Patent Description:
This invention relates generally to a syringe assembly and, more particularly, to a syringe assembly including a rotary piston pump configured to draw fluid from the syringe in precise volumes.

During use of a conventional syringe assembly including a syringe barrel, fluid is drawn into the syringe barrel through a distal tip, nozzle, or needle thereof, by moving a plunger rod and plunger or stopper through a syringe barrel in a proximal direction, thereby drawing the fluid into the barrel. The process of drawing fluid into the syringe barrel is known as aspiration. Following aspiration, to perform an injection, fluid is driven from the syringe barrel by pushing the plunger and plunger rod back through the syringe barrel in the distal direction. Injection volume is controlled by observing the position of the plunger and/or plunger rod within the syringe barrel and/or the distance traveled by the plunger within the barrel during the injection. Such injections may be performed manually (e.g., by grasping the proximal end of the plunger rod and manually pushing the plunger rod in the distal direction) or automatically with a syringe pump (e.g., a syringe pump having a linear actuator for automatically advancing the plunger rod and/or plunger through the syringe barrel).

Precisely controlling movement of the plunger through the syringe barrel and the resulting injection volume can be difficult due to friction and break-loose forces between the plunger and interior sidewall of the syringe barrel. For example, precisely controlling delivery of small fluid volumes from a syringe is made difficult due to static friction or stiction forces between the syringe barrel and plunger. Stiction refers to static friction that needs to be overcome to enable relative motion of stationary objects in contact, such as the plunger and the interior sidewall of the syringe barrel. As a result of the stiction forces, movement of the plunger through the barrel tends to be jerky or inconsistent since, after the static friction forces holding the plunger against the syringe barrel sidewall are overcome, the plunger may jerk or push forward through the barrel. The jerky movement means that fluid is not delivered from the syringe barrel at a constant rate, which makes controlling fluid delivery volume imprecise. Previously, syringe stiction reduction has typically been considered for ergonomic reasons, but also because it introduces a noise factor into the accuracy of conventional syringe pumps. Stiction control or reduction is typically approached in the context of lubricants or stopper design.

However, there is a need in the art for improved solutions for addressing stiction and for enabling delivery of precise volumes of fluid from a syringe barrel. Desirably, such solutions would be based on the mechanical configuration of the syringe assembly or syringe pump drive unit and would not require including additional lubricants or coatings on the plunger or stopper. The syringe assembly, fluid delivery system, and methods disclosed herein are intended to address these issues. A medical pump for dispensing very accurately dosed small amounts of a medicine is described in <CIT>.

The present invention is directed to a syringe as defined by the features of claim <NUM>. Preferred embodiments are defined within the depending claims.

According to an aspect of the disclosure, a syringe includes: a syringe barrel having an open proximal end, a closed distal end, and a sidewall extending therebetween; a plunger having an annular sidewall configured to seal against an interior surface of the sidewall of the syringe barrel, the plunger being configured to move through the syringe barrel in proximal and distal directions; a rotary piston pump in fluid communication with an interior volume of the syringe barrel configured to draw fluid from the syringe barrel by rotation of a piston; and a nozzle. The nozzle includes a lumen in fluid communication with the rotary piston pump configured to receive fluid drawn from the syringe barrel by the pump and to expel the fluid through a distal end of the lumen.

In some examples, the rotary piston pump is a rotary valve-less piston pump. A rotary valve-less piston pump can include an annular body having an open proximal end and a closed distal end, which define a cavity. The cavity can be in fluid communication with the interior volume of the syringe barrel and the lumen of the nozzle. The piston can be slidably and rotatably inserted in the cavity. When the piston is in a partially retracted position, fluid flow between the lumen of the nozzle and the interior volume of the syringe barrel through the cavity of the pump can be permitted, and fluid flow through the open proximal end of the annular body can be prevented. Movement of the piston in an axial direction into the cavity from the partially retracted position can cause the piston to seal at least one of the lumen of the nozzle or the interior volume of the syringe barrel, such that fluid communication between the cavity and the nozzle and/or the syringe barrel is prevented.

In some examples, during a piston stroke, the piston rotates <NUM> degrees and moves axially through the cavity between a seated position, a suction position, and back to the seated position. In the suction position, fluid can be drawn from the interior of the syringe barrel into the cavity. In the seated position, fluid can be expelled from the cavity through the lumen of the nozzle. A fluid volume expelled from the cavity through the lumen during each piston stroke may be from about <NUM> to <NUM>.

In some examples, the annular body includes at least one annular seal extending from an interior sidewall thereof, the seal being configured to prevent fluid from leaking from the open proximal end of the annular body. Optionally, the nozzle further includes a male luer connector configured to connect to a female luer connector of another fluid delivery device to establish fluid communication between the syringe and the fluid delivery device. Alternatively, the nozzle can include a threaded connector comprising an annular body having threads on an interior surface thereof.

In some examples, the pump is integrally molded to the syringe barrel. The pump can also be removably connected to the syringe barrel.

According to another aspect of the invention, a fluid delivery system including a syringe as defined in claim <NUM> and a drive unit. The syringe includes: a syringe barrel having an open proximal end, a closed distal end, and a sidewall extending therebetween; a plunger having an annular sidewall configured to seal against an interior surface of the sidewall of the syringe barrel and configured to move through the syringe barrel in proximal and distal directions; a rotary piston pump in fluid communication with an interior volume of the syringe barrel configured to draw fluid from the syringe barrel by rotational movement of a piston; and a nozzle. The nozzle includes a lumen in fluid communication with the pump and configured to receive fluid drawn from the syringe barrel by the pump and to expel the fluid through a distal end of the lumen. The drive unit is connected to the pump for actuating the pump to draw fluid from the interior volume of the syringe barrel.

In some examples, the rotary piston pump is a rotary valve-less piston pump. The rotary valve-less piston pump can include an annular body having an open proximal end and a closed distal end, which define a cavity. The cavity is in fluid communication with the interior volume of the syringe barrel and the lumen of the nozzle. The piston can be slidably and rotatably disposed within the cavity.

In some examples, the drive unit is removably connected to the piston and configured to move the piston through a piston stroke in which the piston rotates <NUM> degrees and moves axially through the cavity between a seated position, a suction position, and back to the seated position. The drive unit can include a rotating shaft and a cam connected to the piston.

According to another aspect of the disclosure, a method of dispensing fluid from a syringe is disclosed. The syringe includes a syringe barrel having an open proximal end, a closed distal end, and a sidewall extending therebetween; a plunger including an annular sidewall configured to seal an interior surface of the sidewall of the syringe barrel and configured to move through the syringe barrel in the proximal and distal directions; and a rotary piston pump in fluid communication with an interior volume of the syringe barrel. The rotary piston pump can be configured to draw fluid from the syringe barrel by rotational movement of a piston. The syringe can also include a nozzle having a lumen in fluid communication with the pump and configured to receive fluid drawn from the syringe barrel by the pump and to expel the fluid through a distal end of the lumen. The method for dispensing fluid from the syringe can include: filling the syringe by drawing fluid through the nozzle and into the syringe barrel, while the piston of the rotary piston pump is in a partially retracted position; and after the syringe is at least partially filled, actuating the pump to cause the piston to move through at least one piston stroke. The at least one piston stroke can include simultaneously rotating the piston <NUM> degrees and moving the piston axially through a cavity from a seated position, to a suction position, and back to the seated position to draw a volume of fluid from the syringe barrel into the cavity and to expel the volume of fluid from the syringe through the nozzle.

In some examples, the rotary piston pump is a rotary valve-less piston pump. The rotary piston pump can be moved through the at least one piston stroke automatically by a drive unit. Actuating the rotary piston pump can include performing multiple piston strokes to expel multiple discrete volumes of fluid from the syringe through the nozzle.

These and other features and characteristics of the present disclosure, as well as the methods of operation and functions of the related elements of structures and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following description and the appended claims with reference to the accompanying drawings, all of which form a part of this specification, wherein like reference numerals designate corresponding parts in the various figures. It is to be expressly understood, however, that the drawings are for the purpose of illustration and description only and are not intended as a definition of the limit of the invention.

For purposes of the description hereinafter, the terms "upper", "lower", "right", "left", "vertical", "horizontal", "top", "bottom", "lateral", "longitudinal", and derivatives thereof, shall relate to the invention as it is oriented in the drawing figures. The term "proximal" refers to a portion of a structure nearest to the center of the structure or to a point of attachment or actuation of the structure. For example, a "proximal portion" of a syringe is the portion of the syringe configured to be grasped by a user. The term "distal" refers to a portion of a structure farthest away from the center or from the point of attachment or actuation of the structure (e.g., the portion of the structure opposite from the proximal portion). For example, a "distal portion" of a syringe is the end of the syringe including the needle or nozzle.

According to an aspect of the disclosure, a syringe including a pump for drawing a precise volume of fluid from the syringe is provided. The pump can be a rotary valve-less piston pump. The syringe can be used, for example, for extracting fluid from a fluid container, such as a vial, to fill or partially fill the syringe. The filled or partially filled syringe can then be coupled to a drive unit for fluid delivery of a volume of the fluid to a patient. In other examples, the fluid can be expelled from the syringe to an IV bag for later infusion. As described herein, the syringe can be used as a conventional syringe. The syringe can be quickly converted from a conventional syringe to a precision syringe pump merely by attaching a drive unit to the pump to advance and retract the pump piston. Desirably, addition of the pump to a conventional syringe design only increases manufacturing costs for the syringe by a small amount. In some cases, the drive unit can be reusable, so that the cost of the drive unit can be amortized over many injections. In some examples, the pump is integrated directly into the syringe. In other examples, a pump assembly can be removably connected to a distal nozzle of a conventional syringe to form a syringe assembly capable of delivering precise fluid volumes.

According to another aspect of the disclosure, the syringe and pump can be integrated into a fluid dispensing system including the drive unit. For example, the drive unit may be configured to connect to the piston of the pump and to drive the piston back and forth. Driving of the piston through the pump draws fluid from an interior volume of the syringe and expels the fluid from the syringe. The drive unit can be configured to repeatedly retract and advance the piston to expel multiple precise volumes of fluid from the syringe.

A syringe <NUM> including a syringe barrel <NUM>, a pump <NUM>, and a nozzle <NUM> is shown in <FIG>. In some examples, as shown in <FIG>, the syringe barrel <NUM>, pump <NUM>, and nozzle <NUM> are integrally formed. In other examples, as shown in <FIG>, the pump <NUM> and nozzle <NUM> are removably connected to the syringe barrel <NUM>. The pump <NUM> is in fluid communication with an interior volume <NUM> of the syringe barrel <NUM> and is configured to draw fluid from the syringe barrel <NUM> and to expel fluid through the nozzle <NUM>.

As shown in <FIG>, the syringe barrel <NUM> includes an open proximal end <NUM>, a closed distal end <NUM>, and a sidewall <NUM> extending therebetween. The syringe barrel <NUM>, as well as portions of the pump <NUM> and nozzle <NUM>, can be formed from a suitable hard, rigid biocompatible material, such as plastic, glass, or metal. For example, a syringe barrel <NUM> can be formed from clear polycarbonate, so that the fluid contents in the barrel <NUM> can be observed. The syringe <NUM> also includes a stopper or plunger <NUM> configured to seal against an interior surface <NUM> of the sidewall <NUM> of the syringe barrel <NUM>. For example, the plunger <NUM> can include an annular seal <NUM> extending around an annular sidewall <NUM>, such as an elastomeric annular seal, of the plunger <NUM>. In other examples, the sidewall <NUM> can include various ridges, protrusions, or fins for creating a suitable seal between the plunger <NUM> and sidewall <NUM> of the syringe barrel <NUM>. The plunger <NUM> is configured to move through the syringe barrel <NUM> in a proximal direction (shown by arrow P in <FIG>) and distal direction (shown by arrow D in <FIG>). In some examples, as is known in the art, a plunger rod <NUM> may be removably mounted or integrally formed with a proximal portion of the plunger <NUM>. The plunger rod <NUM> can be an elongated structure including a latching mechanism (not shown) for connection with the plunger <NUM>. The plunger rod <NUM> may also include a circular disk or flange <NUM> extending from a proximal end thereof.

In some examples, the nozzle <NUM> includes a central channel or lumen <NUM> in fluid communication with the pump <NUM> configured to receive fluid drawn from the syringe barrel <NUM> and through the pump <NUM>. The lumen <NUM> can have an inner diameter of about <NUM>. In some instances, the lumen <NUM> can be necked down to a minimum inner diameter of about <NUM> to <NUM>. The narrowest portion of the lumen <NUM> may be positioned where the lumen <NUM> meets the pump <NUM>, as shown in <FIG>. The fluid is expelled from the nozzle <NUM> through a distal end of the lumen <NUM>. The nozzle <NUM> may also include a male luer connector <NUM> configured to connect to a female luer connector (not shown) of another fluid delivery device or fluid container (not shown) to established fluid communication between the syringe <NUM> and the fluid delivery device or container. The nozzle <NUM> can also include a threaded connector <NUM> including an annular body having threads on an interior surface thereof. The threads are configured to mate with corresponding threads of the fluid delivery device or fluid container to establish a more secure connection between the syringe <NUM> and the fluid delivery device or container.

The pump <NUM> can be a rotary valve-less piston pump configured to draw a precise discrete volume or dose of fluid from a fluid reservoir or fluid source, such as the interior volume <NUM>, and to expel the precise volume or dose of the fluid through the nozzle <NUM> of the syringe <NUM>. A valve-less piston pump does not include valves for controlling fluid flow through the pump and, instead, draws fluid into and expels fluid from the pump <NUM> by reciprocating motion of a piston <NUM>. A rotary valve-less piston pump can refer to a pump which actuates a piston or similar pumping mechanism by rotational movement. As a result of the rotational movement, fluid is drawn through the pump without opening and closing of valves.

In some examples, the rotary valve-less piston pump <NUM> includes an annular body <NUM> defining a cavity <NUM> and having an open proximal end <NUM> and a closed distal end <NUM>. The cavity <NUM> is in fluid communication with the interior volume <NUM> of the syringe barrel <NUM> and the lumen <NUM> of the nozzle <NUM>. In some examples, the annular body <NUM> includes at least one, and preferably two or more, annular seal(s) <NUM> (shown in <FIG>) extending from an interior sidewall of the annular body <NUM>.

In some examples, the piston <NUM> can be an elastomeric structure and the syringe barrel <NUM>, annular body <NUM> of the pump <NUM>, and nozzle <NUM> can be formed from a more rigid material (e.g., rigid plastic). The piston <NUM> can be any size and shape sufficient for drawing fluid through the cavity <NUM>. For example, as shown in <FIG>, the piston <NUM> can be a substantially cylindrical structure including a proximal portion <NUM> having a first diameter D1 substantially similar to the diameter of the cavity <NUM> and configured to contact the annular seal(s) <NUM> of the annular body <NUM> and a recessed portion <NUM> having a smaller diameter D2 to draw fluid into and expel fluid from the cavity <NUM>. For a conventional syringe, such as a <NUM> syringe, the first diameter D1 of the piston <NUM> can be from <NUM> to <NUM>.

The piston <NUM> can be moved through the cavity <NUM> by sliding the piston <NUM> into and out of the cavity (e.g., axial displacement of the piston <NUM>), by rotating the piston <NUM> in the cavity <NUM>, or by a combination of axial and rotational movement. Moving the piston <NUM> in the cavity <NUM> is intended to create suction force sufficient to draw fluid into the cavity <NUM> from the interior volume <NUM> of the syringe barrel <NUM>. Continued movement of the piston <NUM> expels the fluid from the cavity <NUM> through the lumen <NUM> of the nozzle <NUM>.

The pump <NUM> is shown with the piston <NUM> in different positions in <FIG>. In <FIG>, the piston <NUM> is in an initial or partially retracted position. In the initial or partially retracted position, the piston <NUM> is in the cavity <NUM> and spaced apart from both the lumen <NUM> of the nozzle <NUM> and from a fluid entry port <NUM> connected to the interior volume <NUM> of the syringe barrel <NUM>. Neither the lumen <NUM> nor the fluid entry port <NUM> are sealed by the piston <NUM>. In <FIG>, the recessed portion <NUM> of the piston <NUM> is shown facing the lumen <NUM> of the nozzle <NUM>. However, in the partially retracted position, the recessed portion <NUM> can be provided in any orientation as long as fluid flow through the cavity <NUM> is permitted. In the partially retracted position, fluid is prevented from leaking from the open proximal end <NUM> of the annular body <NUM> due to a seal between the piston <NUM> and the annular seal(s) <NUM>. When the piston <NUM> is in the partially retracted position, the syringe <NUM> can be used in a conventional manner. For example, fluid can be drawn into or expelled from the interior volume <NUM> of the syringe barrel <NUM> by advancing or retracting the plunger <NUM> through the syringe barrel <NUM>. Generally, the syringe <NUM> will be initially provided to a user with the piston <NUM> in the partially retracted position, so that the user can fill the interior volume <NUM> of the syringe <NUM> with fluid using the plunger <NUM>. In some examples, a cover (not shown) may be placed over the partially retracted piston <NUM> during shipping to prevent the piston <NUM> from moving during shipping and/or prior to use.

In order to attach a drive unit or similar motorized device to the piston <NUM> of the pump <NUM>, the piston <NUM> is fully inserted into the cavity <NUM> to a seated or bottom-of-stroke position, as shown in <FIG>. In this position, the piston <NUM> is fully inserted into the cavity <NUM> and the recessed portion <NUM> faces the lumen <NUM> of the nozzle <NUM>. Fluid flow from the cavity <NUM> through the lumen <NUM> is permitted. The piston <NUM> seals the fluid entry port <NUM>. This orientation of the recessed portion <NUM> is necessary, so that fluid in the cavity <NUM> can be expelled from the pump <NUM> through the lumen <NUM> at the bottom of each piston stroke.

Actuating the drive unit or motorized device retracts the piston <NUM> in a direction of arrow A1 (shown in <FIG>) from the seated position to a suction or top-of-stroke position. Simultaneously, the piston <NUM> is rotated in a direction of arrow A3 a half turn or <NUM> degrees. The suction or top-of-stroke position is shown in <FIG>. Rotating the piston <NUM> the half turn causes the recessed portion <NUM> to transition from facing the lumen <NUM> and sealing the fluid entry port <NUM> (in <FIG>) to facing the fluid entry port <NUM> and sealing the lumen <NUM> (as shown in <FIG>). Once the piston <NUM> is rotated so that it no longer seals the fluid entry port <NUM>, fluid flows from the interior volume <NUM> of the syringe barrel <NUM> into the cavity <NUM> due to a suction force generated by movement of the piston <NUM>.

As shown in <FIG>, the piston <NUM> is illustrated in a cross-over or intermediate position, in which the piston <NUM> seals both the fluid entry port <NUM> and the lumen <NUM>. In order to advance the piston from the suction or top-of-stroke position (shown in <FIG>) to the intermediate or cross-over position (<FIG>), the piston <NUM> is advanced axially into the cavity <NUM> in a direction of arrow A2 (shown in <FIG>) and rotated in the direction of arrow A3. Continued rotational and axial movement of the piston <NUM> from the intermediate or cross-over position to the seated position (<FIG>) seals the fluid entry port <NUM> and opens the lumen <NUM>. Once the lumen <NUM> is opened, a discrete dose or volume of fluid is expelled from the cavity <NUM> and into the lumen <NUM>. As shown in <FIG> and <FIG>, the piston <NUM> rotates a half turn (e.g., <NUM> degrees) between the top-of-stroke or suction position (<FIG>) and the seated position (<FIG>).

The piston <NUM> positions shown in <FIG> illustrate a full stroke of the piston pump <NUM>, in which the piston <NUM> moves axially from the seated position, to the suction position, and back to the seated position. The piston <NUM> rotates <NUM> degrees (e.g., a full rotation) during each piston stroke. Piston strokes can be repeatedly performed either manually or under power from an automated drive mechanism to draw a precise total volume of fluid from the interior volume <NUM> through the nozzle <NUM> as a series of discrete doses. For example, to manually operate the pump <NUM>, a user may grasp a portion of the proximal end of the piston <NUM> for retraction and may press against the proximal end of the piston <NUM> to advance the piston <NUM> through the cavity <NUM>. The user may also rotate or twist the piston <NUM>, as described above.

In other examples, the pump <NUM> is actuated automatically by, for example, a motor, linear actuator, or similar powered device. An exemplary drive unit <NUM>, which can be used with the pump <NUM>, is shown in <FIG>. The drive unit <NUM> includes, for example, a motor <NUM> configured to drive a shaft <NUM> and cam <NUM>. The motor <NUM>, shaft <NUM>, and cam <NUM> can be contained in a housing <NUM> configured to be mounted to a portion of the syringe <NUM> and/or pump <NUM>. For example, as shown in <FIG>, the housing <NUM> can include a lower opening <NUM> configured to receive a top portion and/or open proximal end <NUM> of the annular body <NUM> of the pump <NUM>. The lower opening <NUM> can include, for example, one or more latch members for engaging the pump <NUM> to mount the drive unit <NUM> to the pump <NUM>. The motor <NUM> can be any suitable movement-generating device, such as a battery-powered electric motor. The motor <NUM> is configured to rotate the shaft <NUM> in a direction of arrow A4. Alternatively, the motor <NUM> may twist the shaft <NUM> back and forth. For example, the motor <NUM> could twist the shaft <NUM> degrees in one direction and then <NUM> degrees in an opposite direction.

As shown in <FIG>, the shaft <NUM> is fixedly mounted to the cam <NUM>. As will be appreciated by those skilled in the art, a variety of different camming structures can be used to impart axial and/or rotational movement to the piston <NUM> from rotating motion generated by the motor <NUM>. For example, as shown in <FIG>, the cam <NUM> includes a tubular body <NUM> having a closed first end <NUM> mounted to the shaft <NUM>, an open second end <NUM> configured to receive the piston <NUM>, and a sidewall <NUM> extending between the first and second ends thereof. The piston <NUM> is received within the tubular body <NUM>. For example, a protruding portion of the piston <NUM> can be engaged by a track <NUM> extending radially outward from an inner surface <NUM> of the sidewall <NUM>. Rotation of the cam <NUM> by the shaft <NUM> causes the piston <NUM> to travel along the track <NUM> from a distal end to a proximal end thereof. As the piston <NUM> travels through the track <NUM>, the piston <NUM> moves through a piston stroke between the seated position (shown in <FIG>) and the suction position (<FIG>). In some examples, as described above, the track <NUM> can be sized, such that the piston <NUM> also rotates as it moves along the track <NUM>, in addition to moving back and forth in an axial direction.

In use, actuation of the pump <NUM> expels a volume of fluid from the syringe barrel <NUM>. For example, the syringe <NUM> and pump <NUM> can be provided to an end-user in a partially retracted position, as shown in <FIG>. The user draws fluid into the interior volume <NUM> of the syringe barrel <NUM> in a conventional manner. To actuate the pump <NUM>, the piston <NUM> is manually or automatically pushed into the cavity <NUM> to seat the piston <NUM> in the cavity <NUM>. The drive unit <NUM> is then connected to the pump <NUM> and actuated to perform at least one piston stroke. The volume of fluid per piston stroke can be an amount of fluid from about <NUM> to <NUM>. The process of retraction and seating of the piston <NUM> can be repeated multiple times to dispense additional volumes of fluid from the syringe barrel <NUM>.

In some examples, the syringe <NUM> and drive unit <NUM> can be integrated with a fluid delivery system <NUM>. An exemplary fluid delivery system <NUM> including the syringe <NUM> and electronical components of the drive unit <NUM> is shown in <FIG>. As shown in <FIG>, the fluid delivery system <NUM> includes the syringe <NUM> having the syringe barrel <NUM>, the pump <NUM>, and the nozzle <NUM> (shown in <FIG>).

The drive unit <NUM> can be connected to the pump <NUM> for actuating the pump <NUM> to draw fluid from the interior volume <NUM> of the syringe barrel <NUM>. The drive unit <NUM> includes the motor <NUM>, such as a battery powered electric motor and a power source <NUM>, such as batteries for the motor <NUM> or a plug for connecting the system <NUM> to a standard wall outlet. The drive unit <NUM> can also include a controller <NUM> for controlling retraction and advancement of the piston <NUM> to dispense a desired fluid volume from the syringe <NUM> and communications circuitry <NUM> for receiving operating instructions from an external or remote source or device. For example, information confirming that a fluid volume has been dispensed from the syringe <NUM> may be sent to the remote source with the communications circuitry <NUM>. The drive unit <NUM> can be reusable. For example, after use, the syringe <NUM> including the pump <NUM> can be removed from the drive unit <NUM> and discarded. The multi-use drive unit <NUM> can then be removably connected to another syringe <NUM> for dispensing another fluid volume. In other examples, the drive unit <NUM> can be partially or completely disposable or can be refurbished after each use.

According to another aspect of the disclosure, a method of dispensing fluid from a syringe is disclosed herein. With reference to <FIG>, as shown in a first step <NUM>, the method includes drawing fluid into the syringe barrel through a distal end of the nozzle to fill the syringe. Specifically, a user draws fluid into the syringe barrel by grasping a proximal end of a plunger rod connected to the plunger and pulling the plunger through the syringe barrel in the proximal direction. In order to draw fluid into the nozzle, the piston must be in its partially retracted position such that fluid communication from the nozzle lumen to the interior of the syringe barrel through the cavity of the pump is permitted and fluid does not leak past the piston and annular seal(s) of the annular body. After a desired amount of fluid is drawn into the syringe barrel, the syringe is ready to dispense fluid through the nozzle.

As shown in a second step <NUM>, to perform an initial pump, the piston is advanced through the cavity of the pump to a seated position. When the piston is in the seated position, a drive unit or similar motorized device can be attached to the piston to automatically move the piston through the cavity. As shown in a third step at step <NUM>, the pump piston is moved to a suction position. Specifically, the piston is moved in a proximal direction and rotated to draw fluid from the interior volume of the syringe barrel into the pump cavity. As shown in a fourth step <NUM>, the piston is then advanced axially through the cavity in the distal direction, thereby expelling the fluid from the nozzle through the lumen. As shown in a fifth step <NUM>, retracting and advancing the plunger can be repeatedly carried out to expel multiple precise volumes or doses of the fluid from the syringe.

According to another aspect of the disclosure, an assembly <NUM> for fluid delivery including a conventional syringe <NUM> and a pump assembly <NUM> removably connected to a distal end of the syringe <NUM>, such as a <NUM> syringe including a luer connector, is provided. The syringe <NUM> can be a conventional fluid-dispensing syringe including a syringe barrel <NUM> having an open proximal end <NUM>, a closed distal end <NUM>, and a sidewall <NUM> extending therebetween. As in previously described examples, a plunger <NUM> and attached plunger rod <NUM> can be inserted in and slidably sealed to an internal surface of the syringe barrel <NUM>. For example, the plunger <NUM> can include an annular seal <NUM> extending from a sidewall <NUM> of the plunger <NUM>, which is configured to press against the sidewall of the syringe barrel to form a sufficient seal. The plunger <NUM> can be configured to move through the barrel <NUM> in the proximal and distal directions to draw fluid into the syringe barrel <NUM> or to expel fluid therefrom. The syringe <NUM> also includes a nozzle <NUM> extending from the closed distal end <NUM> of the syringe barrel <NUM>. The nozzle <NUM> includes a lumen <NUM> extending longitudinally therethrough in fluid communication with an interior volume <NUM> of the syringe barrel <NUM>. The nozzle <NUM> can include a connector, such as a male luer connector <NUM>, for mounting the syringe <NUM> to a corresponding connector (e.g., a female luer connector <NUM>) of the pump assembly <NUM>. Desirably, the female luer connector <NUM> of the pump assembly <NUM> is a standard dimension configured to mount to a wide variety of commercially available syringes.

The pump assembly <NUM> can be removably connected to the nozzle <NUM> of the syringe <NUM> and in fluid communication with the interior volume <NUM> of the syringe barrel <NUM> through the lumen <NUM> of the nozzle <NUM> and a cavity <NUM> of the pump assembly <NUM>. As in previously described examples, the pump assembly <NUM> is configured to draw fluid from the syringe barrel <NUM> and to dispense the received fluid. For example, the pump assembly <NUM> may include an annular body <NUM> having an open proximal end <NUM> and a closed distal end <NUM>, which define the cavity <NUM>. The pump assembly <NUM> can further include a piston <NUM> slidably inserted in the cavity <NUM>. The pump assembly <NUM> is configured to draw fluid from the interior volume <NUM> of the syringe barrel <NUM> into the cavity <NUM> through a fluid entry or inflow port <NUM> coupled to the female luer connector <NUM>. Fluid is expelled from the cavity <NUM> through an outflow port <NUM>. In some examples, the outflow port <NUM> includes a male luer connector <NUM> or similar connecting structure for connecting the pump assembly <NUM> to another fluid delivery device or fluid container.

In use, a user obtains a conventional syringe <NUM> and connects the pump assembly <NUM> to the distal end of the syringe <NUM> by, for example, inserting the male luer connector <NUM> of the syringe nozzle <NUM> into the corresponding female luer connector <NUM> of the pump assembly <NUM>. With the piston <NUM> of the pump assembly <NUM> in the partially retracted position, the user draws fluid into the syringe <NUM> by moving the plunger rod <NUM> and plunger <NUM> in the proximal direction through the syringe barrel <NUM>. After the syringe barrel <NUM> is filled or partially filled, fluid is expelled from the syringe <NUM> by pumping the pump assembly <NUM> in the manner described hereinabove. Specifically, as previously described, retracting and advancing the piston <NUM> of the pump assembly <NUM> draws fluid from the syringe barrel <NUM> and expels the fluid through the outflow port <NUM> of the pump assembly <NUM>. After fluid dispensing is completed, the pump assembly <NUM> can be removed from the syringe <NUM> and either discarded or cleaned for reuse.

Claim 1:
A syringe (<NUM>) comprising:
a syringe barrel (<NUM>) comprising an open proximal end (<NUM>), a closed distal end (<NUM>), and a sidewall (<NUM>) extending therebetween;
a plunger (<NUM>) having an annular sidewall (<NUM>) configured to seal against an interior surface (<NUM>) of the sidewall (<NUM>) of the syringe barrel (<NUM>), the plunger (<NUM>) being configured to move through the syringe barrel (<NUM>) in proximal (P) and distal (D) directions;
a rotary piston pump (<NUM>) in fluid communication with an interior volume (<NUM>) of the syringe barrel (<NUM>) configured to draw fluid from the syringe barrel by rotation of a piston; and
a nozzle (<NUM>) comprising a lumen (<NUM>), wherein
the nozzle is in fluid communication with the rotary piston pump (<NUM>) configured to receive fluid drawn from the syringe barrel (<NUM>) by the pump (<NUM>) and to expel the fluid through a distal end of the lumen (<NUM>),
wherein, when the piston (<NUM>) is in a partially retracted position, fluid flow between the lumen (<NUM>) of the nozzle (<NUM>) and the interior volume (<NUM>) of the syringe barrel (<NUM>) through a cavity (<NUM>) of the pump (<NUM>) is permitted, with the plunger being moveable in a proximal direction to draw fluid into the interior volume (<NUM>) and being moveable in a distal direction to expel fluid from the interior volume (<NUM>).