Patent Application
20080213089
The present application relates to inflation devices, and, in particular, to inflation devices utilizing a cooling fan as a blower.
Inflation devices, or inflators, are used to inflate items such as vehicle and bicycle tires, air mattresses, and swimming flotation devices. In general, tires are compressed with air having a “high pressure, low volume,” while larger volume items, such as air mattresses and rafts, are inflated with air having a “low pressure, high volume.”
Existing inflators often have a “compressor-type” structure. The inflator will include a motor assembly that has, at one end, a reciprocating piston and pump. The motor will drive the piston so that the piston will compress the air that enters the pump. The resulting air will be highly pressurized and suitable for the inflation of tires. The motor and reciprocating action of the piston, however, generally produce a great-deal of heat. One solution to prevent the inflator from overheating is to extend the motor's shaft at the end of the motor opposite the end that includes the piston and pump and attach a radial fan. U.S. Pat. No. 5,252,033 to Lin demonstrates such a configuration. In such compressor-type structures, the fan will “blow” air across the components in order to cool them. The air is then exhausted out of the inflator
However, with such a configuration, some of the cooling air may disperse within the inflator and fail to be exhausted out of the inflator. The temperature of this air often will increase, thus resulting in an inefficient cooling system. In addition, the running fan itself may produce heat that fails to be exhausted, again resulting in inefficient cooling. Moreover, inefficient cooling may cause the inflator to increase in temperature to the point that it is “hot to the touch” and uncomfortable for a user.
Furthermore, such compressor type-structures produce “compressed air” that is high pressure, low volume. As described above, while compressed air is suitable for inflating tires, it is generally unsuitable for inflating larger-volume items because of the large amount of time required for inflation. U.S. Pat. No. 4,829,625 to Wang discloses a vacuum/air compressor that provides both high volume, low pressure air compression and low volume, high pressure air compression. The high volume, low pressure compression is suitable for inflating larger-volume items while the low volume, high-pressure air compression is suitable for inflating high tires. The Wang patent, however, fails to provide a solution regarding any potential overheating of the vacuum/air compressor.
An inflator is disclosed having a housing and a motor assembly within the housing. A first output line is in fluid communication with a first end of the motor assembly to provide a cooling path of air and a high-volume flow of air. The first output line provides a guiding path for the egress of the high-volume flow of air from the housing. A second output line is in fluid communication with a second end of the motor assembly and to provide a high-pressure flow of air.
The present disclosure also describes a dual-pressure inflator that also includes a housing and a motor assembly within the housing. A centrifugal fan is attached to a first end of the motor assembly and creates an axial path of cooling air. A blower housing is attached to the housing, surrounds the centrifugal fan, and provides a guided path for a high-volume flow of air. A crankshaft, piston and cylinder are attached to a second end of the motor assembly and provide a high-pressure flow of air opposite the high volume flow of air. A detachable high pressure hose is attached to the cylinder and provides an egress for the high-pressure flow of air from the housing.
The present disclosure also includes a process for operating an inflating mechanism. The process includes introducing the source of air into a housing. Additionally, the following are simultaneously created: a path of cooling air is created with a volute blowing mechanism; a high volume flow of air also is created with the volute blowing mechanism; and a high pressure path of air is created with a crankshaft, piston and pump cylinder.
Before describing the novel inflator, a brief explanation of prior art compressor structures will be helpful. Referring to
During the operation of the inflator, the motor 102 and reciprocating piston 106 generate heat that may become excessive. To solve this problem, the motor's shaft may be extended from a rear 114 of the motor (i.e., an end opposite the piston and cylinder), and a radial fan 116 may be attached. The fan 116 generates air to cool the components. However, the operation of the fan 116 may generate heat, which can remain inside the inflator and cause the inflator to become hot to the touch and make a user operating the inflator uncomfortable. Moreover, the inflator may end up overheating.
Turning now to
The inflator 2 also includes a removable battery housing 8 that houses a battery 10 in order to power the inflator. While
An air intake 9 is included that allows ambient air to enter into the housing that provides both high pressure and low pressure air as well as cooling air for components located within the inflator housing 4. While, in a preferred embodiment, the air intake 9 is located in a side wall 11 of the handle 6, the air intake 9 can be located elsewhere depending on the configuration of the inflator housing 4 and associated components (described further below).
The handle 6 is conventional and includes a trigger 13 that actuates a motor assembly 12 located within the inflator housing 4. Preferably, the handle 6 includes a lock-on member 18 that engages the trigger 12 so that the trigger 13 remains in an actuated position without requiring the user to “hold” the trigger 13.
The motor assembly 12 includes a motor 14 and a gear case 16 attached to a first end 14A of the motor 14. The gear case 16 reduces the amount of speed generated by the motor 14. Depending on the amount of reduction desired, the gear case 16 can include a variety of configurations. However, in a preferred embodiment the gear case 16 includes a pinion 20 and gear 22.
A crankshaft 24, piston 26 and pump cylinder 28 are attached to the first end 14A of the motor assembly 14. The gear case 16 reduces and transfers torque generated by the motor 14 to the crankshaft 24, which, in turn, drives the piston 26. The piston 26 compresses air within a cavity 30 of the pump cylinder 28. The air, which enters the inflator housing 4 via the air intake 9, enters the cavity 30 of the pump cylinder 28 through an inlet 32. Once the air within the cavity 30 is compressed, an outlet valve 34 associated with the pump cylinder 28 will open to allow the compressed air to exit the cavity 30. Once compressed, the air has a “high pressure flow.”
A detachable high-pressure hose 36, inserted through an opening 37 in the inflator housing, is attached to the outlet valve 34. For convenience, a cavity 40 in the inflator housing 4 is provided to store the high-pressure hose 36 when it is not in use. The hose 36 has a diameter such that the air that exits the pump cylinder 28 maintains a high pressure flow. Optionally, a chuck or valve 38 is fluidly connected to the high-pressure hose at an end 42 opposite the outlet valve 34. The chuck 38 allows the high-pressure hose 36 to be attached a valve stem for the inflation of items requiring high pressure flow, such as vehicle or bicycle tires.
A fan 44 is attached to a second end 46 of the motor assembly 12 and is driven by the motor 14. As explained further below, the fan provides both a high volume/low pressure flow of air (“high flow air”) and cooling air. In one preferred embodiment, the fan will have an outer diameter of 73 millimeters, a capacity of nine cubic feet per minute, and will be made of a glass-filled nylon material. In other embodiments, fans having a different size and capacity, as well as being made of a different material, may be used. Examples of other suitable materials include aluminum and poly carbonate. Moreover, although a preferred embodiment contemplates one fan, depending on the volume/pressure requirements for the air flow, more than one fan may be used in axial alignment at the second end 46 of the motor assembly 12.
The fan 44 is located within a blower housing 48 (
The blower housing 48 includes a guide 52 that provides a passage for, and prevents the dispersal of, high flow of air from the fan. Preferably, the high flow air will be projected in a direction tangential to the fan 44. Advantageously, the guide 52 also acts as a passage for the egress of heat generated by the pump cylinder 28 and the motor assembly 12, which exits with the high flow air generated by the fan 44.
Optionally, an end 58 of a detachable high-flow hose 60 may be attached to the guide 52. Generally, the high-flow hose 60 will have a diameter larger than the high-pressure hose and is suitable for inflating items that have larger volumes, such as air mattresses. An adapter 62 may be attached to the high-flow hose at an end 64 opposite the end 58 attached to the guide 52. The adapter 62 provides for the attachment of the high-flow hose to a valve (not shown) normally associated with an item for inflation. As with the high-pressure hose, the high-flow hose 60 may be stored in a second cavity 40 in the inflator housing.
The operation of the DC inflator will now be described: Upon actuation of the trigger 13, the motor assembly 14 is energized. The motor assembly 14, in turn, drives the fan 44 that is located within the blower housing 48. The fan 44 generates a centrifugal force. The centrifugal force draws air entering the air intake 9 across the pump cylinder 28, piston 26, crankshaft 24, and motor assembly 14. The air cools the afore-mentioned components. The circulation of the cooling air is shown in
At the same time it creates a source of cooling air, the fan 44 also creates high flow air for inflating larger-volume items. The fan 44 draws in the air entering through the opening 50 of the blower housing 48 and generates high flow air that passes into the guide 52. The high flow air and any heat generated by the fan then exit the inflator housing 4 through an exhaust opening 56 in the housing. Notably, the air exiting the exhaust opening may be used to “blow” accumulated debris. If the high-flow hose 60 is inserted through the exhaust opening 56 and attached to the guide 52, the hose 60 may be used to inflate high-volume items with the high flow air.
The high pressure flow is generated at the same time as the cooling air and high flow air. Upon its actuation, the motor assembly 14 also drives the crankshaft 24 and attached piston 26. As the piston moves downwardly, it creates a vacuum that draws air into the cavity 30 of the pump cylinder 28. As the piston 26 moves upwardly, it compresses the air, causing the air to become highly pressurized. The outlet valve 34 then opens to allow the high pressure air to exit the cavity 30 and pass into the high pressure hose 36. The diameter of the high pressure hose 36 maintains the pressure of the air high in order to inflate items requiring high pressure air.
Thus, a novel inflator has been described herein. The advantages associated with the inflator are numerous. First, only one motor is required to provide both high pressure flow and high flow air, thus reducing number of components associated with the inflator and, by extension, the size and weight of the inflator.
Second, the fan is advantageously utilized to simultaneously cool the inflator components and provide high flow air. As described above with respect to
It is therefore intended that the foregoing detailed description be regarded as illustrative rather than limiting. For example, although in a preferred embodiment the inflator 2 uses a battery power source, those skilled in the art will readily recognize that the inflator could utilize a cord that can be plugged into a car lighter or an AC outlet as possible power sources. Therefore, it is to be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention.
