Pumping of collected liquids in systems

A system includes at least one fluid volume in which pressure varies, a retention volume for collecting a liquid used in operating the system; and a pump device in fluid connection with the retention volume and in operative connection with the fluid volume. The pump device includes a housing, a movable pressurizing mechanism within the housing and in fluid connection with the fluid volume, a biasing mechanism in operative connection with the pressurizing mechanism to bias the pressurizing mechanism in a first direction, and a pump volume within the housing. The volume of the pump volume is defined by a position of the pressurizing mechanism, wherein the position of the pressurizing mechanism is controlled by pressure within the fluid volume and the biasing mechanism. The pump device further includes an inlet port in fluid connection with the pump volume and an outlet port in fluid connection with the pump volume.

BACKGROUND OF THE INVENTION

The following information is provided to assist the reader in understanding technologies disclosed below and the environment in which such technologies may typically be used. The terms used herein are not intended to be limited to any particular narrow interpretation unless clearly stated otherwise in this document. References set forth herein may facilitate understanding of the technologies or the background thereof. The disclosure of all references cited herein are incorporated by reference.

In many types of systems, liquids are used that may be dripped, spilled, leaked or otherwise freed from containment during operation of the system. Such liquids include, for example, lubricants, coolants etc., which are used in many systems (for example, machining systems, grinding systems etc.). In current processes, a container such as a pan is provided to collect such fluids. Typically, the fluid is controlled or recovered by manually emptying the collection pan on a periodic basis.

SUMMARY OF THE INVENTION

In one aspect, a system includes at least one fluid volume in which pressure varies, a retention volume for collecting a liquid used in operating the system; and a pump device in fluid connection with the retention volume and in operative connection with the fluid volume. The pump device includes a housing, a movable pressurizing mechanism within the housing and in fluid connection with the fluid volume, a biasing mechanism in operative connection with the pressurizing mechanism to bias the pressurizing mechanism in a first direction, and a pump volume within the housing. The volume of the pump volume is defined by a position of the pressurizing mechanism, wherein the position of the pressurizing mechanism is controlled by pressure within the fluid volume and the biasing mechanism. The pump device further includes an inlet port in fluid connection with the pump volume and an outlet port in fluid connection with the pump volume. The pump device may further include a first check valve in operative connection with the inlet port and a second check valve in fluid connection with the outlet port. The pressurizing mechanism may, for example, be in fluid connection with the fluid volume via a closed loop.

In a number of embodiments, the pressurizing mechanism is a piston. The piston may, for example, be reciprocally movable within a cylinder within the housing of the pump. The system may further include at least one seal to form a sealed connection between the piston and the cylinder. The biasing mechanism may, for example, include a spring and/or other resilient biasing member(s).

In a number of embodiments, the biasing mechanism is in operative connection with a first side of the pressurizing mechanism and the fluid volume is in operative connection with a second side of the pressurizing mechanism. Movement of the pressurizing mechanism in the first direction causes the pump volume to increase and liquid from the retention volume to be drawn into the pump volume, and movement of the pressurizing mechanism in a second direction, generally opposite the first direction, causes the pump volume to decrease and liquid to be pumped from the pump volume through the outlet port.

In another aspect, a method of recovering a liquid used in a system, wherein the system includes a fluid volume in which pressure is varied and a retention volume for collecting the liquid, includes placing a pump device in fluid connection with the retention volume. The pump device includes a housing; a movable pressurizing mechanism within the housing and in fluid connection with the fluid volume, a biasing mechanism in operative connection with the pressurizing mechanism to bias the pressurizing mechanism in a first direction, a pump volume within the housing, the volume of the pump volume being defined by a position of the pressurizing mechanism; an inlet port in fluid connection with the pump volume; and an outlet port in fluid connection with the pump volume. The method further includes placing the pressurizing mechanism in operative connection with the fluid volume so that the position of the pressurizing mechanism is controlled by pressure within the fluid volume and the biasing mechanism. The pump device may further include a first check valve in operative connection with the inlet port and a second check valve in fluid connection with the outlet port. As described above, the pressurizing mechanism may, for example, be in fluid connection with the fluid volume via a closed loop.

In a number of embodiments of methods hereof, the pressurizing mechanism is a piston. The piston may, for example, be reciprocally movable within a cylinder within the housing of the pump. In a number of embodiments, the pump device further includes at least one seal to form a sealed connection between the piston and the cylinder. The biasing mechanism may, for example, include a spring and/or other resilient biasing member(s).

As described above, in a number of embodiments, the biasing mechanism is in operative connection with a first side of the pressurizing mechanism and the fluid volume is in operative connection with a second side of the pressurizing mechanism. Movement of the pressurizing mechanism in the first direction causes the pump volume to increase and liquid from the retention volume to be drawn into the pump volume, and movement of the pressurizing mechanism in a second direction, generally opposite the first direction, causes the pump volume to decrease and liquid to be pumped from the pump volume through the outlet port.

In a number of embodiments, the liquid is pumped by the pump device to be recycled for use in the system or another system. The liquid may, for example, include a lubricant. In other embodiments, the liquid is pumped by the pump device to be discarded as waste.

In a further aspect, a pump device powerable by changes in pressure in a fluid volume of a system, includes a housing, a movable pressurizing mechanism within the housing, a biasing mechanism in operative connection with the pressurizing mechanism to bias the pressurizing mechanism in a first direction, a fluid connection in operative connection with the pressurizing mechanism to place the pressurizing mechanism in operative connection with the fluid volume of the system, a pump volume within the housing, wherein the volume of the pump volume is defined by a position pressurizing mechanism wherein the position of the pressurizing mechanism is controlled by pressure within the fluid line and the biasing mechanism, an inlet port in fluid connection with the pump volume, and an outlet port in fluid connection with the pump volume. The pump device may, for example, further include a first check valve in operative connection with the inlet port and a second check valve in fluid connection with the outlet port. The pressurizing mechanism may, for example, be in fluid connection with the fluid volume via a closed loop.

In a number of embodiments, the pressurizing mechanism is a piston. The piston may, for example, be reciprocally movable within a cylinder within the housing of the pump. The pump may, for example, further include at least one seal to form a sealed connection between the piston and the cylinder. The biasing mechanism may, for example, include a spring and/or other resilient member(s).

In a number of embodiments, the biasing mechanism is in operative connection with a first side of the pressurizing mechanism and the fluid volume is in operative connection with a second side of the pressurizing mechanism. Movement of the pressurizing mechanism in the first direction causes the pump volume to increase and liquid from a liquid source to be drawn into the pump volume. Movement of the pressurizing mechanism in a second direction, generally opposite the first direction, causes the pump volume to decrease and liquid to be pumped from the pump volume through the outlet port.

The present invention, along with the attributes and attendant advantages thereof, will best be appreciated and understood in view of the following detailed description taken in conjunction with the accompanying drawings.

DETAILED DESCRIPTION OF THE INVENTION

As used herein and in the appended claims, the singular forms “a,” “an”, and “the” include plural references unless the context clearly dictates otherwise. Thus, for example, reference to “a piston” includes a plurality of such pistons and equivalents thereof known to those skilled in the art, and so forth, and reference to “the piston” is a reference to one or more such pistons and equivalents thereof known to those skilled in the art, and so forth.

In a number of embodiments, pumping devices, systems and/or methods hereof enable, for example, recovery of (that is, controlling the location of, reclamation of and/or recycling of) amounts of a liquid from a pan, tank or other container in a system in which “freeing”, “dripping” or “leaking” of the liquid occurs so that the liquid may, for example, be recovered. In a number of embodiments, the liquid is reclaimed and/or recycled for its original intended use. In a number of representative embodiments hereof, devices, systems and/or methods hereof are, for example, used to provide intermittent lubrication by recycling a lubricant liquid that has dripped or leaked into a collection container or pan. In other embodiments, the liquid may be transported as waste to, for example, a container or reservoir.

In a number of such embodiments, pressure changes caused, for example, by changes in an operational state of a system (in connection with which a pump device or devices hereof are operating) are used to power the pumping device(s). For example, each time a certain state change (for example, starting, stopping, an on/off actuation, a mode change etc.) occurs in a pressurizing or pressurized system (for example, including a system pump) of a device or system in connection with which a pump device or system hereof is used, the associated pressure change may be used to cause a volume of liquid to be pumped from, for example, a retention volume such as a collection pan or other container to any part of the device or system or to an ancillary device or system. No external mechanical linkages (that is, bodies or members to manage force and movement) are required to be connected to the pumping devices or systems hereof. Likewise, no electrical or other external power connections are required. All power used to drive the pump devices hereof is obtained from pressure changes occurring in the normal operation of the system(s) to which the pump devices hereof are operatively connected.

FIGS. 1 through 4Billustrate a representative embodiment of a pumping device or system100hereof positioned within a coolant, lubrication or other collected liquid pan12of a system10. System10includes a pressurized or pressurizing system14which, may, for example, include one or more pumps and pressurized fluid volumes14a(for example, a fluid line). For example, pressurized system14may, for example, be a coolant liquid system and system10may, for example, be a machining or grinding system. In the illustrated embodiment, pumping device100includes a pump housing110in which a movable pressurizing mechanism such as a piston120is movably positioned. Pressurizing mechanisms other than a piston (for example, a diaphragm or bladder) may be used. Piston120may, for example, include one or more seals to form a sealing engagement with a cylinder130in which piston120is reciprocally movable. In the illustrated embodiment, piston120includes a lip seal122and an annular seal such an O-ring124to form a sealing engagement between piston120and cylinder130. Use of such seals are known to those skilled in the art of pressurizing pistons. A pump volume, space or cavity140(below piston120in the illustrated embodiment) is maintained at a certain volume by the biasing force created by a biasing mechanism such as spring150when there is no pressure exerted upon piston120. In other words, piston120or other pressurizing mechanism hereof is biased in a first direction as illustrated inFIG. 3. Biasing mechanism other than springs (for example, elastomeric members, fluid or pneumatic systems etc.) may be used herein. In general, extensible or compressible biasing mechanisms which do not require power input (for example, electrical power, chemical power etc.) are used in a number of embodiments hereof.

Pumping device100further includes an inlet port160and an outlet port170in fluid connection with pump volume140. Each of inlet port160and outlet port170includes a one-way or check valve162and172, respectively. In the illustrated embodiment, each check valve162and172is a ball valve which includes a ball biased (for example, by a spring) to close inlet port160and outlet port170, respectively.

Piston120of pumping device100is in operative or fluid connection with pressurized system14via a fluid connector180. When a positive fluid pressure is exerted upon an upper surface of piston to overcome the rearward or upward biasing force exerted by spring150, piston120is forced forward or downward (in the illustrated orientation) toward a base section112of housing120. As, for example, illustrated inFIG. 4A, as piston120is moved forward toward base section112, the size (volume) of pump volume140is decreased, and pressure increases within pump volume140. The increase in pressure in pump volume140causes check valve172to open so that fluid from pump volume140is pumped through outlet port170. The pressure within pump volume140, however, maintains check valve162in a closed position. When fluid pressure exerted upon piston120by pressurized system14is decreased, biasing spring150forces piston120rearward or upward (away from base section112), increasing the size (volume) of pump volume140. The resultant decrease in pressure within pump volume140causes check valve162to open (as, for example, illustrated inFIG. 4B), and fluid is drawn into pump volume140via inlet port160. Check valve172remains closed during rearward or upward movement of piston120.

In a number of representative embodiments as described above, pressurized system14is a coolant system. Each time coolant system14is activated, an increase in pressure forces piston120downward, compressing spring150. For example, a liquid pressure resulting from activation of coolant system14may be 60 pounds per square inch (psi). As piston120is forced toward base section112, it creates a downward or forward pump stroke that forces liquid from pump volume140out through outlet port170to a system16(seeFIG. 1). When coolant system14is, for example, deactivated, the pressure on piston120is removed, and spring150forces piston120away from base section120in a rearward or upward stroke as described above. Liquid from pan12is thereby drawn into pump volume140via inlet port160. Each increase in pressure results in a forward or downward pump stroke that causes liquid to be forced out of pump device100via outlet port170, and each reduction in pressure causes a rearward or upward stroke (powered by spring150) wherein liquid is drawn into pump device100via inlet port160.

Pump device100may, for example, be used to remove drainage in the bottom of pan112, in system10. Such liquid (for example, a coolant or lubricant) may, for example, be recovered and pumped to a device or system such as system16for recycled use. In other embodiments, the liquid may be recovered and pumped to, for example, a waste container or reservoir. Pump device100may thereby assist in maintaining environmental control of any liquids that, in previously available systems, had run over onto the floor or had to be removed manually.

Pump device100may, for example, be powered by any fluid flow (which has at least one state wherein the flow is under suitable pressure to overcome the biasing force of spring150or other biasing mechanism) in the machine, device or system in connection with which pump device100is used. No fluids need be exchanged between the powering fluid flow and the fluid pumped by pump device100. A closed loop can be used to power pumping device100.

Pump device100may be connected and operated almost anywhere along, for example, a flow or fluid line of other pressurized volume of a system. Hydraulically, the fluid will exerts essentially the same force anywhere along the flow line, minus, for example, frictional losses. Further, there is almost no frictional loss resulting in pump device100as a result of the small amount of flow required to power piston120. Therefore, the distance that the pressurizing/powering fluid is pumped or the distance from the pump supplying the pressurizing/powering fluid are not normally determining factors in the function of this device. Additionally, chemical interactions, electrical connections or other issues are typically not important in pumping device100. Seals such as seals122and124may, for example, be configured in many ways that are currently known in the pumping industry. The seal materials may be readily matched to the fluids that will be pumped. Seals that are chemically resistant (for example, oil resistant) are readily available.

Using well established engineering principles, pump device100may be tuned to a wide variety of input pressures from system14. Variables that may be readily determined include, but are not limited to, input pressure change, the biasing force of the biasing mechanism, system component dimensions and materials, and flow rates into and out of the pump device100. The volume of liquid pumped with each stroke of piston120can vary over a very broad range. For example, the liquid pumped with each piston stroke can vary between 1 and 1000 ml. In a number of embodiments, the liquid pumped with each piston stroke varied between approximately 10 and 30 ml.

The lengths of fluid connections such as hosing or tubing160a(in fluid connection with inlet port160and pan112), hosing or tubing170a(in fluid connection with outlet port170aand the destination reservoir for the liquid pumped from pan112) and hosing or tubing180a(in fluid connection with fluid connector180and with a fluid line of system14) as, for example, illustrated inFIG. 4B, may be varied independently over a wide range (for example, from millimeters to many meters). This variability in fluid connection provides substantial flexibility for the location of pump device100. Pump device100may, for example, be placed in venues that are very difficult to reach by or even hazardous to personnel.

Pump device100thus allows the use of power derived from a fluid that is already being pumped within a system with relatively small amounts of energy used to recover liquid that, for example, drips into a collection area or volume. As described above, in a number of embodiments, pump device100may deliver a relatively small amount of a lubricant to one or more systems upon the occurrence of a state change (for example, when a system is activated or turns on). Collected liquid may also be pumped by pump device100to a reservoir from which it may, for example, be recycled, further processed or discarded. Pump device100is inexpensive to manufacture and to operate, while providing significant reliability, durability and reduced labor costs.

FIGS. 5A and 5Billustrate another representative embodiment of a pumping device or system200hereof. Similar to pumping device100, pumping device200includes a pump housing210in which a movable pressurizing mechanism such as a piston220is movably positioned. In the illustrated embodiment, housing210is form in three sections210a,210band210cmay, for example, be formed from any suitable material (for example, polymeric materials, metallic materials etc.) and may, for example, be connected via cooperating threaded portions, adhesives etc. Piston220may, for example, include one or more seals224(for example, one or more O-rings) to form a sealing engagement with a cylinder230in which piston220is reciprocally movable. A pump volume240(below piston220in the orientation of the illustrated embodiment) is maintained at a certain volume by the biasing force created by a biasing mechanism such as spring250when there is no pressure exerted upon piston220.

Pumping device200further includes a flow path or system260, which is placed in fluid connection with volume240via a port214formed in housing210(in housing section210cin the illustrated embodiment). Flow system260may, for example, be connected to port210via cooperating threaded fittings, an adhesive, a snap fit etc. In the illustrated embodiments, flow path260includes an inlet conduit270in fluid connection with a check valve272, which includes an inlet port274. Flow path260further includes an outlet conduit in fluid connection with a check valve282including an outlet port284. an inlet port160and an outlet port170in fluid connection with pump volume140. In the illustrated embodiment, each one-way check valve272and282include a ball valve as described above (which includes a ball biased (for example, by a spring) to close inlet port274and outlet port284, respectively, as described above in connection with check valves162and172.

A number of currently available pump devices are powered by electric motors. In many cases, such pump devices can be non-water tight and/or non-oil tight. In general, such devices are significantly less reliable than pump device100and other pump devices hereof. Moreover, unlike the pump devices hereof, pump devices including electrical motor and associated check valves can lose their prime. Pump device100and other pump devices hereof will not lose prime. Pump devices hereof (which may, for example, sit at the bottom of a tank or a drip pan) can function against spring150or other biasing mechanism if there is only air/gas present in pump volume140, if there is combination of air and liquid present in pump volume140or if only liquid is present in pump volume140. Pump devices hereof are self-priming and do not require electrical switches, liquid level sensors, or motors, resulting in increased mechanically reliable as compared to other pump devices.

The foregoing description and accompanying drawings set forth the preferred embodiments of the invention at the present time. Various modifications, additions and alternative designs will, of course, become apparent to those skilled in the art in light of the foregoing teachings without departing from the scope of the invention. The scope of the invention is indicated by the following claims rather than by the foregoing description. All changes and variations that fall within the meaning and range of equivalency of the claims are to be embraced within their scope.