AXIAL FAN BLOWER AND VACUUM

Abstract
The present invention is directed to an axial or in-line type blowervac that switches between a blowing operational mode and a vacuum operational mode by moving a baffle within its housing to cover an air inlet or air exhaust depending on the operational mode selected. In the blow mode, a fan assembly is driven in a first direction to blow air out of an airpipe attached to a front portion of the housing. In a vacuum mode, the fan assembly is driven in a reverse direction, and air and debris are pulled in through the airpipe.
Description
FIELD

The present disclosure relates to blowers and vacuums for outdoor use, specifically axial-fan or in-line type blowervac designs.


BACKGROUND

Axial-fan or in-line type blowers are known in the prior art, and typically include a fan whose axis is aligned with the air outlet so that the airflow is not forced to undergo any significant turn or bend, increasing airflow efficiencies. Examples of such designs are shown in U.S. Pub. No. 2012/0076672 and U.S. Pub. No. 2013/0239361.


Furthermore, devices that both blow and vacuum are known in the prior art. Typically, these devices include a main housing having the fan and at least two separate tubes, a first used when functioning as a blower, and a second tube used when functioning as a vacuum. Only one tube is attached to the housing at a time depending on whether the device is being used as a blower or vacuum, and the tubes must be swapped out when switching between the two. This process can be time consuming and difficult to carry out.


Accordingly, there remains a need in the art for an in-line blower that operates as both a blower and vacuum without having to swap out the air tubes.


BRIEF SUMMARY OF THE INVENTION

Therefore, the present invention discloses an axial or in-line type blowervac, that can be easily switched between its blowing operational mode and its vacuum operational mode. The blowervac includes a main housing with an airpipe connected to a front portion, and an air inlet and an air exhaust at a rear portion of the housing. A fan assembly, which is powered by a motor, is positioned within the housing so that its axis is aligned with the longitudinal axis of the airpipe.


A baffle is located within the housing and is moveable between a position where it covers the air inlet or the air exhaust. In this way, when the tool operates as a blower, the baffle covers the air exhaust, and air is pulled into the housing through the air inlet and exits the tool through the airpipe. When the tool operates as a vacuum, the baffle is moved to cover the air inlet, and the motor is reversed so that air is pulled into the tool through the airpipe and exits the tool through the air exhaust. A collection bag can be attached to the air exhaust to collect any debris vacuumed up by the tool. Importantly, the same airpipe is used is both modes and does not need to be swapped out when the operational mode is changed.


In an embodiment of the invention, the motor can be located outside the housing, for example beneath it, and connected to the fan assembly through a transmission. This allows the housing to be smaller and improves airflow efficiencies within the tool.


In another embodiment of the invention, an interlock mechanism is provided to prevent changing the operational mode between blowing and vacuuming while the tool is actuated.





BRIEF DESCRIPTION OF THE DRAWINGS

The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.



FIG. 1 is a perspective interior view of an exemplary tool constructed in accordance with the teachings of the present disclosure;



FIG. 2 is a perspective view of a fan assembly having a blender blade;



FIG. 3 is a front end view of the tool of FIG. 1;



FIG. 4 is a perspective view of the vane collar of the tool of FIG. 1;



FIGS. 5A and 5B are airflow simulations showing the airspeed of the tool of FIG. 1, with and without vanes, respectively;



FIG. 6 is a front view of the baffle of the tool of FIG. 1;



FIG. 7 is a perspective view of a second embodiment of a tool constructed in accordance with the teachings of the present disclosure;



FIG. 8 is an interior view of FIG. 7;



FIG. 9 is a side view of FIG. 7 where the baffle is in a blow mode position;



FIG. 10 is a side view of the tool, similar to FIG. 9, where the baffle is in a vacuum mode position;



FIG. 11 is a view of the interlock mechanism in the handle;



FIG. 12 is a front view of the interlock mechanism;



FIG. 13 is a perspective view of the control knob;



FIG. 14 is a perspective view of the control knob and switch; and



FIG. 15 is a perspective view of the switch.





Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.


DETAILED DESCRIPTION

With reference to FIG. 1 of the drawings, an outdoor power tool, preferably a blowervac, is constructed in accordance with the teachings of the present disclosure, and is generally indicated by reference numeral 10. The blowervac includes a main housing 12 having a handle 14 positioned on top and an airpipe 16 attached to a front portion of the main housing 12. The airpipe 16 is detachably connected to a sloped collar 18 of the housing 12.


At a rear portion of the main housing 12, is an air inlet 20 is covered by a grill 22. Adjacent the air inlet is an air exhaust 32. Inside the main housing 12, is a fan assembly with two sets of propellers, a rear propeller 26a and a front propeller 26b. A vane collar 28 (also shown in FIG. 4) is located forward of the front propeller 26b.


A baffle in the form of a flap 30 is hinged near the air inlet 20 and is movable between an upright position where it blocks the air inlet 20, and a down position (shown in dotted lines) where it blocks the air exhaust 32. It should be understood that the flap is shaped to completely block the air inlet 20 and air exhaust 32, and in the embodiment shown in FIGS. 1 and 6, is a non-planar generally circular shape.


The two propellers of the fan assembly are connected by a single drive axle 34, which is connected to a motor 36 via a transmission 38, which in the present embodiment is a direct belt drive. The motor 36 is located underneath the main housing 12 in a motor housing 40. The two propellers 26a and 26b are fixed on the single axle 34 and rotate together so that the motor 36 drives both propellers 26a and 26b simultaneously. However, it should be appreciated that other embodiments of the invention could incorporate any number of propellers, including a single propeller. Additionally, the transmission could use other mechanisms, including but not limited to, spur gears to transmit power.


In operation, the blowervac 10 can be operated either in a blowing mode or a vacuum mode. To convert between the two modes, the flap 30 is moved between the two positions, and the motor direction is changed. A switch 44, located in the handle 14, controls power to the motor 36. Either AC or DC power can be provided. The switch 44 is connected to the motor through electrical wiring that is routed through the main housing 12, which has an inner layer 12a and outer layer 12b to house the wiring (see FIG. 3).


In the blowing mode, the flap 30 is in the down position so that it covers the air exhaust 32. The motor rotates in a first direction where air is pulled in through the air inlet 20 and passes through the housing 12 to exit out of the airpipe 16. Because the air exhaust 32 is blocked by the flap 30, no air passes in this direction. Also, because the motor 36 is positioned outside of the main housing 12, eg. in the motor housing 40 below the main housing 12, the main housing's radial and longitudinal dimensions are reduced. Additionally, greater airflow efficiencies are achieved since the motor does obstruct the airflow path.


To further increase performance in the blowing mode, the vane collar 28 is positioned downstream of the fan assembly 24 and includes inwardly extending vanes 29 (see FIGS. 3 and 4) that helps reduce the turbulence in the airflow. FIGS. 5A and 5B show the airflow patterns with and without the vanes, respectively. More specifically, both figures show that the higher air speeds, the region labeled 46, are at the outer contours of the airpipe 16, and as you go towards the center, the region labeled 48, speed decreases. However, in comparing the figures, it's clear that the high air speed region 46 is larger with the vanes 29 (FIG. 5A) and then without (FIG. 5B).


Now, referring to FIG. 1, the internal diameter of the main housing 12 is larger than the airpipe 16. Turning to FIG. 3, it can be seen that the vanes 29 of the vane collar 28 extend inwardly so that their tips align with the circumference of the airpipe 16, without extending into the area defined by this boundary. This is done so that the vanes reduce airflow turbulence in the blow mode, while at the same time, not obstructing any debris collected during use in the vacuum mode, as explained in further detail below.


To switch to the vacuum mode, the flap 30 is moved to the upright position where it blocks the air inlet 20. This opens up the air exhaust 32 pathway. A mechanical lever (not shown) can be provided to move the flap 30 between the two positions, but any type of mechanism can be used. In a preferred embodiment, the lever also actuates a motor switch that reverses the motor direction so that air is pulled in through the airpipe 16. As debris is pulled into the main housing 12, it is mulched by the two propellers 26a and 26b. Referring to FIG. 2, an additional blender blade 42 can be included to help mulch debris pulled into the main housing 12. The blender blade 42 can be affixed to the axle 34 of the fan assembly. As the debris is mulched, it exits through the air exhaust 32 and into an attached collection bag 50.


As can best be seen in FIG. 3, the propellers 26a and 26b of the fan assembly 24 each include three blades 27a and 27b. The propellers 26a and 26b are rotationally offset from one another so that their blades 27a and 27b are equally spaced around the main housing 12. Alternatively, the propellers 26a and 26b can be aligned so that the blades of the rear propeller 26a are directly behind the blades of the front propeller 26b.


Referring now to FIG. 6, the flap 30 has a non-planar circular shape with scoops 31 on a top surface. The scoops 31 have a rounded curved shape that function to help move the flap into the proper position. When in the blowing mode (when the flap 30 is in the down position), air is pulled in through the air inlet 20 and push the flap 30 downward into the blowing mode position. The rear portions of the scoops 31 smoothly transition with the flap 30 so that air flowing over the flap is not disrupted.


Conversely, when in the vacuum mode, air is pulled through the airpipe 16. If the flap 30 were in the incorrect, down position, the scoops 31 would catch the air and help lift the flap into the upright vacuuming mode position. The front of the scoops have an “eyelid” like configuration designed to catch the airflow over the flap 30 to help lift it into the proper position.


Referring now to FIGS. 7-14, a second embodiment of the invention is shown. Similar parts to the prior embodiment will be designated with the same reference number. This second embodiment is similar to the first embodiment except for the way in which the tool converts from blowing mode to vacuum mode.



FIG. 7 shows a blowervac 100 having a main housing 112 with an airpipe 16, a handle 14 on the main housing 112, and a motor housing 40 for holding a motor 36. A rear portion 113 of the housing 112 includes an upper section having a series of vents or slots 114 that function as the air inlet 120, and a lower section with the exhaust 32.


Referring now to FIGS. 8-10, inside the rear portion 113 of the housing 112 is a baffle 122 in the form of a shroud that is rotatable 180 degrees from a blowing mode position where it covers the bottom half of the rear portion 113, to a vacuum mode position where is covers the top half of the rear portion 113.


In the blowing mode, shown in FIGS. 8 and 9, the baffle 122 covers a bottom section of the rear portion 113 so that it blocks the air exhaust 32. In operation, the fan assembly 24 pulls air in through the air inlet 120, which then travels past the fan assembly 24 and ultimately out of the airpipe 16.


In the vacuum mode, shown in FIG. 10, the baffle 122 is rotated so that it covers a top section of the rear portion 113 to block the vents 114. The motor 36 and fan assembly 24 operate in reverse and pulls air in through the airpipe 16, past the fan assembly 24 and out through the air exhaust 32. Like in the previous embodiment, a bag may be attached to air exhaust 32 to catch and collect any debris.


A knob 124 is mechanically connected to the baffle 122 to rotate it between its two positions. A lock-out mechanism is shown in FIGS. 11-13, which prevents the knob from rotating while the tool is in operation. First, referring to FIG. 11, a power switch 125 is located on the handle 14, and a flexible band 126 is fixedly secured to the switch 125. The switch 125 slides forward and backward between three positions; an off position (which is the furthest forward), a low power position (middle position), and a high power position (furthest rearward).


As the switch 125 is moved, a free end 126a of the band 126 moves into and out of a slot 128a in the knob 124. This is best shown in FIG. 12. When the switch 125 is in the off position, the free end 126a of the band 126 is completely removed from the slot 128a, and so the knob is free to rotate. When the switch 125 is slid into the low power position, the band 126 moves slightly downward so that it is halfway into the slot 128a. Similarly, if the switch 125 is moved into the high power position, the band 126 moves completely into the slot 128a. In the low and high power position, the band 126 prevents the knob 124 from rotating.


Also, because the knob 124 can be turned 180 degrees from a blow mode to a vacuum mode, a second slot 128b is provided opposite the first slot 128a. The interaction of the band 126 with the second slot 128b is similar to that of the first slot 128a, allowing the interlock to work in either operating modes.


As mentioned previously, the knob 124 converts the tool from a blow mode to a vacuum mode by moving the baffle 122 between its two positions. Concurrently, the knob 124 automatically reverses the motor 36 direction to correspond to the operational mode. For instance, in the blow mode when the baffle 122 is covering the air exhaust 32, the motor 36 drives the fan assembly 24 in a first direction to blow air out of the airpipe 16. In the vacuum mode when the baffle 122 is covering the vents 114, the motor 36 drives the fan assembly in a second direction to suck air into the airpipe 16.


This automatic reversing of the motor direction is performed by a switch 130, as best shown in FIGS. 14 and 15. The switch 130 includes a pin 132 that sits within an upwardly curved groove 134 in the switch 130. An interior face of the knob 124 includes a semi-circular channel 136 that corresponds with the pin 132.


When the knob 124 is rotated, the pin 132 rides within the channel 136 until the end of the channel, either endwall 136a or 136b, engages the pin 132 and pushes it into one of the end positions in the groove 134. For example, in FIGS. 14 and 15, the pin 132 is positioned in the rightmost part of the groove 134, which is the blow mode so that the motor operates in a first direction. When converting to the vacuum mode, the knob 124 is turned counterclockwise. The pin 132 rides within channel 136 until the endwall 136b contacts the pin 132 and pushes it to the opposite end of the groove 134. This reverses the motor direction so that it is operating in the second direction, which is the vacuum mode for the tool. The operation to switch the tool to the blow mode is similar except in the reverse direction.


The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. By way of example only, the knob, interlock mechanism, and motor reversing switch shown in the embodiment of FIGS. 7-15 may be incorporated into the embodiment of FIGS. 1-6. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

Claims
  • 1. An outdoor power tool comprising: a housing having a fan assembly;an airpipe connected to a front portion of the housing;a motor operatively connected to the fan assembly, the motor capable of driving the fan assembly in a first blow mode to blow air out of the airpipe, and a second vacuum mode to suck air in through the airpipe.
  • 2. The outdoor power tool of claim 1, wherein the axis of the fan assembly is parallel with the longitudinal axis of the airpipe; and further comprising an air inlet at a rear portion of the housing capable of pulling air into the housing when operating in the blow mode.
  • 3. The outdoor power tool of claim 2, further comprising an air exhaust capable of exhausting air out of the housing when operating in the vacuum mode.
  • 4. The outdoor power tool of claim 3, further comprising a baffle moveable between a first position where it covers the air exhaust and a second position where it covers the air inlet, such that when the baffle is in the first position, the tool is operating in the blow mode, and when the baffle is in the second position, the tool is operating in the vacuum mode.
  • 5. The outdoor power tool of claim 4, wherein moving the baffle from the first position to the second position automatically reverses the direction of the fan assembly.
  • 6. The outdoor power tool of claim 4, wherein the baffle is in the form of a flap that is pivotable between the first position and the second position.
  • 7. The outdoor power tool of claim 6, wherein the flap includes at least one scoop to help maintain the flap in the proper position.
  • 8. The outdoor power tool of claim 4, wherein the baffle is in the form of a shroud that is rotatable between the first and second position.
  • 9. The outdoor power tool of claim 8, further comprising a knob for rotating the shroud, and an interlock mechanism for preventing the rotation of the shroud while operating the tool.
  • 10. The outdoor power tool of claim 9, further comprising a power switch for turning the tool on and off; and wherein the interlock mechanism includes a band having a first end fixedly connected to the power switch and a second end engageable with a slot in the knob when the power switch is in the on position to prevent the rotation of the knob.
  • 11. The outdoor power tool of claim 1, wherein the motor is located outside the main housing and is connected to the fan assembly through a transmission.
  • 12. The outdoor power tool of claim 1, wherein the main housing includes vanes downstream from the fan assembly to reduce the turbulence of the airflow.
  • 13. An outdoor power tool comprising: a housing having a fan assembly therein;a motor connected to the fan assembly to drive it in a first direction and a second reverse direction;an airpipe connected to a front portion of the housing;a rear portion of the housing having an air inlet and an air exhaust; anda baffle inside the housing movable between a first position covering the air exhaust, and a second position covering the air inlet.
  • 14. The outdoor power tool of claim 13, wherein an axis of the fan assembly is parallel to a longitudinal axis of the airpipe.
  • 15. The outdoor power tool of claim 13, wherein when the baffle is in the first position, the tool operates in a blow mode where air enters the tool through the air inlet and exits the tool through the airpipe, and when the baffle is in the second position, the tool operates in a vacuum mode where the air enters the tool through the airpipe and exists the tool through the air exhaust.
  • 16. The outdoor power tool of claim 15, wherein the baffle is in the form of a shroud inside the rear portion of the housing, and a knob mechanically linked to the shroud to rotate it between the two positions.
  • 17. The outdoor power tool of claim 16, further comprising a power switch for actuating the tool, and an interlock mechanism preventing the rotation of the knob when the tool is actuated.
  • 18. The outdoor power tool of claim 15, wherein the motor is located outside the housing and is connected to the fan assembly through a transmission.
  • 19. The outdoor power tool of claim 15, where the baffle is in the form of a flap that is pivotable between the first position and second position.
Provisional Applications (1)
Number Date Country
62158265 May 2015 US