WO2023024738A1

WO2023024738A1 - Cutting tool

Info

Publication number: WO2023024738A1
Application number: PCT/CN2022/105244
Authority: WO
Inventors: 徐中全
Original assignee: 南京泉峰科技有限公司
Priority date: 2021-08-25
Filing date: 2022-07-12
Publication date: 2023-03-02
Also published as: CN115921985A

Abstract

A cutting tool, comprising: a machine shell (10) provided with a storage cavity (11) and a gripping part (12) to be gripped by a user; a power assembly (20) located in the storage cavity (11) and used for providing a driving force; a gearbox (30) at least partially located in the storage cavity (11); a transmission assembly (40) at least partially located in the gearbox (30) and connected to the power assembly (20); a reciprocating assembly (50) located in the gearbox (30) and connected to the transmission assembly (40), wherein the reciprocating assembly (50) is configured to move in a reciprocating manner relative to the machine shell (10), and the reciprocating assembly (50) comprises a mounting part (62) that can be used for mounting a cutting accessory; and a first supporting piece (60) mounted on a front end of the machine shell (10) and used for supporting a workpiece, wherein the ratio of the distance between a rear end of the gearbox (30) and a front end of the first supporting piece (60) to a reciprocating stroke of the reciprocating assembly (50) is larger than or equal to 4 and less than or equal to 9.

Description

cutting tool

This application claims the priority of a Chinese patent application with application number 202110978804.9 filed with the China Patent Office on August 25, 2021, the entire content of which is incorporated herein by reference.

technical field

The present application specifically relates to a cutting tool, in particular to a cutting tool.

Background technique

A reciprocating saw is a cutting tool for sawing with a reciprocating saw blade. It is a kind of electric saw. It is often used for sawing metal sheets, pipes, profiles or cutting bevels on steel pipes. Of course, it can also cut cables or other non-woven products. Metal materials are generally composed of a casing, a motor, a transmission mechanism, and a saw blade. The torque of the motor is converted into the linear reciprocating motion of the saw blade through the transmission mechanism to achieve cutting.

Generally, reciprocating saws can be divided into one-handed reciprocating saws and two-handed reciprocating saws according to usage habits. The one-handed reciprocating saw requires the user to operate with one hand, so the performance parameters such as the compactness of the whole machine structure and the overall weight affect the user's experience to a large extent.

Contents of the invention

In order to solve the deficiencies of the related technologies, the purpose of this application is to provide a cutting tool with a reasonable arrangement of the whole machine, a compact structure and a lighter weight.

In order to achieve the above goals, the application adopts the following technical solutions:

A cutting tool, comprising: a housing formed with an accommodating cavity and a grip portion for a user to hold; a power assembly located in the accommodating cavity for providing driving force; a gear box at least partially located in the accommodating cavity Inside; a transmission assembly, at least partially located in the gearbox, connected to the power assembly; a reciprocating assembly, located in the gearbox, connected to the transmission assembly, and the reciprocating assembly is arranged opposite to the casing Reciprocating movement, the reciprocating assembly includes a mounting part that can be used to install cutting accessories; a first support member is installed at the front end of the casing to support the cutting workpiece; wherein, the rear end of the gear box is connected to the first The ratio of the distance between the front end of the support member and the reciprocating stroke of the reciprocating assembly is greater than or equal to 4 and less than or equal to 9.

In one embodiment, the transmission assembly includes: a driving wheel connected to the power assembly; a driven wheel internally meshing with the driving wheel and capable of being driven by the driving wheel to rotate around a first axis.

In one embodiment, the reciprocating assembly includes: a reciprocating rod, which is a full-length flat piece; a balance weight, which is arranged in the gear box and can reciprocate in the gear box to balance the Describe the movement of reciprocating components.

In one embodiment, the balance weight is located at the lowermost end of the gearbox.

In one embodiment, it further includes: a first driving member, connected to the driven wheel, capable of being driven by the driven wheel, to drive the balance weight to reciprocate in the gear box along the axis of the fuselage;

The second supporting member is located in the gear box and at least supports the first driving member and the reciprocating rod.

In one embodiment, the upper end of the second support member is recessed inwardly to form: a first guide groove for supporting and guiding the reciprocating rod to reciprocate in the gearbox along the axis of the fuselage; a receiving part for accommodating the first driving part; a second guide slot for guiding the balance weight to reciprocate in the gearbox along the axis of the fuselage; the lower end of the second supporting part faces The inner depression is formed with: a third guide groove, used to cooperate with the second guide groove to guide the reciprocating movement of the balance weight.

In one embodiment, the second support member is formed with a ventilation channel; the housing of the gear box is provided with a ventilation hole corresponding to the port of the ventilation channel.

In one embodiment, the first driving member is a driving cam; the driving cam includes a first portion with a first depth and a second portion with a second depth.

In one embodiment, it also includes: a first connecting pin, fixed on the driven wheel, and passing through the first installation hole on the first part of the driving cam; a second connecting pin, passing through the second mounting hole of the driving cam. The second mounting hole on the part can rotatably fix the driving cam in the gear box.

In one embodiment, the balance weight is formed with: a second receiving portion for receiving the second portion of the driving cam.

In one embodiment, it further includes: a support assembly, arranged between the power assembly and the driven wheel, for supporting the power assembly and/or the driven wheel.

In one embodiment, the supporting assembly includes: a fixing part, located in the accommodating cavity, for fixing the power assembly; a supporting shaft, located on the driven wheel, for supporting the driven wheel; a supporting bearing , installed on the support shaft; a pressing piece, located at the lower end of the supporting bearing; a third connecting pin, used to fix the fixing piece, and connect the supporting bearing and the pressing piece through the driven wheel Fastened to the driven wheel.

In one embodiment, the power assembly includes a motor; the motor is located at the front end or the rear end of the accommodating cavity.

A cutting tool, comprising: a housing formed with an accommodating cavity and a grip portion for a user to hold; a power assembly located in the accommodating cavity for providing driving force; a gear box located in the accommodating cavity; The transmission assembly is located in the gear box and is connected to the power assembly; the reciprocating assembly is located in the gear box and is connected to the transmission assembly, and the reciprocating assembly is set to reciprocate relative to the casing. The reciprocating assembly includes a mounting part that can be used to install cutting accessories; a first support member is installed at the front end of the casing to support the cutting workpiece; wherein: the transmission assembly includes: a driving wheel connected to the power assembly The driven wheel is internally meshed with the driving wheel and can be driven by the driving wheel to rotate around the first axis.

A cutting tool, comprising: a housing formed with an accommodating cavity and a grip portion for a user to hold; a power assembly located in the accommodating cavity for providing driving force; a gear box located in the accommodating cavity; a transmission assembly, at least partially located in the gear box, connected to the power assembly; a reciprocating assembly, at least partially located in the gear box, connected to the transmission assembly, the reciprocating assembly is disposed opposite to the casing Reciprocating movement, the reciprocating assembly includes a mounting part that can be used to install cutting accessories; the first support member is installed at the front end of the casing to support the cutting workpiece; wherein the reciprocating assembly includes: a reciprocating rod, the The reciprocating rod is a full-length flat part that can reciprocate along the axial direction of the fuselage; the balance weight is arranged at the lowermost end of the gear box and can reciprocate in the gear box.

In one embodiment, the cutting tool further includes: a second driving member, disposed between the reciprocating rod and the balance weight, capable of being driven by the reciprocating rod, and driving the balance weight to rotate on the gear The reciprocating movement is performed inside the box to balance the movement of the reciprocating assembly.

In one embodiment, the lower end surface of the reciprocating rod has first transmission teeth; the upper end surface of the balance weight is provided with second transmission teeth; the second driving member is arranged between the reciprocation rod and the balance weight between them, meshing with the first transmission tooth and the second transmission tooth respectively, can be driven by the reciprocating rod, and drive the balance weight to reciprocate in the gearbox to balance the reciprocating assembly sports.

In one embodiment, it further includes: a fourth connecting pin for connecting the driven wheel and the reciprocating rod, so that the driven wheel can drive the reciprocating rod to perform reciprocating motion.

In one embodiment, the ratio of the distance from the rear end of the gearbox to the front end of the first support member to the reciprocating stroke of the reciprocating assembly is 5.

In one embodiment, the transmission assembly includes: a driving wheel connected to the power assembly; a driven wheel meshing with the driving wheel, the diameter of the driving wheel is smaller than or equal to the inner radius of the driven wheel.

The benefit of this application lies in: the distance between the handle and the tool can be effectively shortened by adopting the internal teeth and the full-length flat design of the slide bar, thereby shortening the length of the whole machine; by optimizing the layout and structure of the components in the gearbox Adjusting the balance weight at the bottom of the gearbox can reduce the weight of the balance weight without increasing the vibration, thereby reducing the weight of the whole machine.

Description of drawings

Fig. 1 is the structural diagram of reciprocating saw in the embodiment of the present application;

Fig. 2 is a structural diagram of part of the structure in the reciprocating saw shown in Fig. 1;

Fig. 3 is a structural diagram of part of the structure in the reciprocating saw shown in Fig. 1;

Fig. 4 is a sectional view of part of the structure of the reciprocating saw shown in Fig. 3;

Fig. 5 is an exploded view of part of the structure in the reciprocating saw shown in Fig. 2;

Fig. 6 is an exploded view of part of the structure in the reciprocating saw shown in Fig. 2;

7 and 8 are structural views of the second support member in the reciprocating saw shown in FIG. 2;

Fig. 9 is a structural diagram of the drive cam in the reciprocating saw shown in Fig. 2;

Fig. 10 is a structural diagram of the driven wheel in the reciprocating saw shown in Fig. 2;

Fig. 11 is a structural diagram of the reciprocating rod in the reciprocating saw shown in Fig. 2;

Fig. 12 is a structural diagram of the lower case of the gear box in the reciprocating saw shown in Fig. 2;

Fig. 13 is a cross-sectional view of part of the structure of the reciprocating saw shown in Fig. 2;

Fig. 14 is a perspective view of an exploded view of part of the structure in the reciprocating saw in another embodiment;

Fig. 15 is another perspective view of an exploded view of a part of the structure of the reciprocating saw in another embodiment.

Reference signs:

Reciprocating saw - 100;

First axis - 101; Fuselage axis - 102;

Case-10; Accommodating cavity-11; Grip part-12;

Power assembly-20; Motor-21; Output shaft-211;

Gear box-30; Upper housing-301; Lower housing-302; Air vent-31; Support assembly-32; Fixing piece-321; Support shaft-322; Support bearing-323; Connecting pin-325; fourth accommodation part-33; floating knife lifting system-331;

Transmission assembly-40; driving wheel-41; driven wheel-42; third mounting hole-421; fourth mounting hole-422;

Reciprocating assembly-50; reciprocating rod-51; first transmission tooth-511; third accommodation part-512; balance weight-52;

The first support member-60; the plug-in-61; the installation part-62; the slider sleeve-63; the pressing piece-64; the fifth connecting pin-641;

The first driving part-70; the first part-71; the first mounting hole-711; the second part-72; the second mounting hole-721; the second driving part-701; the connecting rod-7011; the third driving part-702 ;Third drive tooth-7021;

The second support-80; the first guide groove-81; the first accommodation part-82; the second guide groove-83; the guide-831; 86;

First connecting pin-90; second connecting pin-91; fourth connecting pin-93.

Detailed ways

The present application will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

In order to clearly illustrate the technical solution of the present application, up, down, front, back, left and right as shown in FIG. 1 are defined.

As shown in FIG. 1 , it is a cutting tool of the present application, specifically an electric cutting tool. In the embodiment of the present application, a reciprocating saw 100 is taken as an example for detailed description.

As shown in FIGS. 1 to 5 , a reciprocating saw 100 at least includes: a casing 10 , a power assembly 20 , a gear box 30 , a transmission assembly 40 , a reciprocating assembly 50 , a first support 60 , a power supply device and cutting accessories. Wherein, the casing 10 is formed with an accommodating cavity 11 and a grip portion 12 for a user to grip. The accommodating cavity 11 accommodates the power assembly 20 , the gear box 30 , the transmission assembly 40 and the reciprocating assembly 50 . The first support member 60 is located at the front end of the reciprocating saw, for example, installed at the front end of the casing 10 , and is mainly used to resist the support and cut the workpiece. The power supply unit is installed on the casing 10, and as an energy source for the reciprocating saw, the power supply unit may be a battery pack.

In a specific implementation, the power assembly 20 includes a motor 21, and the motor 21 may be a brushless non-inductive motor or a brushless inductive motor, which is not limited here. A driving wheel 41 is arranged on the output shaft of the motor 21, and the driving wheel 41 goes deep into the gearbox 30 and meshes with the driven wheel 42 in the gearbox 30, so that the driving wheel 41 on the output shaft can drive the driven wheel under the drive of the motor 42 rotate around the first axis 101 to drive the reciprocating assembly 50 in the gear box 30 to reciprocate along the direction of the fuselage axis 102, and then drive the cutting attachment to perform reciprocating cutting action. In this embodiment, as shown in Figure 6 and Figure 10, the driven wheel 42 is a ring gear and the transmission teeth of the driven wheel 42 are located inside the ring gear, and the driving wheel 41 is entirely or partially located inside the gear of the driven wheel 42, and The driven wheel 42 is internally meshed. Compared with the traditional externally-engaged transmission assembly 40 , the internally-engaged transmission assembly 40 can effectively shorten the length of the whole machine, and the length of the entire machine can be shortened by about 10mm-15mm in the direction of the fuselage axis 102 . It should be noted that the diameter of the driving wheel 41 is smaller than or equal to the inner radius of the driven wheel 42 , so that the driving wheel 41 can engage in the ring gear of the driven wheel 42 .

In one embodiment, as shown in FIGS. 3-6 , a support assembly 32 is also included, which can more stably arrange the support motor on the upper end of the gear box 30 . In a specific implementation, the support assembly 32 includes: a fixing piece 321 , which is used to fix the motor in the accommodation chamber 11 , and is specifically used to fix the motor above the gear box 30 . In an optional implementation, the support shaft 322 is connected to the fixing member 321, and the support shaft 322 goes deep into the inner ring gear of the driven wheel 42, and a support bearing 323 and a pressing member 324 are sequentially arranged on the support shaft 322 from top to bottom, The third connecting pin 325 passes through the fixing member 321 , the pressing member 324 and the fourth installation hole 422 of the driven wheel 42 from top to bottom in order to fix the driven wheel 42 in the gearbox 30 . It can be seen from the above that the third connecting pin 325 is also connected to the fixing member 321 fixing the motor 21 while fixing the driven wheel 42 . That is to say, the connecting pins for fixing the motor 21 and the connecting pins for fixing the support bearing 323 can be used in common, thereby saving the use space of the connecting pins in the gearbox 30 . It should be noted that since the support bearing 323 is partly or completely located inside the ring gear of the driven wheel 42, the installation height of the motor is reduced to a certain extent, thereby reducing the height of the whole machine.

In this embodiment, the output shaft 211 of the motor 21 and the support shaft 322 of the support assembly 32 are substantially parallel to each other.

In one embodiment, the driving wheel 41 is internally meshed with the rear end of the inner ring gear of the driven wheel 42 , and the motor 21 is located at the upper rear of the driven wheel 42 as a whole.

In one embodiment, the driving wheel 41 is internally engaged with the front end of the inner ring gear of the driven wheel 42 , and the motor 21 is located at the upper front of the driven wheel 42 as a whole.

In this embodiment, the gear box 30 may include an upper casing 301 and a lower casing 302, and the upper and lower casings are fixed by rivets. The above-mentioned driving wheel 41 is located in the gear box 30 as a power output member directly meshing with the driven wheel 42 ; As shown in FIG. 6 , the gearbox 30 includes an upper casing 301 , a driving wheel 41 , a support assembly 32 , a driven wheel 42 , a reciprocating assembly 50 and a lower casing 302 from top to bottom. Wherein, the reciprocating assembly 50 includes a reciprocating rod 51 and a balance weight 52 , and a first driving member 70 and a second supporting member 80 are further provided between the reciprocating rod 51 and the balancing weight 52 . In the specific implementation, the first connecting pin 90 is also included: the first connecting pin 90 is fixed on the driven wheel 42 through the third mounting hole 421 on the driven wheel 42, and passes through the third mounting hole 421 sequentially from top to bottom, reciprocating The tail connection hole of the rod 51 and the first installation hole 711 on the first driving member 70 . Thereby, the rotation of the driven wheel 42 can drive the first connecting pin 90 to rotate, the first connecting pin 90 rotates with the driven wheel 42 and drives the first driving member 70 to rotate, and the reciprocating rod 51 can move along the first driving member 70 driven by the first driving member 70. The first guide groove 81 on the second supporting member 80 can reciprocate, that is, can reciprocate along a direction substantially parallel to the axis 102 of the fuselage.

In this embodiment, the reciprocating rod 51 is a full length flat member. That is to say, the reciprocating rod 51 is a flat part as a whole, and part or all of the reciprocating rod 51 is accommodated in the first guiding groove 81 formed by inwardly recessing the second supporting member 80 . In the present application, an insert 61 is provided on the lower housing 302 , and the front end of the second support member 80 and the front end of the reciprocating rod 51 pass through the insert 61 . That is, the insert 61 can further guide or stabilize the reciprocating motion of the reciprocating rod 51 . Optionally, a pressing piece 64 is also provided at the front end of the second supporting member 80, and there are two installation holes on the pressing piece 64, and the guide 831 can pass through the above two installation holes to fix the pressing piece 64 on the reciprocating rod 51 To enhance the stability of the reciprocating movement of the reciprocating rod 51.

In some embodiments, the reciprocating rod does not include a cylindrical portion extending in the reciprocating direction.

In some embodiments, the upper surface of the reciprocating rod extends in a first plane from the front end to the rear end, and the lower surface extends in a second plane from the front end to the rear end.

A plug-in 61 is provided between the first support member 60 and the reciprocating rod 51. The front end of the reciprocating rod 51 passes through the plug-in 61 and is fixedly connected to the installation part 62, which is used for installing cutting accessories. Cutting accessories are generally saw blades or other types of cutting elements. When the tool is in operation, the first support member 60 can abut against the cutting workpiece to prevent the cutting workpiece from sliding. In addition, a slider sleeve 63 is also fixed on the front end of the reciprocating rod 51 . Since the entire length of the reciprocating rod 51 is flat, the slider cover 63 at the front end of the slider 51 can be set shorter, thereby increasing the reciprocating stroke of the reciprocating rod 51 . The so-called reciprocating stroke refers to the maximum distance that the reciprocating rod 51 can move during the working process of the reciprocating saw 100 . It can be understood that due to the flat design of the full length of the reciprocating rod 51, the distance L1 between the rear end of the gearbox 30 and the front end of the first support member 60 can be shortened to a certain extent on the basis of the same reciprocating formation, thereby reducing the overall machine. The length ensures the compact structure of the whole machine.

In the embodiment of the present application, instead of the external meshing of the driving wheel 41 and the driven wheel 42, the driving wheel 41 of the pinion is internally meshed with the ring gear of the driven wheel 42, and combined with the full-length flat slider 51, it can be achieved The ratio of the distance between the rear end of the gear box 30 to the front end of the first support member 60 and the reciprocating stroke of the reciprocating rod 51 is greater than or equal to 4 and less than or equal to 9. For example, the ratio of the distance between the rear end of the gearbox 30 to the front end of the first support member 60 and the reciprocating stroke of the reciprocating rod 51 may be 4, 5, 6, 7, 8, 9, etc. For example, the ratio of the distance from the rear end of the gearbox 30 to the front end of the first support member 60 to the reciprocating stroke of the reciprocating rod 51 may be 5.

In an optional implementation, as shown in FIG. 9 , the first driving member 70 is a driving cam 70 , and the driving cam 70 mainly includes a first portion 71 with a first depth and a second portion 72 with a second depth. Wherein, the first part 71 is provided with a first installation hole 711 , and the second part 72 is provided with a second installation hole 721 . Optionally, the first depth is smaller than the second depth. It can be seen from the above that the first mounting hole 711 is mounted with the first connecting pin 90 . The second mounting hole 721 is installed with the second connecting pin 91 , and the second connecting pin 91 can rotatably fix the driving cam 70 in the gear box 30 . In addition, since the second receiving portion 521 in the balance weight 52 can accommodate the second portion 72 of the driving cam 70 , it can be considered that the second connecting pin 91 passes through the balance weight 52 . That is to say, the driving cam 70 can rotate around the second connecting pin 91 , and the second portion 72 of the driving cam 70 can drive the balance weight 52 to reciprocate in the gear box 30 along the fuselage axis 102 .

In this embodiment, as shown in FIG. 7 and FIG. 8 , the second support member 80 is a multifunctional support member. Specifically, the upper end of the second support member 80 is recessed to form a first guide groove 81 , which can support and guide the reciprocating rod 51 to reciprocate along the fuselage axis 102 in the gearbox 30 . For example, the reciprocating rod 51 may be partially or completely accommodated in the first guide groove 81 . It can be understood that the shape of the first guide groove 81 is similar to the outer contour of the reciprocating rod 51 . In this embodiment, the reciprocating rod 51 is designed in a similar "convex" shape, and the first guide groove 81 is also designed in a similar "convex" shape. Optionally, the outer contour shape of the reciprocating rod 51 may also be of other types, which is not limited here. In addition, a hollow first receiving portion 82 is formed on the concave end surface of the second supporting member 80 for receiving the first driving member 70 . It can be understood that the contour of the first receiving portion 82 is basically consistent with the outer contour of the driving cam 70 , which can ensure that the driving cam 70 is partly or completely located in the first receiving portion 82 formed by the second supporting member 80 . Further, the second support member 80 is further provided with a second guide groove 83 to guide the reciprocating movement of the balance weight 52 along the fuselage axis 102 in the gearbox 30 . It should be noted that the second guide groove 83 runs through the upper and lower end faces of the second support member 80, and the second guide groove 83 is provided with a guide piece 831, which can fix the balance weight 52, and the guide piece 831 is placed in the second guide groove. Movement within 83 can guide the movement of counterweight 52 . Further, the lower end of the second support member 80 is recessed inwardly to form a third guide groove 85 for cooperating with the second guide groove 83 to guide the reciprocating movement of the balance weight 52 .

It can be understood that the reciprocating rod 51 generates heat after reciprocating on the second support member 80 , causing the temperature of the gas in the recess of the second support member 80 and the gear box 30 to rise to a high level, which will affect the performance of the tool in the long run. In an optional implementation, a ventilation channel 84 is also formed on the second support member 80, and a ventilation hole 31 is correspondingly provided on the housing of the gear box 30, and the hot air in the gear box 30 can pass through the ventilation channel 84 and the ventilation hole 31. discharge.

In this embodiment, the ventilation passages 84 are arranged at the four corners of the reciprocating rod 51 , and the four corners of the reciprocating rod 51 are recessed toward the middle to form four ventilation passages 84 .

In this embodiment, the balance weight 52 is located under the second support member 80 , and the balance weight 52 is disposed on the lower casing of the gear box 30 , that is, the balance weight 52 is located at the bottom of the gear box 30 . Therefore, the effect of lifting the knife by torque is produced. On the basis of achieving the same force of balancing the movement of the reciprocating assembly 50, a lighter weight balance weight 52 can be selected, thereby achieving the effect of reducing the quality of the whole machine. At the same time, the effect of lifting the knife due to the torque will also improve the cutting effect of the tool to a certain extent.

In a specific implementation, as shown in FIG. 9 , a second accommodating portion 521 is formed on the balance weight 52 for accommodating the second portion 72 of the driving cam 70 . It can be understood that the front end of the balance weight 52 can also fix the guide piece 831 in the second guide slot 83 . Since the second guide member 831 is fixed on the balance weight 52, when the driving cam 70 rotates, the rotation of the second part 72 of the cam can drive the balance weight 52 to reciprocate on the second supporting frame.

In this embodiment, a fourth accommodating portion 33 for accommodating the floating vibrating tool lifting system is formed on the lower casing of the gear box 30 . The floating tool lifting system 331 can be accommodated in the fourth housing portion 33, and the single-handed cutting speed of the tool can be greatly improved by using the floating vibration lifting system. Optionally, the upper housing 301 of the gear box 30 may also be provided with an accommodating cavity for accommodating the floating knife lifting system 331 . Optionally, an accommodating chamber for accommodating the floating tool lifting system 331 may be provided on the upper and lower housings of the gear box 30 at the same time, so as to further enhance the floating tool lifting effect of the tool.

In the embodiment of the present application, the motor in the reciprocating saw cooperates with each component in the gearbox 30 to control the blade to perform reciprocating cutting. The process is as follows:

The output shaft of the motor drives the driving wheel 41 to rotate, and the driving wheel 41 meshes with the inner ring gear of the driven wheel 42 to drive the driven wheel 42 to rotate; The first guide groove 81 of a support member 60 reciprocates; the driven wheel 42 is connected with the driving cam 70 through the first connecting pin 90 at the same time, and the rotation of the driven wheel 42 can drive the driving cam 70 to rotate around the second connecting pin 91; the driving cam 70 The second part 72 of the second part 72 is accommodated in the second accommodating portion 521 of the balance weight 52 so as to drive the balance weight 52 to reciprocate along the second guide groove 83 of the first support member 60 to balance the reciprocation movement of the reciprocating rod 51 . It can be understood that the reciprocating movement directions of the reciprocating rod 51 and the balance weight 52 are basically the same.

In one embodiment, cycloidal gear transmission can be used instead of the internal meshing transmission of the driving wheel 41 and the driven wheel 42 .

In one embodiment, as shown in FIGS. 13 to 15 , part of the structure inside the gearbox 30 is different from the structure inside the gearbox 30 in the above-mentioned embodiments. It should be noted that the numbers of some components, components or components in this embodiment follow the numbers in the above embodiments. As shown in FIGS. 13-15 , the drive cam 70 is not provided in the gear box 30 . That is to say, the transmission structure for driving the balance weight 52 in this embodiment is different from that in the above-mentioned embodiments.

In a specific implementation, the fourth connecting pin 93 can connect the driven wheel 42 and the reciprocating rod 51 so that the driven wheel 42 can drive the reciprocating rod 51 to perform reciprocating motion. A second driving member 701 is arranged below the reciprocating rod 51 , and the second driving member 701 is fixed below the second driving member 80 through the fifth mounting hole 86 at the lower end of the connecting rod 7011 and the second supporting member 80 . Optionally, the lower end surface of the reciprocating rod 51 has a first transmission tooth 511, and the upper end surface of the balance weight 52 has a second transmission tooth 524. The second driving member 701 can be a driving wheel, and the driving wheel is respectively connected to the above-mentioned first transmission gear. The tooth 511 meshes with the second transmission tooth 524 . Therefore, when the reciprocating rod 51 reciprocates, it can drive the second driving member 701 to rotate, and the rotation of the second driving member 701 will drive the balance weight 52 to reciprocate. In an optional implementation manner, a third driving member 702 may also be included, the third driving member 702 is fixed in the third receiving portion 512 of the reciprocating rod 51 , and a third driving tooth 7021 is provided on the lower end surface of the third driving member 702 . During the reciprocating movement, the reciprocating rod 51 can drive the third driver 702 to reciprocate, the third driver 702 drives the second driver 701 to rotate, and the rotation of the second driver 701 drives the balance weight 52 on the second support. Do reciprocating motion in part 80.

By using the second driving member 701 to drive the balance weight 52 , the friction between the balance weight 52 and the eccentric disk 53 during the reciprocating motion is avoided, thereby reducing the heat generation in the gearbox 30 to a certain extent. When the lower end of the gear box 30 generates less heat, the lower housing of the gear box 30 made of plastic can be selected to reduce the weight of the gear box 30 .

In this embodiment, the second supporting member 80 is located below the reciprocating rod 51 , and the guiding groove or receiving portion in the second supporting member 80 is also changed correspondingly. The pressing piece 64 is fixed below the reciprocating rod 51 .

It should be noted that, in this embodiment, the configuration of other components may refer to the descriptions in the foregoing embodiments, and details are not repeated here.

Claims

A cutting tool comprising:

The casing is formed with an accommodating cavity and a grip portion for the user to grip;

a power assembly, located in the accommodating cavity, for providing driving force;

a gear box located in the accommodating chamber;

a transmission assembly, located at least partially within the gearbox, connected to the power assembly;

a reciprocating assembly, located at least partially within the gearbox, connected to the transmission assembly, the reciprocating assembly being configured to reciprocate relative to the housing, the reciprocating assembly including a mounting portion configured to mount a cutting accessory;

The first support member is installed at the front end of the casing to support the cutting workpiece;

The ratio of the distance from the rear end of the gearbox to the front end of the first support member to the reciprocating stroke of the reciprocating assembly is greater than or equal to 4 and less than or equal to 9.
The cutting tool of claim 1, wherein the transmission assembly comprises:

a driving wheel connected with the power assembly;

The driven wheel is internally meshed with the driving wheel and can be driven by the driving wheel to rotate around the first axis.
The cutting tool of claim 2, wherein the reciprocating assembly comprises:

a reciprocating rod that is a full length flat piece;

The balance weight is arranged in the gear box and can reciprocate in the gear box to balance the movement of the reciprocating assembly.
3. The cutting tool of claim 3, wherein the counterweight is located at the lowermost end of the gear case.
The cutting tool of claim 3, further comprising:

The first driving member is connected to the driven wheel and can be driven by the driven wheel to drive the balance weight to reciprocate along the axis of the fuselage in the gear box;

The second supporting member is located in the gear box and at least supports the first driving member and the reciprocating rod.
The cutting tool according to claim 5, wherein the upper end surface of the second supporting member is recessed inwardly to form:

a first guide groove, used to support and guide the reciprocating rod to reciprocate in the gearbox along the axis of the fuselage;

a first accommodating portion for accommodating the first driving member;

a second guide groove, used to guide the balance weight to reciprocate in the gearbox along the axis of the fuselage;

The lower end of the second support member is recessed inwardly to form:

The third guide groove is used to cooperate with the second guide groove to guide the reciprocating movement of the balance weight.
The cutting tool according to claim 5, wherein the second support member is formed with a ventilation channel;

Ventilation holes corresponding to ports of the ventilation channel are opened on the casing of the gear box.
The cutting tool of claim 5, wherein the first drive member is a drive cam;

The drive cam includes a first portion having a first depth and a second portion having a second depth.
The cutting tool of claim 8, further comprising:

a first connecting pin, fixed on the driven wheel, and passing through the first mounting hole on the first part of the driving cam;

The second connecting pin passes through the second installation hole on the second part of the driving cam, and can rotatably fix the driving cam in the gear box.
The cutting tool according to claim 8, wherein said counterweight is formed with:

The second accommodating part is used for accommodating the second part of the driving cam.
The cutting tool of claim 2, further comprising:

The support assembly is arranged between the power assembly and the driven wheel, and is used to support the power assembly and/or the driven wheel.
The cutting tool of claim 11, wherein the support assembly comprises:

a fixing part, located in the accommodating cavity, for fixing the power assembly;

a support shaft, located on the driven wheel, for supporting the driven wheel;

a support bearing installed on the support shaft;

a pressing piece, located at the lower end of the support bearing;

The third connecting pin is used for fixing the fixing part and passing through the driven wheel to fasten the support bearing and the pressing part to the driven wheel.
The cutting tool of claim 1, wherein the power pack includes an electric motor;

The motor is located at the front end or the rear end of the accommodating cavity.
A cutting tool comprising:

The casing is formed with an accommodating cavity and a grip portion for the user to grip;

a power assembly, located in the accommodating cavity, for providing driving force;

a gear box located in the accommodating chamber;

a transmission assembly, located at least partially within the gearbox, connected to the power assembly;

a reciprocating assembly, located at least partially within the gearbox, connected to the transmission assembly, the reciprocating assembly being configured to reciprocate relative to the housing, the reciprocating assembly including a mounting portion configured to mount a cutting accessory;

The first support member is installed at the front end of the casing to support the cutting workpiece;

The transmission assembly includes:

a driving wheel connected with the power assembly;

The driven wheel is internally meshed with the driving wheel and can be driven by the driving wheel to rotate around the first axis.
A cutting tool comprising:

The casing is formed with an accommodating cavity and a grip portion for the user to grip;

a power assembly, located in the accommodating cavity, for providing driving force;

a gear box located in the accommodating chamber;

a transmission assembly, located at least partially within the gearbox, connected to the power assembly;

a reciprocating assembly, located at least partially within the gearbox, connected to the transmission assembly, the reciprocating assembly being configured to reciprocate relative to the housing, the reciprocating assembly including a mounting portion configured to mount a cutting accessory;

The first support member is installed at the front end of the casing to support the cutting workpiece;

The reciprocating components include:

a reciprocating rod, the reciprocating rod is a full-length flat part capable of reciprocating motion along the axial direction of the fuselage;

The balance weight is arranged at the lowermost end of the gear box and can reciprocate in the gear box to balance the movement of the reciprocating assembly.
The cutting tool of claim 15, further comprising:

The second driving member is arranged between the reciprocating rod and the balance weight, can be driven by the reciprocating rod, and drives the balance weight to reciprocate in the gearbox to balance the reciprocating assembly sports.
The cutting tool according to claim 16, wherein the lower end surface of the reciprocating rod has a first transmission tooth; the upper end surface of the balance weight is provided with a second transmission tooth;

The second driving member is arranged between the reciprocating rod and the balance weight, meshes with the first transmission gear and the second transmission gear respectively, can be driven by the reciprocation rod, and drives the balance weight reciprocating motion within the gearbox to balance motion of the reciprocating assembly.
The cutting tool of claim 15, further comprising:

The fourth connecting pin is used to connect the driven wheel and the reciprocating rod, so that the driven wheel can drive the reciprocating rod to perform reciprocating motion.
The cutting tool according to claim 15, wherein the ratio of the distance from the rear end of the gear box to the front end of the first support member to the reciprocating stroke of the reciprocating assembly is 5.
The cutting tool of claim 15, wherein the transmission assembly comprises:

a driving wheel connected with the power assembly;

The driven wheel is internally meshed with the driving wheel, and the diameter of the driving wheel is smaller than or equal to the inner radius of the driven wheel.