Abstract:
Various embodiments of the present disclosure provide a fuel cartridge for a gas-powered fastener-driving tool. In one embodiment, the fuel cartridge comprises a body that has a longitudinal axis and that defines an internal fuel storage cavity. The body is shaped and sized to be inserted at least partially into and removed from a housing defined by a case of the tool via translation along the longitudinal axis. The cartridge also includes a connection and fuel dispensing end fitting connected to the body and sized and shaped to engage an end fitting of the tool within the housing. The cartridge also includes a first cam surface extending at least partially around the longitudinal axis and configured to, during relative rotation of the first cam surface and a second cam surface, engage the second cam surface to facilitate removal of the fuel cartridge from the housing.

Description:
PRIORITY CLAIM 
       [0001]    This patent application claims priority to and the benefit of French Patent Application No. 1562720, which was filed on Dec. 18, 2015, the entire contents of which are incorporated herein by reference. 
       TECHNICAL FIELD 
       [0002]    The present disclosure relates to a fuel cartridge for a gas-powered fixing tool and a gas-powered fixing tool having such a cartridge. 
       BACKGROUND 
       [0003]    The so-called gas-powered fastening or fixing tools are tools having an internal combustion engine operated by the firing of a fuel-air mixture in a combustion chamber, the fuel being injected into the chamber by an injection device from a fuel cartridge. Such tools are intended to drive fastening elements into support materials in order to secure parts. Gas-powered nailers are now very common. As fuel for an internal combustion engine, examples include petrol, alcohol, in liquid and/or gas form. 
         [0004]    Generally speaking, such a tool is portable and comprises a case in which is mounted the internal combustion engine that powers a drive piston of a fastening element. Such a tool may also include a battery power supply and a gripping, handling and firing handle on which a triggering mechanism of the tool is mounted. 
         [0005]    A firing cycle comprises several steps such as the distribution of a quantity of fuel by the cartridge, admission of fuel into the chamber, mixing the fuel with the air in the chamber, ignition and combustion of the mixture to drive the piston, and discharge of combustion gases from the chamber. 
         [0006]    A fuel cartridge conventionally comprises a body comprising an internal fuel storage cavity, and a connection and fuel dispensing end fitting configured to cooperate by interlocking with the abovementioned injection device. 
         [0007]    The body is generally configured to be at least partly engaged in a housing of the tool and to be disengaged by translation along a longitudinal axis of the body. 
         [0008]    The present disclosure proposes to improve this technology. 
       SUMMARY 
       [0009]    The present disclosure proposes a fuel cartridge for a gas-powered fixing tool, comprising a body comprising an internal fuel storage cavity, the body being configured to be engaged at least partly in a housing of the tool and to be disengaged therefrom, by translation along a longitudinal axis of the body, the cartridge comprising, among other things, a connection and fuel dispensing end fitting configured to cooperate with a complementary means of the tool upon the abovementioned engagement of the body, characterized in that the cartridge comprises means for facilitating its disengagement from the housing, the means comprising at least one first cam surface which extends at least partly around the axis. 
         [0010]    The present disclosure thus proposes to facilitate the removal of the cartridge by first means, namely at least a first cam surface, provided on the cartridge. This or each cam surface extends at least partially around the longitudinal axis of body of the cartridge, i.e. that its slope is at least partially oriented around this axis. In certain embodiments, the intersection between a first plane containing the cam surface and by a second plane perpendicular to the aforementioned longitudinal axis and passing through this cam surface, substantially forms a radius of this longitudinal axis. 
         [0011]    The cartridge of the present disclosure may comprise one or more of the following characteristics, taken separately from each other or in combination with each other:
       the at least one cam surface is situated on a crown ring mounted to the cartridge and extending at least partially around the end fitting;   the crown ring comprises two or three cam surfaces regularly distributed around the axis and oriented in the same direction around this axis;   the cam surfaces are situated on a first circumference centered on the axis;   the crown ring comprises at least one hook, and in certain embodiments two or three hooks evenly distributed around the axis, configured to cooperate with a complementary means of the tool;   the hook or the hooks are situated on a second circumference centered on the axis, different from the first circumference;   the crown ring comprises a peripheral edge having an indexing flat or having a radially outer indexing tongue;   the crown ring is formed of a single piece, for example in plastic material, and is mounted, for example force fitted, on the body.       
 
         [0019]    The present disclosure further relates to a gas-powered fixing tool, having a case with a housing configured to receive a fuel cartridge as described above, the tool further comprising at least one second cam surface configured to cooperate with the first cam surface and extending at least partially around a longitudinal axis of the housing. 
         [0020]    The tool according to the present disclosure may comprise one or more of the following characteristics, taken separately from each other or in combination with each other:
       the tool comprises a ring bearing the at least one second cam surface and rotationally mobile around the axis;   the ring is mounted rotationally mobile with respect to a fuel injection member, the member having a complementary means of the end fitting of the cartridge;   the ring is mounted rotationally mobile with respect to the case and comprises a radially outer finger passing through an opening of the case, a free end of the finger being configured to be situated outside the case and accessible by a user in order to disengage the cartridge by rotating the ring in the opening;   the ring comprises two or three second cam surfaces regularly distributed around the axis and oriented in the same direction around this axis;   the second cam surfaces are situated on a first circumference centered on the axis;   the ring comprises at least one hook, and in certain embodiments two or three hooks evenly distributed around the axis, configured to cooperate with a complementary means of the cartridge;   the hook or the hooks are situated on a second circumference centered on the axis, different from the first circumference,   the case comprises, within the housing, indexing and/or guide means configured to cooperate with a complementary means of the cartridge, and   the ring is formed of a single piece, for example in plastic material.       
 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0030]    The present disclosure will be better understood and other details, characteristics and advantages of the present disclosure will become more apparent in light of the following description, given by way of non-limiting example and in reference to the accompanying drawings. 
           [0031]      FIG. 1  is a schematic perspective view of a portion of a gas-powered fixing tool and illustrates a step of inserting or removing a fuel cartridge into a housing of the tool. 
           [0032]      FIG. 2  is another schematic perspective view of the tool part of  FIG. 1 , the fuel cartridge being inserted into the housing of the tool. 
           [0033]      FIG. 3  is a schematic exploded perspective view of the tool part of  FIG. 1 . 
           [0034]      FIG. 4  is a view in a larger scale of a part of  FIG. 3 , and 
           [0035]      FIGS. 5 a  to 5 e    are schematic perspective views of the tool part of  FIG. 1 , with partial cutaway of a case of the tool, and illustrate steps for disengaging the fuel cartridge from the housing of this case. 
       
    
    
     DETAILED DESCRIPTION 
       [0036]    In the description that follows, the terms front, rear, lower, upper, axial, radial, etc., refer to the position of an element relative to an axis and/or in relation to the normal conditions of use of the tool. 
         [0037]    The fixing tool  10  is partially represented in the Figures. This tool comprises a case  12  in which is located an internal combustion engine with a combustion chamber (or a precombustion chamber and a combustion chamber) intended to contain a mixture of air and of fuel, the ignition of which triggers the propulsion of a piston provided to drive a fastening element extracted from a feed magazine, the fastening element intended to be anchored in a support material, at the outlet of a nail guide extending at the front of the case. All these components of gas-powered tools are well known to those skilled in the art and thus have not all been represented in the Figures. 
         [0038]    The combustion chamber of the engine is supplied with fuel by means of an injection member  14 , from a gas fuel cartridge  16  ( FIGS. 1 to 3 ). 
         [0039]    The case  12  of the tool comprises a handle for gripping and handling the tool. The handle is also used for firing, by a triggering mechanism mounted on it. The part of the case  12  represented in the Figures can extend substantially parallel to the handle of the tool, and downstream thereof when the tool is being used. 
         [0040]    In the example shown, the part represented of the case  12  comprises two half-shells that are secured together by screws, for example. Between them, the two half-shells define a first housing  18  for receiving the injection device  14  and a second housing  20  for receiving the cartridge  16  and more exactly a portion thereof. 
         [0041]    The visible part of the case  12  has an elongated shape and the housings  18 ,  20  are arranged one behind the other along the longitudinal axis of the case. The housing  18  is located substantially in the middle of the case  12  and the housing  20  extends between the housing  18  and a longitudinal end of the case  12 . 
         [0042]    The housing  20  has an elongated shape of axis A and comprises a longitudinal end that communicates with the housing  18  and an opposite longitudinal end that opens on the aforementioned longitudinal end of the case, to form an assembly/disassembly opening  22  of the cartridge in the housing  20 . 
         [0043]    As can be better seen in  FIG. 1 , the opening  22  has a general circular or ovoid shape and has a notch  24 , substantially oriented radially relative to the axis A. This notch  24  has a general rectangular shape. 
         [0044]    On its inner surface, each half-shell comprises stiffeners  26  and inner walls  28  ( FIG. 3 ). 
         [0045]    The housing  20  is bounded by lateral internal walls  28   a  substantially parallel to the axis A and by two upper inner walls  28   b  substantially perpendicular to the axis A. First stiffeners  26   a  extend between the walls  28   a,  substantially perpendicular to the axis A, and second stiffeners  26   b  extend between the walls  28   a,  substantially parallel to the axis A. The stiffeners  26   a,    26   b  are shaped to extend in the housing  20  in the continuity of the cross-sectional area defined by the opening  22 . The cross-sectional area thus defined by the stiffeners  26   a,    26   b  of the half-shells is substantially identical to that defined by the opening  22 . It is therefore clear that the stiffeners  26   b  extend in continuation of the lateral edges of the notch  24 . One of the walls  28   a  extends in continuation of the front edge of the notch. The stiffeners  26   b  or the walls  28   a  form the means for guiding the cartridge during its assembly/disassembly, as will be described in more detail in what follows. 
         [0046]    The walls  28   b  are parallel and spaced apart from each other. 
         [0047]    The housing  18  is bounded by internal walls in the example shown, including the walls  28   b,  a rear wall  28   c  substantially parallel to the axis A and an upper wall  28   d  substantially perpendicular to the axis A. The walls  28   b,    28   c  and  28   d  of the half-shells comprise mounting holes in parts of the injection device  14  and of the cartridge  16 . 
         [0048]    The injection device  14  comprises an end fitting  30 , here of the female type, connecting with a male type end fitting on the cartridge  16 , which is not visible in the Figures. 
         [0049]    The end fitting  30  is housed with other elements of the device  14  in the housing  18  and is connected to a supply line  32  from the combustion chamber of the tool. This line  32  has a general S-shape and comprises a straight elongated portion that is housed between the rear walls  28   a  and external walls  34  of the half-shells. The end of the line  32 , opposite the end fitting  30 , is connected to a connecting member  36  to the combustion chamber. This member  36  is mounted in an orifice of the outer walls  34  of the case. The aforementioned elements of the device  14  are also mounted and wedged in the aforementioned orifices of the walls  28   c  and  28   d.    
         [0050]    The end fitting  30 , more visible in  FIG. 4 , comprises a cylindrical body having an inner bore for engaging the end fitting of the cartridge  16 . The lower end of the body of the end fitting, located on the side of the housing  20 , is free to cooperate with the cartridge, and its opposite end is connected to an outer annular flange  38 . 
         [0051]    On its outer periphery, the flange  38  comprises a notch  40  that extends over an angular sector of predetermined angle around the axis A. The aforementioned free end of the body of the end fitting comprises an external annular groove  42 . 
         [0052]    As shown in  FIG. 4 , three parts are mounted on the end fitting  30  of the injection device  14  and are also intended to be received in the housing  18 . These parts include a spring  44 , a ring  46  and a ring  48  that are coaxial and therefore aligned with the axis A. 
         [0053]    The spring  44  comprises at least one metal coil that surrounds the body of the end fitting and is mounted between the flange  38  and the ring  46 . The spring  44  comprises one end bearing on the flange  38  in the circumferential direction and a second end bearing circumferentially on the ring  46 . The first end of the spring  44  here comprises an axial finger  44   a  passing through an orifice of the flange  38  and its second end comprises a radial finger  44   b  cooperating with the ring  46 . This radial finger  44   b  can have its outer radial end  44   c  bent in the circumferential direction, so as be substantially L-shaped ( FIG. 4 ). 
         [0054]    The ring  46  is here formed of a single piece, for example in plastic material. It surrounds the body of the end fitting  30  and is held axially on the latter by means of the ring  48 , which is a split lock ring intended to be mounted in the groove  42  of body of the end fitting  30 . 
         [0055]    The ring  46  is mounted rotationally mobile on the body of the end fitting  30 , around the axis A. It is guided in rotation by the two walls  28   b  of the case. 
         [0056]    In the example shown, the ring  46  comprises two cylindrical walls, internal  46   a  and external  46   b,  respectively, extending one around the other. 
         [0057]    The inner wall  46   a  is slidably mounted on the body of the end fitting  30 . The upper peripheral edge of the outer wall  46   b,  located on the opposite side of the housing  20 , comprises a tongue  60  projecting parallel to the axis A. This tongue  60  is intended to be engaged in the notch  40  of the flange  38  and to cooperate by abutment with the circumferential ends of this notch  40  to the angular travel of the ring  46  with respect to of the end fitting  30  around the axis A. The radial finger  44   b  of the spring  44  bears circumferentially on this tongue  60  to solicit it in the circumferential direction toward a circumferential end of the notch  40 . The bent end of the finger  44  can extend around the tongue  60  and may be used to pinch the tongue and thus ensure an attachment of these two elements. The spring  44  can be mounted preloaded circumferentially between the end fitting  30  and the ring  48 . 
         [0058]    The outer wall  46   b  of the ring  46  further comprises a finger  62  extending radially outwardly relative to the axis A. This finger  62  is intended to pass through an opening  64  of one of the half-shells of the case  12  ( FIGS. 1 and 2 ). The outer radial end of the finger  62  is free and intended to be accessible by a user to be moved in the opening  64 , which has an elongated shape and extends around the axis A. The opening  64  extends over an angular sector of angle substantially equivalent to that of the notch  40 . 
         [0059]    It is therefore clear that the movement of the finger  62  in the opening will drive the ring  46  in a rotational movement about the end fitting  30 , and the tongue  60  in the notch  40 . The ring  46  is movable from a first position, wherein the tongue  60  and the finger  62  are located in the first circumferential ends of the notch  40  and the opening  64  ( FIG. 5 a   ), respectfully, to a second position wherein the tongue  60  and the finger  62  are located in second circumferential ends opposite the notch  40  and the opening  64  ( FIG. 5 d   ), respectively. The first position is a rest position wherein the spring  44  holds the tongue  60  in the aforementioned position, and the second position is a position imposed by the user by applying a force on the finger  62 , to overcome the return force of the spring. 
         [0060]    The lower peripheral edge of the outer wall  46   b,  located on the side of housing  20 , comprises arrangements or recesses defining cam surfaces  66 , three in this case. The cam surfaces  66  are regularly distributed around the axis A. They are at least partly oriented around the axis A. In other words, the intersection between a first plane containing the cam surface and a second plane perpendicular to the axis A and passing through this cam surface, substantially forms a radius of the axis A. 
         [0061]    In the example shown, each cam surface  66  has a longitudinal dimension or height along the axis, which represents 10 to 50% of that of the outer wall  46   b  or the ring  46 . Its circumferential dimension or length around the axis extends over an angular sector between approximately 2 and 10°. 
         [0062]    Each cam surface  66  is connected at one end to the lower peripheral edge of the wall  46   b,  and at an opposite end to one end of a circumferential end  68  whose opposite end is connected to an axial connecting edge  70  to the lower peripheral edge of the wall  46   b.  The angular sector extending between the axial edge  70  and the end of the cam surface  66 , opposite this axial edge, has an angle that is less than that of the notch  40  and of the opening  64 . 
         [0063]    Between its walls  46   a,    46   b,  the ring  46  comprises hooks  72  oriented circumferentially with respect to the axis A. The hooks  72  are uniformly distributed about the axis A. It is understood that the hooks  72  are located on a circumference C 2  different from the circumference C 1  passing through the cam surfaces  66 , C 2  having a radius smaller than C 1 . 
         [0064]    The fuel cartridge  16  will now be described. 
         [0065]    The cartridge  16  comprises a body  74 , substantially cylindrical here, comprising an internal fuel storage cavity, and the aforementioned end full connection and distribution end fitting, that is configured to cooperate by interlocking with the end fitting  30  of the device  14  and that is not visible in the Figures. 
         [0066]    The body  74  is configured to be engaged, here in part, in the housing  20  of the case  12  and to be disengaged, by translation along the axis A, which is the longitudinal axis of the body when the cartridge is aligned on the axis A, as shown in  FIG. 1 . 
         [0067]    The cartridge  16  further bears a crown ring  76  around its connection end fitting. Here, this crown ring  76  is formed of a single piece, for example in plastic material, and can be force fitted on the body  74 . The cartridge  16  equipped with the crown ring  76  can represent a consumable of the tool  10 . 
         [0068]    The crown ring  76  comprises a cylindrical wall  76   a  of axis A and a radial annular wall  76   b  that here bears axially on an outer peripheral edge of the upper end of the body  74  of the cartridge ( FIG. 4 ). 
         [0069]    The radial wall  76   b  comprises a flat section or a tongue  78  projecting radially, which is substantially complementary to the notch  24  of the opening  22  of the case. The tongue  78  and notch  24  form indexing means to ensure proper angular positioning of the cartridge  16  about the axis A when inserted into the housing  20 . It is understood that this tongue  78  is intended to cooperate with the stiffeners  26   b  and the front side wall  28   a  of the case in order to guide the translation of the cartridge along the axis A in the housing  20 . 
         [0070]    The cylindrical wall  76   a  is intended to cooperate by axial sliding and circumferential with the inner wall  46   b  of the ring. It is intended to extend around the wall  46   b,  between it and the hooks of the ring  46 . 
         [0071]    The crown ring  76  comprises projecting studs on the upper surface of its wall  76   b,  that define cam surfaces  80 , three in this case. The cam surfaces  80  are regularly distributed around the axis A. They are at least partly oriented around the axis A. In other words, the intersection between a first plane containing the cam surface and a second plane perpendicular to the axis A and passing through this cam surface, substantially forms a radius of the axis A. 
         [0072]    In the example shown, each cam surface  80  has a longitudinal dimension or height substantially identical to that of the cam surfaces  66 . Its circumferential dimension or length around the axis is substantially identical to that of the cam surfaces  66 . 
         [0073]    Between the wall  76   a  and the cam surfaces  80 , the crown ring  76  comprises hooks  82  oriented circumferentially with respect to the axis A. The hooks  82  are uniformly distributed around the axis A and are intended to cooperate with the hooks  72  of the ring  46 . It is understood that the hooks  82  are located on a circumference C 2  different from the circumference C 1  passing through the cam surfaces  80 , C 2  having a radius smaller than C 1 . Each hook  82  here has a general L-shape and comprises an axial portion connected to a circumferential portion. This circumferential portion comprises an upper cam surface  82   a  intended to cooperate with a lower cam surface of a hook  72 , which may also have a general L-shape. 
         [0074]    The cartridge  16  can be mounted or inserted in the housing  20  in the following manner. 
         [0075]    The cartridge  16  is presented at the entrance of housing  20 , i.e. opposite the opening  22 , and aligned on the axis A as shown in  FIG. 1 , its upper end having the connection end fitting and the crown ring  76  intended to be inserted first into the housing  20 . 
         [0076]    The indexing tongue  78  cooperates with the notch  24  in order to correctly position the cartridge  16  with respect to the entrance of the housing  20 . 
         [0077]    The cartridge  16  is moved in translation along the axis A until its end fitting fits into the end fitting  30  of the injection device  14 . In this nested position, a lower end part of the cartridge  16  remains outside the case as shown in  FIG. 2 , to facilitate its removal for replacement, for example. 
         [0078]    When the end pieces are engaged, the cam surfaces of the hooks  72 ,  82  cooperate together so that the insertion force applied by a user on the cartridge generates a rotation of the ring  46  around the axis A. During this rotation, the studs of the crown ring  76  move into the emplacements of the ring  46  and pass, for example, from the position shown in  FIG. 5 a    to the position shown in  FIG. 5 b   . After the sliding of the cam surfaces of the hooks  72 ,  82  on one another, maintaining the insertion force on the cartridge enables the circumferential parts of the hooks  82  of the crown ring to extend axially past those of the hooks  72  of the ring  46 . The spring  44  then ensures an elastic return of the ring  46  to its rest position, which ensures the engagement of the hooks  72  of the ring in those  82  of the crown ring. During this elastic return, the studs of the crown ring  76  move into the emplacements of the ring  46  and pass, for example, from the position shown in  FIG. 5 b    to the position shown in  FIG. 5 a   . The cartridge  16  is then locked and the tool  10  can be used. 
         [0079]    The cartridge  16  can be removed or disengaged from the housing  20  in the following manner. 
         [0080]    The user applies a force on the finger  62  to move it from its rest position shown in  FIG. 2  to its opposite position shown in  FIG. 1 . The rotation of the finger  62  is carried out in several sub-steps that are illustrated by  FIGS. 5 a    to  5   e.    
         [0081]      FIG. 5 a   , with  FIG. 2 , represent the cartridge  16  and the ring  46  in the operating position. In this position, the studs of the crown ring  76  are located in the emplacements of the ring  46  and are at a circumferential distance from the cam surfaces of the ring  46 . 
         [0082]      FIG. 5 b    represents the case where the finger  62  has been moved over part of its stroke in the opening of the case, to the point where the cam surfaces  66 ,  80  are in contact with one another or immediately adjacent to each other. This movement enables the hooks  72 ,  82  to disengage from each other, thereby unlocking the cartridge  16 . 
         [0083]      FIG. 5 c    shows the case where the finger  62  is moved further in the opening  64 . The cam surfaces  66 ,  80  cooperate with each other so that the rotation of the ring  46  drives a translational movement of the cartridge  16  along the axis A and the disengagement of the end fittings. 
         [0084]      FIG. 5 d    represents the case where the finger  62  has reached the end of its travel in the opening  64 . The cam surfaces  66 ,  80  have finished cooperating together and the end fittings are disengaged from each other. 
         [0085]    The cartridge  16  can then be manually removed by the user without difficulty, in a translational movement along the axis A ( FIG. 5 e   ). 
         [0086]    In an alternative embodiment of the present disclosure not represented, the ring (mobile) could be borne by the cartridge and the crown ring (fixed) could be borne by the case of the tool.