c12) United States Patent
`Moberg
`
`I 1111111111111111 11111 lllll lllll 111111111111111 lllll 111111111111111 11111111
`US006248093I31
`US 6,248,093 Bl
`Jun.19,2001
`
`(10) Patent No.:
`(45) Date of Patent:
`
`(54) COMPACT PUMP DRIVE SYSTEM
`
`(75)
`
`Inventor: Sheldon Moberg, Granada Hills, CA
`(US)
`
`(73) Assignee: MiniMed Inc., Northridge, CA (US)
`
`( *) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by O days.
`
`(21) Appl. No.: 09/429,352
`
`(22) Filed:
`
`Oct. 28, 1999
`
`Related U.S. Application Data
`( 60) Provisional application No. 60/106,237, filed on Oct. 29,
`1998.
`
`Int. Cl.7 ...................................................... A61M 5/00
`(51)
`(52) U.S. CI. ................... 604/131; 604/151; 128/DIG. 12
`(58) Field of Search ..................................... 604/131, 151,
`604/154, 155; 128/DIG. 1, DIG. 12, DIG. 13
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`D. 347,894
`D. 380,262
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`3,701,345
`4,084,588
`4,267,836
`4,444,546
`4,468,221
`4,562,751
`4,576,211
`4,601,491
`4,619,646
`4,678,408
`4,685,903
`4,744,790
`4,747,824
`4,749,109
`4,952,205
`5,080,653
`5,097,122
`
`6/1994 Hansen et al. .
`6/1997 Van Funderburk et al.
`11/1971 Heilman et al. .
`10/1972 Heilman el al..
`4/1978 Koenig.
`5/1981 Whitney et al. .
`4/1984 Pazemenas.
`8/1984 Mayfield.
`1/1986 Nason et al..
`3/1986 Valentini et al. .
`7/1986 Bell, Jr. et al. .
`10/1986 Hernandez et al. .
`7/1987 Nason et al..
`8/1987 Cable ct al..
`5/1988 Jankowski el al. .
`5/1988 Spinello.
`6/1988 Kamen.
`8/1990 Mauerer et al. .
`1/1992 Voss et al. .
`3/1992 Colman et al..
`
`5,121,019
`5,219,099
`5,254,096
`5,292,306
`5,389,078
`5,505,709
`5,545,152
`5,549,574
`5,554,134
`5,599,323
`5,611,785
`5,637,095
`5,647,853
`5,722,545
`5,779,675
`5,947,935
`
`6/1992 Pradier.
`6/1993 Spence et al. .
`10/1993 Rondelet et al. .
`3/1994 Wynkoop et al. .
`2/1995 Zalesky et al. .
`4/1996 Funderburk et al. .
`8/1996 Funderburk et al. .
`8/1996 Townsend.
`9/1996 Bonnichsen .
`2/1997 Bonnichscn ct al. .
`3/1997 Mito el al..
`6/1997 Nason et al. .
`7/1997 Feldmann et al. .
`3/1998 Rinne.
`7/1998 Reilley et al..
`9/1999 Rhinehart et al. .
`
`FOREIGN PATENT DOCUMENTS
`
`2240694
`0544653
`9800157
`
`8/1972 (DE) .
`1/1989 (EP) .
`10/1998 (WO) .
`
`OTHER PUBLICATIONS
`
`PCT Application PCT/US99/25414, Search Report mailed
`Feb. 2, 2000.
`PCT Application PCT/US99/25413, Search Report mailed
`Mar. 7, 2000.
`
`Primary Examiner-John D. Yasko
`(74) Attorney, Agent, or Firm---MiniMed Inc.
`
`(57)
`
`ABSTRACT
`
`An improved pump is provided for controlled delivery of
`fluids wherein the pump includes a reservoir and a movable
`piston. A plunger slide is in removable contact with the
`movable piston. A motor, is operably coupled to a drive
`member, such as a drive screw. The motor is disposed in-line
`with the drive member and the plunger slide. The drive
`member is operably connected to the plunger slide and is
`disposed to be substantially enclosed by the plunger slide
`when the plunger slide is in at least one position. The drive
`member is adapted to advance the plunger slide in response
`to operation of the motor.
`
`26 Claims, 14 Drawing Sheets
`
`401
`
`m/
`
`411
`
`411
`
`41D
`
`Sanofi Exhibit 2171.001
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun.19,2001
`
`Sheet 1 of 14
`
`US 6,248,093 Bl
`
`=
`
`= =
`
`Sanofi Exhibit 2171.002
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun.19,2001
`
`Sheet 2 of 14
`
`US 6,248,093 Bl
`
`...... = ""
`
`Sanofi Exhibit 2171.003
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun.19,2001
`
`Sheet 3 of 14
`
`US 6,248,093 Bl
`
`306
`
`302
`
`305
`
`flG. 3a
`
`flG. 3b
`
`Sanofi Exhibit 2171.004
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun.19,2001
`
`Sheet 4 of 14
`
`US 6,248,093 Bl
`
`= = _,_
`
`Sanofi Exhibit 2171.005
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun.19,2001
`
`Sheet 5 of 14
`
`US 6,248,093 Bl
`
`Sanofi Exhibit 2171.006
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun.19,2001
`
`Sheet 6 of 14
`
`US 6,248,093 BI
`
`CV-:, = --
`
`-= c:c,
`
`Sanofi Exhibit 2171.007
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun.19,2001
`
`Sheet 7 of 14
`
`US 6,248,093 Bl
`
`= = --
`
`Sanofi Exhibit 2171.008
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun. 19, 2001
`
`Sheet 8 of 14
`
`VS 6,248,093 Bl
`
`Sanofi Exhibit 2171.009
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun.19,2001
`
`Sheet 9 of 14
`
`US 6,248,093 Bl
`
`422
`
`flG. 8
`
`Sanofi Exhibit 2171.01 0
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun.19,2001
`
`Sheet 10 of 14
`
`US 6,248,093 Bl
`
`,.._ = =
`
`= = =
`
`Sanofi Exhibit 2171.011
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun.19,2001
`
`Sheet 11 of 14
`
`US 6,248,093 Bl
`
`605
`
`SYRINGf COMPARTMfNT
`
`flG. l Oa
`
`f IG. l Ob
`
`flG. l Oc
`
`605
`
`605
`
`401
`
`401
`
`401
`
`Sanofi Exhibit 2171.012
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun.19,2001
`
`Sheet 12 of 14
`
`US 6,248,093 Bl
`
`406
`
`405
`
`436
`
`426
`430
`
`442
`
`f I G. 11
`
`Sanofi Exhibit 2171.013
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun.19,2001
`
`Sheet 13 of 14
`
`US 6,248,093 Bl
`
`Sanofi Exhibit 2171.014
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent
`
`Jun.19,2001
`
`Sheet 14 of 14
`
`US 6,248,093 Bl
`
`HIGH mm
`
`lOW rORCE
`
`HIGH rnm CONOITION
`✓
`
`f□ RCE
`
`0
`
`f□ RCf
`
`a
`
`L STARTS ENGAGING fl AST r□□TH
`
`lOW mm '
`
`□ISPlACEMENT
`
`flG. 13a
`
`HAT CROSS THRfA□ f□ RCE
`
`I
`
`DISPlACEMENT
`
`flG. 13b
`
`SU DE BOTTO MS OUT
`IN PlUNGrn
`
`I
`
`Sll □ E BOTTOMS OUT
`IN PlUNGrn
`
`Sanofi Exhibit 2171.015
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`1
`COMPACT PUMP DRIVE SYSTEM
`
`US 6,248,093 Bl
`
`This application claims priority from provisional patent
`application No. 60/106,237, filed Oct. 29, 1998 and which is
`incorporated herein by reference.
`BACKGROUND OF THE INVENTION
`1. Field of the Invention
`This invention relates generally to improvements in infu(cid:173)
`sion pumps such as those used for controlled delivery of
`medication to a patient. More specifically, this invention
`relates to an improved infusion pump having a modified and
`space-efficient drive system.
`2. Description of the Related Art
`Infusion pump devices and systems are relatively well(cid:173)
`known in the medical arts, for use in delivering or dispens(cid:173)
`ing a prescribed medication such as insulin to a patient. In
`one form, such devices comprise a relatively compact pump
`housing adapted to receive a. syringe or reservoir carrying a
`prescribed medication for administration to the patient
`through infusion tubing and an associated catheter or infu(cid:173)
`sion set.
`The infusion pump includes a small drive motor con(cid:173)
`nected via a lead screw assembly for motor-driven advance(cid:173)
`ment of a reservoir piston to administer the medication to the
`user. Programmable controls can operate the drive motor
`continuously or at periodic intervals to obtain a closely
`controlled and accurate delivery of the medication over an
`extended period of time. Such infusion pumps are utilized to
`administer insulin and other medications, with exemplary 30
`pump constructions being shown and described in U.S. Pat.
`Nos. 4,562,751; 4,678,408; 4,685,903; 5,080,653 and 5,097,
`122, which are incorporated by reference herein.
`Infusion pumps of the general type described above have
`provided significant advantages and benefits with respect to 35
`accurate delivery of medication or other fluids over an
`extended period of time. The infusion pump can he designed
`to be extremely compact as well as water resistant, and may
`thus be adapted to be carried by the user, for example, by
`means of a belt clip or the like. As a result, important 40
`medication can be delivered to the user with precision and
`in an automated manner, without significant restriction on
`the user's mobility or life-style, including in some cases the
`ability to participate in water sports.
`These pumps often incorporate a drive system which uses 45
`a lead screw coupled to motors. The motors can be of the
`DC, stepper or solenoid varieties. These drive systems
`provide an axial displacement of the syringe or reservoir
`piston thereby dispensing the medication to the user. Pow(cid:173)
`ered drive systems are advantageous since they can be 50
`electronically controlled to deliver a predetermined amount
`of medication by means well known in the art.
`In the operation of these pump systems, the reservoir
`piston will be fully advanced when vitually all of the fluid
`in the reservoir has been dispensed. Correspondingly, the 55
`axial displacement of the motor lead screw is also typically
`fully displaced. In order to insert a new reservoir which is
`full of fluid, it is necessary to restore the lead screw to its
`original position. Thus the lead screw will have to be
`rewound or reset.
`DC motors and stepper motors are advantageous over
`solenoid motors in that the former arc typically easier to
`operate at speeds that allow rewinding the drive system
`electronically. Solenoid based drive systems, on the other
`hand, often must be reset manually, which in turn makes 65
`water resistant construction of the pump housing more
`difficult.
`
`25
`
`10
`
`2
`Lead screw drive systems commonly use several gears
`which are external to the motor. FIG. 1 shows such a lead
`screw arrangement which is known in the art. A motor 101
`drives a lead screw 102 which has threads which are
`5 engaged with a drive nut 103. Thus the rotational force of the
`lead screw 102 is transferred to the drive nut 103 which
`causes it to move in an axial direction d. Because the drive
`nut 103 is fixably attached to a reservoir piston 104, it
`likewise will be forced in an axial direction d', parallel to
`direction d, thus dispensing the fluid from the reservoir 105
`into the infusion set 106. The entire assembly can be
`contained in a water resistant housing 107.
`FIG. 2 shows a different lead screw arrangement which
`also is known in the art. In this arrangement, a motor 201 ( or
`a motor with an attached gear box) has a drive shaft 201a
`15 which drives a set of gears 202. The torque is then trans(cid:173)
`ferred from the gears 202 to a lead screw 203. The threads
`of the lead screw 203 are engaged with threads [ not shown]
`in a plunger slide 204. Thus the torque of the lead screw 203
`is transferred to the slide 204 which causes it to move in an
`20 axial direction d', parallel to the drive shaft 201a of the
`motor 201. The slide 204 is in contact with a reservoir piston
`205 which likewise will be forced to travel in the axial
`direction d' thus dispensing fluid from the reservoir 206 into
`the infusion set 207. The assembly can be contained in a
`water resistant housing 208.
`As previously noted, these lead screw drive systems use
`gears which are external to the motor. The gears are in
`combination with a lead screw with external threads which
`is used to drive lhe reservoir's piston. This external arrange(cid:173)
`ment occupies a substantial volume which can increase the
`overall size of the pump. Moreover, as the number of drive
`components, such as gears and lead screw, increases, the
`torque required to overcome inherent mechanical inefficien(cid:173)
`cies can also increase. As a result, a motor having sufficient
`torque also often has a consequent demand for increased
`electrical power.
`Yet another known drive is depicted in FIGS. 3a and 3b.
`A reservoir 301 fits into the unit's housing 302. Also shown
`are the piston member 303 which is comprised of an
`elongated member with a substantially circular piston head
`304 for displacing the fluid in the reservoir 301 when driven
`by the rotating drive screw 305 on the shaft (not visible) of
`the drive motor 306.
`As is more clearly shown in FIG. 3b, the reservoir 301,
`piston head 304 and piston member 303 comprise an inte(cid:173)
`grated unit which is placed into the housing 302 (FIG. 3a).
`The circular piston head 304 displaces fluid in the reser(cid:173)
`voir upon axial motion of the piston member 303. The
`rearward portion of the piston member 303 is shaped like a
`longitudinal segment of a cylinder as shown in FIG. 3b and
`is internally threaded so that it may be inserted into a
`position of engagement with the drive screw 305. The drive
`screw 305 is a threaded screw gear of a diameter to mesh
`with the internal threads of the piston member 303. Thus the
`motor 306 rotates the drive screw 305 which engages the
`threads of the piston member 303 to displace the piston head
`304 in an axial direction d.
`While the in-line drive system of FIG. 3a achieves a more
`60 compact physical pump size, there are problems associated
`with the design. The reservoir, piston head and threaded
`piston member constitute an integrated unit. Thus when the
`medication is depleted, the unit must be replaced. This
`results in a relatively expensive disposable item due to the
`number of components which go into its construction.
`Moreover the design of FIG. 3a is not water resistant.
`Because the reservoir, piston head and threaded piston
`
`Sanofi Exhibit 2171.016
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`3
`member are removable, the drive screw 305 and motor 306
`are exposed to the atmosphere. Any water which might come
`in contact with the drive screw 305 and motor 306 will result
`in corrosion and probable motor failure.
`The design of FIG. 3a further gives rise to problems
`associated with position detection of the piston head 304.
`The piston member 303 can be decoupled from the drive
`screw 305. However, when another reservoir assembly is
`inserted, it is not known by the system whether the piston
`head 304 is in the fully retracted position or in some 10
`intermediate position. Complications therefore are presented
`with respect to providing an ability to electronically detect
`the position of the piston head 304 in order to determine the
`extent to which the medication in reservoir 301 has been
`depleted.
`The construction of pumps to be water resistant give rise
`to operational problems. As the user travels from various
`elevations, such as might occur when traveling in an air
`plane, or as the user engages in other activities which expose
`the pump to changing atmospheric pressures, differential 20
`pressures can arise between the interior of the air tight/
`water-resistant pump housing and the atmosphere. Should
`the pressure in the housing exceed external atmospheric
`pressure, the resulting forces could cause the reservoir piston
`to be driven inward thus delivering unwanted medication.
`Thus it is desirable to have an improved, compact, water
`resistant drive system which permits safe user activity
`among various atmospheric pressures. Moreover it is desir(cid:173)
`able that such a system employ inexpensive medication
`reservmrs.
`
`15
`
`25
`
`30
`
`US 6,248,093 Bl
`
`4
`In yet another embodiment , the pump includes a key
`which is coupled with the plunger slide and which is
`operable to permit movement of the plunger slide in the
`direction of the at least two positions but prevent movement
`5 of the plunger slide in any other direction.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a side plan view of a conventional lead-screw
`drive mechanism.
`FIG. 2 is a side plan view of a another conventional
`lead-screw drive mechanism.
`FIG. 3a is a perspective view of another conventional
`lead-screw drive mechanism.
`FIG. 3b shows the details of a disposable reservoir with
`the piston and drive member withdrawn of the lead-screw
`drive mechanism of FIG. 3a.
`FIG. 4 is a side plan, cut-away view of a drive mechanism
`in a retracted position in accordance with an embodiment of
`the present invention.
`FIG. 5 is a perspective view of the in-line drive mecha(cid:173)
`nism of FIG. 4 outside of the housing.
`FIG. 6 is a cut-away perspective view of the drive
`mechanism of FIG. 4 in a retracted position.
`FIG. 7a is a side plan, cut-away view of the drive
`mechanism of FIG. 4 in an extended position.
`FIG. 7b is a cut-away perspective view of the drive
`mechanism of FIG. 4 in an extended position.
`FIG. 8 is a cut-away perspective view of an anti-rotation
`device for use with the drive mechanism shown in FIG. 4.
`FIG. 9 is a cross-sectional view of a segmented (or
`telescoping) lead screw in accordance with an embodiment
`of the present invention.
`FIGS. 10a, 10b and 10c are cross-sectional views of
`various embodiments of venting ports for use with the drive
`mechanism of FIG. 4.
`FIG. 11 is a partial, cross-sectional view of a reservoir and
`40 plunger slide assembly.
`FIG.12 is a partial, cross sectional view of a reservoir and
`a reservoir connector.
`FIGS. 13a and 13b are plunger slide force profile dia(cid:173)
`grams.
`
`45
`
`35
`
`SUMMARY OF THE PREFERRED
`EMBODIMENTS
`An improved pump is provided with a reservoir for
`accommodation of a liquid and a movable piston for varying
`the size of the reservoir and adapted to discharge the liquid
`from the reservoir through the outlet. In a certain aspect of
`the present inventions, a plunger slide is releasably coupled
`with the movable piston and has al least two positions. A
`driving device, such as a motor, is operably coupled to a
`drive member, such as a drive screw. The motor is disposed
`in-line with the drive screw and the plunger slide. The drive
`screw is operably connected to the plunger slide and is
`disposed to be substantially enclosed by the plunger slide
`when it is in at least one position. The drive screw is adapted
`to advance the plunger slide in response to operation of the
`motor.
`In one alternative, a housing for the reservoir, the movable
`piston, the plunger slide, the drive screw and the motor is
`provided along with a sealing device, such as an 0-ring, that 50
`separates the portion of the housing which encloses the
`movable piston from the portion of the housing which
`encloses the drive screw and the motor.
`In another preferred embodiment, a coupler is attached to
`the plunger slide. The coupler is removably attached to the 55
`movable piston to prevent separation of the movable piston
`from the plunger slide when the air pressure in the housing
`exceeds the pressure external to the water resistant housing.
`In still another embodiment, the housing includes a vent
`port between the exterior and interior of the housing. The 60
`vent port contains a hydrophobic material or a relief valve,
`either of which will permit air to pass through the vent, but
`will prevent waler from passing.
`In another alternative, the driving device is a motor which
`is attached to the housing with a compliance mount. In 65
`another embodiment, the plunger slide comprises a telescop(cid:173)
`ing lead screw formed from at least two segments.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`
`In the following description, reference is made to the
`accompanying drawings which form a part hereof and which
`illustrate several embodiments of the present inventions. It
`is understood that other embodiments may be utilized and
`strnctural and operational changes may be made without
`departing from the scope of the present inventions.
`As shown in the drawings for purposes of illustration,
`some aspects of the present inventions are directed to a drive
`mechanism for an infusion pump for medication or other
`fluids. In preferred embodiments, a releasable coupler
`couples an in-line drive to a plunger or piston of a reservoir
`to dispense fluids, such as medications, drugs, vitamins,
`vaccines, hormones, water or the like. However, it will be
`recognized that further embodiments of the invention may
`be used in other devices that require compact and accurate
`drive mechanisms.
`In addition, other embodiments use a telescoping drive
`member (or lead screw) to minimize the packaging dimen(cid:173)
`sions of the drive mechanism and the overall configuration
`
`Sanofi Exhibit 2171.017
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`US 6,248,093 Bl
`
`5
`of the medication pump. Still further, a ventilation feature
`using hydrophobic materials or a relief valve can be
`employed to equalized any pressure differentials which
`might otherwise exist between the atmosphere and the
`interior of the pump housing. As a back up to this ventilation
`feature, a threaded attachment permits a secure coupling
`between the reservoir piston and the in-line drive.
`FIG. 4 shows a side plan, cut-away view of an infusion
`pump drive mechanism according to a preferred embodi(cid:173)
`ment of the inventions, in which a housing 401, containing
`a lower section 402 for a power supply 420 and electronic
`control circuitry 422, accommodates a driving device, such
`as a motor 403 (e.g., a solenoid, stepper or d.c. motor), a first
`drive member, such as an externally threaded drive gear or
`screw 404, a second drive member, such as an internally
`threaded plunger gear or slide 405, and a removable vial or
`reservoir 406. The reservoir 406 includes a plunger or piston
`407 with O-rings or integral raised ridges for forming a
`water and air tight seal. The reservoir 406 is secured into the
`housing 401 with a connector 431 which also serves as the 20
`interface between the reservoir 406 and the infusion set
`tubing (not shown). In a preferred embodiment, the reservoir
`piston 407 is coupled to the plunger slide 405 by a releasable
`coupler. In the illustratec.1 emboc.limenl, the coupler incluc.les
`a female portion 424 which receives a male portion 426 25
`carried by the plunger slide 405. The female portion 424 is
`positioned at the end face 428 of the piston 407 and includes
`a threaded cavity which engages the threads of a male screw
`extending from the end 430 of the plunger slide 405.
`While preferred embodiments of the present inventions
`are directed to disposable, pre-filled reservoirs, alternative
`embodiments may use refillable cartridges, syringes or the
`like. The cartridge can be pre-filled with insulin ( or other
`drug or fluid) and inserted into the pump. Alternatively, the
`cartridge could be filled by the user using an adapter handle 35
`on the syringe-piston. After being filled, the handle is
`removed (such as by unscrewing the handle) so that the
`cartridge can be placed into the pump.
`Referring again to FIG. 4, as the drive shaft 432 of the 40
`motor 403 rotates, the drive screw 404 drives the plunger
`slide 405 directly to obtain the axial displacement against
`the reservoir piston 407 to deliver the predetermined amount
`of medication or liquid. When using a DC or stepper motor,
`the motor can be rapidly rewound when the reservoir is
`emptied or as programmed by the user. A sealing device,
`such as an O-ring seal 409 is in contact with the plunger slide
`405 thus allowing it to move axially while maintaining a
`water resistant barrier between the cavity holding the res(cid:173)
`ervoir 406 and the motor 403. This prevents fluids and other 50
`contaminants from entering the drive system.
`An anti-rotation key 410 is affixed to the plunger slide 405
`and is sized to fit within a groove (not shown) axially
`c.lisposec.1 in the housing 401. This arrangement serves to
`prevent motor and plunger slide rotation which might oth- 55
`erwise result from the torque generated by the motor 403 in
`the event that the friction of the O-ring seal 409 is not
`sufficient alone to prevent rotation.
`The motor 403 is a conventional motor, such as a DC or
`stepper motor, and is journal mounted in the housing 401 by
`a system compliance mounting 412. A system compliance
`mount can be useful in aiding motor startup. Certain types
`of motors, such as stepper motors, may require a great deal
`of torque to initiate rotor motion when the rotor's initial
`at-rest position is in certain orientations with respect to the
`motor's housing. A motor which is rigidly mounted may not
`have enough power to develop the necessary starting torque.
`
`6
`Including system compliance mounting permits the motor
`housing to turn slightly in response to high motor torque.
`This alters the orientation between the rotor and the housing
`such that less torque is required to initiate rotor motion. A
`5 compliance mount can include a rubberized mounting
`bracket. Alternatively, the mounting could be accomplished
`using a shaft bearing and leaf spring or other known com(cid:173)
`pliance mountings.
`FIG. 5 shows a perspective view of the in-line drive
`10 mechanism of FIG. 4 outside of the housing. The plunger
`slide 405 (internal threads not shown) is cylindrically shaped
`and has the screw-shaped male portion 426 of the coupler
`attached to one end thereof. The anti-rotation key 410 is
`affixed to the opposite end of the slide 405. The drive screw
`15 404 is of such a diameter as to fit within and engage the
`internal threads of the plunger slide 405 as shown in FIG. 4.
`A conventional gear box 501 couples the drive screw 404 to
`the drive shaft 432 of the motor 403.
`FIGS. 4 and 6 show the infusion pump assembly with the
`plunger slic.le 405 in !ht: rt:lrackc.l position. Tht: rt:st:rvoir 406
`which may be full of medication or other fluid is inserted in
`a reservoir cavity 601 which is sized to receive a reservoir
`or vial. In the retracted position, the plunger slide 405
`encloses the gear box 501 (not visible in FIG. 6) while the
`drive screw 404 (not visible in FIG. 6) remains enclosed
`within the plunger slide 405 but is situated close to the
`coupler.
`The motor 403 may optionally include an encoder (not
`shown) which in conjunction with the system electronics can
`monitor the number of motor rotations. This in turn can be
`used to accurately determine the position of the plunger slide
`405 thus provic.ling information relating lo !ht: amount of
`fluid dispensed from the reservoir 406.
`FIGS. 7a and 7b show the infusion pump assembly with
`the plunger slide 405 in the fully extended position. In this
`position, the plunger slide 405 has withdrawn from over the
`gear box 501 and advanced into the reservoir 406 behind the
`reservoir piston 407. Accordingly, the plunger slide 405 is
`sized to fit within the housing of the reservoir 406, such that
`when the reservoir piston 407 and the plunger slide 405 are
`in the fully extended position as shown, the reservoir piston
`407 has forced most, if not all, of the liquid out of the
`reservoir 406. As explained in greater detail below, once the
`reservoir piston 407 has reachec.1 the enc.1 of its travel path
`indicating that the reservoir has been depleted, the reservoir
`406 may be removed by twisting such that the threaded
`reservoir piston 407 (not shown in FIG. 7b) disengages from
`the male portion 426 of the coupler.
`In a preferred embodiment, the motor drive shaft 432,
`gear box 501, drive screw 404, and plunger slide 405 are all
`coaxially centered within the axis of travel 440 (FIG. 4) of
`the reservoir piston 407. In certain of the alternative
`embodiments, one or more of these components may be
`offset from the center of the axis of travel 440 and yet remain
`aligned with the axis of travel which has a length which
`extenc.ls the length of the reservoir 406.
`FIG. 8 is a cut away perspective view of an anti-rotation
`device. The anti-rotation key 410 consists of a ring or collar
`60 442 with two rectangular tabs 436 which are spaced 180°
`apart. Only one tab is visible in FIG. 8. The ring portion 442
`of the key 410 surrounds and is attached to the end of the
`plunger slide 405 which is closest to the motor. Disposed in
`the housing 401 are two anti-rotation slots 434, only one of
`65 which is visible in FIG. 8. The anti-rotation slots 434 are
`sized to accept the rectangular tabs of the key 410. As the
`plunger slide 405 moves axially in response to the motor
`
`30
`
`45
`
`Sanofi Exhibit 2171.018
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`US 6,248,093 Bl
`
`7
`torque as previously described, the slots 434 will permit the
`key 410 to likewise move axially. However the slots 434 and
`the tabs 436 of the key 410 will prevent any twisting of the
`plunger slide 405 which might otherwise result from the
`torque generated by the motor.
`FIG. 9 illustrates a split lead-screw ( or plunger slide)
`design in accordance with an embodiment of the present
`inventions. The use of a split lead-screw or telescoping lead
`screw allows the use of an even smaller housing for the drive
`mechanism. A telescoping lead-screw formed from multiple 10
`segments allows the pump to minimize the dimensions of
`the drive mechanism, in either in-line or gear driven drive
`mechanisms.
`In preferred embodiments, an interior shaft 901 is rotated
`by a gear 906 which is coupled to a drive motor (not shown).
`This in turn extends a middle drive segment 902 by engaging
`with the threads of an internal segment 904. The middle
`segment 902 carries an outer segment 903 forward with it in
`direction d as it is extended to deliver fluid. When the middle
`stgmtnl 902 is fully txltnc.lec.l, !ht inttrnal stgmtnt 904
`engages with a stop 905 on the middle segment 902 and
`locks it down from pressure with the threads between the
`middle and internal segments. TI1e locked middle segment
`902 then rotates relative to the outer segment 903 and the
`threads between the middle segment 902 and the outer 25
`segment 903 engage to extend the outer segment 903 in
`direction d to its full length.
`The use of multiple segments is not limited to two or three
`segments; more may be used. The use of three segments
`reduces the length of the retracted lead-screw portion of the
`drive mechanism by half. In alternative embodiments, the
`outtr stgmtnl may be rnnnecttc.l lo the motor anc.l the inntr
`segment may be the floating segment. In preferred
`embodiments, O-rings 907 are used to seal each segment
`relative to the other and to form a seal with the housing to
`maintain water sealing and integrity.
`As previously noted, the construction of these pumps to
`be water resistant can give rise to operational problems. As
`the user engages in activities which expose the pump to
`varying atmospheric pressures, differential pressures can
`arise between the interior of the air tight/water-resistant
`housing and the atmosphere. Should the pressure in the
`housing exceed external atmospheric pressure, the resulting
`forces conic.I cause the reservoir piston to be driven inw arc.I
`thus delivering unwanted medication. On the other hand,
`should the external atmospheric pressure exceed the pres(cid:173)
`sure in the housing, then the pump motor will have to work
`harder to advance the reservoir piston.
`To address this problem, a preferred embodiment of the
`inventions includes a venting port which resists the intrusion
`of moisture. Referring to FIG. 7b, venting is accomplished
`through the housing 401 into the reservoir cavity 601 via a
`vent port 605. The vent port can be enclosed by a relief valve
`(not shown) or covered with hydrophobic material. Hydro(cid:173)
`phobic material permits air to pass through the material
`while resisting the passage of water or other liquic.ls from
`doing so, thus permitting water resistant venting. The pre(cid:173)
`ferred embodiment uses a hydrophobic material such as
`Gore-Tex®, PTFE, HDPE, UHMW polymers from sources
`such as W.I. Gore & Associates, Flagstaff, Az., Porex
`Technologies, Fairburn, Ga., or De WAL Industries,
`Saunderstown, R.I.. It is appreciated that other hydrophobic
`materials may be used as well.
`These materials are available in sheet form or molded 65
`(press and sintered) in a geometry of choice. Referring to
`FIGS. lOa-lOc, preferred methods to attach this material to
`
`8
`the housing 401 include molding the hydrophobic material
`into a sphere 1001 (FIG. 10a) or a cylinder 1002 (FIG. 10b)
`and pressing it into a cavity in the pre-molded plastic
`housing. Alternatively, a label 1003 (FIG. 10c) of this
`5 material could be made with either a transfer adhesive or
`heat bond material 1004 so that the label could be applied
`over the vent port 605. Alternatively, the label could be
`sonically welded to the housing. In either method, air will be
`able to pass freely, but water will not.
`In an alternative embodiment (not shown), the vent port
`could be placed in the connector 431 which secures the
`reservoir 406 to the housing 401 and which also serves to
`secure and connect the reservoir 406 to the infusion set
`tubing (not shown). As described in greater detail in copend-
`15 ing application Ser. No. 09/428,818 filed contemporane(cid:173)
`ously herewith (Attorney docket No. 0059-0307), which
`application is incorporated by reference in its entirety, the
`connector and infusion set refers to the tubing and apparatus
`which connects the outlet of the reservoir to the user of a
`20 medication infusion pump.
`An advantage of placing the vent port and hydrophobic
`