Kit, System, and Associated Method for Filling Sealed Direct Inject Delivery Devices with Refrigerant Gas Additives

This Non-Provisional patent application claims the benefit of U.S. Non-Provisional application Ser. No. 19/242,047, filed on Jun. 18, 2025, which is incorporated herein in its entirety by reference.

Not Applicable

The invention relates to direct inject sealed delivery devices, both cartridge style and syringe style, for injecting refrigerant additives, such as drying agents or sealants, into an air conditioning system, such as the chilling system on a refrigerated appliance or an automotive air conditioning system. More specifically, it relates to a kit, system, and an associated method for filling or refilling a direct inject sealed delivery devices.

In the field of maintaining chilling systems, such as automotive air conditioning systems or chilling systems for refrigerated appliances, it is known that refrigerant additives are commonly added to the refrigerant gases. Such refrigerant additives can include sealants, including conditioners for rubber components such as O-rings, lubricants, dyes, such as UV dyes used for leak detection, system enhancers for reducing energy use or improving heat transfer, and drying agents. Frequently, these additives are sold in pre-measured, sealed delivery devices designed to inject these additives directly into the HVAC or automobile A/C system without needing to recharge the system first. These pre-measured, sealed delivery devices are commonly referred to as “direct injects” and are available as both cartridge style and syringe style devices. As used herein, “direct inject cartridges” refer to canister-style, pre-measured sealed delivery cartridges. Further, as used herein, “syringe-style direct inject” refers to the syringe style direct inject devices. The terms “direct inject” without a modifier or “direct inject delivery device” refer collectively to cartridge and syringe-style devices.

As recognized by those skilled in the art, direct injects are typically connected via the low pressure side service port. Because many of the refrigerant additives that are frequently used with direct injects are subject to being polymerized or oxidized upon exposure to air, and can be contaminated by moisture in ambient air, the direct inject cartridge is sealed against exposure to the atmosphere or moisture. Further, to avoid the possibility of air or moisture seeping into the sealed direct inject cartridge, direct inject cartridges are typically sold in sealed, air-tight packages, as seen in Prior Art. Typically, this package will also contain a desiccant pack.

Those skilled in the art recognize and understand that direct inject cartridges commonly have a self-sealing valve, commonly a Schrader-Type valve disposed at each end and a cylindrical cartridge body disposed between the two valves. These self-sealing valves are adapted to engage the low pressure port on the A/C system and similar valves on hoses and vacuum pumps designed to be compatible with an A/C system and the equipment utilized to maintain such a system. Those skilled in the art understand that with a Schrader-Type Valve and other similar valves, the valve opens when pressed and, once disconnected and the pressure on the valve is released, the valve automatically resets and seals. As understood, when manufactured, direct inject cartridges are initially filled with nitrogen which is blown through the direct inject cartridge. This step forces oxygen from the cartridge. Then, the refrigerant additive is blown into the cartridge under pressure. When the cartridge is filled with the refrigerant additive, it is not uncommon for excess refrigerant additive to escape the cartridge as it is being removed from the filling apparatus. This excess refrigerant additive is typically exposed to the atmosphere, thereby potentially exposing those working on the filling process to the refrigerant additives. Further, those skilled in the art will recognize that canister-style direct inject cartridges are single-use products and are considered disposable. This results in the metal and plastic components of the direct inject ending up in a landfill and the attendant risk of the landfill being exposed to chemical residue associated with the additives previously contained within the direct inject cartridge.

It is also known in the art that direct inject sealed delivery devices are also available as syringe-style direct injects. One such syringe-style direct inject, as illustrated in, includes, as is common with syringes, a barrel, a nozzle, a plunger seal, and some mechanism for pressing the plunger seal through the barrel to push the additives out of the nozzle. While it is known in the art that with certain syringe-style have a traditional integral plunger, plunger seal, and plunger shaft, others, such as the syringe-style direct inject illustrated in, have a plunger actuator, typically having a jack screw, that when the handle is rotated, the jack screw engages the plunger. The syringe-style direct inject plunger, in cooperation with a plunger actuator manually compresses the pre-measured refrigerant additive through the nozzle which is adapted via a threaded or quick-connect fitting to engage the low-pressure service port of the HVAC or automobile A/C system. When the plunger is depressed, internal pressure forces the additive through the service hose and valve fitting into the system, often assisted by residual system vacuum or with the aid of a pressure differential.

What is missing from the art is a kit and associated system for quickly and efficiently refilling a direct inject so that the direct inject can be reused. What is further missing from the art is a method of filling a direct inject, either filling the direct inject initially during manufacture or refilling the direct inject for reuse, that utilizes a closed, or sealed system that minimizes release of refrigerant additive to the atmosphere and that allows used direct injects to be recycled, refilled, and reused thereby reducing the burden of chemical, plastic, and metal waste currently being disposed and burdening landfills.

The present invention is directed towards various components, assemblies, and methods for filling a new direct inject cartridge and for refilling an empty used direct inject cartridge. In various embodiments, the invention provides a kit of components that may be provided together and used, in conjunction with a vacuum pump for filling a direct inject cartridge, a system in which the components are assembled and interact to facilitate filling a direct inject cartridge, and a method for using the disclosed kit and system for filling a direct inject cartridge.

The present invention is directed towards various components, assemblies, and methods for filling a new direct injects and for refilling an empty used direct inject. In various embodiments, the invention provides a kit of components that may be provided together for filling a direct inject, a system in which the components are assembled and interact to facilitate filling a direct inject, and methods for filling a direct inject. The kit and the system are adapted for use in the disclosed method. As mentioned above, the term “direct inject” used without a modifier refers to pre-measured sealed delivery devices which are available in both cartridge style devices and syringe-style devices. It will be understood that canister style cartridges have self-sealing Schrader-Type valves, referred to herein simply as Schrader valves and are designed to inject refrigerant additives directly into an air conditioning system. Such refrigerant additives can include sealants, including conditioners for rubber components such as O-rings, lubricants, dyes, such as UV dyes used for leak detection, system enhancers for reducing energy use or improving heat transfer, drying agents, or a combination of two or more of such additives. As used herein, the phrase “air conditioning system” refers broadly to an HVAC system, a chilling system for a refrigerated appliance such as refrigerators, freezers, room air conditioners, small ice makers, wine coolers, etc., or an automotive air conditioning system.

As illustrated in, kitis provided for filling, or refilling direct inject cartridge. It will be appreciated by those skilled in the art that direct inject cartridgehas a first endthat has a self-sealing valve, which in an exemplary embodiment is an externally threaded Schrader valve and a second endthat has a self-sealing valve, which, in an exemplary embodiment, has a Schrader valve with an internally threaded Schrader valve chuck. Direct inject cartridgealso includes a cylindrical bodywhich is adapted to contain a selected refrigerant gas additive. As discussed above, such refrigerant additives can include sealants, including conditioners for rubber components such as O-rings, lubricants, dyes, such as UV dyes used for leak detection, system enhancers for reducing energy use or improving heat transfer, drying agents, or a combination of two or more of such additives.

A canisteris provided which is filled with the refrigerant additive. In an exemplary embodiment, canistercontains only the refrigerant additive under at least a partial vacuum. Canisteris, in an exemplary embodiment, under negative pressure, i.e., at least a partial vacuum, to minimize the risk of exposing the refrigerant additive within canisterto atmospheric air which could oxidize or polymerize the refrigerant additive.

As will be understood by those skilled in the art, typically, a state-of-the-art aerosol canister in this art contains the refrigerant gas, or refrigerant gas additive, that is intended to be dispensed along with a pressurized gas or liquified gas, typically, a hydrocarbon gas, compressed air, or a fluorocarbon gas, collectively referred to herein as “the propellant”. The pressure of the propellant is what propels the contents of the aerosol canister out of the canister when the self-sealing valve is actuated. And, it will be recognized by those skilled in the art, that a state-of-the-art hose and can tap valve, as illustrated in, includes a fitting, a gauge, and an actuator knob. When the fittingis threadably connected to the self-sealing valve of a conventional aerosol can, actuator knobis used to selectively drive a moveable piercing pin, or valve depressor, into the self-sealing valve.

However, with the refrigerant additives utilized with the present invention, use of such a propellant creates an attendant risk of oxidizing or polymerizing the additive and also risks the propellant itself being injected into cartridge. This is not desirable because the propellant could contaminate the chilling system being worked on by a technician using direct inject cartridges for introducing a refrigerant additive into the chilling system. Unlike typical aerosol cans which utilize a propellant, canisteronly contains the refrigerant additive, preferably under negative pressure. Canisterincludes a self-sealing valveadapted to release the refrigerant additive contained therein only when the valve is actuated. In an exemplary embodiment, self-sealing valveis defined by an externally threaded self-sealing valve.

The kitfurther includes a first valve member, which is disposed between canisterand direct inject cartridge. First valve memberincludes a first endadapted to threadably engage and actuate self-sealing valve. As illustrated in, first valve memberserves as a can tap and includes a threaded collar, a pin, and a Teflon seal O-ringto ensure a proper seal with canister. Pinengages, and opens, the self-sealing valveof canister. As will be understood, pinis hollow and includes an orificewhich allows the contents of canisterto flow through pin, and first valve member. Unlike a conventional can tap, pinis fixed relative to the body of first valve member. Flow of the contents of canisteris selectively actuated by operation of valve actuator.

First valve memberfurther includes a second enddefined by a Schrader valve chuck and is adapted to engage first endof direct inject cartridgeand actuate the Schrader valve of first end. First valve memberfurther includes a valve actuatorfor selectively opening and closing the valve of first valve member. While various types of valves could be utilized, in an exemplary embodiment, first valve memberis a ball valve. First valve memberis adapted to provide selectively actuated fluid communication between canisterand direct inject cartridge.

Kitalso includes a second valve memberwhich is disposed between direct inject cartridgeand a vacuum pump. Second valve memberincludes a first endadapted to threadably engage the Schrader valve chuck of second endof the direct inject cartridgeand thereby actuate the Schrader valve of second end. Second valve memberfurther includes a second endadapted to engage a vacuum port provided on vacuum pump. Second valve memberfurther includes a valve actuatorfor selectively opening and closing the valve of second valve member. While various types of valves could be utilized, in an exemplary embodiment, second valve memberis a ball valve. Second valve memberis adapted to provide selectively actuated fluid communication between direct inject cartridgeand vacuum pump.

As seen in, kitoptionally includes a filteras a safety precaution for protection of pump. In this regard, filteris adapted to catch any refrigerant additive that may flow through direct inject cartridgeinadvertently due to an accidental opening of valve actuatorwhile valve actuatoris either completely or partially opened.

In one aspect of the present invention, the disclosure provides a system that utilizes kitfor filling a new direct inject cartridgeor refilling a used direct inject cartridge. In accordance with the disclosed system, the components of kitare assembled together as described above, and the second valve memberis connected to the vacuum port provided on vacuum pump. Alternatively, second valve memberis connected to filter, which, in turn, is connected to pump. The components of kitare assembled and, in cooperation with pump, operate in functional cooperation to fill direct inject cartridgeas will be described hereinbelow.

An alternate embodiment of the kit of the present invention is illustrated in. As illustrated in, kit′ is provided for filling, or refilling direct inject cartridge. Kit′ is adapted to provide selective fluid communication between direct inject cartridgeand either canisteror vacuum pump. As described above, direct inject cartridgehas a first endthat, in an exemplary embodiment is an externally threaded Schrader valve and a second endthat, in an exemplary embodiment, has a Schrader valve with an internally threaded Schrader valve chuck. Direct inject cartridgealso includes a cylindrical bodywhich is adapted to contain a selected refrigerant gas additive. A canisteris provided which is filled with the refrigerant additive. In an exemplary embodiment, canistercontains only the refrigerant additive under negative pressure. Canisterincludes a self-sealing valveadapted to release the refrigerant additive contained therein only when the valve is actuated.

The kit′ further includes a first valve memberwhich is disposed between canisterand a T-fittingthat is threadably engaged with direct inject cartridgein order to provide fluid communication between first valve memberand direct inject cartridge. First valve memberincludes a first endadapted to threadably engage and actuate self-sealing valve. First valve memberfurther includes a second endadapted to engage T-fitting. T-fittingincludes a Schrader chuck that engages the first endof direct inject cartridgeand actuate the Schrader valve of first end. First valve memberfurther includes a valve actuatorfor selectively opening and closing the valve of first valve member. First valve memberacting with T-fittingprovides selectively actuated fluid communication between canisterand direct inject cartridge.

Kit′ also includes a second valve member′ which is disposed between T-fittingand vacuum pump. Second valve member′ is adapted to threadably engage the T-fittingand provide fluid communication between vacuum pumpand T-fittingand thereby provide fluid communication between pumpand direct inject cartridge. A hoseis optionally provided between second valve member′ and vacuum pump. Second valve member′ further includes a valve actuator′ for selectively opening and closing the valve of second valve member′. Second valve member′ is adapted to provide selectively actuated fluid communication between direct inject cartridgeand pump. As discussed above, kit′ can also include filter. Kit′ can also optionally include a filter.

Referring to, the method of using kitto fill, or to refill, direct inject cartridgewill now be described. At step, canisteris attached to first valve member. As described above, canistercontains a selected refrigerant additive, preferably under negative pressure. First valve memberis confirmed closed, step, by ensuring that valve actuatoris in the closed position, as illustrated in. First valve memberis attached to the direct inject cartridge; and, second valve memberis also attached to direct inject cartridgeat step. At step, the second valve memberplaced in fluid communication with vacuum pump. While second valve membercould be connected directly to pump, optionally, filtercould be positioned between second valve memberand vacuum pump. Second valve membershould be confirmed to be in the open position at step.illustrates first valve memberbeing in the closed position and second valve memberbeing in the open position. It should be understood that so long as steps,,,andare performed, the sequence or order of performing these steps is not critical.

Once steps,,,andare performed, vacuum pumpis activated, step, and allowed to run for a selected period of time, step. The time for running vacuum pumpwill depend on the size of the direct inject cartridge, however, allowing vacuum pump to run at least ten seconds, in one exemplary embodiment, and for at least between ten seconds and thirty seconds in a further exemplary embodiment, should be sufficient. After this period of time, and while the vacuum pump is still running, second valve memberis rotated back to the closed position, step, as illustrated in, and, vacuum pumpis deactivated. The actuatorof first valve memberis then rotated to the open position, illustrated in, step, and direct inject cartridgeis allowed to fill with refrigerant additive. Once direct inject cartridgeis filled with refrigerant additive, actuatorof first valve memberis rotated to the closed position, step, and first valve memberand second valve memberare removed from direct inject cartridge, step.

It will be appreciated that while a technician could use the system of the present invention, including kit, and associated methodto fill used direct inject cartridgeswhile on a job site, a technician could also refill used and empty direct inject cartridgesin a workshop environment prior to going to a jobsite or upon returning from a jobsite. Alternatively, the technician could perform the second part of step, i.e., connecting second valve memberto direct inject cartridge, and perform steps,,, to a plurality of direct inject cartridges in one location. Then the technician could perform steps,, the first part of, and stepsand, to this plurality of previously evacuated direct inject cartridgesin a different location.

Further, the kitand associated methodalso provide flexibility and allow the technician to be prepared for a variety of scenarios. Rather than carrying a large variety of direct inject cartridges of various capacities and with various refrigerant additives, a technician could carry a plurality of empty direct inject cartridgesthat have already been evacuated by stepsthroughof method. The technician could also carry a plurality of canistersthat contain a variety of refrigerant additives. Once the technician has diagnosed the problem at the jobsite and identified the necessary refrigerant additive, the technician could then fill the evacuated direct inject cartridgeswith the appropriate refrigerant additive by attaching the appropriate canisterto the first valve memberand attaching the first valve memberto the direct inject cartridgeand executing stepsandof methodand removing the first valve memberfrom the direct inject cartridgeand the canister.

In a further exemplary embodiment, a kit, system, and method are provided for filling, or refilling, a syringe-style direct inject. As illustrated in, kitis provided for filling, or refilling syringe-style direct inject. It will be appreciated by those skilled in the art that syringe-style direct injecthas a first end, which in an exemplary embodiment is an externally threaded nozzle. A second end of syringe-style direct injectincludes and cooperates with an adapter cap. Adapter capincludes a cap memberthat is threadably engaged with the second end of syringe-style direct injectand an externally threaded self-sealing valve, that, in an exemplary embodiment is defined by a Schrader valve. While an exemplary embodiment utilizes a Schrader valve, those skilled in the art that other types of self-sealing valves could be utilized.

Syringe-style direct injectalso includes a cylindrical body. Disposed within cylindrical bodyis a plungerhaving at least one, and preferably two plunger sealing O-rings. Similar to cylindrical bodydescribed above, cylindrical bodyis adapted to contain a selected refrigerant gas additive. As discussed above, such refrigerant additives can include sealants, including conditioners for rubber components such as O-rings, lubricants, dyes, such as UV dyes used for leak detection, system enhancers for reducing energy use or improving heat transfer, drying agents, or a combination of two or more of such additives.

As stated above, canisteris provided and contains the refrigerant additive. In an exemplary embodiment, canistercontains only the refrigerant additive under at least a partial vacuum. Canisteris, in an exemplary embodiment, under negative pressure, i.e., at least a partial vacuum, to minimize the risk of exposing the refrigerant additive within canisterto atmospheric air which could oxidize or polymerize the refrigerant additive.

The kitfurther includes first valve member, which is disposed between canisterand syringe-style direct inject. First valve memberincludes a first endadapted to threadably engage and actuate self-sealing valve. As illustrated in, first valve memberserves as a can tap and includes a threaded collar, a pin, and a Teflon seal O-ringto ensure a proper seal with canister. Pinengages, and opens, the self-sealing valveof canister. As will be understood, pinis hollow and includes an orificewhich allows the contents of canisterto flow through pin, and first valve member. Unlike a conventional can tap, pinis fixed relative to the body of first valve member. Flow of the contents of canisteris selectively actuated by operation of valve actuator.

First valve memberfurther includes a second enddefined by an internally threaded valve chuck, in an exemplary embodiment, a Schrader valve chuck, and is adapted to threadably engage nozzleof syringe-style direct inject. First valve memberfurther includes a valve actuatorfor selectively opening and closing the valve of first valve member. While various types of valves could be utilized for first valve member, in an exemplary embodiment, first valve memberis a ball valve. First valve memberis adapted to provide selectively actuated fluid communication between canisterand syringe-style direct inject.

Kitalso includes a second valve memberwhich is disposed between syringe-style direct injectand a vacuum pump. Second valve memberincludes two, internally threaded valve chucks. In an exemplary embodiment, the valve chucks are defined by Schrader valve chucks. One such valve chuckengages threaded fittingof adapter cap. Second valve memberfurther includes a second valve chuckadapted to engage a vacuum port provided on vacuum pump. Second valve memberfurther includes a valve actuatorfor selectively opening and closing the valve of second valve member. While various types of valves could be utilized, in an exemplary embodiment, second valve memberis a ball valve. Second valve memberis adapted to provide selectively actuated fluid communication between syringe-style direct injectand vacuum pump.

As seen in, kitoptionally includes a filteras a safety precaution for protection of pump. In this regard, filteris adapted to catch any refrigerant additive that may flow through syringe-style direct injectinadvertently due to an accidental opening of valve actuatorwhile valve actuatoris either completely or partially opened.

In one aspect of the present invention, the disclosure provides a system that utilizes kitfor filling a new syringe-style direct injector refilling a used syringe-style direct inject. In accordance with the disclosed system, the components of kitare assembled together as described above, and the second valve memberis connected to the vacuum port provided on vacuum pump. Alternatively, second valve memberis connected to filter, which, in turn, is connected to pump. The components of kitare assembled and, in cooperation with pump, operate in functional cooperation to fill syringe-style direct injectas will be described hereinbelow.

It will be appreciated that syringe-style direct injectcould be filled according to the method illustrated in. However, syringe-style direct injectcould also be filled according to the steps of the following method. Referring to, the method of using kitto fill, or to refill, syringe-style direct injectwill now be described. At step, canisteris attached to first valve member. As described above, canistercontains a selected refrigerant additive, preferably under negative pressure. First valve memberis confirmed closed, step, by ensuring that valve actuatoris in the closed position, as illustrated in. First valve memberis attached to the syringe-style direct inject; and, second valve memberis also attached to syringe-style direct injectat step. At step, the second valve memberis placed in fluid communication with vacuum pump. While second valve membercould be connected directly to pump, optionally, filtercould be positioned between second valve memberand vacuum pump. First valve memberand second valve membershould be confirmed to be in the open position at step.illustrates first valve memberbeing in the closed position and second valve memberbeing in the open position. It should be understood that so long as steps,,,andare performed, the sequence or order of performing these steps is not critical.

Once steps,,,andare performed, vacuum pumpis activated, step, and allowed to run for a selected period of time, step. The time for running vacuum pumpwill depend on the size of the syringe-style direct inject, however, allowing vacuum pump to run at least ten seconds, in one exemplary embodiment, and for at least between ten seconds and thirty seconds in a further exemplary embodiment, should be sufficient. After this period of time, and while the vacuum pump is still running, the actuatorof first valve memberis then rotated to the open position, illustrated in, step and syringe-style direct injectis allowed to fill with refrigerant additive. Once syringe-style direct injectis filled with refrigerant additive, actuatorof first valve memberand actuatorof the second valve memberare both rotated to the closed position, step, and first valve memberand second valve memberare removed from syringe-style direct inject, step.

While the present invention has been illustrated by description of several embodiments and while the illustrative embodiments have been described in detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of applicant's general inventive concept.