Patent Description:
High frequency oscillatory impact to a patient's chest wall can encourage freeing of mucus from the upper respiratory tract. For example, patient suffering from mucus build up, such as cystic fibrosis patients, can be successfully treated with HFCWO therapy. Yet, generating high frequency oscillation force can be challenging.

<CIT> discloses a blood transfusion device, comprising an infusion catheter and a blood transfusion pump. The blood transfusion pump is provided with a planetary wheel and a limiting device capable of fixing the position of the infusion catheter, and one end of the planetary wheel is connected with a driving device capable of driving the rotation of the planetary wheel. The planet wheel is installed with a number of freely rotatable rollers in the circumferential direction, a section of the infusion catheter is a silicone pump tube, the silicone pump tube is pressed and wound around several rollers, and the infusion catheter is located at one end of the silicone pump tube. Dripper and blood filter for droplet rate. The roller in the blood transfusion device is in full contact with the silicone pump tube. The revolution of the planetary wheel and the rotation of the roller can roll out the liquid in the silicone pump tube to achieve the purpose of infusion. The silicone pump tube has certain elasticity and wear resistance, and is subject to. It can quickly restore the shape after pressing, and is not easy to be damaged, has good uniformity, small pulsation, and is not easy to damage the red blood cells in the blood, which can improve the safety and effectiveness of the blood transfusion process.

<CIT> discloses a battlefield wounded person carrying type differential-pressure-free blood transfusion and infusion device which is carried about by a wounded person. A casing of the device is divided into an upper layer and a lower layer, wherein an infusion bag or a blood transfusion bag is arranged on the upper layer, a circuit board and a small motor are installed on the lower layer, and a rotation disc is installed on a shaft of the small motor. <NUM> rolling wheels are evenly distributed on the circumference of the rotation disc, wherein the axis of the small motor serves as the circle center of the circumference, an infusion tube is arranged between the rolling wheels and a circular-arc press plate under the rolling wheels, the left end of the infusion tube is connected with the infusion bag on the upper layer of the casing, and the right end of the infusion tube is connected with a syringe needle. The motor drives the rolling wheels to rotate, liquid medicine in the infusion tube is extruded out and infused into a human body. The infusion bag, the infusion tube and the syringe needle are disposable, and the device is convenient to operate, safe, reliable and free of cross infection, provides reliable guaranty for rescue of battlefield wounded persons and meanwhile provides convenience for patients in hospitals.

The present invention, according to an aspect of the present disclosure, is defined by the appended claims.

In some embodiments, the at least one plunger may include at least three plungers each arranged circumferentially spaced apart from each other about a rotational axis of the drive shaft. The plunger assembly may include a track assembly including at least one guide track assembly engaged with each of the at least three plungers for guiding reciprocating motion. The track assembly may include first and second frame portions spaced apart from each other. The at least one guide track assembly may include at least three guide tracks defined by each of the first and second frame portions.

In some embodiments, each plunger may engage one of the guide tracks of each of the first and second frame portions. The guide tracks of the first and second frame portions which engage each of the number of plungers may be arranged at the same circumferential position about the rotational axis. The guide tracks which engage the same plunger may extend radially at the same angle about the rotational axis.

In some embodiments, the at least three plungers may be arranged circumferentially spaced apart from each other by about <NUM> degrees about the rotational axis. Each plunger may extend longitudinally along the rotational axis and may engage the first and second frame portions at longitudinal ends thereof. Each plunger may be arranged radially outward of the at least one diaphragm.

In some embodiments, the at least one diaphragm may include a diaphragm bladder arranged to engage with each of the at least three plungers. In some embodiments, radial motion of the at least three plungers may compress the diaphragm bladder to increase fluid pressure. The at least one diaphragm may include a diaphragm bladder extending along a rotational axis of the drive shaft.

In some embodiments, the diaphragm bladder may define the pressure cavity within a bladder compartment. The drive shaft may extend through diaphragm bladder. The drive shaft may be formed to include a pressure passage extending through at least a portion thereof.

In some embodiments, the drive shaft may include a number of openings in communication with the pressure passage and the pressure cavity to communicate fluid therebetween. The pressure passage may include a pressure port for communication with a high frequency chest wall oscillation garment to communicate pressure between the pressure cavity and the high frequency chest wall oscillation garment. Each of the at least one cam may be engaged with the at least one plunger for communicating rotational force of the drive shaft for movement of the at least one plunger. In some embodiments, each of the at least one cam may include a drive plate extending radially from the drive shaft and rotationally coupled with the drive shaft to receive rotational drive.

In some embodiments, each drive plate may include at least one cam surface engaged with the at least one plunger. Each of the at least one cam surface may be defined within a radial wall of the drive plate. Each of the one cam surface may be formed as a radially inward facing surface engaged with the at least one plunger to drive the at least plunger radially in reciprocal motion.

In some embodiments, each of the at least one cam surface may be formed as an annular surface. Each of the at least one cam surface may be formed to have triangular shape. The at least one cam may include at least two cams each engaged with the at least one plunger. The at least one plunger may include at least three plungers each engaged with each of the at least two cams.

In some embodiments, each of the at least one plunger may include a plunger body extending longitudinally along a rotational axis of the drive shaft, the body defining a curved surface on a radially inner side. The curved surface may define a convex curvature profile along the longitudinal extent of the plunger body. In some embodiments, each at least one plunger may include at least one track follower connected with the plunger body for engagement with a track assembly of the drive assembly for guiding reciprocating motion of the at least one plunger.

In some embodiments, the at least one track follower may include at least two track followers. One track follower of the at least two track followers may be connected at each longitudinal end of the plunger body. Each at least one track follower may be formed as an elongated-circular projection extending longitudinally from the plunger.

In some embodiments, each at least one plunger may include at least one cam follower for engagement with the at least one cam of the drive assembly to receive cam actuation. Each at least one cam follower may be formed as a cylindrical projection extending longitudinally from the plunger body. Each at least one cam follower may include at least two cam followers. One cam follower of the at least two cam followers may be connected at each longitudinal end of the plunger body. In some embodiments, the high frequency chest wall oscillation pump may comprise a base pressure source in communication with the pressure cavity to provide base line pressure.

A high frequency chest wall oscillation system may comprise a therapy garment for receiving pressurized fluid pulses to provide high frequency chest wall oscillation therapy to a patient. The high frequency chest wall oscillation system may comprise a high frequency oscillation pump which may comprise a pressure cavity for fluid pressurization to provide pressure oscillation. The pressure cavity may be defined at least in part by at least one diaphragm arranged for movement between a first position and a second position. The high frequency chest wall oscillation system may comprise a drive assembly including a drive shaft arranged for rotational drive and at least one cam coupled with the drive shaft to receive rotational drive. The high frequency chest wall oscillation system may comprise a plunger assembly including a number of plungers engaged with the at least one diaphragm and coupled with the drive assembly for radial reciprocating motion to move the at least one diagram between the first position and the second position to generate fluid pressure. The high frequency chest wall oscillation system may comprise a fluid conduction system comprising at least one conduit for connection to communicate fluid pressure between the high frequency oscillation pump and the garment.

In some embodiments, the high frequency oscillation pump may further comprise a motor drive coupled with the drive shaft to provide rotational force. The drive shaft may extend from the motor drive along a rotational access. The drive shaft may be rotationally coupled with the at least one cam to provide rotational drive.

In some embodiments, each at least one cam may comprise at least one drive plate coupled concentrically with the drive shaft for rotational drive. Each at least drive plate may define a cam surface engaged with the number of plungers to convert rotational motion of the at least one drive plate to compressive force of the number of plungers on the at least one diaphragm. The at least one diaphragm may include a diaphragm bladder arranged to engage with each of the at least three plungers.

In some embodiments, the high frequency oscillation pump may further comprise a base pressure source in communication with the pressure cavity to provide base line pressure. The at least one diaphragm may comprise a diaphragm bladder defining the pressure cavity therein and providing resilient return force opposing compression by the number of plungers. During a return period of the at least one cam the number of plungers may be driven radially outward under the resilient return force.

In some embodiments, the return period may include a cam stroke allowing radially outward movement of the number of cams. The resilient return force may be the only return force opposing compression of the number of plungers during a compression period. The compression period may include a cam stroke driving radially inward movement of the number of cams.

In some embodiments, the plunger assembly may include a track assembly including at least one guide track assembly engaged with each of the number of plungers for guiding reciprocating motion. The track assembly may include first and second frame portions spaced apart from each other. The at least one guide track assembly may include a number of guide tracks corresponding with the number of plungers. The number of guide tracks may be defined by each of the first and second frame portions.

In some embodiments, each of the number of plungers may engage one of the guide tracks of each of the first and second frame portions. The guide tracks of the first and second frame portions which engage each of the number of plungers may be arranged at the same circumferential position about the rotational axis. The guide tracks which engage same one of the number of plungers may extend radially at the same angle about a rotational axis of the drive shaft.

In some embodiments, the guide tracks of the same frame portion may be arranged circumferentially spaced apart from each other by about <NUM> degrees about the rotational axis. Each of the number of plungers may extend longitudinally along a rotational axis of the drive shaft and engages the first and second frame portions at longitudinal ends thereof.

According to another aspect of the present disclosure, a high frequency chest wall oscillation pump may comprise a cylindrical bladder defining a pressure cavity for fluid pressurization to provide pressure oscillation, the bladder arranged for resilient operation between an expanded state in which the pressure cavity has an expanded volume and a compressed state in which the pressure cavity has a compressed volume less than the expanded volume, a squeeze assembly arranged for providing oscillating compression of the bladder between the expanded and compressed states. The squeeze assembly may include a drive shaft arranged for rotational drive and at least one cam coupled with the drive shaft to receive rotational drive, and at least one plunger coupled with the at least one cam for radial reciprocating motion to squeeze the bladder from the expanded state to the compressed state to generate fluid pressure.

In some embodiments, each of the at least one plungers is arranged radially outward of the cylindrical bladder. The at least one plunger may include at least two plungers. The at least at least two plungers may be circumferentially spaced apart from each other. Each of the at least two plungers may have equal circumferential spacing apart from each other.

In some embodiments, each of the at least one cam may be engaged with the at least one plunger for communicating rotational force of the drive shaft for movement of the at least one plunger. Each of the at least one cam may include a drive plate extending radially from the drive shaft and rotationally coupled with the drive shaft to receive rotational drive. Each drive plate may include at least one cam surface engaged with the at least one plunger.

In some embodiments, each of the at least one cam surface may be defined within a radial wall of the drive plate. Each of the one cam surface may be formed as a radially inward facing surface engaged with the at least one plunger to drive the at least one plunger radially in reciprocal motion. Each of the at least one cam surface may be formed as an annular surface. Each of the at least one cam surface may be formed to have triangular shape.

In some embodiments, the at least one cam may include at least two cams each engaged with the at least one plunger. The at least one plunger may include at least three plungers each engaged with each of the at least two cams. Each of the at least one plunger may include a plunger body extending longitudinally along a rotational axis of the drive shaft, the body defining a curved surface on a radially inner side. The curved surface may define a convex curvature profile along the longitudinal extent of the plunger body.

In some embodiments, each at least one plunger may include at least one track follower connected with the plunger body for engagement with a track assembly for guiding reciprocating motion of the at least one plunger. The at least one track follower may include at least two track followers, one track follower of the at least two track followers connected at each longitudinal end of the plunger body. Each at least one track follower may be formed as an elongated-circular projection extending longitudinally from the plunger body.

In some embodiments, each at least one plunger may include at least one cam follower for engagement with the at least one cam to receive cam actuation. Each at least one cam follower may be formed as a cylindrical projection extending longitudinally from the plunger body. Each at least one cam follower may include at least two cam followers, one cam follower of the at least two cam followers connected at each longitudinal end of the plunger body. In some embodiments, the high frequency chest wall oscillation pump may further comprise a base pressure source in communication with the pressure cavity to provide base line pressure. A high frequency chest wall oscillation system may comprise a therapy garment coupled with the high frequency chest wall oscillation pump to receive pressure oscillation.

According to another aspect of the present disclosure, a high frequency chest wall oscillation pump may comprise a pressure cavity for fluid pressurization to provide pressure oscillation, the pressure cavity defined at least in part by at least one diaphragm arranged for movement between a first position and a second position, a squeeze assembly including a drive shaft arranged for rotational drive and at least one cam coupled with the drive shaft to receive rotational drive, and at least one squeeze body coupled with the at least one cam for radial reciprocating motion to squeeze the at least one diaphragm from one to the other of the first and second positions to generate fluid pressure within the pressure cavity. The squeeze assembly may be adapted for more than one oscillation of the at least one diaphragm between the first and second positions for each revolution of the drive shaft.

In some embodiments, each of the at least one squeeze body may be arranged radially outward of the at least one diaphragm. The at least one squeeze body may include at least two squeeze bodies. The at least at least two squeeze bodies may be circumferentially spaced apart from each other.

In some embodiments, each of the at least two squeeze bodies may have equal circumferential spacing apart from each other. Each of the at least one cam may be engaged with the at least one squeeze body for communicating rotational force of the drive shaft for movement of the at least one squeeze body. Each of the at least one cam may include a drive plate extending radially from the drive shaft and rotationally coupled with the drive shaft to receive rotational drive.

In some embodiments, each drive plate may include at least one cam surface engaged with the at least one squeeze body. Each of the at least one cam surface may be defined within a radial wall of the drive plate. Each of the at least one cam surface may be formed as a radially inward facing surface engaged with the at least one squeeze body to drive the at least one squeeze body radially in reciprocal motion.

In some embodiments, each of the at least one cam surface may be formed as an annular surface. Each of the at least one cam surface may be formed to have triangular shape. In some embodiments, the at least one cam may include at least two cams each engaged with the at least one squeeze body.

In some embodiments, the at least one squeeze body may include at least three squeeze bodies each engaged with each of the at least two cams. Each of the at least one squeeze body may extend longitudinally along a rotational axis of the drive shaft. Each of the at least one squeeze body may define a curved surface on a radially inner side. In some embodiments, the curved surface may define a convex curvature profile along the longitudinal extent of the squeeze body.

In some embodiments, each at least one squeeze body may include at least one track follower for engagement with a track assembly for guiding reciprocating motion of the at least one squeeze body. The at least one track follower may include at least two track followers. One track follower of the at least two track followers may be connected at each longitudinal end of the at least one squeeze body.

In some embodiments, each at least one track follower may be formed as an elongated-circular projection extending longitudinally from the at least one squeeze body. Each at least one squeeze body may include at least one cam follower for engagement with the at least one cam to receive cam actuation. Each at least one cam follower may be formed as a cylindrical projection extending longitudinally from the at least one squeeze body.

In some embodiments, each at least one cam follower may include at least two cam followers. One cam follower of the at least two cam followers may be connected at each longitudinal end of the squeeze body. In some embodiments, the high frequency chest wall oscillation pump may further comprise a base pressure source in communication with the pressure cavity to provide base line pressure. In some embodiments, the squeeze assembly may be adapted for three oscillations of the at least one diaphragm between the first and second positions to generate three pressure pulses for each revolution of the drive shaft. A high frequency chest wall oscillation system may comprise a therapy garment coupled with the high frequency chest wall oscillation pump to receive pressure oscillation.

For the purposes of promoting an understanding of the principles of the disclosure, reference will now be made to a number of illustrative embodiments illustrated in the drawings and specific language will be used to describe the same.

Material within the upper respiratory system, for example, mucus build-up in the upper respiratory tract of cystic fibrosis patients, can be effectively treated by encouraging expectoration. High Frequency Chest Wall Oscillation (HFCWO) can assist in loosening build-up by applying repetitive force of impact to the patient's chest wall area.

Referring now to <FIG>, a HFCWO system <NUM> is shown including a chest engagement device <NUM> embodied as a wearable therapy garment vest, a therapeutic force generator <NUM> in communication with the vest <NUM> via one or more fluid hoses <NUM> to provide pressure force communicated by the vest <NUM> to the patient's torso region to provide impact force to the patient's chest wall. The vest <NUM> illustratively includes one or more pressurizable chambers that are arranged in communication with the HFCWO pump <NUM> to receive successive pressurization and depressurization to inflate and deflate imposing an oscillating impact force on the patient. The application of successive impact force to impose high frequency oscillation of the chest wall as a therapy regime can assist in dislodging material, such as mucus build-up, from the upper respiratory tract.

Referring to <FIG>, the HFCWO pump <NUM> includes a pump housing which is omitted to reveal internal contents. In the illustrative embodiment, the HFCWO pump <NUM> is embodied as an HFCWO pump adapted to provide oscillating fluid pressure to provide HFCWO force in the vest <NUM>. The HFCWO pump <NUM> can include a user interface, such as a touch sensitive screen, and one or more pressure connection portions for receiving connection of the hose <NUM> to communicate pressurized fluid with the vest <NUM>.

As discussed in additional detail herein, the HFCWO pump <NUM> illustratively includes a bladder <NUM> defining a pressure cavity <NUM> therein. The bladder <NUM> is embodied as a diaphragm moveable between expanded and contracted positions to alter the pressure cavity <NUM> between larger and smaller volumes to generate pressure oscillation for communication with the vest <NUM>. In some embodiments, the pressure cavity <NUM> may be defined by more than one moveable diaphragm. The HFCWO pump <NUM> illustratively includes a plunger assembly <NUM> including a number of plungers <NUM> arranged for radially reciprocating motion while engaged with the bladder <NUM> to drive compression of the bladder <NUM> by squeezing the bladder <NUM> between the expanded and contracted positions.

Referring now to <FIG>, a diagrammatic cross-section visualization of internal portions of the HFCWO pump <NUM> omits the pump housing among other portions to illustrate operation of the bladder <NUM> and plunger assembly <NUM>. The plungers <NUM> of the plunger assembly <NUM> are each arranged to engage the bladder <NUM> for reciprocating radial motion as indicated by arrows <NUM>. As shown in <FIG>, the plungers <NUM> are illustratively arranged in a radially outward position to allow the bladder <NUM> to have the expanded position, and thus the pressure cavity <NUM> to have the larger volume.

As shown in <FIG>, the plungers <NUM> are each arranged in a radially inward position relative to the radially outward position of <FIG>, thereby driving compression of the bladder <NUM> to the contracted position and compressing the pressure cavity <NUM> to the lower volume to increase pressure within the pressure cavity <NUM> for communication to the vest <NUM>. As discussed in additional detail herein, the plunger assembly <NUM> includes a track assembly <NUM> for guiding reciprocating motion of the plungers <NUM>.

Referring now to <FIG>, the track assembly <NUM> includes a pair of frame portions <NUM> defining tracks <NUM> for guiding motion of the plunger assembly <NUM>. The frame portions <NUM> are illustratively spaced apart from each other. Each frame portion <NUM> is arranged with one of the tracks <NUM> engaged with each one of the plungers <NUM> to provide guidance for radial movement.

In the illustrative embodiment, each frame portion <NUM> defines three tracks <NUM> arranged with circumferential spacing of about <NUM> degrees from each other, with each track <NUM> arranged in corresponding angular (circumferential) position with a corresponding one of the three tracks <NUM> of the other frame portion <NUM> such that pairs of tracks <NUM> of each frame portion <NUM> are arranged at the same angular (circumferential) position about the axis <NUM>. Referring to <FIG>, the frame portions <NUM> are each shown to include a foot <NUM> for mounting to a base frame <NUM> of the HFCWO pump <NUM>. The base frame <NUM> illustratively includes structural member <NUM>, embodied as a plate, for supporting a driveshaft <NUM> for rotational motion about the rotational axis <NUM>, as discussed in additional detail herein.

In <FIG>, the plungers <NUM> are shown arranged in the radially outward position, similar to <FIG>, with the bladder <NUM> omitted for description ease. In <FIG>, the plungers <NUM> are shown in the radially inward position, similar to <FIG>, with the bladder <NUM> omitted for description ease. Each plunger <NUM> remains engaged with the corresponding tracks <NUM> the frame portions <NUM> throughout the extent of their reciprocating radial movement.

Referring now to <FIG>, the HFCWO pump <NUM> includes a drive assembly <NUM> for providing drive force to the plunger assembly <NUM>. The drive assembly <NUM> includes the driveshaft <NUM> and a pair of cams <NUM> coupled with the driveshaft <NUM> to receive rotational drive from the driveshaft <NUM>. The cams <NUM> are each illustratively embodied as a drive plate <NUM> extending radially and coaxially from connection with the driveshaft <NUM>.

Each cam <NUM> is illustratively engaged with the plunger assembly <NUM> to transfer rotational motion of the drive shaft <NUM> into radial drive of the plungers <NUM>. The cams <NUM> each defining a cam surface <NUM> engaged with the plungers <NUM> to radially drive the plungers <NUM> according to the circumferential profile of the cam surface <NUM>.

Referring to <FIG>, the (right most) cam <NUM> has been rendered transparent to reveal the cam surface <NUM> embodied to have a triangular circumferential profile. Each cam surface <NUM> is formed as a continuous, radially inward facing surface, having peaks <NUM> and connecting portions <NUM> in alternating succession. The peaks <NUM> and connecting portions <NUM> are each arranged corresponding respectively with the radially outward and radially inward positions of the plungers <NUM>. The peaks <NUM> are illustratively arranged spaced apart from each other by the connecting portions <NUM> at equal circumferential positions about the rotational axis <NUM> providing.

The size and shape of the cams surfaces <NUM> of each cam <NUM> are illustratively equal and mirror images of each other. The peaks <NUM> of each cam <NUM> are arranged with equal angular (and radial) position as the peaks <NUM> of the other cam <NUM> such that longitudinal ends of the plungers <NUM> engaged with each cam surface <NUM> are driven to equal radial distance from the axis <NUM> for each angular position of the cams <NUM> via driveshaft <NUM>. The connecting portions <NUM> of each cam <NUM> are arranged with equal angular (and radial) position as connecting portions <NUM> of the other cam <NUM>.

As shown in <FIG>, the plungers <NUM> are presently arranged to engage the cam surfaces <NUM> near each corresponding peak <NUM> such that the plungers <NUM> are each arranged in the radially outward position permitting the bladder <NUM> to have the expanded position. A reference star <NUM> is shown near one of the peaks <NUM> to visually identify a reference angular point of the cams <NUM> throughout the <FIG>.

Proceeding to <FIG>, the drive assembly <NUM> has been rotated counterclockwise (in the orientation as shown in <FIG>) relative to the position in <FIG>, as observable based on comparison of the relative location of the reference star <NUM>. Each of the plungers <NUM> are no longer presently arranged to engage with the peaks <NUM> of the cam surface <NUM>, but are instead engaged with the connecting portions <NUM> at an intermediate location between adjacent peaks <NUM>. The plungers <NUM> are each presently arranged at an intermediate radial position (between the radially outward and inward positions) corresponding with their present state of engagement with the cam surface <NUM>.

Proceeding to <FIG>, the drive assembly <NUM> has been rotated further counterclockwise (in the orientation as shown in <FIG>) relative to the position in <FIG>, as observable based on comparison of the relative location of the reference star <NUM>. Each of the plungers <NUM> are presently arranged to engage with the connecting portion <NUM> of the cam surface <NUM> just a few degrees before engagement with the peaks <NUM>, and are thus engaged with the connecting portions <NUM> at an intermediate location between adjacent peaks <NUM> but closer to the next peak <NUM> than the intermediate location in <FIG>. The plungers <NUM> are each presently arranged at an intermediate radial position (between the radially outward and inward positions) corresponding with their present state of engagement with the cam surface <NUM>, and having slightly greater radial distance from the axis <NUM> than shown in <FIG>, but not quite as large as the radial distance of the radially outward position of <FIG> that corresponds with engagement of the plungers <NUM> with the peaks <NUM>.

At a middle angular position of the drive assembly <NUM> between that shown in <FIG>, the plungers <NUM> would be arranged to engage the cam surface to have the radially inward position having the shortest radial distance from the axis <NUM>. Accordingly, the plungers <NUM> are driven radially inward from the radially outward position until the middle angular position of the drive assembly <NUM>. After rotation of the drive assembly <NUM> moves beyond the middle angular position, the plungers <NUM> are each permitted by their engagement with the cam surface <NUM> to move radially outward towards the radially outward position. From the angular position of the drive assembly <NUM> in <FIG>, continued counterclockwise rotation of the drive assembly <NUM> (in the orientation as shown in <FIG>) would resume a similar position as in <FIG>, with each plunger <NUM> then being engaged by the proceeding peak <NUM> of the cam surface <NUM>, and then continuing to repeat positioning as shown in <FIG>.

Referring now to <FIG>, portions of the HFCWO pump <NUM> are shown in exploded arrangement for descriptive ease. One of the frame portions <NUM> (the right most frame portion in the orientation of <FIG>) has been omitted to show that the plungers <NUM> are each engaged with the cam surface <NUM> of one the cams <NUM> (the right most cam <NUM> in the orientation of <FIG>), and particularly at the peaks <NUM> such that the plungers <NUM> are each arranged at the radially outward position. The cams <NUM> each include a central opening <NUM> for receiving the driveshaft <NUM> for rotationally fixed coupling to receive drive rotation about the axis <NUM>.

Referring now to <FIG>, the bladder <NUM> is shown apart from other portions of the HFCWO pump <NUM>. The bladder <NUM> is illustratively formed to have cylindrical base <NUM> extending coaxially along the axis <NUM>. The base <NUM> includes a bladder wall <NUM> having an exterior surface <NUM> for engagement with the plungers <NUM>. The bladder wall <NUM> is illustratively formed of a resilient, stretchable material, such as rubber, allowing for resilient compression of the base <NUM> under the force of the plungers <NUM> to drive the pressure cavity <NUM> to the contracted position. In some embodiments, the bladder wall <NUM> may be formed of a resilient, inflexible material.

The bladder <NUM> includes a collar <NUM> extending longitudinally outward from each longitudinal end of the base <NUM>. The collar <NUM> is illustratively formed as a portion of the bladder wall <NUM> from the same resilient material, although in some embodiments, may be formed distinctly from the bladder wall <NUM> forming the base <NUM>. The collars <NUM> are each configured to engage with one of the frame portions <NUM> of the track assembly <NUM>.

Each collar <NUM> is formed as an annular wall defining an opening <NUM> therethrough arranged in communication with the pressure cavity <NUM>. The openings <NUM> are illustratively arranged to receive extension of the driveshaft <NUM> therethrough such that the driveshaft <NUM> extends through the pressure cavity <NUM>. The bladder <NUM> includes a cuff <NUM> for each collar <NUM> formed as an annular member defining an opening <NUM> for receiving the corresponding collar <NUM>. The cuffs <NUM> are adapted for enveloping the corresponding collars <NUM> to apply radially inward pressure against an outer surface <NUM> of the collars <NUM> to seal the collars <NUM> with the frame portions <NUM>.

Referring now to <FIG>, each plunger <NUM> is formed to have an elongated body <NUM> extending longitudinally between ends <NUM>, <NUM>. The body <NUM> includes an engagement surface <NUM> for engagement with the bladder <NUM>. The engagement surface <NUM> is defined on an inner side thereof extending between the ends <NUM>, <NUM>.

Each plunger <NUM> includes a track follower <NUM> at each longitudinal end <NUM>, <NUM> of the body <NUM> for engagement with the corresponding track <NUM> of the track assembly <NUM>. Each track follower <NUM> is illustratively formed as an elongated circular cross-section having elongated cross-sectional length L. The elongated cross-section of each track follower <NUM> is projected longitudinally out from the body <NUM> to define opposing lateral sides <NUM>. The sides <NUM> of each track follower <NUM> are illustratively formed to extend radially and parallel to each other for engaging the corresponding track <NUM> to receive guidance for the respective plunger <NUM> for radial movement relative to the axis <NUM>.

Each plunger <NUM> includes a cam follower <NUM> for engagement with the corresponding cam <NUM>. Each cam follower <NUM> is illustratively formed as a cylindrical projection extending longitudinally out from the respective end <NUM>, <NUM> of the body <NUM>, more specifically, connected with a longitudinally outer side of the corresponding track follower <NUM> and projecting longitudinally outward therefrom. Each cam follower <NUM> defines an exterior surface <NUM> for engagement with the cam surface <NUM> of the corresponding cam <NUM> to transfer rotational force of the driveshaft <NUM> into radial motion of the plungers <NUM>.

Each cam follower <NUM> illustratively forms a plain bearing with the corresponding cam surface <NUM>. In some embodiments, the cam followers <NUM> may include any suitable manner of bearing for engagement with the corresponding cam surface <NUM> to transfer rotational force of the driveshaft <NUM> to radial movement of the plunger <NUM>, for example, a roller bearing, fluid bearing, and/or magnetic bearing.

Referring to <FIG>, the engagement surface <NUM> of each plunger <NUM> is illustratively formed to have convex curvature along the lateral direction (orthogonal to the longitudinal direction) for engagement with the bladder <NUM>. Each plunger <NUM> defines lateral sides <NUM>. The lateral sides <NUM> are illustratively slanted to taper outwardly to an exterior (radially outer) side <NUM>.

Each track follower <NUM> extends radially (vertically in the orientation in <FIG>). Each track follower <NUM> defines an upper end <NUM> at which the exterior surface <NUM> is arranged even with the exterior side <NUM> of the body <NUM>, and a lower end <NUM> extending (radially inward) beyond the engagement surface <NUM> and defining the length L therebetween. In the illustrative embodiment, each track follower <NUM> and each body <NUM> are formed symmetrically about the longitudinal plane (symmetrical about the vertical direction in <FIG>). Referring briefly to <FIG>, each plunger <NUM> is illustratively formed symmetrically along the axial direction relative to axis <NUM> (symmetrical about the vertical direction in <FIG>). In the illustrative embodiment, the plungers <NUM> are formed separately from the bladder <NUM>, but in some embodiments, one or more plungers <NUM> may be formed partly or wholly integrated and/or connected with the bladder <NUM>, for example, by integral formation with the bladder wall <NUM>.

Referring now to <FIG>, each frame portion <NUM> of the track assembly <NUM> illustratively includes three tracks <NUM> arranged with equal circumferential spacing from each other about axis <NUM>. Each frame portion <NUM> includes a hub <NUM> formed concentrically with axis <NUM> and defining a shaft opening <NUM> for receiving the driveshaft <NUM>. Each frame portion <NUM> includes track struts <NUM> extending radially from the hub <NUM> for connection with an outer annulus <NUM>.

The track struts <NUM> each define one of the tracks <NUM> therein for receiving sliding engagement of the track followers <NUM>. The tracks <NUM> are each formed to include a receiver space <NUM> defined in the track struts <NUM> between radially extending sides <NUM>. The receiver space <NUM> illustratively receives the corresponding track follower <NUM> therein such that the sides <NUM> of the track follower <NUM> are slidingly engaged within the sides <NUM> of the track struts <NUM> to guide radial motion of the respective plunger <NUM>. Each receiver space <NUM> defines a radial length sufficient to allow travel of the track follower <NUM> corresponding with movement of the respective plunger <NUM> between the radially outward and radially inward positions.

Still referring to <FIG>, each frame portion <NUM> includes an exterior side <NUM> for arrangement facing away from the bladder <NUM>, and an interior side <NUM> for arrangement facing towards the bladder <NUM>. The track struts <NUM> each connect with an outer circumference of the corresponding hub <NUM> near the exterior side <NUM> and extend for connection with an inner circumference <NUM> of the outer annulus <NUM> near the exterior side <NUM>. In the illustrative embodiment, the track struts <NUM> each extend flush with the hub <NUM> and outer annulus <NUM> on the exterior side <NUM> to form a uniformly flat exterior face <NUM>.

The hub <NUM> is illustratively formed as an annular member having a bushing <NUM> defined concentrically about the axis <NUM>. The bushing <NUM> defines the shaft opening <NUM> therethrough for receiving the driveshaft <NUM> extending therethrough in rotational engagement to provide a rotational bearing. The bushing <NUM> is illustratively embodied to form a slide bearing with the driveshaft <NUM>, but in some embodiments, may form a roller bearing, fluid bearing, magnetic bearing, and/or any other suitable bearing for rotationally supporting the driveshaft <NUM>.

Referring now to <FIG>, the outer annulus <NUM> may include a ledge <NUM> projecting radially inward from an inner circumference <NUM> of the outer annulus <NUM> to define an inner circumference <NUM> for connection with each of the track struts <NUM>. The ledge <NUM> is illustratively arranged at the exterior side <NUM> and forms a portion of the exterior face <NUM>.

Each hub <NUM> is adapted for sealing connection with the bladder <NUM>. Each hub <NUM> includes a cylindrical outer surface <NUM> extending axially along the axis <NUM> such that each hub <NUM> can be inserted into one of the collars <NUM> of the bladder <NUM> to seal against the annular interior surface of the collar <NUM> under compression by the corresponding cuff <NUM>. The cylindrical outer surface <NUM> includes an annular depression <NUM> therein that extends circumferentially about the hub <NUM>.

Referring now to <FIG>, each cam <NUM> illustratively includes the drive plate <NUM> and the cam surface <NUM> formed as a radially inward facing surface formed by a depression <NUM> in an interior side <NUM> of the drive plate <NUM>. Each cam <NUM> includes a hub <NUM> concentrically arranged relative to the axis <NUM>. Each hub <NUM> extends axially from a lateral surface <NUM> of the drive plate <NUM> defining the depression <NUM>.

Each hub <NUM> is formed to define a shaft opening <NUM> for receiving the driveshaft <NUM> for fixed rotation between the cam <NUM> and the driveshaft <NUM> about axis <NUM>. Each hub <NUM> is embodied to include a pair of key receivers <NUM> embodied as recesses formed on an interior circumference of the hub <NUM> connecting with the shaft opening <NUM> to receive fixed keys for rotational connection with the driveshaft <NUM> about the axis <NUM>. In some embodiments, rotational connection between the cam <NUM> and driveshaft <NUM> for rotation about axis <NUM> may include welding, interference fit, threading, and/or any other suitable manner of rotational connection for rotating the cams <NUM> about the axis <NUM> under power of the driveshaft <NUM>.

As shown in <FIG>, each drive plate <NUM> includes an exterior side <NUM>. The hub <NUM> illustratively projects axially beyond a surface of the exterior side <NUM>. The shaft opening <NUM> illustratively penetrates through the hub <NUM> to allow the driveshaft <NUM> to extend therethrough.

Referring now to <FIG>, portions of the HFCWO pump <NUM> are shown omitting certain other portions, such as the frame portions <NUM> and bladder <NUM>, for descriptive ease. A rotational drive motor <NUM> is illustratively connected with the driveshaft <NUM> to provide rotational drive about axis <NUM>. The drive motor <NUM> is illustratively positioned on one longitudinal end of the HFCWO pump <NUM> connected with an axial end of the driveshaft <NUM> (the connection being formed within pressure housing <NUM> as discussed in additional detail herein).

The HFCWO pump <NUM> includes a pressurizer <NUM> for providing baseline fluid pressure to the bladder <NUM>. The pressurizer <NUM> is illustratively embodied as a fluid pump arranged in fluid communication with the bladder <NUM>. The pressurizer <NUM> includes a fluid outlet <NUM> for providing pressurized fluid. The fluid outlet <NUM> is connected with a pressure housing <NUM> to communicate pressurized fluid from the pressurizer <NUM> to the bladder <NUM>. The driveshaft <NUM> extends into the pressure housing <NUM> to receive pressurized fluid therefrom for communication to the bladder <NUM>. In the illustrative embodiment, the pressure housing <NUM> forms a fluid tight seal against the hub <NUM> of the cam <NUM>.

Referring now to <FIG>, the driveshaft <NUM> extends axially along the axis <NUM> between axial ends. The driveshaft <NUM> is illustratively formed as a hollow shaft defining a flow passage <NUM> therethrough. The driveshaft <NUM> includes bladder openings <NUM> defined radially through a shaft wall <NUM> in communication with the flow passage <NUM>. The driveshaft <NUM> includes a source opening <NUM> arranged in communication with the pressurizer <NUM> to receive pressurized fluid therefrom and in communication with the flow passage <NUM> to provide pressurized fluid to the pressure cavity <NUM> for baseline pressure.

The driveshaft <NUM> extends into the bladder <NUM> to arrange the bladder openings <NUM> within the pressure cavity <NUM> of the bladder <NUM> to communicate the flow passage <NUM> with the pressure cavity <NUM>. The flow passage <NUM> provides baseline fluid pressure from the pressurizer <NUM> and flow communication with the therapy vest <NUM>. The driveshaft <NUM> includes a flange <NUM> on one end for connection with the drive motor <NUM>. The driveshaft <NUM> includes key holes <NUM> formed as recesses defined in the shaft wall <NUM> to receive fixed keys for rotational connection with the driveshaft <NUM> about the axis <NUM>.

Referring now to <FIG>, the pressure housing <NUM> includes a cylindrical body <NUM> extending axially along the axis <NUM> and defining a flow passage <NUM> therein. The pressure housing <NUM> includes an inlet stem <NUM> extending radially from connection with the body <NUM> for connection with the fluid outlet <NUM> of the pressurizer <NUM>. The inlet stem <NUM> includes an inlet passage <NUM> defined therethrough in communication with both of the fluid outlet <NUM> and the flow passage <NUM> for communicating pressurized fluid from the pressurizer <NUM> to the bladder <NUM>. The pressure housing <NUM> includes a flange <NUM> for engagement with the cam <NUM>.

Referring to <FIG>, the HFCWO pump <NUM> includes an outlet cap <NUM>. The outlet cap <NUM> is illustratively arranged to abut the corresponding cam <NUM> on an end of the HFCWO pump <NUM> opposite to the drive motor <NUM>. The outlet cap <NUM> includes a cap plate <NUM> having an annular cap wall <NUM> extending concentrically from the cap plate <NUM> towards the cam <NUM> for engagement therewith. The outlet cap <NUM> includes an annular exit <NUM> extending concentrically from the cap plate <NUM> opposite the cap wall <NUM>. The annular exit <NUM> includes inner <NUM> and outer <NUM> annular walls spaced radially apart from each other to define a receiving gap <NUM>. The inner annular wall <NUM> defines a shaft passage <NUM> penetrating through the outlet cap <NUM> to receive the drive shaft <NUM> extending therethrough.

The outlet cap <NUM> includes an o-ring <NUM> (as shown in <FIG>) and outlet stem <NUM> each arranged to be received within the receiving gap <NUM> (as shown in <FIG>) <NUM>. The outlet stem <NUM> defines a flow passage <NUM> for communication of the shaft flow passage <NUM> with an outlet <NUM> defined on an outward end of the outlet stem <NUM> for connection with the fluid hose <NUM>. The o-ring <NUM> is arranged to abut an inner face wall of the outlet cap <NUM> within the receiving gap <NUM> and an annular face <NUM> of the outlet stem <NUM> for fluid tight connection.

Referring to <FIG>, the pressure and volume of the HFCWO pump <NUM> according to the angular position of the driveshaft <NUM>, and therefore cams <NUM>, is shown in graphical form. Each complete <NUM> degree rotation of the driveshaft <NUM> provides three complete pumping periods in which the plungers <NUM> are reciprocated through their radially inward and outward positions. Accordingly, a single pump period, including operating the bladder <NUM> through contraction and expansion positions, can occur within <NUM> degrees of driveshaft <NUM> rotation. In the illustrative embodiment, the baseline pressure is embodied to be about <NUM> psi and the maximum pressure of each fluid oscillation is about <NUM> psi, although in some embodiments, any suitable range of baseline and/or maximum pressures may be applied.

The volume of the pressure cavity <NUM> within bladder <NUM> reflects the pressure-angle operation, yet generates four pressure maximum instances within <NUM> degrees of rotation of the driveshaft <NUM>. In the illustrative embodiment, the maximum volume of the pressure cavity <NUM> is embodied to be about <NUM> cubic feet (about <NUM> cubic meters) and the minimum volume of the pressure cavity <NUM> during each fluid oscillation is about <NUM> cubic feet (about <NUM> cubic meters). Although exemplary volumes and pressures have been illustrated, devices, systems, and methods within the present disclose may apply any suitable volumes and/or pressure.

Accordingly, devices, systems, and methods with the present disclosure can reduce losses of the HFCWO pump <NUM> providing greater efficiency in high frequency chest wall oscillation operation. For example, devices, systems, and methods with the present disclosure can require less revolution speed than traditional high frequency chest wall oscillation designs, reducing dissipative losses.

Claim 1:
A high frequency chest wall oscillation pump (<NUM>), comprising:
a pressure cavity (<NUM>) for fluid pressurization to provide pressure oscillation, the pressure cavity (<NUM>) defined at least in part by at least one diaphragm arranged for movement between a first position and a second position,
a squeeze assembly including a drive shaft (<NUM>) arranged for rotational drive and at least one cam (<NUM>) coupled with the drive shaft (<NUM>) to receive rotational drive, and at least one squeeze body coupled with the at least one cam (<NUM>) for radial reciprocating motion to squeeze the at least one diaphragm from one to the other of the first and second positions to generate fluid pressure within the pressure cavity (<NUM>), wherein the squeeze assembly is adapted for more than one oscillation of the at least one diaphragm between the first and second positions for each revolution of the drive shaft (<NUM>); and
characterised in that each of the at least one cam surface (<NUM>) is formed as a radially inward facing surface engaged with the at least one squeeze body to drive the at least one squeeze body radially in reciprocal motion.