United States Patent (19)
`Bendek et al.
`
`54 MEDICATION DELIVERY PEN HAVING AN
`IMPROVED CLUTCHASSEMBLY
`N.J.; Joh
`75 I
`: Antonio A. Bendek, V
`75 Inventors: Antonio A. Bendek, Vernon, N.J.; John
`E. Burbank, III, Ridgefield, Conn.;
`Charles L. Bush, Jr., Fairfield, N.J.;
`Jonathan B. Gabel, Randolph, N.J.;
`Lucio Giambattista, East Hanover,
`N.J.; Roger W. Hoeck, Loomis, Nebr.;
`Malcolm E. Taylor, Pepperell, Mass.
`73 Assignee: Becton Dickinson and Company,
`Franklin Lakes, N.J.
`
`21 Appl. No.: 08/909,222
`22 Filed:
`Aug. 11, 1997
`6
`51) Int. Cl. ...................................................... A61M 5700
`52 U.S. Cl. ........................... 604,207. 604211; 604.232
`58 Field of Search ............................ 604/207-211, 224,
`604/232, 152, 218
`
`56)
`
`Ref
`
`Cited
`CS
`
`U.S. PATENT DOCUMENTS
`4.568.335 2/1986 Updike et al. .......................... 604/211
`
`
`
`USOO592 1966A
`Patent Number:
`11
`(45) Date of Patent:
`
`5,921,966
`Jul. 13, 1999
`
`4,936,833 6/1990 Sams ................................... 604/208 X
`5,104,380 4/1992 Holman et al. ..................... 604/211 X
`5,279.585
`1/1994 Balkwill .................................. 604/207
`5,674,204 10/1997 Chanoch ............................. 604/232 X
`
`Primary Examiner Ronald Stright
`Assistant Examiner A. T. Nguyen
`Attorney, Agent, or Firm-Alan W. Fiedler
`57
`ABSTRACT
`
`An improved medication delivery pen is provided for inject
`ing fluids Such as insulin within body tissue. The medication
`delivery pen includes a mechanism that prevents the
`removal Of a cartridge unless an InlectOr button. On the
`1 of
`idge unl
`injector b
`h
`medication pen is in a predefined position, a bayonet attach
`ment and an improved clutch assembly in a dose setting
`mechanism that provides improved control over the torque
`necessary to rotate a units counter ring in the medication
`delivery pen using a dose Setting knob.
`
`7 Claims, 14 Drawing Sheets
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 1 of 20
`
`

`

`U.S. Patent
`
`Jul. 13,1999
`
`Sheet 1 of 14
`
`5,921,966
`
`A"
`
`CM
`
`C
`
`o
`
`o
`<N
`
`cn cs
`
`CD
`
`\
`
`00
`
`o
`
`p£-l
`
`O)
`
`<&>
`
`•
`
`O)
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 2 of 20
`
`

`

`U.S. Patent
`
`Jul. 13,1999
`
`Sheet 2 of 14
`
`5,921,966
`
`o -'•K) .
`
`i
`
`#
`
`CM
`
`CD
`CM
`
`(£>
`
`\JJ
`
`00
`
`\J2
`
`—-A
`
`O)
`
`o
`
`O
`
`O
`CM
`
`CV2
`O
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 3 of 20
`
`

`

`U.S. Patent
`
`Jul. 13,1999
`
`Sheet 3 of 14
`
`5,921,966
`
`CN
`
`C7)
`CN
`
`O
`CN
`
`CO
`
`\
`
`CM
`
`CNJ
`CN
`
`O
`
`CO
`
`o
`
`00
`
`cn
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 4 of 20
`
`

`

`U.S. Patent
`
`K
`
`Jul. 13,1999
`
`Sheet 4 of 14
`
`5,921,966
`
`CM
`
`***
`
`O
`<N
`
`CD
`
`CO
`CS
`
`o
`CO
`
`u
`CD
`CM
`
`o
`P^H
`
`"D
`CD
`CM
`
`\
`
`o
`CD
`CM
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 5 of 20
`
`

`

`U.S. Patent
`
`Jul. 13, 1999
`
`Sheet S of 14
`
`5,921,966
`
`
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 6 of 20
`
`

`

`U.S. Patent
`
`Jul. 13, 1999
`
`Sheet 6 of 14
`
`5,921,966
`
`
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 7 of 20
`
`

`

`U.S. Patent
`
`Jul. 13,1999
`
`Sheet 7 of 14
`
`5,921,966
`
`\ \ \
`\
`
`ro
`
`\
`
`\
`
`xt
`CM
`
`CO
`O
`
`(N
`
`O
`CM
`
`^ ^
`i v m
`
`J3
`m
`
`\ \
`
`ID
`
`o m
`
`o
`(£>
`K)
`
`\>
`
`\
`
`\ \
`\
`\
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 8 of 20
`
`

`

`Jul. 13,1999
`
`Sheet 8 of 14
`
`5,921,966
`
`U.S. Patent
`\ \ \
`
`CM
`
`ro ^
`
`^ 8
`
`ID
`
`O
`O to
`
`O
`00
`
`O
`O
`K)
`
`D
`to
`
`r. CN
`
`O
`ID
`CN
`O
`00
`
`XI
`00
`
`O
`CM
`
`z>
`I o
`
`ptH
`
`00
`
`I1
`
`S2
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 9 of 20
`
`

`

`U.S. Patent
`
`Jul. 13,1999
`
`Sheet 9 of 14
`
`5,921,966
`
`CM
`
`w'
`
`CM
`
`-o
`00
`<N
`
`O
`T- _Ci
`to T-
`K>
`
`ID
`
`\
`
`%
`
`\ \
`
`\
`
`\
`
`\
`
`\
`
`\
`
`\
`\
`
`oo
`
`\
`
`\
`
`A
`
`n
`
`ft
`
`to
`
`OD
`
`o
`
`pJH
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 10 of 20
`
`

`

`U.S. Patent
`
`Jul. 13, 1999
`
`Sheet 10 of 14
`
`5,921,966
`
`9 |
`
`97
`
`
`
`
`
`
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 11 of 20
`
`

`

`U.S. Patent
`
`Jul. 13, 1999
`
`Sheet 11 of 14
`
`5,921,966
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`0]-0IH
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 12 of 20
`
`

`

`U.S. Patent
`
`Jul. 13, 1999
`
`Sheet 12 of 14
`
`5,921,966
`
`fyz
`
`77
`
`zy º azyZ2
`
`kgzzzZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ
`(No.SSSSS9Z
`
`mí-----
`
`
`
`
`
`
`
`| |-0||||
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 13 of 20
`
`

`

`U.S. Patent
`
`Jul. 13,1999
`
`Sheet 13 of 14
`
`5,921,966
`
`S
`nrV/X
`
`\
`
`CD
`CS
`
`ro
`
`I S
`
`\
`\
`
`\
`\
`\
`V
`\
`
`o
`m
`
`o
`m
`
`TJ in
`
`CM
`
`%
`p^I
`% X
`-*1-
`K)
`S ^ %
`% z
`
`C\2
`I
`o
`
`Pt-I
`
`v/N
`" X N
`ry<
`
`CD
`
`s
`
`S
`
`SI
`
`CM
`
`\
`
`s
`\
`\
`
`\
`\
`
`— — -
`
`f
`
`s
`
`XI
`CD
`<N
`
`CN
`
`in
`y
`
`CD
`
`
`
`
`rai Hi
`^ I'?
`^ m
`K) m
`
`o
`•"t
`
`"*!•
`•<
`
`''t
`
`CM
`
`S<%
`
`CD
`CM
`
`$
`
`\
`\
`/ ^
`
`^
`
`N §
`
`s
`V
`
`
`^
`
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 14 of 20
`
`

`

`U.S. Patent
`
`Jul. 13, 1999
`
`Sheet 14 of 14
`
`5,921,966
`
`
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 15 of 20
`
`

`

`1
`MEDICATION DELIVERY PEN HAVING AN
`IMPROVED CLUTCHASSEMBLY
`
`5,921,966
`
`2
`cylindrical wall of the vial. This prior art medication deliv
`ery pen is used by inserting the Vial of medication into the
`Vial holder. A prior art pen body then is connected to the
`proximal end of the vial holder. The pen body includes a
`dose Setting apparatus for designating a dose of medication
`to be delivered by the pen and a driving apparatus for urging
`the plunger of the Vial distally for a distance corresponding
`to the Selected dose.
`The user of the pen mounts a prior art double-ended
`needle cannula to the distal end of the vial holder Such that
`the proximal point cannula of the needle cannula pierces the
`elastomeric Seal on the vial. The user then Selects a dose and
`operates the pen to urge the plunger distally to deliver the
`Selected dose. The user then removes and discards the needle
`cannula, and keeps the prior art medication delivery pen in
`a convenient location for the next required medication
`administration. The medication in the vial will become
`exhausted after Several Such administrations of medication.
`The user then separates the vial holder from the pen body.
`The empty vial may then be removed and discarded. A new
`vial can be inserted into the vial holder, and the vial holder
`and pen body can be reassembled and used again as
`explained above.
`The above described reusable medication delivery pen is
`effective and much more convenient for Self-administration
`of medication than the typical hypodermic Syringe and
`Separate medication vial. However, it has been found that
`there is the need for additional features and improvements
`for Such a medication delivery pen. For example, there is the
`need to prevent removal of the vial unless the injector button
`of the medication delivery pen is in a Selected position, to
`provide improved control over the torques available or
`necessary to rotate a unit indicator using a dose setting
`apparatus, and to generally Strengthen or otherwise improve
`the dose Setting apparatus in the mediation delivery pen.
`SUMMARY OF THE INVENTION
`The present invention is directed to providing a medica
`tion delivery pen having the features and improvements Set
`forth above.
`One object of the present invention is to provide a
`mechanism in the medication delivery pen that prevents the
`removal of a vial or cartridge unless the injector button of
`the medication pen is in a Selected position. The feature is
`provided by using a pair of bayonet connections on the
`cartridge retainer to activate a locking mechanism in the pen
`when the cartridge retainer is rotated. In particular, when the
`injector button is in the up position, the pivot shafts on the
`half-nuts in the pen prevent rotation of a locking sleeve
`which prevents removal of the cartridge retainer and car
`tridge. However, when the injector button is in the down
`position the pivot shafts on the half nuts in the pen do not
`prevent rotation of the locking sleeve, which then allows the
`cartridge retainer to rotate and the bayonet connections to be
`Separated from the pen's housing to remove the cartridge.
`Another object of the present invention is to improve the
`clutch assembly in the medication delivery pen to provide
`more control over the torques necessary to rotate the unit
`indicator in the pen using the rotation of a dosing knob in the
`dose Setting apparatus.
`A third object of the present invention is to improve the
`dose dispensing apparatus to provide more definite control
`over the dose dispensing operation by preventing skewing of
`the drive mechanism.
`These and other aspects, features and advantages of the
`present invention will become apparent from the following
`
`BACKGROUND OF THE INVENTION
`1. Field of the Invention
`The Subject invention relates to an improved medication
`delivery pen.
`2. Description of Related Art
`Hypodermic Syringes are used to deliver Selected doses of
`medication to patients. The prior art hypodermic Syringe
`includes a Syringe barrel having opposed proximal and distal
`ends. A cylindrical chamber wall extends between the ends
`and defines a fluid receiving chamber. The proximal end of
`the prior art Syringe barrel is Substantially open and receives
`a plunger in Sliding fluid tight engagement. The distal end of
`the prior art Syringe barrel includes a passage communicat
`ing with the chamber. A needle cannula may be mounted to
`the distal end of the prior art Syringe barrel, Such that the
`lumen of the needle cannula communicates with the passage
`and the chamber of the syringe barrel. Movement of the
`plunger in a proximal direction draws fluid through the
`lumen of the needle cannula and into the chamber. Move
`ment of the plunger in a proximal-to-distal direction urges
`fluid from the chamber and through the lumen of the needle
`cannula.
`Medication to be injected with the prior art hypodermic
`Syringe often is Stored in a vial having a pierceable elasto
`meric Seal. Medication in the prior art vial is accessed by
`piercing the elastomeric Seal with the needle cannula. A
`Selected dose of the medication may be drawn into the
`chamber of the Syringe barrel by moving the plunger a
`Selected distance in a proximal direction. The needle cannula
`may be withdrawn from the vial, and the medication may be
`injected into a patient by moving the plunger in a distal
`direction.
`Some medication, Such as insulin is Self-administered.
`The typical diabetes patient will require injections of insulin
`Several times during the course of a week or day. The
`required dose of insulin will vary from patient to patient, and
`for each patient may vary during the course of the day and
`from day to day. Each diabetes patient will establish a
`regimen that is appropriate for his or her own medical
`condition and for his or her lifestyle. The regimen typically
`includes Some combination of a slow or medium acting
`insulin and a faster acting insulin. Each of these regimens
`may require the diabetes patient to periodically Self
`administer insulin in public locations, Such as places of
`employment or restaurants. The required manipulation of
`the Standard prior art hypodermic Syringe and vial can be
`inconvenient and embarrassing in these public environ
`mentS.
`Medication delivery pens have been developed to facili
`tate the Self-administration of medication. One prior art
`medication delivery pen described in U.S. Pat. No. 5.279,
`585 includes a vial holder into which a vial of insulin or
`other medication may be received. The vial holder is an
`elongate generally tubular structure with proximal and distal
`ends. The distal end of the prior art vial holder includes
`mounting means for engaging a double-ended needle can
`nula. The proximal end also includes mounting means for
`engaging a driver and dose Setting apparatus as explained
`further below. A disposable vial for use with the prior art vial
`holder includes a distal end having a pierceable elastomeric
`Seal that can be pierced by one end of a double-ended needle
`cannula. The proximal end of this prior art vial includes a
`plunger slidably disposed in fluid tight engagement with the
`
`15
`
`25
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 16 of 20
`
`

`

`3
`detailed description taken in conjunction with the accom
`panying drawings.
`
`DESCRIPTION OF THE DRAWINGS
`FIG. 1 is a perspective view of a medication delivery pen
`of the Subject invention;
`FIG. 2 is a perspective view of the medication delivery
`pen shown in FIG. 1 with the plunger extended;
`FIG. 3 is a perspective view of the medication delivery
`pen shown in FIG. 1 with the plunger moving axially during
`an injection;
`FIG. 4 is a perspective view of the medication delivery
`pen shown in FIG. 1 with the cartridge retainer removed;
`FIGS. 5a and 5b are exploded perspective views of the
`pen shown in FIG. 1 further including a needle assembly;
`FIG. 6 is an enlarged perspective of the clutch assembly;
`FIG. 7 is an exploded perspective view of the medication
`delivery pen shown in FIG. 1 with the cartridge retainer
`removed;
`FIG. 8 is another perspective view of the medication
`delivery pen shown in FIG. 1 with the cartridge retainer
`attached and locked onto the upper body;
`FIG. 9 is a cross sectional view taken along lines 9-9 as
`shown in FIG. 1;
`FIG. 10 is a cross sectional view taken along lines 10-10
`as shown in FIG. 2;
`FIG. 11 is a cross sectional view taken along lines 11-11
`as shown in FIG. 4;
`FIG. 12 is an enlarged cross sectional view of the medi
`cation delivery pen shown in FIGS. 2 and 10 to more clearly
`show the clutch assembly;
`FIG. 13 is an enlarged cross sectional view of the Zero
`detection clip shown in FIG. 5b, and
`FIG. 14 is a cross sectional view taken along lines 14-14
`as shown in FIG. 13.
`
`DETAILED DESCRIPTION
`An improved injection device 10 for injecting insulin or
`other medication is provided by the present invention. AS
`shown in FIGS. 1-3, the device includes an adjusting knob
`12, an upper body 14, a center body 16, and a cartridge
`retainer 18. All of these elements have a generally cylindri
`cal configuration and are arranged coaxially to define a
`generally cylindrical housing 20 which can easily be
`handled by a patient or medical attendant.
`Referring to FIGS. 4,5a and 7-12, a plunger 22 is at least
`partially positioned within the portion of housing 20 defined
`by adjusting knob 12, upper body 14 and center body 16.
`Plunger 22 includes a hollow, Substantially cylindrical body
`22a including a band of radially projecting Splines 22b
`extending outwardly therefrom. A pair of opposing projec
`tions 22c extend radially inwardly from the front end of the
`cylindrical body 22a. As shown in FIGS. 5a and 5b, the rear
`end of plunger 22 is Secured to a hub 25 having a rotatable
`push button 24 Snapped therein. Push button 24 fits partially
`within adjusting knob 12 when plunger 22 is fully inserted
`within housing 20.
`A lead screw 26 is positioned within and coaxially with
`plunger 22 and includes an enlarged front end 26a and a
`tapered rear end 26b, connected by an elongate threaded
`body 26c. A pair of longitudinal grooves 26d are formed
`within threaded body 26c and receive the radially inwardly
`extending projections 22c of plunger 22. Lead Screw 26 is
`
`15
`
`25
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`5,921,966
`
`4
`accordingly rotatable with plunger 22 and capable of Sliding
`axially with respect to plunger 22.
`A pair of half-nuts 28 are positioned within center body
`16, with each half-nut 28 including a semi-cylindrical body
`portion 28a and a radially enlarged end portion 28b. The
`front end of each half-nut 28 includes threads 28c that are
`used to threadably engage with lead Screw 26 and the rear
`end of each half-nut 28 includes a pivot shaft 28d that
`receives a metal pin 28e to provide an axis about which each
`half-nut 28 can pivot. Metal pins 28e inserted in each pivot
`shaft 28d also provide more definite control over the dose
`Setting operation, described below, and prevent skewing of
`half nuts 28 on threaded lead screw 26. Body portions 28a
`of half-nuts 28 are positioned at least partially within a
`locking ring 30 having a hollow, generally cylindrical body
`portion 30a defining a generally elliptical passage 30e for
`receiving half-nuts 28. A front end 30b of locking ring 30 is
`radially enlarged and includes a pair of angular projections
`30c that extend axially from the front end of locking ring 30
`and the side of locking ring 30 includes a pair of pins 30d.
`The proximal end 18b of cartridge retainer 18 includes a pair
`of angular projections 18c that are Spaced to receive angular
`projections 30c when cartridge retainer 18 is mounted on
`housing 20, which is described further below.
`A helical coil Spring 32 is positioned over locking ring 30
`and half-nuts 28 and through locking sleeve 31, with one end
`of coil Spring 32 bearing against the radially enlarged
`portions 28b of half-nuts 28 while the opposite end of coil
`spring 32 bears against the radially enlarged front end 30b
`of locking ring 30. Front end 30b of locking ring 30 mounts
`within center body 16 which also receives finishing ring 29.
`The rear end portion 28b of half-nuts 28 abut splines 22b of
`plunger 22, as shown in FIG. 9.
`Locking ring 30 is slidably mounted within locking sleeve
`31 such that the pair of pins 30d on locking ring 30 are
`mounted and travel within slot 31a at a distal end of locking
`sleeve 31. With this structure locking ring 30 is axially
`movable within locking sleeve 31 but rotates with locking
`sleeve 31. Locking sleeve 31 also includes a pair of
`L-shaped grooves 31b that slidably receive each of the shafts
`28d on half-nuts 28. Each pivot shaft 28d in conjunction
`with its respective L-shaped groove 31b on locking sleeve
`31 and a long groove 16c within center body 16 provides a
`mechanism that prevents the removal of cartridge retainer 18
`and cartridge 46 from housing 20, unless injector button 24
`is in a down or loading position. This feature is more clearly
`shown in FIGS. 7 and 8. In FIG. 7 injector button 24 is in
`the down or loading position and device 10 is in the proper
`position for receiving cartridge retainer 18 and, in particular,
`lugs 18a can enter slot 16a of center body 16. As shown in
`FIG. 7, locking ring 30 is oriented so that tabs 30c do not
`block access to slot 16a and in this orientation pivot shafts
`28d of half-nuts 28 are located in notches 31e at the end of
`each lower leg 31d of L-shaped groove 31b. After a cartridge
`46 has been loaded into cartridge retainer 18, cartridge
`retainer 18 is mated with center housing 16 Such that lugs
`18a enter slot 16a. Then, as shown in FIG. 8, cartridge
`retainer 18 is rotated in a clockwise direction Such that lugs
`18a drive tabs 30c in a clockwise direction which moves
`locking sleeve 31 and causes pivot shaft 28d to slide out of
`each notch 31e and into each leg 31d of each L-shaped
`groove 31b. At this point, spring 32 drives half-nuts 28 in the
`proximal direction to extend injector button 24 from the
`proximal end of assembly 10, if dose settings rings 36 and
`38 are set to zero.
`As shown in FIG. 5b, upper body 14 includes an opening
`14a in which a transparent window 34 is mounted. A units
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 17 of 20
`
`

`

`S
`counter ring 36 and a tens counter ring 38 are positioned in
`adjoining relation beneath window 34, with both counter
`ringS 36 and 38 including Outer Surfaces having numerals
`thereon visible through window 34.
`An O-ring 40 made from an elastomeric material is
`mounted in units counter ring 36 to hold a transmission key
`44 in position. Transmission key 44 is provided for engaging
`and disengaging the units and tens counter ringS 36, 38, and
`is located within a channel formed in units counter ring 36,
`as shown in FIG. 12. A zero detection clip 42, more clearly
`shown in FIGS. 13 and 14, is positioned between the inner
`surfaces of counter rings 36 and 38 and the outer surface of
`plunger 22. Zero detection clip 42, as shown in FIGS. 5b, 13
`and 14, includes a generally cylindrical body 42a having a
`radially enlarged front end 42b. A lower spring member 42c
`extends axially within a slot formed within clip body 42a
`and includes a ridge 42d that is engageable with groove 38a
`formed within the inner surface of tens counter ring 38, as
`best shown in FIG. 14. Zero detection clip 42 also includes
`an axially extending upper Spring member 42e, the position
`of which is controlled by the rotational positions of the units
`and tens counter rings 36, 38. Upper Spring member 42e
`includes a distal Surface 42f that is engageable with Splines
`22b of plunger 22 when pushed into its active position by
`units counter ring 36 or by tens counter ring 38. The inner
`Surface of units counter ring 36 functions as a cam and
`controls the radial position of upper Spring member 42e of
`the Zero detection clip 42.
`The inner Surface of units counter ring 36 is splined, with
`the Spline Surface being engageable with Small Splines 22d
`of plunger 22. Engagement between ring 36 and plunger 22
`occurs when Spring 32 is in the extended position shown in
`FIG. 10. Units counter ring 36 is then driven by adjusting
`knob 12 through a specially designed clutch detent Spring
`15, more clearly shown in FIG. 6. Clutch detent spring 15
`includes a ring 15a having four internal tabs 15b that mount
`ring 15a onto units counter ring 36 and four legs 15c that are
`driven by rotation of adjusting knob 12. The present inven
`tion provides a clutch detent Spring 15 that is made of a
`flexible metal that can be manufactured to provide a prede
`termined slip torque action between adjusting knob 12 and
`units counter ring 36.
`FIG. 6 is an enlarged perspective view of clutch detent
`Spring 15 and shows its connection with adjusting knob 12,
`clutch nut 13 and units counter ring 36. Clutch detent Spring
`15 includes ring 15a having four outer legs 15c extending in
`the distal direction with each leg 15c having a protrusion 15d
`thereon extending away from rotational axis 15r of clutch
`detent spring 15. Internal tabs 15b correspond to notches 36a
`on units counter ring 36 that receive a respective internal tab
`15b and hold clutch detent spring 15 onto units counter ring
`36 together with the clutch nut 13 that is threaded onto units
`counter ring 36. When units counter ring 36 with clutch
`detent Spring 15 mounted thereon is assembled into adjust
`ing knob 12, protrusions 15d on clutch detent spring 15 mate
`with inner Surface 12a of adjusting knob 12 and travel in
`detents 12b on inner Surface 12a until a predetermined
`torque is encountered by units counter ring 36 which then
`causes clutch detent Spring 15 to rotate with respect to
`adjusting knob 12. The important feature of the present
`invention is that when the clutch detent Spring 15 is manu
`factured with angle 0 of each outer leg 15c with respect to
`rotational axis 15r, the clutch detent spring 15 is preset to
`provide release from adjusting knob 12 at a predetermined
`torque.
`As shown in FIG. 5a, cartridge retainer 18 is adapted for
`receiving a cartridge 46 of the type including an internal
`
`15
`
`25
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`5,921,966
`
`6
`piston 46b and a pierceable seal 46a at one end thereof. A
`threaded end cap 19 is inserted through cartridge retainer 18
`to extend from a distal end 18d of cartridge retainer 18 and
`is provided with threads 19a for securing a double ended
`needle assembly 50. The proximal end of cartridge retainer
`18 includes the pair of bayonet lugs 18a on angular projec
`tions 18c that engage with the pair of slots 16a at the distal
`end of center body 16.
`Needle assembly 50 includes a cannula 50a having a
`sharp distal end 50b for piercing the skin of a patient or user
`and a sharp proximal end 50c for piercing pierceable Seal
`46a of cartridge 46 with a lumen (not shown) therethrough.
`Needle assembly 50 includes a cup-shaped hub 50d holding
`cannula 50a So that sharp proximal end 50c projects out
`wardly from the interior of cup-shaped hub 50d. Cup-shaped
`hub 50d includes an internal thread that is compatible with
`thread 19a on end cap 19, so that needle assembly 50 may
`be removably attached to end cap 19 with its sharp proximal
`end 50c piercing pierceable seal 46a to establish fluid
`communication with the interior of cartridge 46.
`The operation of the injection device 10 shall now be
`described with reference to the accompanying figures. Gen
`erally Speaking, cartridge 46 is loaded within the device, and
`a double ended needle assembly 50 is affixed to the end of
`cartridge retainer 18. Fluid communication is accordingly
`established between the injection portion of double ended
`needle assembly 50 and the interior of cartridge 46. Once the
`appropriate dosage is Set, push button 24 is urged forwardly,
`causing lead Screw 26 to exert force upon piston 46b
`movably positioned within cartridge 46. Piston 46b dis
`places fluid within cartridge 46, causing its injection into
`body tissue through double ended needle assembly 50. The
`Specific functions which are performed using the injection
`device are described Separately herein. ASSuming the device
`is loaded and push button 24 is in the down position, three
`StepS are followed in the injection procedure: Set to Zero, Set
`the dose, and make the injection.
`First, adjusting knob 12 is rotated back to the Zero Setting
`on both counter rings 36 and 38. As will be described in
`more detail hereinbelow, adjusting knob 12 turns clutch
`detent spring 15 which then turns units counter ring 36.
`Because the Splines on units counter ring 36 and plunger 22
`are disengaged plunger 22 and the lead Screw 26 do not turn.
`When rings 36 and 38 reach Zero, their slots align and
`release upper Spring member 42e of Zero detection clip 42.
`This in turn releases plunger 22 and push button 24 which
`move under pressure from spring 32 via the two half nuts 28
`until the proximal ends of large Splines 22b of plunger 22 are
`Stopped by an inner Surface of units counter ring 36. This
`movement also carries lead Screw 26. Small Splines 22d on
`the plunger 22 engage with the Splined units counter ring 36
`and are ready for Setting a dose.
`Adjusting knob 12 is then rotated away from the Zero (0)
`Setting. Adjusting knob 12 turns clutch detent Spring 15,
`which turns units counter ring 36, which turns plunger 22.
`Plunger 22 is engaged with longitudinal grooves 26d in lead
`Screw 26 which turns and Screws forward in the nut formed
`by the two half nuts 28. The lead screw's travel is propor
`tional to the number of units displayed by the counter rings
`36, 38.
`When the desired dose has been set, push button 24 is
`pushed fully in which pushes plunger 22, two half nuts 28,
`and lead screw 26 forwards. Plunger and lead screw 26, as
`coupled by half nuts 28, accordingly perform the function of
`a piston rod. The total travel is determined by push button 24
`that Slides into and is Stopped by adjusting knob 12. The first
`
`PFIZER, INC. v. SANOFI-AVENTIS DEUTSCHLAND GMBH
`
`Ex. 1022, p. 18 of 20
`
`

`

`7
`part of the travel brings the end of lead screw 26 into contact
`with piston 46b of cartridge 46; the second part of the travel
`moves piston 46b of cartridge 46 forward and delivers the
`measured amount of medication. While Setting the dose,
`lead Screw 26 is moved forward in proportion to the dosage
`Set; this distance determines the proportion of the pre
`injection and injection travel. Plunger 22 and pushbutton 24
`are locked in position by upper Spring member 42e of the
`Zero detection clip 42 following an injection.
`When a dose is Set, units counter ring 36 pushes upper
`Spring member 42e of Zero detection clip 42 into its active
`position. Zero detection clip 42 includes a clicker 42g that
`generates a click for each unit as it passes over larger Splines
`22b on plunger 22. Units counter ring 36 drives the tens
`counter ring 38 through 36 degrees of rotation every time
`units counter ring 36 passes Zero via transmission key 44.
`Lower Spring member 42e of Zero detection clip 42 has a
`ridge 42d which engages with the grooves 38a inside the
`tens counter ring 38 and creates a click every time the tens
`counter ring 38 turns.
`If the dose is set at the maximum dialable dose
`(hereinafter “TMDD”), tens counter ring 38 reaches a stop,
`and transmission key 44 engages in the last location in the
`tens counter ring 38. If adjusting knob 12 is turned further,
`rings 36 and 38 are unable to turn and adjusting knob 12
`slips without further effect. Clutch detent spring 15 is
`designed to limit the torque which will be transmitted to the
`counter rings and prevents unintentional damage.
`The travel of lead screw 26 is limited to the safe travel of
`piston 46b in the cartridge 46. If lead screw 26 reaches the
`end of its travel, projections 22c inside plunger 22 reach the
`end of grooves 26d in lead screw 26 and prevent it from
`further movement. Lead Screw 26 prevents plunger 22 and
`counterrings 36 and 38 from turning. Adjusting knob 12 will
`then cause clutch detent spring 15 to slip without further
`effect. The counter rings will indicate the travel of the lead
`Screw to this point, and therefore, the quantity of insulin
`remaining in the cartridge.
`When adjusting knob 12 is rotated away from the Zero (0)
`Setting, and there are more than TMDD units remaining in
`cartridge 46, the counter rings will stop at TMDD units as
`described above. If there are less than TMDD units
`remaining, the counter rings will Stop as described above
`and display the remaining capacity of cartridge 46. In either
`case, the user can then turn adjusting knob 12 back until the
`counter rings display the dose to be administered.
`After a complete injection has been made, push button 24
`can be left in the loading position. AS described above, when
`device 10 is in the loading position cartridge retainer 18 can
`be removed from center body 16 of housing 20 and cartridge
`46 can be removed. When cartridge retainer 18 is removed
`from housing 20, the elliptical shape defined by the inner
`wall of locking ring 30 allows two half nuts 28 to open under
`preSSure from Spring 32 and to free lead Screw 26, as shown
`in FIG. 11.
`A new cartridge 46 can then be inserted into cartridge
`retainer 18 which is then locked back onto center body 16
`using the bayonet or lugs 18a on cartridge retainer 18. AS
`cartridge retainer 18 moves towards center body 16, piston
`46b of cartridge 46 will push lead screw 26 into the device.
`Cartridge retainer 18 has two angular projections 18c that
`engage with angular projections 30c extending from locking
`ring 30. When cartridge retainer 18 is then rotated the
`projections 18c and 30c cause locking ring 30 to turn the
`Same amount. In addition, after cartridge retainer 18 has
`rotated and each lug 18a on cartridge retainer 18 has entered
`
`15
`
`25
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`5,921,966
`
`8
`its respective recess 16b in slot 16a inside center body 16,
`cartridge retainer 18 is prevented from turning further. The
`elliptical inner wall of locking ring 30 moves two half nuts
`28 into engagement with lead screw 26. The position of lead
`screw 26 is then determined by the position of the piston 46b
`in cartridge 46.
`Upper body 14 houses the four parts which comprise the
`counter mechanism. Window 34 in upper body 14 shows the
`numbers printed on the outside of the two counter rings 36
`and 38, and indicates the number of units to be injected from
`0 to TMDD. Units counter ring 36 is turned by adjusting
`knob 12 through clutch detent spring 15. When units counter
`ring 36 has turned to numbered position “8”, transmission
`key 44 meets the cam molded inside upper body 14. The
`transmission key 44 is then forced to slide up the face of the
`cam, and reaches the top in position “9”. The elastic ring 40
`is flexed by this movement and maintains the transmission
`key 44 in contact with the cam. This movement also brings
`the opposite end of transmission key 44 into engagement
`with one of the slots 38b inside the tens counter ring 38,
`shown in FIG. 5b. When units counter ring 36 is turned
`further, transmission key 44 transmits the movement to tens
`counter ring 38, and the two rings turn together. At position
`“10” the window 34 now displays “10” and transmission key
`44