Blower with cruise control and boost function

A blower may (100) include a power unit and fan assembly powered by the power unit, a stepless trigger (146), control circuitry configured to at least partially control application of power to drive the fan assembly based on a position of the stepless trigger (146), and one or more buttons. The fan assembly may rotate at a speed proportional to the position of the stepless trigger (146) in a first mode of operation. The control circuitry may be configured to enable the operator to actuate a first button (164) of the one or more buttons to shift to a second mode of operation in which speed of the fan assembly is not proportional to the position of the stepless trigger (146) over at least a portion of a range of motion of the stepless trigger (146).

TECHNICAL FIELD

Example embodiments generally relate to outdoor power equipment and, more particularly, relate to a cruise control and boost function for power equipment such as a blower.

BACKGROUND

Outdoor power equipment includes such devices as mowers, trimmers, edgers, chainsaws, blowers, and the like. Although powering such devices could be accomplished in any number of ways, these devices are often powered by a gas engine or electric motor. The engine or motor connects to the shaft of a tool, such as a cutting blade or fan assembly, which spins to perform useful work. The operator can precisely control the engine or motor speed by manipulating a stepless trigger, thereby selectively controlling the application of power to the engine or motor as needed.

During operation, the operator may frequently wish to fix the speed of the engine or motor. For example, when mowing a lawn of uniform grass length or blowing off a driveway, the operator may wish to bring the motor or engine up to the desired speed and then use cruise control to maintain that speed for consistent results. For this purpose, gas or petrol blowers typically employ a cruise control function that is mechanically implemented to maintain engine or motor speed above or around a desired level. In particular, such functions may hold engine speed at a fixed RPM by blocking the trigger control mechanically in a fixed position with a lever that the user can operate. On electric motors, buttons with various steps are defined so that a discrete speed change is associated with each step. Thus, a desired speed can be achieved by proceeding to the corresponding desired step.

To improve operational control of the blower, it may be desirable to provide control functions that can limit the rotational speed of the motor in an easy and intuitive way and also provide a speed boost when desired.

BRIEF SUMMARY OF SOME EXAMPLES

An example embodiment of a blower may include a power unit and fan assembly powered by the power unit, a stepless trigger, control circuitry configured to at least partially control application of power to drive the fan assembly based on a position of the stepless trigger, and one or more buttons. The fan assembly may rotate at a speed proportional to the position of the stepless trigger in a first mode of operation. The control circuitry may be configured to enable the operator to actuate a first button of the one or more buttons to shift to a second mode of operation in which speed of the fan assembly is not proportional to the position of the stepless trigger over at least a portion of a range of motion of the stepless trigger.

In another embodiment, a method of operating a blower may be provided. The method may include manipulating, during a first mode of operation, a stepless trigger to accelerate the blower motor to a desired rotational speed that is proportional to a position of the stepless trigger, and pressing a first button to shift to a second mode of operation in which an upper speed limit for the motor is set, but rotational speed remains proportional to the position of the stepless trigger below the upper speed limit. The method may further include pressing a second button to temporarily increase motor speed to a predefined maximum speed for a predefined period of time.

The boost button may be the same or different from the button used to activate the cruise control. The boost function can be activated independently of or in combination with the cruise control function. Additionally, the keypad may contain light-emitting diode (LED) indicators that illuminate to indicate the status of each keypad function.

DETAILED DESCRIPTION

In some cases, an operator of a blower may wish to use a cruise control function to set a limit on motor speed in order to avoid blowing up too much dust in the air, to save power, or to achieve the peak operating efficiency of the engine or motor. In addition, an operator that encounters thick weeds while mowing or wet or sticky substances while blowing might want to temporarily increase the engine or motor speed to power through these difficult areas. Accordingly, it may be desirable to have a temporary increase in engine or motor speed that is easy to implement but also prevents prolonged operation at increased speed that could overload the blower or empty the battery too fast.

FIG. 1illustrates a side view of a blower100in accordance with an example embodiment. It should be appreciated that the blower100merely represents one example of power equipment on which an example embodiment may be employed. Referring toFIG. 1, the blower100may include a housing110inside which various components of the blower100are housed. The blower100may further include a motor, engine, or power unit for providing the driving force to move air through the blower100. In some embodiments, the power unit may be a three phase electric motor that is operated under the control of a control unit or control circuitry and powered by a battery or battery adaptor. However, a DC motor could be used in some embodiments as well, as could a gas engine or another power unit. In this embodiment, the motor is housed in the motor housing portion120, which is adjacent to the blower tube150.

The housing110may be formed of plastic, composite materials, metals, or any other desirable materials of sufficient rigidity. In an example embodiment, the housing110may be formed of two or more molded pieces that can be fit together. In some cases, the molded pieces may form half-shells (e.g., right and left half-shells) that can be affixed to each other via welding, adhesives, snap fittings, fixing members (e.g., screws), and/or the like. When molded pieces are fit together, they may form a seam at the location of joining between the molded pieces.

In some embodiments, the control unit or control circuitry may be housed in its own portion of the housing110. The portion of the housing110in which the control unit is housed may be referred to as a control unit housing portion132, and the control unit housing portion132may be an integral part of a half-shell (as described above) or may be a separate housing portion that is joined to other housing portions. As shown inFIG. 1, the control unit housing portion132may be disposed at a forward portion of the housing110.

In an example embodiment, the battery may be housed in a battery compartment142that may be disposed at a rear portion of the housing110, separated from the control unit housing portion132by a handle144. The handle144may be formed by extending between a distal end of the control unit housing portion132to a top portion of the battery compartment142. Thus, the handle144may extend above the motor housing portion120. In some embodiments, an aperture or gap may be formed in the housing110by the handle144to enable the operator's hand to extend around the handle144. The aperture may be referred to as a handle aperture145.

The handle144may include a stepless trigger146that may be operated by a finger of the operator while the operator holds the handle144. Actuation of the stepless trigger146may cause power from the battery to be selectively applied to the motor to turn the motor based on control provided by the control unit. In some cases, the control unit may include interlocks, protective functions, or other control mechanisms that may sense various conditions of the blower100via sensors, switches, or other mechanisms in order to selectively control the application of power to the motor based on indications of user intent (e.g., via actuation of the stepless trigger146) and/or determinations regarding the state of the blower100as provided by the sensors, switches, or other mechanisms. As can be seen fromFIGS. 1 and 2, the stepless trigger146extends downward from the handle144into the handle aperture145.

It should be appreciated that althoughFIG. 1shows an example in which the stepless trigger146is used for selective powering of the motor, other example embodiments may employ a selector, switch, button, or other such operative member in order to selectively control operation of the motor. Thus, for example, on/off, speed control, or other operable functions for controlling the motor may be performed using an operative member of any desirable form, and the stepless trigger146is just one example.

The blower100may further include a blower tube150that is attached to housing110(or is a part of the housing110) and through which air may be expelled. The blower tube150may include an inlet portion and an outlet156. The outlet156may be at a distal end of the blower tube150and the inlet portion may be at an opposite end of the blower tube150proximate to the motor and the battery. In an example embodiment, the inlet portion may be disposed proximate to an aperture array158including louvers, vanes, guide holes, or other such apertures formed in the housing110to enable air to enter into the blower tube150responsive to operation of the motor to be expelled via the outlet156. In this regard, the operation of the motor may cause an impeller or fan assembly to rotate so that a low pressure area is generated to draw air into the inlet portion through the aperture array158to be passed through the fan assembly and expelled from the blower tube150at the outlet156to blow leaves, debris, or any other material. In some cases, the louvers, vanes, guide holes, or other such apertures formed in the housing110to embody the aperture array158may be strategically located to reduce the ability of noise from the motor or airflow in the blower tube150from transmitting up to the operator's ears. Moreover, the louvers, vanes, guide holes, or other such apertures of the aperture array158may be formed on each respective side portion of the housing110as shown inFIG. 1.

An example embodiment of a blower100may therefore include a housing110that encloses the internal components, such as a motor, fan assembly, control circuitry, and battery. The housing110can define a handle portion144with handle aperture145, and the fan assembly may be operably coupled to the blower tube150to force air through the blower tube150responsive to operation of a motor. As the operator compresses the stepless trigger146, the motor speed may increase in proportion to the amount of compression. Thus, the operator may increase speed by more fully compressing the stepless trigger146. Then, when a desired motor speed and corresponding airflow level through the blower is achieved, the operator may select to implement a cruise control function using a keypad in accordance with an example embodiment.

As shown inFIGS. 2 and 3, an exemplary embodiment may have a control keypad160located on top of the blower housing110toward the forward end of the handle144. The keypad160, which is described in more detail below, provides for easy operation or control of the blower either in conjunction with, or independently of, the stepless trigger146. The keypad160may contain one or more buttons (162,164, and166) that may be manipulated easily by the operator. Of note, the keypad160may interface with processing circuitry that may include a processor and memory, where various instructions, applications and/or the like are stored in the memory and executed by the processor. Various functions described herein may therefore be implemented by operation of the processing circuitry to direct or cause the corresponding functionality to be performed responsive to execution of stored instructions for performing (when executed) the same.

FIG. 4shows an exemplary embodiment of the keypad160, which contains three buttons for controlling the blower. The “ON” button162, or power button, starts and stops the blower; the “C” button164(i.e., a first button) activates the cruise control function; and the “B” button166(i.e., a second button) activates the boost function. The keypad also has one or more indicators168, which are preferably light-emitting diodes (LEDs) that illuminate when the blower is on or when the function associated with the indicator is activated, thereby showing the operator the operational status of the blower.

In operation, the operator reaches the required airflow for a certain task by manipulating the stepless trigger146. When a sufficient airflow is achieved the operator can press the cruise control button164which sets the maximum speed for the motor relevant to the blower airflow. When the cruise control is activated, the associated LED indicator168is illuminated and the speed limit is set in memory until the cruise control is deactivated and the stepless trigger146is released. The cruise control function prevents the motor speed from exceeding this maximum speed limit no matter how far the stepless trigger146is pressed. Thus, for example, the operator could simply completely compress the stepless trigger146and not have to worry about trying to maintain a certain level of tension or compression. However, lower motor speeds are still possible by relaxing the compression level below the maximum speed limit setpoint. The operator can deactivate the cruise control and regain normal trigger-control of the blower by simply pressing the cruise control button164again. Turning the blower off (e.g., by pressing the power button162) or removing the battery also resets the cruise control function and the speed limit.

A boost function may also be activated by the keypad160. In the exemplary embodiment, the boost function is controlled by a separate button (e.g., B button166). However, the boost function could be alternatively activated using the same button as the cruise control, for example, by holding the button down for a different amount of time as compared to the cruise control function, or by providing a specific pattern of actuation (e.g., a double press, etc.). The boost function may be activated when the stepless trigger146is pressed at least some prescribed amount, for example, 10% of the full trigger position, or when the cruise control is activated. When the boost function is activated, the motor spins up to a maximum (or predeteermined) speed for a predefined time (e.g., five seconds) giving the user an increased airflow and airspeed (i.e., power). This boost function could be used, for example, to remove sticky or wet objects from a surface. To save battery time and prevent overheating of components, the use of this function may be limited over time, for example, such that the five-second boost is only available once every thirty seconds.

The boost function can be used in combination with, or independently of, the cruise control function. The cruise control is a very convenient solution when it is desirable to save power or to limit the total airflow to prevent blowing up too much dust in the air. By using the boost function, it is possible to have a high airflow for a short time to, for example, remove things that are stuck to the ground without overloading the blower or emptying the battery too fast.

It should be appreciated that although the keypad160is located on top of the handle in the exemplary embodiments discussed above, it could instead be located anywhere on the blower housing110that provides for easy user input and function selection. For example, the keypad160may be located on the underside or side of the handle144, in the handle aperture145or on the stepless trigger146itself. Furthermore, the control buttons need not be confined to a single keypad or panel at all, but may instead be placed as individual buttons on the blower housing110. However, by locating the keypad160on the forward end of the handle144and placing all buttons (162,164, and166) on the keypad160along with their respective LED indicators168, operators can conveniently manipulate the keypad buttons without otherwise adjusting their grip and the LED indicators168remain readily visible during operation.

Accordingly, a blower of an example embodiment may include a power unit and fan assembly powered by the power unit, a stepless trigger, control circuitry configured to at least partially control application of power to drive the fan assembly based on a position of the stepless trigger, and one or more buttons (e.g., on a keypad). The fan assembly may rotate at a speed proportional to the position of the stepless trigger in a first mode of operation. The control circuitry may be configured to enable the operator to actuate a first button among the one or more buttons (e.g., on the keypad) to shift to a second mode of operation in which speed of the fan assembly is not proportional to the position of the stepless trigger over at least a portion of a range of motion of the stepless trigger.

In some cases, the features above may be modified, augmented or amplified in various optional ways. For example, in some cases, the second mode may be entered by activating a cruise control function responsive to actuating a cruise control button on the keypad, thereby setting an upper speed limit for the fan assembly that is equal to a speed of the fan assembly when the cruise control function was activated. In some embodiments, the operator may be enabled to deactivate the cruise control function by pressing the cruise control button again. In an example embodiment, the operator may be enabled to activate a boost function by pressing a button on the keypad, thereby causing the fan assembly to accelerate to a maximum speed. In some cases, the boost function may be limited to enable activation only once in a predefined time interval. In some embodiments, the boost function may be limited to enable activation for a predefined duration of time. In some examples, the predefined duration of time is about five seconds and the predefined time interval is about thirty seconds. In an example embodiment, the button may be the first button or it may be a different button. When the button is the first button, a single actuation of the first button may shift the device to the second mode of operation (i.e., the cruise control function), and a double actuation of the first button may cause the device to shift to a third mode of operation (i.e., the boost function). In some embodiments, the boost function is enabled to be activated only after the stepless trigger has been pressed a predefined amount (e.g., at least about 10%). In some cases, the boost function is enabled to be activated independent of the cruise control function, but in others it is enabled to be activated responsive to prior activation of the cruise control function. In an example embodiment, light-emitting diode (LED) indicators located on the keypad may indicate a mode of operation of the blower.