Caps for injection devices

Abstract

The present invention discloses a cap for an injection device, the cap comprising a removable needle shield for covering the needle of a syringe in the injection device. The cap comprises a cap body and a first shield engagement portion. The first shield engagement portion is movable relative to the cap body and comprises a first constriction portion. The first constriction portion is configured such that applying a compressive force to the first constriction portion causes the first shield engagement portion to engage with the needle shield so that the needle shield is removed with the cap when the cap is removed from the injection device.

Description

Technical Field

[0001] The present invention relates to the field of injection devices, and in particular to a cap for use with an injection device and a combined cap and injection device. Background Art

[0002] Safety devices are often used with syringes when performing injections in order to reduce the risk of accidental needle sticks, which may lead to the spread of blood-borne pathogens. Such safety devices are often needed to protect healthcare providers, such as doctors and nurses who frequently use syringes to administer injections to patients. These needle safety devices can generally be classified into one of the following two types: (1) passive devices that automatically cover the needle after injection without the user taking additional steps to enable the device; and (2) devices that require the user to perform additional steps to enable the needle safety feature. Passive needle safety devices are generally considered to be superior in their ability to protect users from accidental needle sticks because, for various reasons, the user may not be able to take the additional actions required to enable non-passive devices. Health authorities and healthcare systems often require the use of needle safety devices in environments where healthcare providers (HCPs) perform injections. In addition, needle safety devices are ideal for self-administered and caregiver-administered injections to reduce the risk of injury, infection, and transmission of blood-borne pathogens to patients, family members, caregivers, and anyone who may come into contact with the injection device during the process of performing injections and disposing of used syringes.

[0003] A common example of a manual needle safety device is manufactured by Becton Dickinson The UltraSafe safety device typically consists of two plastic parts that are assembled to the syringe, along with a spring and a custom plunger rod. When the injection is complete, the plunger rod engages a latch on the UltraSafe housing components, which enables the device and causes the spring to extend one of the housing components over the needle and lock it into place. Figure 1A and Figure 1B An example of an UltraSafe device is shown in . Figure 1A The device is shown in a ready state before an injection occurs. Figure 1B The device is shown in a safe-for-use position after an injection has been completed.

[0004] Syringes are particularly difficult for patients and caregivers to use, not only due to the complexity of the steps involved in using the device, but also because syringes with exposed needles often cause anxiety for patients. It would also be desirable to have such a device that could be operated with one hand in a manner that produces consistent needle insertion depth. These and other problems can be overcome through the use of a housing or gripping attachment.

[0005] Prior to use, and to avoid the risk of needle stick injuries, syringes typically include a needle shield. The needle shield is a polymer or rubber-coated sheath that is received over the needle of the syringe. Typically, a plastic needle shield cover is also included over the needle shield to provide rigid support, thereby protecting the needle from bending. The needle shield cover will typically include a friction surface or ribs so that the user can grip the needle shield cover to remove it. The needle shield engages with the needle shield cover so that removal of the cover also causes removal of the needle shield.

[0006] A possible difficulty in using gripping accessories such as those described above is that a portion of the needle shield or needle shield cover may be covered by the gripping accessory. In this case, the difficulty of removing the needle shield may be increased due to the reduced access to the friction surface or ribs of the needle shield or shield cover. Even in the case where the gripping accessory does not bring additional obstacles to the user, the user of such a device may also have difficulties in removing the needle shield and shield cover, because they are unable to grasp and pull the shield and cover with sufficient force to remove. This is usually seen in the elderly population or users with medical conditions that affect dexterity and grip strength. In some cases, the user may not realize that they need to remove the needle shield and shield cover because they are partially obscured by the housing, or they may just forget. For some needle safety devices (such as the UltraSafe series of devices), if the user fails to remove the needle shield and cover before using the device, the syringe will separate from the needle safety device when the needle shield and cover are pressed on the injection site with sufficient force.

[0007] There is a need for a needle safety device that simplifies the process of preparing a syringe for use and reduces the physical burden on the user when preparing the syringe for use, especially when used in conjunction with a manual syringe safety device. There is also a need for a needle safety device that clearly indicates that the needle shield and cap should be removed and prevents the device from being disabled if used improperly. Summary of the invention

[0008] In a first aspect of the invention, a cap for an injection device is disclosed, the cap comprising a removable needle shield for covering a needle of a syringe within the injection device, the cap comprising: a cap body; and a first shield engagement portion, the first shield engagement portion being movable relative to the cap body, the first shield engagement portion comprising: a first constriction portion, the first constriction portion being configured such that application of a compressive force to the first constriction portion causes the first shield engagement portion to engage with the needle shield so that the needle shield is removed with the cap when the cap is removed from the injection device. The cap may provide a clear indication to the user that the needle shield needs to be removed, since the cap is inherently more visible than the needle shield. The cap may also provide a more easily usable hook for the user to remove the shield.

[0009] In one embodiment, the cap further comprises a second shield engaging portion movable relative to the cap body, the second shield engaging portion comprising: a second constricting portion, the second constricting portion being configured such that applying a compressive force to the second constricting portion causes the second shield engaging portion to engage with the needle shield so that the needle shield is removed with the cap when the cap is removed from the injection device. Where the device comprises a second engaging portion, the shield is gripped from two sides, thereby further improving the manageability of shield removal. The user may also grip the second side. In addition, the first shield engaging portion and the second shield engaging portion are diametrically opposed. This configuration allows the shield to be advantageously constricted by the cap for removal. Constriction provides a more efficient removal mechanism. In addition, the first shield engaging portion and the second shield engaging portion are movably coupled by a hinge portion.

[0010] Optionally, the first shield engagement portion and the second shield engagement portion are resiliently deformable such that applying a compressive force to the first constricting portion and the second constricting portion deforms the first shield engagement portion and the second shield engagement portion, thereby causing the first shield engagement portion and the second shield engagement portion to engage the needle shield. This provides a more effective gripping and clamping action on the needle shield to facilitate its removal.

[0011] Optionally, the hinge portion is elastically deformable such that applying a compressive force to the first and second constricting portions deforms the hinge portion, thereby causing the first and second shield engaging portions to engage the needle shield. Such a deformable hinge allows the engaging portion to remain relatively rigid compared to the hinge to improve the grip on the needle shield.

[0012] In addition, the first shield engagement portion may include a friction material configured to grip the needle shield. Such a material improves the grip of the shield without affecting the mechanical and material characteristics of the rest of the cap. The second shield engagement portion may also include a friction material configured to grip the needle shield.

[0013] Optionally, one or both of the first shield engaging portion and the second shield engaging portion comprises an insert of elastically deformable friction material configured to engage the syringe shield. By providing the material in the form of an insert, the remainder of the cap can be formed separately, allowing the selection of a material having properties suitable for the deformation of the cap and the strength required to grasp the needle shield. However, the friction material may also be overmolded onto the cap.

[0014] The friction material may extend through the first constriction and / or the second constriction and form at least one rib for gripping the constriction. This form of arrangement improves the user's grip on the portion of the cap to be engaged, thereby improving the manageability of needle shield removal. These features may also be used to indicate to the user where to place their fingers when gripping the cap and that the cap is a detachable component that should be removed before performing an injection.

[0015] In another embodiment, the first shield engagement portion is configured to contact the syringe shield at a first distance Lc from the hinge portion, and the first constriction portion is configured to be engaged by the user at a second distance Lp from the hinge portion; and wherein the second distance Lp is greater than the first distance Lc. By providing this leverage, the user can apply relatively little force to remove the cap, thereby making the device easier to prepare for injection and requiring less physical effort.

[0016] The cap may also include a housing engagement portion configured to engage with a corresponding cap engagement portion of the housing of the syringe. The housing engagement portion includes a protrusion configured to engage a corresponding notch in the housing of the syringe. Optionally, the housing engagement portion includes a notch configured to engage a corresponding protrusion in the housing of the syringe.

[0017] In addition, the housing engagement portion may be configured to retain or lock the cap within a portion of the syringe housing when the compressive force applied to the first constricting portion is below a threshold unlocking value. Advantageously, the user must squeeze the cap to simultaneously unlock the cap and remove the shield. This ensures that the user knows to squeeze the cap to operate the device, which means that the shield can be removed. Since the cap can be squeezed to engage the shield, the assembly of the device is easier and requires less force. Less force when assembling the device means that the integrity of the injection device is less likely to be affected. In particular, since the cap provides clearance for the needle shield and shield cover when not squeezed, there is little or no interference with the needle shield when the syringe is assembled in the device. This eliminates the risk of affecting the integrity of the container, which would exist for any device where the needle shield or shield cover must be assembled to engage with the cap or removal device. The housing engagement portion may be configured to unlock the cap from a portion of the syringe housing when the compressive force applied to the first constricting portion is above a threshold unlocking value.

[0018] Optionally, the housing engagement portion comprises a cam surface configured to gradually increase compressive force to one or both of the first constricting portion and the second constricting portion when the cap is separated from the housing. Advantageously, the cam may provide assistance to the user when squeezing the cap to remove the protective cover. Alternatively, such a surface may make it easier for the user to pull the cap from the injection device.

[0019] In addition, one or both of the first constriction and the second constriction may include at least one rib, so that the constriction has a tactile feel. One or both of the first constriction and the second constriction may also include a ridge extending outward. Advantageously, the ribs and / or the ridge extending outward may provide the user with more grip in the proximal cap removal direction. This improved grip reduces the amount of squeezing or compression of the wall by the user to an amount suitable for unlocking the cap from the housing. Advantageously, the amount of squeezing required for the user to unlock the cap is similar to or slightly greater than the amount of squeezing required to grip the cap to remove it from the housing.

[0020] Optionally, the cap may also include at least one retaining fixture and at least one corresponding retaining surface, wherein the retaining fixture is configured to engage with the retaining surface so that the first shield engagement portion remains engaged with the needle shield after the compressive force has been removed from the first constriction portion. Advantageously, the shield is then retained within the cap and is less likely to fall out after removal. The user has fewer components to deal with, which improves the manageability of the device in use. The cap may include two retaining fixtures and two corresponding retaining surfaces.

[0021] In addition to the above, two retaining clamps may be disposed on the first side wall and two corresponding retaining surfaces are disposed on the second side wall. Optionally, a first retaining clamp of the retaining clamps is disposed on the first side wall, a first retaining surface of the retaining surfaces is disposed on the second side wall, a second retaining clamp of the retaining clamps is disposed on the second side wall, and a second retaining surface of the retaining surfaces is disposed on the first side wall. Each retaining clamp of at least one retaining clamp may include sharp teeth. Advantageously, the length of the engagement between the cap and the housing stabilizes the cap relative to the housing so that the cap together with the needle shield is easily removed axially and prevents the user from rotating the shield or attempting to remove the shield off-axis. Off-axis removal or rotation of the shield may cause the needle to bend.

[0022] In another embodiment, the cap further comprises at least one tab configured to engage and retain the needle shield within the cap. Advantageously, the shield is then retained within the cap and is less likely to fall out after removal. Thus, the user has fewer components to deal with and handle, which improves the manageability of the device in use. The first shield engagement portion may comprise a first rib configured to abut against the second shield engagement portion such that deflection of the first shield engagement portion is limited. Limiting movement of the shield engagement portion may prevent over-extrusion of the device, which may in fact limit removal of the cap from the device by flexing portions of the cap to contact the housing. Advantageously, the rib also provides visual and tactile feedback that the cap has been squeezed a sufficient amount. Optionally, the second shield engagement portion may further comprise a second rib configured to abut against the first rib such that deflection of the first shield engagement portion and the second shield engagement portion is limited.

[0023] In another embodiment, there is provided a gripping accessory for a syringe, the gripping accessory comprising: a housing configured to hold a syringe; and a cap as described in any of the above aspects. The gripping accessory may also include a syringe.

[0024] In a further embodiment of the present invention, there is provided a manual injection device comprising a grip attachment as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be described with reference to the accompanying drawings, in which:

[0026] Figure 1A to Figure 1B Shown in injection ready state ( Figure 1A ) and safe post-injection status ( Figure 1B ) of a conventional manual injection device;

[0027] Figure 2 Shows the accommodation Figure 1A to Figure 1B A gripping attachment for an injection device;

[0028] FIG. 3A to FIG. 3B According to the present invention, it is suitable for Figure 1A to Figure 1B A perspective view of a cap of a first embodiment for use with an injection device;

[0029] Figure 4 is with Figure 1A to Figure 1B The injection device is combined with FIG. 3A to FIG. 3B An exploded view of the cap;

[0030] FIG. 5A to FIG. 5C According to the present invention, it is suitable for Figure 1A to Figure 1B A side view, a top view and a perspective view of a cap of a second embodiment for use with an injection device;

[0031] FIG. 6A to FIG. 6B is in use FIG. 5A to FIG. 5C a cross-sectional view of the cap; and

[0032] Figure 7 yes FIG. 5A to FIG. 5C A cross-sectional view of a cap;

[0033] Figure 8 According to the present invention, it is suitable for Figure 1A to Figure 1B A top perspective view of a cap of a third embodiment for use with an injection device;

[0034] Fig. 9 yes Figure 8 a side perspective view of the cap; and

[0035] FIG. 10A to FIG. 10C It is a cross section of an alternative tip. Figure 8 A cross-sectional view of a cap. DETAILED DESCRIPTION

[0036] The present invention will be described in illustrative form with reference to the detailed disclosure set forth below with respect to the accompanying drawings.

[0037] Although the exemplary embodiments are depicted with respect to a manual injection device, the skilled person will appreciate that the cap according to the present invention can be used with a variety of injection devices that require removal of the protective cover. Such an injection device may be a manual injection device, a gripping attachment that supports a manual injection device, or an automatic injection device (e.g., an automatic syringe), in which one or more of the needle puncture and plunger actuation may be automatically performed by a drive system. Therefore, the beneficial effects of the cap according to the present invention can be achieved using many types of injection devices that require removal of the protective cover.

[0038] Figure 1A to Figure 1BA manual injection device 100 suitable for use with a gripping attachment and cap according to the present invention is shown. The injection device 100 comprises a syringe 110 extending from a proximal end (including a needle 130) to an open distal end. The open distal end of the syringe is sealed by a stopper. A needle shield 190 is optionally provided to cover the needle 130.

[0039] The syringe 110 is secured within the syringe sheath 120 by a syringe locking element 125. The syringe locking element 125 may include diametrically opposed abutment surfaces between which the flange of a standard syringe is captured. The flange being captured between the abutment surfaces prevents the syringe 110 from moving relative to the syringe sheath 120.

[0040] The syringe shield 120 includes an open distal end into which the syringe 110 can be inserted, and an open proximal end from which the needle 130 extends when the syringe 110 is secured within the shield 120. The safety shield 150 is movably mounted relative to the syringe shield 120. The safety shield 150 can be in a retracted position ( Figure 1A shown) and extended position ( Figure 1B In the retracted position, the needle 130 extends beyond the proximal end of the safety shield, and in the extended position, the safety shield extends beyond the proximal end of the needle. Figure 1B In the second position shown, needle 130 is covered by safety shield 150, thereby shielding the needle from the user and preventing accidental needle stick injuries.

[0041] To allow a user to grasp the injection device 100 using a conventional dart grip, the safety shield 150 includes a flange 155 at or towards its distal end. The flange 155 shown in FIG. 1 extends from the safety shield 150. However, the skilled person will appreciate that the flange 155 may be provided on the syringe sheath 120.

[0042] The safety shield 150 is biased to its extended position ( Figure 1B shown). Figure 1A to Figure 1B The illustrated biasing element 160 takes the form of a coil spring disposed between the syringe sheath 120 and the safety shield 150 such that the safety shield 150 is biased proximally relative to the syringe sheath 120 to its extended position.

[0043] The releasable locking mechanism 180 holds the safety shield 150 in its retracted position relative to the syringe sheath 120. The locking mechanism 180 is movable between a locked position and an unlocked position, in which the locking mechanism 180 prevents the safety shield 150 from moving relative to the syringe sheath 120 ( Figure 1A), in the unlocked position, the locking mechanism 180 no longer prevents movement of the safety shield 150 relative to the syringe sheath 120. Once the locking mechanism moves to its unlocked position, the safety shield 150 moves to its extended position ( Figure 1B ).

[0044] exist Figure 1A to Figure 1B In the illustrated arrangement, the locking mechanism 180 between the safety shield 150 and the syringe guard 120 takes the form of a pair of flexible latch arms 181 disposed on the safety shield 150, which engage opposing latch surfaces 183 on the syringe guard 120. The flexible latch arms 181 are biased to a first position in which they engage their respective latch surfaces 183, thereby preventing proximal movement of the safety shield 150 relative to the syringe guard 120. When the flexible latch arms 181 move against the bias, the latch arms 181 disengage their respective latch surfaces 183, thereby allowing proximal movement of the safety shield 150 relative to the syringe guard 120.

[0045] The latch arm 181 is configured to be moved from the first position to the second position by a custom plunger rod 170. The plunger rod 170 comprises an elongated member configured to engage the stopper 140 at its proximal end and move the stopper proximally along the longitudinal axis of the syringe body to deliver a dose of medicine through the needle 130. At or toward its distal end, the plunger 170 is provided with an actuation surface 175 on which a user can place a thumb or finger to drive the plunger proximally to deliver an injection. When the plunger rod approaches or reaches the end of its travel in the syringe body, the actuation surface 175 of the plunger rod 170 deflects the flexible latch arm 181 outwardly to a position where it no longer engages the latch surface 183 on the syringe sheath 120. The locking mechanism is thus released at the end of the injection, and the safety shield 150 moves to its extended position.

[0046] Although not visible in the attached figure, Figure 1A to Figure 1B The manual injection device may further include a safety lock for locking the safety shield 150 in its extended position after the injection is completed.

[0047] Now refer to Figure 2 Description and Figure 1A and Figure 1B Gripping attachment for use with an injection device.

[0048] like Figure 2As shown, the grip attachment 300 includes a housing 310 having a distal portion 330, a proximal portion 320, and an intermediate portion 340 extending between the proximal portion and the distal portion. The distal portion 310 of the housing 330 includes a distal opening 335 to allow the injection device to be inserted into the generally hollow body. Proximally of the distal opening, the housing 310 includes two recesses 352 that define the flange 155 of the safety shield 150 and secure the injection device 100 within the housing. With the flange 155 defined in the recesses 352, the syringe 110 and the needle 130 are secured relative to the grip attachment 300 until the locking mechanism 180 is released.

[0049] To facilitate insertion of the injection device 100 into the housing 310, an inclined surface (not shown) may be provided on the interior of the housing 310 immediately distal to the recess 352, which guides the flange 155 of the injection device 100 into the recess 352. Once the flange 155 passes over the ramp (not shown) and snaps into the recess 352, the injection device 100 is locked into the grip attachment 300. In some aspects, though not all, the housing further includes ribs on the interior of the housing for preventing lateral and rotational movement of the injection device 100 within the housing 310.

[0050] like Figure 2 As shown, the distal portion 330 of the housing 310 may at least partially surround the locking mechanism 180 of the injection device 100 to provide a shield around the locking mechanism 180 of the injection device 100. The shield prevents the user's hand from directly contacting the locking mechanism 180 and inadvertently moving to release the locking mechanism 180 and activate the needle shield before the injection is completed. In order to allow the user to observe the distal end of the injection device 100, the distal portion 330 may include one or more cutouts 380. If the user pushes the plunger rod substantially sideways when injecting, the cutout 380 also provides space for the plunger rod to clear the housing without preventing the plunger rod from being pressed.

[0051] In various embodiments, the gripping accessory is provided with a housing cap of the present invention. The housing cap may be configured to at least partially close the proximal opening of the gripping accessory. Preferably, the housing cap comprises a sheath for enclosing a needle shield of the injection device. The housing cap may be configured so that the needle shield is removed from the needle simultaneously with the housing cap. This may be achieved by providing an engagement feature on the inner surface of the housing cap that grips the needle shield or needle shield cover during removal.

[0052] In some embodiments, the housing cap may include at least one engagement feature for engaging one or more corresponding engagement features on the housing of the grip attachment. The engagement feature secures the housing cap in place at the proximal end of the grip attachment housing.

[0053] The engagement features on the housing cap may include one or more locking tabs on an outer surface of the housing cap.The engagement features on the grip attachment housing may include a locking groove on an interior of the housing sized to receive the locking tabs.

[0054] In some embodiments, the generally hollow body of the grip accessory housing may include a guide for guiding the locking tab into the corresponding locking groove. For example, the guide includes a channel extending proximally from the locking groove and may be sized to receive the locking tab and guide the tab toward the locking groove. The locking tab may include a distal chamfered edge to guide the locking tab into the locking groove. Alternatively, the locking groove may be provided on the housing cap and the locking tab may be provided on the grip accessory housing.

[0055] See now FIG. 3A to FIG. 3B and Figure 4 According to the first embodiment of the present invention, the gripping attachment may be provided with a housing cap 400. The housing cap 400 is configured to cover the needle 130 and the needle shield 190 of the injection device 110. Figure 4 As shown, the housing cap 400 extends from and closes the proximal opening 360 of the housing 310. Removing the housing cap 400 from the gripping attachment 300 removes the needle shield 190 from the needle, thereby preparing the injection device 110 for injection. Since the housing cap 400 is clearly visible on the proximal portion 320 of the housing 310, the housing cap 400 prevents misuse of the device by failing to remove the needle shield 190, which is typically not always easily visible to the user in the gripping attachment 310. Further improvement in the visibility of the housing cap 400 can be achieved by providing the housing cap 400 in a color that contrasts sharply with the color of the body of the gripping attachment. As a non-limiting example, a blue housing cap provided in combination with a white or off-white gripping attachment provides an improved visual indication that the housing cap 400 should be removed from the device prior to use.

[0056] Now refer to Figure 3A and Figure 3B The housing cap 400 is described in more detail. Figure 3A and Figure 3BAs shown, the outer shell cap 400 includes a sheath 410 that is partially split along its length to form a first side wall 412 and a second side wall 414 separated by a cutout 416. The first side wall 412 and the second side wall 414 generally form a cavity for receiving a needle assembly including a needle 130 and a needle cap 190, and a needle cap engagement device for fixing the needle cap 190 within the outer shell cap 400, such as a plurality of claws or elastically deformable portions (including friction surfaces). However, the skilled person will recognize that the cavity of the outer shell cap 400 may be provided with an integral needle shield for sealing the needle 130 of the injection device. In any case, the removal of the cap 400 is configured to extract the needle to be inserted into the injection site.

[0057] The housing cap 400, and specifically the first side wall 412 and the second side wall 414, are formed of an elastically flexible material such that when a force F is applied to the first side wall and the second side wall, the first side wall 412 and the second side wall 414 can be moved from a first position to a second position, such as Figure 3A As shown. The force P applied by the contraction motion causes the first side wall 412 and the second side wall 414 to move toward each other. Figure 3A and Figure 3B In the embodiment shown, since the cutout 416 separates the first side wall and the second side wall, it is possible for the two side walls to move toward each other. However, it will be appreciated by the skilled person that other arrangements that allow the first side wall and the second side wall to flex inwardly toward each other are possible. For example, in an alternative embodiment, the cap 400 may include a sheath 410 in which the cutouts 412, 414 are replaced with a material having a higher flexibility relative to the first side wall 412 and the second side wall 414. Other ways of providing a squeezable cap will be apparent to those skilled in the art.

[0058] like Figure 3A and Figure 3B As shown, the first sidewall and the second sidewall each include at least one housing engagement feature, such as a locking tab 420 on an outer surface of each of the first sidewall 412 and the second sidewall 414. The locking tab 420 is configured to mate with one or more corresponding cap engagement features 430 on an inner surface of the housing 310. The cap engagement features on the housing 310 may take the form of a locking groove 430 that may be sized to receive the locking tab 420 disposed on the housing cap 400. Of course, the skilled artisan will recognize that the locking tab 420 may alternatively be disposed on the grip accessory housing 310, with the corresponding groove 430 for receiving the locking tab being located on the cap 400.

[0059] like Figure 3BAs shown, in some (but not all) embodiments, the locking tab 420 can include a chamfered distal edge 421 to help guide and deflect the locking tab 420 into a corresponding locking feature on the housing during assembly.

[0060] like Figure 3A and Figure 3B As shown, the cap 400 may also include a gripping surface 440. The gripping surface is coupled to or integrally formed with the first side wall 412 and the second side wall 414 such that pressure applied to the gripping surface 440 deflects the first side wall 412 and the second side wall 414 to their second positions. FIG. 3A to FIG. 3B In the preferred embodiment shown, the gripping surfaces are generally planar, opposing surfaces. This provides a larger surface area for gripping and ensures that the constriction force is correctly applied to deflect the first sidewall and the second sidewall toward each other. In some embodiments, the gripping surface 440 may also include surface features that further assist the gripping of the housing cap 400, such as areas with ridges.

[0061] If desired, the locking tab 420 may include a chamfered edge to facilitate replacement of the cap. The chamfered edge of the locking tab 420 guides the locking tab into position in a corresponding locking groove on the housing.

[0062] like FIG. 3A to FIG. 3B As shown, the cap 400 may also include a flange 450 extending from the first and second gripping surfaces 440 that closes an aperture at the proximal end of the gripping attachment housing.

[0063] like Figure 4 As shown, in an embodiment of a grip attachment provided with a housing cap 400, the grip attachment 300 may further include a guide 810 for guiding the locking tab 420 into a corresponding cap engagement feature on the housing. Figure 4 As shown, the guide means may include a groove extending proximally from the cap engagement feature in the housing along which the locking tab 420 may slide toward the cap engagement feature.

[0064] exist FIG. 5A to FIG. 5C A second embodiment of a housing cap 500 according to the present invention is shown in FIG. FIG. 5A to FIG. 5C In the embodiment of the present invention, the outer shell cap 500 includes a first side wall 512 and a second side wall 514 formed of an elastic flexible material, so that when a compression force P is applied to the first side wall and the second side wall, the first side wall 512 and the second side wall 514 can be moved from a first position to a second position, such as Figure 5B shown.

[0065] The application of force P by the contracting motion causes the first side wall and the second side wall to move toward each other. The movement of the first side wall and the second side wall toward each other is possible because the cutout separates the first side wall 512 and the second side wall 514 and provides space for the first side wall and the second side wall to move. When the first side wall and the second side wall move together, the engagement portion 520 is configured to engage with a needle shield or needle shield cover that is disposed on either side within the central channel defined by the first side wall and the second side wall.

[0066] Now refer to FIG. 6A to FIG. 6B , it can be seen that the housing cap 500 is configured such that the application of the compression force P provides a mechanical advantage over the contact force Cf applied by the engagement portion 520. Figure 7 This mechanical advantage can be more easily understood; the outer shell cap is shown in a cross-sectional view, the section being taken at the symmetry plane of the outer shell cap 500. Figure 7 ), the first side wall and the second side wall converge at the hinge portion 530. The first side wall and the second side wall effectively "pivot" or flex about the hinge portion by the lever action applied to the tightening portion 540. The tightening portion of the housing cap is located at a point on the first side wall and / or the second side wall that is a distance Lp from the hinge portion 530. The engaging portion 520 is configured to engage the syringe shield or syringe shield cover at a distance Le from the hinge portion. Because the engaging portion 520 and the tightening portion 540 move substantially together in a pivoting manner about the hinge portion, the torque applied at the tightening portion 540 is equal to the torque applied by the engaging portion 520 to the needle shield or needle shield cover. The distance Lp of the tightening portion from the hinge portion 520 is greater than the distance Le of the engaging portion from the hinge portion, so the force actually applied by the engaging portion engaging the needle shield or needle shield cover is greater than the force applied by the user to the tightening portion.

[0067] It should be understood that the engagement portion can be formed separately from the outer shell cap, but assembled with the outer shell cap. However, alternatively, the engagement portion can be formed continuously with the outer shell cap or include a part of the outer shell cap. In addition, the engagement portion can be made of the same material as the outer shell cap, or alternatively the engagement portion can be made of a material different from the outer shell cap. In the case where the material of the engagement portion is different from the material of the outer shell cap, it should be understood that an elastic material such as rubber or an elastomer can be selected so that the engagement friction increases. In a preferred embodiment, in the case where the engagement portion is configured to engage a needle shield cover that is usually more rigid than the needle shield, the engagement portion is formed by a softer material such as rubber or an elastomer; in the case where the engagement portion is configured to engage the needle shield itself (which is usually formed by an elastomer), the engagement portion is formed by an elastic polymer. In either case, one of the engagement portion and the needle shield or the needle shield cover is formed by a more rigid material, and the other is formed by a less rigid, elastically deformable material.

[0068] In a second embodiment, if Fig. 6A As shown, one or both of the first sidewall and the second sidewall include a prong 685 on the outer surface of one or both of the first sidewall and the second sidewall. One or more prongs 685 are configured to engage a complementary recess 686 on the interior of the housing of the gripping attachment. When the first sidewall and the second sidewall are resiliently biased to the first position, the prongs 685 engage with the recess 686 so that they hold the housing cap in place and prevent it from being removed from the gripping attachment. The prongs include a locking surface 688 that engages with a complementary recess locking surface 687 to prevent the cap from moving out of the housing proximally. The prongs 685 are configured so that when a constriction force P is applied to the first sidewall and the second sidewall, they do not prevent the housing cap from being removed. The locking surface of the prong and the complementary recess locking surface engage when the first sidewall and the second sidewall are in the first position, and are no longer engageable when the first sidewall and the second sidewall are compressed together. In this way, the prongs 685 serve to hold the housing cap on the device before being removed for the purpose of using the device.

[0069] like Fig. 6A As shown, the prongs are also configured so that they increase the contact force applied to the needle cap. The prongs include a cam surface 689 that is configured to gradually engage the inner surface of the grip attachment when the outer shell cap is removed from the grip attachment. The slope of the cam surface is provided so that the gradual increase in contact force during the removal of the outer shell cap is predetermined. The increase in the angle of the slope provides a greater rate of increase in the contact force applied when the outer shell cap is removed. This cam action for further closing the first side wall and the second side wall together and further increasing the contact force applied to the needle cap reduces the force required by the user to compact the first side wall and the second side wall together.

[0070] Additionally, the camming action of the prongs to increase the contact force provides finer control of the contact force without burdening the user with applying the correct force. Without the prongs it may be difficult for the user to apply a consistent and sufficient compression force to apply the proper contact force, whereas with the prongs the ultimate contact force is partially dependent on the size and configuration of the prongs.

[0071] Now refer to Fig. 6A and Figure 6B , the process of removing the cap of the present invention will be described. In use, when the user applies a tightening force P to the first side wall and the second side wall, the first side wall and the second side wall overcome the elastic bias provided by the hinge portion of the outer shell cap and move inward or flex. The hinge portion of the outer shell cap includes a portion that is specifically intended to deform so that the first side wall and the second side wall can move together. The hinge portion is formed of the same material as the first side wall and the second side wall and is formed continuously with the first side wall and the second side wall. Alternatively, the technician should understand that any other form of hinged connection may be used, for example, the hinge portion may include a mechanical hinge with a bearing surface or a movable hinge that undergoes plastic deformation to provide flexibility.

[0072] exist Fig. 6A , the first side wall and the second side wall have been compressed together, but the cap has not been removed proximally from the housing. Figure 6B , the cap is in the second stage where the user has begun to remove the cap from the housing. The needle shield and the needle shield cover have been partially removed from the needle, but not completely removed from the needle. As the user continues to pull the housing cap proximally, the cam surface of the pointed tip engages the inner surface of the housing, thereby applying further force to the first side wall and the second side wall, which tends to bias the first side wall and the second side wall to grasp the needle shield cover and the needle shield with greater force. At this time, if the user reduces the force applied when tightening the first side wall and the second side wall together, trying to pull the cap proximally with more force, the cap tends to assist in grasping the needle shield and the needle shield cover to compensate for the reduced tightening effect.

[0073] like Figure 5B and Figure 5C As shown, the first side wall includes a clamp 545 having retaining tines 546. The second side wall includes a corresponding retaining surface 547 that can engage with the tines 546 of the clamp to retain the first and second side walls in a second, contracted position once a threshold deflection caused by contraction of the first and second side walls has been reached. Figure 5B and Figure 5CThe embodiment of the embodiment shows two clamps on the first side wall and two retaining surfaces on the second side wall, but it should be understood that any number of clamps and corresponding retaining surfaces can be used to similar effect. Similarly, the outer shell cap may include a clamp on the first side wall and a clamp on the second side wall, each clamp having a corresponding retaining surface on the opposite side wall. In use, once the clamps have been retained by the retaining surfaces, the first side wall and the second side wall of the outer shell cap are retained in engagement with the needle shield cover and the needle shield, so that the user does not need to continue to apply a tightening force to engage the needle shield cover and the needle shield.

[0074] In a third embodiment, if Figure 8 As shown, a housing cap for an injection device is provided. The housing cap of the third embodiment is similar to the housing cap of the second embodiment, but is constructed as described below in addition. Housing cap 800 comprises a sheath 810, which is partially split along its length to form a first side wall 812 and a second side wall 814 separated by an incision 816. Except for the incisions of the separation first side wall 812 and the second side wall 814 provided in the sheath, each side wall is also separated from the main body of the sheath by a pair of longitudinal slots 818. The longitudinal slots allow the cantilever action of the first side wall and the second side wall to extend further along the main body of the sheath.

[0075] In addition, refer to Figure 8 , the first and second side walls include flared portions or laterally extending portions 817 at their proximal ends. The flared portions 817 provide additional reaction surfaces for a user to grasp even after the first and second side walls have deflected together.

[0076] The first sidewall 812 and the second sidewall 814 also include a rubber gripping surface 830 respectively. The rubber gripping surface 830 can be overmolded on the inner surface of each sidewall. Alternatively, the rubber gripping surface can be formed separately with the rest of the shell cap, and then fixed to the shell cap with, for example, adhesive or by press fit. The shell cap can also include one or more sockets 831, which are configured to receive a part of the rubber gripping surface, thereby increasing the adhesion or retention of the rubber gripping surface in the shell cap. In the case of overmolded rubber gripping surfaces, socket 831 can also provide access for the material to be formed of the rubber gripping surface so as to be overmolded after injection. In addition, the socket can provide some rubber gripping surfaces to extend through the sidewall and protrude and provide ribs 832 or protrusions, thereby strengthening gripping so as to pull the shell cap from the shell.

[0077] See now Fig. 9, rib 926 extends from the inner edge or inner surface of at least one of the first sidewall and the second sidewall. Optionally, the second rib 926 also extends from the opposite inner edge or inner surface of the other of the first sidewall and the second sidewall. One or more ribs 926 extend so that when the two sidewalls deflect together, one rib 926 either engages with the opposite sidewall or engages with the opposite rib 926 (if the second rib 926 is present). In this way, the movement of the two sidewalls together is hindered, thereby preventing excessive compression of the sidewalls. If the user grasps the outer shell cap too tightly, excessive compression of the sidewalls may occur. When the outer shell cap is overcompressed once the needle shield has engaged the sidewall, it is not simply flexed inwardly to engage the needle shield, but further compression of the sidewall at the proximal end causes the sidewall to flex or bend around the needle shield. When the sidewall flexes around the needle shield, the distal end of the sidewall protrudes outward away from the central axis of the outer shell cap. This outward protrusion may cause the sidewall to engage with the inner surface of the outer shell and resist or prevent the outer shell cap from being removed from the outer shell. By providing one or more ribs at a location more proximal than the point of engagement with the needle shield, outward protrusion of the side wall is reduced or eliminated, thereby reducing the trapping effect of the housing on the housing cap.

[0078] The one or more ribs also provide enhanced feedback to the user that the sidewall has been sufficiently compressed to facilitate removal of the needle shield. This is achieved through visual feedback: the user is able to see that the ribs have made contact when it is more difficult to see whether the needle shield has been sufficiently engaged. This is also achieved through mechanical feedback: when the ribs are engaged, they provide resistance to compression of the sidewall that is stronger or more rigid than the resistance created by engagement with the needle shield or needle shield cover. The more rigid response to compression can be easily detected by the user and provides an indication that the sidewall has been sufficiently compressed.

[0079] Also refer to Fig. 9 , the cap includes at least one retaining tab 948 extending from the side wall of the outer shell cap. The cap may also include a second retaining tab 948 extending from the same or opposite side wall of the outer shell cap. In either case, the second retaining tab 948 extends from the side wall and is diametrically opposite to the first retaining tab 948 relative to the needle shield and the shield cover, so that the retaining tab 948 engages with the needle shield cover. The one or more retaining tabs 948 are configured so that when the needle shield has been removed and the side wall is no longer compressed, the retaining tab 948 remains engaged with the needle shield cover so that the needle shield remains captured in the outer shell cap.

[0080] Referring now to FIG. 10 , various exemplary embodiments of the tip will be described. Fig. 10A A first embodiment of the tip is shown in FIG. Similar to the tip described above, Fig. 10AThe tip in the housing cap comprises a locking surface 1001 and a cam surface 1002. The locking surface 1001 extends vertically from the outer surface of the side wall and therefore prevents the housing cap from being removed from the housing. Since the locking surface 1001 extends vertically, the force of pulling the housing cap from the housing alone will not unlock the tip from the complementary recessed portion in the housing. Only by compressing the side walls together by a predetermined amount can the housing cap be allowed to move outward from the housing. Once the side walls have been compressed together by a predetermined distance, pulling the housing cap from the housing will cause the cam surface 1002 of the tip to engage with the inner edge of the complementary recessed portion. The slope of the cam surface can cause the compression of the side wall to be slightly greater than the predetermined unlocking compression when the housing cap is taken out from the housing, or the user can continue to compress the side wall manually. When the housing cap is further removed from the housing, the tip can engage with the inner surface of the housing, thereby maintaining the compression level of the side wall until the tip is exposed from the proximal end of the housing. The user's experience during the removal process is that a high level of compression is required to initially remove the needle shield, but once the initial removal phase has been completed, the compression required by the user is released while the needle shield is still removed along with the housing cap. The axial position of the tip on the housing cap and the length between the complementary recessed portion of the inner surface of the housing and the proximal end determine the removal length over which the tip holds the sidewall in compression. The removal length can be determined so that the tip remains compressed until after the needle shield has been sufficiently removed so that there is no or little force holding the needle shield on the syringe.

[0081] exist Fig. 10B A second embodiment of the tip is shown in FIG. Fig. 10B The tip and Fig. 10A The prong of is different in that it does not include a vertical locking surface. Fig. 10B The tip of the tip includes a cam surface 1003 extending from the side wall surface to the tip of the tip. The angle of the cam surface 1003 is selected so that it prevents accidental removal of the housing cap or locks the housing cap in place. In an exemplary embodiment, the angle of the cam surface is 37°. Fig. 10B In the embodiment of the present invention, the cam surface 1003 is continuous, that is, there are no sharp edges or interruptions in the cam surface. The continuous cam surface provides smooth removal of the housing cap from the housing, because interruptions or sharp edges can create additional resistance.

[0082] Now go to Fig. 10CIn an embodiment of the present invention, the cam surface of the tip is divided into two discontinuous sections. The first section encountered by the inner edge of the complementary recess is the first steep locking surface 1004. The first surface is not arranged perpendicular to the side wall, but is steep enough so that the housing cap cannot be accidentally removed. Once the side wall has been manually compressed and the removal of the housing cap has begun, the inner edge of the complementary recess reaches the interrupted portion and the relatively shallow second surface 1005. The angle of the second surface provides less resistance to the removal of the housing cap, and the compression applied to the side wall can be gradually increased when the housing cap is removed. The discontinuous cam surface provides an accurate point at which the housing cap is "unlocked" and can be easily pulled from the housing. Such tactile feedback helps the user of the device understand the process of using the device.

[0083] In all embodiments including one or more prongs, the prongs may or may not promote compression of the sidewall. Specifically, where the prongs do not promote compression of the sidewall, the size and shape of the prongs are configured such that the cap is unlocked for removal from the injection device only after the user has applied sufficient compression to the sidewall to remove the needle shield and shield cover.

[0084] The present invention has been described above by way of example with reference to the accompanying drawings.

Claims

1. A cap for an injection device, the injection device comprising a removable needle shield for covering a needle of a syringe within the injection device, the cap comprising: Cap body; A first shield engaging portion, the first shield engaging portion being movable relative to the cap body, the first shield engaging portion comprising: a first constricting portion configured such that application of a compressive force to the first constricting portion causes the first shield engaging portion to engage the needle shield so that the needle shield is removed with the cap when the cap is removed from the injection device; and a second shield engaging portion movable relative to the cap body, the second shield engaging portion comprising: a second constricting portion configured such that application of a compressive force to the second constricting portion causes the second shield engaging portion to engage the needle shield so that the needle shield is removed with the cap when the cap is removed from the injection device; wherein the first shield engaging portion and the second shield engaging portion are movably coupled by a hinge portion; and The first shield engagement portion and the second shield engagement portion are elastically deformable, so that applying a compressive force to the first constriction portion and the second constriction portion deforms the first shield engagement portion and the second shield engagement portion, thereby causing the first shield engagement portion and the second shield engagement portion to engage with the needle shield.

2. The cap of claim 1, wherein the first shield engaging portion and the second shield engaging portion are diametrically opposed.

3. The cap of claim 1 , wherein the hinge portion is elastically deformable such that applying a compressive force to the first constricting portion and the second constricting portion deforms the hinge portion, thereby causing the first shield engaging portion and the second shield engaging portion to engage the needle shield.

4. The cap of claim 1, wherein the first shield engagement portion comprises a friction material configured to grip the needle shield.

5. The cap of claim 1, wherein the second shield engagement portion comprises a friction material configured to grip the needle shield.

6. The cap of claim 4 or claim 5, wherein one or both of the first shield engaging portion and the second shield engaging portion comprises an insert of a resiliently deformable friction material configured to engage the needle shield.

7. A cap as claimed in claim 4 or claim 5 wherein the friction material is overmoulded onto the cap.

8. The cap of claim 7, wherein the friction material extends through the first constricted portion and / or the second constricted portion and forms at least one rib for gripping the constricted portion.

9. The cap of claim 1 , wherein the first shield engagement portion is configured to contact the syringe shield at a first distance Lc from the hinge portion, wherein the first constricted portion is configured to be engaged by a user at a second distance Lp from the hinge portion; and wherein the second distance Lp is greater than the first distance Lc.

10. The cap of claim 1, further comprising a housing engagement portion configured to engage with a corresponding cap engagement portion of a housing of a syringe.

11. The cap of claim 10, wherein the housing engaging portion comprises a protrusion configured to engage a corresponding cutout in the housing of a syringe.

12. The cap of claim 10, wherein the housing engagement portion comprises a cutout configured to engage a corresponding protrusion in the housing of a syringe.

13. The cap of any one of claims 10 to 12, wherein the housing engagement portion is configured to retain or lock the cap within a portion of the syringe housing when the compressive force applied to the first constricting portion is below a threshold unlocking value.

14. The cap of any one of claims 10 to 12, wherein the housing engagement portion is configured to unlock the cap from within a portion of the syringe housing when the compressive force applied to the first constricting portion is above a threshold unlocking value.

15. The cap of any one of claims 10 to 12, wherein the shell engaging portion includes a cam surface configured to gradually increase the compressive force toward one or both of the first constricting portion and the second constricting portion when the cap is separated from the shell.

16. The cap of claim 1, wherein one or both of the first constricted portion and the second constricted portion include at least one rib such that the constricted portion is tactile.

17. The cap of claim 1, wherein one or both of the first constricted portion and the second constricted portion include an outwardly extending ridge.

18. The cap of claim 1 , further comprising at least one retaining clamp and at least one corresponding retaining surface, wherein the retaining clamp is configured to engage with the retaining surface such that the first shield engagement portion remains engaged with the needle shield after the compressive force has been removed from the first constricting portion.

19. The cap of claim 18, wherein the cap comprises two retaining clamps and two corresponding retaining surfaces.

20. The cap of claim 19, wherein the two retaining clips are provided on a first side wall and the two corresponding retaining surfaces are provided on a second side wall.

21. A cap according to claim 20, wherein a first retaining clamp in the retaining clamps is arranged on the first side wall, a first retaining surface in the retaining surfaces is arranged on the second side wall, a second retaining clamp in the retaining clamps is arranged on the second side wall, and a second retaining surface in the retaining surfaces is arranged on the first side wall.

22. The cap of any one of claims 18 to 21, wherein each of the at least one retaining clamps comprises tines.

23. The cap of claim 1, further comprising at least one tab configured to engage and retain the needle shield within the cap.

24. The cap of claim 1, wherein the first shield engaging portion includes a first rib configured to abut the second shield engaging portion such that deflection of the first shield engaging portion is limited.

25. The cap of claim 24, wherein the second shield engaging portion includes a second rib configured to abut the first rib such that deflection of the first shield engaging portion and the second shield engaging portion is limited.

26. A gripping accessory for a syringe, the gripping accessory comprising: a housing configured to hold a syringe; as well as Cap according to any one of the preceding claims.

27. The gripping attachment of claim 26, further comprising a syringe.

28. A manual injection device comprising a grip attachment according to claim 26 or claim 27.

Images