WO2008087018A2

WO2008087018A2 - Injection pen comprising a lever

Info

Publication number: WO2008087018A2
Application number: PCT/EP2008/000289
Authority: WO
Inventors: Heinz Fahrni; Jürg HIRSCHEL; Ulrich Moser
Original assignee: Tecpharma Licensing Ag
Priority date: 2007-01-17
Filing date: 2008-01-16
Publication date: 2008-07-24
Also published as: DE102007002548A1; WO2008087018A3

Abstract

The invention relates to an injection device comprising an energy accumulator that can be compressed or tensioned and a tensioning device for tensioning said energy accumulator. The tensioning device has a first compression element and a second compression element. The first compression element can be actuated by a user and is coupled to a multiplication or reduction element. The second compression element is coupled to the energy accumulator for tensioning and the multiplication or reduction element is coupled to the second compression element.

Description

Injection pen with lever

The present invention relates to an injection device for the preferably metered delivery of a substance, such as insulin or hormones, wherein the substance to be dispensed is present for example in an inserted into the injection device ampoule or in the injection device itself.

Ijection devices for delivering a substance are known in the prior art, for example, from WO 2005/097233 A2 and WO 2005/097240 A1.

It is an object of the present invention to propose an injection device for dispensing a preferably smaller dose, which can be operated and drawn up in a simple and effortless manner.

This object is achieved by the injection device according to claim 1. Advantageous embodiments emerge from the dependent claims.

An injection device according to the invention has an energy storage and in particular a tensioned or windable energy storage, which can relax automatically again, such as a spring element or a coil spring, which for clamping and storing energy by a mounting element of a winding or tensioning device, for example compressed or pulled apart. The tensionable energy store is preferably fixedly connected to the injection device on one side or abuts a contact surface of the injection device, whereas on the opposite side of the energy store or spring there is a connection between the energy store and the mounting element, which can be mounted on or in the injection device , is present or the energy storage is applied to the mounting element. According to the invention, a transmission element or reduction element is provided, with which a tightening or pulling-up movement can be over- or reduced. The tensioning or mounting device has a first Aufziehelement which a user directly or indirectly, for example, via a connected to the first Aufziehelement control knob, press. For example, the first Aufziehelement be connected to a retracting button, that a user by pressing or pulling the Aufziehknopfes a winding or tensioning movement of the energy storage and thus the injection device can perform. The first Aufziehelement is coupled to the transfer or reduction element so that the transferred from the Aufziehelement on the transfer or reduction element Aufziehbewegung can be transferred to a second Aufziehelement which is also coupled or connected to the transfer or reduction element and the clamping or Pulling the energy storage, for example, by compressing a spring causes.

Preferably, the transmission or reduction element is a lever or lever element, which is rotatably mounted on or in the injection device. The bearing or pivot point of the lever may either be at an edge region of the lever or may also be in the region between the edge regions, such as in the middle of the lever or a predetermined fraction of the lever length from the edge, such as one third or one quarter of the lever edge removed. The connection of the first and second Aufziehelementes acting as a transmission or reduction element lever may be on the same side of the pivot point, or on opposite sides of the pivot point, wherein according to lever law, for example, a reduction can be realized by the lever arm, Thus, the distance between the connection of the second Aufziehelements with the lever and the pivot point of the lever is smaller than the lever arm defined as the distance between the pivot point of the lever and the connection of the lever with the first Aufziehelement over which a user indirectly or directly the lever can move.

The lever is preferably provided so that the lever axis is perpendicular or approximately perpendicular to the longitudinal axis or axial axis of the injection device, but also other lever arrangements are possible and the lever axis, for example, radially away from the central axis of the injection device, for example, on or in the housing can be.

Thus, the use of a lever preferably used as a reduction element in an injection device, which is preferably designed as autopen with spring, the advantage can be realized that a relatively large force over a relatively small Distance for mounting or tensioning, for example, a spring having a high spring constant spring by a user by pulling out of the lever over- or under-set button can be applied relatively easily and with relatively less force. Furthermore, the display of the set or drawn dose can also be displayed more easily by means of the relatively larger pull-out movement of the button on a larger scale, for example, whereas only a small distance traveled during spring tensioning leads to possible problems with the mechanical display of the set dose can lead.

Preferably, the injection device according to the invention is used in conjunction with a known rack as a piston element, wherein advantageously the spring is stretched so far or limited, for example by a stop can be stretched so far that a corresponding tooth length or a predefined number of tooth lengths dose are distributed can. A dose setting may for example be realized by different Verrastungsmöglichkeiten for different pulled-out distances of the button.

At the proximal end of the piston or rack may preferably be provided an end stop for a last dose, so that after fully retracted piston or rack no further mounting of the injection device is possible.

***

According to a further aspect, the invention relates to a triggering unit for a Iηjektionsvorrichtung with an example biased in the radial direction elastic element or spring arm which is biased, for example, radially inwardly or radially outwardly and which in a non-wound up initial position of the injection device for injection Example over an edge or a latching element of the injection device projects away, so that the spring arm can be moved in the injection device. If the elastic or resilient element is moved in the injection device, for example when applying or setting a dose, the prestressed spring arm according to the invention is coupled to a setting or Aufziehelement that by the example extending in the axial direction adjusting or Aufziehbewegung the prestressed spring arm is moved over the edge or the locking element, for example in the axial direction and through the to Example radially directed bias snaps behind the edge or engages in the locking element. An independent return movement of the spring arm in the axial direction is no longer possible due to the snap caused by the radial bias and the contact of the spring arm on the edge or the locking or locking element, so that when the spring arm is coupled to a dispensing or trip unit , this is not released. Likewise, it is possible that a spring, for example already tensioned, of the injection device can not relax in order to initiate the triggering or dispensing process, since the spring is blocked, for example, by a coupling with the radially prestressed spring arm.

The radially biased spring arm is coupled to a release element, such as a release button, with which the Verrasrung or blocking of the radially biased spring arm can be solved again. For example, by means of a release button of the spring arm can be moved in the radial direction so that it can move past the edge or the locking element, whereby the blockade or blocking is canceled by the radially biased spring arm and, for example, a cocked spring on a piston or a rack Injection device can act to push them, for example, in the distal direction forward. This movement can be limited, for example, by providing a stop element in the direction of movement of the spring arm entrained by the spring tension on which the front or an engagement element of the radially prestressed spring element abuts, for example to interrupt the advancing movement of the piston or toothed rack ,

Preferably, the radially biased spring arm is provided so as to extend along the axial or longitudinal direction of the injection device, wherein the radially biased spring arm, for example, a third, may have half or more of the length of the injection device. This makes it possible for a trigger element or trigger button to be arranged closer to the point of the actual injection, whereas known injection devices usually only have a control element at the proximal end, such as a trigger button.

The invention will be described below with reference to exemplary embodiments. Show it:

Figure IA is an injection device in plan view; Figure IB is a cross-sectional view of the injection device shown in Figure IA;

FIG. 1C shows the injection device rotated by 90 ° in FIG. 1A;

Figure ID is a cross-sectional view of the injection device shown in Figure IC along the line B-B; Figure 2A is an injection device in basic position in plan view;

Figure 2B is a cross-sectional view of the proximal portion of the injection device shown in Figure 2A taken along line A-A;

Figure 2C, the injection device shown in Figure 2 A in the wound state;

FIG. 2D shows a cross-sectional view of the proximal part of the injection device shown in FIG. 2C along the line C-C;

Figure 3A shows an injection device with a spring arm in plan view;

FIG. 3B shows the injection device shown in FIG. 3A in a cross-sectional view along the line A-A;

FIG. 3C is a sectional view of the injection device shown in FIG. 3B taken along the line B-B.

FIG. 1B shows a cross-sectional view of the injection device 1 shown in FIG. 1A, which is shown in a position rotated by 90 ° in FIG. An inserted into the injection device 1 two-chamber ampule 2 has two plugs 2a and 2b, wherein a front or distal end of a rack 3 abuts the proximal plug 2b. The rack 3 is mounted in a known manner by means of two opposite elastic radially inwardly biased latching arms Ia relative to Iηjektionsvorrichtung 1 so that the rack 3 relative to the injection device 3 only in the distal (in Figure 1 to the left) and not in the proximal direction can be moved , For mounting the injection device 1, a button 4 is provided, which can be pulled out of the injection device 1. In the injection device 1, a lever 5 is pivotally mounted on its axis of rotation 5 a perpendicular to the longitudinal axis of the injection device 1, wherein the bearing Ib of the axis of rotation 5 a of the lever 5 is not displaceable relative to the injection device 1.

The lever 5 is coupled via a, for example as rod or rod member of the lever 5 projecting coupling element 5b with a winding and advancing element 6, which radially inwardly biased engagement elements or spring arms 6a, which engage in the toothing of the rack 3, that the Feed element 6 relative to the rack. 3 can only be moved in the proximal direction, ie to the right in FIG. 1D, whereas a relative movement in the opposite direction is not possible.

The lever 5 is connected via a lever engagement or a coupling 5c to the elevator element 6, so that the lever 5 after an elevator movement by pulling the knob 4 from a distal tilt position not shown in Figure 1 in the proximal shown in Figure ID tilted to the right position is pulled. The pull-out movement of the knob 4 thus leads to a tilting or rotation of the lever 5 about the pivot point 5a, whereby the feed element 6 connected to the lever 5 on the coupling 5b is moved in the proximal direction and relative to the held by the holding elements Ia rack 3 shifts. The spring arms 6a are displaced by one or more teeth of the rack 3. The winding and advancing element 6 has a contact surface 6b which is in abutment on one side with a spring 7 or in which a spring end is integrated. The spring 7 is supported on the opposite side on a contact surface Ic of the injection device 1 from.

Since the lever arm, which is formed by the distance D between the pivot point 5a of the lever 5 and the coupling 5c of the lever 5 with the knob 4, is longer than the lever arm, which by the distance d of the fulcrum 5a with the coupling 5b of the Vorschubele - Mentes 6 is formed, the Aufziehbewegung of the knob 4 in the ratio d / D are reduced and thus reduced in a relative to Aufziehbewegung of the button 4 smaller Aufziehbewegung the feed element 6, which due to the law of leverage to D / d greater force for clamping the spring 7 provides.

The Aufziehbewegung for transferring the injection device 1 from the basic position in the wound or loaded position is also visible on the basis of the comparison of the cross-sectional views shown in Figures 2B and 2D. As can be seen from the figures, a reduction of the winding movement can be realized approximately in the ratio 5: 1.

At the proximal end of the rack 3, an end stop 3 a is provided, which is moved with continued payout and thus insertion movement of the rack 3 in the direction of a stop 6d of the winding and advancing element 6 and thus has the consequence that when fully inserted rack 3, at which the end stop 3a of the rack 3 comes into abutment with the stop 6d of the advancing element 6, the Push element 6 can not be raised in the proximal direction. In this way it can be ensured that, for example, in the event of a complete or almost completely discharged ampoule 2, for example, no further pulling-up movement can take place.

The advancing element 6 of the mounted injection device 1 shown in Figure 3B is held in the retracted position against the force of the tensioned spring by the radially outwardly biased spring arm 6c, which is part of the advancing element 6. This was pulled and latched over the edge Id of the injection device 1 by the movement of the advancing element 6 in the proximal direction from the dashed position shown in FIG. 3C, in which the front end of the spring arm 6c is in contact with a contact edge Id of the injection device 1 at the edge Id due to the radially outward bias. In the drawn-up position of the injection device 1 shown in FIG. 3C, therefore, no relaxation of the spring 7 is possible.

To trigger the Inj ektions device 1 acting on the radially outwardly pressing spring arm 6c trigger button 8 is pressed, which again pushes away the front end of the spring arm 6c over the edge Id of the injection device 1 and thus releases the blocking or locking. As a result, the spring 7 pushing on the advancing element 6 is no longer counteracted by a holding force, so that the advancing element 6 can be pressed in the distal direction by the spring 7 and, due to the engagement of the elements 6a, displaces the toothed rack 3 in the distal direction, which presses on the stopper 2b pushes and thus causes a discharge from the ampoule 2.

In this case, the spring arm 6c is moved back into the dashed position drawn in FIG. 3C.

The injection device is again in the starting position and, if the end stop 3a of the rack 3 has not yet been fully inserted into the advancing element 6 until it abuts the surface 6d, it can be re-wound up in preparation for a further dose delivery.

Claims

claims

1. Inj ektions device with an expandable or tensionable energy storage (7) and a tensioning device (4,5,6) for tensioning the energy storage device (7), wherein the tensioning device comprises a first Aufziehelement (4) and a second Aufziehelement (6), wherein the first pull-up element (4) can be actuated by a user and is coupled to a transmission or reduction element (5), the second one

Winding element (6) for clamping with the energy store (7) is coupled and the over- or reduction element (5) with the second Aufziehelement (6) is coupled.

2. Inj ektions device according to claim 1, wherein the tensionable energy storage a

Spring (7), in particular a tension or compression spring, is.

3. Inj ektions device according to any one of the preceding claims, wherein the over or reduction element is a lever (5).

4. Injection device according to the preceding claim, wherein the lever (5) is rotatably mounted on or in the injection device.

5. Inj ektions device according to one of the two preceding claims, wherein a by the distance D between the pivot point (5 a) of the lever (5) and the coupling (5 c) of the lever (5) with the first Aufziehelement (4) formed first lever arm is longer than the second lever arm formed by the distance d of the fulcrum (5a) from the coupling (5b) of the lever (5) with second Aufziehelement (6).

6. Injection device according to one of the three preceding claims, wherein the coupling (5c) of the first Aufziehelementes (4) with the lever (5) and the coupling (5b) of the second Aufziehelements (6) relative to the fulcrum (5a) on the same or lie on the opposite side.

7. Injection device according to one of the four preceding claims, wherein the lever rotation axis is perpendicular to the axial or longitudinal direction of the injection device.

8. Iηjektionsvorrichtung according to any one of the preceding claims with a Aufziehelement (6) with stop surface (6d) and an end stop (3a) of the piston or rack (3).

9. tripping unit for an injection device with a spring arm (6c), which for blocking the injection device to a contact surface of the injection device

(1) can come into abutment and with a release element (8), which can be so coupled to the spring arm (6c) that the spring arm (6c) can be deformed or displaced against its direction of tension to the plant of the spring dam (6c) to solve on the contact surface and the injection device (1) or a feed element (6) of Inj ektionsvorrichtung (1) release.

10. Tripping unit according to the preceding claim, wherein the spring arm (6c) is radially biased with respect to the Iηjektionsvorrichtung.

1 1. trip unit according to one of the two preceding claims, wherein the spring arm

(6c) in the axial direction of the injection device (1).

12. Inj ektionsvorrichtung with a trip unit (6 c, 8) according to one of the three preceding claims.