(19)
(11)EP 1 778 338 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
29.11.2017 Bulletin 2017/48

(21)Application number: 05762194.8

(22)Date of filing:  24.06.2005
(51)International Patent Classification (IPC): 
A61M 39/28(2006.01)
F16K 7/06(2006.01)
(86)International application number:
PCT/US2005/022453
(87)International publication number:
WO 2006/019519 (23.02.2006 Gazette  2006/08)

(54)

AUTOMATIC CLAMP APPARATUS FOR IV INFUSION SETS USED IN PUMP DEVICES

AUTOMATISCHES KLAMMERGERÄT FÜR IV-INFUSIONSSETS IN PUMPENVORRICHTUNGEN

APPAREIL PINCEUR AUTOMATIQUE POUR KITS DE PERFUSION IV UTILISES DANS DES DISPOSITIFS DE POMPAGE


(84)Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU MC NL PL PT RO SE SI SK TR

(30)Priority: 16.07.2004 US 892941

(43)Date of publication of application:
02.05.2007 Bulletin 2007/18

(73)Proprietor: CareFusion 303, Inc.
San Diego, CA 92130 (US)

(72)Inventors:
  • CLARKE, Christopher J.
    Burgess Hill, West Sussex, RH15 8BT (GB)
  • RUEDI, Rene
    Farnborough, Hampshire GU14 8PQ (GB)

(74)Representative: Richards, John et al
Ladas & Parry LLP
Temple Chambers 3-7 Temple Avenue London EC4Y 0DA
Temple Chambers 3-7 Temple Avenue London EC4Y 0DA (GB)


(56)References cited: : 
US-A- 4 398 542
US-A- 5 437 635
US-A1- 2002 165 503
US-A- 4 404 440
US-A- 5 967 484
US-B1- 6 364 279
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    FIELD OF INVENTION



    [0001] The invention is generally related to clamps used on flexible IV tubing in the field of intravenous (IV) infusion devices such as peristaltic pumps, and more particularly, to clamping devices used to prevent the free flow of fluids through an IV tube when the infusion pump is disengaged from the IV tube.

    BACKGROUND OF THE INVENTION



    [0002] It is a common practice to deliver fluids such as medications to a patient intravenously by means of a pumping device, such as a peristaltic pump. Such pumps are useful because they can deliver the medication in a highly controlled and precise fashion, and because they do so without coming in contact with the medication. The fluid is moved through a flexible IV tube by pressing a pumping member against the tube sufficiently to move the fluid in the tube downstream towards the patient. In the case of peristaltic mechanisms having multiple pumping fingers, the fingers are moved against the tube in a sequential manner from upstream to downstream to sequentially occlude the tube thereby moving the fluid in the tube downstream towards the patient. When the IV tube is mounted correctly in the pump, the IV tube is at all times occluded by one of the pumping members, thereby preventing the "free flow" of fluid to the patient. "Free flow" of medical fluids is undesirable since the flow of the fluid is uncontrolled and the prescribed treatment is not followed.

    [0003] It is common for the peristaltic pumping mechanism to be located in a housing with a hinged door. The tube through which the fluid is to be moved is placed in contact with the pumping mechanism inside the door, with the ends of the tubing typically extending out the top and bottom of the door opening. As the door is shut over the tube, a platen on the inside of the door presses against the IV tube to provide a backing surface against which the pumping members can occlude the tube. The platen is typically spring loaded, although not always, against the pumping mechanism so that one or more of the pumping fingers of the pumping mechanism occludes the tube once the door is shut over the tube. This then prevents free flow while the door is shut.

    [0004] This arrangement of the IV tube relative to the pumping mechanism requires that there be some means for preventing flow in the tube when the door of the pump is open. Merely opening the pump door would relieve the tube from the occluding pumping mechanism/platen combination and free flow could possibly occur. This could result in the uncontrolled infusion of medication into the patient under the influence of the static head pressure in the tube, or blood from the patient could flow back into the IV tube, Known devices for preventing the unwanted flow in the tube include manual clamps on the tube separate from the infusion pump, and automatic occluding devices mounted on the pump. The manual devices require some manipulation skill on the part of the attending technician, and there is always the chance that the technician will forget to properly time the manual clamping process of the tube before the door of the pump is opened. Furthermore, the door may be accidentally opened, resulting in free flow in the tube.

    [0005] Automatic devices mounted on the infusion pump for assisting in clamping and unclamping infusion tubes have improved. In particular, the reliability in timing the occlusion and release (unocclusion) of the tube with the disengagement and engagement, respectively, of tube with the pumping members has improved Typically, the action of opening the door is relied upon to initiate the occlusion of the IV tube by a clamp, and the action of closing the door is relied upon to initiate the release or unocclusion of the tube by an IV tube clamp. However, there still can occur the possibility of an inadvertent free flow of fluid through the IV tube due to operator error in regard to use of such devices.

    [0006] US 2002-0165503 discloses a fluid, infusion pump that includes a platen between an outer door and the pumping mechanism. The platen is located so that as the outer door of the pump is moved to the closed position, it moves the platen to position the fluid flow tube into occlusive contact with the pumping mechanism before the platen engages a flow stop formed integrally with the tube and releases the flow stop to permit fluid flow, thus avoiding a free flow condition, The door also includes a handle having a sear with a hook that engages the flow stop when the door is in the closed position. As the door is opened, the hook moves the flow stop to the occluded position before the platen is moved away from the tube thus preventing a free flow condition. The platen includes a flow stop release portion that is offset from the remainder of the platen that operatively engages a release tab on the flow stop to permit movement of the flow stop to the fluid flow configuration. The platen is mounted to the housing with a floating hinge and datum pins located on the face of the pumping mechanism precisely locate the platen into position with the pumping mechanism and thereby result in precise positioning of the fluid tube.

    [0007] US 6,364,279 discloses a closure device for closing a hose by pinching and in particular for closing a flexible tube or hose used in the medical field. Essentially, the device comprises a closure piece (62) provided with a circularly arcuate slot (70) which is extended by a circular orifice (76). The closure piece (62) can be rotated about a point O on a circle of radius (R) equal to the radius of the slot (70).

    [0008] Hence, those skilled in the art have identified a continuing need to provide an improved apparatus that will automatically and positively occlude an IV tube before the occluding pumping mechanism is disengaged from the tube, A further need has been recognized for an apparatus that will automatically and positively maintain the IV tube in an occluded state until after the occluding pumping mechanism is engaged with the tube. A still further need has been recognized for an apparatus that will reliably occlude the IV tube, that is inexpensive to manufacture, and is easy to use. Yet a further need has been recognized far an apparatus that can be manually operated between occluding and nonoccluding configurations. The present invention fulfills these needs and others.

    SUMMARY OF THE INVENTION



    [0009] Briefly and in general terms, the present invention is directed to a clamp apparatus for selectively preventing fluid flow through a resilient tube and comprises a base having a tube aperture at which the resilient tube may be located, the base having a longitudinal center line, a slide clamp slidably mountable on the base for movement between an occluding position and an open position, the slide clamp having a longitudinal center line, a clamp aperture formed in the slide clamp for receiving the tube therethrough, a constricted region formed in the clamp aperture, the constricted region occluding the tube to prevent fluid flow through the tube when the slide clamp is in the occluding position, an open region formed in the clamp aperture, the open region allowing fluid flow through the tube when the slide clamp is in the open position, a locking component formed on the slide clamp, and a flexible cantilevered locking arm mounted on the base, the locking arm having a release tab formed thereon but located at a position offset from the longitudinal center line of the base, the locking arm being biased toward a locking position wherein the locking arm engages the locking component of the slide clamp to prevent movement of the slide clamp from the occluding position to the open position, and the release tab being movable to deflect the locking arm wherein the locking arm is disengaged from the locking component to allow subsequent movement of the slide clamp from the occluding position to the open position according to claim 1.

    [0010] In accordance with another aspect of the invention, the tube aperture of the base slidably receives the resilient tube such that the base may be slid along the tube to a selected position when the slide clamp is in the open position.

    [0011] In other aspects of the invention, the locking arm further comprises a release tab for releasing the flexible arm from the slide clamp, to allow subsequent movement of the slide clamp from the occluding position to the open position. Further, the base comprises a stop surface located at a position adjacent the release tab to interfere with movement of the release tab beyond a preselected range of movement. The slide clamp comprises a detent into which the locking arm is biased and located when the slide clamp is in the occluding position, the detent being large enough to receive the locking arm without contact while the slide clamp is in the occluding position whereby the locking arm is under no stress. The slide clamp further comprises a ramp to receive the locking arm when the slide clamp is in the open position, the ramp formed to be deeper than the arm whereby the arm is not under stress when the slide clamp is in the flow position. The ramp is formed to guide the locking arm into a detent formed in the slide clamp as the slide clamp is being moved from the open position to the occluding position to thereby lock the slide clamp in the occluding position.

    [0012] In yet other aspects, the aperture of the slide clamp is approximately tear-drop shaped, the constricted region comprises an elongated slot portion, the flow region comprises a rounded portion, the tube is located in the slot portion when the slide clamp is in the occluding position, and the tube is located in the round portion when the slide clamp is in the open position.

    [0013] In additional detailed features, the tube aperture comprises a tube sleeve within which a resilient tube end may be permanently mounted. The tube aperture comprises a fluid passageway through the base, whereby the resilient tube is connected in fluid communication with the passageway. Further, the clamp apparatus comprises a pressure interface device located in line with the resilient tube, the pressure interface device having a pressure membrane mounted in a housing, the pressure membrane formed to conduct pressure increases and decreases of the resilient tubing to a pressure sensor located in a medical instrument.

    [0014] In further aspects in accordance with the invention, the slide clamp further comprises a front pushing flange large enough to receive a digit of an operator used to push the clamp apparatus into position in a medical infusion pump, the pushing surface being concave. The release tab of the locking arm is located at a position other than behind the pushing flange. In a much more detailed aspect, the release tab is located at a sideways position in relation to the pushing flange. Additionally, the base comprises a rounded mounting end whereby pressing the clamp into operative position in an infusion pump is facilitated.

    [0015] The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0016] 

    FIG. 1 is a perspective view of the automatic clamp apparatus in accordance with aspects of the present invention showing the slide clamp in the occlusion position at which it is partially withdrawn from the base;

    FIG. 2 is a front left-side perspective view of the slide clamp shown in FIG. 1 showing the aperture, the detent, the ramp, and the pushing flange;

    FIG. 3 is a bottom right-side perspective view of the slide clamp shown in FIG. 1 showing the aperture, the pushing flange, and the pulling projections;

    FIG. 4 is a top plan view of the slide clamp of FIGS. 1 through 3;

    FIG. 5 is a left side, partially cutaway view of the slide clamp of FIGS. 1 through 4 showing a pulling projection, the detent, and the ramp;

    FIG. 6 is a top, left side perspective view of the base showing a locking arm, a release tab, and a tube aperture;

    FIG. 7 is a bottom, right side perspective view of the base showing the locking arm and release tab;

    FIG. 8 is a right side plan view of the base showing the release tab;

    FIG. 9 is a cross-section left side view of the base showing the locking arm and release tab;

    FIG. 10 is a left side view of the base showing the tube aperture, the release tab, and a portion of the locking arm, also shown in the angle of the locking arm with the upper base surface;

    FIG. 11 is a bottom view of the base;

    FIG. 12 is a top, left side perspective view of the automatic clamp apparatus of FIG. 1 in which the slide clamp has been inserted fully into the base resulting in the flow configuration;

    FIG. 13 is an operational view in which the tube is occluded by the aperture of the slide clamp, but a release boss and a pushing boss are about to move the slide clamp to the open or flow position;

    FIG. 14 is an operational view in which the tube is unoccluded for flow and a pulling hook is about to pull the slide clamp to the occluding position; and

    FIG. 15 is a view of the clamp apparatus having a pressure interface device located as part of the tube upstream from the clamp for communicating the line pressure to a pressure sensor.


    DESCRIPTION OF PREFERRED EMBODIMENTS



    [0017] Referring now to the drawings with more particularity, in which like reference numerals refer to like or corresponding elements among the several views, FIG. 1 presents an automatic clamp apparatus 20 for intravenous (herein referred to as "IV") infusion sets used in pump devices. The clamp apparatus 20 comprises generally a relatively open, box shaped base or frame 22 and a mating slide clamp 24. Both parts can be formed by injection molding from various plastic materials. The solid body of the slide clamp 24 is shaped and sized to slide within the base 22. In the embodiment shown, the base 22 has a tower 26 formed on the top surface 28 of the base, with the tower extending upwardly from the base and substantially perpendicular to the base. The top end 30 of the tower 26 is formed as a female tube connector into which a resilient IV tube can be attached. A pumping tube or other type of fluid conduit can be attached to the base by other means if desired. The open bottom end 32 of the tower is attached to the base and it is also formed as a female tube connector into which an IV tube or other conduit can be attached. The IV tube and the pumping tube can be the same tube if desired, simply threading the IV tube through the tower, through the base, and through the slide clamp such that the automatic clamp apparatus 20 can be slid along the IV tube to a desired location.

    [0018] Referring now also to FIG. 2, the slide clamp 24 is penetrated from its top surface 34 to its bottom surface 36 by an elongated aperture 38. The elongated dimension of the aperture 38 is arranged on the slide clamp to be parallel to the direction of the relative sliding movement between the base 22 and the slide clamp 24. The aperture 38 of the slide clamp comprises an open portion 40 and an occluding portion 42. The open portion is large enough so that a tube received by the open portion would not be occluded whereas the occluding portion is small enough so that it would occlude a received tube. The width of the slot of the occluding portion is sufficiently small that a selected IV tube passing through the slot would be completely occluded and would remain occluded against a foreseeable range of fluid pressures in the IV tube. The range of pressure against which the tube would remain occluded would include at least the static head anticipated during normal use of the infusion apparatus.

    [0019] The slide clamp 24 also includes a pushing flange 44 at its front edge 46. The pushing flange is somewhat concave, although the "concave" surface may not necessarily be curved; it may in fact have converging straight surfaces or surfaces of other shapes. The purpose of the pushing flange is to guide the digit of an operator to the approximate center of the slide clamp for the purpose of mounting the entire automatic clamp apparatus 20 (FIG. 1) into an infusion pump. Such an operation may be seen by reference to U.S. Patent No. 6,629,955 to Morris, particularly FIG. 10. U.S. Patent No. 6,629,955 to Morris is incorporated herein by reference. Guiding the digit of an operator to the center of the pushing flange is more likely to result in the application of centerline force on the automatic clamp apparatus and thereby to result in the correct mounting of the clamp apparatus in the pump. For convenience, the shape of the pushing surface of the pushing flange 44 is referred to as "concave" although the surfaces may be other than curved, as discussed above. It will be noted that in this embodiment, the aperture 38 is also located on the longitudinal centerline 47 of the slide clamp.

    [0020] Also shown in FIG. 2 is a locking detent 48 having a locking detent edge 50. The particular operation of the detent will be shown later but its purpose is to prevent movement of the slide clamp from the occluding position to the open position in the base without intended action. Further shown is a ramp 52 at the front of the slide clamp for receiving a locking arm of the base when the slide clamp is in the open position.

    [0021] Referring now to the perspective view of FIG. 3 and the views of FIGS. 4 and 5, the bottom surface 36 of the slide clamp 24 includes pulling projections 30 that project downwardly from the bottom surface presenting a substantially vertical pulling face 56 to engage the latch on the door of the pump housing (not shown) to withdraw the slide clamp 24 partially out of engagement with the base 22 before the door is opened. Pulling or withdrawing the slide clamp partially out of the base moves the slide clamp from its open position to its occluding position (FIG. 1). The pushing flange 44 of the slide clamp also presents a substantially vertical pushing face against which the door of the pump or some other device pushes to fully insert the slide clamp into the base when the door of the pump is closing or after it has been closed. Pushing the slide clamp into full insertion with the base moves the slide clamp from its occluding position to its open position. Also shown in FIGS. 4 and 5 are the detent 48 and the ramp 52. Both are formed in the material of the slide clamp and the depth of both can be best seen from FIG. 5.

    [0022] Turning now to the base, there is shown in FIG. 6 the base 22 with a flexible cantilevered locking arm 60 that is molded into the top surface 28 of the base, with its distal free end 62 biased downwardly below the top surface 28 of the base. Biasing of the free end downwardly is accomplished by molding the locking arm in a downwardly sloped configuration, but the biasing could also be accomplished by the use of springs or other means. A release tab 64 is formed on the locking arm 60, projecting upwardly from the locking arm in the general direction of the tower 26. It will be noted that the release tab 64 is located at a position sideways to the tower 26. The release tab is also offset from the longitudinal centerline 66 of the base. The free end 62 of the locking arm 60 can be flexed upwardly by pressing the release tab 64 in a direction parallel to the centerline 66. Without departing from the spirit of the invention, multiple locking arms and tabs offset from the centerline of the base may be used in place of the ones shown.

    [0023] It should also be noted that the depth of the detent 48 and the size and angle of the locking arm 60 are carefully selected so that when the locking arm is located in the detent, it is unstressed. That is, it does not touch the bottom of the detent with any significant force. This is important in that if the locking arm is formed of plastic material or other material that exhibits "creep," it may change shape if it is exposed to constant stress for an extended period. For example, if the clamp apparatus were stored in the occluding position (FIG. 1) for an extended period where the locking arm was in contact with the bottom of a shallower detent and was under continual stress due to constant contact with the detent, the locking arm may creep to where that storage position is the new at rest position of the locking arm. The locking arm would then become less effective. Thus, forming the detent and locking arm as described above so that the arm is unstressed will result in a clamp apparatus that is unaffected by storage. Similarly, the ramp is also of a depth that leaves the locking arm unstressed when at the lowest point of the ramp, as is the case in the open position shown in FIG. 12.

    [0024] The base also includes its side edges 68 formed into rails 70 that lie parallel to the direction of the relative sliding movement of the slide clamp in the base (FIG. 1). When the slide clamp 24 is slidingly engaged with the base 22, the slide clamp fits in a sliding fashion through the two rail channels 72 in the base. Alignment of the slide clamp with the base is accomplished by the fit of the slide clamp into the rail channels. Turning now to FIG. 7, the rails 70 and channels 72 can be seen more clearly. Additionally, it will be noted that the entire proximal end 74 of the base is enclosed. The center section 76 has been left open to accommodate the pulling projections of the slide clamp, as previously shown. Also more clearly seen is the distal free end 62 of the locking arm, as well as the releasing tab 64.

    [0025] FIG. 8 shows a stop 78 formed on the top surface 28 of the base 22 that limits the range of movement of the release tab 64. In particular, a stop surface 80 is spaced away from the back of the releasing tab by a preselected distance so that the tab cannot be overstressed by bending it too far. Referring also to FIG. 9, a cross-section of the locking arm 60 with releasing tab 64 formed at its end is shown. It will be noted that the locking arm is molded as part of the base and is in a cantilever form. The releasing tab 64 is disposed at approximately ninety degrees to the locking arm but because the locking arm is formed at an angle to the upper 28 and the lower 82 surfaces of the base 22 so as to engage the slide clamp, the ninety degree angle of the releasing tab with the locking arm is other than ninety degrees to the top surface of the base. FIG. 9 more clearly illustrates the downward slope of the locking arm 60 to create the necessary downward bias to engage the detent 48 and locking edge 50 of the slide clamp to prevent the slide clamp from being moved to its open position until the locking arm 60 is moved out of the detent by intended action of the operator.

    [0026] Referring now to FIG. 10, a right side view of the base is provided. It will be seen that the angle of the top surface of the locking arm is approximately 172.86 degrees relative to the top surface 28 of the base. This is also seen in FIG. 9. It has been found that thickening the locking arm and providing the angles shown results in repeatable performance. That is, when a releasing boss 90 (shown in FIG. 13) presses against the releasing tab 64, the tab and locking arm will rise away from the base and therefore away from the mounted slide clamp thus releasing the slide clamp for movement to the open position. This is discussed below in more detail. FIG. 11 presents a bottom view of the base 22 showing more clearly the distal end 62 of the locking arm that is received by the detent 48 of the slide clamp 24. Further, FIG. 11 shows the aperture 49 through the base for the tube.

    [0027] FIG. 12 shows the assembled slide clamp 24 and base 22 into an operational automatic clamp apparatus 20 in accordance with aspects of the invention. Further, the clamp apparatus 20 is in the open position during which fluid may flow through the clamp apparatus. It will be seen that the distal free end 62 of the locking arm 60 resides in the ramp area 52, but the ramp is formed to be deep enough so that the distal free end 62 of the locking arm is not touching the material of the base and therefore, the locking arm is in an unstressed condition. In this configuration, the clamp apparatus 20 is in its smallest form thereby fitting into a pump with a closed door.

    [0028] FIGS. 13 and 14 show in general how the automatic clamp apparatus 20 in accordance with aspects of the invention interacts with the door of a pump housing. FIG. 13 shows the slide clamp 24 in its occluding position relative to the base 22, with the slide clamp partially withdrawn from the base and the distal free end 62 of the locking arm 60 engaging the locking detent 48 (not shown) to hold the slide clamp in its occluding position. FIG. 14 shows the slide clamp in its open position with the slide clamp fully inserted within the base and the distal free end 62 of the locking arm flexed upwardly a sufficient amount to clear the detent 48.

    [0029] Operative elements of the door and latch mechanism are shown schematically and designated as elements 90, 92, and 94, to illustrate their interaction with the automatic clamp apparatus of the present invention. A releasing boss 90 can be formed on the door and positioned to contact the release tab 64 as the door is moved to the closed position, and to press the release tab up and back. A pushing boss 92 can be formed on the latch mechanism and positioned to contact the pushing flange 44 on the slide clamp 24 as the latch is engaged to push the slide clamp from its occluding position (FIG. 13) to its open position (FIG. 14). Finally, one or more pulling hooks 94 can be formed on the latch mechanism and positioned to contact the pulling projections 54 as the latch is disengaged to pull the slide clamp 24 from its open position to its occluding position.

    [0030] The releasing boss 90 and the pushing boss 92 of the door move generally to the right direction as seen in FIG. 13 when the door of the pump is moved to the closed position. The pulling hook 94 of the latch mechanism can be made to move generally to the left as seen in FIG. 14 when the latch is being disengaged, and to the right when the latch is being engaged, it being understood that other elements (not shown) of the latch mechanism perform the actual latching of the door in the shut position. In addition, the pulling hook 94 can rotate in the clockwise direction from the position shown, relative to the remainder of the latch mechanism, against a spring bias. For convenience, the conduit through the automatic clamp apparatus 20 is shown as a tube 96 in FIG. 13 and 14. In FIG. 13, the tube 96 is occluded by the slide clamp aperture and is spread into the occluding slot of that aperture. In FIG. 14, the tube is in the flow configuration. As mentioned above, a tube may or may not be used as the conduit through the clamp apparatus 20. A tower may be used with parts of tube formed to the tower.

    [0031] Referring briefly to FIG. 15, the inclusion of a pressure interface device 100 upstream of the automatic clamp apparatus 20 is shown. This pressure interface device may take the form of a pressure diaphragm having a size and configuration to be mounted to a pressure sensor that is a part of the infusion pump to which the clamp apparatus is to be mounted. Such a pressure diaphragm device is shown in U.S. Patent No. 4,398,542 to Cunningham, and incorporated herein by reference. A sensor usable with such a pressure diaphragm is shown in U.S. Patent No. 4,404,440 to Busche, also incorporated herein by reference. Mounting such a pressure diaphragm in line with the automatic clamp apparatus of the invention would restrict movement of the clamp apparatus along the line since it will need to be adjacent the pressure diaphragm to be fitted into the pump. In such a case, the tower 26 may be used as a mount for the pressure diaphragm device.

    OPERATION



    [0032] To use the automatic clamp apparatus 20 of the present invention, the slide clamp 24 is assured to be in the occluded position, as shown in FIG. 1. Because the locking arm 60 is located in the detent 48, the slide clamp cannot be moved from the occluding position to the open position unless the release tab 64 is actuated. While in the detent, the locking arm is unstressed. The upstream end of the IV tube 96 is connected to a fluid supply (not shown) of the chosen fluid to be pumped. The administration set containing the automatic clamp apparatus of the invention may be primed if necessary by the operator pressing a digit against the release tab to move it and the locking arm upwards out of the detent and another digit against the pushing flange to move the slide clamp to the open position. As the slide clamp is inserted into the base, the locking arm moves down the ramp 52 to the bottom of the ramp (FIG. 12) where it is unstressed. Priming may now occur. Once primed, the pushing flange is grasped by the operator and withdrawn from the base to restore the slide clamp to the occlusion position as shown in FIG. 1 so that the free flow of fluid through the IV tube cannot occur.

    [0033] The door of the pump housing is opened and the automatic clamp apparatus 20 and tubing above and below the clamp apparatus 20 are installed into the pump appropriately. The pushing flange is used by the operator to receive a digit of the operator for pushing the clamp apparatus into the appropriate cavity of the pump. The clamp apparatus should remain in the occlusion configuration during this installation into the pump. Because the release tab is off center in relation to the pushing flange, the chances of the operator pressing it instead or with, the pushing flange are greatly reduced.

    [0034] The upstream and downstream tubing is now engaged with any other devices that exist, such as an air-in-line sensor, pressure sensors, etc. Especially, the pumping tube 96 is placed in contact with the pumping mechanism, and the door of the pump is then shut. FIG. 13 shows the slide clamp 24 in its occluding position, with the release boss 90 about to contact the release tab 64 as the door of the pump is shut. As the door is completely shut, the release boss 90 presses the release tab 64 upward thereby flexing the locking arm 60 upward and out of the detent 48 thereby permitting movement of the slide clamp so that it can be inserted into the base. After the door is completely shut, the latching mechanism is latched, causing the pushing boss 92 to push the slide clamp 24 and insert it into the base to its open position as shown in FIG. 12. FIG. 14 shows the slide clamp 24 in its open position, with the pulling hook 94 having pivoted behind the pulling projection 54. The pump can then be operated in the conventional fashion to purge the IV tube 96 of air, and the IV tube 96 can be connected to a venous access site.

    [0035] When the pump door is to be opened, the boss 92 and the hook 94 will be moved to the left, causing the pulling hooks 94 to contact the pulling projection 54 of the slide clamp 24 and withdraw the slide clamp 24 from the base to its occluding position. The latching mechanism can be constructed by known means so that only after this occlusion occurs will the door be unlatched. At this time, the door can be opened. The locking arm 60 having engaged the locking detent 48 maintains the slide clamp 24 in its occluding position, even if the slide clamp 24 is pushed toward the base 22 with considerable force.

    [0036] The latching mechanism can also be constructed by known means so that when the door has been unlatched, the latching mechanism can not be moved back to its latched position until the door has been shut. Therefore, if the door is to be shut, the releasing boss 90 will press the release tab 64 upward to release the locking arm 60 from engagement with the detent 48, and the slide clamp 24 can be subsequently moved to the open position as explained before.

    [0037] While the particular automatic clamp apparatus as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as described in the appended claims.


    Claims

    1. A clamp apparatus (20) for selectively preventing fluid flow through a resilient tube, comprising:

    a base (22) having a tube aperture (26) at which the resilient tube may be located, the base having a longitudinal center line (66);

    a slide clamp (24) slidably mountable on the base (22) for movement between an occluding position and an open position, the slide clamp having a longitudinal center line (47);

    a clamp aperture (38) formed in the slide clamp for receiving the tube therethrough;

    a constricted region (42) formed in the clamp aperture (38), the constricted region (42) occluding the tube to prevent fluid flow through the tube when the slide clamp (24) is in the occluding position;

    an open region (40) formed in the clamp aperture (38), the open region (40) allowing fluid flow through the tube when the slide clamp (24) is in the open position;

    a flexible cantilevered locking arm (60) mounted on the base (22), the locking arm being biased toward a locking position to prevent movement of the slide clamp (24) from the occluding position to the open position, the locking arm (60) being deflectable to allow subsequent movement of the slide clamp (24) from the occluding position to the open position; and

    a detent (48) in the slide clamp (24) into which the locking arm (60) is biased to the locking position and into which the locking arm (60) is located when the slide clamp (24) is in the occluding position to prevent the slide clamp from moving from the occluding position;

    the apparatus being characterized in that:

    the detent (48) is large enough to receive the locking arm (60) such that the locking arm is unstressed while in the detent; and

    the slide clamp (24) further comprises a ramp (52) to receive the locking arm (60) when the slide clamp (24) is in the open position, the ramp (52) formed to be deeper than the arm whereby the arm (60) is unstressed when the slide clamp (24) is in the flow position.


     
    2. The clamp apparatus of claim 1 wherein the tube aperture (26) of the base (22) slidably receives the resilient tube such that the base may be slid along the tube to a selected position when the slide clamp is in the open position.
     
    3. The clamp apparatus of claim 1 wherein the locking arm (60) further comprises a release tab (64) for releasing the flexible arm (60) from the slide clamp (24), to allow subsequent movement of the slide clamp (24) from the occluding position to the open position.
     
    4. The clamp apparatus of claim 3 wherein the base (22) further comprises a stop surface (80) located at a position adjacent the release tab (64) to interfere with movement of the release tab beyond a preselected range of movement.
     
    5. The clamp apparatus of claim 3 wherein the release tab (64) is located at a position offset from the longitudinal center line (66) of the base (22).
     
    6. The clamp apparatus of claim 5 wherein the release tab (64) is disposed for deflecting the flexible arm (60) out of the detent (48) to allow subsequent movement of the slide clamp (24) from the occluding position to the open position.
     
    7. The clamp apparatus of claim 1 wherein the ramp (52) is formed to guide the locking arm (60) into a detent formed in the slide clamp (24) as the slide clamp is being moved from the open position to the occluding position to thereby lock the slide clamp in the occluding position.
     
    8. The clamp apparatus of claim 1 wherein:

    the aperture (38) is approximately tear-drop shaped; the constricted region (42) comprises an elongated slot portion;

    the flow region (40) comprises a rounded portion; the tube is located in the slot portion (42) when the slide clamp (24) is in the occluding position; and

    the tube is located in the round portion (40) when the slide clamp (24) is in the open position.


     
    9. The clamp apparatus of claim 1 wherein the tube aperture (26) comprises a tube sleeve within which a tube end may be permanently mounted.
     
    10. The clamp apparatus of claim 1 wherein the tube aperture (26) comprises a fluid passageway through the base, whereby the resilient tube is connected in fluid communication with the passageway.
     
    11. The clamp apparatus of claim 1 further comprising a pressure interface device (100) located between the resilient tube and the base (22), the pressure interface device (100) having a pressure membrane mounted in a housing, the pressure membrane formed to conduct pressure increases and decreases of the resilient tubing to a pressure sensor.
     
    12. The clamp apparatus of claim 1 wherein the slide clamp (24) further comprises a front pushing flange (44) large enough to receive a digit of an operator used to push the clamp apparatus into position in a medical infusion pump, the pushing surface being concave.
     
    13. The clamp apparatus of claim 12 wherein the release tab (64) is located at a position other than behind the pushing flange (44).
     
    14. The clamp apparatus of claim 13 the release tab (64) is located at a sideways position in relation to the pushing flange (44).
     
    15. The clamp apparatus of claim 1 wherein:

    the locking arm (60) further comprises a release tab (64) for releasing the flexible arm (60) from the slide clamp (24), to allow subsequent movement of the slide clamp (24) from the occluding position to the open position;

    the base (22) further comprises a stop surface (80) located at a position adjacent the release tab (64) to interfere with movement of the release tab beyond a preselected range of movement;

    the slide clamp (24) comprises a ramp (52) to receive the locking arm (60) when the slide clamp is in the open position, the ramp (52) formed to be deeper than the locking arm (60) whereby the locking arm is not under stress when the slide clamp (24) is in the flow position, the ramp (52) further formed to guide the locking arm (60) into the detent as the slide clamp is being moved from the open position to the occluding position to thereby lock the slide clamp (24) in the occluding position;

    the slide clamp (24) further comprises a front pushing flange (44) large enough to receive a digit of an operator used to push the clamp apparatus into position in a medical device, the pushing surface being concave; and the release tab (64) is located at a position other than behind the pushing flange.


     
    16. The clamp apparatus of claim 15 wherein the release tab (64) is located at a sideways position in relation to the pushing flange (44).
     


    Ansprüche

    1. Klemmvorrichtung (20), die dazu dient, es selektiv zu verhindern, dass Fluid durch eine elastische Röhre fließt, wobei die Vorrichtung folgendes umfasst:

    eine Basis (22) mit einer Röhrenöffnung (26), an welcher sich die elastische Röhre befinden kann, wobei die Basis eine longitudinale Mittellinie (66) aufweist;

    eine Schiebeklemme (24), die verschiebbar an der Basis (22) angebracht ist, für eine Bewegung zwischen einer verschließenden Position und einer offenen Position, wobei die Schiebeklemme eine longitudinale Mittellinie (47) aufweist;

    eine Klemmenöffnung (48), die in der Schiebeklemme zur Aufnahme der Röhre dort hindurch ausgebildet ist;

    einen verengten Bereich (42), der in der Klemmenöffnung (38) ausgebildet ist, wobei der verengte Bereich (42) die Röhre verschließt, um einen Fluidfluss durch die Röhre zu verhindern, wenn sich die Schiebeklemme (24) an der verschließenden Position befindet;

    einen offenen Bereich (40), der in der Klemmenöffnung (38) ausgebildet ist, wobei der offene Bereich (40) einen Fluidfluss durch die Röhre zulässt, wenn sich die Schiebeklemme (24) an der offenen Position befindet;

    einen flexiblen Auslegerverriegelungsarm (60), der an der Basis (22) angebracht ist, wobei der Verriegelungsarm an eine Verriegelungsposition vorbelastet ist, um eine Bewegung der Schiebeklemme (24) aus der verschließenden Position an die offene Position zu verhindern, wobei der Verriegelungsarm (60) ablenkbar ist, um eine folgende Bewegung der Schiebeklemme aus der verschließenden Position an die offene Position zu verhindern; und

    eine Feststelleinrichtung (48) in der Schiebeklemme (24), in welche der Verriegelungsarm (60) an die Verriegelungsposition vorbelastet ist und in welcher der Verriegelungsarm (60) positioniert ist, wenn sich die Schiebeklemme (24) an der verschließenden Position befindet, um es zu verhindern, dass sich die Schiebeklemme aus der verschließenden Position bewegt;

    wobei die Vorrichtung dadurch gekennzeichnet ist, dass:

    die Feststelleinrichtung (48) groß genug ist für die Aufnahme des Verriegelungsarms (60), so dass der Verriegelungsarm unbelastet ist, wenn er sich in der Feststelleinrichtung befindet; und

    wobei die Schiebeklemme (24) ferner eine Rampe (52) zur Aufnahme des Verriegelungsarms (60) umfasst, wenn sich die Schiebeklemme (24) an der offenen Position befindet, wobei die Rampe (52) so ausgebildet ist, dass sie tiefer ist als der Arm, wodurch der Arm (60) unbelastet ist, wenn sich die Schiebeklemme (24) in der Flussposition befindet.


     
    2. Klemmvorrichtung nach Anspruch 1, wobei die Röhrenöffnung (26) der Basis (22) gleitfähig die elastische Röhre aufnimmt, so dass die Basis entlang der Röhre an eine ausgewählte Position geschoben werden kann, wenn sich die Schiebeklemme an der offenen Position befindet.
     
    3. Klemmvorrichtung nach Anspruch 1, wobei der Verriegelungsarm (60) ferner einen Entriegelungsstreifen (64) zur Entriegelung des flexiblen Arms (60) von der Schiebeklemme (24) umfasst, um eine folgende Bewegung der Schiebeklemme (24) von der verschließenden Position an die offene Position zu ermöglichen.
     
    4. Klemmvorrichtung nach Anspruch 3, wobei die Basis (22) ferner eine Anschlagoberfläche (80) umfasst, die sich an einer Position neben dem Entriegelungsstreifen (64) befindet, um die Bewegung des Entriegelungsstreifens über einen vorausgewählten Bewegungsbereich hinaus zu beeinträchtigen.
     
    5. Klemmvorrichtung nach Anspruch 3, wobei sich der Entriegelungsstreifen (64) an einer von der longitudinalen Mittellinie (66) der Basis (22) versetzten Position befindet.
     
    6. Klemmvorrichtung nach Anspruch 5, wobei der Entriegelungsstreifen (64) so angeordnet ist, dass er den flexiblen Arm (60) aus der Feststelleinrichtung (48) ablenkt, um eine folgende Bewegung der Schiebeklemme (24) aus der verschließenden Position an die offene Position zu ermöglichen.
     
    7. Klemmvorrichtung nach Anspruch 1, wobei die Rampe (52) so ausgebildet ist, dass sie den Verriegelungsarm (60) in eine Feststelleinrichtung führt, die in der Schiebeklemme (24) ausgebildet ist, wenn die Schiebeklemme von der offenen Position an die verschließende Position bewegt wird, um dadurch die Schiebeklemme an der verschließenden Position zu verriegeln.
     
    8. Klemmvorrichtung nach Anspruch 1, wobei:

    die Öffnung (38) ungefähr die Form einer Träne aufweist; wobei der verengte Bereich (42) einen länglichen Schlitzteil umfasst;

    wobei der Flussbereich (40) einen abgerundeten Teil umfasst; wobei sich die Röhre in dem Schlitzteil (42) befindet, wenn sich die Schiebeklemme (24) an der verschließenden Position befindet; und

    wobei sich die Röhre in dem runden Teil (40) befindet, wenn sich die Schiebeklemme (24) an der offenen Position befindet.


     
    9. Klemmvorrichtung nach Anspruch 1, wobei die Röhrenöffnung (26) eine Röhrenhülle umfasst, in welcher ein Röhrenende dauerhaft angebracht sein kann.
     
    10. Klemmvorrichtung nach Anspruch 1, wobei die Röhrenöffnung (26) einen Fluiddurchgang durch die Basis umfasst, wobei die elastische Röhre in Fluidübertragungsverbindung mit dem Durchgang verbunden ist.
     
    11. Klemmvorrichtung nach Anspruch 1, wobei diese ferner eine Druckschnittstellenvorrichtung (100) umfasst, die sich zwischen der elastischen Röhre und der Basis (22) befindet, wobei die Druckschnittstellenvorrichtung (100) eine Druckmembran aufweist, die in einem Gehäuse angebracht ist, wobei die Druckmembran so ausgebildet ist, dass sie Druckerhöhungen und Druckminderungen der elastischen Röhre an einen Drucksensor ausführt.
     
    12. Klemmvorrichtung nach Anspruch 1, wobei die Schiebeklemme (24) ferner einen vorderen Druckflansch (44) umfasst, der groß genug ist, um einen Finger einer Bedienungsperson aufzunehmen, der verwendet wird, um die Klemmvorrichtung an eine Position in einer medizinischen Infusionspumpe zu drücken, wobei die Druckoberfläche konkav ist.
     
    13. Klemmvorrichtung nach Anspruch 12, wobei sich der Entriegelungsstreifen (64) an einer anderen Position als hinter dem Druckflansch (44) befindet.
     
    14. Klemmvorrichtung nach Anspruch 13, wobei sich der Entriegelungsstreifen an einer seitlichen Position im Verhältnis zu dem Druckflansch (44) befindet.
     
    15. Klemmvorrichtung nach Anspruch 1, wobei:

    der Verriegelungsarm (60) ferner einen Entriegelungsstreifen (64) zur Entriegelung des flexiblen Arms (60) von der Schiebeklemme (24) umfasst, um eine folgende Bewegung der Schiebeklemme (24) von der verschließenden Position an die offene Position zu ermöglichen;

    die Basis (22) ferner eine Anschlagoberfläche (80) umfasst, die sich an einer Position neben dem Entriegelungsstreifen (64) befindet, um die Bewegung des Entriegelungsstreifens über einen vorausgewählten Bewegungsbereich hinaus zu beeinträchtigen;

    die Schiebeklemme (24) eine Rampe (52) zur Aufnahme des Verriegelungsarms (60) umfasst, wenn sich die Schiebeklemme (24) an der offenen Position befindet, wobei die Rampe (52) so ausgebildet ist, dass sie tiefer ist als der Arm, wodurch der Arm (60) unbelastet ist, wenn sich die Schiebeklemme (24) in der Flussposition befindet, wobei die Rampe (52) ferner so ausgebildet ist, dass sie den Verriegelungsarm (60) in eine Feststelleinrichtung führt, die in der Schiebeklemme (24) ausgebildet ist, wenn die Schiebeklemme von der offenen Position an die verschließende Position bewegt wird, um dadurch die Schiebeklemme (24) an der verschließenden Position zu verriegeln;

    wobei die Schiebeklemme (24) ferner einen vorderen Druckflansch (44) umfasst, der groß genug ist, um einen Finger einer Bedienungsperson aufzunehmen, der verwendet wird, um die Klemmvorrichtung an eine Position in einer medizinischen Infusionspumpe zu drücken, wobei die Druckoberfläche konkav ist; und wobei sich der Entriegelungsstreifen (64) an einer anderen Position als hinter dem Druckflansch befindet.


     
    16. Klemmvorrichtung nach Anspruch 15, wobei sich der Entriegelungsstreifen an einer seitlichen Position im Verhältnis zu dem Druckflansch (44) befindet.
     


    Revendications

    1. Appareil pinceur (20) pour empêcher de façon sélective un écoulement de fluide à travers un tube élastique, comprenant :

    une base (22) ayant une ouverture de tube (26) au niveau de laquelle le tube élastique peut être situé, la base ayant une ligne centrale longitudinale (66) ;

    une pince coulissante (24) montée coulissante sur la base (22) pour se déplacer entre une position de bouchage et une position ouverte, la pince coulissante ayant une ligne centrale longitudinale (47) ;

    une ouverture de pince (38) formée dans la pince coulissante pour recevoir le tube au travers ;

    une région rétrécie (42) formée dans l'ouverture de pince (38), la région rétrécie (42) bouchant le tube pour empêcher l'écoulement de fluide à travers le tube lorsque la pince coulissante (24) est dans la position de bouchage ;

    une région ouverte (40) formée dans l'ouverture de pince (38), la région ouverte (40) autorisant l'écoulement de fluide à travers le tube lorsque la pince coulissante (24) est dans la position ouverte ;

    un bras de verrouillage en saillie flexible (60) monté sur la base (22), le bras de verrouillage étant rappelé vers une position de verrouillage pour empêcher le mouvement de la pince coulissante (24) de la position de bouchage à la position ouverte, le bras de verrouillage (60) étant fléchissant pour permettre le mouvement subséquent de la pince coulissante (24) de la position de bouchage à la position ouverte ; et

    un cliquet (48) dans la pince coulissante (24) dans lequel le bras de verrouillage (60) est rappelé à la position de verrouillage et dans lequel le bras de verrouillage (60) est situé lorsque la pince coulissante (24) est dans la position d'occlusion pour empêcher la pince coulissante de quitter la position de bouchage ;

    l'appareil étant caractérisé en ce que :

    le cliquet (48) est suffisamment grand pour recevoir le bras de verrouillage (60) de sorte que le bras de verrouillage ne subisse pas de contrainte lorsqu'il se trouve dans le cliquet ; et

    la pince coulissante (24) comprend en outre une rampe (52) pour recevoir le bras de verrouillage (60) lorsque la pince coulissante (24) est dans la position ouverte, la rampe (52) étant formée pour être plus profonde que le bras moyennant quoi le bras (60) ne subit pas de contrainte lorsque la pince coulissante (24) est dans la position d'écoulement.


     
    2. Appareil pinceur selon la revendication 1, l'ouverture de tube (26) de la base (22) recevant de façon coulissante le tube élastique de sorte que la base puisse être glissée le long du tube à une position sélectionnée lorsque la pince coulissante est dans la position ouverte.
     
    3. Appareil pinceur selon la revendication 1, le bras de verrouillage (60) comprenant en outre une languette de libération (64) pour libérer le bras flexible (60) de la pince coulissante (24), afin de permettre le déplacement subséquent de la pince coulissante (24) de la position de bouchage à la position ouverte.
     
    4. Appareil pinceur selon la revendication 3, la base (22) comprenant en outre une surface de butée (80) située à une position adjacente à la languette de libération (64) pour interférer avec le déplacement de la languette de libération au-delà d'une plage de déplacement présélectionnée.
     
    5. Appareil pinceur selon la revendication 3, la patte de libération (64) étant située à une position décalée par rapport à la ligne centrale longitudinale (66) de la base (22).
     
    6. Appareil pinceur selon la revendication 5, la languette de libération (64) étant disposée pour fléchir le bras flexible (60) hors du cliquet (48) pour permettre le déplacement subséquent de la pince coulissante (24) de la position de bouchage à la position ouverte.
     
    7. Appareil pinceur selon la revendication 1, la rampe (52) étant formée pour guider le bras de verrouillage (60) dans un cliquet formé dans la pince coulissante (24) alors que la pince coulissante est déplacée de la position ouverte à la position de bouchage pour ainsi verrouiller la pince coulissante dans la position de bouchage.
     
    8. Appareil pinceur selon la revendication 1 :

    l'ouverture (38) étant approximativement en forme de larme ; la région rétrécie (42) comprenant une partie fente allongée ;

    la région d'écoulement (40) comprenant une partie arrondie ; le tube étant situé dans la partie fente (42) lorsque la pince coulissante (24) est dans la position de bouchage ; et

    le tube étant situé dans la partie arrondie (40) lorsque la pince coulissante (24) est dans la position ouverte.


     
    9. Appareil pinceur selon la revendication 1, l'ouverture de tube (26) comprenant un manchon de tube dans lequel une extrémité de tube peut être montée à demeure.
     
    10. Appareil pinceur selon la revendication 1, l'ouverture de tube (26) comprenant un passage de fluide à travers la base, moyennant quoi le tube élastique est relié en communication fluidique avec le passage.
     
    11. Appareil pinceur selon la revendication 1, comprenant en outre un dispositif d'interface de pression (100) situé entre le tube élastique et la base (22), le dispositif d'interface de pression (100) ayant une membrane de pression montée dans un boîtier, la membrane de pression étant formée pour procéder à des augmentations et à des diminutions de pression du tube élastique en fonction d'un capteur de pression.
     
    12. Appareil pinceur selon la revendication 1, la pince coulissante (24) comprenant en outre une bride de poussée avant (44) suffisamment grande pour recevoir le doigt d'un opérateur utilisé pour pousser l'appareil pinceur en position dans une pompe à perfusion médicale, la surface de poussée étant concave.
     
    13. Appareil pinceur selon la revendication 12, la patte de libération (64) étant située à une position autre que derrière la bride de poussée (44).
     
    14. Appareil pinceur selon la revendication 13, la patte de libération (64) étant située à une position latérale par rapport à la bride de poussée (44).
     
    15. Appareil pinceur selon la revendication 1 :

    le bras de verrouillage (60) comprenant en outre une languette de libération (64) pour libérer le bras flexible (60) de la pince coulissante (24), afin de permettre le déplacement subséquent de la pince coulissante (24) de la position de bouchage à la position ouverte ;

    la base (22) comprenant en outre une surface de butée (80) située à une position adjacente à la languette de libération (64) pour interférer avec le déplacement de la languette de libération au-delà d'une plage de déplacement présélectionnée ;

    la pince coulissante (24) comprenant une rampe (52) pour recevoir le bras de verrouillage (60) lorsque la pince coulissante est dans la position ouverte, la rampe (52) étant formée pour être plus profonde que le bras de verrouillage (60) moyennant quoi le bras de verouillage n'est pas soumis à tension lorsque la pince coulissante (24) est dans la position d'écoulement, la rampe (52) étant en outre formée pour guider le bras de verrouillage (60) dans le cliquet alors que la pince coulissante est déplacée de la position ouverte à la position de bouchage pour ainsi verrouiller la pince coulissante (24) dans la position de bouchage ;

    la pince coulissante (24) comprenant en outre une bride de poussée avant (44) suffisamment grande pour recevoir le doigt d'un opérateur utilisé pour pousser l'appareil pinceur en position dans un dispositif médical, la surface de poussée étant concave ; et la languette de libération (64) étant située à une position autre que derrière la bride de poussée.


     
    16. Appareil pinceur selon la revendication 15, la patte de libération (64) étant située à une position latérale par rapport à la bride de poussée (44).
     




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    Cited references

    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description