Abstract:
The invention relates to a tilt and slide cover in a vehicle roof. The tilt and slide cover comprises a cover and a frame, which is supported in lateral guides of a roof opening. The special feature of the tilt and slide cover lies in the fact that the cover is arranged relatively moveable in relation to the frame and can be locked to and released from this. The frame comprises a plastic section, into which the slide guide and other fittings such as slide cheek holders or the like can be integrated in one piece. It is also possible to fix the rear water collection channel directly on the frame.

Description:
FIELD OF TH INVENTION 
     This invention relates generally to wound healing, and more specifically to healing of wounds by negative pressure drainage. 
     BACKGROUND OF THE INVENTION 
     Negative pressure applied to a wound enhances drainage of fluids or exudate from the wound and promotes tissue growth and wound healing. This method of healing (known as “cupping”) was exercised since the times of ancient Greek physicians until the 19th century. 
     WO 96/05873 describes a therapeutic apparatus for stimulating healing of wounds. The apparatus comprises a porous foamed pad which is sealed on the wound and connected by a tube to an inlet of a canister. A vacuum pump is connected to an outlet of the canister. A bacterial filter positioned over the outlet of the canister protects the vacuum pump from contamination by wound drainage fluids sucked into the canister. The pump, the canister and control circuitry are disposed in a case. 
     WO 97/18007 discloses a portable wound treatment apparatus using a similar arrangement of a porous pad, canister and vacuum pump. The canister and the pump are in one housing which accommodates also the control circuitry and is wearable on a harness or a belt. 
     U.S. Pat. No. 6,648,862 describes a portable vacuum desiccator using a similar arrangement as above, the canister being formed as a cartridge containing a trapping agent (desiccator). The vacuum pump and the canister may be integrated and detachable from the pump motor and circuitry. 
     Current negative pressure wound drainage systems such as the ones described above suffer from the following deficiencies:
         Since the negative pressure applied to the wound area is created by pump suction, the flow into the pump is likely to contaminate the pump, or conversely, to require costly and complex methods of isolating the pump from the wound exudate such as antibacterial filters.   The wound exudate is collected in a rigid canister, which must be large enough to prevent it from overflowing, and thus it is bulky and an inconvenient burden for ambulatory patients, who carry a portable system with them.   Conventional wound drainage systems utilize an air tight seal of the wound, which is helpful in obtaining and maintaining negative pressure, but requires a pressure relief or bleed valve to produce the pressure cycling desirable to obtain accelerated wound closure, as described in WO 96/05873.   A sealed wound dressing or enclosure, when under negative pressure, will promote migration of the exudate toward the negative pressure source, through the connecting tube, which may occlude, should the exudate coagulate.   The need to monitor and control the negative pressure level in conventional systems requires the use of a vacuum transducer, gage or relief valve, which must be connected to the suction tube, which is subject to contamination. Cleaning, disinfecting or isolating the negative pressure monitoring or controlling device are complex, costly and un-reliable.       

     SUMMARY OF THE INVENTION 
     It is the purpose of this invention to alleviate all the above listed deficiencies, by providing a wound drainage enclosure and vacuum system, which are impervious to contamination and easy to use. 
     In accordance with a first aspect of the present invention, there is provided an enclosure for draining an open wound from liquids exuded therefrom. The enclosure is attachable to the wound circumference so as to define a confined volume, and has an outlet, for example formed as a nipple, connectable by means of a tube to an inlet of a vacuum pump so that negative pressure may be created in said confined volume. One or more bleeding holes are provided in the enclosure or adjacent to its outlet such that ambient air can enter the tube and flow together with the exuded liquids when negative pressure is present. Ambient pressure may be restored in the confined volume when the vacuum pump is not operating. 
     The bleeding hole in the enclosure may be a calibrated orifice or other flow restrictors providing for controlled flow of ambient air into the enclosure or into its outlet. For instance, a hole plugged with open cell foam or an open pore sintered metal plug, which restrict the flow, but are not susceptible to plugging as is a small orifice. 
     The bleeding hole renders the wound closure vented or non-airtight, as distinguishable from conventional wound closures. The flow of air from the bleeding hole in the wound closure, in response to the negative pressure created by the vacuum pump, facilitates the removal of exudate, which might otherwise coagulate, dry-up and occlude the tubing. 
     According to another aspect of the present invention, there is provided a method for draining an open wound from liquids exuded therefrom. The method includes:
         providing an enclosure and sealing it to the wound circumference so as to define a confined volume,   connecting the confined volume to a vacuum pump,   connecting a waste container for collection of drained liquids to the vacuum pump, and   operating said vacuum pump to draw the exuded liquids from the wound.       

     The method is characterized in that the confined volume is connected to an inlet of the vacuum pump and the waste container is connected to an outlet of the vacuum pump such that the drained liquids flow through said vacuum pump. 
     The method may include employment of an enclosure with bleeding orifices so that ambient air is allowed to enter the tube and flow together with the drained exuded liquids. 
     Preferably, gases are separated and released from the drained exuded liquids. 
     According to a further aspect of the present invention, there is provided a vacuum system for practicing the above method. The vacuum system may use a totally disposable vacuum pump, together with a waste collection bag, as disclosed in WO03016719. The vacuum pump is a two-chambered diaphragm pump adapted for pumping gases and liquids and/or any combination thereof The vacuum pump is capable of pumping air and fluid which enter its inlet port, to a waste bag attached to its outlet port. The waste bag is vented to the atmosphere, such that it collects only the fluids which enter it. 
     The vacuum system may be adapted to be carried by an ambulatory patient. 
     According with a next aspect of the present invention, there is provided a disposable assembly for draining an open wound from liquids exuded therefrom. The assembly comprises an enclosure attachable to the wound circumference so as to define a confined volume, a vacuum pump unit connected to the enclosure so that negative pressure may be created in the confined volume, and a waste container connected to the vacuum pump unit. The vacuum pump unit has means for detachably attaching to a drive unit for operating the pump unit. The enclosure is connected to an inlet of the vacuum pump unit and the waste container is connected to an outlet of the vacuum pump unit, such that when the vacuum pump unit is operated the drained liquids flow therethrough. 
     Preferably, the pump unit and the drive unit are adapted for attaching and detaching by simple hand manipulations. 
     The enclosure may have bleeding holes as described above. 
     The vacuum pump unit is preferably a two-chambered diaphragm pump adapted for pumping gases and liquids and/or any combination thereof. 
     The waste container may contain a porous media adapted to soak up the drained liquids and may be in the form of a collapsible or foldable bag. 
     The drained liquids and air contact only the parts of the disposable assembly. The drained exuded liquids may then be disposed of together with the disposable assembly. More specifically, the pump unit is disposed of after use, together with the tubing connected to it, as well as the waste bag connected, with its content, and with the wound closure which may be connected to the pump unit via the tube. 
     In accordance with yet another aspect of the present invention, there is provided a vacuum system as described above where the vacuum pump has a drive unit and a control block adapted to power the drive unit so that a predetermined level of negative pressure is maintained in the confined volume. The control block has a sensor for sensing working parameters of the drive unit and means for deriving the level of negative pressure in the confined volume from these working parameters, in order to maintain said predetermined level. The sensor has no fluid connection with the confined volume. 
     For example, the drive unit may comprise a direct current electric motor and the sensor may sense the electric current driving the motor. The same function of negative pressure control may be accomplished by an adjustable torque limiting clutch, placed between the motor output shaft and the pump. 
     The control block may be provided with alarm means to warn the user if the predetermined level of negative pressure is not maintained. 
     If the vacuum pump comprises a disposable pump unit and the drive unit is detachably attachable to the pump unit, the control block with monitoring means is preferably associated with the drive unit which is non-disposable. 
     Thus, indirect means are provided for controlling or monitoring the level of negative pressure applied to the wound, without making any direct connection to a vacuum sensor, transducer or gage to any portion of the system, which has the negative pressure applied to it. The indirect negative pressure monitoring and control result from the need to dispose of any portion of the system, which may come in contact with the pumped media, which is likely to be contaminated or infectious. Accordingly, all the disposable components in the system may be relatively low in cost, to promote discarding them after use. Pressure transducers, vacuum gages or sensors, are relatively costly, and thus not considered disposable. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to understand the invention and to see how it may be applied, a preferred embodiment will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which: 
         FIG. 1  is a schematic sectional view of the vacuum system of the present invention applied on a wound. 
         FIG. 2  shows the disposable portion of the system of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     The present invention provides a system and a method of treating and healing of a body wound, by applying a negative pressure to the wound, over an area sufficient to promote migration of epithelial and subcutaneous tissue toward the wound. 
     It is appreciated that the detailed description that follows is intended only to illustrate certain preferred embodiments of the present invention. It is in no way intended to limit the scope of the invention, as set out in the claims. 
     With reference to  FIG. 1 , in accordance with the present invention, a vacuum system  10  for draining an open wound from liquids exuded therefrom comprises a wound enclosure  12 , a vacuum pump  14 , and waste collection bag  31 . The wound enclosure  12  is connected by a suction tube  16  to an inlet  11  of the vacuum pump. The waste collection bag  31  is connected to an outlet  22  of the vacuum pump. Thereby, when the vacuum pump  14  is operated, the drained liquids flow through the pump into the waste bag  31 . 
     Suction tube  16  is connected to nipple  38  of the enclosure  12  which covers wound area of the body  34  such that suction of air through tube  16  creates negative pressure in the volume above the wound area of the body  34 . A bleeding orifice  35  is provided within the enclosure  12 , or adjacent to it as a tube orifice  37  (i.e. venting arrangement), allowing ambient air to flow into and through suction tube  16 , rendering enclosure  12  non-air tight, or vented. This feature, unlike conventional sealed closures, provides for quick movement of exudate entering suction tube  16 , toward the vacuum pump  14 , and into the waste bag  31 , before it dries up or coagulates and occludes the tube. This feature also provides for introduction of ambient pressure to the wound area of the body  34  whenever the vacuum pump stops pumping, allowing cyclic negative pressure application to the wound, by cycling the vacuum pump on and off alternately. 
     Instead of the bleeding orifice  35  in the enclosure, other flow restrictors may be used to provide for controlled flow of ambient air into the enclosure or into the outlet. For instance, a hole plugged with open cell foam or an open pore sintered metal plug, which restrict the flow, but are not susceptible to plugging as is a small orifice. 
     The vacuum pump  14  comprises a pump unit  18  and a drive unit  40  which are detachably attachable to each other, as explained below. The pump unit  18  includes a two-chambered housing  17  and a diaphragm  24  secured to the underside of the two-chambered housing  17  so as to form a working chamber  29 . 
     The two-chambered housing  17  has a first chamber  13  with the inlet  11  and a second chamber  21  with an outlet  22 . The suction tube  16  is connected to the inlet  11 . Two one-way valves  19  and  20  are present at the bottom of the first chamber  13  and the second chamber  21 , respectively. To the bottom of the two-chambered housing  17  there is attached a mounting base  23 , used to mount the housing  17  to the drive unit  40  by means of a bayonet lock. 
     The diaphragm  24  has an integral rod-shaped drive member  25 , which is used for engagement with the drive unit  40 . 
     The drive unit  40  includes an electric motor  39 , batteries  41  and a control block  50  described below. The shaft of the motor  39  has a crank  27  coupled to a reciprocating rod  26 . The rod  26  has a receptacle with a cavity adapted to receive and lock therein the drive member  25 . 
     When the pump unit  18  is attached to the drive unit  40  by means of the bayonet lock in the base  23 , the drive member  25  is received in the receptacle cavity of the reciprocating rod  26  and then locked therein. 
     Upon activation of the motor  39 , the crank  27  is rotated and reciprocates the receptacle rod  26 , causing the diaphragm  24  to expand and contract the working chamber  29 . Thus the pump unit  18  pumps air or liquid that passes through the one-way valves  19  and  20 . 
     Air and liquids enter the two-chambered housing  17  through the inlet  11  and suction tube  16  which is connected to the patient&#39;s wound enclosure  12 , for the removal of exudate. Liquids and air enter the first chamber  13 , which is under negative pressure when diaphragm  24  reciprocates, driving them past one-way valve  20 , into the second chamber  21 . The air and liquid which are pumped through outlet  22 , enter waste bag  31 . 
     The pump&#39;s ability to pump air and liquid, unlike conventional pumps, which are efficient in pumping only one type of matter, is enhanced by the flexibility of the diaphragm  24  which allows the diaphragm to yield when encountering heavy loads, such as those present when pumping liquid. This diaphragm flexibility also provides an additional substantial advantage: when the negative pressure in working chamber  29  is high, the diaphragm  24  stretches to allow the reciprocation of the receptacle rod  26  to occur, at minimal burden to the electric motor  39 . 
     The waste bag  31  has a vent  15 , through which air and gas are discharged to the atmosphere. Accordingly, waste bag  31  will retain only the waste fluids which are pumped into it. The waste bag may contain a porous media  47  adapted to soak up the drained liquids. 
     It is important to note that waste bag  31  is made of thin plastic sheet, which allow it to be folded or collapsed when not full, providing the convenience of having minimal bulk and minimal inconvenience to the patient using or carrying it. 
     The drive unit  40  also includes a control block  50  with control circuits such as cycle control  42 , which turns the motor pump on and off alternately, motor voltage and current monitoring and control  43 , which controls the negative pressure level produced by the pump unit  18 , by controlling the voltage and current which drive motor  39 . At any given voltage which drives motor  39 , the current draw of the motor is directly related to the negative pressure generated by the pump  18 . Accordingly, monitoring of the current which the motor  39  draws allows for indirect monitoring of the negative pressure attained by pump  18 . The ability to monitor the negative pressure developed by pump  18 , indirectly, precludes the need of making an infectious negative pressure line connection to a pressure transducer or vacuum gage. 
     For example, if the motor  39  is a direct current electric motor, a sensor may sense the electric current driving the motor. Since the direct current motor output torque is directly related to the current driving the motor, and since the motor output torque is directly related to the negative pressure the pump  18  produces, monitoring the motor current or controlling it, provide for monitoring and controlling the negative pressure produced by the vacuum pump. Motor current monitoring is only one of the available methods of indirect negative pressure monitoring and controlling. The same function of negative pressure control may be accomplished by an adjustable torque limiting clutch placed between the motor output shaft and the crank  27 . 
     The control block  50  also has a negative pressure comparator  44 , which compares the desired set negative pressure level obtained by pump  18 , and the actual monitored negative pressure level as obtained indirectly from motor voltage and current monitoring and control  43 . Comparator  44  will activate audible alarm  45 , whenever pump  18  fails to reach the desired pre-set negative pressure level. 
       FIG. 2  shows the disposable portion of the system as an assembly  60 , which includes the pump unit  18 , the waste bag  31 , the connecting tube  16  and the wound enclosure  12 , all separated from the drive unit and from the wound area of the body  34 . The assembly  60  may be disposed of in its totality after use, and replaced by a new assembly, thus keeping the costly drive unit  40  free from any contamination. It would be obvious to those skilled in the art, that the present invention alleviates the need for cleaning or disinfecting any portion of drive unit  40  after use, or providing protective means, such as filters, to keep contaminants from reaching the costly drive  40 .