Abstract:
A connecting module is provided with a first connecting component, which has a first fluid channel and a first contact surface, a second connecting component, which has a second fluid channel and a second contact surface. One of the two contact surfaces is formed as an inner surface and the other of the two contact surfaces is formed as an outer surface which is complementary to the inner surface. The connecting module further includes a receiving sleeve with a first threaded section and a first connecting device for the first connecting component. The first connecting component has a second connecting device, which interacts with the first connecting device in such a way that the first connecting component is detachably connected to the receiving sleeve. The second connecting component has a second threaded section which is complementary to the first threaded section.

Description:
PRIORITY 
     This application claims priority to German Patent Application No. 102014201392.5, filed on Jan. 27, 2014, which is hereby incorporated herein by reference in its entirety. 
     FIELD 
     The present invention relates to a connecting module with a first connecting component, which has a first fluid channel and a first contact surface, and a second connecting component, which has a second fluid channel and a second contact surface. Such connecting modules can be formed e.g. as a Luer lock connection and are used, for example, for medical applications, wherein the first connecting component can be a cannula or a tube and the second connecting component can be, for example, part of a syringe. The present invention further relates to a syringe with such a connecting module. 
     BACKGROUND 
     When using conventional connecting modules a difficulty often exists that it is difficult to release the connection. If the first connecting component is formed as a cannula, there is always a risk of injury. In particular, the cannula can be contaminated, which leads to a risk of infection. 
     SUMMARY 
     An object of the invention includes a connecting module described at the beginning in such a way that it is possible to release the connection safely. The object can be achieved by providing a connecting module, which comprises a first connecting component, which has a first fluid channel and a first contact surface, and a second connecting component, which has a second fluid channel and a second contact surface, wherein one of the two contact surfaces is formed as an inner surface and the other of the two contact surfaces is formed as an outer surface which is complementary to the inner surface, wherein the connecting module further comprises a receiving sleeve with a first threaded section and a first connecting device for the first connecting component, the first connecting component has a second connecting device, which interacts with the first connecting device in such a way that the first connecting component is detachably connected to the receiving sleeve, wherein the second connecting component has a second threaded section which is complementary to the first threaded section and, by screwing the two threaded sections, the two fluid channels are connected to each other and the first contact surface of the first connecting component is brought into contact in a sealing manner with the second contact surface of the second connecting component, and wherein on unscrewing the two threaded sections, the receiving sleeve exerts a force via the two connecting devices to the first connecting component which moves the first contact surface away from the second contact surface. 
     With the connecting module according to certain embodiments of the invention it is therefore possible easily to release the connection. It is only necessary to unscrew the connection and this can be carried out by actuating the receiving sleeve with the result that the first connecting component, which can be e.g. a cannula, does not have to be handled. 
     One of the two connecting devices can have a retaining groove and the other of the two connecting devices can have a projection which, in the screwed-in state, projects into the retaining groove. 
     The receiving sleeve can have a through hole with an inner wall, wherein the first connecting device has the retaining groove which is formed in the inner wall. 
     The second connecting device can have two, three, four or more projections spaced apart from each another, which project in each case in a direction radial to the first filling channel. 
     The receiving sleeve can further have a recess at its first end facing away from the connecting component for each projection, which recess extends from the first end to the retaining groove, with the result that the cannula can be inserted via the recess into the retaining groove. 
     One of the two contact surfaces can be formed as an inner tapered surface (or as an inner conical surface) and the other of the two contact surfaces can be formed as an outer tapered surface (or as an outer conical surface). 
     The cannula can have a base section on which the first connecting device is formed. In one example, the connection can be formed as a Luer lock connection. 
     The receiving sleeve can be formed as a receiving nut in which the first threaded section is an internal threaded section. 
     Furthermore, a syringe is disclosed. The syringe includes a base body, which has a syringe cylinder with an expelling side end, and a plunger rod, the front end section of which is arranged to be displaceable in the syringe cylinder along a displacement direction, in which a connecting module according to the invention is provided, wherein the second connecting component is part of the base body or is connected to this and the second fluid channel is in fluid connection with the syringe cylinder. 
     In certain embodiments of the syringe, the base body can include a front stop for the plunger rod in the case of which the distance between the front end section and the expelling side end of the syringe cylinder is minimal. In addition, the syringe can comprise a setting element which has a rear stop for the plunger rod in the case of which the distance between the front end section and the expelling side end of the syringe cylinder is maximal, wherein the setting element is movable relative to the base body and can be detachably connected to the base body in at least two predetermined setting positions in which the position of the rear stop is different in the displacement direction, with the result that, by choosing one of the setting positions for the setting element, the maximum travel of the plunger rod can be set. 
     With the syringe according to certain embodiment of the invention, the maximum travel of the plunger rod and thus the amount to be expelled can therefore be set easily. The set amount to be expelled can thus be repeatedly administered safely. 
     The syringe can be formed as a self-refilling syringe. By a self-refilling syringe is, in particular, meant a syringe in which the fluid (e.g. medicament) to be administered is filled into the syringe cylinder in the case of a movement of the plunger rod from the front stop to the rear stop and is expelled from the syringe cylinder via the expelling side end in the case of the opposite movement from the rear stop to the front stop. 
     The setting element can be movable relative to the base body along the displacement direction. For example, the setting element can be formed as a hollow cylinder with a base, wherein the base forms the rear stop. 
     The base can have a through hole for the plunger rod. The plunger rod can have a lateral projection (e.g. annular) which rests on an inner side of the base when the plunger rod is at the rear stop. The contact between the projection and the inner side of the base thus forms the rear stop. 
     The plunger rod can be made in one piece or also several pieces. The region of the plunger rod which moves to and fro in the syringe cylinder can also be referred to as a plunger or plunger section. 
     The setting element can have a spring-loaded pressure piece and the base body can have, in each predetermined setting position, a catch recess for the spring-loaded pressure piece. For example, the base body can have a guide groove or a guide slot for the spring-loaded pressure piece, wherein the guide groove or slot extends along the displacement direction and guides the spring-loaded pressure piece along the displacement direction when the setting element is displaced relative to the base body. 
     In the syringe according to certain embodiment of the invention, an adjusting groove (or adjusting slot) can, for each predetermined setting position, branch off from the guide groove transverse with respect to the guide groove into which adjusting groove the spring-loaded pressure piece can be brought by means of a relative rotation of the setting element and base body. In particular, each adjusting groove has a catch recess with the result that the desired arrest is produced in interaction with the spring-loaded pressure piece. This arrest can be released by rotation in the opposite direction if the force used is so large that the spring-loaded pressure piece is released from the catch recess. 
     In the place of a spring-loaded pressure piece, other fixing elements are also possible. For example, jamming can be carried out by a screw which is guided into the setting element and presses against the base body. 
     In the syringe according to certain embodiment of the invention, the position of the front stop can be fixed. This is very advantageous in particular when formed as a self-refilling syringe since it is possible to fill the syringe cylinder via the expelling side end and all of the fluid can always be expelled from the syringe cylinder. 
     The syringe can also be described as an injection device and/or an injection system. Further elements which are necessary for the operation of such an injection system are known to a person skilled in the art and can be provided. In particular, the plunger rod can be driven e.g. pneumatically by a compressed air cylinder. For this, the end of the plunger rod facing away from the syringe cylinder can be mechanically connected to the compressed air cylinder. 
     The syringe can include a cannula which is in fluid connection with the expelling side end of the syringe cylinder such that the fluid can be administered from the syringe cylinder via the cannula. The cannula can be fixed on the base body detachably. For example, the detachable connection can be formed in such a way that the cannula does not have to be handled to be detached. 
     The cannula can have a first fluid channel and a first contact surface. Furthermore, the base body of the syringe can have a connecting component with a second fluid channel and a second contact surface. The connecting component can be formed by a section of the base body itself or as a separate component connected to the base body. 
     It is understood that the features mentioned above and those yet to be explained below can be used not only in the stated combinations, but also in other combinations or alone, without departing from the scope of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is explained in further detail below by way of example with reference to the attached drawings which also disclose features essential to the invention. 
         FIG. 1  is a perspective view of a first embodiment of the syringe according to certain embodiments. 
         FIG. 2  is a perspective exploded representation of the syringe of  FIG. 1 . 
         FIG. 3  is a sectional representation according to the section line A-A in  FIG. 2 . 
         FIG. 4  is a longitudinal sectional representation of the syringe according to certain embodiments in which the rear stop is in a first predetermined setting position. 
         FIG. 5  is a sectional representation according to  FIG. 4  in which the rear stop is in a second predetermined setting position. 
         FIG. 6  is a sectional representation according to  FIG. 5  of a modification of the syringe according to certain embodiments. 
         FIG. 7  is a top view of the nut of the syringe according to certain embodiments. 
         FIG. 8  is a sectional view of the receiving nut along the section line B-B in  FIG. 7 . 
         FIG. 9  is a sectional view of the receiving nut along the section line C-C in  FIG. 7 . 
         FIG. 10  is a top view of the cannula according to certain embodiments. 
         FIG. 11  is an enlarged sectional representation of the cannula, the receiving nut and the adapter of the syringe according to certain embodiments. 
         FIG. 12  is a sectional view according to  FIG. 11 , wherein the cannula is rotated about its longitudinal axis by 90° vis-à-vis the position according to  FIG. 11 . 
     
    
    
     DETAILED DESCRIPTION 
     The present invention can be explained with reference to the following example embodiments. However, these example embodiments are not intended to limit the present invention to any specific examples, embodiments, environments, applications or implementations described in these embodiments. Therefore, description of these embodiments is only for purpose of illustration rather than to limit the present invention. 
     In the embodiment shown in  FIGS. 1-5 , the syringe  1  according to the invention comprises a base body  2  in which a syringe cylinder  3  with an expelling side end  4  ( FIGS. 4 and 5 ) is formed. The syringe  1  comprises a plunger rod  5 , the front end section  6  of which is arranged to be displaceable in the syringe cylinder  3  along a displacement direction P 1  (in  FIGS. 5 and 6  from left to right). 
     The expelling side end  4  of the syringe cylinder  3  opens out into the base body  2  in a T-shaped channel section  7 , in the ends of which are not connected to the expelling side end  4  are arranged a first and second non-return valve  8 ,  9 . The first non-return valve  8  is formed in such a way that, in the case of the plunger rod  5  being drawn back (i.e. a movement from left to right in  FIGS. 4 and 5 ) a fluid, such as e.g. a medicament to be administered, flows or is sucked via a fluid connection  10  and the first non-return valve  8  into the syringe cylinder  3 . The fluid can in particular be a liquid. The second non-return valve  9  is formed in such a way that, in the case of an opposite movement of the plunger rod  5  (i.e. from right to left in  FIGS. 4 and 5 ), the fluid located in the syringe cylinder  3  is expelled via the second non-return valve  9  into a channel  11  of an adapter  12  and from the latter through a cannula  13  connected to the adapter  12 . 
     The adapter  12  and the cannula  13  together with a receiving nut form a connecting module, which is described in more detail below in conjunction with  FIGS. 7-12 . First of all, however, other elements of the syringe  1  are first described. 
     The syringe  1  is formed in such a way that the maximum travel of the plunger rod  5  and thus the amount of fluid to be dispensed can be set. For this, the base body  2  has a front stop  15  for the plunger rod  5 , which front stop is formed by shoulders  16  at the expelling side end  4  of the syringe cylinder  3 . The shoulders  16  are formed in that the diameter of the syringe cylinder  3  is larger than the diameter of the adjacent part of the channel of the T-shaped channel section  7 . 
     The front end section  6  of the plunger rod  5  has, at its front end  17 , an annular stop surface  18 , which rests on the shoulders  16  when the front end section  6  is pushed completely into the syringe cylinder  3 . In the embodiment described here, the front end  17  also has a cylindrical projection  19  which then projects into the corresponding part of the T-shaped channel section  7 . In an alternative embodiment (not shown), the projection  19  is not provided, with the result that the front end  17  can be formed e.g. planar and has the annular stop surface  18  in its outer region. Furthermore, in the area of the front end section  6 , the plunger rod  5  has a sealing ring  14  which sits in a corresponding annular groove. When the annular stop surface  18  rests on the shoulders  16 , the distance between the front end  17  and the expelling side end  4  is minimal. 
     The syringe  1  further has a sleeve-shaped setting element  20  which defines a rear stop  21  for the plunger rod  5  in the case of which the distance between the front end  17  and the expelling side end  4  of the syringe cylinder  3  is maximal. For this, a through hole  23 , through which the plunger rod  5  runs, is formed in the base  22  of the setting element  20  which has a U-shaped cross-section. In the embodiment described here, inserted in the through hole  23  is a guide sleeve  24 , which defines an opening in the base  22  which is coaxial with the syringe cylinder  3  and has a smaller diameter than the syringe cylinder  3 . 
     The plunger rod  5  is formed in such a way that the front end section  6  has an external diameter which is adapted to the syringe cylinder  3  and thus serves as a plunger. A rear section  25  of the plunger rod  5 , which has a smaller diameter than the front end section  6 , is attached to the front end section  6 . The diameter of the rear section  25  is adapted to the opening defined by the guide sleeve  24 . Furthermore, the front end section  6  has, on its end facing away from the front end  17  to which the rear section  25  of the plunger rod  3  is attached, a substantially annular projection  26  which, in the cross-sectional representations according to  FIGS. 4 and 5  rests on an inner side  27  of the base  22 . The inner side  27  thus forms the rear stop  21  for the plunger rod  5  since it is not possible to pull the plunger rod  5  out of the syringe cylinder  3  beyond this position. 
     The setting element  20  is, as is described below in detail, displaceable relative to the base body  2  in the displacement direction P 1  of the plunger rod  5  and can be fixed or arrested at predetermined setting positions to the base body  2  with the result that, by this means, the position of the rear stop  21  can be set and altered in the displacement direction P 1 . In the syringe  1  according to the invention, the front stop  15  is fixed, or its position cannot be altered, while the rear stop  21  can be adjusted. By setting the position of the rear stop  21  in this way, the maximum travel of the plunger rod  5  and thus the maximum amount of fluid which can be expelled with a single movement of the plunger rod (displacing the plunger rod  5  from its rear stop position to its front stop position) are determined. 
     As can be seen in  FIGS. 4 and 5 , the setting element  20  has, in the region of its front open end  30 , a spring-loaded pressure piece  31  and a pin  32 , which extend in each case in the radial direction and are arranged opposite each other. The spring-loaded pressure piece  31  has, on its end projecting inwards, a ball  28  which is loaded by means of a spring, which is not shown, with a force in the direction to the syringe cylinder  3  and serves to arrest the setting element  20 . The pin  32  and the spring-loaded pressure piece  31  are arranged in the front open end  30  in such a way that they project inwards beyond an inner wall of the setting element  20 . The diameter of the inner wall of the setting element  20  corresponds to the external diameter of the base body  2  in its rear end section  33  in which the syringe cylinder  3  is formed. In order to make it possible to displace the setting element  20  relative to the base body  2  or on the rear end section  33  of the base body  2 , both for the spring-loaded pressure piece  31  and also for the pin  32 , a guide groove  34 ,  34 ′ extending in the displacement direction is formed on the outer side of the rear end section  33 . The guide groove  34  for the spring-loaded pressure piece  31  can be seen in the perspective exploded representation according to  FIG. 2 . Both guide grooves  34 ,  34 ′ are visible in the sectional representation in  FIG. 3  (cut along A-A in  FIG. 2 ). Four adjusting grooves  35 ,  35 ′ go off in each case from the guide groove  34  as well as from the guide groove  34 ′, which adjusting grooves extend in each case in the circumferential direction of the rear end section  33  along a predetermined angle range. The adjusting grooves  35  for the spring-loaded pressure piece  31  each end in a catch recess  36 . In the embodiment example described here, two of the four adjusting grooves  35  extend clockwise and the other two adjusting grooves  35  extend anticlockwise. The same applies to the adjusting grooves  35 ′. In the displacement direction (double arrow P 1  in  FIGS. 2, 4 and 5 ), the four adjusting grooves  35  and the four adjusting grooves  35 ′ are each spaced apart from each other such that four predetermined setting positions are available. However, the guide groove  34 ′ for the pin  32  and the corresponding adjusting grooves  35 ′, which are not visible in  FIG. 2 , have a smaller width due to the smaller diameter of the pin  32  compared with the spring-loaded pressure piece  31 . Furthermore, the adjusting grooves  35 ′ for the pin  32  do not end in a catch recess. 
     In the sectional view according to  FIG. 3  an adjusting groove  35  is shown which ends with a catch recess  36 . The corresponding adjusting groove  35 ′ for the pin  32  ends without a catch recess. 
     In order to set a desired maximum travel of the plunger rod, starting from the exploded representation in  FIG. 2  the setting element  20  is to be turned anticlockwise (direction of rotation according to arrow P 2  in  FIG. 2 ) by 90°, with the result that the end (with the ball  28 ) of the spring-loaded pressure piece  31  projecting inwards can be moved along the guide groove  34 . The setting element  20  is then to be moved along the displacement direction P 1  such that the spring-loaded pressure piece  31  is at the level of the desired adjusting groove  35  and the setting element  20  is then arrested by rotating it in the direction of the catch recess  36  of the chosen adjusting groove  35  (i.e. either clockwise or anticlockwise), since on reaching the catch recess  36 , the ball  28  of the spring-loaded pressure piece  31  is pressed into the catch recess  36 . 
     The maximum travel of the plunger rod according to the invention can thus be set. The syringe  1  therefore has different catch positions for the rear stop  21 . 
     In the embodiment described here, the plunger rod  5  is driven pneumatically by a compressed air cylinder which is not shown. The corresponding connection can be made with the end  38 , facing away from the base body  2 , of the rear section  25  of the plunger rod  5 . In the embodiment described, an external thread is formed at the end  38  of the plunger rod  5 . 
     In  FIG. 6  a sectional view according to  FIGS. 4 and 5  is shown in a modification of the syringe  1  according to the invention. The syringe  1  according to  FIG. 6  differs from the syringe  1  described hitherto in that instead of the pin  32  a second spring-loaded pressure piece  40  is provided. The corresponding guide groove  34 ′ and the corresponding adjusting grooves  35 ′ are therefore formed in the same way as for the spring-loaded pressure piece  31  of the embodiment described hitherto. In particular, the adjusting grooves  35 ′ for the second spring-loaded pressure piece  40  each have a catch recess. The rest of the design of the syringe  1  according to  FIG. 6  corresponds to the design of the syringe of  FIGS. 1 to 5  such that identical elements are given identical reference symbols and for the description thereof reference is made to the above statements. 
     In the embodiments according to  FIGS. 1 to 6 , the cannula  13  is detachably attached to the adapter  12 , wherein the adapter  12  is detachably connected (via a screw connection) to the base body  2 . The connection between cannula  13  and adapter  12  is described below in conjunction with  FIGS. 7-12  and is formed as a so-called Luer lock connection, wherein the adapter  12  has, on its end facing away from the syringe cylinder  3 , an outer tapered section  50  on which sits a corresponding inner tapered section  51  of a base  52  of the cannula  13 . An annular projection  49  of the base  52  of the cannula  13  sits in an annular retaining groove  53  of a receiving nut  54  which is screwed onto the adapter  12 . For this, the receiving nut  54  has an internal threaded section  55  and a corresponding external threaded section  56  is formed on the adapter  12 . 
     As can be seen in particular from the top view of the cannula  13  in  FIG. 10 , the outline of the annular projection  49  of the foot  52  is substantially circular and has two opposite lateral projections  57 ,  58 , with the result that thereby a deviation from the circular shape is present. 
     The retaining groove  53  is formed on an inner side of a through hole  59  in the base  60  of the receiving nut  54  of substantially U-shaped cross-section ( FIGS. 8, 9, 11, 12 ). The region of the through hole  59 , which runs from the front end  65  of the receiving nut  54  facing away from the adapter  12  to the retaining groove  53 , has, in cross-section, an outline which corresponds to the outline of the annular projection  49  of the cannula  13 . As can be seen in particular in the top view of  FIG. 7 , the outline of the through hole  59  is substantially circular and has two recesses  61 ,  62  projecting radially outwards. However, these recesses  61  and  62  of the through hole  59  only extend from the front end  65  to the retaining groove  53 . In the region from the retaining groove  53  to the inner side  63  of the base  60  facing the adapter  12  the recesses  61  and  62  are not formed with the result that here the through hole  59  only has a circular cross-sectional shape. 
     The through hole  59  with the recesses  61  and  62  is formed such that the annular projection  49  of the cannula  13  can be inserted from the front end  65  of the receiving nut  54  up to the retaining groove  53 . Once the annular projection  49  is inserted into the retaining groove  53  in this way ( FIG. 11 ), the cannula  13  can be rotated relative to the receiving nut  54  about the longitudinal axis of the cannula  13 , whereby the projections  57  and  58  are positioned in a region in the retaining groove  53  in which no recesses  61  and  62  are formed, with the result that the cannula  13  sits in the retaining groove  53  ( FIG. 12 ). 
     The maximum extension D 1  of the annular projection, which is determined by the two projections  57  and  58 , is preferably chosen such that it is slightly larger than the maximum inner width D 2  of the through hole  59  available by means of the recesses  61 ,  62 . In this case, for insertion in the receiving nut  54 , the cannula  13  must be slightly tilted (vis-à-vis the plane of drawing of  FIG. 7 ). It is thus possible, despite the larger extension D 1  of the projections  57  and  58 , to insert the annular projection  49  of the cannula  13  into the receiving nut  54  through the recesses  61 ,  62  up to the retaining groove  53 . The thickness of the retaining groove  53  (extension from left to right in  FIG. 8 ) is chosen such that the base  52  and thus also the annular projection  49  of the cannula  13  can be tilted back in the retaining groove  53  again (there is thus sufficient play between the annular projection  49  and the retaining groove  53 ), with the result that, even without rotating the cannula  13  relative to the receiving nut  54 , a certain retaining function is already provided by the retaining groove  53 . 
     When the receiving nut  54  is screwed on with cannula  13  inserted, the projections  57  and  58  rest on the front side  66  of the retaining groove  53 , with the result that by this means the inner tapered section  51  (or inner cone section  51 ) of the cannula  13  is pressed onto the outer tapered section  50  (or outer cone section) of the adapter  12 . By means of the flat contact of the two tapered sections  50 ,  51  a seal effect is achieved. The desired fluid seal between the channel  11  and the cannula  13  is thus realised and a use of the syringe  1  as intended is possible. 
     When the cannula  13  is to be exchanged, only the receiving nut  54  needs to be unscrewed. During this unscrewing, the rear side  67  of the retaining groove  53  then presses against the projections  57 ,  58  of the base or foot  52  of the cannula  13  and thus pulls the cannula  13  off the inner tapered section  50  of the adapter  12  automatically. It is thus possible to safely detach the cannula  13  since the cannula  13  itself does not need to be handled. Solely by unscrewing of the receiving nut  54 , the cannula  13  is detached from the adapter  12 . 
     The connecting module (cannula  13 , adapter  12  and receiving nut  54 ) was described here in conjunction with the syringe  1  only by way of example. In the connecting module according to the invention, instead of a cannula  13 , another element with a fluid channel, which has a base  52  in the manner described, can also be used. For example, a tube can be connected in this way. Also, the adapter  12  does not have to be a separate element but can be part of the base body  2  or can also be replaced by another element with a fluid channel  11 . The essential factor here is that there is a detachable connection between the two connecting components  13 ,  12  to be connected, in the case of which the connection is detached simply by unscrewing the receiving nut  54 . 
     The above disclosure is related to the detailed technical contents and inventive features thereof. People skilled in this field may proceed with a variety of modifications and replacements based on the disclosures and suggestions of the invention as described without departing from the characteristics thereof. Nevertheless, although such modifications and replacements are not fully disclosed in the above descriptions, they have substantially been covered in the following claims as appended.