CN215545394U

CN215545394U - Cutting tool

Info

Publication number: CN215545394U
Application number: CN202120387637.6U
Authority: CN
Inventors: 朱伯元; 刘瑞峰
Original assignee: Positec Power Tools Suzhou Co Ltd
Current assignee: Positec Power Tools Suzhou Co Ltd
Priority date: 2021-02-22
Filing date: 2021-02-22
Publication date: 2022-01-18
Anticipated expiration: 2031-02-22

Abstract

The utility model relates to a cutting tool, in particular an electric circular saw, comprising: a housing; a motor disposed within the housing and having an output shaft; the working shaft is arranged in the shell through a bearing; a saw blade mounted on the working shaft; a transmission assembly disposed between the output shaft and the working shaft to transmit a rotational force of the motor to the saw blade, the transmission assembly including a first gear mounted on the output shaft and a second gear mounted on the working shaft; wherein, the external diameter scope of saw bit does: 140 +/-5 mm, and the outer diameter range of the second gear is as follows: 29 ± 2mm, or, the maximum cutting depth range of the cutting tool is: 50 +/-2 mm, and the weight of the cutting tool is as follows: 2.4 + -0.2 kg. By setting the value ranges of the saw blade and the second gear or setting the maximum cutting depth range of the cutting tool and the weight of the cutting tool, the weight of the whole cutting tool can be reduced and the service life of parts can be prolonged as much as possible on the premise that the cutting tool meets the requirement of large cutting depth.

Description

Cutting tool

Technical Field

The utility model relates to a cutting tool, in particular to an electric circular saw.

Background

The cutting tool is a tool which takes a single-phase series motor as power and drives a circular saw blade to carry out sawing operation, and has the characteristics of safety, reliability, high working efficiency and the like. The cutting tool mainly comprises a motor, a reduction gearbox, a shield assembly, a bottom plate, an electric control system and the like. The cutting tool is typically powered by two means, one by a cable and the other by a battery pack. However, in the prior art, if a light-weight handheld cutting tool is used, the cutting depth is usually not enough, for example, a workpiece with a thickness of 50 can not be cut, and if a cutting tool with a large cutting depth is used, the cutting tool is too heavy, a user is tired when holding the cutting tool for a long time, and the controllability is poor. Therefore, the cutting tools on the existing market cannot meet the requirements of large cutting depth and light weight at the same time.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a cutting tool which can realize large cutting depth and is light in weight.

In order to achieve the purpose, the utility model provides the following technical scheme: a cutting tool, comprising:

a base plate;

the shell is movably connected with the bottom plate;

a motor disposed within the housing and having an output shaft;

the working shaft is used for mounting a saw blade and is arranged in the shell through a bearing;

a transmission assembly disposed between the output shaft and the working shaft to transmit a rotational force of the motor to a saw blade, the transmission assembly including a first gear mounted on the output shaft and a second gear mounted on the working shaft; wherein, the external diameter scope of saw bit is: 140 +/-5 mm, and the outer diameter range of the second gear is as follows: 29 + -2 mm.

Further, the maximum cutting depth range of the cutting tool is as follows: 50 ± 2mm, the weight of the cutting tool being: 2.4 + -0.2 kg.

Further, the cutting tool also includes a battery pack mounted on the housing.

Further, a projection of a center of gravity of the cutting tool is located within the base plate.

Further, the motor is a brushless motor.

Further, the working shaft is arranged in parallel with the output shaft, and the first gear is externally meshed with the second gear; in the height direction of the cutting tool, the working shaft is positioned below the output shaft.

Furthermore, the transmission assembly further comprises a reduction gearbox shell used for containing the first gear and the second gear, and the reduction gearbox shell is made of magnesium alloy or plastic.

Further, the casing includes the host computer casing that is used for accomodating motor, transmission assembly and certainly the casing of holding that host computer casing backward extends the formation, the guard shield subassembly is located the left side of host computer casing.

Furthermore, the shell is provided with a holding part for an operator to hold, and a holding position for a middle finger of the operator in the holding part is positioned outside the bottom plate.

In order to achieve the purpose, the utility model also provides the following technical scheme: a cutting tool, comprising:

a base plate;

the shell is movably connected with the bottom plate;

a motor disposed in the housing and having an output shaft outputting a rotational force to a saw blade to operate the saw blade;

the maximum cutting depth range of the cutting tool is as follows: 50 ± 2mm, the weight of the cutting tool being: 2.4 + -0.2 kg.

The utility model has the beneficial effects that: by setting the value ranges of the saw blade and the second gear or setting the maximum cutting depth range of the cutting tool and the weight of the cutting tool, the weight of the whole cutting tool can be reduced and the service life of parts can be prolonged as much as possible on the premise that the cutting tool meets the requirement of large cutting depth.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical solutions of the present invention more clearly understood and to implement them in accordance with the contents of the description, the following detailed description is given with reference to the preferred embodiments of the present invention and the accompanying drawings.

Drawings

FIG. 1 is a schematic view of a cutting tool according to an embodiment of the present disclosure;

FIG. 2 is a top view of the cutting tool shown in FIG. 1;

FIG. 3 is a cross-sectional view of the cutting tool of FIG. 1 in another orientation;

fig. 4 is a schematic structural view of the cutting tool shown in fig. 1 after the movable shield is folded.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art. In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Referring to fig. 1 to 3, a cutting tool 100 according to a preferred embodiment of the present invention is an electric circular saw. The cutting tool 100 includes a housing 1, a motor 2 disposed in the housing 1, a working shaft 3 for mounting a saw blade 200, the saw blade 200 mounted on the working shaft 3, a transmission assembly 4 for transmitting a rotational force of the motor 2 to the saw blade 200 to drive the saw blade 200 to rotate, a base plate 5 located below the housing 1 and movably connected to the housing 1, a guard assembly 6 for accommodating the saw blade 200, and an electric control assembly for controlling the operation of the motor 2.

It should be noted that, in fig. 1, a direction perpendicular to the plane of the bottom plate 5 is a height direction of the cutting tool 100 (a direction indicated by arrows a1-a 2), a cutting direction of the cutting tool 100 is a longitudinal direction of the cutting tool 100 (a direction indicated by arrows b1-b 2), in fig. 2, directions indicated by arrows c1-c2 are width directions perpendicular to the height direction and the longitudinal direction, and it should be noted that, when the cutting tool 100 is operated, the cutting tool 100 is usually held by a right hand, an operator usually stands on a left rear side of the cutting tool 100, a direction indicated by an arrow c1 in fig. 2 is a left side direction of the cutting tool 100, a direction indicated by an arrow c2 is a right side direction of the cutting tool 100, a direction indicated by an arrow b1 is a rear side direction of the cutting tool 100, and a direction indicated by an arrow b2 is a front side direction of the cutting tool 100.

The housing 1 includes a main housing 11 located above the bottom plate 5 and a holding housing 12 formed by extending backward from the main housing 11, wherein the holding housing 12 is substantially in a straight shape. The front end of the main machine shell 11 is rotatably connected with the bottom plate 5. The grip case 12 has a grip portion (not numbered) for an operator to grip, and a grip position (position indicated by an arrow e in fig. 1) in the grip portion for the operator to grip is located outside the bottom plate 5. The electric control assembly comprises a switch button 8 arranged at the bottom of the holding shell 12, the switch button 8 is used for starting the motor 2 to operate, and the switch button 8 is partially positioned in the bottom plate 1 or is completely positioned in the bottom plate 1. A holding position for the middle finger of the operator to hold is located on the rear side of the switch knob 8. The motor 2 and the transmission assembly 4 are housed in a main body case 11. In this embodiment, the main housing 11 includes a motor housing 111 for accommodating the motor 2 and a reduction gear housing 112 for accommodating the transmission assembly 4, the grip housing 12 is formed to extend rearward from the reduction gear housing 112, and the motor housing 111 is fixed to the reduction gear housing 112. The motor 2 is a brushless motor 2, and the motor 2 has an output shaft 21, and the axis Y direction of the output shaft 21 is the same as the width direction c1-c2 of the cutting tool 100. In order to reduce the overall weight, in this embodiment, the reduction gearbox housing 112 is made of magnesium alloy or plastic. In this embodiment, the transmission assembly 4 is a one-stage reduction transmission, but in other embodiments, the transmission assembly 4 may also be a multi-stage (two or more stages) reduction transmission or a more complex transmission mode, which will not be described in detail herein. The transmission assembly 4 comprises a first gear (not numbered) and a second gear 42 for realizing a one-stage reduction transmission, wherein the first gear is a large gear, the second gear 42 is a small gear, the first gear is mounted on the output shaft 21, and the second gear 42 is mounted on the working shaft 3. The first and second gears 42 are in external mesh. In this embodiment, the working shaft 3 is disposed parallel to the output shaft 21, and the working shaft 3 is located below the output shaft 21 in the height direction of the cutting tool 100.

The saw blade 200 is a circular saw blade 200, and the outer diameter D1 of the saw blade 200 has a value range of: 140 ± 5mm, the outer diameter D2 of the second gear 42 has a value range of: 29 + -2 mm. Therefore, the weight of the whole machine can be reduced as much as possible on the premise that the cutting tool 100 meets the requirement of large cutting depth. Specifically, the reason for adopting the value range is as follows: in order to make the cutting tool light, the overall dimension of the whole machine needs to be controlled, however, if the outer diameter of the saw blade 200 is too large, the whole machine is large and heavy, and if the outer diameter of the second gear 42 is large, the cutting depth is small, and if the outer diameter of the second gear 42 is too small, the service life of the second gear 42 is reduced, and by the above values, the relation of the cutting depth, the weight and the service life can be reasonably considered. In this embodiment, the cutting depth is the greatest and the useful life is the longest in the case of a comparable weight, and the cutting tool 100 is the lightest in weight in the case of a comparable cutting depth.

In addition, in order to meet the user's requirements to the maximum extent, in the case of meeting the cutting depth, considering lightness and lightness, making the user comfortable to handle, and reducing the working conformity, the maximum cutting depth H1 range of the cutting tool 100 is: 50 ± 2mm, the weight of the cutting tool 100 is: 2.4 + -0.2 kg. The weight of the cutting tool 100 includes the saw blade 200 and the battery pack 6.

In the above, the cutting tool 100 comprises a battery pack 6, which is powered by the battery pack 6, i.e. the cutting tool 100 further comprises a battery pack 6 for supplying electrical energy to the motor. The battery pack 6 is a detachable member. The battery pack 6 is detachably mounted at the rear of the grip housing 12, and the connection manner (including electrical connection and mechanical connection) between the battery pack 6 and the grip housing 12 is a common connection means in the prior art, so that the detailed description thereof is omitted. In this embodiment, the voltage of the battery pack 6 is 20V. Of course, in other embodiments, the cutting tool 100 may be powered by other means, such as by providing a cable plug on the cutting tool 100 to connect to the utility power, or by an adapter. When the cutting tool 100 is not provided with the battery pack 6, its weight consists of the weight of the housing 1, the weight of the motor 2 of the saw blade 200 and the weight of the transmission assembly 4 (the weight of the control assembly is negligible).

The shield assembly 6 is used to shield the saw blade 200 for safety and to prevent swarf from splashing. The shield assembly 6 may be of conventional design in the art and includes a stationary shield 61 and a movable shield 62, wherein the stationary shield 61 is located on the left or right side of the gearbox housing 112, and in this embodiment the stationary shield 61 is located on the left side of the gearbox housing 112 for improved visibility and for ease of control of the cutting process. The fixed shield 61 is fixedly installed on the gearbox shell 112, the movable shield 62 is sleeved in the fixed shield 61, the fixed shield 61 and the movable shield 62 are both arc-shaped structures, and the movable shield 62 can rotate in the fixed shield 61 to be folded into the fixed shield 61. The working shaft 3 is fixed in the speed reducing box shell 112 through the bearing 31, the second gear 42 is installed at one end of the working shaft 3, the other end of the working shaft extends into the fixed protective cover 61, the saw blade 200 is detachably connected with the working shaft 3, in actual work, different types of saw blades 200 can be adopted according to the material of a cut object, the saw blade 200 is arranged in the fixed protective cover 61, the fixed protective cover 61 covers part of the saw blade 200, and the movable protective cover 62 rotates in the fixed protective cover 61 to shield or leak part of the saw blade 200. An opening member (not shown) is provided between the movable guard 62 and the fixed guard 61, and when the electric circular saw is used, an operator manually pushes the opening member to rotate the movable guard 62 to expose a part of saw teeth (not shown) of the saw blade 200. The bottom plate 5 is connected with a fixed shield 61, and a connecting seat 51 is provided on a front side of the bottom plate 5, and the connecting seat 51 is connected with the fixed shield 61 by a pin (not numbered) so that the fixed shield 61 can rotate relative to the bottom plate 5. In the actual cutting, the fixed shield 61 changes from the relative position to the bottom plate 5 according to the cutting depth, and the rotation of the fixed shield 61 is to rotate the holding shell 12 relative to the bottom plate 5 by applying a force on the holding shell 12, so as to drive the fixed shield 61 to rotate relative to the bottom plate 5. The shield assembly 6 is made of a plastic material to further reduce the overall weight of the cutting tool 100.

In order to improve the accuracy of the cutting depth, the cutting tool 100 further includes a depth-adjusting bracket assembly 7, the depth-adjusting bracket assembly 7 is disposed on two sides of the main housing 11 opposite to the shield assembly 6, and in this embodiment, the depth-adjusting bracket assembly 7 is located on the right side of the main housing 11. The depth-adjusting bracket assembly 7 includes a bracket body 71 located at the right side of the main machine housing 11 and a locking device 72 provided on the bracket body 71. The bracket body 71 guides the main machine housing 11 to move in the direction of the cutting depth with respect to the base plate 5 about the first rotation axis X. In detail, an arc-shaped hole 711 defining that the main housing 11 rotates around the first rotation axis X is formed in the bracket body 71, and specifically, the arc-shaped hole 711 extends in a circumferential direction of the motor 2, and the arc-shaped hole 711 penetrates through the bracket body 71 in a direction parallel to the first rotation axis X. The first axis of rotation X is perpendicular to the cutting direction of the cutting tool 100 and parallel to the axis Y of the motor 2. The locking device 72 penetrates into the arc hole 711 and abuts against the end surface of the host housing 11 and is fixed with the bracket body 71 to lock the host housing 11 on the bottom plate 5. The bracket body 71 is an arc-shaped bent body 71 extending in the circumferential direction of the end surface of the main machine housing 11 and located in the circumferential direction of the main machine housing 11. The curved body 71 has a first end 712 and a second end 713 oppositely arranged, the first end 712 is a free end, the second end 713 is fixed on the bottom plate 5 through a fastener (not numbered), and the second end 713 is fixed on the bottom plate 5 through a fastener 714, so that the curved body 71 and the bottom plate 5 can be adjusted. The curved body 71 may be provided with a scale (not shown).

The base plate 5 is effective to support the cutting tool 100 during cutting, and the projection of the center of gravity of the cutting tool 100 is located within the base plate 5. In operation, as shown in fig. 4, the bottom plate 5 is placed on the working surface B-B, and the movable shield (not shown) of the shield assembly 6 does not shield the portion of the saw blade 200 below the base 5, so as to cut the object to be cut below the base 5, wherein the position of the saw blade 200 in fig. 4 is the maximum cutting depth position. In fig. 1, since the movable guard 62 shields the saw blade 200 under the base 5, the movable guard 62 extends beyond the bottom plate 5 (i.e. the movable guard 62 extends beyond the working surface), and the movable guard 62 interferes with the working surface (not numbered), at this time, the cutting tool 100 does not work and cannot be horizontally placed on the working surface. In the present invention, the base plate 5 is a rectangular base plate 5, the length direction of which is the cutting advancing direction of the cutting tool 100, and the width direction of which is perpendicular to the cutting advancing direction of the cutting tool 100. The bottom plate 5 is formed with a blade notch (not shown) through which the blade 200 passes, and the blade 200 passes through the blade notch and abuts against an object to be cut during cutting. Of course, in other embodiments, the bottom plate 5 may have other shapes, for example, the bottom plate 5 is a circular bottom plate 5, and the outer side of the circular bottom plate 5 is an outer circular side. The cutting tool 100 is designed to fall on the bottom plate 5 by projecting the gravity center of the cutting tool 100 in a direction perpendicular to the plane of the bottom plate 5, so that the gravity center of the cutting tool 100 is arranged forward, and therefore the cutting tool 100 can be effectively supported by the bottom plate 5 when the cutting tool 100 is horizontally placed on the working surface B through the bottom plate 5; the problem that the cutting tool 100 topples over does not occur, and the user experience is improved.

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above examples only show some embodiments of the present invention, and the description thereof is more specific and detailed, but not to be construed as limiting the scope of the utility model. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A cutting tool, comprising:

a base plate;

the shell is movably connected with the bottom plate;

a motor disposed within the housing and having an output shaft;

a transmission assembly disposed between the output shaft and the working shaft to transmit a rotational force of the motor to a saw blade, the transmission assembly including a first gear mounted on the output shaft and a second gear mounted on the working shaft; the saw blade is characterized in that the outer diameter range of the saw blade is as follows: 140 +/-5 mm, and the outer diameter range of the second gear is as follows: 29 + -2 mm.

2. The cutting tool of claim 1, wherein the maximum cutting depth range of the cutting tool is: 50 ± 2mm, the weight of the cutting tool being: 2.4 + -0.2 kg.

3. The cutting tool of claim 2, further comprising a battery pack mounted on the housing.

4. A cutting tool according to claim 2 or 3, wherein a projection of the centre of gravity of the cutting tool is located within the sole plate.

5. The cutting tool of claim 1, wherein the motor is a brushless motor.

6. The cutting tool of claim 1, wherein the working shaft is disposed parallel to the output shaft, and the first gear is externally engaged with the second gear; in the height direction of the cutting tool, the working shaft is positioned below the output shaft.

7. The cutting tool of claim 1, wherein the housing comprises a gearbox housing for receiving the transmission assembly, the gearbox housing being formed of a magnesium alloy or a plastic material.

8. The cutting tool of claim 7, wherein the housing includes a main housing for receiving the motor and transmission assembly and a grip housing extending rearwardly from the main housing, the cutting tool further comprising a shroud assembly located to the left of the main housing.

9. The cutting tool according to claim 1 or 8, wherein the housing has a grip portion for an operator to grip, and a grip position in the grip portion for a middle finger of the operator is located outside the base plate.

10. A cutting tool, comprising:

a base plate;

the shell is movably connected with the bottom plate;

the cutting tool is characterized in that the maximum cutting depth range of the cutting tool is as follows: 50 ± 2mm, the weight of the cutting tool being: 2.4 + -0.2 kg.