Patent Description:
Air-operated pumps are used in a multitude of industries for moving materials from paints and stains to tomato and other food pastes.

<CIT> describes a technique for detecting and containing liquid leaks in a liquid pumping, gas-operated diaphragm pump, and for stopping the pump operation when such leaks occur. If there is a leak in such a pump, the exhaust air gets contaminated with the liquid. With this technique the pump exhaust gas is captured in a container where any liquid within the gas is separated and is allowed to accumulate at the container bottom. The level of liquid accumulated at the container bottom is sensed, and when it reaches a predetermined level, a signal is sent to a pneumatically operated shutoff valve to stop the pump operation by stopping the inflow of gas into the pump, or the outflow of liquid from the pump, or to stop the inflow of liquid into the pump. In addition, when the accumulated liquid reaches a predetermined level, a signal may be sent to a pneumatically operated warning device, turning it on.

<CIT> describes a security controller for diaphragm leakage liquid of an air diaphragm pump. The security controller comprises a rotary gasliquid separator, a mandril a gas source control valve, a gas discharge pipe, an overflow preventing device and a liquid seal device. The invention further provides a method for controlling the diaphragm leakage liquid of the air diaphragm pump through the security controller for the diaphragm liquid leakage of the air diaphragm pump. With the adoption of a mechanical ball float type pumping stop control method, air mixed with leaked liquid materials caused by a damaged diaphragm in the diaphragm pump is collected to a rotary air cylinder body, gas and liquid are separated by using a method of specific gravity, and a technology of pushing a float ball to close air source in the air diaphragm pump through aggregated leaked liquid is utilized. The security controller for the diaphragm leakage liquid of the air diaphragm pump can effectively overcome the maximum hazard which is likely to cause safety accidents by the fact that controlling methods of the traditional electric appliances are utilized in flammable and combustible environments in the chemical industry.

According to one aspect of the invention, an air-operated pump system has an air-operated pump and a leak detection and containment assembly. The air-operated pump includes a pump body, and a process liquid pathway defined at least in part by the pump body. An air pathway is defined at least in part by the pump body, wherein the process liquid pathway and air pathway are fluidly separated from one another within the pump body, and wherein air passing along the air pathway causes pumping of the process liquid along the process liquid pathway.

The leak detection and containment assembly are integrated with the pump body. The leak detection and containment assembly includes a process liquid sensor configured to sense process liquid leaked from the process liquid pathway into the air pathway and a shutoff valve communicatively coupled to the process liquid sensor. The shutoff valve is configured to close in response to the process liquid sensor detecting process fluid to contain the leaked process liquid within the pump body and the assembly. The leak detection and containment assembly is disposed along the air pathway and downstream from an air outlet of the pump body. The process liquid sensor is located below a bottom of a main air channel on the air pathway, whereby the process liquid sensor is out of a direct line of exhaust flow on the main air channel of the air pathway.

The process liquid sensor is a static sensor having all fixed components in response to air flow or process liquid moving past the process liquid sensor. Further, the process liquid sensor is located at the lowest point of the air pathway. The leak detection and containment assembly further includes a muffler disposed along the air pathway to abate the noise level of air exhausted from the pump body. The process liquid sensor is spaced along the air pathway from the muffler to reduce impact of muffler icing on the process liquid sensor.

The leak detection and containment assembly defines a linear section of the air pathway of the air-operated pump. The bottom of the main air channel is a lowest point of an inner diameter of the main air channel. A tip of the process liquid sensor is located about two inches below the bottom of the main air channel. The air-operated pump is a diaphragm pump, and the process liquid pathway and the air pathway are separated from one another by at least one movable diaphragm. The controller communicatively couples the shutoff valve and the process liquid sensor. The controller is configured to close the shutoff valve when process liquid is detected at the process liquid sensor.

According to another aspect of the invention, an air-operated diaphragm pump has a pump body with a process liquid inlet, a process liquid outlet, an air inlet and an air outlet. A process liquid pathway is defined, at least in part, by the pump body and extends at least from the process liquid inlet through the process liquid outlet. An air pathway is defined, at least in part, by the pump body and extending at least from the air inlet through the air outlet. One or more diaphragm members are disposed in the pump body and fluidly separating the process liquid pathway from the air pathway in the pump body. The one or more diaphragm members are configured for being driven by a supply of air directed along the air pathway to cause movement of a process liquid along the process liquid pathway.

A leak detection and containment muffler assembly is coupled to the air outlet. The leak detection and containment muffler assembly includes a process liquid sensor downstream of the air outlet along the air pathway. The process liquid sensor detects process liquid having leaked into the air pathway. A shutoff valve is communicatively coupled to the process liquid sensor and configured to be open in the absence of liquid. The shutoff valve closes the air pathway downstream of the air outlet upon detection of a process liquid leak into the air pathway at the process liquid sensor. The assembly includes a muffler for abating the noise level of air exhausted from the air outlet of the diaphragm pump. The process liquid sensor is located below the bottom of a main air channel on the air pathway, whereby the process liquid sensor is out of the direct line of exhaust flow on the main air channel of the air pathway.

The shutoff valve is disposed downstream of process liquid sensor along the air pathway. The process liquid sensor is a static sensor having all fixed components in response to air flow or process liquid moving past the process liquid sensor. The process liquid sensor is spaced upstream along the air pathway from the muffler to reduce impact of muffler icing on the process liquid sensor. The leak detection and containment muffler assembly defines a linear section of air pathway of the air-operated pump.

The air-operated diaphragm pump further includes a controller communicatively connecting the shutoff valve and the process liquid sensor, the controller configured to trigger the shutoff valve upon recognition of material leak by the process liquid sensor. The bottom of the main air channel is a lowest point of an inner diameter of the main air channel, where a tip of the process liquid sensor is located about two inches below the bottom of the main air channel.

According to another aspect of the invention, a leak detection and containment assembly provides an air pathway for exhaust of motive air from an air-operated pump, where the motive air drives movement of a process liquid through the air-operated pump. The leak detection and containment assembly includes a coupling element, a process liquid sensor, a shutoff valve, and a muffler. The coupling element allows for coupling the leak detection and containment assembly to a respective air-operated pump. The process liquid sensor detects the presence of process liquid in the air pathway. The shutoff valve is communicatively coupled to the process liquid sensor and configured to be open in the absence of liquid, closing the air pathway downstream of the process liquid sensor upon detection of the presence of the process liquid at the process liquid sensor. The muffler abates the noise level of air exhausted from the leak detection and containment assembly.

The coupling element is threaded to allow for threaded coupling to a respective air-operated pump. The process liquid sensor is a static sensor having all fixed components in response to air flow moving past the process liquid sensor. The leak detection and containment assembly further includes a controller communicatively coupling the shutoff valve and the process liquid sensor. The controller is configured to trigger the shutoff valve upon detection of the process liquid at the process liquid sensor. The process liquid sensor is located below a bottom of a main air channel on the air pathway. The process liquid sensor is out of a direct line of exhaust flow on the main air channel of the air pathway. The bottom of the main air channel is a lowest point of an inner diameter of the main air channel. A tip of the process liquid sensor is located about two inches below the bottom of the main air channel. The process liquid sensor is located at the lowest point of the air pathway.

These and other features of the present invention, and their advantages, are illustrated specifically in embodiments of the invention now to be described, by way of example, with reference to the accompanying diagrammatic drawings, in which:.

It should be noted that all the drawings are diagrammatic and not drawn to scale. Relative dimensions and proportions of parts of these figures have been shown exaggerated or reduced in size for the sake of clarity and convenience in the drawings. The same reference numbers are generally used to refer to corresponding or similar features in the different embodiments. Accordingly, the drawings and description are to be regarded as illustrative in nature and not as restrictive.

Accordingly, a value modified by a term or terms, such as "about", is not limited to the precise value specified. Range limitations may be combined and/or interchanged, and such ranges are identified and include all the sub-ranges stated herein unless context or language indicates otherwise. Other than in the operating examples or where otherwise indicated, all numbers or expressions referring to quantities of ingredients, reaction conditions and the like, used in the specification and the claims, are to be understood as modified in all instances by the term "about".

"Optional" or "optionally" means that the subsequently described event or circumstance may or may not occur, or that the subsequently identified material may or may not be present, and that the description includes instances where the event or circumstance occurs or where the material is present, and instances where the event or circumstance does not occur or the material is not present.

As used herein, the terms "comprises", "comprising", "includes", "including", "has", "having", or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article or apparatus that comprises a list of elements is not necessarily limited to only those elements, but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise.

A "processor", as used herein, processes signals and performs general computing and arithmetic functions. Signals processed by the processor can include digital signals, data signals, computer instructions, processor instructions, messages, a bit, a bit stream, or other means that can be received, transmitted and/or detected. Generally, the processor can be a variety of various processors including multiple single and multicore processors and co-processors and other multiple single and multicore processor and co-processor architectures. The processor can include various modules to execute various functions.

A "memory", as used herein can include volatile memory and/or nonvolatile memory. Non-volatile memory can include, for example, ROM (read only memory), PROM (programmable read only memory), EPROM (erasable PROM), and EEPROM (electrically erasable PROM). Volatile memory can include, for example, RAM (random access memory), synchronous RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), and direct RAM bus RAM (DRRAM). The memory can also include a disk. The memory can store an operating system that controls or allocates resources of a computing device. The memory can also store data for use by the processor.

A "disk", as used herein can be, for example, a magnetic disk drive, a solid state disk drive, a floppy disk drive, a tape drive, a Zip drive, a flash memory card, and/or a memory stick. Furthermore, the disk can be a CD-ROM (compact disk ROM), a CD recordable drive (CD-R drive), a CD rewritable drive (CD-RW drive), and/or a digital video ROM drive (DVD ROM). The disk can store an operating system and/or program that controls or allocates resources of a computing device.

Some portions of the detailed description that follows are presented in terms of algorithms and symbolic representations of operations on data bits within a computer memory. An algorithm is here, and generally, conceived to be a self-consistent sequence of steps (instructions) leading to a desired result. The steps are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical, magnetic or optical non-transitory signals capable of being stored, transferred, combined, compared and otherwise manipulated. It is convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like. Furthermore, it is also convenient at times, to refer to certain arrangements of steps requiring physical manipulations or transformation of physical quantities or representations of physical quantities as modules or code devices, without loss of generality.

However, all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise as apparent from the following discussion, it is appreciated that throughout the description, discussions utilizing terms such as "processing" or "computing" or "calculating" or "determining" or "displaying" or "determining" or "comparing" or the like, refer to the action and processes of a computer system, or similar electronic computing device (such as a specific computing machine), that manipulates and transforms data represented as physical (electronic) quantities within the computer system memories or registers or other such information storage, transmission or display devices.

Certain aspects of the embodiments described herein include process steps and instructions described herein in the form of an algorithm. It should be noted that the process steps and instructions of the embodiments could be embodied in software, firmware or hardware, and when embodied in software, could be downloaded to reside on and be operated from different platforms used by a variety of operating systems. The embodiments can also be in a computer program product which can be executed on a computing system.

The embodiments also relates to an apparatus for performing the operations herein. This apparatus can be specially constructed for the purposes, e.g., a specific computer, or it can comprise a general-purpose computer selectively activated or reconfigured by a computer program stored in the computer. Such a computer program can be stored in a non-transitory computer readable storage medium, such as, but is not limited to, any type of disk including floppy disks, optical disks, CD-ROMs, magnetic-optical disks, read-only memories (ROMs), random access memories (RAMs), EPROMs, EEPROMs, magnetic or optical cards, application specific integrated circuits (ASICs), or any type of media suitable for storing electronic instructions, and each electrically connected to a computer system bus. Furthermore, the computers referred to in the specification can include a single processor or can be architectures employing multiple processor designs for increased computing capability.

Various general-purpose systems can also be used with programs in accordance with the teachings herein, or it can prove convenient to construct more specialized apparatus to perform the method steps. The structure for a variety of these systems will appear from the description below. In addition, the embodiments are not described with reference to any particular programming language. It will be appreciated that a variety of programming languages can be used to implement the teachings of the embodiments as described herein, and any references below to specific languages are provided for disclosure of enablement and best mode of the embodiments.

In addition, the language used in the specification has been principally selected for readability and instructional purposes, and may not have been selected to delineate or circumscribe the inventive subject matter. Accordingly, the disclosure of the embodiments is intended to be illustrative, but not limiting, of the scope of the embodiments, which is set forth in the claims.

The principles of the present disclosure have general application to air-operated pumps for moving a process liquid, and particular application to a leak detection and containment assembly, such as for use as a component of an air-operated pump assembly. As used herein, process liquid may refer to a liquid, slurry, gelatinous substance, suspension, etc., examples of which may include paints, stains, gasoline, strong acids, strong bases, food pastes such as tomato paste, etc..

These pumps are driven by a gas, such as compressed air. Motion of the motive air through driving chambers of an air-operated pump causes the pump to then move a process liquid through the pump. Typical air driven pumps are utilized continuously for long periods, often for many millions of cycles, and can include numerous moving parts. Reliable and continuous transfer of the process liquid can be critical to the industrial or other processes in which the process liquids are used. A leak of air or process liquid between an air side of a pump diaphragm and a process liquid side of the pump diaphragm, which sides are intended to remain separated during use of the pump, can cause significant contamination and/or spill issues. This unwanted occurrence can result in lost process liquid, extended downtimes, and expensive cleanup procedures, among other disadvantages.

Turning first to <FIG>, an air-operated pump system <NUM> is shown, comprising an air-operated pump <NUM> with a leak detection and containment muffler assembly <NUM>. Air-operated pumps <NUM> generally include an air pathway separated from and provided for moving/pumping a process liquid along a process liquid pathway through the pump. The pump <NUM> includes a pump body <NUM>, which may be made of any suitable metal, polymer, combination thereof, etc., such as a chemically-resistant material. The pump body <NUM> includes base members <NUM> that may be secured to a surface for supporting the pump <NUM> during its use.

The depicted pump body <NUM> includes a process liquid inlet <NUM>, a process liquid outlet <NUM>, an air inlet <NUM> and an air outlet <NUM>. The air outlet <NUM> is sometimes also known as an exhaust.

A process liquid pathway <NUM> is defined at least in part by the pump body <NUM> and extends at least from the process liquid inlet <NUM> through the process liquid outlet <NUM>. An air pathway <NUM> is defined at least in part by the pump body <NUM> and extends at least from the air inlet <NUM> to the air outlet <NUM>. The air pathways <NUM> are illustrated in part in <FIG> and continues at <FIG>.

Generally, with reference to the depicted air-operated pump <NUM>, air passing into the air inlet <NUM> and to the air outlet <NUM> to be exhausted form the pump <NUM> provides a motive force for moving a process liquid through the pump <NUM>.

Air is received into air inlet <NUM> through the air intake system <NUM>. The air intake system <NUM> is comprised of a filter/regulator <NUM>, an air supply on/off valve <NUM>, a union <NUM>, a pressure gauge <NUM>, and a pressure release valve <NUM>. Motive air is received into the filter/regulator <NUM>, where the air is filtered and the pressure is adjusted to the user specifications. The motive air can be shop air and is generally provided by an air compressor that is connectable to the filter/regulator <NUM>. Downstream from the filter/regulator <NUM> is the air supply on/off valve <NUM>, which is threadably connected to the filter regulator <NUM> via a filter/regulator coupler <NUM>. In an embodiment, the air supply on/off valve <NUM> may be manually changed between the on and off positions. In other embodiments, the air supply on/off valve <NUM> may also be automated and/or electronically controllable, such as through controller <NUM>. Downstream from the air supply on/off valve <NUM> is a union <NUM>. The air supply on/off valve and union <NUM> are threadably coupled via a union coupler <NUM>. Also threadably connected to the union <NUM> is a pressure gauge <NUM> and a pressure release valve <NUM>. The union is threadably coupled to the air inlet <NUM> via an air inlet coupler <NUM>.

In an embodiment, motive air is received at the filter/regulator <NUM> travels through the air supply on/off valve <NUM> through the filter/regulator coupler <NUM>. The motive air is then received at the union <NUM> from the air supply on/off valve <NUM> through the union coupler <NUM>. The union <NUM> also have a pressure gauge <NUM> for monitoring the pressure within the air intake system <NUM> and received by the air inlet <NUM>. Further, the union <NUM> also has a pressure release valve <NUM> for releasing pressure from within the air intake system <NUM> and at the air inlet <NUM>. The motive air is then received at the air inlet <NUM> from the union <NUM> through the air inlet coupler <NUM>.

The motive air received at air inlet <NUM> is passed through a series of chambers (not specifically shown) in the pump body <NUM> to drive movement of a valve <NUM> (location generally shown) connected to a central rod <NUM>. Movement of the valve <NUM> causes movement of at least one moveable member <NUM>, such as a diaphragm, that is coupled to the central rod <NUM>.

In pump <NUM>, diaphragms <NUM> may be used. In an embodiment of pump <NUM> shown, a pair of vertically spaced apart diaphragms <NUM> may be used, located in air sides <NUM> of respective diaphragm chambers <NUM> of the pump body <NUM>. Accordingly, the pump <NUM> may also include a pair of air pathways <NUM> and a pair of process liquid pathways <NUM>, which alternate in operation as will be explained further.

In other embodiments, the diaphragms <NUM> may be otherwise located, and/or any suitable number of diaphragms <NUM> may be used. Additionally or alternatively, the pump <NUM> may have an alternative construction that may include fewer or additional portions of each of the air pathway <NUM> and the process liquid pathway <NUM>.

Although pump <NUM> is depicted as an air-operated diaphragm pump, it is contemplated that pump <NUM> can be any type of air assisted (pneumatic) pump having a failure mode where process liquid can exit the process liquid pathway <NUM> and enter the air pathway <NUM>. Stated alternatively, air-operated pump <NUM> can be any type of pump having a process liquid pathway <NUM> and air pathway <NUM> that are fluidly separated from one another within the pump body <NUM>; wherein air passing along the air pathway <NUM> causes pumping of the process liquid along the process liquid pathway <NUM>.

In an air-operated diaphragm pump, when air pressure is applied to the pump <NUM> via the air pathway <NUM> the valve <NUM> moves up and down, causing air pressure to divert to an air side <NUM> of the respective diaphragm chamber <NUM>. Due to the movement of the valve <NUM>, as air is diverted to one diaphragm chamber <NUM>, air in the opposite chamber <NUM> is exhausted out of the air outlet <NUM>. This motive air process constantly alternates between the diaphragm chambers <NUM> (and specifically between the air sides <NUM> of the chambers <NUM>) to create a continuous cycle. The motive/driving air typically is exhausted into the environment in the use of air-operated pumps.

Movement of the diaphragms <NUM> within the chambers <NUM> causes pumping of the process liquid in a similar manner. One diaphragm <NUM> creates suction into a process liquid side <NUM> of a respective diaphragm chamber <NUM>, drawing process liquid from the process liquid inlet <NUM>. The other diaphragm <NUM> expels process liquid from the opposite and respective diaphragm chamber <NUM> to the process liquid outlet <NUM>. This process cycles and continues concurrently with movement of the motive air, thus pumping process liquid.

In addition to pumping, the diaphragms <NUM> also serve as barriers between the air side/air pathway <NUM> and process liquid side/process liquid pathway <NUM> of the pump body <NUM>. Often, strokes are continuously counted and diaphragms <NUM> and other seals replaced, such as on a schedule, due to wear of the diaphragms <NUM> and other seals.

Even in view of such a maintenance/changeover schedule, a leak may occur between the air pathway <NUM> and process liquid pathway <NUM> of the pump <NUM>. The leak may be caused by a worn or blow seal or diaphragm <NUM>, tension or stress in the pump body <NUM> such as related to installation, and/or improperly tightened fasteners <NUM> coupling together portions of the pump body <NUM>, such as portions defining the diaphragm chambers <NUM>.

Regardless of the root cause, process liquid may begin to leak into the air pathway <NUM>. Absent a preventive measure, the leaked process liquid will be pumped out of the air outlet <NUM> with the exhaust air and into the environment disposed about the pump <NUM>. The spill/leak can cause costly and extensive cleanup operations, costly downtimes for pumping, and/or loss of process liquid, none of which is ideal. Further, a leak of the process liquid may also pose a danger to workers in the spill/lead area, such as when the process liquid is a hazardous chemical.

To remedy this concern, the pump <NUM> may include a leak detection and containment assembly <NUM>, such as shown schematically at <FIG>. The leak detection and containment assembly <NUM>, also herein referred to as a leak detection and containment muffler assembly <NUM> when including a muffler, is integrated with the pump body <NUM>.

Turning to <FIG> and <FIG>, the leak detection and containment assembly <NUM> extends between a coupling element <NUM> at a proximal end <NUM> of the assembly and a muffler <NUM> at a distal end <NUM> of the assembly <NUM>. Therebetween are disposed a shutoff valve <NUM> and a process liquid sensor <NUM>. While each of the elements of the coupling element <NUM>, muffler <NUM>, shutoff valve <NUM>, and process liquid sensor <NUM> are depicted as being coupled to one another via threads, other suitable methods may be used where suitable, such as adhesive, welding, etc., depending on materials used.

Aspects of the assembly may be composed of metal, polymer, chemical resistant materials, etc., where suitable.

Generally the assembly <NUM> defines a linear section of air pathway of the air-operated pump <NUM>, when integrated with the body <NUM>, to allow for ease of exhaust and detection of a leaked process liquid. For example, the assembly <NUM> at least provides a linear pathway between the coupling element <NUM> and muffler <NUM>, and the illustrated assembly includes the process liquid sensor <NUM>, muffler <NUM>, and shutoff valve <NUM> oriented relative one another to define a linear pathway between the coupling element <NUM> and muffler <NUM>. Where suitable, the pathway through the assembly <NUM> may be otherwise oriented.

Integration with the pump body <NUM> may be by way of any suitable attachment, such as fasteners, threads, welding, etc. Preferably, the assembly <NUM> may be coupled to the pump body <NUM> via interlocking threads at each of the pump body <NUM> and assembly <NUM>. Typical pump bodies <NUM> include threads at the exhaust or air outlet <NUM>, such as for attachment of a muffler. The depicted assembly <NUM> includes the coupling element <NUM> having threads for coupling to the air outlet <NUM>. Where the threads are inappropriately sized, reducing or enlarging components may be used, threaded to the proximal end <NUM> of the assembly <NUM> to allow for retrofit to previously existing or used pumps <NUM>/pump bodies <NUM>. For example, the depicted coupling element <NUM> may be replaced with the coupling elements <NUM> and <NUM> shown in <FIG> to allow for pipe size reduction at the proximal end <NUM>.

Turning again to <FIG>, opposite the coupling element <NUM> is disposed the muffler <NUM>. The muffler <NUM> typically includes a noise abating material, element, or tortuous pathways to reduce the decibel level created by the motive air as it is exhausted from the pump <NUM>/air pathway <NUM>.

Disposed along the assembly <NUM> upstream of muffler <NUM> is the process liquid sensor <NUM>. As used herein, the upstream direction refers to a direction opposite a downstream direction, and more particularly, taken from the distal end <NUM> towards the proximal end <NUM>, opposite a normal direction of air flow along the air pathway <NUM>. The downstream direction refers to a direction taken from the proximal end <NUM> towards the distal end <NUM> in the normal direction of air flow along the air pathway <NUM>.

The process liquid sensor <NUM> is configured to sense process liquid having leaked from the process liquid pathway <NUM> into the air pathway <NUM>. To provide for rapid sensing and reduced maintenance on the assembly <NUM>, the process liquid sensor <NUM> may be a static sensor, such as a conductance or capacitance sensor, having all fixed components in response to air flow moving past the process liquid sensor <NUM>. Thus, rather than requiring buildup of liquid within a reservoir, or to move a float mechanism, for instance, the process liquid sensor <NUM> may more rapidly identify an unintended contaminant within the air pathway <NUM>.

Process liquid sensor <NUM> has a sensing element <NUM> having a tip <NUM>. The sensing element <NUM> is the portion of process liquid sensor <NUM> that will result in a change of the output of process liquid sensor <NUM>, when contacted with process liquid. Stated alternatively, a change in the output of process liquid sensor <NUM> occurs when process liquid comes into contact with sensing element <NUM>.

Further, in some embodiments, the process liquid sensor <NUM> may be located out of the direct line of exhaust flow on the main air channel <NUM> of air pathway <NUM> of leak detection and containment assembly <NUM>. In an embodiment, the main air channel <NUM> can be the most direct route for exhaust flow from the air outlet <NUM> to the distal end <NUM>. Stated alternatively, the main air channel <NUM> can be the most direct route for exhaust flow from the air outlet <NUM> to the muffler <NUM>. Additionally, in some embodiments, the process liquid sensor <NUM> may also be located at the low point of the leak detection and containment assembly <NUM>. In some embodiments, the process liquid sensor <NUM> may be located at the lowest point of the air pathway <NUM> downstream from the air outlet <NUM>. In some embodiments, the tip <NUM> of the sensing element <NUM> of the process liquid sensor <NUM> may be located below a bottom <NUM> of the main air channel <NUM>. In another embodiment, the tip <NUM> of the process liquid sensor <NUM> can be located between about. <NUM> inches and <NUM> inches below the bottom <NUM> of the main air channel <NUM>. In a further embodiment, the tip <NUM> of the process liquid sensor <NUM> can be located between about <NUM> inch and <NUM> inches below the bottom <NUM> of the main air channel <NUM>.

The tip <NUM> is the portion of the sensing element <NUM> of the process liquid sensor <NUM> that is located the closest to bottom <NUM> of the main air channel <NUM>. Depending on the geometry of the sensing element <NUM>, the tip <NUM> can range from a small portion of the sensing element <NUM> to the entirety of sensing element <NUM>. In an embodiment, the bottom <NUM> of the main air channel <NUM> may be defined as the lowest point of the inner diameter <NUM> of the main air channel <NUM>. In another embodiment, the bottom <NUM> of the main air channel <NUM> may be defined as the lowest point of the inner diameter <NUM> of the T-element <NUM> on the main air channel <NUM>. In an embodiment, the tip <NUM> of the process liquid sensor <NUM> can be located about two inches below the bottom <NUM> of the main air channel <NUM>. In an embodiment, the tip <NUM> of the process liquid sensor <NUM> can be located less than about four inches below the bottom <NUM> of the main air channel <NUM>.

The position of the process liquid sensor <NUM> below the direct line of exhaust flow on the main air channel <NUM> mitigates false positives indicating a process liquid leak, such as due to an increase in the moisture content of the air travelling through air pathway <NUM>. Thus, when shop air is used to power pump <NUM>, the moisture in the shop air will pass through air pathway <NUM> and pass over the sensor <NUM> without contacting the sensing element <NUM>, thereby mitigating the occurrence of false positives for process liquid leaks. However, process liquid that travels past a failed diaphragm <NUM> will still contact the sensing element <NUM> and be accurately sensed by process liquid sensor <NUM>.

The process liquid sensor <NUM> may be chosen or configured to specifically sense the particular process liquid being pumped, such as conductive liquid or non-conductive liquid. For example, aspects of the sensor may be adjusted, including, but not limited to sensitivity, power level, etc..

The process liquid sensor <NUM> is depicted as a conductance or capacitance sensor for detecting a change in conductance or capacitance in the flow along the air pathway <NUM>, such as a conductive liquid sensor. Further, process liquid sensor <NUM> may be a non-conductive liquid sensor, such as, but not limited to, photoelectric level sensor type VP, unmodulated VP03EP, manufactured by Carlo Gavazzi Automation of Lainate, Italy, also known as a dome sensor or optical liquid sensor. A dome sensor work on the principle of total internal reflection, where an LED and photo-transistor are housed in a head (tip) of the dome. When no liquid is present, light from the LED is reflected internally from the dome to the photo-transistor. When liquid is covering the dome, the effective refractive index at the dome-liquid boundary changes, allowing some light from the LED to escape. Thus the amount of light received by the photo-transistor is reduced and the output switches, indicating the presence of liquid.

In some embodiments, the non-conductive liquid sensor can be used to sense both non-conductive liquids, as well as conductive liquids. In some embodiments, the process liquid sensor <NUM> may include two or more cooperating sensors which act as process liquid sensor <NUM>. In some embodiments, the process liquid sensor <NUM> may include an infrared sensor, moisture sensor, conductive liquid sensor, non-conductive liquid sensor, or other suitable sensor for detecting presence of process liquid in the air pathway <NUM> downstream of the air outlet <NUM>. In an embodiment, the process liquid sensor <NUM> may be configured to sense liquid having a conductivity of at least that of Dasani® bottled water, such as about <NUM>µΩ/cm<NUM>.

Positioning of the assembly <NUM> along the air pathway <NUM> downstream of the body <NUM> permits the air exhaust to propel any leaked process liquid downstream from the body <NUM> and onto the process liquid sensor <NUM>, when the shutoff valve <NUM> is open, thereby helping to detect a leak faster. To achieve sensing of the air pathway <NUM>, the process liquid sensor <NUM> is positioned downstream of the air outlet <NUM>, when the assembly <NUM> is integrated with the pump body <NUM>.

As depicted, the process liquid sensor <NUM> is disposed along the assembly <NUM> between the coupling element <NUM> and the shutoff valve <NUM>. In some embodiments, shutoff valve <NUM> may be a solenoid valve. Positioning of the process liquid sensor <NUM> upstream of the shutoff valve <NUM> may allow for containment of a majority, or even all, of the process liquid leaked into the assembly <NUM>, such as where the process liquid sensor <NUM> rapidly detects the process liquid and allows for closing of the shutoff valve <NUM>. The process liquid sensor <NUM> also is disposed along the air pathway <NUM> or assembly <NUM> spaced from the muffler <NUM>, which can reduce the impact of muffler icing causing a negative contaminant reading on the process liquid sensor <NUM>.

The process liquid sensor <NUM> is removably coupled, such as threaded, to the remainder of the assembly <NUM>, such as to allow for maintenance or cleaning of the process liquid sensor <NUM>. As depicted, the process liquid sensor <NUM> is a component of a process liquid sensor subassembly <NUM> disposed along the body of the assembly <NUM>. The depicted process liquid sensor subassembly <NUM> includes the process liquid sensor <NUM>, a bushing <NUM>, and a T-element <NUM>. The process liquid sensor <NUM> is coupled to the bushing <NUM>, which is coupled to the T-element <NUM>, where the T-element <NUM> is coupled in line with the coupling element <NUM> and shutoff valve <NUM> along the assembly <NUM>. In other embodiments, another suitable arrangement of components may be used, the bushing <NUM> may be omitted where suitable, and/or any of the components of the process liquid sensor subassembly <NUM> may be integral with one another. Further, in some embodiments, T-element <NUM> and coupler <NUM> may be replaced with a bung on coupling element <NUM>, whereby the T-element <NUM> may be formed by the bung on coupling element <NUM>.

The shutoff valve <NUM> is disposed along the assembly <NUM> between the muffler <NUM> and the process liquid sensor <NUM>. The depicted shutoff valve <NUM> is shown as being threadedly coupled to the T-element <NUM> via a coupler <NUM>. The threading allows for maintenance and cleaning of various components/aspects of the leak detection and containment assembly <NUM>.

In some embodiments, another suitable connection may be used and/or any of the shutoff valve <NUM>, muffler <NUM> and process liquid sensor subassembly <NUM> may be permanently coupled or integral with one another along the assembly <NUM>. In some embodiments, the process liquid sensor <NUM> instead may be disposed between the muffler <NUM> and the shutoff valve <NUM>, where suitable.

The shutoff valve <NUM> is communicatively coupled to the process liquid sensor <NUM> and is configured to close in response to the process liquid sensor <NUM> sensing a process liquid or contaminant, to thereby contain the leaked process liquid or contaminant within the pump body <NUM> and the assembly <NUM>. The shutoff valve <NUM> is illustrated as a motor-rotated ball valve, including a motor <NUM>. Another type of shutoff valve may be used in other embodiments, such as a solenoid-activated knife-valve.

Referring now to <FIG> and <FIG>, the assembly <NUM> further includes a controller <NUM> communicatively coupling the shutoff valve <NUM> and the process liquid sensor <NUM>. The controller <NUM> has a power supply <NUM>. The controller <NUM> is generally configured to trigger the shutoff valve <NUM> upon the detection of process liquid by the process liquid sensor <NUM>. In some embodiments, the controller <NUM> may be integrated with either of the process liquid sensor subassembly <NUM> or the shutoff valve <NUM>. In some embodiments, the controller may be omitted and each of the shutoff valve <NUM> and process liquid sensor <NUM> may communicate directly with one another or with an external controller, to allow for triggering of the shutoff valve <NUM>.

As shown at least partially in <FIG>, <FIG> and <FIG>, each of the shutoff valve <NUM> and the process liquid sensor <NUM> include wiring <NUM> and <NUM>, respectively, extending therefrom for communicating with the controller <NUM>, thus communicatively coupling the shutoff valve <NUM> and the process liquid sensor <NUM>. In other embodiments, communication between any of the shutoff valve <NUM>, the process liquid sensor <NUM> and the controller <NUM> may be wireless or wired, and signals may be sent such as by way of LAN, WAN, Bluetooth®, Zigbee®, cellular, token ring, WiFi, etc..

Inclusion of the controller <NUM> allows for adjustment of the response between the process liquid sensor <NUM> and the shutoff valve <NUM>. For example, sensitivity or power setting of the process liquid sensor may be adjusted according to the process liquid and composition of the compressed air used.

The controller <NUM> may include one or more processors, storage, or memory for controlling the process liquid sensor <NUM> and the shutoff valve <NUM>. Accordingly, aspects described in the present disclosure may be embodied in any one or more of a system including hardware and/or software, software apart from hardware, or a method.

Each of the process liquid sensor <NUM> and the shutoff valve <NUM> may be powered by the power supply <NUM> coupled to the controller <NUM>, or may be separately powered by any suitable source.

In use, when the process liquid sensor <NUM> senses a fluid (process liquid), a signal is sent directly or indirectly to the shutoff valve <NUM>, triggering closing of the shutoff valve <NUM>. This closing of the shutoff valve <NUM> stops the flow of compressed air out of pump <NUM>, thereby preventing the pump <NUM> from operating and preventing process liquid from escaping out of containment assembly <NUM>, such as through the muffler <NUM>. In some embodiments, the process liquid sensor <NUM> also may be communicatively connected to an air compressor, which produces the compressed air depicted as driving pump <NUM>. In this way, the supply of compressed air to pump <NUM> may be shutdown such as to prevent buildup of pressure in the pump <NUM> that will not be exhausted. In other embodiments, the pump <NUM> may be configured to shutdown in response to sensing of failed exhausting of the compressed air.

Use of the leak detection and containment assembly <NUM> in conjunction with the pump body <NUM> allows for containment of process liquid in the unwanted scenario of a leak between the compressed air and process liquid sides of the pump body <NUM>. The assembly <NUM> according to the disclosure allows for retrofit to existing units. Other benefits include reduction of effect of icing of the muffler <NUM> in view of spacing of the process liquid sensor <NUM> from the muffler <NUM> and also rapid sensing in view of lack of requirement for buildup of liquid within a reservoir, or to move a float mechanism, which also may ice and require additional maintenance.

In summary, an air-operated pump <NUM> includes a pump body <NUM>, a process liquid pathway <NUM> defined at least in part by the pump body <NUM>, and an air pathway <NUM> defined at least in part by the pump body <NUM>, wherein the process liquid pathway <NUM> and air pathway <NUM> are separated from one another within the pump body <NUM> by diaphragm <NUM>. The pump <NUM> further includes a leak detection and containment assembly <NUM> integrated with the pump body <NUM> and having a process liquid sensor <NUM> configured to sense process liquid leaked from the process liquid pathway <NUM> into the air pathway <NUM>, and a shutoff valve <NUM> communicatively coupled to the process liquid sensor <NUM> and configured to close in response to the process liquid sensor <NUM> sensing a process liquid leak to contain the leaked process liquid within the pump body <NUM> and the assembly <NUM>. The leak detection and containment assembly <NUM> is disposed along the air pathway <NUM> permitting air exhaust from the body <NUM> to and flow through the shutoff valve <NUM> when open prior to exiting at the muffler <NUM>.

<FIG> is a flowchart illustrating a method <NUM> of operating an air-operated diagraph pump system with a leak detection and containment muffler assembly <NUM>. In block <NUM>, an air operated pump system <NUM> with an air-operated pump <NUM> and a leak detection and containment muffler assembly <NUM> comprising a controller <NUM>, process liquid sensor <NUM>, and a shutoff valve <NUM> are provided.

In block <NUM>, the controller <NUM> is connected to the process liquid sensor <NUM> and the shutoff valve <NUM>. In block <NUM>, an output from the process liquid sensor <NUM> is obtained by the controller <NUM>. In block <NUM>, the controller compares the output obtained from the process liquid sensor <NUM> to a predetermined output threshold indicating the presence of process liquid at the process liquid sensor <NUM>.

In an embodiment, the predetermined threshold can be a predetermined conductivity value and the output of the process liquid sensor <NUM> can be the conductivity value measured at the sensing element <NUM> of the conductivity sensor. The presence of process liquid may be indicated at the process liquid sensor <NUM>, when the conductivity value measured at the sensing element <NUM> is greater than the predetermined conductivity value.

In another embodiment, the predetermined threshold can be a predetermined voltage and the output of the process liquid sensor <NUM> can be a voltage that changes based on the presence of process liquid at the sensing element <NUM>. In an embodiment where the voltage output of the process liquid sensor <NUM> decreases, when process liquid is present at the sensing element <NUM>; the presence of process liquid at the process liquid sensor <NUM> may be indicated, when the voltage output of the process liquid sensor <NUM> is lower than the predetermined voltage. Stated alternatively, the detection of process liquid by the process liquid sensor <NUM> may be indicated, when the voltage output of the process liquid sensor <NUM> is lower than the predetermined voltage.

Further, in an embodiment where the voltage output of the process liquid sensor <NUM> increases, when process liquid is present at the sensing element <NUM>; the presence of process liquid at the process liquid sensor <NUM> may be indicated, when the voltage output of the process liquid sensor <NUM> is greater than the predetermined voltage. Stated alternatively, the detection of process liquid by the process liquid sensor <NUM> may be indicated, when the voltage output of the process liquid sensor <NUM> is higher than the predetermined voltage.

In block <NUM>, the method proceeds to block <NUM>, when the comparison by the controller <NUM> indicates that process liquid is present at the process liquid sensor <NUM>. Otherwise, the method proceeds to block <NUM>, when the comparison by the controller <NUM> does not indicate the presence of process liquid at the process liquid sensor <NUM>.

In block <NUM>, the controller <NUM> closes the shutoff valve <NUM> by sending a close command to the shutoff valve <NUM>, thereby shutting down pump <NUM> and preventing process liquid from escaping from air pathway <NUM>, such as through the muffler <NUM>.

<FIG> is a flowchart illustrating a method <NUM> of operating a leak detection and containment muffler assembly <NUM> for an air-operated pump <NUM>. The leak detection and containment muffler assembly <NUM> comprising a controller <NUM>, process liquid sensor <NUM> and shutoff valve <NUM>. In block <NUM>, a leak detection and containment muffler assembly <NUM> is provided and fitted to an air-operated pump <NUM>. The leak detection and containment muffler assembly <NUM> comprises a controller <NUM>, process liquid sensor <NUM>, and a shutoff valve <NUM>.

In block <NUM>, the controller <NUM> is connected to the process liquid sensor <NUM> and the shutoff valve <NUM>. In block <NUM>, an output from the process liquid sensor <NUM> is obtained by the controller <NUM>. In block <NUM>, the controller compares the output obtained by from the process liquid sensor <NUM> to a predetermined output threshold indicating the presence of process liquid at the process liquid sensor <NUM>.

Claim 1:
A leak detection and containment assembly (<NUM>) to provide an air pathway (<NUM>) for exhaust of motive air from an air-operated pump (<NUM>), the motive air for driving movement of a process liquid through the air-operated pump, the leak detection and containment assembly comprising:
a coupling element (<NUM>);
a process liquid sensor (<NUM>);
a shutoff valve (<NUM>) communicatively coupled to the process liquid sensor and configured to be closed, closing the air pathway downstream of the process liquid sensor upon detection of the presence of the process liquid at the process liquid sensor; and
a muffler (<NUM>); characterized in that
the leak detection and containment assembly (<NUM>) defines a linear section of air pathway of the air-operated pump (<NUM>) between the coupling element (<NUM>) and the muffler (<NUM>).