WO1994021312A2

WO1994021312A2 - Portable medical vacuum aspiration device

Info

Publication number: WO1994021312A2
Application number: PCT/US1994/002495
Authority: WO
Inventors: Thomas F. Fangrow, Jr.; Samuel C. Lim
Original assignee: Life Support Products, Inc.
Priority date: 1993-03-23
Filing date: 1994-03-09
Publication date: 1994-09-29
Also published as: WO1994021312A3

Abstract

A portable, battery-powered aspirator for use in emergency situations having an improved fluid container incorporating a recess for coiling an aspiration hose within the structural outline of the aspirator housing. A connection grommet in the housing between the container and a vacuum pump in the housing includes a stepped throughbore to alternately mate directly with a tube from the container or a different size fitting of an intermediate filter. A removable baffle in an outlet port from the pump reduces noise and vapor discharge. The pump generates a high vacuum pressure and runs efficiently to extend the usable life of the aspirator. An improved recharging unit releasably retains the aspirator on a shelf by simply sliding the aspirator straight back on guide rails. Flexible recharging terminals in the unit automatically align with angle power prongs extending from the rear of the aspirator.

Description

PORTABLE MEDICAL VACUUM DEVICE

Field of the Invention The present invention relates to a portable aspirator, and in particular to an aspirator having a suction pump and a container for storing collected fluid.

Background of the Invention In recent years, portable aspirators have gained popularity in part to increased awareness of the need for sanitary aspiration devices to avoid the spread of disease. These aspirators are often used by fire fighters, paramedics, and other rescue and health workers. Desirable characteristics for a portable aspirator are that it be lightweight and easy to carry, easily operated, simply deployed and packed up again and preferably easy to clean. Such aspirators must also be shock-proof, especially when used by fire fighters and paramedics where it is likely to be continually jostled. It is also desirable that the container in which fluid from the patient is collected be quickly and easily replaceable, so that multiple patients can be handled in rapid succession. Since the portable aspirators must run on batteries, a high efficiency pump is preferable in order to lengthen the battery life between charges.

Additionally, given the emergency situations under which these aspirators are used, the simpler the battery recharging system the better. Typical charging systems utilize a separate transformer box with a cord extending to a source of power and another to the aspirator battery terminals . These prior systems present entanglement as well as storage problems. Furthermore, it is preferred that the aspirator and charging unit be conveniently stored out of the way while charging.

An example of a portable aspirator is shown in U.S. Patent No. 5,134,994 issued to Say. As can be seen from the drawings, however, the aspirator includes tubes which are attached to the exterior of the bag and present an entanglement hazard for fire fighters or paramedics running through buildings. In Design Patent No. 305,798, also issued to Say, a portable medical suction unit having a tube storage flap is shown. The unit, however, does not have an easily visible and replaceable container for receiving bodily fluids. Due to the aforementioned and other drawbacks, there has been a need for a compact, lightweight aspirator having attributes which simplify the operation of the aspirator and also provide a longer life between battery charges.

Summary of the Invention The present invention provides an improved portable aspirator for the suction of fluids, such as vomit, blood or the like, from a choking victim or other patient requiring aspiration. The aspirator generally comprises a rigid housing made portable by a pivoting handle and having several recesses and indicators for the various operating components. The rectangular-shaped housing is mounted on a base plate and has front and rear walls, two side walls and a top wall. The top wall is angled or contoured slightly downward at the front end to facilitate visibility of the components mounted thereon. The housing includes a large, generally rectangular compartment tapering downward into proximity with the base which is open to the top and front walls. A container for storing the aspirated fluids fits within the large compartment and lies flush with the top wall of the housing. The container comprises a cover removably attached to a lower reservoir of transparent construction for viewing the contents through the front wall . An aspiration hose extends from a cover of the container to a patient, while a vacuum hose extends from the cover to a vacuum pump mounted within the housing. The pump generates a reduced pressure within the container, enabling fluid to be suctioned from the patient and stored within the container. The container is monitored through the window and easily removed from the compartment when full .

In one aspect of the present invention, the cover of the container includes a recess for coiling the aspiration tube to lie below the top wall of the aspirator housing. The aspiration tube connects to a nozzle in the top of the cover and may extend up to six feet . A wide peripheral rim around the top of the cover surrounds a central axially depressed recess within which the aspiration tube may be coiled around a central boss. When coiled within the recess, the aspiration hose is confined therein and thus does not pose an entanglement threat when carrying the aspirator.

In another aspect of the present invention, a filter is connected between the vacuum hose and a connector grommet removably mounted in an access hole in the housing. A short length of tubing communicates the grommet with an inlet of the vacuum pump so that reduced pressure generated by the pump is transmitted through a central throughbore of the grommet, the filter and vacuum hose and thereafter into the container. A step diameter of the grommet throughbore allows for the connection of the filter or the vacuum tube directly when a filter is not available when, for instance, the filter is clogged or unavailable or when flushing the aspirator. The throughbore includes an outer large diameter segment which is reduced by a shoulder to an inner smaller diameter segment. An axially extending fitting from the filter snugly mates within the inner small diameter segment, while the vacuum hose snugly mates within the outer large diameter segment . With the filter installed, the vacuum hose attaches over a second axially extending fitting of the filter. The aspirator incorporates a high vacuum-generating, high volume flow rate pump. The pump generally comprises an outer rigid casing defining an inner cylinder within which a piston element reciprocates. One end of the piston element is journalled to an eccentric wheel driven by an electric motor outside the pump casing. The opposite end of the piston element includes an enlarged hollow piston head around which a skirt-like diaphragm is sealingly attached, the diaphragm also sealingly attaching to a groove in the cylinder wall . The region from the piston head and diaphragm to an end face of the cylinder defines a vacuum-generating chamber. Two one¬ way valves are disposed in ports in the end face of the cylinder. An inlet valve communications with the short length of tubing extending to the aforementioned grommet, while an outlet valve communicates with the exterior of the housing.

The pump of the present invention has a high compression ratio due to the relatively small vacuum-generating chamber formed with the piston element in a neutral position proximate the end face. Upon retraction of the piston element from the end face on an induction stroke, a reduced pressure is generated within the chamber which pulls air in through the first one-way valve and eventually creates a vacuum within the container. Upon a exhaust stroke of the piston element, with the piston head advancing toward the end face, the suctioned air is ported out the second one-way valve to the atmosphere. The high compression ratio of the pump, which generates an extremely reduced pressure in the chamber, effectively pulls the piston head back towards the end face on the exhaust stroke, thus reducing input work done by the motor.

An aperture in the housing includes a baffle to contain excessive noise from the motor and pump and also to capture residual vapor from the aspirated fluid. The baffle is removably held in a baffle grommet having an outer flange positioned substantially flush with the aperture in the housing. A short length of tubing connects the inner end of the baffle grommet with the outlet port in the pump end face. The baffle may be removed to easily flush the system from the vacuum hose through the pump and exhaust ports. The filter is removed and the water injected into either the connector grommet throughbore or attached vacuum hose to flush through the connecting tubes, the vacuum-generating chamber and exhaust ports . In a still further feature of the present invention, an improved battery charging configuration is disclosed. The aspirator incorporates a primary rechargeable battery permanently mounted within the housing and also a generally rectangular shaped auxiliary rechargeable battery removably positioned in a similarly shaped recess in the rear wall of the housing. The auxiliary battery is of a conventional type having angled female receptacles shaped to receive power prongs or contacts from the unit being energized. Accordingly, the aspirator includes similarly angled power prongs extending from an internal wall of the rear cavity. A recharging device for the aspirator also has female receptacles for attaching to the extending power prongs and a third contact to signal the aspirator that it is being charged. The present recharging device allows for the aspirator to be pushed directly rearward onto a recharging bracket with the recharging connections in the rear automatically coming into contact without any further manipulation.

The generally L-shaped recharging bracket is mounted to a fixed wall, such as the wall of an emergency vehicle, with a recharging block protruding slightly from a rear vertical portion. Rails on a horizontal shelf portion mate with elongated cut-outs in the bottom of the base plate of the aspirator providing a guide for sliding the aspirator directly towards the vertical portion of the bracket. The recharging block fits within the rear cavity of the aspirator to make the appropriate electrical connections while a locking tab extends around the front edge of the base to retain the aspirator on the bracket. The female receptacles are held facing directly out from the recharging block in a resilient cushion member housed in a small recess. The initial position of the recharging receptacles aligns with the tips of the power prongs from the aspirator. Pushing the aspirator towards the vertical rear wall, and thus the power prongs into the receptacles, causes the receptacles to pivot within the cushioned material and align with the angle of the power prongs due to a flexible electrical coupling with the recharging block. Thus, the rails guide the aspirator onto the recharging bracket while the particular configuration of the receptacles and surrounding cushion allow the contact to be made without any further manipulation. An -shaped locking arm includes the locking tab on the front end and an ejection bar parallel to the vertical rear wall. By pressing down on the locking tab, the rigid locking arm levers the aspirator outward from the supporting wall, accomplishing the unlocking and ejecting steps in one operation.

Brief Description of the Drawings Figure 1 is a perspective view of the portable medical vacuum device of the present invention with an aspiration hose coiled within;

Figure 2 is a view of the vacuum device of Figure 1 showing the aspiration hose extending to a patient; Figure 3 is an exploded perspective view of the vacuum device of Figure 1;

Figure 4 is a cross-sectional view taken along line 4-4 of Figure 1 showing a container and retaining cap with the aspiration hose coiled within; Figure 5 is a partial cross-sectional view taken along line 5-5 of Figure 3 showing an improved filter connection;

Figure 6 is a cross-sectional view of the filter connection of Figure 5 with a flexible hose directly attached; Figure 7 is a schematic view of the vacuum system of the present invention;

Figure 8 is a top plan view of the vacuum device of the present invention;

Figure 9 is a partially cut-away front elevational view of the vacuum device; Figure 10 is a cross-sectional view of a pump of the present invention with a piston in the mutual position taken along line 10-10 of Figure 9;

Figure 11 is a cross-sectional view of the pump with the piston partially retracted; Figure 12 is a cross-sectional view of the pump with the piston fully retracted;

Figure 13 is a rear elevational view of the vacuum device of the present invention showing a rear cavity and power prongs for a battery or recharging device; Figure 13a is a view taken along line 13a-13a of the power prongs shown in Figure 13 ;

Figure 14 is a bottom plan view of the vacuum device of the present invention;

Figure 15 is a perspective view of a preferred battery recharger and mounting bracket of the present invention. Description of the Preferred Embodiments A portable medical vacuum device or aspirator 20 of the present invention is shown in Figure 1. The aspirator generally comprises an irregular-shaped case or housing 22 including apertures and recesses for seating several removable components and control element and providing a cosmetic cover for internal battery, motor and pump elements, which will be described in detail below. The housing 22 is generally defined by a top wall 25, a front wall 27, a rear wall 29

(Figure 13) and two side walls 30a, 30b, and attaches over a bottom plate 26. The material of the housing 22 is lightweight, stiff and preferably durable, such as polypropylene or the like, and is preferably molded to the curvilinear contours shown in the drawings. The entire unit is approximately 12 to 16 inches wide, 4 to 6 inches deep and 10 inches tall, and preferably weighs under 10 pounds for portability. A pivoting handle 24 mounts to an internal load- bearing frame 28 (Figure 9) through bolt-holes in the housing and preferably cooperates with detents (not shown) on the side of the housing to enable positioning at convenient angles.

As seen in the frontal perspective view of Figures 1 and 2, the left half of the housing 22 incorporates a deep cavity or compartment 32 for holding a container 34 used to collect aspirated fluids. The right half of the housing 22 includes a face plate 36 through which a number of battery status indicators 38 and a control knob 40 protrude. The right side of the housing 22 also contains a vacuum pressure gauge 42, visible through an aperture 44, and a second smaller cavity 46 for a bottle of wash water 48 used for cleaning a patient nozzle 57.

With additional reference to Figure 3 , the aspirated fluid container includes a lower reservoir 50 and an upper lid or cover 52. The container cover 52 is releasably attached to the reservoir 50 for emptying and cleaning. The cover 52 includes several hose nozzles 54 to which flexible tubing attaches; more particularly, an aspiration hose 56 extends to a patient, as shown in Figure 2, and a vacuum hose 58 communicates with the vacuum pump. The pump generates a reduced pressure within the container 34 which is then transmitted through the aspiration hose 56 to the suction nozzle 57 in a patient's mouth. A choking victim, or other emergency patient, may have vomit or other fluids blocking air flow in the esophagus which must be removed quickly to prevent unconsciousness and even death from occurring.

The large compartment 32 in the left side of the housing 22 is preferably open to the front wall 27 in order to view the container 34 within. Typically, the container reservoir 50 is transparent to monitor the volume of aspirated fluid within. When the volume exceeds a certain level, a replacement container is installed in the aspirator.

As shown best in Figure 3, the aspirator container 34 of the present invention includes a separate cover shield portion 60 bonded onto the cover 52 under which the aspiration hose 56 may be coiled. The shield 60 generally comprises an irregular shaped body with a large cover access aperture 61. A wide overhang 62 in combination with an inner, substantially vertical wall 64 define an annular recess 66 above the cover 52 around the generally centered hose nozzles and optional connections 54.

As seen in Figure 4, the annular recess 66 is deep enough to coil the aspiration hose 56 several times around the nozzles and connections 54 so that the hose lies within the shield 60 below the top wall of the aspirator housing 22. Preferably, the shield 60 itself is flush with the top wall 25 of the housing 22 when the container 34 is inserted fully into the large compartment 32.

Now referring to Figures 7 and 9-12, the pump 76 includes an outer rigid casing 78 and cap 100 defining a hollow cylinder 80 within which a piston-like element 82 reciprocates. The piston element 82 comprises a linkage arm 84 having a hollow piston head 86 on one end and a journal member 88 on the opposite end which pivots on a rotating stub- shaft extension 90 of an eccentric wheel 92. The eccentric wheel 92 is directly rotated by a shaft 94 of an electric motor 96 or, alternatively, via reduction gears (not shown) . The stub-shaft extension 90 rotates with the wheel 92 causing the piston element 82 to translate in and out of the cylinder 80. The piston head 86 has a smaller diameter than the cylinder diameter to ensure a minimum amount of clearance therebetween, as the lateral movement of the journal member 88 around the eccentric wheel 92 causes the head to tilt as well as slide in and out.

An inner lip 101 of an elastomeric rolling diaphragm 98 mounts to a groove 99 in the piston head 86 while an outer rim 97 mounts between the casing 78 and cap 100 to provide an air- tight seal across the clearance between the piston and cylinder. The inner lip 101 thus translates in and out with the head due to the slack provided by a central rollover portion 103 in the clearance space. A vacuum-generating chamber 102 is thus formed in the region of the cylinder 80 between the joint piston head 86 and diaphragm 98 and an end face 104. Two one-way valves 106,110 mounted in through-holes in the end face 104 of the vacuum-generating chamber 102 communicate with the exterior of the pump casing 78. A one¬ way intake valve 106 attaches to a short length of vacuum tube 108 which eventually communicates with the aspiration container 34. An exhaust check valve 110 allows air to escape from the chamber 102 but prevents air from coming in.

From a neutral position, shown in Figure 10, the piston element 82 retreats on an induction stroke from the end face 104 of the vacuum-generating chamber 102, seen in Figure 11, creating a negative pressure within the chamber. On an exhaust stroke of the piston element 82, air is forced out through the exhaust valve 110 to ready the pump 76 for another cycle of vacuum generation. The vacuum generated within the chamber 102 creates a reduced pressure within the short length of tubing 108, a connection grommet 112, a filter 114, the vacuum hose 58 and the container 34. Air is then pulled through the one-way intake valve 106 from the container 34 and, after a short period of container evacuation, through the aspiration hose 56 and patient nozzle. Repeated cycles of the piston element 82 movement rapidly generates and maintains a desired reduced pressure in the aspiration container 34.

Referring to the schematic view of Figure 7, the vacuum generated within the container 34 may be adjusted by turning the control knob 40. The control knob 40 regulates an atmospheric air inlet valve 182 communicating with the first tubular section 108. Opening the control valve 182 wider allows more fresh air into the first tubular section 108, thus decreasing the volume of air pulled through the container 34. Low vacuum pressures are necessary for aspirating small children or infants .

With reference to Figures 5 and 6, the improved connecting grommet 112 comprises an elastomeric member having a tubular shaft 116 with an outwardly extending flange 118 on one end. The tubular shaft 116 has an exterior dimension sized to fit within an access hole 120 in an interior wall 122 (Figure 3) of the large compartment 32. The flange 118 provides a stop, preventing the grommet 112 from falling through the access hole 120. A small ridge 123 axially spaced along the tubular shaft 116 from the flange 118 contacts the inner edge of the access hole 120 to nominally retain the grommet 112 within the hole. A throughbore 124 extends the length of the grommet 112 and communicates between the first tubular section 108 from the vacuum pump and the filter member 114 on the container side. The filter 114 includes a central generally disk-shaped body 126, containing a conventional filter element, and two oppositely directed axial fittings 128a, 128b; one fitting 128a for insertion past a central aperture 130 in the flange 118 into the grommet throughbore 124 and the other fitting 128b for insertion in the end of the vacuum hose 58 going to the cover 52 of the container. The fittings 128 on the filter member 114 are equivalently sized to reversibly fit within both the vacuum hose 58 and a small diameter channel section 134 of the connection member.

As shown in Figure 5, the connection member throughbore 124 includes a diameter reduction step wherein an outer large diameter section 132 transitions to the inner smaller diameter section 134 sized to receive one of the filter fittings 128. Advantageously, the outer large diameter section 132 is sized to snugly fit around the vacuum hose 58, which is normally connected over the opposite filter fitting. In the case of a blocked or unavailable filter member 114, or when flushing the aspirator 20, the vacuum hose 58 may be attached directly to the grommet 112, as in Figure 6. The throughbore 124 on the tubular shaft 116 end also includes a stepped diameter bore so as to be large enough at the outer end to snugly fit around the first vacuum tube section 108, having the same inner diameter as the vacuum hose 58.

Now looking at Figures 3 and 8, the exhaust valve 110 in the cylinder casing 78 communicates with a grommet 140 in an aperture in the aspirator housing 22 via a short length of tube 145, the grommet having a baffle 142 attached thereover. The baffle grommet 140 includes a flange 141 lying substantially flush with an indented face of a recess 143 in the right side wall 30b. The baffle 142 fits within the recess 143 and limits the noise output from the pump 76 and motor 96 through the port 140. Additionally, the baffle 142 catches some of the residual vapor from the aspirated fluid.

The baffle 142 is removed in order to flush the aspirator 20 between uses. In order to flush the aspirator

20, the container 34 is disconnected from the vacuum hose 58 and water introduced into the hose or grommet 112 with the pump 76 preferably turned off. Water thus flushes through the vacuum hose 58, grommet 112, first section of tube 108, one-way intake valve 106, vacuum-generating chamber 102 and exhaust valve 110 to exit out the baffle grommet 141 in the exhaust port 140, exterior of the housing 22. In order to efficiently power the pump 76 of the present invention, a motor 96 (Figures 7 and 9) having relatively low consumption is provided. In one embodiment, the motor 96 has a 45 watt power requirement (12 volts and 3.5 amps) and produces an output of l/20th hp. There is a primary rechargeable battery 148 permanently mounted to the internal frame 28 of the aspirator, and an auxiliary rechargeable battery (not shown) detachably positioned in a rear housing cavity 152 (Figure 13) . Switching electronics allow the motor 96 to draw power from whichever battery has a higher voltage.

The arrangement of the battery 148, motor 96 and pump 76 within the housing 22 is schematically shown in the cutaway of Figure 9. The internal components are all mounted to an internal frame 28 which in turn is mounted on the bottom plate 26. An important feature of the present invention is the compact assembly resulting in a more portable and easier to store unit. In order to reduce the bulk of internal components, the sideways lying pump 76 has an improved efficiency requiring a smaller motor 96 and associated primary battery 148. The auxiliary battery fits in the rear cavity 152 which doubles as a receiving dock for a recharging unit or block 167 (Figure 15) , further saving space. Additionally, the container 34 conforms to the tilted compartment 32, as seen in Figure 4, leaving room rearward of the compartment in the housing 22 for this rear cavity 152. In short, the various attributes of the present aspirator 20 combine to reduce the overall space requirements resulting in a maximum depth from front to rear of six inches facilitating placement on an improved battery recharger/storage shelf, as will be described below with reference to Figure 15.

The auxiliary battery may be removed and the pump 76 run on only the primary battery 148, or the auxiliary battery may be fully charged to effectively double the useful life of the aspirator. Preferably, the auxiliary battery is a standard model manufactured by Physio-Control . The auxiliary battery includes two angled female receptacles adapted to fit onto two electrical power prongs 154, seen in Figure 13a, extending at a slight angle from an interior wall 156 of the rear cavity. The prongs 154 also provide an attachment for a recharging device 158 for the main battery 148, as will be described below.

In a preferred embodiment as seen in Figure 15, a recharging device 158 for the main battery 148 also functions as a storage unit . The storage unit generally comprises an L-shaped bracket 160 having a vertical rear wall 162, a horizontal aspirator support shelf 164 and a pair of side gussets 165 for support. Mounting holes 157 in the rear wall 162 enable the device to be attached to a fixed surface with bolts or other similar expedient. A front lip 159 provides a mount for a power switch 161 and a pair of fuse access covers 163.

The support shelf 164 includes guide rails 166 sized and shaped to fit within elongated slots 168 on the bottom of the base plate 26, as shown in Figure 14. The aspirator 20 is thus slid backward toward the rear wall 162 on the rails 166 in order for the power prongs 154 to come into proximity with a pair of electrical terminals 169 mounted in the recharging circuitry block 167. A power cord 177 extends out the rear of the device 158 from the block 167. The block 167 is sized to fit within the aspirator rear cavity 152. Preferably, the terminals 169 comprise cylindrical receptacles having outer chamfers facilitating entry of the prongs 154, the receptacles sized to snugly receive the prongs.

The electrical terminals 169 automatically orient to the slightly angled prongs 154 when the aspirator 20 is pushed rearward on the shelf 164. In this regard, the terminals 169 are flexibly coupled at the rear to the recharging electronic circuit in the block 167 and are held in resilient cushioning sleeves 175. The sleeves 175 allow the terminals 169 to pivot a slight angle in order to re-orient to the angle of the power prongs 154. Initially, the mouth of the terminals 169 are aligned with the tips of the power prongs 154. As the aspirator 20 is slid rearward on the rails 166, the terminals 169 easily conform to the attitude of the power prongs 154, and are returned to their original orientation upon removal of the aspirator.

With reference to both Figures 14 and 15, a recharge signaling plug 171 is provided which attaches to a receiving outlet 170 on the rear side of the aspirator 20. When connected, this plug 171 signals the circuitry of the aspirator that it is in a charging mode. Thus, when the auxiliary battery, remotely charged, is installed in the rear cavity 152, the aspirator 20 will not inadvertently assume that it is being charged, due to the absence of this signaling plug-to-outlet connection.

The recharging bracket 160 incorporates a locking and releasing feature enabling the aspirator 20 to be retained safely on a wall of a moving vehicle, for example, yet be quickly detached for use. An L-shaped locking arm 172 pivots about the bracket at a corner point 174 proximate the rear wall 162. The arm 172 extends both horizontally forward from the corner 174 to a lock tab 178 at the front edge of the support shelf 164 and upward, forming an ejection bar 176. In a relaxed position, with the aspirator 20 removed, the horizontal leg of the locking arm 172 falls into a channel 180 of the shelf 164 due to the raised position of the corner pivot 174 above the channel 180 and thus the ejection bar 176 angles forward slightly. As the aspirator 20 is pushed onto the shelf 164, the rear wall 29 forces the ejection bar 176 upright causing the locking tab 178 to releasably catch the front edge of the base 26 to retain the aspirator 20 horizontally on the shelf 164. A downward pressure disengages the locking tab 178 from the base 26, while at the same time, the ejection bar 176 is levered to urge the aspirator 20 slightly forward on the rails 166, thus separating the prongs 154 from the battery charger terminals 169. The combined unlatching and disengagement from the battery charging terminals 169 is accomplished in one operation. In the preferred embodiment, there is a minimum "warm- up" time necessary after the pump 76 has been turned on before the container possesses a reduced pressure sufficient to begin aspirating the patient. Preferably, there is no more than a 10-second delay after turning the pump 76 on before a vacuum equivalent to 25 inches of Hg is formed in a container having a capacity of 1200 cc. Furthermore, the improved pump 76 of the present invention provides a high vacuum as well as a high flow rate. In one embodiment, the pump 76 produces a flow rate of 30 liters/min with the filter 114 and the baffle 142 installed. A flow rate of 40 liters/min may be attained by removing the filter 114 and baffle 142 for extreme situations or when flushing.

The present aspirator 20 simultaneously provides a high vacuum pump 76 with a longer battery life between recharges . To provide for a high vacuum, the hollow head portion 86, comprising an annular wall 146 enclosed by an end cap 144, is positioned extremely close to the end face 104 of the vacuum- generating chamber 102 in a neutral position, as shown in Figure 10. Advantageously, the intake valve 106 is recessed in a depression 107 in the end face 104 to allow the end cap 144 to nearly meet the end face. Thus, when the piston element 82 is retracted (Figures 11-12) , generating the vacuum as described previously, the vacuum will be particularly strong due to the volumetric, or compression, ratio between the evacuated chamber 102 as shown in Figure 12, and that of the initial position shown in Figure 10. The components of the pump casing 78 and piston element 82 are preferably constructed of a lightweight high-strength material, such as polycarbonate and the hollow construction of the piston head 86 further reduces the mass and associated power needed to linearly actuate the piston via the eccentric wheel 92. Moreover, while power is required from the motor 96 during the induction stroke, such a high vacuum is formed in the chamber 102 that relatively little extra work is necessary to drive the piston element 82 back on the exhaust stroke reducing power consumption and further extending the usable life of the aspirator 20 between battery charges.

The rolling diaphragm 98 also assists in increasing the compression ratio. Normally, as in Figure 10, the diaphragm 98 is folded alongside the piston head 82 so as to reduce the volume in the vacuum chamber 102 in the neutral position of the piston element. The installed position of the rollover portion 103 toward the end face 104 eliminates some of the volume of the necessary clearance space. Although this invention has been described in terms of certain preferred embodiments, other embodiments that are apparent to those of ordinary skill in the art are also within the scope of this invention.

Claims

CLAIMS :

1. A portable aspirator comprising: a housing, a compartment in said housing open to an upper wall of said housing; a suction pump within said housing; a container removably positioned in said compartment and interconnected to said suction pump so that a reduced pressure is created in said container, said container including a cover accessible through the opening in the upper wall of the housing; flexible tubing connected to the interior of the container through said cover; and structure on said cover for storing said tubing.

2. The aspirator of Claim 1, wherein said cover structure is formed to facilitate the coiling of said tubing when being stored.

3. The aspirator of Claim 1, wherein said cover structure includes a generally annular recess surrounding a central portion of said cover and fitting within an interior peripheral portion of said cover.

4. The aspirator of Claim 1, wherein said cover structure includes a shield attached to the top of said cover, said shield having an outer peripheral wall and an upper rim extending radially inwardly from said peripheral wall, said shield defining a central axially recessed portion above said cover to enable said tubing to be coiled and confined within the peripheral wall and upper rim.

5. The aspirator of Claim 4, wherein the upper wall of said shield is substantially flush with the surrounding top wall of said housing, and a front sidewall portion of said shield is substantially flush with a front side wall of said housing.

6. The aspirator of Claim 1, wherein said housing has a sidewall with an opening therein that opens to said container compartment, thereby making the side of the container visible from the exterior of the housing, said container including a sidewall portion which is transparent so that the level of the contents in the container may be observed without removing the container from the housing.

7. The aspirator of Claim 1, including a removable filter positioned in a tube connecting said cover to said pump, said removable filter including an outer casing having a fitting on opposite ends for connecting to said tube and to said pump, one end of said tube being slidably positioned on one of said filter fittings, and the other of said filter fittings being positioned within a connection grommet leading to said pump, the interior of said grommet including a section adapted to sealingly receive said tube so that when the filter is not being used, the tube may be directly connected to said grommet.

8. The aspirator of Claim 1, wherein said pump includes a pump casing having a pump cylinder formed therein, a pump piston which reciprocates within said cylinder, a rolling diaphragm attached to said cylinder and said piston to form a piston chamber in combination with said cylinder, an air intake valve connecting the chamber to a tube leading to said container, an air outlet valve connecting said chamber to an outlet in said pump casing, said pump casing being positioned within said housing such that said outlet opens to a hole in an exterior wall of said housing so that water may be directed through the pump for cleaning.

9. The aspirator of Claim 1, comprising: a base plate on which said housing and said pump are mounted, said housing being a molded shell with a top wall, a front wall, a back wall and left and right side walls enclosing said pump; and one or more guide members on the bottom of said base plate extending approximately parallel to said side walls between said front and back walls .

10. The aspirator of Claim 9, comprising: a rechargeable battery mounted to said base plate; a motor for powering said pump, said motor mounted to said base plate and electrically connected to said battery; a bracket for mounting on a wall adjacent an electrical outlet and sized to receive said aspirator; a recharging unit mounted on said bracket; and said bracket having guide structure adapted to cooperate with said base plate guide members for guiding said aspirator on to said bracket and guiding said unit into electrical connection with said rechargeable battery.

11. An aspirator, comprising: a housing; a container positioned within a compartment in said housing; a suction pump positioned in said housing; a tube connecting said container to said pump so as to produce a reduced pressure in said container; a filter connected to one end of said tube and connected to said pump, the exterior of the end of said tubing which connects to said filter being sized so as to fit directly into a connector leading to said suction pump so that said tube may be directly connected to the suction pump when the filter is not employed.

12. The aspirator of Claim 11 wherein said connector is a grommet positioned in a wall of said housing, said grommet having a small inner diameter portion for snugly receiving an end of said filter, and said grommet having a large inner diameter axially outer portion for snugly receiving the exterior of said tube.

13. An aspirator, comprising: a housing ; a suction pump positioned within said housing, said suction pump including a pump casing having a cylinder formed therein, a piston to reciprocate within said cylinder, a rolling diaphragm secured to said cylinder and said piston to form a chamber with said cylinder for said piston, said pump casing including an inlet and an intake valve for permitting fluid flow into the chamber but preventing fluid flow out of the chamber, said casing further including an outlet and a check valve in said outlet permitting fluid flow out of said chamber but preventing fluid flow into said chamber, said casing outlet being aligned with and adjacent to an outlet in said housing so that said casing inlet may be connected to a water supply so that water is directed through said inlet, said pump chamber and said outlet.

14. An aspirator apparatus comprising: a portable aspirator including a housing having a top wall, a front wall, and a back wall; a compartment in said housing open to said top wall for receiving a container; a pump and a motor in said housing for connection to said container to develop a reduced pressure in the container so that fluids may be sucked into the container by a tube extendable from the container to a patient; a rechargeable battery in said housing and connected to said motor; a recess in said housing back wall for receiving an auxiliary battery; a pair of terminals in said recess leading to said motor for connection to said auxiliary battery; and a recharging unit for connection to a source of power and adapted to fit into said recess and connect to said terminals;

15. The apparatus of Claim 14 including: a bracket for mounting on a wall adjacent an electrical outlet and sized to receive said aspirator, said recharging unit being mounted on said bracket; and said bracket and said aspirator having guide structure for guiding said aspirator on to said bracket and guiding said unit into said recess and into connection with said terminals.

16. The apparatus of Claim 15, wherein said guide structure includes one or more mating ribs and grooves on the bottom of said aspirator and on said bracket.

17. The apparatus of Claim 15, wherein said bracket includes a horizontal shelf and a vertical wall, and said rib structure includes a pair of spaced ribs extending upwardly from the shelf and extending generally perpendicular to said vertical wall, and said guide structure includes a pair of spaced recesses in a bottom wall of said aspirator that slidably fit onto said ribs to guide said aspirator towards said vertical wall.

18. The apparatus of Claim 15, including an arm for locking and releasing said aspirator on said bracket, said arm having a generally L-shape and being pivoted to said bracket near the intersection of a vertical segment and a horizontal segment of said arm, said horizontal segment extending generally from a vertical wall of said bracket towards the forward edge of a horizontal shelf of said bracket, said horizontal arm segment having an upwardly extending latch on its forward end, said latch being in the path of said aspirator as the aspirator is slid onto the bracket so that the arm is pivoted into release position by said aspirator, said aspirator and said arm being dimensioned such that as the aspirator engages the vertical segment of said locking arm, the arm is pivoted by the aspirator into a latching position wherein said latch engages the lower portion of said aspirator to latch the aspirator in position on said bracket, said arm being pivotable into release position by depressing said latch causing the arm vertical segment to push the aspirator forwardly so as to release the aspirator, while simultaneously withdrawing said terminals from said recharging unit .

19. The apparatus of Claim 15, wherein said terminals extend generally rearwardly from said back wall but are angled slightly from a direction perpendicular to said back wall so as to mate with terminals on the auxiliary battery to be mounted on the recess, said recharging unit having a pair of terminals adapted to mate with the terminals extending from said back wall, said recharging unit terminals being resiliently mounted so that the terminals of the aspirator and the terminals of the recharging unit can fit together and the terminals on the recharging unit align with the terminals on the aspirator while the aspirator is moved on said bracket in said direction.

20. An aspirator, comprising: a housing; a container positioned in a recess in said housing for receiving aspirated fluids; a rechargeable battery positioned within said housing; a motor positioned within said housing and electrically connected to said battery; a high efficiency suction pump positioned within said housing and powered by said motor, the pump efficiency extending the time between battery charges, said suction pump comprising: a pump casing having a cylinder with an end face formed therein; a piston having a hollow piston head on one end and a bearing on the opposite end, said bearing adapted to rotate on an eccentric wheel to cause said piston to reciprocate within said cylinder, said piston head being sized slightly smaller than said cylinder providing an annular clearance around said piston head to allow for lateral movement of said piston head; a rolling diaphragm secured to said cylinder and said piston head to form a chamber with said cylinder between said diaphragm and said end face, said diaphragm having a rollover portion folded alongside said piston head toward said end face in an initial position of said piston closest to said end face, said rollover portion substantially eliminating said clearance volume from a chamber volume in said initial position; said end face including a recessed air intake valve connecting the chamber to a tube leading to said container; and an air outlet valve recessed in said end face connecting said chamber to an outlet in said pump casing, said recessed position of said inlet and outlet valves allowing said piston head to be positioned nearly flush with said end face, further decreasing said chamber volume in said initial position thus increasing a compression ratio of said pump.

21. The aspirator of Claim 20, wherein said motor is a maximum 1/20 horsepower output motor and said container has at least an internal volume of 1200 cc, wherein said pump can create a vacuum of 25 mm Hg in said container.

22. The aspirator of Claim 21, wherein said pump can said vacuum in said container within 10 seconds of turning said motor on.

23. The aspirator of Claim 21, wherein said pump can induce a flow rate of 40 liters of air per minute through said intake valve.