Patent Application
20250196169
The present disclosure relates generally to fluid dispensing systems and in particular to portable airless paint sprayers.
Portable airless paint sprayers are an ideal tool for hobbyists or do-it-yourselfers to paint surfaces, such as furniture, cabinets, trim, or other architectural structures. Unlike expensive and cumbersome pneumatic paint sprayers, requiring an air compressor and hosing, airless paint sprayers are able to finely atomize fluid paint in a compact, easy to maneuver packaging, providing professional high quality paint finishes.
Typical airless paint sprayers function by pressurizing fluid (e.g., paint, lacquers, stains, or varnishes) up to and exceeding 3000 psi and discharge the pressurized fluid through one or more small, shaped orifices. Such airless paint sprayers pressurize the fluid paint using an electric motor, a gasoline motor, or an air compressor. In larger scale applications, the power unit is connected to a stationary paint source, such as a 5-gallon bucket, and pressurize paint is supplied to a spray gun with a hose. For smaller scale applications, it may be desirable to create a compact paint sprayer, which includes an electrical motor to pressure the paint and an integrated fluid container for holding fluid paint. Such smaller compact airless paint sprayers may be powered for example by a rechargeable 20V battery or alternatively include a power cord to connect to traditional power outlet.
Traditional compact airless paint sprayers, including for example, buzz guns or cup guns, suffer from lack of performance resulting in less-than professional finishes due to, at least in part, the low pressures generated by the smaller electric motors and inferior spray nozzles that are used to accommodate these lower pressures. Thus, it may be desirable to provide a compact handheld airless paint sprayer capable of producing professional grade paint finishes, which uses a smaller electric motor and powered by a rechargeable battery or common electrical outlet.
A portable airless paint sprayer is disclosed, substantially as illustrated by and described in connection with at least one of the figures, as set forth more completely in the claims.
Specifically, disclosed is an embodiment of a stem-less valve for a fluid spraying apparatus. The stem-less valve comprises a cylindrical valve body, including a sealed end and an open end; a movable plug at least partially disposed within the cylindrical valve body proximate the open end; an air cavity disposed between the movable plug and the sealed end of the cylindrical valve body; at least one seal surrounding the movable plug, operable to seal air within the air cavity; a seat, shaped to conform to a shape of the movable plug; a spray orifice positioned downstream from the seat; a fluid conduit, the fluid conduit being operable to allow a flow of a fluid from a pump, at least partially through the cylindrical valve body, to a spray orifice positioned downstream from the seat; and a spring disposed within the air cavity. The spring is positioned between the sealed end of the cylindrical valve body and the movable plug. The spring biases the movable plug against the seat to prevent the fluid from flowing through the fluid conduit to the spray orifice when a fluid pressure is below a spray pressure threshold. The spring compresses when the fluid pressure reaches or exceeds the spray pressure threshold, at least partially retracting the movable plug away from the seat, and allowing the fluid to flow through the fluid conduit to the spray orifice.
In another embodiment, the spray pressure threshold is between 800 PSI and 2000 PSI. In a further embodiment, the movable plug comprises a cylindrical body and a head joined to the cylindrical body. In some embodiments, the head of the movable plug has a frustoconical shape. In such an embodiment, the cylindrical body of the movable plug includes at least one groove and the groove is operable to receive the at least one seal. In other embodiments, the spring comprises a compression spring. In another embodiment the air cavity when compressed by the movable plug is operable to function as a damper to the spring to reduce vibration of the spring resulting from an operation of the pump or a motor operably connected to the pump. In some embodiments, the spring is isolated from the fluid. In other embodiments the movable plug further comprises a stopper, operable to inhibit the movable plug from retracting away from the seat beyond a preferred distance. Finally, in one embodiment the sealed end comprises a threaded plug, threaded into the cylindrical valve body.
Also disclosed is another embodiment of a stem-less valve for a fluid spraying apparatus. The stem-less valve comprises: a cylindrical valve body, including an upstream end and a downstream end; a fluid conduit, operable to allow a fluid to flow from a pump, through the cylindrical valve body, to a spray orifice positioned downstream from the cylindrical valve body; a movable plug disposed within the cylindrical valve body; a seat, shaped to conform to a shape of the movable plug, the seat being disposed within the cylindrical valve body adjacent the upstream end; and a spring disposed within the cylindrical valve body. The spring biases the movable plug against the seat to prevent the fluid from flowing through the fluid conduit to the spray orifice when a fluid pressure is below a spray pressure threshold. The spring compresses when the fluid pressure reaches or exceeds the spray pressure threshold, at least partially retracting the movable plug away from the seat, and allowing the fluid to flow through the fluid conduit to the spray orifice.
In another embodiment, the cylindrical valve body further comprises: a downstream portion, including a threaded bore; and a removable upstream portion, including threads disposed around the removable upstream portion, wherein: the threads of the removable upstream portion are operable to engage with the threaded bore of the downstream portion to fasten the removable upstream portion to the downstream portion to retain the spring and movable plug within the cylindrical valve body. In some embodiments, the spray pressure threshold is between 800 PSI and 2000 PSI. In other embodiments, spring comprises a compression spring.
Also disclosed is an embodiment of a handheld fluid dispensing apparatus. The handheld fluid dispensing apparatus comprising: a housing, the housing including a handle; an electric motor positioned within the housing, the electrical motor operable to output a rotational motion; a drive, positioned within the housing, operably coupled to the electric motor, the drive operable to convert the rotational motion to a reciprocating linear motion; an actuator disposed on the housing adjacent the handle, the actuator operable to actuate the electric motor; a fluid container mounted to the housing, the fluid container operable to receive and retain a fluid; and a pump, positioned within the housing, operably coupled to drive, the pump operable draw the fluid from the fluid container, pressurize the fluid, and drive the fluid through a stem-less valve to a spray orifice, positioned downstream from the stem-less valve. The stem-less valve comprises: a valve body, the valve body being generally cylindrical; a fluid conduit, operable to allow a flow of the fluid from the pump, at least partially through the valve body, to the spray orifice; a movable plug disposed at least partially within the valve body; a seat, shaped to conform to a shape of the movable plug; a spring disposed within the valve body. The spring biases the movable plug against the seat to prevent the fluid from flowing through the fluid conduit to the spray orifice when a fluid pressure is below a spray pressure threshold. The spring compresses when the fluid pressure reaches or exceeds the spray pressure threshold, at least partially retracting the movable plug away from the seat, and allowing the fluid to flow through the fluid conduit to the spray orifice.
In another embodiment, a tip guard mounted to the housing; the tip guard including a bore; and a reversible spray tip, including a barrel. The barrel is insertable into the bore of the tip guard and rotatable within the bore; and the spray orifice is disposed within the barrel. In some embodiments, the spray pressure threshold is between 800 PSI and 2000 PSI. In other embodiments, the spring comprises a compression spring. In another embodiment, the valve body further comprises an open end and a sealed end; and the movable plug further comprises a cylindrical body, a head, and at least one seal surrounding the cylindrical body; wherein: the cylindrical body of movable plug encloses an air cavity between the movable plug and the sealed end of the cylindrical valve body; and the at least one seal is operable to seal air within the air cavity. In a further embodiment, the head of the movable plug has a frustoconical shape.
Also disclosed is another embodiment of a handheld fluid dispensing apparatus. The handheld fluid dispensing apparatus comprises: a housing, the housing including a handle; an electric motor positioned within the housing, the electrical motor operable to output a rotational motion; a drive, positioned within the housing, operably coupled to the electric motor, the drive operable to convert the rotational motion to a reciprocating linear motion; an actuator disposed on the housing adjacent the handle, the actuator operable to actuate the electric motor; a fluid container mounted to the housing, the fluid container operable to receive and retain a fluid; a pump, positioned within the housing, operably coupled to drive, the pump operable draw the fluid from the fluid container, pressurize the fluid, and drive the fluid downstream of the pump atomize the fluid; a relief valve connected to and positioned downstream of the pump, the relief valve operable to prime the pump and redirect the fluid back into the fluid container when a fluid pressure output by the pump exceeds a relief pressure threshold; a spray valve, connected to and positioned downstream of the relief valve; and a spray tip assembly, connected to and positioned downstream of the spray valve, the spray tip assembly included a spray orifice operable to atomize the fluid.
In such an embodiment, the spray valve comprises: a valve body, the valve body being generally cylindrical; a fluid conduit, operable to allow a flow of the fluid from the relief valve, at least partially through the valve body, to the spray orifice of the spray tip assembly; a frustoconical plug disposed at an end of a stem, wherein the frustoconical plug and the stem are positioned entirely within the valve body; a seat, shaped to conform to a shape of the frustoconical plug; a spring disposed around the stem and positioned within the valve body. The spring biases the frustoconial plug against the seat to prevent the fluid from flowing through the fluid conduit to the spray orifice when a fluid pressure is below a spray pressure threshold. The spring compresses when the fluid pressure reaches or exceeds the spray pressure threshold, at least partially retracting the frustoconical plug and stem away from the seat, and allowing the fluid to flow through the fluid conduit to the spray orifice.
The following is a brief description of the drawings pertaining to the present disclosure, which will be discussed in more detail in the detailed description section below:
The foregoing summary, as well as the following detailed description of certain features of the present application, are better understood when read in conjunction with the appended drawings. For the purposes of illustration, certain features are shown in the drawings. It should be understood, however, that the claims are not limited to the arrangements shown in the attached drawings. Although specific features of various embodiments may be shown in some drawings and not in others, this is for convenience only. Any feature of any drawing may be referenced and/or claimed in combination with any feature of any other drawing.
Unless otherwise indicated, the drawings provided herein are meant to illustrate features of embodiments of the disclosure. These features are believed to be applicable in a wide variety of applications comprising one or more embodiments of the disclosure. As such, the drawings are not meant to include all conventional features known by those of ordinary skill in the art to be required for the practice of the embodiments disclosed herein.
The spray valve 100, relief valve 200, pumping mechanism 30, and motor 40 are each at least partially contained in, and packaged within, the housing 10. The spray tip assembly 20 is removably connected to the spray valve 100, for ease of maintenance and cleaning. Likewise, the fluid container 50 is removably connected to the housing 10, such that it can be easily removed to fill with paint or other fluid to be dispensed by the apparatus 1. As shown in
Regardless of which configuration is being utilized, the portable airless fluid dispensing apparatus 1 generally functions as follows. Fluid contained within the fluid container 50 is drawn into the pumping mechanism 30 and pressurized within the pumping mechanism 30 utilizing power from the motor 40. The pressurized fluid then flows through the relief valve 200 to the spray valve 100. Once a sufficient spray pressure threshold has been reached, the spray valve 100 opens and permits the pressurized fluid to pass to the spray tip assembly 20 and specifically the spray orifice (not shown), which atomizes the fluid upon existing the spray tip assembly 20. An example spray orifice ideally has area between 0.001 to 0.05 square inches and is operable to atomize fluid (e.g., paint, lacquers, stains, or varnishes) to approximately 150 microns or smaller. In operation for example, the pumping mechanism 30 being driven by the motor 40, may generate a spray pressure threshold, of approximately 800-1500 psi. It is however understood that depending on the power of the motor 40, lower or higher spray pressure thresholds may be achieved. For example, in larger form factor examples, a spray pressure threshold of approximately 1000 to 3000 PSI may be desirable. When fluid pressure exceeds the spray pressure threshold, the relief valve 200 is operable to release some of the pressurized fluid back into the fluid container 50 if the fluid pressure has reached a relief pressure threshold. A typical relief pressure threshold is 2500-3000 PSI, but may be higher depending on the size and spray pressure threshold of the apparatus 1. Likewise, the relief valve 200 is operable to expose the pump 30 to atmospheric pressure to prime the pump 30.
The fluid container 50 contains any fluid (e.g., paint, lacquer, stain, varnish, etc.), which is suitable for being atomized and sprayed by the apparatus 1. The fluid container 50 is operably coupled to the remainder of the apparatus 1, and specifically to the pumping mechanism 30 and spray tip assembly 20. In one example, the trigger 11 is operationally connected to the power source 13 and motor 40, such that when the trigger 11 is actuated, power from the power source 13 activates the motor 40. The motor 40 in turn provides power input into the pumping mechanism 30, which draws fluid from the fluid container 50 via a suction tube 51. Specifically, the motor 40 is operably coupled to the pumping mechanism 30 by a connecting assembly 41 and gearing assembly 42. The pumping mechanism 30 pressurizes the fluid and forces the pressurized fluid through the spray tip assembly 20.
As shown in
The apparatus 1 may further include a circuit board (not shown), operable to control the motor 40. For example, the circuit board may be programmed to alter the current and/or voltage supplied to drive motor 40 to alter the flow from the pumping mechanism 30. Likewise, the circuit board may be programmed to use pulse width modulation (PWM) to slow output of the motor 40 when high current is being drawn from the power source. Additionally, the circuit board may include a temperature sensor 16, operable to monitor temperatures of the motor 40 and/or power source.
The apparatus 1 depicted in
Each of the spray valves 100 shown
The spring 140 biases the movable plug 120 towards the seat 130. The movable plug 120 and seat 130 are positioned in-line with the fluid conduit 101, such that when the movable plug 120 is seated on the seat 130, the fluid conduit 101 is blocked and fluid cannot pass beyond the movable plug 120. Thus, when the apparatus 1 is turned off or if the fluid pressure of the fluid is below the spray pressure threshold, the movable plug 120 is seated on the seat 130 in closed position, and fluid is not capable of passing through the fluid conduit 101. When the apparatus 1 is activated by actuating trigger 11 (as described above), the pumping mechanism 30 draws fluid from the fluid container 50 and begins to pressurize the fluid. When the fluid pressure, of the fluid within the fluid conduit 101 reaches the spray pressure threshold, which correlates to the force required to compress or deform spring 140, the movable plug 120 retracts and/or is separated from the seat 130 in an open position. At this point, fluid can pass through the fluid conduit 101 to the spray trip 24 (and spray orifice 26). It is understood that the spray pressure threshold can by increased or decreased by adjusting the spring rate of the spring 140. For example replacing the spring 140 with a different spring having a lower or greater spring rate (i.e., the force a spring exerts as calculated by Hooke's law) may cause the spray pressure threshold to change.
As illustrated in
The spray valve 100 may also include an anchor portion 105 positioned generally upstream from the valve body 110. The anchor portion 105 may be integral with the outer wall 102 (i.e., machined from a single piece of material) or fastened within the outer wall 102. The anchor portion 105 is operable to provide a fixed anchor location for one or more spring(s) 140 or 240. The valve body 110 and outer wall 102 of the spray valve 100 may be machined metal (e.g., aluminum or stainless steel) or any other suitable material capable or withstanding the fluid pressure.
As illustrated in
To assemble the spray valve 100 of
As illustrated in
Each of the relief valves 200 shown
The spring 240 biases the movable plug 220 towards the seat 230. The movable plug 220 and seat 230 are positioned in-line with the relief conduit 201, such that when the movable plug 220 is seated on the seat 230, the relief conduit 201 is blocked and fluid (or air) cannot pass beyond the plug 220. As discussed above, relief valve 200 can be opened in one of two ways. Manually compressing the spring 240 via the priming switch can be compressed manually using the priming switch 17, or by fluid pressure if the fluid pressure has reached the relief pressure threshold. Specifically, the pressurized fluid pushes against a head 222, which compresses the spring 240 and retracts the movable plug 220 from the seat 230. The relief pressure threshold correlates to the force required to compress or deform the spring 240. It is understood that the relief pressure threshold can by increased or decreased by adjusting the spring rate of the spring 240. For example replacing the spring 240 with a different spring having a lower or greater spring rate (i.e., the force a spring exerts as calculated by Hooke's law).
The present described disclosure is described in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains to practice the same. It is to be understood that the foregoing described preferred aspects of the disclosure and that modifications may be made therein without departing from the spirit of scope of the disclosure as set forth in the appended claims. The scope of the following claims is to be accorded the broadest interpretation to encompass all such modifications and equivalent structures and functions. Therefore, it is intended that the application not be limited to the particular aspects disclosed, but that the application will include all aspects falling within the scope of the appended claims.
