setting “2” corresponds to the medium breakaway force among the three settings, as the amount of contact between the trailing wall portion  154 PT of the projection  154 P and the corresponding wall portion of the groove (between teeth T 1  and T 2 , or T 4  and T 5 ) is medium among the three settings, hence a medium amount of tensile force is required for the projection  154 P to clear the groove. 
     In  FIGS.  7 A and  7 B , setting “3” corresponds to the smallest breakaway force among the three settings, as the amount of contact between the trailing wall portion  154 PT of the projection  154 P and the corresponding wall portion of the groove (between teeth T 1  and T 2 , or T 4  and T 5 ) is the smallest among the three settings, hence a relatively small tensile force is required for the projection  154 P to clear the groove. 
       FIGS.  8  to  10 C  show a breakaway buckle device  200  of a pet collar  20  in a second embodiment of the invention. The breakaway buckle device  200  comprises a first buckle portion, a second buckle portion, and a coupling mechanism that is arranged to releasably couple the first buckle portion with the second buckle portion and can be manipulated to adjust a breakaway force required for the first buckle portion to break relatively away from the second buckle portion. 
     Referring to  FIGS.  8  and  9   , the breakaway buckle device  200  includes a first buckle portion  202  and a second buckle portion  252  each mounted at a respective end of a strap  22 . The two buckle portions  202 ,  252  are releasably couplable with each other. The first and second buckle portions  202 ,  252 , when coupled via the coupling mechanism, define a breakaway force. When an external force, in particular separation or tensile force, applied to at least one of the two buckle portions  202 ,  252  along a breakaway axis I reaches or exceeds the breakaway force, the two buckle portions  202 ,  252  will break relative away from and decouple from each other to release or open the collar  20 . 
     The first buckle portion  202  comprises a first part  202 A and a second part  202 B movably or removably coupled with each other. The second part  202 B includes an ear portion  204 E with two generally parallel hands joined by a crossbar extending generally perpendicular to the hands. The second part  202 B defines, through the ear portion  204 E, a connector, in the form of a looped portion, for mounting the looped end of the strap. The first part  202 A has a generally triangular prism shaped head part, with three faces each having a respective recess defined by wall portions. The recesses of different faces have different shapes, sizes, and/or forms. The first part  202 A can act as a control member, as explained in further detail below. The first part  202 A and the second part  202 B may each be integrally formed, e.g., using plastic material(s). 
     The second buckle portion  252  comprises a second buckle member  254 . The second buckle member  254  includes, at one end, an ear portion  254 E with two generally parallel hands joined by a crossbar extending generally perpendicular to the hands. The second buckle member  254  defines, through the ear portion  254 E, a connector, in the form of a looped portion, for mounting a looped end of the strap. The second buckle member  254  has a generally triangular prism shaped body part, but is hollow, defining an opening for receiving the first part  202 A. One of the faces of the second buckle member  254  includes a cut-out defining a resilient arm  254 A having an inwardly-extending projection  254 P (extending towards the axis I when the buckle portions  202 ,  252  are coupled). The projection  254 P is arranged to be selectively received, at least partly, in one of the recesses on the faces of the first part  202 A, so as to define different breakaway forces, as explained in further detail below with reference to  FIGS.  10 A to  10 C . The second buckle member may be integrally formed, e.g., using plastic material(s). 
     As shown in  FIG.  9   , the second part  202 B and the second buckle portion  252  have complementary size and form. Also, the axis I is the breakaway axis and is generally parallel to or coaxial with the long axis (e.g., an axis along a length) of the breakaway buckle device  100 . 
       FIGS.  10 A to  10 C  are sections taken along line I-I and they illustrate different breakaway forces defined by the buckle portions  202 ,  252 . 
     Referring to  FIG.  10 A , the first part  202 A includes the generally triangular prism shaped head part  202 AH and a leg portion  202 AL. The leg portion  202 AL extends parallel to the axis I from the body part towards the second part  202 B. The leg portion  202 AL has multiple legs, which are resilient, and each of which includes a hooked portion arranged to engage with a correspondingly formed wall part of the opening in the second part  202 B. The leg portion (hence the first part  202 A) thus can movably or removably couple with the second part  202 B to secure the first part  202 A to the second part  202 B. The first part  202 A includes a recess defined by, at least, a slanted wall part  202 AW 1 , a base wall part  202 AB, and another slanted wall part  202 AW 2 . The slanted wall parts  202 AW 1 ,  202 AW 2  are sloped towards different directions with respect to axis I. The base wall part  202 AB is generally parallel to the axis I. The slanted wall part  202 AW 1 , the base wall part  202 AB, and the other slanted wall part  202 AW 2  in the sectional view of  FIG.  10 A  define an inverted acute trapezoid. The arm  254 A of the second buckle member  254  includes a projection  254 P at one end. The projection  254 P includes an end face wall part  254 PW 1  arranged to be in generally-facing relationship with the slanted wall part  202 AW 1 , a base wall part  254 PB arranged generally parallel to the axis I and the base wall part  202 AB and engages with the base wall part  202 AB, and a slanted wall part  254 PW 2  arranged to be in generally-facing relationship with and generally parallel to the slanted wall part  202 AW 2 . The slanted wall part  202 AW 1  extends along a first axis at an angle to the axis I. The end face wall part  254 PW 1  extends along a second axis generally perpendicular to the axis I. The first and second axes define an acute angle. In this example, the slanted wall part  202 AW 1  extends at about 40 degrees with respect to the axis I, while the end face wall part  254 PW 1  extends at about 90 degrees with respect to the axis I. In this embodiment, the recesses (and the associated wall parts) formed on the faces of the first part  202 A of the first buckle portion  202  and the projection  254 P (or more generally the arm  254 A) together define a coupling mechanism. 
     In use, if a user wants to decouple the two buckle portions  202 ,  252  that are coupled with each other, the user first applies a tensile force on these portions  202 ,  252  along the breakaway axis I. The tensile force, if equal to or greater than the breakaway force defined by the two buckle portions  202 ,  252 , will cause the two buckle portions  202 ,  252  to break relatively away from each other. The breakaway is possible because the resilient arm  254 A enables the projection  254 P to move radially outwards (with respect to axis I) and out of the recess (on the face of the first part  202 A) in which it is arranged as the two buckle portions  202 ,  252  move relatively away from each other along the breakaway axis I. In particular, as the tensile force is applied, the slanted wall part  202 AW 1  of the recess slides along the edge of the end face wall part  254 PW 1  to move the projection  254 P radially outwards (due to the resilience of the arm  254 A), and after the slanted wall part  202 AW 1  clears the end face wall part  254 PW 1 , the projection  254 P is essentially moved out of the way, and the two buckle portions  202 ,  252  can be separated by further applying separation force. 
     On the other hand, if a user wants to couple the two buckle portions  202 ,  252 , the user first manipulates (e.g., removes and re-inserts) the first part  202 A to the second part  202 B, to select one of the three recesses to be engaged with the projection  254 P (hence set a desired breakaway force). Then, the user applies a compressive force along the axis Ito couple the two buckle portions  202 ,  252 . As the two buckle portions  202 ,  252  move relatively towards each other along the axis I, the lower end of the leading wall portion  202 AWL of the first part  202 A slides along the slanted wall part  254 PW 2  to move the projection  254 P radially outwards (away from axis I, due to the resilience of the arm  254 A), and after the leading wall portion  202 AWL moves past and clears the slanted wall part  254 PW 2  (and an initial wall section between the leading wall portion  202 AWL and the slanted wall part  202 AW 1 ), the projection  254 P, under the resilience of the arm  254 A, moves radially inwards and drops into the recess on the face of the first part  202 A, optionally producing an audible “click”. 
     The constructions of the device  200  in the configurations of  FIGS.  10 B and  10 C  are the same as those described with reference to  FIG.  10 A , except that the projection  254 P engages with a different recess formed on a different face of the part  202 A. The operation principle in the configurations of  FIGS.  10 B and  10 C  is generally the same as that in  FIG.  10 A . 
     In  FIG.  10 A , the slanted wall part  202 AW 1  is in generally-facing relationship with the end face wall part  254 PW 1  of the projection  254 P, with the slanted wall part  202 AW 1  extending at a first angle (e.g., 40 degrees) with respect to the axis I, thus forming a first gap G 1  between the wall parts  202 AW 1  and  254 PW 1 . This arrangement in  FIG.  10 A  corresponds to the smallest breakaway force among the three settings, as the least tensile force along axis I is required to separate the two buckle portions 
     In  FIG.  10 B , the slanted wall part  202 AW 1 ′ is in generally-facing relationship with the end face wall part  254 PW 1  of the projection  254 P, with the slanted wall part  202 AW 1 ′ extending at a second angle (e.g.,  55  degrees) with respect to the axis I, thus forming a second gap G 2  between the wall parts  202 AW 1 ′ and  254 PW 1 . The second gap G 2  is smaller than the first gap G 1 . This arrangement in  FIG.  10 B  corresponds to a medium breakaway force among the three settings, as a medium tensile force along axis I is required to separate the two buckle portions  202 ,  252 . 
     In  FIG.  10 C , the slanted wall part  202 AW 1 ″ is in generally-facing relationship with the end face wall part  254 PW 1  of the projection  254 P, with the slanted wall part  202 AW 1 ″ extending at a third angle (e.g., 70 degrees) with respect to the axis I, thus forming a third gap G 3  between the wall parts  202 AW 1 ″ and  254 PW 1 . The third gap G 3  is smaller than the second gap G 2 . This arrangement in  FIG.  10 C  corresponds to the largest breakaway force among the three settings, as the most tensile force along axis I is required to separate the two buckle portions  202 ,  252 . 
       FIGS.  11  to  17 B  show a breakaway buckle device  300  for a pet collar, such as the one in  FIG.  1   , or the one in  FIG.  8   , in a third embodiment of the invention. The breakaway buckle device  300  comprises a first buckle portion, a second buckle portion, and a coupling mechanism that is arranged to releasably couple the first buckle portion with the second buckle portion and can be manipulated to adjust a breakaway force required for the first buckle portion to break relatively away from the second buckle portion. 
     Referring to  FIGS.  11  to  14   , the breakaway buckle device  300  includes a first buckle portion  302  and a second buckle portion  352 . The two buckle portions  302 ,  352  are releasably couplable with each other. The first and second buckle portions  302 ,  352 , when coupled via the coupling mechanism, define a breakaway force. When an external force, in particular separation or tensile force, applied to at least one of the two buckle portions  302 ,  352  along a breakaway axis J reaches or exceeds the breakaway force, the two buckle portions  302 ,  352  will break relative away from and decouple from each other to release or open the collar. 
     The first buckle portion  302  comprises a first part  302 A and a second part  302 B movably or removably coupled with each other. In this embodiment the first part  302 A is rotatable relative to the second part  302 B about the axis J, which in this example is also the breakaway axis. The second part  302 B includes a body with an ear portion  302 E with two generally parallel hands joined by a crossbar extending generally perpendicular to the hands. The second part  302 B defines, through the ear portion  302 E, a connector, in the form of a looped portion, for mounting the looped end of the strap. The body of the second part  302 B defines a cavity  302 C for rotatably receiving a leg portion  302 AL of the first part  302 A. The first part  302 A is mushroom-like, with a generally dome-shaped head part  302 AH and a leg portion  302 AL extending from the head part  302 AH. The generally dome-shaped head part  302 AH is arranged to be received in the cavity  352 C defined by the second buckle portion  352  whereas the leg portion  302 AL is arranged to be received in a cavity  302 C defined by the second part  302 B of the first buckle portion  302 . The generally dome-shaped head part  302 AH includes, on its surface, three circumferentially distributed and axially extending recesses  302 AR, e.g., distributed about axis J, and each having, axially adjacent it, a respective marker “1”, “2”, or “3”, for indicating the different selections of breakaway force. The recesses  302 AR have different shapes, sizes, and/or forms. The first part  302 A can act as a control member, as explained in further detail below. The first part  302 A and the second part  302 B may each be integrally formed, e.g., using plastic material(s). 
     The second buckle portion  352  comprises a second buckle member  354 . The body of the second buckle member  354  defines a cavity  352 C for receiving the generally dome-shaped head part  302 AH of the first part  302 A. The body of the second buckle member  354  includes a cut-out defining a resilient arm  354 A having an inwardly-extending projection  354 P (extending towards the axis J when the buckle portions  302 ,  352  are coupled). The projection  354 P is arranged to be selectively received, at least partly, in one of the recesses  302 AR on the surface of the first part  202 A, so as to define different breakaway forces, as explained in further detail below with reference to  FIGS.  15 A to  17 C . The second buckle member  354  may be integrally formed, e.g., using plastic material(s). 
     As shown in  FIGS.  11  and  12   , the second part  302 B of the first buckle portion  302  and the second buckle portion  352  have complementary size and shape. The first part  302 A is substantially enclosed by the second part  302 B of the first buckle portion  302  and the second buckle portion  352 . Also, the axis J is the breakaway axis, as well as the rotation axis of the first part  302 A relative to the second part  302 B, and is generally parallel to or coaxial with the long axis (e.g., an axis along a length) of the breakaway buckle device  300 . 
     Referring to  FIGS.  12 ,  13 ,  15 A, and  15 B , the leg portion  302 AL of the first part  302 A extends parallel to the axis J towards the second part  302 B. The leg portion  302 AL has multiple legs, which are resilient, and each of which includes a hooked portion arranged to engage with a correspondingly formed wall part of the cavity in the second part  302 B. The leg portion (hence the first part  302 A) thus can movably or removably couple with the second part  302 B to secure the first part  302 A to the second part  302 B. In  FIGS.  15 A and  15 B , the first part  302 A includes a recess  302 AR 1  defined by, at least, a slanted wall part  302 AW 1 , a base wall part  302 AB, and another slanted wall part  302 AW 2 . The slanted wall parts  302 AW 1 ,  302 AW 2  are sloped towards different directions. The base wall part  302 AB is generally parallel to the axis J. The arm  354 A of the second buckle member  354  includes a radially-inward projection  354 P (projecting radially inward towards axis J) at one end. The projection  354 P includes a slanted wall part  354 PW 1  arranged to engage with the slanted wall part  302 AW 1 , a base wall part  354 PB arranged generally parallel to the axis J and the base wall part  302 AB and engages with the base wall part  302 AB, and an end face wall part  354 PW 2  arranged to be in generally-facing relationship with the slanted wall part  302 AW 2 . The slanted wall part  302 AW 1  extends generally along a first axis at an angle to the axis J. The end face wall part  354 PW 2  extends along a second axis generally perpendicular to the axis J. The first and second axes define an acute angle. In this embodiment, the recesses (and the associated wall parts) formed on the surface of the first part  302 A of the first buckle portion  302  and the projection  354 P (or more generally the arm  354 A) together define a coupling mechanism. 
     In use, if a user wants to decouple the two buckle portions  302 ,  352  that are coupled with each other, the user first applies a tensile force on these portions  302 ,  352  along the breakaway axis J. The tensile force, if equal to or greater than the breakaway force defined by the two buckle portions  302 ,  352 , will cause the two buckle portions  302 ,  352  to break relatively away from each other. The breakaway is possible because the resilient arm  354 A enables the projection  354 P to move radially outwards (with respect to axis J) and out of the recess  302 AR in which it is arranged as the two buckle portions  302 ,  352  move relatively away from each other along the breakaway axis J. In particular, as the tensile force is applied, the slanted wall part  302 AW 2  of the recess  302 AR slides along the edge of the end face wall part  354 PW 2  to move the projection  354 P radially outwards (due to the resilience of the arm  354 A), and after the slanted wall part  302 AW 2  clears the end face wall part  354 PW 2 , the projection  354 P is essentially moved out of the way, and the two buckle portions  302 ,  352  can be separated by further applying separation force. 
     On the other hand, if a user wants to couple the two buckle portions  302 ,  352 , the user first manipulates (e.g., rotates) the first part  302 A relative to the second part  302 B, to select one of the three recesses to be engaged with the projection  354 P (hence set a desired breakaway force). Then, the user applies a compressive force along the axis J to couple the two buckle portions  302 ,  352 . As the two buckle portions  302 ,  352  move relatively towards each other along the axis J, the tip of the generally dome-shaped head part  302 AH of the first part  302 A slides along the slanted wall part  354 PW 1  to move the projection  354 P radially outwards (away from axis J, due to the resilience of the arm  354 A), and after the tip of the generally dome-shaped head part  302 AH moves past and clears the slanted wall part  354 PW 1 , the projection  354 P, under the resilience of the arm  354 A, moves radially inwards and drops into the selected recess  302 AR 1  of the first part  302 A, optionally producing an audible “click”. 
     The constructions of the device  300  in the configurations of  FIGS.  16 A to  17 B  are the same as those described with reference to  FIGS.  15 A to  15 B , except that the projection  354 P engages with a different recess formed on the surface of the first part  302 A. The operation principle in the configurations of  FIGS.  16 A to  17 B  is generally the same as that in  FIGS.  15 A and  15 B . 
     In  FIGS.  15 A and  15 B , setting “1”, the slanted wall part  302 AW 2  is in generally-facing relationship with the end face wall part  354 PW 2  of the projection  354 P, and the slanted wall part  302 AW 2  extends at a first angle (e.g.,  80  degrees) with respect to the axis J, thus forming a first gap between the wall parts  302 AW 1  and  354 PW 1 . This arrangement in  FIGS.  15 A and  15 B  corresponds to the largest breakaway force among the three settings, as the largest tensile force along axis J is required to separate the two buckle portions  302 ,  352 . 
     In  FIGS.  16 A and  16 B , setting “2”, the slanted wall part  302 AW 2 ′ is in generally-facing relationship with the end face wall part  354 PW 2  of the projection  354 P, and the slanted wall part  302 AW 2 ′ extends at a second angle (e.g., 65 degrees) with respect to the axis J, thus forming a second gap between the wall parts  302 AW 1 ′ and  354 PW 1 . The second angle is smaller than the first angle and the second gap is larger than the first gap. This arrangement in  FIGS.  16 A and  16 B  corresponds to the medium breakaway force among the three settings, as a medium tensile force along axis J is required to separate the two buckle portions  302 ,  352 . 
     In  FIGS.  17 A and  17 B , setting “3”, the slanted wall part  302 AW 2 ″ is in generally-facing relationship with the end face wall part  354 PW 2  of the projection  354 P, and the slanted wall part  302 AW 2 ″ extends at a third angle (e.g., 50 degrees) with respect to the axis J, thus forming a third gap between the wall parts  302 AW 1 ″ and  354 PW 1 . The third angle is smaller than the second angle and the third gap is larger than the second gap. This arrangement in  FIGS.  17 A and  17 B  corresponds to the smallest breakaway force among the three settings, as the least tensile force along axis J is required to separate the two buckle portions  302 ,  352 . 
       FIGS.  18 A and  18 B  show a breakaway buckle device  400  for a pet collar, such as the ones in  FIGS.  1  and  8   , in a fourth embodiment of the invention. The breakaway buckle device  400  comprises a first buckle portion, a second buckle portion, and a coupling mechanism that is arranged to releasably couple the first buckle portion with the second buckle portion and can be manipulated to adjust a breakaway force required for the first buckle portion to break relatively away from the second buckle portion. The breakaway buckle device  400  is similar to the breakaway buckle device  100 . In particular, the coupling mechanism of the breakaway buckle device  400  is the same as the coupling mechanism of the breakaway buckle device  100 . The main difference between the breakaway buckle device  400  and the breakaway buckle device  100  is in the outlook (shape and form). In particular, the breakaway buckle device  400  has a face portion is shaped, in plan view, to correspond to an outline of a fish, not a cat face. 
       FIGS.  19 A and  19 B  show a breakaway buckle device  500  for a pet collar, such as the ones in  FIGS.  1  and  8   , in a fifth embodiment of the invention. The breakaway buckle device  500  comprises a first buckle portion, a second buckle portion, and a coupling mechanism that is arranged to releasably couple the first buckle portion with the second buckle portion and can be manipulated to adjust a breakaway force required for the first buckle portion to break relatively away from the second buckle portion. The breakaway buckle device  500  is similar to the breakaway buckle device  400 . In particular, the coupling mechanism of the breakaway buckle device  500  is the same as the coupling mechanism of the breakaway buckle device  400 . The main difference between the breakaway buckle device  500  and the breakaway buckle device  400  is in the outlook (shape and form). In particular, the rotary control member of the breakaway buckle device  400  and the rotary control member of the breakaway buckle device  500  are arranged in opposite sides or faces of the device. 
     It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the embodiments of the invention as shown to provide other embodiments of the invention. The described embodiments of the invention should therefore be considered in all respects as illustrative and not restrictive. Example optional features of some aspects of the invention are set forth in the summary section above. Some embodiments of the invention may include one or more of these optional features (some of which are not specifically illustrated in the drawings). Some embodiments of the invention may lack one or more of these optional features (some of which are not specifically illustrated in the drawings). One or more features in one embodiment and one or more features in another embodiment may be combined to provide further embodiment(s) of the invention. 
     For example, the breakaway buckle device can be made in a different shape, size, form, and/or color, as appropriate, so long as it includes a first buckle portion, a second buckle portion, and a coupling mechanism arranged to releasably couple the first buckle portion with the second buckle portion and can be manipulated to adjust a breakaway force required for the first buckle portion to break relatively away from the second buckle portion. The adjustment of the breakaway force may be stepped (any number of two or more steps) or stepless. The breakaway axis may be the same as the coupling axis of the two buckle portions. 
     In some embodiments, the breakaway buckle device is additively manufactured using an additive manufacturing machine, e.g., 3D printed using a 3D printer. 
     While the breakaway buckle device embodiments described and/or illustrated herein are for use with a pet collar, it is envisioned that in some instances the breakaway buckle device can be modified and used in other applications (not as part of a pet collar). In one instance, the breakaway buckle device may be arranged around the wrist, the head, the body, the tail, etc. of an animal. In another instance, the breakaway buckle device may be used in backpacks, harnesses, bags, belts, and/or other applications.