Case 1:22-cv-00023-JPB Document 2-7 Filed 03/18/22 Page 1 of 9 PageID #: 244
`
`
`
`
`
`Exhibit G
`
`
`
`
`
`

`

`Case 1:22-cv-00023-JPB Document 2-7 Filed 03/18/22 Page 2 of 9 PageID #: 245
`IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII
`US009132239B2
`
`(12) United States Patent
`Moiler et al.
`
`(10) Patent No. :
`(45) Date of Patent:
`
`US 9,132,239 B2
`Sep. 15, 2015
`
`(54) DIAL-DOWN MECHANISM FOR WIND-UP
`PEN
`
`(75)
`
`Inventors: Claus Schmidt Moiler, Fredensborg
`(DK); Tom Hede Markussen, Bagsva:rd
`(DK); Bo Radmer, Hillernd (DK);
`Christian Peter Enggaard, Vejby (DK)
`
`(73) Assignee: Novo Nordisk A/S, Bagsvaerd (DK)
`( * ) Notice:
`
`the term of this
`Subject to any disclaimer,
`is extended or adjusted under 35
`patent
`U.S.C. 154(b) by 833 days.
`
`(21) Appl. No. :
`
`13/124, 995
`
`(22) PCT Filed:
`
`Oct. 21, 2009
`
`(86) PCT No. :
`) 371 (c)(I),
`(2), (4) Date:
`
`PCT/EP2009/063801
`
`Aug. 1, 2011
`
`(87) PCT Pub. No. : WO2010/046394
`PCT Pub. Date: Apr. 29, 2010
`
`(65)
`
`US 2012/0095410 Al
`
`Prior Publication Data
`Apr. 19, 2012
`
`Related U.S.Application Data
`application No. 61/109,242, filed on Oct.
`
`Provisional
`29, 2008.
`
`Foreign Application Priority Data
`
`(60)
`
`(30)
`
`Oct. 24, 2008
`
`(EP) ...
`
`08167547
`
`(51)
`
`Int. Cl.
`A 61/If 5/00
`A 61/If 5/315
`A6/M 5/20
`
`(2006.01)
`(2006.01)
`(2006.01)
`
`(52) U.S. Cl
`CPC ............. A61/If 5/31525 (2013.01);A6/M 5/20
`(2013.01);A6/M 5/3/56 (2013.01);A6/M
`5/31553 (2013.01)
`
`(58) Field of ClassiTication Search
`CPC ....... A61M5/00; A61M 5/3129; A61M 5/24;
`A61M 5/2033; A61M 5/3287; A61M 5/32;
`A61M 5/178; A61M 2005/206
`USPC ............................. 604/187, 136, 272, 164.11
`See application file for complete search history.
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`4,584,439 A
`4,924,737 A
`
`4/1986 Paddock
`5/1990 Gummow
`
`(Continued)
`
`FOREIGN PATENT DOCUMENTS
`
`AU
`CN
`
`595723
`1214292 A
`
`1/198 8
`4/1999
`
`(Continued)
`
`OTHER PUBLICATIONS
`
`U.S. Appl. No. 10/610, 926 which is owned by the same assignee as
`U.S. Appl. No. 11/765, 789, filed Jun. 20, 2007 by Moiler et al.
`
`Scott Medway
`Primary Examiner
`(74) Attorney, Agent, or Firm
`Wesley Nicolas
`
`ABSTRACT
`(57)
`invention relates to a dial-down mechanism for
`The present
`an injection device comprising a torsion spring for assisting
`injection of a dose of medicament
`from the injection device,
`arm (21)
`the dial-down mechanism comprising
`a ratchet
`engaging a ring element (10) and a reset element
`(30) which
`acts on a knob located on the periphery ofthe ratchet arm (21)
`to move the ratchet arm (21) out of engagement with the ring
`(10) in order to allow the set dose to be reduced.
`element
`
`3 Claims, 3 Drawing Sheets
`
`34
`
`20
`
`30
`
`13
`
`24
`
`12
`
`35
`
`14
`
`20
`
`10
`
`26
`
`36
`
`32
`
`21
`
`34
`
`27
`
`32
`
`36
`
`13
`
`26
`
`10
`
`

`

`Case 1:22-cv-00023-JPB Document 2-7 Filed 03/18/22 Page 3 of 9 PageID #: 246
`
`US 9,132,239 B2
`Page 2
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`20209051 Ul
`DE
`10237258 Al
`DE
`008160
`EA
`327910 A2
`EP
`0608343 Al
`EP
`615762
`EP
`897729 A2
`EP
`908273
`EP
`937476
`EP
`1768725 Al
`EP
`1909871 Al
`EP
`1926514 Al
`EP
`2373361 Al
`EP
`GB
`574705
`2008-528071 A
`JP
`2008-196696 A
`JP
`1804865
`PL
`2373361
`PL
`2254878 C2
`RU
`1528330 A3
`SU
`95/21645 Al
`WO
`02/50214 A2
`WO
`W002053214
`WO
`03/057285 A2
`WO
`2004054644 Al
`WO
`2005/102421 Al
`WO
`2006/003130 Al
`WO
`2006040296 A2
`WO
`2006045526 Al
`WO
`W02006045526
`WO
`2007021195 Al
`WO
`2007063342 Al
`WO
`2007104636 Al
`WO
`* cited by examiner
`
`4/2003
`3/2004
`4/2007
`g/1989
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`2/1999
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`g/1999
`4/2007
`4/2008
`6/2008
`10/2011
`1/1946
`7/2008
`g/2008
`10/2005
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`6/2005
`12/1989
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`.. ... ... .... ..
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`et al.
`
`.... .. 604/110
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`g/2010
`11/2011
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`12/2008
`g/2013
`
`AAAAAAAB
`
`l
`B2
`B2
`B2
`B2
`B2
`B2
`Al*
`Al
`Al
`Al
`Al
`Al
`Al*
`Al*
`Al
`Al*
`Al*
`
`4,998,922
`5,011,479
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`2013/0204197
`
`FOREIGN PATENT DOCUMENTS
`
`DE
`DE
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`
`29513214 Ul
`19838760 Al
`10103287 Al
`
`1/1997
`4/2000
`g/2001
`
`

`

`Case 1:22-cv-00023-JPB Document 2-7 Filed 03/18/22 Page 4 of 9 PageID #: 247
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`U.S. Patent
`
`Sep. 15, 2015
`
`Sheet 1 of 3
`
`US 9,132,239 B2
`
`34
`
`20
`
`30
`
`35
`
`32
`
`36
`
`13
`
`28
`
`10
`
`

`

`Case 1:22-cv-00023-JPB Document 2-7 Filed 03/18/22 Page 5 of 9 PageID #: 248
`
`U.S. Patent
`
`Sep. 15, 2015
`
`Sheet 2 of 3
`
`US 9,132,239 B2
`
`24
`
`25
`
`26
`
`36
`
`32
`
`21
`
`34
`
`27
`
`15
`
`14
`
`12
`
`10
`
`20
`
`10
`
`Fig. 3
`
`

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`Case 1:22-cv-00023-JPB Document 2-7 Filed 03/18/22 Page 6 of 9 PageID #: 249
`
`U.S. Patent
`
`Sep. 15, 2015
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`Sheet 3 of 3
`
`US 9,132,239 B2
`
`29
`
`24
`
`20
`
`27
`
`21
`
`25
`
`23
`
`28
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`22
`
`Fig. 4
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`32
`
`33
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`34
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`30
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`36
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`31
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`35
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`

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`Case 1:22-cv-00023-JPB Document 2-7 Filed 03/18/22 Page 7 of 9 PageID #: 250
`
`US 9, 132,239 B2
`
`1
`DIAL-DOWN MECHANISM FOR WIND-UP
`PEN
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`This application is a 35 U.S.C. )371 national
`stage appli-
`cation of International
`PCT/EP2009/
`Patent Application
`063801 (published as WO 2010/046394), filed Oct. 21, 2009,
`which claimed priority of European Patent Application EP
`08167547.2, filed Oct. 24, 2008; this application
`further
`claims priority under 35 U.S.C. )119 of U.S. Provisional
`Application 61/109,242, filed Oct. 29, 2008.
`
`5
`
`10
`
`THE TECHNICAL FIELD OF THE INVENTION
`
`15
`
`invention relates to a dial-down mechanism for
`The present
`automatic wind-up pens. In particular,
`the present
`invention
`dial-down mechanism for a torsion
`relates to an integrated
`spring assisted wind-up pen.
`
`DESCRIPTION OF RELATED ART
`
`In known injection devices, such as wind-up pens, based on
`torsion springs,
`the user usually strains the torsion spring by
`dose setting member of the injection
`a rotatable
`rotating
`device. The force thereby applied by the user is stored in the
`torsion spring for later release.
`An example of a known wind-up pen applying
`a torsion
`spring may for example be found in U.S. Pat. No. 5, 104,380.
`In this wind-up pen the dose setting member
`is located at the
`end and works such that when the user rotates the
`proximal
`dose setting member
`the spring is strained. The wind-up pen
`disclosed in U.S. Pat. No. 5, 104,380 has the disadvantage
`that
`if a user sets a dose to large it is not possible to decrease the set
`dose. The user
`then has to release the latch mechanism
`thereby expelling the entire set dose be fore a new correct dose
`can be set and delivered.
`Modern injection devices as the one e.g. disclosed in U.S.
`Pat. No. 6,004,297 has the possibility of rotating the dose
`in an opposite direction and thereby reduce
`setting member
`the set dose prior to deliverance of the set dose. Such mecha-
`nism is usually referred to as a dial-up/dial-down mechanism
`since it can both increase and decrease the set dose prior to
`inj ection.
`mechanism for a spring-loaded
`Such dial-up/dial-down
`injection pen is known from WO 02/053214.
`A wind-up pen based on a torsion spring and with a dial-
`up/dial-down mechanism is further disclosed in WO 2006/
`045526. The mechanism described in this document
`is based
`on a number of cam and key engagements. When working
`as in injection devices it has shown
`within small dimensions
`that such small dimensioned cam and key parts has a tendency
`or during use.
`to break during manufacture
`
`DESCRIPTION OF THE INVENTION
`
`It is an object of the present
`invention to provide a dial-
`down mechanism for automatic wind-up pens which is more
`to breakage.
`robust and less vulnerable
`The ratchet arm provided on the dose setting tube engages
`one or more teeth on the fixation element. Further
`the ratchet
`arm is provided with a radially extending knob or the like
`inwardly moves the ratchet arm out
`which when moved radial
`of its engagement with the fixation element. The knob on the
`ratchet arm is moved inwardly by a reset element provided on
`a reset tube. Once the reset element
`sweeps over the knob it
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`moves the ratchet arm inwardly. By having the reset element
`of the reset member work directly on the periphery of the
`knob and having the knob extend into the orbit described by
`each other can be
`the reset element
`small parts engaging
`avoided. The reset element can have many different shapes as
`arm out of
`long as it has the ability to move the ratchet
`engagement with the fixation element. Preferably the reset
`is a prolongation on the reset tube extending distally
`element
`part of the reset
`from the reset tube such that the predominant
`tube can be housed inside the dose setting tube but with the
`out of the dose setting tube. The
`reset element
`extending
`engagement between the knob ofthe ratchet arm and the reset
`is designed such that a relative rotation between these
`element
`two parts results in a inwardly radial movement ofthe ratchet
`arm which then is moved out of engagement with the teeth of
`the fixation element. The fixation element
`is preferably
`coupled to the housing of the injection device in a non-
`through engaging fins located on the exter-
`rotatable manner
`nal surface of the fixation element. These fins are rotational
`locked in similar grooves provided on the inside surface ofthe
`functionally working as a part of the
`housing or an element
`the fixation element can be moved axially
`housing, however
`out of its engagement with the housing and into an engage-
`force accu-
`ment with a drive element
`such that the torsional
`mulated in the torsion spring can be delivered to this drive
`in order to drive a liquid out of the injection device.
`element
`the reset element
`is rotated around the centre
`Preferably,
`axis of the injection pen with a constant
`radius while the
`ratchet arm has its knob extending beyond this diameter
`such
`the reset element can be brought
`that
`into engagement with
`the knob whereby the ratchet arm is moved out of engagement
`with the fixation element.
`the ratchet arm is provided with a steep surface on
`Further
`its free end which engages a steep surface of a tooth of the
`fixation element. When these two steep surfaces are brought
`out of engagement,
`the two elements can rotate relatively to
`each other.
`
`DEFINITIONS
`
`An "injection pen" is typically an injection apparatus
`or
`device having an oblong or elongated shape somewhat
`like a
`pen for writing. Although
`such pens usually have a tubular
`they could easily have a different cross-section
`cross-section,
`or square or any variation
`such as triangular,
`rectangular
`around these geometries.
`the term "medicament" or "drug" is meant
`As used herein,
`flowable medicine
`to
`encompass
`drug-containing
`any
`capable of being passed through a delivery means
`such as a
`solu-
`hollow needle in a controlled manner,
`such as a liquid,
`tion, gel or fine suspension. Representative
`includes
`drugs
`(e.g. insulin,
`insu-
`such as peptides, proteins
`pharmaceuticals
`and hormones,
`lin analogues
`biologically
`and C-peptide),
`derived or active agents, hormonal
`and gene based agents,
`in both solid (dis-
`and other substances
`formulas
`nutritional
`pensed) or liquid form.
`All references,
`including publications, patent applications,
`and patents, cited herein are incorporated by reference in their
`and to the same extent as if each reference were
`entirety
`and specifically indicated to be incorporated by
`individually
`reference and were set forth in its entirety herein.
`are used herein for conve-
`All headings
`and sub-headings
`nience only and should not be constructed
`as limiting
`the
`invention in any way.
`The use of any and all examples, or exemplary
`language
`(e.g. such as) provided herein,
`is intended merely to better
`the invention and does not pose a limitation on the
`illuminate
`
`

`

`Case 1:22-cv-00023-JPB Document 2-7 Filed 03/18/22 Page 8 of 9 PageID #: 251
`
`US 9, 132,239 B2
`
`scope ofthe invention unless otherwise claimed. No language
`should be construed as indicating
`in the specification
`any
`to the practice of the inven-
`non-claimed element as essential
`tion.
`The citation and incorporation of patent documents herein
`is done for convenience only and does not reflect any view of
`and/or enforceability of such patent
`the validity, patentability,
`documents.
`all modifications
`This invention includes
`and equivalents
`of the subject matter recited in the claims appended hereto as
`permitted by applicable law.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`The invention will be explained more fully below in con-
`and with reference to
`nection with a preferred embodiment
`in which:
`the drawings
`FIG. 1 Show an example of the dial-down mechanism.
`FIG. 2 Show a sectional view ofthe dial-down mechanism.
`FIG. 3 Show a view ofthe fixation element
`in a ring-shaped
`configuration.
`FIG. 4 Show a view of the ratchet
`tube.
`FIG. 5 Show a view of the reset tube.
`for clarity, and
`The figures are schematic
`and simplified
`to the understand-
`they just show details, which are essential
`ing of the invention, while other details are left out. Through-
`are used for identical or
`the same reference numerals
`out,
`parts.
`corresponding
`
`DETAILED DESCRIPTION OF EMBODIMENT
`
`as "upper" and "lower",
`When in the following
`terms
`"right" and "left", "horizontal" and "vertical", "clockwise"
`and "counter clockwise" or similar
`relative expressions
`are
`these only refer to the appended figures and not to an
`used,
`actual situation of use. The shown figures are schematic rep-
`for which reason the configuration of the differ-
`resentations
`are
`as well
`as
`there
`relative
`dimensions
`structures
`ent
`intended to serve illustrative purposes only.
`to define that the term
`it may be convenient
`In that context
`"distal end" in the appended figures
`to refer to the
`is meant
`end of the dial down mechanism including the ring shaped
`element 10 whereas the term "proximal end" is meant
`to refer
`to the opposite end pointing away from the ring shaped ele-
`ment 10.
`The dial down mechanism disclosed in FIG. 1 comprises of
`three parts, a fixation element or ring 10, a dose setting ele-
`tube 20 and a reset tube 30.
`ment or ratchet
`The ring 10 as disclosed in FIG. 3 has on its outside surface
`a number of engaging means such as fins 11by which the ring
`coupled to a not shown housing of an
`10 is non-rotatable
`injection device. The ring 10 could alternatively
`be attached
`to the housing in a number of different ways, however,
`as
`explained later the ring shaped element 10 must be able to
`move axially relatively to the housing.
`On its inside surface the ring 10 is provided with a plurality
`of teeth 12 which has a steep edge 13 in one direction and a
`sloped edge 14 in the opposite direction such that the ratchet
`arm 21 ofthe ratchet
`tube 20 is prevented from rotating in one
`is allowed to rotate in the opposite direction.
`direction but
`This is best seen in FIG. 2.
`tube 20 disclosed in details on FIG. 4 has on its
`The ratchet
`outer surface 22
`distal end a circular part with a peripheral
`that fits into the inside of the ring 10.This outer surface 22 is
`provided with a circular recess 23 which is engaged with a
`similar circular element 15 on the ring 10 such that the ring 10
`
`6
`
`10
`
`16
`
`20
`
`26
`
`30
`
`36
`
`40
`
`46
`
`60
`
`66
`
`60
`
`66
`
`tube 20 is locked to each other
`in the axial
`and the ratchet
`direction but can be rotated relatively to each other.
`The peripheral outer surface 22 is provided with a flexible
`in a steep surface 24. The
`ratchet arm 21 which terminates
`ratchet arm 21 is on its peripheral
`surface provided with an
`pointing protrusion 25 which opposite the steep
`outwardly
`surface 24 which steep surface 24 also incorporates
`the pro-
`trusion 25 has a sloped surface 26 which slopes down to the
`ratchet arm 21.
`tube 20 and the ring 10 is engaged as
`Once the ratchet
`disclosed in FIG. 1 the steep surface 24 of the ratchet arm 21
`engages the steep edge 13 on the ring 10 such that the ratchet
`tube 20 can only be rotated relatively to the ring 10 in one
`direction which in FIG. 1 is in the clockwise direction.
`tube 20 is engaged with a not shown torsion
`The ratchet
`spring which at its opposite end is connected to the housing of
`tube 20 is
`the injection device such that when the ratchet
`rotated in the clockwise direction
`(seen from a proximal
`the torsion spring is strained and is held in this
`position)
`between the steep sur-
`strained position by the engagement
`face 24 ofthe ratchet arm 21 and the steep edge 13 ofthe teeth
`12 on the ring 10.
`In this way a user can strain the torsion spring and thereby
`tube 20 relatively to the ring
`set a dose by rotating the ratchet
`10 in the clockwise direction and the described engagement
`24, 13 makes it impossible for the torsion spring to rotate back
`tube 20.
`the ratchet
`In order to provide a possibility for the user to dial down the
`In relation to FIG. 5 the
`set dose, a reset tube 30 is provided.
`reset tube 30 is provided with an extended portion 31 which
`has a forwardly pointing reset element 32 which follows the
`periphery of the extended portion 31.
`Once the injection device is assembled the reset tube 30 is
`tube 20 such that the reset element 32
`fitted inside the ratchet
`is located above the ratchet arm 21 as depictured in FIGS. 1
`and 2. In this position the axial engagement
`between the
`tube 20 and the reset tube 30 is secured by the protru-
`ratchet
`sion 33 of the reset
`in front of the front
`tube 30 engaging
`surface 29 of the ratchet
`tube 20.
`The extended portion 31 of the reset
`tube 30 is further
`provided with a first surface 34 in the clockwise direction and
`a second surface 35 in the anti-clockwise direction. Further,
`the reset element 32 is provided with a reset surface 36 in the
`anti-clockwise direction.
`The first surface 34 engages a similar dial-up surface 27 on
`tube 20 such that rotation of the reset tube 30 is
`the ratchet
`clockwise direction is trans formed directly to the ratchet
`tube
`tube 30 in the
`20 meaning
`that when a user dials the reset
`tube 20 follows
`clockwise direction to set a dose the ratchet
`this rotation and rotates relatively to the ring 10.
`The second surface 35 engages a spring element 2S urging
`the reset tube 30 in the clockwise direction whereas the reset
`surface 36 of the reset element 32 engages the sloped surface
`26 of the protrusion 25 of the ratchet arm 21.
`When setting a dose as explained above the user rotates the
`reset tube 30 which rotation is passed onto the ratchet
`tube 20
`which again is allowed to rotate relatively to the ring 10 in the
`clockwise direction thereby straining the torsion spring.
`When a user regrets the set dose and wants to decrease the
`tube 30 in the
`set dose this
`is done by rotating the reset
`as depictured in FIG.
`anti-clockwise direction. By doing so
`the reset surface 36 is pressed against
`2
`the sloped surface
`26 ofthe protrusion 25 which pulls the steep surface 24 out of
`engagement with the steep edge 13 of the teeth 12. This
`allows the torsion spring to be released and force the ratchet
`tube 20 in the anti-clockwise direction. Due to the size of the
`tube 20 will be
`torque stored in the torsion spring,
`the ratchet
`
`

`

`Case 1:22-cv-00023-JPB Document 2-7 Filed 03/18/22 Page 9 of 9 PageID #: 252
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`US 9, 132,239 B2
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`moved faster than the reset tube 30 whereby the sloped sur-
`face 26 of the protrusion 25 will no longer have the pressure
`ofreset surface 36 resting on it and the flexible ratchet arm 21
`will flex to its initial position and the steep surface 24 will
`engage the next steep edge 13 of the next
`teeth 12. By a
`rotation of the reset
`anti-clockwise
`tube 30, the
`continued
`steep surface 24 will move from teeth 12 to teeth 12 in a
`thereby lowering the torque stored in
`continued movement
`the torsion spring.
`Once the correct setting is obtained the torque stored in the
`torsion spring is released by axially moving the ring 10 out of
`the torsion spring
`engagement with the housing, whereby
`rotates back all three elements 10, 20, 30.
`have been shown in the fore-
`Some preferred embodiments
`going, but it should be stressed that the invention is not limited
`to these, but may be embodied
`in other ways within
`the
`subject matter defined in the following claims, e.g. could a
`needle assembly as herein described be delivered to the user
`in a rigid and sterile container which further could be shaped
`as a tool for assisting the user in mounting the needle assem-
`bly on to the injection device.
`The invention claimed is:
`1. A dial-down mechanism for an injection device com-
`prising a torsion spring which is strained when setting a dose
`by rotating a dose setting member
`(20) relatively to a housing
`and unstrained when rotating the dose
`in a first direction,
`(20) in a second direction opposite the first
`setting member
`the torsion spring for storing energy to expel a dose
`direction,
`from the injection device, the dial-down mechanism compris-
`ing:
`a fixation element (10) coupled to the housing and having
`a plurality of inwardly pointing teeth (12),
`at least one ratchet arm (21) coupled to the dose setting
`member
`(20),
`wherein the at least one ratchet arm (21) engages the teeth
`(12) of the fixation element (10) and is shaped such that
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`the dose setting member
`(20) is prevented from rotating
`arm (21)
`in the second direction when
`the ratchet
`engages the teeth (12) of the fixation element (10),
`the dial-down mechanism further comprises a reset mem-
`ber (30) configured for movement
`in a first direction and
`a second direction opposite the first direction,
`such that
`rotation of the reset member (30) in the first direction to
`directly to the dose setting
`set a dose is transformed
`(20) and thereby rotates relatively to the fixa-
`member
`tion element (10), and rotation of the reset member
`(30)
`in the second direction activates the ratchet arm (21) to
`(10) and thereby allow
`the fixation element
`disengage
`the dose setting member
`(20) to rotate in the second
`direction by carrying
`least one forward extending
`at
`(32) located distally to the reset member
`reset element
`(30) and which acts on at least one part (25) of the ratchet
`arm to move the ratchet arm (21)out ofengagement with
`the teeth (12)ofthe fixation element (10)thereby dialing
`down the set dose, wherein
`the reset member
`(30) is at least partially provided inside
`the dose setting tube (20) and axially retained by the
`dose setting member
`(20), and
`the ratchet arm (21) carries at
`least part (25) extending
`radially from the at least one ratchet arm (21) and having
`from the centre axis of the injection
`an outer
`radius
`device larger than the outer radius of the remaining part
`of the ratchet arm (21).
`2. A dial-down mechanism according to claim 1, charac-
`the reset element (32) travels along a constant
`terized in that,
`from the centre axis of the injection device when
`radius
`rotated.
`3. A dial-down mechanism according to claim 1, charac-
`the ratchet arm (21) is provided with a steep
`terized in that,
`surface (24) engaging a steep surface (13)of the teeth (12) of
`(10).
`the fixation element
`
`