CN214721118U

CN214721118U - Chain saw

Info

Publication number: CN214721118U
Application number: CN202120008909.7U
Authority: CN
Inventors: 林国勋; 王加达
Original assignee: Techtronic Cordless GP
Current assignee: Techtronic Cordless GP
Priority date: 2021-01-05
Filing date: 2021-01-05
Publication date: 2021-11-16
Anticipated expiration: 2031-01-05
Also published as: EP4032672A2; EP4032672A3; AU2021290366A1

Abstract

A chain saw includes a housing, a drive unit accommodated in the housing, and a chain driven by the drive unit, the chain being disposed on a guide plate extending outward from the housing along a first axis, the drive unit being rotatable about a second axis. The second axis is located in or parallel to the plane of the guide plate. The chainsaw includes a front handle and a rear handle, the front handle having one end connected to the housing and another end including a free end. The drive unit includes a motor located between the front handle and the rear handle, at least a portion of the motor being located at the same height as the front handle. A battery mounting portion is formed on a side surface of the housing, and the motor and the battery mounting portion are substantially overlapped in a direction of the first axis.

Description

Chain saw

Technical Field

The present invention relates to a power tool, and in particular, to an electric chain saw and an arrangement of its main components.

Background

Chain saws are one of the most commonly used power tools. The electric chain saw uses electricity as a power source to drive a motor to work, and the motor drives a chain with a cutting edge to circularly move at a high speed so as to realize cutting. With the development of rechargeable battery technology, cordless electric chain saws using a battery pack as a power source appear in the market. In order to meet the long-term use demands of users, more and more electric chain saws employ large-capacity batteries.

However, the motor, the chain, and other parts of the electric chain saw are generally heavy, and the large-capacity battery further increases the volume and weight of the electric chain saw, and holding the electric chain saw for a long time may cause user fatigue, reduce work efficiency, and may cause safety problems.

SUMMERY OF THE UTILITY MODEL

The utility model aims at the above-mentioned defect that exists among the prior art, design an electric chain saw that has compact structure and accords with ergonomic, improve user's use and experience.

To achieve this object, the present invention provides a chain saw comprising a housing, a drive unit accommodated in the housing and a chain driven by the drive unit, the chain being arranged on a guide plate extending outward from the housing along a first axis, the drive unit being rotatable about a second axis, the chain saw further comprising a front handle, one end of the front handle being connected to the housing, the other end comprising a free end.

Further, the second axis is located in or parallel to the plane of the guide plate, optionally at an angle to the first axis. The angle is 45 to 135 degrees, preferably 90 to 135 degrees, more preferably 90 to 110 degrees.

Further, the chain saw further comprises a rear handle, and the drive unit comprises a motor, which is located between the front handle and the rear handle. Preferably, at least a portion of the motor is located at the same height as the front handle.

Further, the housing includes an upper portion and a lower portion, the front handle extending from the upper portion, the guide plate extending from the lower portion, the rear handle connecting the upper portion and the lower portion, at least a portion of the motor being located within the upper portion.

Further, a side surface of the case forms a battery mounting portion. The motor and the battery mounting portion substantially overlap in the direction of the first axis.

Further, the rear handle extends along a third axis, the first axis is located on a first side of the third axis as viewed from above the chainsaw, and the front handle and the battery mount are located on a second side of the third axis, the first side being opposite to the second side.

Further, a distance between the outer surface of the battery mounting portion and the third axis is greater than a distance between the first axis and the third axis.

Further, the chainsaw further comprises a battery for powering the motor, the motor being located above the battery as viewed from the side of the chainsaw, preferably with the front end of the battery located below the front handle and the rear end of the battery located below a trigger provided on the rear handle, preferably with the downwardly extending section of the second axis intersecting the battery.

Further, the front handle defines a tool receiving space therein, the space being accessible from the free end of the front handle.

Further, the free end includes a tool holder for holding a tool, the tool holder being removably mounted at the free end, preferably one end of the tool holder forming a gripping portion for gripping a head of the tool, the tool holder defining a bore through which a shank of the tool passes into the front handle.

Further, the chainsaw further comprises a control unit for controlling the drive unit, the control unit comprising a circuit board mounted directly or indirectly to one end of the drive unit, preferably the circuit board is arranged coaxially with the drive unit.

Further, the housing forms at least one of an air inlet through which air enters the housing, cools the driving unit and the circuit board, and then is discharged through the air outlet.

Drawings

Fig. 1 is a perspective view of an electric chain saw according to an embodiment of the present invention.

Fig. 2 is another perspective view of an electric chain saw according to an embodiment of the present invention.

Fig. 3 is a side view of an electric chain saw according to an embodiment of the present invention.

Fig. 4 is a top view of an electric chain saw according to an embodiment of the present invention.

Fig. 5 is an exploded view of a front handle of a power chain saw according to one embodiment of the present invention.

Fig. 6 is another side view of an electric chain saw according to an embodiment of the present invention.

Detailed Description

The invention will be further explained with reference to the drawings and the specific embodiments. It should be noted that the terms "upper", "lower", "left", "right", "longitudinal", "transverse", "inner", "outer", "vertical", "horizontal", etc. used herein to indicate orientation or positional relationship are based only on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device/element referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention.

An electric chain saw 100 according to one embodiment of the present invention is shown in fig. 1 and 2 and includes a housing 10, a working assembly extending outwardly from the housing 10, a drive unit disposed within the housing for driving the working assembly, and a power supply device for supplying electrical power to the drive unit.

The working assembly of the electric chainsaw includes a chain 20 and a guide plate 21. The guide plate 21 has one end supported in the housing 10 and the other end extending out of the housing 10 along the first axis L1, and the chain 20 is fitted over the sprocket (not shown) and the guide plate 21 so as to be guided along the edge of the guide plate. The chain 20 is provided with a saw blade to perform cutting. To adjust the tension of the chain 20, the guide plate 21 is designed to be movable along the first axis L1 relative to the housing 10. For the electric chain saw shown in fig. 1-2, a user first unscrews the fixing nut 22 on the cover plate 24 using a wrench, and then rotates the screw 23 clockwise or counterclockwise using a screwdriver to move the guide plate 21 along the first axis L1, thereby tensioning or slackening the chain 20.

The electric chain saw has a rear handle 30 (main handle) and a front handle 31 (auxiliary handle). The user can hold the rear handle 30 and the front handle 31 with both hands while operating the electric chain saw, resulting in better stability when cutting an object. In the present embodiment, the housing 10 is assembled from left and right half shells and includes an upper portion 11 and a lower portion 12, wherein a front handle 31 is located at the upper portion 11 and extends sideward, a chain 20 and a guide plate 21 extend from the lower portion 12, and a rear handle 30 connects the upper portion 11 and the lower portion 12. The front handle 31 and/or the rear handle 30 may be separate components mounted to the housing or may be integrally formed on the housing.

Fig. 3 shows the side of the power chain saw with one side half shell removed to show the components within the housing. In the present embodiment, the driving unit includes a motor 50, which may be a dc brushless motor, a dc brushed motor, an ac motor, or the like. The motor 50 is controlled by a control unit which is capable of controlling activation or deactivation of the motor 50 in response to user operation of the trigger 61.

At least a portion of the motor 50 in the electric chain saw is located within the upper portion 11 of the housing 10. The motor 50 is shown in fig. 3 as being located between the front handle 31 and the rear handle 30. Preferably, at least a portion of the motor 50 is located at the same height as the front handle 31. This arrangement makes the most of the inner space of the housing 10, contributing to a reduction in the overall size of the electric chain saw. Also shown in fig. 3 is a motor holder 52 that surrounds at least a portion of the motor 50 and is supported by the housing 10 for fixing the position of the motor 50. Optionally, a vibration damping member is disposed between the motor 50 and the motor holder 52 or between the motor holder 52 and the housing 10 to prevent damage due to excessive vibration amplitude when the motor 50 rotates at a high speed.

The motor 50 drives the sprocket to rotate through the transmission assembly. In this embodiment, the transmission assembly includes a speed reduction mechanism and a transmission mechanism. The speed reducing mechanism is connected with an output shaft of the motor and used for reducing the rotating speed and improving the torque. The transmission mechanism is connected with the output end of the speed reducing mechanism and used for transmitting power to the chain wheel. The reduction mechanism may be at least one stage of the planetary gear set 51, or a gear set formed by meshing a plurality of gears of different sizes. The transmission mechanism may be a

bevel gear

53, 54 or a spur gear. It should be understood that the transmission assembly may include any mechanism capable of converting the rotational motion of the motor output shaft into the rotational motion of the sprocket.

The motor 50 rotates about a second axis L2, which in some embodiments is parallel to the first axis L1 as viewed from the side of the electric chain saw. In the embodiment shown in fig. 3, however, the second axis L2 is angled with respect to the first axis L1. Preferably, the angle is between 45 and 135 degrees, such as 60 degrees, 70 degrees, 80 degrees, 90 degrees, 100 degrees, 110 degrees, 120 degrees. More preferably, the angle is a right angle or an obtuse angle, i.e. 90 to 135 degrees. Further, if the angle is close to 90 degrees, for example, 90 degrees to 110 degrees, it means that the motor 50 is positioned substantially vertically within the housing, which allows the dimension of the housing upper portion 11 in the front-rear direction to be shortened. On the other hand, the second axis L2 is preferably located in the plane of the guide plate 21 or parallel to the plane of the guide plate 21. It should be understood that parallelism in the foregoing is not required to be exactly parallel, and the scope includes substantial parallelism.

The power supply device of the electric chain saw may be a battery 40 allowing multiple charging, which is mounted on a battery mounting portion 13 located on the side of the housing 10. The battery mounting portion 13 has a structure that fits the battery 40, including a cavity for receiving a battery insertion portion, a guide rail for guiding the battery to slide, and the like. In the embodiment shown in fig. 1, the battery mount section 13 is formed on the side of the lower section 12 of the case 10. The motor 50 located in the upper portion 11 of the housing 10 and the battery mount portion 13 located in the lower portion 12 of the housing 10 at least partially overlap, preferably substantially overlap, in the direction of the first axis L as viewed from the side.

The battery may be a universal battery pack that can be mounted to and power other types of power tools. In this embodiment, the battery is an 18V lithium ion battery pack. In other embodiments, the battery may have other nominal output voltages, such as 12V, 14V, 24V, 36V, 40V, etc. In an embodiment not shown, the chainsaw may also be a corded power tool that is connected to a power source by an electrical cord.

Fig. 4 is a plan view of the electric chain saw, in which the relative positions of the front handle 31, the rear handle 30, the battery 40, the chain 20, the guide plate 21, and the battery mount 13 are shown. For convenience of description, the central axis of the rear handle 30 is defined as a third axis L3. The first axis L1 is located on a first side of the third axis L3 and the front handle 31 is located on an opposite second side of the third axis L3 as viewed from above. Since the chain 20, the guide plate 21, and the drive train of the chainsaw are located on the first side of the third axis L3, the center of gravity of the entire chainsaw is biased to the first side of the third axis L3, which results in additional force being applied by the user to keep the chainsaw balanced while holding the chainsaw. For this reason, the battery mount section 13 is disposed on the second side of the third axis L3 in the present embodiment. Preferably, the distance d2 between the outer surface of the battery mount section 13 and the third axis L3 is greater than the distance d1 between the first axis L1 and the third axis L3. When the battery 40 is mounted, a distance d3 between the outer surface of the battery 40 and the third axis L3 is less than a distance d4 between the outermost end of the front handle 31 and the third axis L3. Thus, after the battery is installed, the center of gravity of the entire chain saw will be located near the third axis L3, making it easier and less labor intensive for the user to control the chain saw. Even if a large-capacity battery pack is mounted, the user can feel the good balance of the chain saw.

Fig. 5 shows a front handle 31 which is generally cylindrical and has a first end 311 connected to the housing and an opposite second end 312. In this embodiment, the second end 312 is a free end that is not connected to the housing. It should be understood that the front handle may have other shapes, such as an L-shape, a U-shape, etc. The front handle 31 is configured to have a hollow space that can receive a tool 33. The user can remove the tool 33 from the front handle 31 when desired and replace the tool 33 in the front handle 31 after use. The tool may be removed through an opening formed in the outer surface of the front handle, or the front handle may be removed after being disassembled. In the embodiment shown in fig. 5, the second end 312 of the front handle 31 forms an opening through which a user can access and remove a tool in the space through the second end 312. The tool 33 may be a flat wrench having a head 331 and a shank 332 for loosening or tightening a nut, such as the retaining nut 22 on the cover plate 24 shown in fig. 2. In other embodiments, the tool may be a screwdriver, a security key, a locking key, etc., which may be used to perform some operation of the power chain saw, such as tensioning the chain, locking and unlocking, etc. In an embodiment not shown, two or more tools may be accommodated in the front handle. It is also envisaged that a single tool may perform two or more functions, for example the two ends of the tool acting as a wrench and screwdriver respectively.

Since the electric chain saw vibrates during operation, in order to prevent the tool 33 from falling out of the front handle 31, a tool holder 32 for holding the tool 33 may be provided in the front handle 31. The tool holder 32 shown in fig. 5 is mounted on the second end 312 of the front handle 31. One end of the tool holder 32 forms a gripping portion 321 for gripping a head 331 of the tool 33. A positioning member, such as a longitudinally extending rib 322, is formed on the outer wall of the tool holder 32, and cooperates with a rib 313 formed on the inner wall of the front handle 31 to position the tool holder 32 at a predetermined position in the front handle 31. It will be appreciated that other forms of securing member are possible, provided that they are capable of securely mounting the tool holder on the front handle. The tool holder 32 also defines a bore 323 for the shank 332 of the tool 33 to pass through the tool holder 32 into the hollow space of the front handle 31.

If the user wishes to replace a tool received in the front handle but the new tool is of a shape or size such that it cannot be secured to the tool holder 32, he may remove the current tool holder and then mount another tool holder suitable for securing the new tool to the second end 312 of the front handle 31. That is, the tool holder itself may also be replaced to accommodate different tools.

Turning to fig. 3, a control unit for the electric chain saw is shown. In this embodiment, the control unit is integrated into the drive unit. Specifically, the circuit board 60 of the control unit is disposed at one end of the motor 50 and is located within the upper portion 11 of the housing. It should be appreciated that the circuit board 60 may be mounted or connected to one end of the motor directly or indirectly by any means, such as by a fastener connection, snap fit, etc. Preferably, the circuit board 60 is shaped to correspond to the cross-sectional shape of the motor 50, such as substantially circular, and is disposed coaxially with the motor 50. In this way, no additional space needs to be reserved in the housing 10 to accommodate the circuit board, thereby further reducing the size of the housing. In an embodiment not shown, the control unit may be provided at a position close to the battery mounting portion 13 in the side of the motor 50, in the rear handle 30, or in the lower portion 12 of the housing.

In addition to the reduced size making the layout of the components within the housing more compact, another advantage of integrating the control unit into the drive unit is to increase the efficiency of heat dissipation, since the motor and the circuit board can be cooled together. An air inlet and an air outlet are formed on a shell of the electric chain saw, air enters the shell from the air inlet, flows through the motor to cool the shell and then is discharged from the air outlet. Since the circuit board is disposed at one end of the motor, the circuit board is also cooled by the cooling air flowing into or out of the motor. Preferably, at least one of the intake opening and the outtake opening is provided at an upper portion of the housing. To accelerate the air flow, a fan may be positioned within the housing adjacent the air inlet or outlet to urge air into or out of the housing. In addition, a radiator can be arranged between the circuit board and the motor to further improve the radiating efficiency.

In fig. 6, a side view of the electric chain saw with the battery 40 installed is shown, with an upper portion of the housing removed to show the motor 50. The motor 50 is located above the battery 40 as viewed from the side, and a downward extension of the rotational axis L2 of the motor 50 intersects the battery 40. In this embodiment, the front end 41 of the battery 40 is located below the front handle 31 and the rear end 42 is located below the trigger 61 on the rear handle 30. The arrangement is such that the vertical plane P1 in which the center of gravity G1 of the motor 50 lies is close to the vertical plane P2 in which the center of gravity G2 of the battery 40 lies, and both vertical planes P1, P2 are located between the front handle 31 and the rear handle 30.

To sum up, the utility model discloses the arrangement to the essential element in the electric chain saw improves, especially motor, battery, handle and control unit. In one aspect, an electric chain saw according to the present invention has a smaller volume housing than conventional designs. In another aspect. According to the utility model discloses an electric chain saw has optimized the weight distribution of essential element, makes the user can operate the chain saw more stably and laborsavingly, especially when both hands grip preceding, the back handle of chain saw simultaneously.

While the invention has been described in detail in connection with only a limited number of embodiments, it should be understood that the invention is not limited to such disclosed embodiments. Those skilled in the art can conceive of other embodiments, including variations, modifications, substitutions or equivalent arrangements of parts, which are within the spirit and scope of the invention.

Claims

1. A chainsaw comprising a housing, a drive unit accommodated in the housing, and a chain driven by the drive unit, the chain being arranged on a guide plate extending outwardly from the housing along a first axis, the drive unit being rotatable about a second axis, characterized in that the chainsaw further comprises a front handle, one end of which is connected to the housing and the other end of which comprises a free end.

2. A chainsaw as recited in claim 1 wherein said second axis is in or parallel to a plane in which said guide plate lies.

3. The chainsaw of claim 2, wherein the second axis is angled with respect to the first axis.

4. A chainsaw according to claim 3 wherein the angle is 45 to 135 degrees.

5. The chain saw of claim 4, wherein the angle is 90 degrees to 135 degrees.

6. The chain saw of claim 4, wherein the angle is 90 to 110 degrees.

7. The chainsaw of claim 1, further comprising a rear handle, wherein the drive unit comprises a motor positioned between the front and rear handles.

8. The chain saw of claim 7, wherein at least a portion of the motor is located at the same height as the front handle.

9. The chainsaw of claim 7, wherein the housing includes an upper portion from which the front handle extends and a lower portion from which the guide plate extends, the rear handle connects the upper and lower portions, and at least a portion of the motor is located within the upper portion.

10. A chainsaw as recited in any one of claims 7 to 9 wherein a side of said housing forms a battery mount.

11. The chainsaw of claim 10, wherein the motor and the battery mount overlap in the direction of the first axis.

12. The chainsaw of claim 10, wherein the rear handle extends along a third axis, the first axis being located on a first side of the third axis as viewed from above the chainsaw, and the front handle and the battery mount being located on a second side of the third axis, the first side being opposite the second side.

13. The chainsaw of claim 12, wherein a distance between an outer surface of the battery mount and the third axis is greater than a distance between the first axis and the third axis.

14. A chainsaw as recited in any one of claims 7 to 9 further comprising a battery for powering the motor, the motor being located above the battery when viewed from the side of the chainsaw.

15. The chainsaw of claim 14, wherein a front end of the battery is located below the front handle and a rear end of the battery is located below a trigger disposed on the rear handle.

16. The chain saw as recited in claim 14, wherein a downwardly extending segment of said second axis intersects said battery.

17. A chainsaw as recited in any one of claims 1 to 9 wherein said front handle defines a tool receiving space therein, said space being accessible from said free end of said front handle.

18. A chainsaw as set forth in claim 17 wherein said free end includes a tool holder for holding said tool, said tool holder being removably mounted to said free end.

19. The chain saw as recited in claim 18, wherein an end of said tool holder forms a clamping portion for clamping a head of said tool, said tool holder defining an aperture through which a shank of said tool passes into said front handle.

20. A chainsaw as recited in any one of claims 1 to 9 further comprising a control unit for controlling said drive unit, said control unit comprising a circuit board mounted directly or indirectly to one end of said drive unit.

21. The chain saw of claim 20, wherein the circuit board is disposed coaxially with the drive unit.

22. The chain saw of claim 20, wherein the housing defines at least one of an air intake vent through which air enters the housing, cools the drive unit and the circuit board, and is then discharged through the air outlet vent.