United States Patent c191
`Kamen
`
`[I IJ Patent Number:
`[45] Date of Patent:
`
`4,648,872
`Mar. 10, 1987
`
`[76]
`
`[56]
`
`[54] VOLUMETRIC PUMP WITH REPLACEABLE
`RESERVOIR ASSEMBLY
`Inventor: Dean L. Kamen, 46 Gage Rd.,
`Bedford, N.H. 03102
`[21] Appl. No.: 551,851
`[22] Filed:
`Nov. 15, 1983
`Int. Cl,4 ............................................. A61M 37/00
`[51]
`[52] U.S. Cl . .................................... 604/155; 604/211;
`604/224; 604/228; 604/245; 128/DIG. 12;
`222/390
`[58] Field of Search ................... 604/155, 65, 67, 118,
`604/151, 152,154,208,211,213,218,224,228,
`230, 245, 110; 128/DIG. 12; 222/390
`References Cited
`U.S. PATENT DOCUMENTS
`996,128 6/1911 Payne et al ..
`2,602,446 8/1952 Glass et al ........................... 128/218
`2,627,270 2/1953 Glass ................................... 604/155
`2,627,999 2/1953 Swan ................................... 222/390
`2,725,877 12/1955 Reiter et al ......................... 604/224
`2,734,504 2/1956 Crescas et al ....................... 604/155
`3,155,090 11/1964 Holter ..................................... 128/2
`3,156,236 11/1964 Williamson ........................ 128/2.05
`3,395,704 8/1960 Frey et al ............................ 604/154
`3,456,649 7/1969 Jewett ·················"·····•oo••···· 128/214
`3,623,474 11/1971 Hellman et al ..................... 128/2 R
`3,631,847 1/1972 Hobbs ................................. 128/2 R
`3,701,345 10/1972 Hellman et al. .................... 128/2 R
`3,771,694 11/1973 Kaminski .................... 128/DIG. 13
`3,790,048 2/1974 Luciano et al ...................... 604/211
`3,811,442 5/1974 Maroth ........................... 128/218 R
`3,812,843 5/1974 Wootten et al ..................... 128/2 R
`3,858,581 1/1975 Kamen ............................ 128/218 A
`3,880,138 4/1975 Wootten et al. ................... 128/2 A
`3,886,938 6/1975 Szabo et al. .................... 128/218 A
`4,059,110 11/1977 Wuthrich et al ............... 128/218 A
`4,073,321 2/1978 Moskowitz .......................... 604/208
`
`4,108,177 8/1978 Pistor .................................. 604/155
`4,126,132 11/1978 Portner et al. .................. 128/214 F
`4,142,524 3/1979 Jassawalla et al .............. 128/214 F
`4,150,672 4/1979 Whitney et al ................. 128/214 F
`4,191,187 3/1980 Wright ............................ 128/218 A
`4,258,866 3/1981 Bergman ............................. 222/390
`4,269,185 5/1981 Whitney et al. ................ 128/214 F
`4,300,554 11/1981 Hessberg et al. ............... 128/218 A
`4,320,757 3/1982 Whitney et al. ................ 128/214"F
`4,326,517 4/1982 Whitney et al. ................ 128/214 F
`4,342,311 8/1982 Whitney et al ................. 128/214 F
`4,367,738 1/1983 Legendre et al. ................... 604/110
`4,391,272 7/1983 Staempfli ............................ 604/110
`4,399,712 8/1983 Oshikubo et al. ................... 604/155
`4,465,475 8/1984 Madorf et al ....................... 604/155
`4,493,704 1/1985 Beard et al .......................... 604/154
`
`Primary Examiner-Stephen C. Pellegrino
`Assistant Examiner-Mark Rooney
`Attorney, Agent, or Firm-Bromberg, Sunstein &
`McGregor
`
`ABSTRACT
`[57]
`An infusion pump has a removable reservoir including a
`piston and drive member. The drive member is an inter(cid:173)
`nally threaded elongated portion of the piston. A motor
`rotates a short drive screw, which engages the threads
`of the drive member to displace the piston in the reser(cid:173)
`voir. In one embodiment the piston is attached to the
`drive member by a severable central stem which breaks
`away to allow engagement with the drive screw. With
`the stem severed, the piston cannot be retracted, or the
`reservoir refilled. Other safety features are shown for
`locking the displaced piston in the reservoir. A digital
`metering system has a safety circuit to prevenf danger(cid:173)
`ous failure modes of the rotation sensor and motor drive
`systems.
`
`7 Claims, 17 Drawing Figures
`
`Sanofi Exhibit 2169.001
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent Mar. 10, 1987
`
`Sheet 1 of 6
`
`4,648,872
`
`/6
`
`FIG. IA
`
`Sanofi Exhibit 2169.002
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent Mar. IO, 1987
`
`Sheet2 of6
`
`FIG. JD
`
`FIG.2
`
`23
`
`FIG.2A
`
`II
`
`FIG. 2B
`
`Sanofi Exhibit 2169.003
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent Mar. IO, 1987
`
`Sheet3 of6
`
`4,648,872
`
`FIG. 2C
`
`35
`
`/4
`
`3/
`
`FIG. 3
`
`FIG. 3A
`
`II
`
`/3
`
`/3
`
`FIG. 3B
`
`Sanofi Exhibit 2169.004
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent Mar. IO, 1987
`
`Sheet 4 of 6
`
`4,648,872
`
`FIG. 4
`
`FIG. 5A
`
`13
`
`12 FIG. 5B
`
`FIG. 5C
`
`Sanofi Exhibit 2169.005
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent Mar.10, 1987
`t-"-77
`
`Sheet5 of6
`
`4,648,872
`
`I
`
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`
`FIG.8
`
`Sanofi Exhibit 2169.006
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`U.S. Patent Mar. 10, 1987
`
`Sheet6 of6
`
`4,648,872
`
`16
`
`7
`
`FIG. 9
`
`Sanofi Exhibit 2169.007
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`1
`
`4,648,872
`
`VOLUMETRIC PUMP WITH REPLACEABLE
`RESERVOIR ASSEMBLY
`
`TECHNICAL FIELD
`This invention relates to medical infusion pumps and
`more particularly pumps capable of home use by ambu(cid:173)
`latory patients and pumps having built in controls for
`sustained or periodic infusions over a substantial time.
`
`2
`BRIEF DESCRIPTION OF THE INVENTION
`The present invention overcomes the foregoing liini(cid:173)
`tations by providing a simplified mechanical structure
`5 for a pump including a reservoir, piston and drive mem(cid:173)
`ber, in which the drive member may be internally
`threaded for a substantial length. A relatively short
`drive screw, which may be motor driven, engages the
`drive member to propel the piston in the reservoir. By
`10 using a piston drive member in which the skirt is omit(cid:173)
`ted on one side, it is possible to place the motor and
`drive screw substantially within the extended piston
`member body, realizing a substantial reduction in space
`requirements. Additionally, such a structure requires no
`drive member journals, and dispenses with the cumber(cid:173)
`some rack or leadscrew characteristic of prior art de(cid:173)
`vices. There may result a pump structure with miniinal
`mass, miniinal frictional losses or mechanical ineffi-
`ciency, and no mechanical backlash. In a preferred
`embodiment the reservoir, piston, and drive member
`may be an assembly that can be removed from the
`pump. In one preferred embodiinent, interlocking de(cid:173)
`tents on the piston and reservoir walls may be used to
`prevent withdrawal or reuse of the reservoir assembly
`or components after use. In another preferred embodi(cid:173)
`ment, a shearable stem, which may be integrally formed
`with the piston face, holds the piston and drive member
`together for setting up or bleeding the pump. The stem
`then is sheared off by twisting so that the piston face
`floats free, preventing re-use of the reservoir assembly.
`The invention is well adapted for use with battery pow(cid:173)
`ered drive, and microprocessor chip control program(cid:173)
`ming means, for dependable use with small power re(cid:173)
`quirements in hospital bedside or ambulatory outpatient
`settings. These and other features of the inven~on will
`become apparent by reference to the drawings.
`
`BACKGROUND ART
`Much interest has arisen in recent years in the devel(cid:173)
`opment of medical infusion pumps capable of relatively
`continuous operation and also in the development of 15
`infusion pumps having the ability to administer pre(cid:173)
`cisely controlled volumes of fluid at preselected inter(cid:173)
`vals. Unlike the case with a parenteral fluid administra(cid:173)
`tion apparatus, which typically operates by gravity
`flow from a relatively large reservoir of fluid, medica- 20
`tion infusion generally involves administration of small
`dosages so as to achieve a prescribed optimum level of
`medication in the bloodstream of the patient. Due to
`differences in the rates of metabolism of, or elimination
`of, various medicines, the attainment of precise blood- 25
`stream medication levels is usually achieved by the
`periodic administration of a dosage of medication,
`where determination of the precise dosage and the cor(cid:173)
`rect interval between doses will depend on the particu- 30
`Jar medication involved as well as criteria peculiar to
`the patient. Such repeated administration of medicines
`can be difficult to achieve because of erratic communi(cid:173)
`cations with, or supervening demands, on hospital nurs(cid:173)
`ing staff; moreover repeatedly giving a patient injec- 35
`tions can be traumatic. Thus emphasis has grown on
`developing versatile medical infusion pumps to auto(cid:173)
`matically administer a sustained sequence or rate of
`infusions. Pumps of several types are known in the prior
`art. One species of pump involves rather massive me- 40
`chanical elements for the pump and dosage setting de(cid:173)
`vice so as to give the very precisely controlled sequence
`of high pressure infusions necessary for radiography.
`Such devices are disclosed in U.S. Pat. Nos. 3,701,345
`and 3,812,843, among others.
`Another, general purpose, species of pump utilizes a
`motor or clock drive to power a pushing mechanism,
`using a leadscrew or rack, for moving a plunger ar(cid:173)
`rangement. Examples of such devices are my medica(cid:173)
`tion injection device disclosed in U.S. Pat. No. SO
`3,858,581, or that of U.S. Pat. No. 4,059,110. Such de(cid:173)
`vices are more compact and are reasonably well
`adapted for use as bedside periodic infusion devices in a
`hospital setting. However these devices tend to be
`somewhat bulky and, for this reason, are less than opti(cid:173)
`mal for use on an ambulatory patient. Each of the prior
`art devices also suffers from a looseness in its mechani(cid:173)
`cal drive components which requires close attention
`when setting up the initial pumping operation to ensure 60
`that the device actually pumps a full dose during the
`first duty cycle of its activation. Additionally each of
`the prior art devices has a rather complex mechanical
`structure, introducing significant inertial and frictional
`factors affecting the ease and cost of maintaining the 65
`units in reliable operating condition over extended
`times, and making them unsuitable for battery powered
`operation.
`
`45
`
`55
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIG. IA shows a perspective view of a programma(cid:173)
`ble microprocessor-controlled embodiinent of the in(cid:173)
`vention.
`FIG. 1B shows a perspective view of an embodiinent
`siinilar to that of FIG. IA.
`FIG. 2 shows details of a disposable reservoir, in
`accordance with the present invention, with the piston
`and drive member withdrawn.
`FIGS. 2A, 2B and 2C show various embodiinents of
`a reservoir safety retaining feature utilizing a lip, barb,
`or groove.
`FIG. 3 shows a side view of the piston and drive
`member, showing the placement of the motor and
`drivescrew within its contours.
`FIG. 3A shows a cross-sectional view of the piston
`member and safety barb.
`FIG. 3B shows a cross-sectional view of the piston
`member and the breakaway safety stem.
`FIG. 4 shows a perspective view of the piston mem(cid:173)
`ber, skirt profile and drive engagement threads.
`FIGS .. SA, SB and SC show different embodiinents of
`the piston face adapted to provide a fluid seal.
`FIG. 6 shows a large volume embodiinent adapted
`for sustained bedside infusion.
`FIG. 7 shows a section along line 7-7 of FIG. 6,
`showing the motor and drive.
`FIG. 8 shows the embodiinent of FIG. 6 having the
`retaining slide cover.
`
`Sanofi Exhibit 2169.008
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`3
`FIG. 9 shows the large volume pump of FIG. 6 in(cid:173)
`cluding the housing adapted to house a keyboard, con(cid:173)
`trol circuitry and power supply.
`
`DETAILED DESCRIPTION OF THE
`INVENTION
`FIG. IA shows a perspective view of a complete
`infusion pump according the present invention, in
`which a housing 16, containing a power supply and
`microprocessor control circuity, accomodates a motor- 10
`ized drive unit and a disposable piston/reservoir assem(cid:173)
`bly in its upper portion. A keyboard 7, preferably of an
`impermeable, e.g. membrane-type, construction is used
`to enter program information to set a schedule of
`amounts and timing of medication doses. A display 9 is 15
`used to display the instrument mode, to give instruc(cid:173)
`tions for data entry, and to signal certain operator cor(cid:173)
`rectable steps and alarm states. In the upper portion of
`the housing is mounted a reservoir 11 with a centrally
`disposed elongated piston member 12. The reservoir 11 20
`is secured at one end by a gentle snap fit within oppos(cid:173)
`ing portions of a yoke 15 formed by the housing body.
`(A single side of yoke 15 is shown in this figure.) At the
`other end of the reservoir is an axially-sliding cover
`portion 10 of the housing which overlies the end of the 25
`reservoir 11 and bears against the longitudinal portion
`of piston member 12 to align it. To minimize friction
`against the piston member 12 as it slides within the
`reservoir 11, there is provided a protuding longitudinal
`ridge 122 comprising the area of contact between the 30
`piston member and the reservoir 11 and sliding cover
`10.
`FIG. 1B shows a perspective view of a complete
`infusion unit similar to the embodiment of FIG. IA and
`viewed from the opposite side. A reservoir 11, which 35
`may be graduated along its surface, fits into a recess 17
`in the unit's housing 16 and is retained by the yoke 15
`which varies only slightly from the yoke shown in FIG.
`IA. The reservoir 11 is substantially in the form of a
`hollow cylinder, and yoke 15 is positioned so as to re- 40
`tain the reservoir in axial alignment. It has been found
`that the use of the split yoke 15 permits convenient
`insertion of the reservoir 11 into recess 17. This yoke is
`located to position the outlet nipple, shown at 29 in
`FIG. 2, leaving space for the attachment ofa connector 45
`181 and infusion tube 18, both of which are of a conven(cid:173)
`tional design. Also shown in FIG. 1B are the piston
`member 12, an elongated member with a substantially
`circular head 13 for hermetically displacing the fluid in
`the reservoir 11 when driven by the rotating screw 50
`drive 14 on the shaft of the drive motor (not visible). As
`shown, the housing 16 removably holds the reservoir 11
`and piston member 12 as a unit. The circular piston head
`13 displaces fluid in the reservoir upon axial motion of
`the piston member. The rearward portion of the piston 55
`member is shaped like a longitudinal segment of cylin(cid:173)
`der as shown and is preferably internally threaded so
`that it may be inserted into a position of engagement
`with dnve screw 14. Drive screw 14 is a finely threaded
`screw gear, of a diameter to mesh with the internal 60
`threads of the piston member 12.
`In the embodiment shown, all of the mechanical ele(cid:173)
`ments of the pump and drive are housed in the top
`portion of the housing 16 and the remainder of housing
`16 serves to hold a battery or rechargeable power pack 65
`and a microprocessor control and rate selection means
`for the device. A cover 10, shown in phantom, slides in
`the direction of axis 8 so as to hold the piston member 12
`
`4,648,872
`
`4
`in engagement with the drive screw after the reservoir
`assembly is inserted in the housing. Alternatively, the
`cover 10 may be an integral fixed part of the housing 16,
`and provided with a slot on the side thereof and longitu-
`5 dinally disposed along axis 8; the slot would be suffi(cid:173)
`cient in size to permit insertion of the piston member 12
`when the piston-reservoir assembly is first loaded into
`the motor assembly. After the insertion of the piston
`member 12 into the slot, the piston member 12 is rotated
`about axis 8 until the member 12 assumes operating
`position underneath the cover, where the member 12
`may be retained by one or more nubs protruding toward
`axis 8 from the inside of the cover near the slot. In this
`manner the cover holds the piston in engagement with
`the drive screw.
`FIG. 2 shows the reservoir 11, with its outlet nipple
`29. The outlet nipple may be of any conventional shape
`such as a taper or bayonet lock, for attachment of a
`sterile connector fitting 181 and infusion tube 18. When
`used to center the reservoir with respect to a retaining
`stop as shown at 15 in FIG. 1B the nipple must be of
`sufficient length so that the stop 15 does not interfere
`with attachment of the connector fitting.
`At the other end of the reservoir is the rear edge 20 of
`the circular opening constituting the end of the reser(cid:173)
`voir chamber. The present device is intended for use in
`administering infusions over extended periods of time
`thus entailing some likelihood of contamination, or
`incubation of bacterial contaminants. For this reason, it
`is necessary to guard against misuse, particularly the
`possibility that reservoir units may be removed and
`refilled with medication. Such refilling is poor medical
`practice, and would pose a substantial risk of introduc(cid:173)
`ing pyrogenic, infectious or otherwise toxic contami(cid:173)
`nants into the infusion fluid.
`Accordingly in one preferred embodiment of this
`invention, a safety feature has been incorporated to
`prevent withdrawal of the piston and refilling of the
`reservoir. This safety feature includes a modification to
`the inner surface contour of the reservoir adjacent to
`the rear edge 20 of the reservoir, together with a mating
`modification to the distal end of the piston member.
`Such modifications to the reservoir assembly are shown
`in cross-section in FIGS. 2A, 2B, and 2C, and may
`include a lip 21, a barb 22, or a groove 24 located to
`engage the piston member and prevent its withdrawal
`after use. The piston member has a corresponding barb
`32 shown in FIG. 3A projecting radially outward from
`its distal end which engages the mating portion of the
`reservoir wall for causing the piston to be locked into
`the reservoir upon full insertion. The piston member
`also has a rounded shoulder 33 preferably extending
`along each edge of the piston member, to prevent grip(cid:173)
`ping the member which could defeat the safety lock. It
`has been found that the lip 21 or barb 22 of the reservoir
`need not protrude more than a few thousandths of an
`inch above the interior face 23 of the reservoir chamber
`to be effective, and thus need introduce no unreasonable
`frictional drag upon the piston member. Frictional drag
`may be altogether eliminated by use of the groove 24
`and barb 32 embodiment of the safety interlock.
`A further preferred embodiment is shown in FIG. 3B.
`(FIGS. 3 and 3A are discussed below.) In the embodi(cid:173)
`ment of FIG. 3B, piston face 13 is attached to a safety
`stem 131, which may be integrally formed with face 13,
`extending through aperture 121 in piston member 12,
`and holding face 13 to member 12. Safety stem 131 is
`capable of transmitting force in either direction along its
`
`Sanofi Exhibit 2169.009
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`4,648,872
`
`5
`length, and accordingly to set up and bleed a reservoir
`it is only necessary to push or pull on stem 131 as for a
`conventional syringe. However, with stem 131 intact, it
`is not possible to place the reservoir into the housing 16
`or into engagement with the motor drive gear 14. Ac- 5
`cordingly, to mount the assembly for operation, the
`stem is twisted, breaking off at a narrowed stress point
`132, thus removing the obstacle to motor engagement.
`With the stem thus removed, the face 13 is no longer
`attached to the piston body 12. It will advance when 10
`driven by the piston member, but will remain within the
`reservoir and will not retract when member 12 is with(cid:173)
`drawn. Face 13 may contain a polygonal recess fitted
`over a corresponding polygonal protrusion of body 12
`to prevent face 13 from turning as the stem is twisted to 15
`break it away, thus facilitating the breaking away of the
`safety stem.
`FIG. 3A shows a longitudinal cross section of one
`embodiment of the piston member 12, in which 34 is a
`nub integrally formed with piston member 12 for retain- 20
`ing the front face 13. Internal screw threads 31 extend
`the length of the inside face of the piston member back
`from the front face, culminating in a rounded shoulder,
`33 visible at the distal edge. On the exterior face of the
`piston member 12 precisely at the distal end thereof is a 25
`slight protrusion 32 which engages the corresponding
`lip 21, barb 22 or groove 24 shown at FIGS. 2A, 2B, or
`2C when the piston has been fully displaced into the
`reservoir 11, thus preventing removal of the piston or
`refilling of the reservoir. In this regard the shoulder 33 30
`further discourages gripping of the piston, to safeguard
`against removal.
`Referring now to FIG. 3, there is shown in side view
`the piston member 12 including the front face 13, which
`is shown somewhat occluded by the surrounding reser- 35
`voir 11. Piston face 13 may be a soft neoprene or similar
`FDA-approved compound, such as is commonly used
`in the plunger of disposable syringes, which is titted
`over a ridged end or bulbous nub at the end of the piston
`member so as to be controllably moveable thereby. The 40
`. precise mode of attachment is well known in the art,
`·and accordingly no particular detail of that structure is
`shown. The portion of the piston member 12 which is
`immediately behind the soft front face 13 is substantially
`circular in cross-section, tapering to a long narrow 45
`body, which is shaped substantially like a segment of a
`cylinder of roughly constant thickness, threaded on the
`inside. The threads 31 are shown in cross-section. The
`precise shape of the long cylindrical segment is not
`critical so long as the exterior approximately conforms 50
`to the inner contour of the reservoir and the segment is
`not unduly wide or narrow. For the long portion of the
`piston member, a width of between 1/16- and 3/8 of an
`inch has been found to be practical, as it provides good
`engagement with the drive gear 14, has adequate rigid- 55
`ity and compressive strength to transmit the drive force,
`and is thin enough to avoid causing frictionally induced
`motion from the turning of the drive screw gear 14.
`Also shown in FIG. 3.is the screw gear 14 attached to
`the shaft of motor 35. As shown in FIG. 3 the motor has 60
`its principal cross-sectional dimension less than the di(cid:173)
`ameter of the screw gear, so that it fits entirely within
`the cylindrical region formed by rotating the piston
`member 12 about the common central axis of the reser(cid:173)
`voir/piston assembly. An electromagnetic motor hav- 65
`ing an integral high-ratio gear reduction unit coaxially
`mounted in a common housing between the motor and
`drive gear has been used. This allows the motor 35 to
`
`6
`drive the piston member 12 directly via the drive screw
`gear 14 without requiring other shafts, gears, pulleys,
`journals or other mechanical coupling or supporting
`elements in housing 16, resulting in a reduction of both
`inertial load and frictional losses as compared to con(cid:173)
`ventional pumps. The screw gear drive may be of any
`appropriate pitch with the choice of pitch dependent on
`the cross-sectional area of the reservoir, the desired
`delivery rates and infusion pressures, the available
`motor speed and torque output and the desired opera(cid:173)
`tional cycles.
`In constructing the screw drive, the thread profile of
`the screw gear in relation to the threads of the inner
`surface of the piston member is of some importance. In
`order to reduce backlash in the drive assembly, it is
`useful either to provide sharp peaks on the drive gear
`threads, so that the gear bites somewhat into the
`trenches of the threads of the piston member, or to
`provide a slight convexity or preloading in the face of
`the threads of either the drive gear or the piston mem(cid:173)
`ber.
`The operative metering principle involved in the
`control system of the present pump is that rotations of
`the drive screw 14 are directly proportional to the lin(cid:173)
`ear displacement of piston, hence to the volume of med(cid:173)
`icine delivered. The automatic control system for the
`present pump utilizes an internal light source which is
`reflected by a segmented optical disc connected to the
`drive train and detected by a photodetector so as to
`generate, in a manner known in the art, pulses represen(cid:173)
`tative of drive screw rotation. The control system oper(cid:173)
`ates the pump, starting at a predetermined time, and
`continuing until a predetermined number of pulses have
`been generated.
`Because the reservoir 11 holds sufficient medication
`for many hours or days of therapy, extreme precautions
`must be taken to assure that the pumps do not have
`faults which might result in a continuous pumping fail(cid:173)
`ure mode. This might occur for instance if the light
`source failed to turn on, or burned out, so that no re(cid:173)
`flected pulses signalled the continued operation of the
`pump. To prevent the occurrence of such dangerous
`events, a novel arrangement is used in the drive system
`of the pump. Specifically the light and drive motor are
`wired in series or otherwise arranged so that both nec(cid:173)
`essarily receive power if and only if the other is receiv(cid:173)
`ing and drawing power. In addition, condition sensing
`and power enabling circuitry are provided to further
`assure the device will shut down in the event a drive(cid:173)
`sensing component fails. In particular a second photo(cid:173)
`detector is provided to detect direct (as opposed to
`reflected) light from the internal light source; in the
`event that the second photodetector fails to detect light
`from the internal light source, the circuitry causes
`power to be removed from light-drive motor combina(cid:173)
`tion. With this approach the motor is powered and
`medicine is delivered to the patient only if the motor,
`the light, and the turn-counting mechanism are all func(cid:173)
`tioning. This circuit eliminates the dangers of unde(cid:173)
`tected motor jamming or lamp burnout. This peculiar
`arrangement of the operating components with the
`logic and condition sensors necessarily assures that
`none of the permutations of component failure can re(cid:173)
`sult in a dangerous operating condition, but merely in
`shut-down of the device.
`The foregoing discussion is not restricted to a rota(cid:173)
`tion sensing system using reflected light, and it would
`be obvious to one skilled in the art to construct a corre-
`
`Sanofi Exhibit 2169.010
`Mylan v. Sanofi
`IPR2018-01676
`
`

`

`4,648,872
`
`7
`sponding safety system for use in a rotation sensor em(cid:173)
`ploying a slotted disc and a transmitted beam of light.
`Accordingly the terms "reflected" or "reflecting" shall
`include "transmitted" or "transmitting" when used
`herein and in the claims. The precise details of the signal 5
`generation and detection also may be put into practice
`using a variety of components in a manner well known
`in the art.
`Turning now to FIG. 4, there is shown the piston
`member generally at 12 having internal threads 31 dis- 10
`posed along the length of the piston skirt, the portion of
`piston member 12 which extends laterally outward from
`piston head 13 and receives rotating screw gear 14. By
`engagement with the short rotating screw gear 14 the
`threads are operative to drive the piston a distance equal 15
`to the length of the threads 31. Because the piston skirt
`· must slide laterally into engagement with the drive
`screw, the skirt comprises not much more, and prefera(cid:173)
`bly less, than a semicircumferential portion of the cylin(cid:173)
`drical surface. In fact, since the piston skirt is used to 20
`transmit a linearly-directed drive force, shear forces are
`negligible; and because the piston head 13 is joined to
`the skirt portion along an arcuate edge, the skirt may
`safely be quite narrow.
`Such a drive member 12, having a narrow skirt, is 25
`shown in FIGS. SA, SB and SC, each of which shows an
`alternative embodiment of the piston face. In FIG. SA
`there is shown a piston member having a head 13 in
`which a circumferential groove holds a sealing ring 54.
`In FIG. SB a variation of the piston head with sealing 30
`ring 54 is shown, further having a flared cup 55. The
`flared cup provides a strong seal against fluid leakage in
`the direction opposing the flare. In FIG. SC is shown a
`piston member having an integrally-formed head with a
`frontal flared cup 55, are a spaced-apart rear portion 56, 35
`which, because of its thinness, may be of a large diame(cid:173)
`ter and operate as a bidirectional seal and scraper The
`piston skirt in any of these embodiments preferably has
`one or more longitudinal ridges, 122 in FIG. 2, arrayed
`along its exterior surface, to minimize the area of 40
`contact with the reservoir wall and to diminish fric(cid:173)
`tional drag.
`Turning now to FIG. 6, there is shown an embodi(cid:173)
`ment of the present invention usable as a large volume
`or macro-pump which may be suspended for bedside 45
`use in a vertical orientation in a manner similar to a
`conventional gravity infusion reservoir. The reservoir
`and drive assembly of the macro-pump are scaled-up
`versions of the device of FIG. 1, having a housing 66
`which accepts a reservoir 61 having a piston drive so
`member 62. The reservoir is removably attached to the
`housing as by lip 68 of the reservoir and circumferential
`groove 69 in the housing, or by a breech lock or similar
`arrangement. The piston member 62 includes a piston
`face 63, which may be further sealed using an O-ring or 55
`any of the structural variations shown in FIGS. SA, B
`or C.
`In FIG. 7 is shown a cutaway view along line 7-7 of
`the embodiment of FIG. 6, in which a motor 35 and
`drive screw 14 are shown driveably engaging internal 60
`threads of piston member 62. FIG. 8 further shows a
`slot in housing 66 for holding piston drive member 62 in
`alignment. After insertion of the reservoir assembly into
`the housing a sliding plate 80 may be moved along axis
`88 to close the slot and hold the piston drive member 62 65
`in engagement with screw gear 14. Alternate means for
`biasing the drive assembly are possible. Furthermore,
`while FIG. 7 shows a drive shaft journalled in the hous-
`
`8
`ing, such housing journals are not necessary, and the
`drive screw assembly may be simply mounted on the
`motor shaft, and the motor attached to the housing.
`Because of the rigidity of the reservoir and the pre(cid:173)
`cise volumetric relationship between drive rotations
`and piston displacement the macro-pump embodiment
`is readily adaptable to microprocessor drive control and
`information display in a manner to yield extremely pre(cid:173)
`cise dosage control. This rigid piston and reservoir
`configuration eliminates the air space characteristic of
`bottle reservoirs (which consequently require venting,
`drip chambers, and other equipment) and the undefined
`volume characteristic of bag reservoirs (which do not
`permit ready indication delivered fluid volume), achiev(cid:173)
`ing in a single apparatus the precision normally associ(cid:173)
`ated with separate, expensive, dosing pumps. The hous(cid:173)
`ing 66 may house both a microprocessor controller and
`a battery power supply.
`FIG. 9 shows such a device, in which the housing 16
`includes a keyboard 7 on one face, comprising a small
`number of programming keys. The panel may incorpo(cid:173)
`rate a display similar to 9 of FIG. 1, of a kind known in
`the art, on which may appear messages to guide an
`attendant in entering the program data related to reser(cid:173)
`voir volume, total dose and timing. Such a display may
`also display relevant information such as the total deliv(cid:173)
`ered dose, or time interval since last infusion, all of
`which may be conveniently coded, stored and retrieved
`starting with the basic operating pulse data of the pump
`drive and the coded program data of the microproces(cid:173)
`sor control, by techniques known in the art.
`It should be noted that although the foregoing discus(cid:173)
`sion speaks of the fabrication of one embodiment using
`a motor and reducing gear, it is by no means necessary
`that the motor be an electromagnetic rotary motor
`capable of continuous operation. Indeed, a stepping
`motor, or even a solenoid or piezo ratchet driven motor
`would be equally serviceable, as long as the device were