An in-line blower having a housing with a substantially straight airflow path. A motor and fan are positioned within the airflow path, below the handle of the blower. A battery powers the motor, and is located below the housing so that the handle, motor and fan, and the battery are vertically aligned so the weight of the blower is aligned with the handle, and reduces moment forces acting thereon.

FIELD

The present disclosure relates to blowers, specifically axial-fan or in-line type blower 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, thereby increasing airflow efficiencies.

An example of such a design is shows in U.S. Pub. No. 2012/0076672, which shows a blower having an air inlet opening13, an axial blower or fan6and an outlet opening15that are, for the most part, linearly aligned so as to reduce any curves which may impede airflow. For cordless or battery powered blowers, the battery is often located at the rear of the blower where the air intake exists, and so this presents an issue since the battery must be moved so as not to obstruct the air intake.

Another example of an in-line blower is shown in US Pub. No. 2013/0239361, where the battery is not attached to the blower, but rather placed on a user's back. This design requires a harness to secure the battery to the user's back and requires an electrical cable which between the battery and blower, which can get tangled or otherwise impede the user's movement.

Yet another example is U.S. Pat. No. 4,884,314 where the batteries are integrally secured in the handle of the blower. This design has the disadvantage of not having a removable battery, which is desirable for charging and continuous use with multiple batteries.

Accordingly, there remains a need in the art for an in-line blower that is comfortable and easy to use.

SUMMARY

In one form, the present teachings provide a blower that includes an electric motor, a rotatable fan driven by the electric motor, a handle, a battery, and an airflow tube. The airflow tube is generally straight so that the airflow through the blower does not undergo any significant change in direction. Additionally, the handle, motor and fan are vertically aligned so that the center-of-gravity of the blower is below with the handle, reducing any moment forces on the user.

In another form, the blower includes a battery housing surrounding the battery to protect it from damage. The battery housing can be used to support the blower when placed on the ground or other surface, further protecting the blower housing from scuffing damage.

In yet another form, the battery housing can be secured to the blower housing at an angle so that it's resting position on the ground is identical to the in-use position so that a user can immediately use the blower when picked up without having to readjust his grip.

DETAILED DESCRIPTION

With reference toFIGS. 1, 2 and 2Aof the drawings, a blower constructed in accordance with the teachings of the present disclosure is generally indicated by reference numeral10. The blower includes blower housing12, a handle14positioned above the housing12, and an air intake grill16at the rear of the housing12. The housing12surrounds an airflow tube18which directs the airflow through the blower. The airflow tube18has a first end or inlet end18A (shown inFIG. 2A) at the rear of the blower and is covered by the air intake grill16. The airflow tube18has a second end or exhaust end18B at a front end through which air exits the blower (shown inFIG. 2). A battery housing20is attached to the bottom of the housing and holds a battery22.

Referring now toFIG. 2A, the battery22is electrically connected to a motor24, positioned inside the blower housing12, to deliver energy to the motor and drive fan25. The fan25pulls air in through the air intake grill16, through the fan25, around the motor24and out through the exhaust end18B of the airflow tube18. As shown, airflow tube18is a substantially uniform body and provides a linear air path along the longitudinal direction of the blower, generally defined by the x-axis. The motor24and fan25are positioned within the airflow tube18in the path of the airflow so that their axes are parallel to the longitudinal axis of the blower. The tube18can be formed from a single integral body, or may be formed from several parts that are combined to form the body.

The blower includes a variable speed trigger26having a logic level switch27. The switch is connected to a PCB29and the trigger distance determines the level of output from the switch, for example 0V-5V, that is then translated by the PCB29to output a corresponding voltage range to the motor24, for example 0V-20V, that varies the speed of the motor24, and consequently, controls the air speed through the blower. A speed lock28can mechanically lock the trigger26at a set speed to relieve the user from continually holding the trigger26in position.

Referring toFIG. 2A, the motor24and fan25are placed in the housing12below the handle14. Additionally, the battery22is placed generally below the motor24so that the heaviest components of the blower are vertically aligned and the center-of-gravity (CoG) (as shown inFIG. 2) of the blower is directly below the handle14. Having the CoG aligned with the handle provides many advantages. First, when the blower is held at a user's side, the weight of the blower is in line with the user's arm so that there is no moment acting on the user's hand. In other words, the blower does not tend to tip forward or backward, and so the user does not have to exert any force to keep the blower level or otherwise in position.

Second, since the weight of the unit is centered at the handle, this also reduces the force required to turn the blower side-to-side (rotate about the y-axis), as illustrated inFIG. 3. And third, the battery22acts as a ballast helping to maintain the blower in position in both the lateral direction (as shown inFIG. 4) and longitudinal direction.

In reference toFIG. 5, additional benefits of the arrangement of the handle14, fan25, motor24, and battery22are seen. In addition to having the component vertically aligned, it is desirable to have the fan25as close to the handle14as possible to reduce any moment forces that are produced by the air exiting the airflow tube18(eg. the blower would tend to want to go backward in the user's hand). So for example, arrangement A is preferable over arrangement B, because when the fan25is operating, the air blowing out of the airflow tube18creates a moment partially determined by the distance between the handle and the fan25. The greater this distance, the larger the moment forces created, which must be opposed by the user to maintain the blower in position. The distance A is less than distance B, and so produces small forces on the handle14. Additionally, these same forces make it more difficult to control the blower when rotating it about the y-axis (seeFIG. 3).

Now referring toFIGS. 1 and 4, the battery housing20is molded from a durable plastic, for example glass-filled polypropylene, and attached to the housing12to support the blower when placed on the ground. The battery housing20is designed to withstand drops and endure daily wear and tear from being scraped and banged on the ground or other surface. The battery housing20includes a top wall, side walls, and a foot portion30that extends outwardly to provide a larger support surface for the blower.

Now referring toFIG. 6, it can be seen that the longitudinal axis of the blower housing12and the airflow tube18, as identified by the x-axis, is at an angleθ1relative to the ground surface32when the blower10is sitting on the ground. The angleθ1is between 3-10 degrees, and in a preferred embodiment is approximately 5.6 degrees. Also, the longitudinal axis of the handle, as identified by h, is at an angleθ2relative to the longitudinal axis x of the blower housing. The angleθ2is between 15 and 25 degrees, and in a preferred embodiment is 20.5 degrees.

The angle of the blower housing12and handle14are such that the blower10is automatically in an in-use position when picked up by a user. This can be seen inFIG. 7A, where the angle of the blower housing12and airflow tube18are substantially similar in the in-use position held by the user, and when on the ground. Contrast this withFIGS. 7B-7D, which show examples of prior art units, where the angles of the exhaust tube are significantly different when sitting on the ground compared to the in-use position in the user's hand. This requires the user to then readjust his grip to get the blower in the proper position.

An alternative embodiment of the blower is shown inFIG. 8where similar components are labeled with the same reference number. Here the electric blower does not require a battery and can be powered by alternative means, such as a power cord (not shown) attached to an outlet.

Here, the motor24has been moved out of the airflow tube18and positioned below the housing12. The motor24is secured within a motor housing40below the main housing12, or alternatively, the motor housing40can be formed integrally and as part of main housing12. The motor24has a drive shaft42that is connected to a first end of a belt-drive or pulley system34. The pulley system34is enclosed in a transmission casing44, with a drive belt46therein, that connects the drive shaft42of the motor with a drive shaft48of the fan25. In this way, rotation of the motor drive shaft42is transferred to the fan25. In a preferred embodiment, the ratio of the pulley system is 1:1, but it should be understood that other ratios can be utilized.

The removal of the motor24out of the airflow tube18allows a larger motor to be used, since it won't be limited by the diameter of the airflow tube18. Using larger motors, while maintaining fan size, and/or tube dimensions allows an optimized design for maximum airflow efficiency. This design also maintains the weight balance of the previous embodiment with the motor24acting as a ballast, helping to stabilize the blower when in use, similar to that described in the previous embodiment.