FIELD OF THE INVENTION

The present invention relates to a portable leaf blower and more particularly to a portable leaf blower according to the preamble of claim 1.

BACKGROUND OF THE INVENTION

A leaf blower is a gardening tool that propels air out of a tube to move yard debris, such as leaves. Leaf blowers typically comprise a power source, such as an internal combustion or electric motor, driving a blower that in turn exhausts air under pressure out of the tube. The air flow discharging from the tube is directed to a desired location and direction by a user for moving leaves or other garden material.

One of the problems associated with the prior art leaf blowers is that controlling the moving direction of yard debris, such as leaves, is difficult after the air flow has encountered the yard debris. When the air flow leaving from the leaf blower encounters the yard debris, the yard debris receives movement energy from the air flow and starts to move in uncontrolled manner. This makes working with the leaf blower difficult and time consuming.

BRIEF DESCRIPTION OF THE INVENTION

An object of the present invention is to provide a portable leaf blower such that the prior art disadvantages are solved or at least alleviated.

The objects of the invention are achieved by a portable leaf blower which is characterized by what is stated in the independent claim 1. The preferred embodiments of the invention are disclosed in the dependent claims.

The invention is based on the idea of providing a portable leaf blower comprising a blower unit arranged to be carried by a user. In other words, the portable leaf blower according to the invention is arranged to be carried by the user and comprises the blower unit which can be carried as a backpack, or as a portable device carried in front of the user, or as a handheld device, or any other kind of portable device. The blower unit is arranged to generate an air flow to be discharged out of the portable leaf blower. The portable leaf blower also comprises an air discharge unit for discharging the air flow generated in the blower unit out of the portable leaf blower. The air discharge unit comprises a discharge tube and a branching unit arranged in a flow communication with the discharge tube. The discharge tube extending from the blower unit and having a distal end and a proximal end. The distal end of the discharge tube being connected to the blower unit. The branching unit comprising a first output tube having a first outlet opening, and a second output tube having a second outlet opening, the first output tube and the second output tube are arranged in connection with the discharge tube such that the air flow coming from the discharge tube is divided into a first output air flow discharging from the first output tube through the first outlet opening out of the portable leaf blower, and a second output air flow discharging from the second output tube through the second outlet opening out of the portable leaf blower.

In other words, the air discharge unit comprises a discharge tube and a branching unit between which there is a flow communication. The flow communication means that the air flow can flow through the parts, on this occasion between the discharge tube and the branching unit, in the flow connection. The air flow generated in the blower unit is discharged through the discharge tube to the branching unit and through the branching unit out from the portable leaf blower. The branching unit has a first output tube and a second output tube such that the air flow coming through the discharge tube is divided between the output tubes.

According to the invention the branching unit extending away from the proximal end of the discharge tube, and the first outlet opening of the first output tube and the second outlet opening of the second output tube are arranged at a distance from the proximal end of the discharge tube.

In other words, the branching unit is connected to the discharge tube such that the branching unit extends from the proximal end of the discharge tube. The branching unit extends away from the discharge tube such that the outlet openings of the first output tube and the second output tube are at a distance away from the discharge tube. That is, the first and second output tubes have a length, and the outlet openings are arranged at this length from the discharge tube. The first and second outlet openings are spaced apart because they are located at the ends of the output tubes and the output tubes are spaced apart. The first and second output tubes may be separate output tubes that are connected separately to the discharge tube or the first and second output tubes may have a connection to each other directly or through an intermediate piece such as a branch adapter which is discussed later.

According to the invention the first output tube comprises a first inlet opening for the air flow to flow from the discharge tube into the first output tube, and the second output tube comprises a second inlet opening for the air flow to flow from the discharge tube into the second output tube. The branching unit is connected to the discharge tube such that the air flow is arranged to flow directly from the discharge tube through the first inlet opening to the first output tube and through the second inlet opening to the second output tube.

In other words, the first output tube and the second output tube are directly connected to the discharge tube such that the air flow flows directly from the discharge tube to the first and second output tubes. Therefore, the first output tube has a flow connection with the discharge tube, and the second output tube has a flow connection with the discharge tube, but the first and second output tubes are not in a direct flow communication with each other.

According to the invention the branching unit comprises a branch adapter arranged between the discharge tube and the first and second output tubes. The branch adapter forming a common inlet opening for the first output tube and the second output tube for the air flow to flow from the discharge tube to the branching unit.

In other words, the branch adapter forms a common inlet for the first and second output tubes. The first and second output tubes may be integrally formed with the branch adapter, and the branch adapter may be, for example, a base of a U-shaped branching unit from which the branches of the U leave. The branches of the U are then the first and second outlet tubes. Therefore, the branch adapter may be integrated with the first and second output tubes so that the branch adapter itself does not exist but is a part that connects the first and second output tube together without the tubes being separately and directly attached to the discharge tube. In other words, the first and second output tubes are then together connected to the discharge tube with a common inlet opening.

According to the invention the branching unit comprises a branch adapter arranged between the discharge tube and the first and second output tubes, the branch adapter having a common inlet opening providing the flow communication from the discharge tube to the branching unit, a first connecting outlet opening providing the flow communication from the branch adapter to the first output tube through a first inlet opening of the first output tube, and a second connecting outlet opening providing the flow communication from the branch adapter to the second output tube through a second inlet opening of the second output tube.

In other words, the branch adapter separately comprises a common inlet opening for the discharge tube and separate connecting outlet openings to the first and second output tubes. The common inlet is preferably arranged in the flow direction separately from the connecting outlet openings.

According to the invention the branch adapter is formed integrally with the first and second output tubes.

Formed integrally means that the branch adapter cannot be separated from the first and second output tubes without breaking the branching unit.

According to the invention the branch adapter is removably arranged between the discharge tube and the first and second output tubes.

In other words, the branch adapter can be separated from the connection between the discharge tube and from the connections between the first and second output tubes.

According to the invention the branching unit comprises an adjustment element arranged to adjust an orientation of the first output tube such that a flow direction of the air flow discharging out from the first outlet opening is adjustable. Alternatively, the branching unit comprises an adjustment element arranged to adjust an orientation of the second output tube such that a flow direction of the air flow discharging out from the second outlet opening is adjustable. Alternatively, the branching unit comprises at least one adjustment element arranged to adjust an orientation of the first output tube and the second output tube such that flow directions of the air flows discharging out from the first outlet opening and the second outlet opening are adjustable.

In other words, the adjustment element is arranged to the branching unit such that the orientation of the first output tube, or the orientation of the second output tube, or the orientation of the first output tube and the second output tube can be changed which means that the flow direction of the air flow discharged through the outlet openings can be directed to a desired direction. The orientation of the output tubes and the placement of the outlet openings relative to the discharge tube is therefore adjustable.

According to the invention the adjustment element is a hinge, or a joint arranged to adjust the orientation of the first output tube and/or the second output tube of the branching unit relative to each other.

In other words, the adjustment element being a hinge, or a joint allows the first and/or second output tube be moved relative to the discharge tube. Alternatively, or in addition the adjustment element can allow only part of the first output tube, and/or only part of the second output tube to be moved relative to the rest of the first output tube and/or the second output tube.

According to the invention the adjustment element is provided to the first output tube, or the adjustment element is provided to the second output tube, or the adjustment element is provided to the first output tube and the second output tube.

According to the invention the first output tube comprises an adjustable structure so that its orientation relative to the discharge tube can be changed. Alternatively, the second output tube comprises an adjustable structure so that its orientation relative to the discharge tube can be changed. Alternatively, the first output tube and the second output tube comprise an adjustable structure so that their orientation relative to the discharge tube can be changed.

In other words, the adjustable structure can be such that the output tube can be bent or otherwise pivoted without a separate adjusting element.

According to the invention at least part of the first output tube having a flexible structure such that the orientation of the first output tube relative to the discharge tube is adjustable for adjusting a flow direction of the air flow discharging out from the first outlet opening. Alternatively, at least part of the second output tube having a flexible structure such that the orientation of the second output tube relative to the discharge tube is adjustable for adjusting a flow direction of the air flow discharging out from the second outlet opening. Alternatively, at least part of the first output tube and at least part of the second output tube having a flexible structure such that the orientation of the first output tube and the second output tube relative to the discharge tube are adjustable for adjusting a flow direction of the air flows discharging out from the first outlet opening and the second outlet opening.

In other words, the structure of the output tubes can be flexible such that the orientation of the output tubes can be adjusted.

According to the invention the first output tube comprises a surface structure in connection with an inner surface of the first output tube for changing the movement of the air flow coming from the discharge tube to the first output tube before discharging from the first outlet opening. Alternatively, the second output tube comprises a surface structure in connection with an inner surface of the second output tube for changing the movement of the air flow coming from the discharge tube to the second output tube before discharging from the second outlet opening. Alternatively, the first output tube comprises a surface structure in connection with an inner surface of the first output tube for changing the movement of the air flow coming from the discharge tube to the first output tube before discharging from the first outlet opening, and the second output tube comprises a surface structure in connection with an inner surface of the second output tube for changing the movement of the air flow coming from the discharge tube to the second output tube before discharging from the second outlet opening.

In other words, the inner surface of the first output tube and/or the second output tube has a surface structure which guides the air flow coming through the output tube so that it changes compared to a situation where the inner surface is smooth without having any specific surface structure. The air flow can be changed with the surface structure such that the flow direction changes, or turbulence or vortices are created in the air flow.

According to the invention the surface structure is a vortex groove structure generating a vortex to the first output air flow discharged through the first output tube or to the second output air flow discharged through the second output tube or to the both first and second air flows.

In other words, the surface structure comprises for example grooves or protrusions which form grooves in such a way that the structure causes the air flow to vortex as it exits through the outlet openings.

According to the invention the blower unit comprises an electrical power source.

The blower unit comprises an air inlet for drawing air into the blower unit and an air outlet for exhausting air to the air discharge unit, the air discharge unit being connected to the air outlet of the blower unit. Thus, the blower unit is arranged to generate an air flow for the air discharge unit comprising the discharge tube and the branching unit. In other words, the blower unit generates air flow to the first output tube and the second output tube. The blower unit comprises a power source and an impeller, said power source is arranged to drive the impeller for generating the air flow.

The portable leaf blower may also comprise an air flow regulator regulating the air flow ratio discharged through the first output tube and the second output tube. The air flow regulator is arranged in connection with the branching unit to regulate the air flow coming from the discharge tube to the first and second output tubes. The air flow regulators can for example divide the air flow into different air flow volumes and rates in different output tubes. An example of the air flows coming out from the output tubes can be a total of 7-10 m ³ /minute, or 8-9 m ³ /minute.

The branching unit comprising the first output tube having the first outlet opening, and the second output tube having the second outlet opening is arranged such that the first outlet opening, and the second outlet opening are preferably of the same size, in which case the air flow coming through them is the same unless it is separately adjusted to a different size, for example with throttles or like. This means that the diameter of the first outlet opening, and the second outlet opening is the same. The first outlet opening, and the second outlet opening are at a distance from each other because the first output tube and the second output tube are separate output tubes that connect only through the discharge tube or the branching adapter. The first outlet opening, and the second outlet opening are preferable at the same distance from the proximal end of the discharge tube.

An advantage of the invention is that a portable leaf blower having a first output tube and a second output tube in a branching unit extending from a single discharge tube connected to the blower unit allows the user to operate the portable leaf blower with only one hand and still effectively extend its controlled operation in moving leaves or the like even in areas where leaf control and movement is difficult, for example at the corners of the areas to be cleaned or near walls.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is described in detail by means of specific embodiments with reference to the enclosed drawings, in which

Figure 1 shows a schematic front view of a user with a portable leaf blower according to one embodiment of the invention;

Figure 2 shows a schematic side view of a user with a portable leaf blower according to one embodiment of the invention; and

Figure 3 shows a schematic top view of the portable leaf blower according to an embodiment of the invention;

Figure 4 shows another schematic top view of the portable leaf blower according to an embodiment of the invention;

Figures 5 to 7 shows different embodiments of the branching unit of the portable leaf blower according to invention.

DETAILED DESCRIPTION OF THE INVENTION

Figure 1 shows a schematic front view of a user with a portable leaf blower 1 according to one embodiment of the invention. The user preferably carries the portable leaf blower 1 on the back in such a way that the blower unit 2 is placed against the user's back and is supported, for example, by carrying straps 40 on the user's body like a backpack. The portable leaf blower 1 also comprises an air discharge unit 3 for discharging the air flow generated in the blower unit 2 out of the portable leaf blower 1. The air discharge unit 3 comprises a discharge tube 4 and a branching unit 5. The discharge tube 4 extends from the blower unit 2 and has a distal end 4a connected to the blower unit 2 and a proximal end 4b connected to the branching unit 5 such that there is a flow communication between the blower unit 2 and the discharge tube 4 and between the discharge tube 4 and the branching unit 5. The branching unit 5 comprises a first output tube 6 having a first outlet opening 16, and a second output tube 7 having a second outlet opening 17. The first output tube 6 and the second output tube 7 are placed in the branching unit 5 such a way that the air flows coming from the outlet openings 16, 17 can be directed to turn towards each other at a distance from the outlet openings. In other words, the output tubes 6, 7 are arranged to extend side by side in the branching unit 5 at a distance from each other so that they can be directed to the same point or to points near each other. In other words, so that the air flows exiting the first and second output tubes 6, 7 can be directed to the same point or to points near each other. This way the portable leaf blower 1 can be used one-handed but there will be two exiting air flows that can be directed to the same target for controlling to target, such as leaves, to move precisely to a desired location.

Figure 2 shows a schematic side view of a user having a portable leaf blower 1 on his back according to an embodiment of the invention. The portable leaf blower 1 is supported by the user by the carrying straps 40 by means of which the portable leaf blower 1 is supported in the user’s body so that user’s hand is used freely to guide the air discharge unit 3. The discharge tube 4 or the branching unit 5 preferably comprise a handle 50 by means of which the air flow coming out of the branching unit 5 is controlled and thus the portable leaf blower 1 is operated one handed. The handle 50 preferably comprises a power actuator for controlling the operation of a blower unit 2 for operating the portable leaf blower and controlling the air flow output.

Figure 3 shows a schematic top view of the portable leaf blower 1 according to an embodiment of the invention in which the portable leaf blower 1 comprises a blower unit 2 and an air discharge unit 3. The blower unit 2 generates an air flow and the air discharge unit 3 propels the air flow out of the portable leaf blower 1. The blower unit 2 comprises a power source 60 and an impeller 70. The blower unit 2 also comprises an air inlet for drawing air into the blower unit 2 and an air outlet for exhausting air to the air discharge unit 3 which is connected to the air outlet of the blower unit 2. The air inlet and the air outlet of the blower unit 2 are not shown in the figures. The blower unit 2 generates the air flow with the impeller 70 driven by the power source 60. The air discharge unit 3 connected to the blower unit 2 comprises a discharge tube 4 and a branching unit 5 comprising a first output tube 6 and a second output tube 7. The branching unit 5 is connected to the distal end 4b of the discharge tube 4 such that the flow communication between the discharge tube 4 and the branching tube 5 exists. The branching unit 5 comprises the first output tube 6 and the second output tube 7 having the flow communication to the discharge tube 4 such that the air flow exhausted from the blower unit 2 to the air discharge tube 4 is divided for the first output tube 6 and the second output tube 7 not until in the branching unit 5 such that the first output tube 6 is arranged to provide a first output air flow through the first outlet opening 16 and the second output tube 7 is arranged to provide a second output air flow through the second outlet opening 17. As the figure 3 shows the handle 50 is provided in connection with the discharge tube 4 in this embodiment but it may also be in connection with the branching unit 5.

Figure 4 shows another embodiment of the portable leaf blower 1 according to the invention in which the main difference for the embodiment shown in figure 3 is that the first output tube 6 of the branching unit 5 comprises a surface structure 10 in connection with an inner surface of the first output tube 6 and a surface structure 10 in connection with an inner surface of the second output tube 7. The surface structure 10 is inside the output tubes 6, 7 although the figure 4 shows other features as seen from outside. The surface structure 10 is arranged to the inner surface of the output tube 6, 7 for changing the movement of the air flow coming from the discharge tube 4 to the output tube 6, 7 before discharging from the outlet opening 16, 17. The surface structure is preferably a vortex groove structure but it may also be formed as ridges in the inner surface of the output tube thereby providing grooves in which the air flow flows and generates vortices.

Figure 5 shows an embodiment of the branching unit 5 of the portable leaf blower 1. The portable leaf blower 1 can be the one shown in figures 1-4 or alternatively a portable leaf blower 1 which is carried by hands of the user, or another kind of portable leaf blower 1 which is carried by the user. This means that the portable leaf blower 1 can be carried as a backpack, as a portable device carried in front of the user, as a handheld device, or any other kind of portable device. The branching unit 5 is connected to the distal end 4b of the discharge tube 4. The branching unit 5 comprises a common inlet opening 18 for the first output tube 6 and the second output tube 7 which means that the air flow coming through the discharge tube 4 enters the branching unit 5 through one inlet opening and the air flow is divided into two air flows in the branching unit 5 such that part of the air flow is discharged through the first output tube 6 and out from the first outlet opening 16, and part of the air flow is discharged through the second output tube

7 and out from the second outlet opening 17. The common inlet 18 is formed by a branch adapter 8 which in this embodiment of the invention is an integral part of the first output tube 6 and the second output tube 7 so that the branch adapter 8 forms the branching unit 5 together with the first output tube 6 and the second output tube 7. The branching unit 5 also comprises in this embodiment of the invention an adjustment element 9 provided in connection with the first output tube 6 and the second output tube 7. The adjustment element 9 is arranged to change the orientation of at least part of the output tube 6, 7 such that the outlet opening 16, 17 can be directed to supply the air flow to a desired target. In this embodiment shown in figure 5 only part of the output tube 6, 7 is adjustable.

Figure 6 shows another embodiment of the branching unit 5 of the portable leaf blower 1. The portable leaf blower 1 can be the one shown in figures 1-4 or alternatively a portable leaf blower 1 which is carried by hands of the user, or another kind of portable leaf blower 1 which is carried by the user. This means that the portable leaf blower 1 can be carried as a backpack, as a portable device carried in front of the user, as a handheld device, or any other kind of portable device. In this embodiment the branching unit 5 comprises a branch adapter 8 which is not integral with the first and second output tubes 6, 7. The branch adapter

8 is arranged between the discharge tube 4 and the first and second output tubes 6, 7 such that the branch adapter 8 forms a common inlet opening 18 for the first output tube 6 and the second output tube 7 for the air flow to flow from the discharge tube 4 to the branching unit 5 and separate outlet openings from the branch adapter 8 to the output tubes 6, 7 such that the branch adapter 8 has a first connecting outlet opening 28 to the first output tube 6 having a first inlet opening 26 so that the outlet opening 28 of the branch adapter 8 and the inlet opening 26 of the first output tube 6 provide a flow communication between the branch adapter 8 and the first output tube 6. Similarly, the branch adapter 8 has a second connecting outlet opening 38 to the second output tube 7 having a second inlet opening 27 so that the outlet opening 38 of the branch adapter 8 and the inlet opening 27 of the second output tube 7 provide a flow communication between the branch adapter 8 and the second output tube 7. In the embodiment shown in figure 6 the adjustment element 9 is arranged to only one output tube, which is the first output tube 6 in figure 6, and the other output tube, which is the second output tube 7 in figure 6, is a fixed meaning that the orientation of the output tube is not changeable. However, the output tubes 6, 7 can be removable from the branch adapter 8 and their positions can be changed in connection with the branch adapter 8.

Figure 7 shows still another embodiment of the branching unit 5 of the portable leaf blower 1. The portable leaf blower 1 can be the one shown in figures 1-4 or alternatively a portable leaf blower 1 which is carried by hands of the user, or another kind of portable leaf blower 1 which is carried by the user. This means that the portable leaf blower 1 can be carried as a backpack, as a portable device carried in front of the user, as a handheld device, or any other kind of portable device. The branching unit 5 of the embodiment shown in figure 7 comprises the first output tube 6 and the second output tube 7 only. In other words, the branching unit 5 consists of only the first output tube 6 and the second output tube 7. The first output tube 6 comprises a first inlet opening 26 for the air flow to flow from the discharge tube 4 into the first output tube 6, and the second output tube 7 comprises a second inlet opening 27 for the air flow to flow from the discharge tube 4 into the second output tube 7. In other words, the branching unit 5 consisting of the first output tube 6 and the second output tube 7 is connected to the discharge tube 4 such that the air flow is arranged to flow directly from the discharge tube 4 through the first inlet opening 26 to the first output tube 6 and through the second inlet opening 27 to the second output tube 7. Then the air flow flows through the first output tube 6 and the second output tube 7 and is discharged out of the portable leaf blower through the first outlet opening 16 and the second outlet opening 17. The branching unit 5 comprises an adjustment element 9 in connection with the distal ends of the first and second output tube 6, 7, the distal end of the first and second output tube 6, 7 being the end connected to the discharge tube 4. This means that the hole first and second output tubes 6, 7 are adjustable in their orientation relative to the discharge tube 4 and relative to each other.

The invention has been described above with reference to the examples shown in the figures. However, the invention is in no way restricted to the above examples but may vary within the scope of the claims.