CN113909565A

CN113909565A - Electric circular saw

Info

Publication number: CN113909565A
Application number: CN202110990704.8A
Authority: CN
Inventors: 吹拔正敏; 王洪斌
Original assignee: Nanjing Chervon Industry Co Ltd
Current assignee: Nanjing Chervon Industry Co Ltd
Priority date: 2017-12-13
Filing date: 2018-12-13
Publication date: 2022-01-11
Also published as: CN113909564A; CN109909548B; CN209477418U; WO2019114777A1; CN109909548A

Abstract

The invention discloses an electric circular saw, comprising: the output shaft is used for mounting the saw blade; the motor is used for driving the output shaft to rotate; a housing including a handle symmetrically disposed about a first plane; wherein, the casing still includes: a first accommodating part formed with a first accommodating chamber for accommodating the motor, the first accommodating part including a first portion disposed on a left side of the first plane and a second portion disposed on a right side of the first plane; a coupling portion for coupling a power supply unit capable of supplying power to the electric circular saw; the handle has a first end and a second end respectively located at both ends in an extending direction thereof, the first accommodating portion is connected to the first end of the handle, and the coupling portion is connected to the second end of the handle. The electric circular saw has good balance performance.

Description

Electric circular saw

The application is a divisional application of patent application with application number 201811521769.2 (the application date of the original application is 12 months and 13 days in 2018, and the name of the invention is electric circular saw).

Technical Field

The invention relates to an electric tool, in particular to an electric circular saw.

Background

The electric circular saw generally includes a housing, a saw blade, a guard, a base plate, a motor, and a power supply device, wherein, in the existing electric circular saw, the motor is generally disposed at one side of the saw blade, which causes the center of gravity of the entire electric circular saw to be located at one side of the saw blade, and the distance between the center of gravity and the symmetry plane of the handle portion is relatively large, thereby resulting in that the balance performance of the electric circular saw is difficult to be improved.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention aims to provide an electric circular saw with good balance performance.

In order to achieve the above object, the present invention adopts the following technical solutions: an electric circular saw comprising: the output shaft is used for mounting the saw blade; the motor is used for driving the output shaft to rotate; a housing including a handle symmetrically disposed about a first plane; wherein, the casing still includes: a first accommodating part formed with a first accommodating chamber for accommodating the motor, the first accommodating part including a first portion disposed on a left side of the first plane and a second portion disposed on a right side of the first plane; a coupling portion for coupling a power supply unit capable of supplying power to the electric circular saw; the handle has a first end and a second end respectively located at both ends in an extending direction thereof, the first accommodating portion is connected to the first end of the handle, and the coupling portion is connected to the second end of the handle.

Further, the combining portion is connected with an electric energy input terminal for being connected with an electric energy output terminal on the battery pack.

Further, the output shaft is rotatable about a first axis when driven by the motor, the motor including a motor shaft rotatable about a second axis, the first axis of rotation of the output shaft and the second axis of rotation of the motor being parallel to one another.

Further, the distance between the first axis and the second axis is equal to or greater than 50mm and equal to or less than 120 mm.

Further, when the output shaft is provided with the saw blade, the saw blade extends in a cutting plane, and the cutting plane is perpendicular to the first axis; the motors are distributed on both sides of the cutting plane.

Further, the electric circular saw further includes: the transmission device is used for realizing power transmission between the motor and the output shaft; the casing still includes: a second accommodating part formed with a second accommodating chamber for accommodating the transmission; the handle connects the first accommodating part and the combining part at the upper side of the first accommodating part and the combining part; the second receiving portion connects the first receiving portion and the coupling portion at lower sides thereof.

Further, the electric circular saw further includes: a circuit board disposed in the second receiving portion; a fan disposed within the housing; wherein the housing is further formed with an airflow inlet and an airflow outlet; when the fan rotates, a heat dissipation airflow which flows into the shell from the airflow inlet and then flows out of the shell from the airflow outlet can be formed in the shell; the circuit board, the transmission device and the motor are all arranged on a circulation path of the heat dissipation airflow.

Further, the electric circular saw further includes: the transmission device is used for realizing power transmission between the motor and the output shaft; the casing still includes: a second accommodating part formed with a second accommodating chamber for accommodating the transmission; the handle, the first accommodating part, the second accommodating part and the combining part are sequentially connected and are surrounded with a through hole for a hand of a user to pass through so as to hold the handle.

Furthermore, the combining part is fixedly connected with a power line, and one end of the power line, which is far away from the combining part, is provided with a plug.

Further, the housing further includes: the protective cover assembly comprises a fixed protective cover and a movable protective cover which can rotate relative to the fixed protective cover; the first receiving portion is disposed at an upper side of the shroud assembly.

Further, the distance between the center of gravity of the electric circular saw and the first plane is not less than 0 and not more than 20 mm.

Further, the joining portion is disposed symmetrically with respect to the first plane.

Further, the output shaft can rotate around a first axis when driven by the motor, and the combining part and the first accommodating part are respectively arranged on two sides of a second plane which passes through the first axis and is perpendicular to the first plane.

Further, the housing further includes: the protective cover assembly comprises a fixed protective cover and a movable protective cover which can rotate relative to the fixed protective cover; a notch which is opened forwards so that the saw blade can contact the workpiece is formed between the movable shield and the fixed shield, the first accommodating part is arranged at the front end of the handle, and the combining part is arranged at the rear end of the handle.

The invention has the advantages that: through the structure of rational arrangement electric circular saw, especially optimize the spatial arrangement of structures such as motor, casing, handle for this electric circular saw's focus is close to the symmetry plane of handle portion, makes electric circular saw's balance performance good.

Drawings

Fig. 1 is a perspective view of an electric circular saw of a first embodiment of the present invention;

FIG. 2 is a perspective view of the electric circular saw of FIG. 1 from another angle;

FIG. 3 is a front view of the electric circular saw of FIG. 1;

FIG. 4 is a rear view of the electric circular saw of FIG. 1;

FIG. 5 is a top view of the electric circular saw of FIG. 1;

FIG. 6 is a cross-sectional view of the electric circular saw of FIG. 5 taken along line A-A;

FIG. 7 is a cross-sectional view of the electric circular saw of FIG. 5 taken along line B-B;

FIG. 8 is a front view of the electric circular saw of FIG. 3 with the battery pack removed;

FIG. 9 is a rear view of the electric circular saw of FIG. 4 with the rear housing portion removed;

FIG. 10 is a perspective view of the structure shown in FIG. 9;

FIG. 11 is a perspective view of another angle of the structure shown in FIG. 9;

fig. 12 is a perspective view of the structure shown in fig. 11 with the heat sink removed;

fig. 13 is an exploded view of the electric circular saw of fig. 1;

FIG. 14 is a perspective view of another angle of the structure shown in FIG. 13;

fig. 15 is a rear view of a housing portion of the electric circular saw of the second embodiment after removal;

fig. 16 is a perspective view of a housing portion of the electric circular saw of the third embodiment after removal;

fig. 17 is a rear view of a housing portion of the electric circular saw of the fourth embodiment after removal;

fig. 18 is a front view of the electric circular saw of the fifth embodiment;

fig. 19 is a front view of an electric circular saw of a sixth embodiment;

fig. 20 is a front view of an electric circular saw of a seventh embodiment;

fig. 21 is a front view of an electric circular saw of an eighth embodiment.

Detailed Description

The electric circular saw 100 of the first embodiment shown in fig. 1 may be used to cut wood, fiberboard, plastic, and the like. As shown in fig. 1 and 7, the electric circular saw 100 includes: the device comprises a shell 11, an output shaft 121, a saw blade 122, a bottom plate 13, a motor 14 and a power supply device 15. The housing 11 is configured to accommodate a motor 14 and the like, and the motor 14 is configured to provide a power source and can drive the output shaft 121 to rotate around the first axis 101 to output power. The saw blade 122 is used to cut a workpiece, and the base plate 13 is formed with a base plate plane 131 for contact with the workpiece. The power supply device 15 is used for supplying power to the motor 14, and the power supply device 15 may be a battery pack 151 or an alternating current power line.

For convenience of explanation of the technical solution of the present invention, upper, lower, front, rear, left and right sides as shown in fig. 1 are also defined.

As shown in fig. 2 to 7, the housing 11 includes: a handle 111, a first receiving portion 112, a coupling portion 113, and a second receiving portion 114. The handle 111 is used for holding by a user, and the handle 111 is also symmetrically arranged about a first plane 102, the first plane 102 being perpendicular to the first axis 101 of rotation of the output shaft 121. The handle 111 has a first end 111a and a second end 111b at both ends in the extending direction thereof, respectively. The handle 111 is further provided with a trigger switch 111c and a safety switch 111d, the trigger switch 111c and the handle 111 are movably connected, when a user holds the handle 111, the user's hand holding the handle 111 can trigger the trigger switch 111c to start the electric circular saw 100, the safety switch 111d is arranged on the handle 111 or near the handle 111, and the safety switch 111d is used for locking the trigger switch 111c at a position which is not triggered by the user, so that the electric circular saw 100 is prevented from being accidentally started, and the user is protected from being injured.

The first accommodating portion 112 is provided at a first end 111a in the extending direction of the handle 111, and the first accommodating portion 112 includes a first portion provided on the left side of the first plane 102 and a second portion provided on the right side of the first plane 102. The first accommodating portion 112 is also formed with a first accommodating chamber 112a, and the motor 14 is disposed in the first accommodating chamber 112 a. The shape of the outer surface of the first receiving portion 112 may be designed to be suitable for a user to hold, that is, the first receiving portion 112 may also be used as a secondary handle for the user to hold, so that when the user operates the electric circular saw 100, one hand of the user holds the handle 111 and the other hand holds the first receiving portion 112, so that the user can hold the electric circular saw 100 more stably, and meanwhile, because the first receiving portion 112 can be used for both receiving the motor 14 and holding by the user, the electric circular saw 100 does not need to separately and additionally provide a secondary handle for the user to hold, so that the manufacturing cost can be greatly saved, the size of the electric circular saw 100 is also reduced, and the weight of the electric circular saw 100 is reduced. The first receiving portions 112 are distributed on both sides of the first plane 102, thereby facilitating the center of gravity of the entire electric circular saw 100 to be disposed closer to the first plane 102 in a direction perpendicular to the first plane 102. For example, in the present embodiment, the distance between the center of gravity of the electric circular saw 100 and the first plane 102 is 0 to 10mm, and the distance between the center of gravity of the electric circular saw 100 and the first plane 102 is 0 to 5 mm. When the center of gravity of the entire electric circular saw 100 is set at a position close to the first plane 102, the user holds the electric circular saw 100 more stably, and the user operates the electric circular saw 100 with the overall machine more balanced and less vibration.

The coupling portion 113 is provided at the second end 111b in the extending direction of the handle 111, that is, the coupling portion 113 and the first accommodating portion 112 are provided at both ends in the extending direction of the handle 111, respectively. The coupling portion 113 is used to couple the power supply device 15 that supplies power to the electric circular saw 100. In the present embodiment, the power supply device 15 is specifically a battery pack 151. The coupling portion 113 is used to detachably couple a battery pack 151, and the battery pack 151 can supply power to the motor 14 when mounted to the coupling portion 113. The coupling portion 113 is connected with a power input terminal (not shown) for connection with a power output terminal on the battery pack 151. In the present embodiment, the coupling portion 113 is also symmetrically disposed about the first plane 102, and the battery pack 151 mounted to the coupling portion 113 is also symmetrically disposed about the first plane 102, so that it is further facilitated that the center of gravity of the whole electric circular saw 100 is disposed close to the first plane 102, and it is further facilitated that the user can operate the electric circular saw 100 more stably. The first receiving portion 112, the handle 111, and the coupling portion 113 are sequentially arranged in a direction of a first straight line 103 perpendicular to the first axis 101, and the handle 111 is located between the first receiving portion 112 and the coupling portion 113, or the first receiving portion 112 and the coupling portion 113 are located at both sides of the handle 111, so that it is advantageous to arrange the center of gravity of the entire electric circular saw 100 close to the handle 111 in a direction perpendicular to the first axis 101 and parallel to the first plane 102, thereby improving the balance performance of the electric circular saw 100. It should be noted that the first accommodating portion 112, the handle 111, and the coupling portion 113 are arranged in this order in the direction of the first straight line 103, and any one of them is not strictly limited to extend in the direction of the first straight line 103, as long as they appear substantially on one straight line as a whole, and it can be considered that the first accommodating portion 112, the handle 111, and the coupling portion 113 are arranged in this order in the direction of the first straight line 103. In the present embodiment, the output shaft 121 is rotatable about the first axis 101 when driven by the motor 14, and the coupling portion 113 and the first accommodating portion 112 are respectively disposed on both sides of a second plane 107 passing through the first axis 101 and perpendicular to the first plane 102. More specifically, the first receiving portion 112 is disposed on the left side of the handle 111, that is, the first receiving portion 112 is disposed on one side of the advancing direction of the electric circular saw 100, and the coupling portion 113 is disposed on the right side of the handle 111, that is, the coupling portion 113 is disposed on one side of the electric circular saw 100 close to the user.

As shown in fig. 4 and 9, the second receiving portion 114 is disposed at a rear side of the saw blade 122, and the second receiving portion 114 is formed with a second receiving cavity 114 a. The handle 111 connects the first receiving portion 112 and the coupling portion 113 in one direction, and the second receiving portion 114 connects the first receiving portion 112 and the coupling portion 113 in the other direction. The second receiving portion 114 is also provided at a lower side of the handle 111. Further, the handle 111 connects both the first receiving portion 112 and the coupling portion 113 at an upper side thereof, and the second receiving portion 114 connects both the first receiving portion 112 and the coupling portion 113 at a lower side thereof.

As shown in fig. 1, 13 and 14, the housing 11 may be further divided into a front housing part 115, a rear housing part 116 and a middle housing part 117, wherein the front housing part 115 is disposed at the front side of the middle housing part 117, the rear housing part 116 is disposed at the rear side of the middle housing part 117, and the three parts are butted to form the entire housing 11. The handle 111 may be formed by abutting the front housing portion 115 and the middle housing portion 117, the coupling portion 113 may be formed by abutting the front housing portion 115 and the middle housing portion 117, the first accommodating portion 112 may be formed by abutting the front housing portion 115, the middle housing portion 117, and the rear housing portion 116, and the second accommodating portion 114 may be formed by abutting the middle housing portion 117 and the rear housing portion 116. The front housing part 115, the rear housing part 116, and the middle housing part 117 are fixed to one body by screws.

As shown in fig. 7, the output shaft 121 is used for mounting a saw blade 122, and the output shaft 121 drives the saw blade 122 to cut a workpiece when rotating relative to the housing 11 about the first axis 101. The output shaft 121 extends in the direction of the first axis 101. The blade 122 is a circular blade centered on the first axis 101. The saw blade 122 extends in a cutting plane, and the cutting surface produced by the saw blade 122 when cutting a workpiece also extends in the cutting plane. The cutting plane is perpendicular to the first axis 101 and the cutting plane is parallel to the first plane 102.

As shown in fig. 1 and 6, the bottom plate 13 is also formed with an opening 132 through which the saw blade 122 at least partially passes, so that the saw blade 122 can protrude to the underside of the bottom plate plane 131. When the electric circular saw 100 has the maximum cutting depth, the size of the effective cutting portion of the saw blade passing through the bottom plate 13 is maximized. Here, when the electric circular saw 100 has the maximum cutting depth, orthographic projections of the motor 14, the handle 111, and the battery pack 151 on a plane where the bottom plate plane 131 is located are arranged in order on a straight line. The orthographic projection of the motor 14, the handle 111 and the battery pack 151 on the plane of the bottom plate plane 131 means that the projection lines of the motor 14, the handle 111 and the battery pack 151 are all perpendicular to the plane of the bottom plate plane 131.

Further, in order to improve the balance performance of the electric circular saw 100, the orthographic projection of the motor 14 in the cutting plane is located outside the orthographic projection of the saw blade 122 in the cutting plane, the orthographic projection of the handle 111 in the cutting plane is located outside the orthographic projection of the saw blade 122 in the cutting plane, and the orthographic projection of the battery pack 151 in the cutting plane is also located outside the orthographic projection of the saw blade 122 in the cutting plane. The first plane 102 and the cutting plane coincide with each other as a same plane.

As shown in fig. 6 to 11, the motor 14 may be a brushless motor 14, the motor 14 includes a motor shaft 141 that can rotate around the second axis 104, and the direction of the second axis 104 of the rotation of the motor shaft 141 is parallel to the direction of the first axis 101 of the rotation of the output shaft 121. When the motor 14 is disposed in the first receiving cavity 112a and the battery pack 151 is mounted to the coupling portion 113, the motor 14 and the battery pack 151 are respectively disposed at both ends of the handle 111 in the extending direction, that is, the handle 111 is disposed between the motor 14 and the battery pack 151, thereby facilitating to improve the balance performance of the electric circular saw 100. In the present embodiment, the motors 14 are distributed on both sides of the first plane 102 and the motors 14 are also distributed on both sides of the cutting plane, that is, the first plane 102 and the cutting plane both pass through the motors 14, so as to avoid the problem that the motors 14 are arranged on one side of the first plane 102 or the cutting plane, which causes the user not to operate the electric circular saw 100 smoothly. The diameter of the motor 14 is 45mm to 65mm, and the ratio of the rated power of the electric circular saw 100 to the diameter of the motor 14 is 25W/mm or more and 35W/mm or less, and more specifically, 30W/mm.

In the present embodiment, the battery pack 151 is insertable into the coupling portion 113 along the second straight line 105, and the second straight line 105 is perpendicular to the first axis 101 direction in which the output shaft 121 rotates. When the floor plane 131 and the first axis 101 are parallel to each other and the portion of the saw blade 122 protruding to the lower side of the floor plane 131 is the largest, the direction of the second straight line 105, in which the battery pack 151 is inserted into the coupling portion 113, obliquely intersects the floor plane 131. When the battery packs 151 are inserted into the connection portions 113, the battery packs 151 are disposed on both sides of the first plane 102 and the battery packs 151 are disposed on both sides of the cutting plane, that is, the first plane 102 and the cutting plane pass through the battery packs 151, so as to prevent the battery packs 151 from being disposed on one side of the first plane 102 or the cutting plane, thereby preventing a user from being unable to smoothly operate the electric circular saw 100. Further, the battery pack 151 is also disposed symmetrically with respect to the first plane 102, thereby facilitating an improvement in balance performance of the electric circular saw 100. In addition, in the present embodiment, the first receiving portion 112 and the coupling portion 113 are respectively disposed at both sides of the second plane 107, so that the motor 14 and the battery pack 151 are respectively disposed at both sides of the second plane 107 when the battery pack 151 is inserted into the coupling portion 113. The first receiving portion 112, the handle 111, and the coupling portion 113 are sequentially arranged in a first line 103 direction perpendicular to the first axis 101, so that the motor 14, the handle 111, and the battery pack 151 are also sequentially arranged substantially in the first line 103 direction when the battery pack 151 is inserted into the coupling portion 113. It is understood that in other embodiments, the motor 14, the handle 111, and the battery pack 151 may be sequentially arranged in a circumferential direction around the saw blade 122 and centered on the first axis 101.

In the present embodiment, the coupling portions 113 are distributed on both sides of the first plane 102 and the coupling portions 113 are also distributed on both sides of the cutting plane, that is, the first plane 102 and the cutting plane both pass through the coupling portions 113, so as to avoid the problem that the user cannot smoothly operate the electric circular saw 100 due to the coupling portions 113 being disposed on one side of the first plane 102 or the cutting plane.

In this embodiment, the housing 11 further includes a shroud assembly 16. The shield assembly 16 includes a fixed shield 161 and a movable shield 161, the fixed shield 161 is fixed with respect to the housing 11, and the movable shield 161 is rotatable with respect to the housing 11 about the first axis 101. The fixed shield 161 is fixedly connected with the housing 11, and the fixed shield 161 is also disposed on the upper side of the bottom plate plane 131. The movable shield 161 is rotatably connected to the housing 11 about the first axis 101, and the movable shield 161 at least partially extends below the bottom plate plane 131. When the movable shield 161 rotates relative to the housing 11, a gap 163 exposing the saw blade 122 is formed between the movable shield 161 and the fixed shield 161, and the gap 163 gradually increases as the movable shield 161 rotates. In the present embodiment, the motor 14 is also located on the upper side of the saw blade 122, and further, the motor 14 is also located on the upper side of the positioning guard 161. In this embodiment, the notch 163 and the motor 14 are disposed on the same side of the second plane 107, while the battery pack 151 is located on the other side of the plane.

The distance between the second axis 104 of rotation of the motor 14 and the first axis 101 of rotation of the output shaft 121 is greater than the radius of the circular saw blade 122, and further, the distance between the second axis 104 and the first axis 101 is greater than or equal to 50mm and less than or equal to 120mm, which makes the distance between the motor 14 and the output shaft 121 large, so that it is necessary to provide a transmission 17 for achieving transmission of power between the motor shaft 141 and the output shaft 121.

As shown in fig. 7-12, the transmission 17 includes a belt drive assembly 171 and a gear drive assembly 172, although it is understood that in other embodiments, the transmission 17 may include only the belt drive assembly 171 or only the gear drive assembly 172. Specifically, in the present embodiment, the belt driving unit 171 is disposed in the second accommodating chamber 114a formed in the second accommodating portion 114, and the belt driving unit 171 specifically includes: a first pulley 171a, a second pulley 171b, a drive belt 171c and an intermediate shaft 171 d. The first pulley 171a is fixedly connected to the motor shaft 141, the second pulley 171b is fixedly connected to the intermediate shaft 171d, and the transmission belt 171c is stretched over the first pulley 171a and the second pulley 171b, thereby achieving power transmission. The intermediate shaft 171d extends in a direction of a third axis 106 parallel to the first axis 101, and when the motor shaft 141 rotates, the transmission belt 171c drives the second pulley 171b to rotate, and the second pulley 171b drives the intermediate shaft 171d to rotate together with the third axis 106. The gear assembly 172 includes: the first gear 172a is fixedly connected to the intermediate shaft 171d, and the second gear 172b is connected to the output shaft 121, and the first gear 172a can transmit the power output by the intermediate shaft 171d to the output shaft 121, thereby driving the output shaft 121 to rotate about the first axis 101. In the present embodiment, the first gear 172a and the second gear 172b are meshed with each other, and it is understood that in other embodiments, a gear for enabling the user to transmit power between the first gear 172a and the second gear 172b may be further disposed therebetween.

As shown in fig. 9, the electric power tool further includes a locking member 123 for locking the rotation of the output shaft 121, and the locking member 123 can lock the rotation of the output shaft 121 when cooperating with any one of the rotating components in the transmission 17 to lock the rotation of the component, or the locking member 123 can cooperate directly with the motor shaft 141 or the output shaft 121 to lock the rotation of the output shaft 121. In the present embodiment, on the other hand, the second pulley 171b is formed with the locking groove 171e, and the locking groove 171e is recessed inward in a radial direction perpendicular to the third axis 106. The locking member 123 is partially disposed in the second receiving cavity 114a formed in the second receiving portion 114, and the locking member 123 is formed with a locking protrusion 123a capable of being inserted into the locking groove 171e, and the locking member 123 is capable of rotating with respect to the housing 11. When the user operates the locking member 123 to rotate relative to the housing 11, the locking protrusion 123a is fitted into the locking groove 171e to lock the rotation of the second pulley 171b, and the rotation of the output shaft 121 is locked.

As shown in fig. 12 and 14, in the present embodiment, the circuit board assembly 18 includes: the first circuit board 181 and the second circuit board 182, and the control circuit of the electric circular saw 100 may be partially disposed on the first circuit board 181 and partially disposed on the second circuit board 182, so that the sizes of the first circuit board 181 and the second circuit board 182 are all small, thereby preventing the problem that the circuit boards are not conveniently disposed due to the large size of the circuit boards caused by disposing all the control circuits on one circuit board, and further facilitating disposing the first circuit board 181 and the second circuit board 182 at appropriate positions in the housing 11. Furthermore, the first circuit board 181 is used for controlling the output power of the motor 14, and the second circuit board 182 can be used for controlling the battery pack 151, but not limited thereto.

In the present embodiment, the first circuit board 181 is disposed in the second receiving cavity 114a formed by the second receiving portion 114, and the first circuit board 181 extends along one plane perpendicular to the first axis 101. Still further, the transmission assembly and the motor 14 are disposed on the same side of the first circuit board 181, and more specifically, the second pulley 171b is disposed between the first circuit board 181 and the first pulley 171 a. The second circuit board 182 is disposed at the coupling portion 113 at one end of the handle 111, and the second circuit board 182 extends in a plane parallel to the direction of the second line 105 and parallel to the direction of the first axis 101. In this way, the first circuit board 181 and the second circuit board 182 can be made to efficiently utilize the internal space of the housing 11, and thus can contribute to downsizing of the housing 11. In fact, in other embodiments, when the control circuits are all disposed on one circuit board, the circuit board may be disposed at the joint portion 113 and also disposed in the second accommodation chamber 114 a.

As shown in fig. 9 to 11, the heat dissipating assembly 19 includes: the motor 14 includes a fan 191 and a heat dissipation plate 192, the fan 191 generates a heat dissipation airflow for dissipating heat of the motor 14 when the fan 191 rotates, and a heat dissipation rib 192a for guiding a flow direction of the heat dissipation airflow is formed on the heat dissipation plate 192.

The fan 191 is disposed in the first receiving chamber 112a formed by the first receiving portion 112, and the fan 191 is fixedly mounted to the motor shaft 141 to be rotated in synchronization with the motor shaft 141. The fan 191 may be a centrifugal fan 191 in the present embodiment. The first receiving parts 112 are distributed on both sides of the first plane 102, a portion of the first receiving part 112 located on the front side of the first plane 102 may be defined as a front part 112b, a portion of the first receiving part 112 located on the rear side of the first plane 102 may be defined as a rear part 112c, and the fan 191 is disposed in a space surrounded by the front part 112 b.

The heat dissipation plate 192 is disposed in the second receiving cavity 114a formed in the second receiving portion 114, and in the present embodiment, the heat dissipation plate 192 may be fixedly coupled to the first circuit board 181. More specifically, heat sink plate 192 extends in a plane perpendicular to first axis 101, and heat sink plate 192 is located on the rear side of blade 122.

As shown in fig. 1 to 2, in order to generate a heat dissipation airflow capable of dissipating heat from the motor 14 and the circuit board assembly 18, the housing 11 is further formed with a first airflow inlet 114b and a first airflow outlet 112d, the first airflow inlet 114b communicates with the inside and the outside of the housing 11, and the first airflow outlet 112d also communicates with the inside and the outside of the housing 11, so that when the fan 191 rotates, a heat dissipation airflow flowing from the first airflow inlet 114b into the housing 11 and then flowing out to the outside of the housing 11 through the first airflow outlet 112d is generated. In the present embodiment, the first airflow inlet 114b and the first airflow outlet 112d are positioned on the housing 11 such that the heat dissipation airflow can flow through at least the heat dissipation plate 192, the actuator 17, and the motor 14, thereby dissipating heat from the first circuit board 181, the actuator 17, and the motor 14. Specifically, the first airflow inlet 114b is provided on the second accommodating portion 114, and in the present embodiment, the position of the first airflow inlet 114b on the second accommodating portion 114 corresponds to the position of the first circuit board 181, so that the heat dissipation airflow flowing into the housing 11 from the first airflow inlet 114b can first flow into the first circuit board 181. The heat dissipation plate 192 and the first circuit board 181 are disposed in a flow path of the heat dissipation airflow in the housing 11, and more specifically, the heat dissipation plate 192 and the first circuit board 181 are disposed in a position closest to the first airflow inlet 114b in the flow path of the heat dissipation airflow, that is, in the flow path of the heat dissipation airflow, the heat dissipation plate 192 is closer to the first airflow inlet 114b with respect to the motor 14, and the first circuit board 181 is also closer to the first airflow inlet 114b with respect to the motor 14. In fact, the position of the first air inlet 114b on the housing 11 is only required to satisfy the requirement that the heat dissipation air flow entering the housing 11 from the first air inlet 114b can flow through the first circuit board 181, the transmission 17 and the motor 14, i.e. the requirement of the electric circular saw 100 for heat dissipation effect is satisfied.

Since the fan 191 is provided on the front portion 112b of the first accommodating portion 112 on the front side of the first plane 102 and the position of the fan 191 in the first accommodating chamber 112a also corresponds to the front portion 112b, the first air flow outlet 112d is provided on the front portion 112b of the first accommodating portion 112, and the first air flow outlet 112d can be opened at least downward on the front portion 112b of the first accommodating portion 112, so that the heat dissipating air flow flowing out from the first air flow outlet 112d can be blown to the bottom plate 13 and the vicinity of the bottom plate 13, whereby the work and the dust on the bottom plate 13 can be blown away, and the cutting accuracy can be improved. More specifically, the first air flow outlet 112d is provided on the side of the front portion 112b close to the bottom plate 13, and the first air flow outlet 112d is not provided on the upper side of the front portion 112b far from the bottom plate 13, so that it is possible to prevent the heat radiation air flow having a high temperature from being blown to the user. Similarly, the position of the first airflow outlet 112d on the housing 11 is only required to satisfy the condition that the heat dissipation airflow flowing out of the housing 11 from the first airflow outlet 112d can flow through the first circuit board 181, the transmission 17 and the motor 14. In order to improve the heat dissipation effect, a second airflow inlet 112e is further provided on a rear portion 112c of the first accommodation portion 112, which is located at the rear side of the first plane 102, so as to improve the flow rate of the heat dissipation airflow entering the housing 11. The heat radiation airflow entering the housing 11 from the second airflow inlet 112e can flow through the motor 14, so that the heat radiation effect on the motor 14 can be improved.

The electric circular saw 200 of the second embodiment shown in fig. 15 is different from the electric circular saw 100 of the first embodiment only in the heat radiating plate 292 and the second pulley 272b, and other parts of the first embodiment which can be adapted to this embodiment can be applied to this embodiment. In the present embodiment, the heat radiating plate 292 is disposed between the motor 24 and the transmission 27, and more specifically, the heat radiating plate 292 is disposed between the first pulley 271a and the second pulley 272b, so that the space between the first pulley 271a and the second pulley 272b can be effectively utilized, and thus, the heat radiating air flows through the second pulley 272b, the heat radiating plate 292, the first pulley 271a, and the motor 24 in sequence. The second pulley 272b is formed with fan blades 272f to increase the flow rate of the heat-dissipating airflow.

The electric circular saw 300 of the third embodiment shown in fig. 16 is different from the electric circular saw 100 of the first embodiment only in the heat radiating plate 392, and other parts of the first embodiment which can be adapted to this embodiment can be applied to this embodiment. In this embodiment, heat radiating plate 392 extends in a direction parallel to second axis 304 along which motor shaft 341 rotates, heat radiating plate 392 extends in a direction perpendicular to the cutting plane of saw blade 322, and heat radiating plate 392 is positioned on the right side of saw blade 322.

The electric circular saw 400 of the fourth embodiment shown in fig. 17 is different from the electric circular saw 100 of the first embodiment only in the difference of the transmission means, and other parts of the first embodiment which can be adapted to the present embodiment can be applied to the present embodiment. In this embodiment, the transmission device includes: a gear assembly 471 for power transmission between the intermediate shaft 471d and the motor shaft 441, wherein the gear assembly 471 includes a first gear 471a rotating synchronously with the motor shaft 441 and a second gear 471b rotating synchronously with the intermediate shaft 471d, and an intermediate gear 471c for power transmission between the first gear 471a and the second gear 471b can be arranged between the two gears.

The electric circular saw 500 of the fifth embodiment shown in fig. 18 is different from the electric circular saw 100 of the first embodiment only in the motor 54 and the battery pack 551, and other parts of the first embodiment which can be adapted to the present embodiment may be applied to the present embodiment. In the present embodiment, the first accommodating portion 512 and the coupling portion 513 are formed at both ends of the handle portion 511 in the extending direction, the motor 54 is disposed in the first accommodating portion 512, and the battery pack 551 is inserted into the coupling portion 513. Wherein the direction of the second axis 504 of rotation of the motor shaft 541 and the cutting plane in which the saw blade 522 extends are parallel to each other, and when the base plate 53 is in the initial state shown in fig. 18, the direction of the second axis 504 of rotation of the motor shaft 541 obliquely intersects the base plate plane 531. The direction of the second straight line 505 in which the battery pack 551 is inserted into the coupling portion 513 is parallel to the cutting plane and parallel to the bottom plate plane 531. Of course, it is understood that the installation position and the insertion direction of the battery pack 551 are not limited to this when the extension direction of the motor shaft 541 is fixed, and the extension direction of the motor shaft 541 is also limited to this when the installation position and the insertion direction of the battery pack 551 are fixed.

The electric circular saw 600 of the sixth embodiment shown in fig. 19 is different from the electric circular saw 100 of the first embodiment only in the motor 64 and the battery pack 651, and other parts of the first embodiment which can be adapted to this embodiment can be applied to this embodiment. In the present embodiment, the first receiving portion 612 and the coupling portion 613 are formed at both ends of the handle portion in the extending direction, the motor 64 is disposed in the first receiving portion 612, and the battery pack 651 is inserted into the coupling portion 613. Wherein the second axis 604 of rotation of the motor shaft 641 is parallel to the cutting plane of the saw blade 622, and when the base plate 63 is in the initial state shown in fig. 18, the second axis 604 of rotation of the motor shaft 641 is perpendicular to the base plate plane 631. The battery pack 651 is inserted into the coupling portion 613 in a direction perpendicular to the cutting plane and parallel to the bottom plate plane 631. Of course, it is understood that the installation position and the insertion direction of the battery pack 651 are not limited to this when the extension direction of the motor shaft 641 is fixed, and the extension direction of the motor shaft 641 is also limited to this when the installation position and the insertion direction of the battery pack 651 are fixed.

The electric circular saw 700 of the seventh embodiment shown in fig. 20 is different from the electric circular saw 100 of the first embodiment only in the power supply device, and other parts of the first embodiment which can be adapted to the present embodiment can be applied to the present embodiment. In the present embodiment, one end of the handle portion 711 in the extending direction forms a first accommodating portion 712, the motor 74 is disposed in the first accommodating portion 712, while the other end of the handle portion 711 in the extending direction is connected with a power cord 713, and a plug 713a for introducing commercial power is disposed at the tail end of the power cord 713 away from the handle portion 711.

The electric circular saw 800 of the eighth embodiment shown in fig. 21 is different from the electric circular saw 100 of the first embodiment only in the positions of the motor 84 and the battery pack 851, and other parts of the first embodiment which can be adapted to this embodiment may be applied to this embodiment. In this embodiment, the battery pack 851 is disposed at the left side of the advancing direction of the electric circular saw 800, and the motor 84 is disposed at the right side of the electric circular saw 800 close to the user, that is, in this embodiment, the positions of the motor 84 and the battery pack 851 are reversed with respect to the first embodiment, and at this time, the notch 863 formed by the battery pack 851 and the cover assembly 86 is located at the same side perpendicular to the cutting plane, and the motor 84 is located at the other side. Correspondingly, one end of the handle portion 811 in the extending direction thereof near the advancing direction of the electric circular saw 800 is formed with a coupling portion 813 for coupling with the battery pack 851, and the other end of the handle portion 811 in the extending direction thereof is formed with a first accommodating portion 812 for accommodating the motor 84.

The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It should be understood by those skilled in the art that the above embodiments do not limit the present invention in any way, and all technical solutions obtained by using equivalent alternatives or equivalent variations fall within the scope of the present invention.

Claims

1. An electric circular saw comprising:

the output shaft is used for mounting the saw blade;

the motor comprises a motor shaft for driving the output shaft to rotate;

the transmission device is used for realizing power transmission between the motor shaft and the output shaft;

a locking member arranged to cooperate with any one of the rotatable parts of the transmission to lock rotation of the part;

the transmission includes a belt drive assembly, the belt drive assembly including:

the first belt wheel is connected with the motor shaft;

an intermediate shaft arranged in parallel with the output shaft;

a second pulley connected to the intermediate shaft;

a drive belt tensioned over the first pulley and the second pulley;

wherein the locking member is at least partially disposed between the first pulley and the second pulley.

2. The electric circular saw of claim 1, wherein the lock cooperates with the second pulley to lock the second pulley.

3. The electric circular saw of claim 2, wherein the second pulley has a locking groove formed thereon, and the locking member includes a locking protrusion capable of being inserted into the locking groove.

4. The electric circular saw of claim 3, wherein the locking groove is recessed inward in a radial direction perpendicular to a rotational axis of the intermediate shaft.

5. The electric circular saw of claim 1, further comprising a housing including a first receptacle for receiving the motor and a second receptacle for receiving the belt drive assembly, the locking member being at least partially disposed within the second receptacle.

6. The electric circular saw of claim 1, further comprising a housing including a first receiving portion for receiving the motor, the first receiving portion including a front portion disposed at a front side of the saw blade and a rear portion disposed at a rear side of the saw blade, the motor being a brushless motor, the fan being fixedly mounted to the motor shaft.

7. The electric circular saw of claim 6, wherein the fan is disposed within the front portion, the front portion having an airflow outlet disposed thereon.

8. An electric circular saw comprising:

the output shaft is used for mounting the saw blade;

the motor comprises a motor shaft for driving the output shaft to rotate;

the transmission device includes:

the first belt wheel is connected with the motor shaft;

the intermediate shaft is arranged in parallel with the output shaft;

a second pulley connected to the intermediate shaft;

a drive belt tensioned over the first pulley and the second pulley;

wherein the electric circular saw further comprises a gear transmission assembly disposed between the intermediate shaft and the output shaft.

9. The electric circular saw of claim 8, wherein a plane in which the saw blade is located defines a cutting plane, and an orthographic projection of the motor in the cutting plane is located outside an orthographic projection of the saw blade in the cutting plane.

10. The electric circular saw of claim 8, wherein the gear assembly includes a first gear fixedly connected to the intermediate shaft and a second gear connected to the output shaft, the first gear being capable of transmitting power output by the intermediate shaft to the output shaft.