Patent Description:
Laparoscopic or "minimally invasive" surgical techniques are becoming commonplace in the performance of procedures such as cholecystectomies, appendectomies, hernia repair and nephrectomies. Benefits of such procedures include reduced trauma to the patient, reduced opportunity for infection, and decreased recovery time. Such procedures within the abdominal (peritoneal) cavity are typically performed through a device known as a trocar or cannula, which facilitates the introduction of laparoscopic instruments into the abdominal cavity of a patient.

Additionally, such procedures commonly involve filling or "insufflating" the abdominal cavity with a pressurized fluid, such as carbon dioxide, to create an operating space, which is referred to as a pneumoperitoneum. The insufflation can be carried out by a surgical access device, such as a trocar, equipped to deliver insufflation fluid, or by a separate insufflation device, such as an insufflation (veress) needle. Introduction of surgical instruments into the pneumoperitoneum without a substantial loss of insufflation gas is desirable, in order to maintain the pneumoperitoneum.

During typical laparoscopic procedures, a surgeon makes three to four small incisions, usually no larger than about twelve millimeters each, which are typically made with the surgical access devices themselves, often using a separate inserter or obturator placed therein. Following insertion, the obturator is removed, and the trocar allows access for instruments to be inserted into the abdominal cavity. Typical trocars provide a pathway to insufflate the abdominal cavity, so that the surgeon has an open interior space in which to work.

The trocar must also provide a way to maintain the pressure within the cavity by sealing between the trocar and the surgical instrument being used, while still allowing at least a minimum amount of freedom of movement for the surgical instruments. Such instruments can include, for example, scissors, grasping instruments, and occluding instruments, cauterizing units, cameras, light sources and other surgical instruments. Sealing elements or mechanisms are typically provided on trocars to prevent the escape of insufflation gas from the abdominal cavity. These sealing mechanisms often comprise a duckbill-type valve made of a relatively pliable material, to seal around an outer surface of surgical instruments passing through the trocar.

<CIT>, <CIT> and <CIT> describe systems and methods according to the state of the art for controlling a gasflow during laparoscopic surgical procedures.

SurgiQuest, Inc. , a wholly owned subsidiary of ConMed Corporation has developed unique gas sealed surgical access devices that permit ready access to an insufflated surgical cavity without the need for conventional mechanical valve seals, as described, for example, in <CIT> and <CIT>. These devices are constructed from several nested components including an inner tubular body portion and a coaxial outer tubular body portion. The inner tubular body portion defines a central lumen for introducing conventional laparoscopic or endoscopic surgical instruments to the surgical cavity of a patient and the outer tubular body portion defines an annular lumen surrounding the inner tubular body portion for delivering insufflation gas to the surgical cavity of the patient and for facilitating periodic sensing of abdominal pressure.

SurgiQuest has also developed multimodal surgical gas delivery systems for use with the unique gas sealed access devices described above. These gas delivery systems, which are disclosed for example in <CIT> and <CIT> have a first mode of operation for providing gas sealed access to a body cavity, a second mode of operation for performing smoke evacuation from the body cavity, and a third mode of operation for providing insufflation gas to the body cavity.

In the prior art SurgiQuest gas delivery system, the delivery or outflow of insufflation gas to the body cavity is controlled by solenoid valves, which have certain limitations with respect to the ability to control gas flow rates dynamically. For example, a solenoid valve with a <NUM> orifice has two flow states: zero and the <NUM> orifice flow as a function of the differential pressure. However, a <NUM> orifice proportional valve has an infinite number of intermediate flow settings, or equivalent orifice diameters.

Since flow is a function of the square of the orifice diameter, the additional intermediate valve positions of a proportional valve provide fine control beyond a simple linear relationship, as well as the ability to achieve stable flow rates at lower pressure, reduce pressure oscillation and eliminate pneumatic hammer. Furthermore, the first <NUM>% of valve opening, or an effective orifice diameter of <NUM>, modulates one percent (<NUM>%<NUM>) of full-open flow; which could be favorable in pediatric applications.

The present invention provides a manifold assembly for a surgical gas delivery system as defined in claim <NUM>.

The present disclosure is directed to a new and useful manifold assembly for a surgical gas delivery system, which includes a manifold body having an inlet port for receiving gas from an outlet side of a compressor and an outlet port for recirculating gas to an inlet side of the compressor, and a bypass valve communicating with the inlet port and the outlet port of the manifold body, wherein the bypass valve includes an electro-mechanical valve actuator for dynamically controlling the flow of gas through the bypass valve.

The manifold assembly further includes an air ventilation valve that is operatively associated with the inlet side of the compressor, upstream from the bypass valve. The air ventilation valve includes an electro-mechanical valve actuator for dynamically controlling the ingress of air from atmosphere. A smoke evacuation valve is operatively associated with the outlet side of the compressor, upstream from the bypass valve. The smoke evacuation valve includes an electro-mechanical valve actuator for dynamically controlling the egress of gas from the manifold assembly when the gas delivery system is operating in a smoke evacuation mode.

A gas fill valve is operatively associated with the outlet side of the compressor, upstream from the bypass valve. The gas fill valve includes an electro-mechanical valve actuator for dynamically controlling the receipt of gas from a source of surgical gas. The manifold assembly further includes an over pressure relief valve that is operatively associated with the outlet side of the compressor, downstream from the bypass valve, for controlling the release of gas from the manifold assembly. Preferably, the over pressure relief valve is a solenoid valve.

The manifold body includes a delivery port for delivering gas to a gas sealed access port and a reception port for receiving gas from the gas sealed access port. In addition, the manifold body includes a gas quality sensor operatively associated with the outlet side of the compressor, downstream from the bypass valve, for monitoring a level of CO<NUM> in gas recirculating through the manifold assembly. The manifold body also includes a first pressure sensor operatively associated with the inlet side of compressor, downstream from the bypass valve, and a second pressure sensor operatively associated with an outlet side of the compressor, downstream from the bypass valve.

In one embodiment of the present disclosure, each electro-mechanical valve actuator is a motorized linear actuator, which includes a respective rack and pinion mechanism. Each rack and pinion mechanism includes a horizontal actuation shaft, a horizontal drive rack gear operatively associated with the horizontal actuation shaft, a rotatable drive pinion gear driven by the horizontal drive rack, and a vertical driven rack gear driven by the driven pinon gear and operatively associated with a spring-loaded vertical valve stem. Preferably, each horizontal drive rack gear is mounted to translate along a first horizontal axis, and each rotatable driven pinion gear is mounted to rotate about a second horizontal axis that extends perpendicular to the first horizontal axis.

In another embodiment of the present disclosure, each electro-mechanical valve actuator is a motorized rotary actuator, which includes a reduction gear assembly operatively associated with a spring-loaded vertical valve stem. In yet another embodiment of the present disclosure, each electro-mechanical valve actuator is a motorized rotary actuator, which includes an axial drive screw operatively associated with a spring-loaded vertical valve stem.

These and other features of the manifold assembly of the present disclosure will become more readily apparent to those having ordinary skill in the art to which the present disclosure appertains from the detailed description of the preferred embodiments taken in conjunction with the following brief description of the drawings.

So that those skilled in the art will readily understand how to make and use the gas delivery system and method of the present disclosure without undue experimentation, preferred embodiments thereof will be described in detail herein below with reference to the figures wherein:.

Referring now to the drawings wherein like reference numerals identify similar structural elements and features of the present disclosure, there is illustrated in <FIG> a new and useful multi-modal surgical gas delivery system <NUM> that is adapted and configured for gas sealed insufflation, recirculation and smoke evacuation during an endoscopic or laparoscopic surgical procedure. The multi-modal surgical gas delivery system <NUM> includes a gaseous sealing manifold <NUM> for communicating with a gas sealed access port <NUM> and an insufflation manifold <NUM> for communicating with the gas sealed access port <NUM> and with a valve sealed access port <NUM>.

The gas sealed access port <NUM> is of the type disclosed in commonly assigned <CIT>. The gas sealed access port <NUM> is adapted and configured to provide gas sealed instrument access to a body cavity, while maintaining a stable pressure within the body cavity (e.g., a stable pneumoperitoneum in the peritoneal or abdominal cavity). In contrast, the valve sealed access port <NUM> is a conventional or standard trocar, for providing access to a body cavity through a mechanical valve seal, such as, for example, a duckbill seal, septum seal or the like. Depending upon the requirements of a particular surgical procedure, the multi-modal gas delivery system <NUM> can be utilized with either the gas sealed access port <NUM>, the valve sealed access port <NUM> or with both access ports <NUM>, <NUM> at the same time.

The gas delivery system <NUM> further includes a compressor or positive pressure pump <NUM> for recirculating surgical gas through the gas sealed access port <NUM> by way of the gaseous sealing manifold <NUM>. The compressor <NUM> is preferably driven by a brushless DC (direct-current) motor, which can be advantageously controlled to adjust gas pressure and flow rates within the gas delivery system <NUM>, as disclosed for example in commonly assigned <CIT>.

Alternatively, the compressor <NUM> can be driven by an AC motor, but a DC motor will be relatively smaller and lighter, and therefore more advantageous from a manufacturing standpoint.

An intercooler and/or condenser <NUM> is operatively associated with the compressor <NUM> for cooling or otherwise conditioning gas recirculating through the gaseous sealing manifold <NUM>. A UVC irradiator <NUM> is operatively associated with the intercooler or condenser <NUM> for sterilizing gas recirculating through the internal flow passages <NUM> formed therein by way of the compressor <NUM>. In addition, the UVC irradiator <NUM> is intended to sterilize the interior surfaces of the gas conduits or flow passages <NUM> through which the gas flows within the intercooler/condenser <NUM>.

The UVC irradiator preferably includes at least one LED light source or a florescent light source that is adapted and configured to generate UVC radiation at a wavelength of about between <NUM>-<NUM>, and preferably about <NUM>. This ultraviolet light at such a wavelength can sterilize viral, bacterial and microbial bodies within the gas conduits of the system, and can reduce coronavirus including SARS-COV-<NUM>.

Preferably, compressor <NUM>, intercooler/condenser <NUM>, gaseous sealing manifold <NUM> and insufflation manifold <NUM> are all enclosed within a common housing, which includes a graphical user interface and control electronics, as disclosed for example in commonly assigned <CIT>.

The gas delivery system <NUM> further includes a surgical gas source <NUM> that communicates with the gaseous sealing manifold <NUM> and the insufflation manifold <NUM>. The gas source <NUM> can be a local pressure vessel or a remote supply tank associated with a hospital or healthcare facility. Preferably, gas from the surgical gas source <NUM> flows through a high pressure regulator <NUM> and a gas heater <NUM> before it is delivered to the gaseous sealing manifold <NUM> and the insufflation manifold <NUM>. Preferably, the high pressure regulator <NUM> and the gas heater <NUM> are also enclosed with the compressor <NUM>, intercooler <NUM>, gaseous sealing manifold <NUM> and insufflation manifold <NUM> in the common housing.

The gas delivery system <NUM> further includes a first outlet line valve (OLV1) <NUM> that is operatively associated with the insufflation manifold <NUM> for controlling a flow of insufflation gas to the valve sealed access port <NUM> and a second outlet line valve (OLV2) <NUM> that is operatively associated with the insufflation manifold <NUM> for controlling a flow of insufflation gas to the gas sealed access port <NUM>.

In accordance with a preferred embodiment, the first and second outlet line valves <NUM>, <NUM> of insufflation manifold <NUM> are proportional valves that are configured to dynamically alter or otherwise control the outflow of insufflation gas to the access ports <NUM>, <NUM> to match volume fluctuations that may arise in a patient's body cavity as they occur. The first and second proportional outlet line valves <NUM>, <NUM> provide the gas delivery system <NUM> with fine control of insufflation gas flow rate to achieve stable flow rates at lower pressure, reduce pressure oscillation and eliminate pneumatic hammer.

Because the first and second proportional outlet line valves <NUM>, <NUM> are proximal to the patient where flow friction losses are relatively low, the gas delivery system <NUM> is able to measure peritoneal pressures accurately. Moreover, the use of proportional outlet line valves for this purpose is uniquely possible here, because there is constant gas recirculation throughout the gas delivery system <NUM>, either by way of closed loop smoke evacuation or by way of the gas sealed access port <NUM>.

Proportional valves allow for infinitely variable gas flow adjustment between a minimum flow state and a maximum flow state. Given that some volume changes in a patient's body cavity, such as breathing, are expected and consistent, by employing proportional outlet line valves, the insufflation manifold <NUM> is able to dynamically alter the gas flow to the body cavity to inverse the expected volume changes, resulting in a neutral effect on the pressure inside the cavity.

An additional benefit of using proportional valves for controlling the outflow of insufflation gas from manifold <NUM> is a reduction in response time, as compared to that of a solenoid valve. A solenoid valve operates by applying energy to coils, which produces an electromagnetic force that moves a piston. However, the energizing of the coils takes some amount of time, introducing a delay between a commanded action and the physical movement of the piston. In contrast, proportional valves, as employed in the gas delivery system <NUM> of the present disclosure, do not have an energization delay in general, and so they have an improved response time as compared to solenoid valves.

The insufflation manifold <NUM> further includes a first patient pressure sensor (PWS1) <NUM> downstream from the first outlet line valve <NUM> and a second patient pressure sensor (PWS1) <NUM> downstream from the second outlet line valve <NUM>. These two patient pressure sensors are used to measure abdominal pressure to control outlet line valves <NUM>, <NUM>, respectively. Two other pressure sensors are located upstream from the outlet line valves <NUM>, <NUM>, and are labeled as DPS1 and DPS2. These two pressure sensors are situated within a venturi to measure a pressure differential that is used to infer a total gas flow rate from the insufflation manifold <NUM> to the patient's body cavity.

A primary proportional valve (PRV) <NUM> is also operatively associated with insufflation manifold <NUM> and it is located upstream from the first and second outlet line valves <NUM>, <NUM> to control the flow of insufflation gas to the first and second outlet line valves <NUM>, <NUM>. Proportional valve <NUM> functions to maintain an intermediate pressure within the insufflation manifold <NUM> (as the central node in the LPU) at a constant pressure between <NUM> and <NUM> mmHg, dependent on the system operating mode. The opening of PRV <NUM> can be indirectly initiated by any of the following actions: patient respiration, gas leakage downstream of PRV <NUM>, or the opening of the safety valve LSV <NUM> or ventilation valve VEV <NUM>, i.e. any event that causes an intermediate pressure to drop. In the system. LSV <NUM> and VEV <NUM> are described in more detail below.

The gaseous sealing manifold <NUM> also includes a high pressure gas fill valve (GFV) <NUM> that is operatively associated with an outlet side of the compressor <NUM>. GFV <NUM> is adapted and configured to control gas delivered into the gaseous sealing manifold <NUM> from the source of surgical gas <NUM>. Preferably, the gas fill valve <NUM> is a proportional valve that is able to dynamically control surgical gas delivered into the gaseous sealing manifold <NUM>.

The gaseous sealing manifold <NUM> also includes a smoke evacuation valve (SEV) <NUM> that is operatively associated with an outlet side of the compressor <NUM> for dynamically controlling gas flow between the gaseous sealing manifold <NUM> and the insufflation manifold <NUM> under certain operating conditions, such as, for example, when the gas delivery device <NUM> is operating in a smoke evacuation mode. Preferably, the smoke evacuation valve <NUM> is a proportional valve.

A bypass valve (SPV) <NUM> is positioned between an outlet side of the compressor <NUM> and an inlet side of the compressor <NUM> for controlling gas flow within the gaseous sealing manifold <NUM> under certain operating conditions. Preferably, the bypass valve <NUM> is a proportional valve, which is variably opened to establish and control the gaseous seal generated within gas sealed access port <NUM>. Moreover, bypass valve <NUM> controls gas flow rate to the gaseous seal using feedback from pressure sensors <NUM>, <NUM>, described in further detail below.

The gaseous sealing manifold <NUM> also includes an air ventilation valve (AVV) <NUM>, which is operatively associated with an inlet side of the compressor <NUM> for controlling the entrainment of atmospheric air into the system <NUM> under certain operating conditions. For example, AVV <NUM> will permit the introduction of atmospheric air into the gaseous sealing circuit to increase the air mass (i.e., the standard volume) within the circuit. The thermodynamics of clinical use conditions can cause a loss of standard volume within the gas circuit. The ventilation valve <NUM> permits the gas delivery system <NUM> to make up for this lost volume, in order to ensure that pump pressure and flow rates are sufficient to maintain the gaseous seal within the gas sealed access port <NUM>. The ventilation valve <NUM> can also be opened to reduce the vacuum side pressure in the gas seal circuit.

An overpressure relief valve (ORV) <NUM> is operatively associated with an outlet side of the compressor <NUM> for controlling a release of gas from the system <NUM> to atmosphere under certain operating conditions. Preferably, the overpressure relief valve <NUM> is a proportional valve that is opened to reduce the positively pressurized side of the gas seal circuit, especially in the event of an emergency, such as a loss of power to the gas delivery system <NUM>. The normally open configuration of relief valve <NUM> reduces the risk of over-pressurization of the patient cavity upon loss of power to that valve.

A first pressure sensor (RLS) <NUM> is operatively associated with an inlet side of the compressor <NUM> and a second pressure sensor (PLS) <NUM> is operatively associated with an outlet side of the compressor <NUM>. These pressure sensors <NUM>, <NUM> are situated to have unobstructed and minimally restricted commutation with the patient's abdominal cavity in order to continuously and accurately measure cavity pressure. The signals from these two pressure sensors <NUM>, <NUM> are employed by a controller of the gas delivery system <NUM> to modulate the opening of the two outlet line valves <NUM> and <NUM>, to control the patient cavity pressure.

In addition, the gaseous sealing manifold <NUM> includes a gas quality sensor <NUM> that is operatively associated with an outlet side of the compressor <NUM>. The gas quality sensor monitors the level of oxygen in the recirculation circuit, which corresponds to a concentration of CO<NUM> in the body cavity of a patient, as disclosed in <CIT>.

A first blocking valve (BV1) <NUM> is operatively associated with an outlet flow path of the gaseous sealing manifold <NUM> and a second blocking valve (BV2) <NUM> is operatively associated with an inlet flow path to the gaseous sealing manifold <NUM>. The blocking valves <NUM>, <NUM> are employed during a self-test prior to a surgical procedure, as disclosed in <CIT>. It is envisioned that the first and second blocking valves <NUM>, <NUM> could be are mechanically actuated or pneumatically actuated.

A first filter element <NUM> is positioned downstream from the first blocking valve <NUM> for filtering pressurized gas flowing from the compressor <NUM> to the gas sealed access port <NUM>, and a second filter element <NUM> is positioned upstream from the second first blocking valve <NUM> for filtering gas returning to the compressor <NUM> from the gas sealed access port <NUM>. Preferably, the filter elements <NUM>, <NUM> are housed within a common filter cartridge, as disclosed for example in <CIT>.

The first and second blocking valves <NUM>, <NUM> communicate with a blocking valve pilot (BVP) <NUM> that is included within with the insufflation manifold <NUM>. Preferably, the blocking valve pilot <NUM> is a solenoid valve. It is envisioned that BVP <NUM> could be fed from the compressor outlet as shown or from a gas source such of surgical gas or air. The insufflation manifold <NUM> further includes a pressure sensor (PMS) <NUM> located downstream from the primary proportional valve <NUM> and upstream from the outlet line valves <NUM>, <NUM>. The two outlet line valves are opened to introduce insufflation gas to the patient's body cavity by way of the access ports <NUM>, <NUM>. This introduction of gas has the effect of increasing pressure within the body cavity. Additionally, the outlet line valves <NUM>, <NUM> can be opened in conjunction with air ventilation valve <NUM> to release gas from the body cavity, having the effect of desufflation and reduction of cavity pressure.

The insufflation manifold <NUM> further includes a low pressure safety valve (LSV) <NUM> downstream from the primary proportional valve <NUM> and upstream from the first and second outlet line valves <NUM>, <NUM> for controlling a release of gas from the system <NUM> to atmosphere under certain operating conditions. LSV <NUM> is a purely mechanical valve that functions to limit the maximum intermediate pressure within the manifold <NUM> or LPU (Low Pressure Unit) in the event of a power interruption, a pressure controller malfunction or if a valve located upstream from the LSV sticks in an open position.

In addition, a ventilation exhaust valve (VEV) <NUM> is positioned downstream from the primary proportional valve <NUM> and upstream from the outlet line valves <NUM>, <NUM> for controlling a release of gas from the system <NUM> to atmosphere under certain operating conditions. The ventilation exhaust valve <NUM> is a preferably a proportional valve that is opened to de-sufflate or otherwise reduce patient cavity pressure. Additionally, VEV <NUM> can be opened to reduce intermediate pressure within the LPU.

A filter element <NUM> is positioned downstream from the first outlet line valve <NUM> for filtering insufflation gas flowing from the insufflation manifold <NUM> to the valve sealed access port <NUM>. Another filter element <NUM> is positioned downstream from the second outlet line valve <NUM> for filtering insulation gas flowing from the insufflation manifold <NUM> to the gas sealed access port <NUM>. Preferably, filter element <NUM> is housed with filter elements <NUM> and <NUM> in a common filter cartridge, while filter element <NUM> is separately located.

Referring now to <FIG>, there is illustrated a gaseous sealing manifold assembly constructed in accordance with a preferred embodiment of the present disclosure and designated generally by reference numeral <NUM> which is adapted and configured for use in the gas delivery system <NUM> illustrated in <FIG>. The gaseous sealing manifold assembly <NUM> is designed as a compact, readily serviceable and replaceable modular unit. It includes a manifold body <NUM> having an inlet port <NUM> for receiving gas from an outlet side of a compressor (e.g., compressor <NUM> in <FIG>) and an outlet port <NUM> for recirculating gas to an inlet side of the compressor <NUM>. Alternatively, port <NUM> in manifold body <NUM> could be utilized for routing gas back to the inlet side of the compressor. As shown in <FIG>, the manifold body <NUM> also includes a delivery port <NUM> for delivering gas to a gas sealed access port <NUM> and a reception port <NUM> for receiving gas from the gas sealed access port <NUM> (see also <FIG>).

As best seen in <FIG>, the manifold body <NUM> defines a series of interconnected internal drilled passageways that facilitate the flow of surgical gas and air between and among the various control valves and sensors of the gaseous sealing manifold assembly <NUM>. Those skilled in the art will readily appreciate that the arrangement and location of these passageways within the manifold body <NUM> could vary by design and therefore should not be considered as a limitation on the scope of the present disclosure.

With continuing reference to <FIG> in conjunction with <FIG>, a bypass valve (SPV) <NUM> communicates with the inlet port <NUM> and the outlet port <NUM> of the manifold body <NUM>. As noted above, bypass valve <NUM> controls gas flow rate to the gaseous seal using feedback from pressure sensors <NUM> (RLS), <NUM> (PLS). The bypass valve <NUM> includes a motorized linear actuator <NUM> for dynamically controlling gas flow. The manifold body <NUM> includes a first pressure sensor port <NUM> communicating with sensor <NUM> (RLS) and a second pressure sensor port <NUM> communicating with pressure sensor <NUM> (PLS).

An air ventilation valve (AVV) <NUM> is operatively associated with the inlet side of the compressor <NUM>, upstream from the bypass valve <NUM>. The air ventilation valve <NUM> includes a motorized linear actuator <NUM> for dynamically controlling the ingress of air from atmosphere. An air ventilation port <NUM> is provided in the manifold body <NUM> for entraining atmospheric air into the air ventilation valve <NUM> (see <FIG> and <FIG>).

A smoke evacuation valve (SEV) <NUM> is operatively associated with the outlet side of the compressor <NUM>, upstream from the bypass valve <NUM>. A port <NUM> on manifold body <NUM> communicates with the smoke evacuation valve <NUM>. The smoke evacuation valve <NUM> includes a motorized linear actuator <NUM> for dynamically controlling the egress of gas from the manifold assembly <NUM> when the gas delivery system <NUM> is operating in a smoke evacuation mode.

A gas fill valve <NUM> (GFV) is operatively associated with the outlet side of the compressor <NUM>, upstream from the bypass valve <NUM>. A port <NUM> on manifold body <NUM> communicates with the gas fill valve <NUM>. The gas fill valve <NUM> includes a motorized linear actuator <NUM> for dynamically controlling the receipt of gas from the source of surgical gas.

An over pressure relief valve (ORV) <NUM> is operatively associated with the outlet side of the compressor <NUM>, downstream from the bypass valve <NUM>, for controlling the release of gas from the manifold assembly <NUM>. The over pressure relief valve <NUM> includes a solenoid actuator <NUM> with a spring loaded valve stem <NUM> located within a side housing <NUM> supported on an upstanding bracket <NUM>. Because this valve must be able to open in the event of a power loss, it is the only valve in the manifold assembly that is not driven by a motorized liner actuator.

The manifold body <NUM> also includes a gas quality sensor <NUM> that is operatively associated with the outlet side of the compressor <NUM>, downstream from the bypass valve <NUM>. The gas quality sensor monitors a level of CO<NUM> in gas recirculating through the manifold assembly <NUM> so that the gas delivery system <NUM> can make adjustments to gas quality if necessary.

Referring now to <FIG>, each motorized linear actuator (<NUM>, <NUM>, <NUM>, <NUM>) includes a respective rack and pinion mechanism to effectuate precise dynamic control of a respective valve. Each rack and pinion mechanism includes a respective horizontal actuation shaft (<NUM>, <NUM>, <NUM>, <NUM>) and a respective corresponding horizontal drive rack gear (<NUM>, <NUM>, <NUM>, <NUM>). In addition, each motorized linear actuator (<NUM>, <NUM>, <NUM>, <NUM>) includes a rotatable drive pinion gear (<NUM>, <NUM>, <NUM>, <NUM>) that is driven by the horizontal drive rack gear (<NUM>, <NUM>, <NUM>, <NUM>), and a vertical driven rack gear (<NUM>, <NUM>, <NUM>, <NUM>) that is driven by the driven pinon gear (<NUM>, <NUM>, <NUM>, <NUM>) and operatively associated with a spring-loaded vertical valve stem (<NUM>, <NUM>, <NUM>, <NUM>). Each horizontal drive rack gear (<NUM>, <NUM>, <NUM>, <NUM>) is mounted to translate along a first horizontal axis, and each rotatable driven pinion gear (<NUM>, <NUM>, <NUM>, <NUM>) is mounted to rotate about a second horizontal axis that extends perpendicular to the first horizontal axis.

In use, upon receiving a command from a controller of gas delivery system <NUM>, linear movement of a horizontal actuation shaft (right or left) will cause corresponding liner movement of an associated horizontal gear rack (right or left), which will rotate a corresponding pinion gear (clockwise or counter-clockwise). That pinon gear will then move an associated vertical drive rack (up or down), which in turn will control the upward or downward movement of a corresponding valve stem (<NUM>, <NUM>, <NUM>, <NUM>) of a control valve (<NUM>, <NUM>, <NUM>, <NUM>).

The four motorized linear actuators (<NUM>, <NUM>, <NUM>, <NUM>) are grouped together in two oppositely oriented pairs on manifold body <NUM>. More particularly, the linear actuator <NUM> of the gas fill valve <NUM> and the linear actuator <NUM> of the smoke evacuation valve <NUM> are grouped together within a first housing <NUM>. And, the linear actuator <NUM> of the bypass valve <NUM> and the linear actuator <NUM> of the air ventilation valve <NUM> are ganged together within a second housing <NUM>. Front and rear upper transverse spacer rods <NUM> and <NUM> provide structural rigidity to the first housing <NUM>, while front and rear upper transverse spacer rods <NUM> and <NUM> provide structural rigidity to the second housing <NUM>. A lower transverse spacer rod <NUM> provides further structural rigidity to the first housing <NUM>, and a lower transverse spacer rod <NUM> does the same for the second housing <NUM>. Those skilled in the art will appreciate from the figures that the flat ribbon cables associated with each of the linear actuators (<NUM>, <NUM>, <NUM>, <NUM>) extend to a controller of the gas delivery system <NUM> which delivers power and control signals to the four actuators.

Referring now to <FIG>, there illustrated another gaseous sealing manifold assembly constructed in accordance with a preferred embodiment of the present disclosure and designated generally by reference numeral <NUM> which is adapted and configured for use in the gas delivery system <NUM> illustrated in <FIG>. Manifold assembly <NUM> is substantially similar to manifold assembly <NUM> shown in <FIG>, in that it includes the same proportional control valves for dynamically controlling gas flow (i.e., GFV, SEV, SPV and AVV), but in this embodiment, these proportional control valves have respective motorized rotary actuators <NUM>, rather the than motorized linear actuators (<NUM>, <NUM>, <NUM>, <NUM>) described above.

More particularly, as shown in <FIG>, each motorized rotary actuator <NUM> includes an axial drive screw <NUM> that is supported for vertical translation within a housing <NUM> driven by a DC rotary stepper motor <NUM>. In each rotary actuator, the axial drive screw <NUM> is operatively associated with a spring-loaded vertical valve stem <NUM> associated with a respective one of the four control valves <NUM>, <NUM>, <NUM>, <NUM> depicted in <FIG>. In use, rotation of the drive screw <NUM> causes corresponding vertical movement of the valve stem <NUM> to dynamically adjust the amount of gas flowing through the associated control valve.

Alternatively, as shown in <FIG> a motorized rotary actuator <NUM> may be employed in gaseous sealing manifold assembly <NUM> for dynamically controlling gas flow, each of which includes a reduction gear assembly <NUM> that is supported within a housing <NUM> driven by a DC rotary stepper motor <NUM>. The reduction gear assembly reduces the torque generated by the stepper motor. In each rotary actuator, the reduction gear assembly <NUM> is operatively associated with a drive screw <NUM> and a spring-loaded vertical valve stem <NUM> connected thereto. In use, actuation of the reduction gear assembly causes corresponding vertical movement of the drive screw <NUM> and attached valve stem <NUM> to dynamically adjust the amount of gas flowing through the associated control valve (i.e., <NUM>, <NUM>, <NUM>, <NUM>).

While the gas delivery system and gaseous sealing manifold assembly of the present disclosure has been shown and described with reference to preferred embodiments, those skilled in the art will readily appreciate that changes and/or modifications may be made thereto without departing from the scope of the present disclosure.

Claim 1:
A manifold assembly (<NUM>) for a surgical gas delivery system (<NUM>) comprising:
a) a manifold body (<NUM>) including an inlet port (<NUM>) for receiving gas from an outlet side of a compressor (<NUM>) and an outlet port for recirculating gas to an inlet side of the compressor (<NUM>);
b) a bypass valve (<NUM>) communicating with the inlet port (<NUM>) and the outlet port of the manifold body (<NUM>), wherein the bypass valve (<NUM>) includes an electro-mechanical valve actuator for dynamically controlling the flow of gas through the bypass valve (<NUM>);
c) an air ventilation valve (<NUM>) operatively associated with the inlet side of the compressor (<NUM>), upstream from the bypass valve (<NUM>), wherein the air ventilation valve (<NUM>) includes an electro-mechanical valve actuator for dynamically controlling the ingress of air from atmosphere;
d) a smoke evacuation valve (<NUM>) operatively associated with the outlet side of the compressor (<NUM>), upstream from the bypass valve (<NUM>), wherein the smoke evacuation valve (<NUM>) includes an electro-mechanical valve actuator for dynamically controlling the egress of gas from the manifold assembly (<NUM>) when the gas delivery system (<NUM>) is operating in a smoke evacuation mode; and
e) a gas fill valve (<NUM>) operatively associated with the outlet side of the compressor (<NUM>), upstream from the bypass valve (<NUM>), wherein the gas fill valve (<NUM>) includes an electro-mechanical valve actuator for dynamically controlling the receipt of gas from a source of surgical gas.