Fluidic delivery systems are employed for processing and/or delivering many different types of fluids for a wide range of applications. Such delivery systems can be tailored to the fluid(s) with which they are used, and can include metering (measuring or dosing) devices/apparatus. Often times such fluid delivery systems utilize an active pump of some kind such as a piston, turbine, or diaphragm.
Fluids including solid aggregates or large particles have proven to be problematic for fluid delivery devices and systems of the prior art often resulted in malfunctioning of valves and/or damaging the aggregates contained in the fluid
Thus, there exists a need for techniques that provide improved performance characteristics useful for metering and pumping fluids that include solid aggregates.
Embodiments of the present disclosure can provide techniques, e.g., apparatus and methods, useful for metering fluids with solid aggregates, e.g., such as concrete and various food products like creams with chocolate chips, and the like.
The present disclosure presents several exemplary embodiments for metering devices, some of which also have pumping capability. An advantage afforded by such embodiments is that they employ a minimal number of moving parts and do not explicitly use one way valves that are common in other metering devices and pumps. These features make the devices especially suitable for fluids with solid aggregates (e.g., such as concrete and various food products like creams with chocolate chips), which in the prior art have proven troublesome.
In certain exemplary embodiments, devices use passive pistons that, in conjunction with pressurized fluid supplied as input, perform only metering (or dosing) functions. In certain other exemplary embodiments, devices can utilize active pistons that can create pressure as well as suction, and therefore also act as pumps in addition to metering devices.
Various techniques useful in conjunction with the subject matter of the present application are described in: U.S. patent application Ser. No. 10/760,963, entitled “Multi-Nozzle Assembly for Extrusion of Wall,” Attorney Docket No. 28080-115, filed Jan. 20, 2004, which claims priority to and incorporates by reference U.S. Provisional Application Ser. No. 60/441,572, entitled “Automated Construction,” Attorney Docket No. 28080-097, filed Jan. 21, 2003; U.S. patent application Ser. No. 11/040,401, entitled “Robotic Systems for Automated Construction,” Attorney Docket No. 28080-149, filed Jan. 21, 2005; the entire contents of all of which applications are incorporated herein by reference.
Additional useful techniques are described in U.S. patent application Ser. No. 11/040,602, entitled “Automated Plumbing, Wiring, and Reinforcement,” Attorney Docket No. 28080-154, filed Jan. 21, 2005, and U.S. patent application Ser. No. 11/040,518, entitled “Mixer-Extruder Assembly,” filed Jan. 21, 2005, Attorney Docket No. 28080-155, all three of which claim priority to U.S. Provisional Application Ser. No. 60/537,756, entitled “Automated Construction Using Extrusion,” Attorney Docket No. 28080-124, filed Jan. 20, 2004; U.S. Provisional Applications: Ser. No. 60/730,560, entitled “Contour Crafting Nozzle and Features for Fabrication of Hollow Structures,” Attorney Docket No. 28080-190, filed Oct. 26, 2005; Ser. No. 60/730,418, entitled “Deployable Contour Crafting Machine,” Attorney Docket No. 28080-191, filed Oct. 26, 2006; Ser. No. 60/744,483, entitled “Compliant, Low Profile, Non-Protruding and Genderless Docking System for Robotic Modules,” Attorney Docket No. 28080-202, filed Apr. 7, 2006; the entire contents of all of which applications are incorporated herein by reference.
Additional useful techniques are described in U.S. Patent Application Ser. No. 60/807,867, entitled “Lifting and Emptying System for Bagged Materials,” Attorney Docket No. 28080-212, filed Jul. 20, 2006; U.S. patent application Ser. No. 11/552,741, entitled “Deployable Contour Crafting,” Attorney Docket No. 28080-227, filed Oct. 25, 2006, and U.S. patent application Ser. No. 11/552,885, entitled “Extruded Wall with Rib-Like Interior,” Attorney Docket No. 28080-229, filed Oct. 25, 2006; U.S. Provisional Patent Application Ser. No. 60/733,451, entitled “Material Delivery Approaches for Contour Crafting,” filed Nov. 4, 2005, attorney docket no. 28080-193; and U.S. Provisional Patent Application Ser. No. 60/820,046, entitled “Accumulator Design for Cementitious Material Delivery,” filed Jul. 21, 2006, attorney docket no. 28080-216; U.S. patent application Ser. No. 11/566,027, entitled “Material Delivery System Using Decoupling Accumulator,” Behrokh Khoshnevis, Inventor; Attorney Docket No. 28080-231, filed Nov. 2, 2006; and U.S. patent application Ser. No. 11/556,048, entitled “Dry Material Transport and Extrusion,” Attorney Docket No. 28080-246, filed Nov. 2, 2006; the entire content of all of which applications is incorporated herein by reference.
Other features and advantages of the present disclosure will be understood upon reading and understanding the detailed description of exemplary embodiments, described herein, in conjunction with reference to the drawings.
Aspects of the disclosure may be more fully understood from the following description when read together with the accompanying drawings, which are to be regarded as illustrative in nature, and not as limiting. The drawings are not necessarily to scale, emphasis instead placed on the principles of the disclosure. In the drawings:
While certain embodiments depicted in the drawings, one skilled in the art will appreciate that the embodiments depicted are illustrative and that variations of those shown, as well as other embodiments described herein, may be envisioned and practiced within the scope of the present disclosure.
The present disclosure presents several embodiments for metering devices some of which also have pumping capability. The devices utilize one or more pistons located within a cylindrical rotor. It should be noted that as the term is used herein, “piston” includes reference to a device element of a desired shape (not necessarily cylindrical) that is used as a reciprocating element within a cylindrical rotor.
As the cylindrical rotor is turned by suitable torque/power source, a first face of each piston is exposed to an inlet supplying a pressurized fluid to be metered, e.g., a cementitious mix with aggregates. The piston then moves—either through applied power or by the force of the fluid within the associated channel or bore within the rotor, allowing the volume of the channel to be filled with fluid. The continuing rotational motion of the rotor then removes the piston from the fluid supply and moves the channel through an angular displacement (e.g., 180 degrees), where the piston is then moved—either through applied power for active piston embodiments or the force of the fluid supply in passive piston embodiments—in the opposite direction, forcing the fluid out of the channel. In this way, a precise amount of fluid (e.g., volumetric flow rate) can be metered from each channel, taking into consideration the speed of rotation of the rotor and the pressure of the fluid supply or power applied to the pistons.
An advantage of such embodiments is that they employ a minimal number of moving parts and do not explicitly use one way valves that are common in most other metering devices and pumps. These features make the devices especially suitable for fluids with solid aggregates (e.g., such as concrete and various food products like creams with chocolate chips), which in the prior art have often resulted in malfunctioning of valves and or damaging the aggregates included in the fluid.
As noted previously, certain exemplary embodiments are directed to metering devices that use passive pistons that, in conjunction with pressurized fluid supplied as input, perform only metering (or dosing) functions. In certain other exemplary embodiments, metering devices of the present disclosure can utilize active pistons that can create pressure as well as suction, and therefore can also act as pumps in addition to as metering devices.
The rotor 102 can be turned by an energized source such as an electric motor or the like and, to facilitate such, can include an extension 105. The rotor 102 is configured to spin inside a chamber of a chamber housing 106 that has openings 107(1)-107(2) for incoming and outgoing fluid volumes. In exemplary embodiments, the chamber housing 106 may be made of a suitable elastomeric material such as rubber, though other materials may be used. The chamber housing 106 itself can be located within a receiving aperture 109 of outer housing portion 108, which may be connected to fluid ports 111(1)-111(2) acting as inlet and outlet to the device 100. To facilitate the rotation of the rotor 102, one or more bearings, e.g., 112, may be positioned within outer housing portions 108 and 110.
With particular reference to the exploded view depicted in
As the piston 104 moves away, incoming material (fluid) occupies the space in the channel 101 that the piston leaves behind (e.g., that is swept by the piston 104). As the rotor 102 continues to spin it locates the filled section of the channel 101 in front of the outlet, e.g., opening 107(1), while at the same time the opposite piston face, due to the rotation of the rotor 102, is positioned again in front of the opening (e.g., 107(2) corresponding to the inlet 111(2).
In the passive piston embodiment of
In this configuration the dosing (or metering) resolution of the device 100 is equivalent to the volume of the channel 101 minus the volume of the piston 104 itself, i.e., one channel capacity. The smaller the channel 101, the finer the dosing resolution of the device 100 becomes. For smaller channels 101, a faster rotor spin could result in comparable overall flow rate of a similar device that has a larger channel capacity but rotates at a slower speed. Thus, one skilled in the art can appreciate that the channel capacity may be designed by a combination of the piston size and rotor diameter (i.e., channel depth).
With particular reference to
With reference to
The metering device 300 of
In the embodiment of
In operation of device 300, pressurized fluid is supplied from inlets 314(1)-314(2) to the inlet chambers 315(1)-315(2) within housing members 310(1)-310(2). the pressurized incoming fluid push the pistons 304(1)-304(2) located in the corresponding channels 301(1)-301(4) (chambers) away from the fluid inlet chambers, e.g., chambers 315(1)-315(2). This action fills the volume of the respective channels on the incoming fluid side with fluid, while at the same time pushing the material (fluid) on the opposite side of the pistons 304(1)-304(2) to the corresponding outgoing chambers 316(1)-316(2) on the opposite side (relative to the rotor axial direction) of the previously described incoming fluid chambers 315(1)-315(2). A similar process takes place in the adjacent chambers but in reverse flow directions. The metered fluid then leaves outlet chambers 316(1)-316(2), leaving the device 300 through outlets 312(1)-312(2) connected to the housing members 310(1)-310(2).
It should be noted that device 300 can have two fluid inlets and two outlets, as shown. In exemplary embodiments, however, the two inlets and/or the outlets can be connected together to create a single inlet and a single outlet. The dosing (metering) resolution of this device 300 can be equivalent to the volume of each channel. Using a desired number of pistons, device 300 can be designed to deliver higher flow rates at slower rotational speeds.
In exemplary embodiment, device 300, when its two inlets 314(1)-314(2) and outlets 312(1)-312(2) are not connected together, can concurrently dose two separate fluids without mixing them. Besides the obvious advantage of the ability to dose double fluids at the same rate (such as dispensing equal amounts of vanilla and chocolate ice cream), the device can work as a pressure amplifier and thus active pump for one of the fluids. For example, high pressure water may be used as one incoming fluid and low pressure concrete as the second incoming fluid. In this case when the rotor is turned the concrete will be pushed out of the system at the high water pressure. The normal water line pressure or a powerful water pump may be used in this case. In case a pump is used the water may be recycled through a closed loop back to the pump. The pump in this case supplies pressure at its outlet and suction on its inlet. The suction action would pull the pistons positioned in the device 300 chamber which is connected to the water pump inlet and thus make it possible to suck in the second fluid material. Therefore, an unpressurized (i.e., at atmospheric pressure) material such as concrete at atmospheric pressure could be pumped by this arrangement. Note that the circulating fluid in this case may be a special oil (instead of water) which is commonly used in hydraulic actuators. In summary, in this closed loop case the high pressure water (or oil) circuit uses the inlet and outlet chambers on one side of device 300 and plays the role of a novel hydraulic pumping system to pump the material that enters and leaves respectively the inlet and outlet chambers on the opposite side of the device. Of course material flow takes place at the desired rate when the rotor in device 300 is turned by its own external torque source.
Like the previously described embodiments, device 400 includes a cylindrical rotor 402 that is turned by a torque applied to an extension (or axle) 405. Unlike previously described embodiment, however, device 400 uses active pistons 404(1)-404(5) that are actuated by means of their rods attached to bearings 408(1)-408(5) that move inside a tilted stationary groove 407 that is configured in an arched member 406 and that is tilted at oblique angle with respect to the axis of rotation of the rotor 402. The groove 407 is configured to retain the bearings 408(1)-408(5) in sliding manner such that the bearings 408(1)-408(5) are slidingly retained within the groove 407 as the rotor turns. The arched member 406 can receive axle 405 and be connected to housing member 410 that includes inlet chamber 412 and outlet chamber 414 connected to inlet 411 and outlet 413 respectively. Sealing gasket 415 may also be present.
In operation, as the rotor 402 is turned by an external torque source, the rotation of the rotor 402 forces each piston rod against the bearings which in turn causes their movement inside the grove 407. This arrangement results in the sequential rising and lowering of pistons 404(1)-404(5) in their respective channels 401(1)-401(5), thereby providing a pumping action for each. The rising action takes place above the incoming fluid chamber, e.g., chamber 412, and the lowing action happens above the outgoing fluid chamber, e.g., chamber 414. The dosing resolution in of the device 400 can thus be designed to be very fine, while allowing the flow through the device 400 to be continuous.
As can be seen in the exploded view of
As can be seen in
With continued reference to
In certain embodiments, device 500 may be used in a passive mode with pressurized incoming fluid, in which case the dosing resolution will be equivalent to the channel containing the piston 504.
Due to its advantage of making the piston pivoting shaft ends 503(1)-503(2) available to outside the housing that contains the rotor, device 500 can be utilized as an active pump (or a continuous dosing device), as can be seen in
In such active embodiments, the rotor end spins with respect to the body of the housing 508. It is therefore possible to convert the rotary motion of the rotor 502 to reciprocating pivoting motion of the piston shaft by means of several possible rotary-to-reciprocating motion conversion mechanisms.
One possible mechanism is shown in (
While certain embodiments have been described herein, it will be understood by one skilled in the art that the methods, systems, and apparatus of the present disclosure may be embodied in other specific forms without departing from the spirit thereof. For example, in all of the above designs, a diaphragm or other alternatives to pistons may be used.
Accordingly, the embodiments described herein, and as claimed in the attached claims, are to be considered in all respects as illustrative of the present disclosure and not restrictive.
This application claims the benefit of U.S. Provisional Application Ser. No. 60/864,060, entitled “Metering and Pumping Devices,” Attorney Docket No. 28080-251, filed Nov. 2, 2006 and U.S. Provisional Application Ser. No. 60/864,291, entitled “Metering and Pumping Devices,” Attorney Docket No. 28080-252, filed Nov. 3, 2006; the entire contents of both of which applications are incorporated herein by reference.
This invention was made with government support under Office of Naval Research Grant No. N000140510850 awarded by the United States Government. The government has certain rights in the invention.
Number | Date | Country | |
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60864060 | Nov 2006 | US | |
60864291 | Nov 2006 | US |