DETACHABLE NEEDLE PROTECTION CAP FOR INJECTION DEVICES

Abstract

The invention relates to a detachable needle protection cap for injection devices and to a method for producing same. The detachable needle protection cap comprises a housing and at least two shell parts which can be attached to an outer surface of the housing, the shell parts being fastened to an outer surface of the housing. The shell parts can mutually prevent removal of the shell parts.

Claims

1. A detachable needle protection cap for an injection device comprising: a housing, which can be detachably connected to a distal end of an injection device, and together with the injection device, defines a longitudinal axis and radial directions; and at least two shell parts configured to be attached to an external surface of the housing, wherein the external surface of the housing comprises a plurality of holding points and a plurality of guide elements, wherein each of the at least two shell parts comprises at least one fixing element, a blocking element and at least one guide counter-element arranged on an interior of a respective shell part, wherein the at least two shell parts are attachable to the housing by engaging the at least one fixing element of the respective shell part in a respective holding point of the housing, wherein the at least one fixing element of one of the at least two shell parts can be prevented from being released from an engagement with a holding point by a blocking element of another of the at least two shell parts, and wherein for fitting the at least two shell parts to the housing, the guide counter-elements are pushed into the guide elements, wherein the plurality of guide elements of the housing are each configured as one of a groove or a rib arranged perpendicular to the longitudinal axis, and wherein the at least one guide counter-element of each of the at least two shell parts is configured as an other of a groove or a rib, and wherein the grooves comprise undercuts and the ribs engage with the undercuts when the guide counter-elements are pushed into the guide elements, such that when the at least two shell parts are fitted to the housing, the at least two shell parts are held in a radial direction relative to the housing.

2. The detachable needle protection cap according to claim 1, wherein the detachable needle protection cap comprises exactly two shell parts.

3. The detachable needle protection cap according to claim 1, wherein a dovetail is formed between the grooves and ribs when the at least two shell parts are fitted to the housing.

4. The detachable needle protection cap according claim 1, wherein the at least two shell parts are configured identically.

5. The detachable needle protection cap according claim 1, wherein the plurality of holding points comprises a plurality of recesses on the external surface of the housing.

6. An injection device comprising a detachable needle protection cap according to claim 1, wherein the injection device comprises a prefilled syringe and the injection device is an injection pen, an autopen, an autoinjector or a safety syringe.

7. A process for producing a detachable needle protection cap for an injection device, comprising the following steps: providing a housing, sliding and fastening an initial shell part to an external surface of the housing, optionally sliding and fastening a further shell part to the external surface of the housing, permanently securing all slidably fastened shell parts by sliding and fastening a final shell part to the housing.

8. The process according to claim 7, wherein the housing can be detachably connected to a distal end of an injection device, and together with the injection device, defines a longitudinal axis and radial directions.

9. The process according to claim 7, wherein the initial shell part and the further shell part are configured to be attached to the external surface of the housing.

10. The process according to claim 7, wherein the external surface of the housing comprises a plurality of holding points and a plurality of guide elements.

11. The process according to claim 10, wherein each of the initial shell part and the further shell part comprises at least one fixing element, a blocking element and at least one guide counter-element arranged on an interior of a respective shell part.

12. The process according to claim 11, wherein the initial shell part and the further shell part are attachable to the housing by engaging the at least one fixing element of the respective shell part in a respective holding point of the housing, and wherein the at least one fixing element of one of the initial shell part and the further shell part can be prevented from being released from an engagement with a holding point by a blocking element of another of the initial shell part and the further shell part.

13. The process according to claim 11, wherein for fitting the initial shell part and the further shell part to the housing, the guide counter-elements are pushed into the guide elements.

14. The process according to claim 13: wherein the plurality of guide elements of the housing are each configured as one of a groove or a rib arranged perpendicular to the longitudinal axis, and wherein the at least one guide counter-element of each of the initial shell part and the further shell part is configured as an other of a groove or a rib, and wherein the grooves comprise undercuts and the ribs engage with the undercuts when the guide counter-elements are pushed into the guide elements, such that when the initial shell part and the further shell part are fitted to the housing, the initial shell part and the further shell part are held in a radial direction relative to the housing.

15. The process according to claim 7 wherein the plurality of holding points comprises a plurality of recesses on the external surface of the housing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG. 1: three-dimensional or perspective view of the autoinjector 1 with the detachable needle protection cap 100.

[0024] FIG. 2: simplified exploded view of autoinjector 1 with detachable needle protection cap 100, where only the housing 2 of the autoinjector and the needle protection sleeve 6 of the autoinjector are shown (for reasons of clarity, the other parts of the autoinjector are not shown).

[0025] FIG. 3: longitudinal section through the autoinjector 1 and the detachable needle protection cap 100, where in this figure the syringe 3 with needle guard 4 and the syringe holder 5 are also shown.

[0026] FIG. 4a: three-dimensional or perspective view of an alternative embodiment of a shell part 120.

[0027] FIG. 4b: three-dimensional or perspective view of the alternative shell part 120, placed on the housing 110.

[0028] FIG. 5a: three-dimensional or perspective view of a further alternative embodiment of a shell part 120, where the shell part in this case is cut.

[0029] FIG. 5b: three-dimensional or perspective view with partial section of the further alternative shell part 120, placed on the housing 110. The shell part is shown cut.

DETAILED DESCRIPTION

[0030] The following describes preferred embodiments of the detachable needle protection cap for injection devices, to which the invention could be applied, particularly to autoinjectors. In no way should this description be interpreted in a restrictive way, but should simply highlight possible embodiments. For example, the invention could also be used in other injection devices, such as the Ypsomed ServoPen or the Novo Nordisk FlexPen.

[0031] The mechanical part of the autoinjector 1 was omitted from the figures for reasons of clarity. The person skilled in the art is aware of well-known mechanisms, for example, from the applications WO2014/146209A1 or PCT/CH2016/000084, which are herein incorporated by reference in their entireties for any useful purpose.

[0032] FIGS. 1 to 3 show a first embodiment of the invention. FIGS. 4a and 4b show an alternative embodiment of the shell parts; and FIGS. 5a and 5b show a simplified form of the shell with only one shell part.

[0033] FIG. 1 shows the autoinjector 1 together with the fitted detachable needle protection cap 100 in a three-dimensional view. Two shell parts 120 can be seen, which surround the housing 110 (not visible in FIG. 1) of the detachable needle protection cap 100. The housing 110 cannot be seen in this state by the user. The external shape of the shells may vary as already mentioned, and in fact, it is the purpose of the invention to enable a variation of the external shape (i.e. of the geometric external design of the detachable needle protection cap, specifically of the shell parts). The shell parts 120 depicted here serve purely as an example.

[0034] FIG. 2 shows an exploded view of the detachable needle protection cap together with the housing 2 and the needle protection sleeve 6 of the autoinjector 1. The other parts of the autoinjector 1 were left out, as indicated above. The housing 110 of the needle protection cap 100 comprises the recesses 110a into which the teeth 120b of the snap arms 120a can be engaged. The housing 110 also comprises the guide grooves 110b, into which the guide ribs 120c can be pushed when the shell part 120 is pushed on. One shell part 120 also comprises the blocking elements 120e. As mentioned, the shell parts 120 are individually fitted to the housing 110 when the detachable needle protection cap 100 is installed, by sliding the shell parts 120, 120 radially onto the housing 110, where the guide ribs 120c are pushed into the guide grooves 110b. Sliding-on of the shell parts 120, 120 is then complete when the teeth 120b engage in the recesses 110a of the housing 110 provided. Once an initial shell part 120 is installed, a second shell part 120 is pushed onto the opposite side of the housing 110, in a similar way to the first shell part 120. When the second shell part 120 snaps on to the housing 110, the blocking elements 120e of the one shell part 120 also engage with the rear side of the free end of the snap arm 120a in the area of the tooth 120b of the other shell part 120 and vice-versa. The blocking elements 120e prevent the snap arms 120a from being deflected radially outwards (not shown in the figures), thus preventing the snap joint from becoming detached.

[0035] FIG. 3 shows a longitudinal section through the autoinjector 1 and the detachable needle protection cap 100. This figure also shows the syringe 3 with glass body 3a, the movable plug 3b and the injection needle 3c, the needle guard 4 and the syringe holder 5 of the autoinjector 1. What can also be seen is the front part of the needle protection sleeve 6 of the autoinjector 1 with the snap arm 6a. Both shell parts 120 are installed onto the detachable needle protection cap 100. It can be seen in this figure that the guide grooves 110b have undercuts 110c. The guide ribs 120c also have a dovetail 120d, which engages with the undercuts. The function of this embodiment is to minimize the radial mobility of the shell parts 120 in the assembled state and thus to give the combination of housing 110 and shell parts 120 maximum stability. In principle, the user should not notice that the detachable needle protection cap 100 is made up of several parts. The detachable needle protection cap 100 is inserted axially into the autoinjector 1. In this case, the connection between the snap arm 6a of the needle protection sleeve 6 of the autoinjector 1 and the opening 110h of the housing 110 ensures that the detachable needle protection cap 100 remains on the autoinjector 1, where this connection is detachable. On the housing 110, two arms 110f protrude axially in the proximal direction. At their free end of the arms 110f, teeth 110g are arranged, which face radially inward. As can be seen in FIG. 3, the teeth 110g are located behind the proximal end of the needle guard 4. If the detachable needle protection cap 100 is now withdrawn distally from the autoinjector 1, then the proximal end of the needle guard 4 and the teeth 110g engage. If the detachable needle protection cap 100 is further moved distally, the teeth 110g carry the needle guard 4 with them and detach it from the syringe 3, thereby exposing the injection needle.

[0036] FIGS. 4a and 4b show the alternatively developed shell parts 120. The design of the shell parts has been simplified. As with the shell parts of FIGS. 1 to 3, two shell parts are fitted to the housing 110 of the needle protection cap 100 (which is identical to that of FIGS. 1 to 3). Before pushing on the shell parts, two shell parts 120 are welded together along the weld seam which has been prepared with rib shapes and then pushed axially onto the housing 110 until the snap arms 110i are snap-fitted to the snap edge 120a. In this case, when sliding the welded shell parts 120, the guide ribs 120c are inserted into the guide grooves 110k provided. As in the examples of FIGS. 1 to 3, the guide grooves 110k also have undercuts (not shown) and the guide ribs 120c are dovetailed (not shown) so that after the shell parts 120 are installed on the housing 110, any movement of the shell parts 120 in the radial direction relative to the housing 110 can be minimized. In the case of this embodiment too, the external geometry of the shells is merely an example because one aim of the invention is to allow different external shapes.

[0037] FIGS. 5a and 5b show a further simplification of the shell design by making two shell parts into one. Shell part 120 is pot shaped. Instead of two shell parts, only one shell is used in this embodiment, which is pushed onto the housing 110 in an axial direction, where the housing 110 is identical to the previous embodiments. The function of guide ribs 120c and the guide grooves 100k is the same as in the example of FIGS. 4a and 4b. The shell part 120 is snapped over the snap edge 120a of the shell part 120 and the snap teeth 110j of the housing 110.

[0038] Another benefit of the invention described is the design of the housing 110. As will be apparent to the person skilled in the art from the above description, the design of housing 110 described allows many different types of shell to be applied, without this entailing any change to the housing 110 design.

LIST OF REFERENCE NUMBERS

[0039] 1 autoinjector

[0040] 2 autoinjector housing

[0041] 3 syringe

[0042] 3a glass body

[0043] 3b plug

[0044] 3c injection needle or cannula

[0045] 4 needle guard

[0046] 5 syringe holder

[0047] 6 needle protection sleeve of autoinjector

[0048] 6a snap arm

[0049] 100 detachable needle protection cap

[0050] 110 housing

[0051] 110a recess

[0052] 110b guide groove

[0053] 110c undercut

[0054] 110d tooth

[0055] 110f arm of detachable needle guard

[0056] 110g tooth

[0057] 110h opening

[0058] 110i snap arm with tooth

[0059] 110j axially directed snap tooth

[0060] 110k guide groove with undercut

[0061] 120 shell part

[0062] 120a snap arm

[0063] 120b tooth

[0064] 120c guide rib

[0065] 120d dovetail

[0066] 120e blocking element

[0067] 120 alternative embodiment of the shell part

[0068] 120a snap edge

[0069] 120e ribbed preparation for weld

[0070] 120c guide rib with dovetail

[0071] 120 further alternative embodiment of the shell part

[0072] 120a snap edge

[0073] 120c guide rib with dovetail.