Reciprocating saw

Abstract

The utility model particularly relates to a reciprocating saw which comprises a shell, a motor, a conveying wheel, a reciprocating assembly and a balancing weight assembly. The motor is provided with an output shaft extending in the first direction. The conveying wheel is fixed in the shell through a supporting shaft, the supporting shaft extends in the second direction, the conveying wheel is in transmission connection with the output shaft and rotates under driving of the motor, and the rotating axis of the conveying wheel is parallel to the second direction. The reciprocating assembly comprises a working shaft in transmission connection with the conveying wheel. The balancing weight assembly comprises a balancing weight in transmission connection with the conveying wheel. In the second direction, the output shaft, the conveying wheel, the working shaft and the balancing weight are sequentially arranged, the working shaft and the balancing weight are driven by the motor to reciprocate in the first direction, and the movement direction of the working shaft is opposite to that of the balancing weight. According to the reciprocating saw, the acceleration of the whole machine in the first direction and the R rotation direction can be reduced, the vibration effect of the whole machine is reduced, and the problem that vibration of the reciprocating saw is large is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of power tools, in particular to a reciprocating saw. Background Art

[0002] A power saw with a reciprocating saw blade is also simply called a reciprocating saw. During the working process of the reciprocating saw, the saw blade is continuously accelerated and decelerated to perform a reciprocating motion, which inevitably causes the reciprocating saw to generate a large vibration. This vibration not only increases the noise but also makes the operator uncomfortable. For this reason, the reciprocating saw has been continuously improved to reduce the vibration of the whole machine.

[0003] CN202090000326.3 discloses a reciprocating saw, including a motor and a double eccentric anti-rotation yoke mechanism connected to the motor. The motor includes a front end and a rear end. The front end includes a front surface defining a first vertical plane, and the rear end includes a rear surface defining a second vertical plane parallel to the first vertical plane. The double eccentric anti-rotation yoke mechanism includes a main shaft driven to reciprocate relative to the motor along a main shaft axis parallel to the motor axis. The main shaft includes a rear end closest to the motor and a counterweight driven to reciprocate relative to the motor. The main shaft is arranged above the motor. When the main shaft reciprocates forward and backward in each driving cycle, the rear end of the main shaft extends into the space defined between the first and second vertical planes.

[0004] However, in the above reciprocating saw, since the counterweight is placed on the lower side of the main shaft and between the main shaft and the large gear, this will cause the acceleration of the whole machine in the forward direction and the R rotation direction (where the R rotation direction is the direction in which the main shaft rotates along its own axis) to be large, resulting in large vibration of the machine. In addition, the structure of this reciprocating saw is relatively complex, with high process requirements, heavy weight of the whole machine, and high cost. Summary of the Utility Model

[0005] The purpose of the utility model is to at least solve the problem of large vibration existing in the existing reciprocating saw. This purpose is achieved through the following technical solutions:

[0006] The utility model provides a reciprocating saw, including:

[0007] A housing;

[0008] A motor, the motor is arranged inside the housing, and the motor has an output shaft extending along a first direction;

[0009] A transmission wheel, the transmission wheel is fixed inside the housing through a support shaft, the support shaft is extended along a second direction, and along the second direction, the transmission wheel has a first plane facing the output shaft, the transmission wheel is transmission-connected to the output shaft and rotates under the drive of the motor, the rotation axis of the transmission wheel is parallel to the second direction, and the second direction is perpendicular to the first direction;

[0010] A reciprocating assembly, the reciprocating assembly comprising a working shaft drivingly connected to the transmission wheel;

[0011] A counterweight assembly, the counterweight assembly comprising a counterweight transmission-connected to the transmission wheel;

[0012] The working shaft and the counterweight block both reciprocate along a first direction under the drive of the motor, and the movement direction of the working shaft is opposite to the movement direction of the counterweight block;

[0013] Along the second direction, the output shaft, the transmission wheel, the working shaft and the counterweight are arranged in sequence, and the center of gravity of the counterweight assembly and the center of gravity of the reciprocating assembly are both located on the side of the first plane away from the output shaft.

[0014] The reciprocating saw described in the utility model includes a housing, a motor, a transmission wheel, a reciprocating assembly and a counterweight assembly. By arranging the working shaft and the counterweight on one side of the transmission wheel, and making the center of gravity of the reciprocating assembly and the center of gravity of the counterweight assembly both on the same side of the first plane of the transmission wheel, and at the same time, by limiting the movement direction of the working shaft to be opposite to the movement direction of the counterweight, it helps to reduce the acceleration of the reciprocating saw in the first direction and the R rotation direction, thereby helping to reduce the overall theoretical acceleration and reduce the vibration effect of the whole machine, thereby effectively solving the problem of large vibration in existing reciprocating saws. In addition, the structure of the reciprocating saw is relatively simple, which helps to reduce the overall weight of the reciprocating saw, thereby helping to reduce the manufacturing and processing costs of the reciprocating saw and improve the mass production qualification rate of the reciprocating saw.

[0015] In addition, the reciprocating saw according to the utility model may also have the following additional technical features:

[0016] In some embodiments of the utility model, the transmission wheel has a first eccentric portion and a second eccentric portion, the first eccentric portion is transmission-connected to the working shaft, the second eccentric portion is transmission-connected to the counterweight block, and the first eccentric portion and the second eccentric portion are respectively arranged on opposite sides of the transmission wheel along the second direction.

[0017] In some embodiments of the present utility model, the counterweight assembly further includes:

[0018] ​A fixed block, which is detachably arranged on the counterweight block and cooperates with the counterweight block to form an avoidance space for the working shaft to penetrate through;

[0019] A push plate, which is detachably arranged on the second eccentric part, and an insertion part is arranged on the push plate, and the insertion part is accommodated in the limit groove of the fixed block.

[0020] In some embodiments of the present invention, along the second direction, the distance between the center of gravity of the counterweight block assembly and the first plane is less than or equal to 2 times the distance between the center of gravity of the reciprocating assembly and the first plane.

[0021] In some embodiments of the present invention, the center of gravity of the counterweight block assembly and the center of gravity of the reciprocating assembly are both located on a straight line parallel to the axis of the working shaft.

[0022] In some embodiments of the present invention, two spaced clamping plates are arranged on the working shaft; the first eccentric part is detachably arranged on the transmission wheel, and one end of the first eccentric part is accommodated between the two clamping plates.

[0023] In some embodiments of the present invention, the distance between the axis of the first eccentric part and the rotation axis of the transmission wheel is 16 mm; the distance between the axis of the second eccentric part and the rotation axis of the transmission wheel is 10 mm.

[0024] In some embodiments of the present invention, it further includes:

[0025] A first limiting part, which is fixedly arranged inside the housing;

[0026] A second limiting part, the first limiting part and the second limiting part are arranged at intervals along the first direction,

[0027] A connecting rod, the two ends of the connecting rod are respectively connected and arranged on the first limiting part and the second limiting part, and the counterweight block is movably arranged on the connecting rod.

[0028] In some embodiments of the present invention, the transmission wheel is arranged at one end of the support shaft; the reciprocating saw further includes:

[0029] A first gear, which is arranged on the output shaft and is a first bevel gear;

[0030] A second gear, which is sleeved on the support shaft and is a second bevel gear, the second gear is in transmission connection with the first gear, and along the second direction, the second gear and the transmission wheel are respectively arranged on both sides of the first gear.

[0031] In some embodiments of the present utility model, a first bearing and a second bearing are sleeved on the transmission shaft, and the second gear is arranged between the first bearing and the second bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered as a limitation of the present utility model. Moreover, throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0033] Figure 1 is a schematic structural diagram of a reciprocating saw according to an embodiment of the present utility model;

[0034] Figure 2 is a partial structural schematic diagram inside the housing according to an embodiment of the present utility model;

[0035] Figure 3 is a schematic structural diagram of the transmission part of a reciprocating saw according to an embodiment of the present utility model;

[0036] Figure 4 is a sectional schematic diagram of the transmission part of a reciprocating saw according to an embodiment of the present utility model;

[0037] Figure 5 is a partial structural schematic diagram of a reciprocating saw according to an embodiment of the present utility model;

[0038] Figure 6 is a partial structural exploded schematic diagram of a reciprocating saw according to an embodiment of the present utility model;

[0039] Figure 7 is a schematic structural diagram of a transmission wheel according to an embodiment of the present utility model;

[0040] Figure 8 is a schematic structural diagram of a transmission wheel from a certain perspective according to an embodiment of the present utility model;

[0041] Figure 9 is a schematic structural diagram of a reciprocating assembly according to an embodiment of the present utility model;

[0042] Figure 10 is a schematic structural diagram of a counterweight assembly according to an embodiment of the present utility model;

[0043] Figure 11 is a schematic diagram of the force analysis of a reciprocating saw during operation according to an embodiment of the present utility model.

[0044] The reference numerals in the drawings are represented as follows:

[0045] 100, reciprocating saw;

[0046] 1. Housing

[0047] 21. First fixing bracket; 22. Second fixing bracket

[0048] 3. Motor

[0049] 4. Transmission mechanism; 41. Mounting bracket; 42. First gear; 43. Second gear; 44. Support shaft; 45. First bearing; 46. Second bearing

[0050] 5. Reciprocating assembly; 51. Working shaft; 511. Clamping plate; 52. Saw blade

[0051] 6. Counterweight assembly; 61. Counterweight; 611. Guide groove; 612. Avoidance groove; 62. Fixed block; 621. Limit groove; 63. First screw connector; 64. Pusher plate; 65. Insertion part

[0052] 7. Transmission wheel; 701. First connection hole; 702. Second connection hole; 703. Third connection hole; 704. First plane

[0053] 71. First eccentric part; 72. Second eccentric part; 721. Annular column; 722. Fixed plate; 723. Second screw connector

[0054] 8. Connector

[0055] 91. First limiting part; 92. Second limiting part; 93. Connecting rod Detailed implementation manner

[0056] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be completely conveyed to those skilled in the art.

[0057] It should be understood that the terms used herein are for the purpose of describing particular example embodiments only and are not intended to be limiting. Unless the context clearly dictates otherwise, the singular forms "a", "an", and "the" as used herein may also include the plural forms. The terms "comprising", "including", "containing", and "having" are inclusive and thus specify the presence of the stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order described or illustrated, unless explicitly indicated as an order of performance. It should also be understood that additional or alternative steps may be used.

[0058] Although the terms first, second, third, etc. may be used herein to describe multiple elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or section from another. Unless the context clearly indicates otherwise, terms such as "first", "second", and other numerical terms when used herein do not imply an order or sequence. Thus, a first element, component, region, layer, or section discussed below may be referred to as a second element, component, region, layer, or section without departing from the teachings of the example embodiments.

[0059] For ease of description, spatial relative relationship terms may be used herein to describe the relationship of one element or feature shown in the figures to another element or feature, such as "inside", "outside", "inner side", "outer side", "below", "beneath", "above", "over", etc. Such spatial relative relationship terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is flipped, an element described as "below" or "beneath" another element or feature will then be oriented "above" or "over" the other element or feature. Thus, the example term "below" can include both an upper and a lower orientation.

[0060] A power saw with a reciprocating saw blade is also simply referred to as a reciprocating saw. During the working process of a reciprocating saw, the saw blade is continuously accelerated and decelerated to perform reciprocating motion, which inevitably causes the reciprocating saw to generate relatively large vibrations. Such vibrations not only increase the noise but also make the operator uncomfortable. For this reason, reciprocating saws have been continuously improved to reduce the vibrations of the whole machine.

[0061] An existing reciprocating saw includes a motor, and a double eccentric scotch yoke mechanism coupled to the motor. The motor includes a front end and a rear end, the front end including a front face defining a first vertical plane, and the rear end including a rear face defining a second vertical plane parallel to the first vertical plane. The double eccentric scotch yoke mechanism includes a spindle driven to reciprocate relative to the motor along a spindle axis parallel to the motor axis, the spindle including a rear end closest to the motor, and a counterweight driven to reciprocate relative to the motor. The spindle is arranged above the motor. When the spindle reciprocates forward and backward in each drive cycle, the rear end of the spindle extends into the space defined between the first and second vertical planes.

[0062] However, the reciprocating saw has a counterweight placed on the lower side of the main shaft and between the main shaft and the large gear, which will cause the whole machine to have large acceleration in the forward direction and in the R rotation direction, thereby causing the machine to vibrate greatly, wherein the R rotation direction is the direction in which the main shaft rotates along itself. In addition, the reciprocating saw has a complex structure, high process requirements, heavy machine weight, and high cost.

[0063] In order to solve the above problems, the present application proposes a reciprocating saw, which specifically includes a housing 1, a transmission wheel 7, a reciprocating assembly 5 and a counterweight assembly 6. Among them, the motor 3 is arranged inside the housing 1, and the motor 3 has an output shaft extending along the first direction a. The transmission wheel 7 is fixed inside the housing 1 through a support shaft 44, and the support shaft 44 is extended along the second direction b. In the second direction b, the transmission wheel 7 has a first plane 704 facing the output shaft. The transmission wheel 7 is connected to the output shaft by transmission and rotates under the drive of the motor 3. The rotation axis of the transmission wheel 7 is parallel to the second direction b, and the second direction b is perpendicular to the first direction a. The reciprocating assembly 5 includes a working shaft 51 connected to the transmission wheel 7 by transmission. The counterweight assembly 6 includes a counterweight 61 connected to the transmission wheel 7 by transmission. The working shaft 51 and the counterweight 61 both reciprocate along the first direction a under the drive of the motor 3, and the movement direction of the working shaft 51 is opposite to the movement direction of the counterweight 61. Along the second direction, the output shaft, the transmission wheel 7, the working shaft 51 and the counterweight 61 are arranged in sequence, and the center of gravity of the counterweight assembly and the center of gravity of the reciprocating assembly are both located on the side of the first plane away from the output shaft.

[0064] The reciprocating saw described in the present application has the working shaft 51 and the counterweight 61 arranged on one side of the transmission wheel 7, and the centers of gravity of the reciprocating assembly 5 and the counterweight assembly 6 are both located on the same side of the transmission wheel 7. At the same time, by defining that the moving direction of the working shaft 51 is opposite to the moving direction of the counterweight 61, it helps to reduce the acceleration of the reciprocating saw in the first direction and the R rotation direction, thereby helping to reduce the overall theoretical acceleration and the vibration effect of the whole machine, and further effectively solving the problem of large vibration existing in the existing reciprocating saw. At the same time, the structure of the reciprocating saw is relatively simple, which helps to reduce the overall weight of the reciprocating saw, and further helps to reduce the manufacturing and processing costs of the reciprocating saw and improve the mass production qualification rate of the reciprocating saw.

[0065] Specifically, as Figure 1 and Figure 2 shown, the above-mentioned housing 1 forms an accommodating space and a holding part that can be held by the user. The holding part is used for the user to hold and move. The above-mentioned transmission wheel 7, motor 3, reciprocating assembly 5 and counterweight assembly 6 are all arranged inside the accommodating space. Among them, the motor 3 has an output shaft extending along the first direction a. In this embodiment, the first direction a is the horizontal forward direction. At the same time, the second direction b is the vertical upward direction, and along the second direction b, the output shaft of the motor 3, the transmission wheel 7, the working shaft 51 and the counterweight 61 are arranged in sequence.

[0066] At this time, a first fixing frame 21 and a second fixing frame 22 are fixedly arranged inside the housing 1. The first fixing frame 21 and the second fixing frame 22 cooperate to form a protection space for accommodating the above-mentioned reciprocating assembly 5 and counterweight assembly 6. Among them, the motor 3 and the transmission mechanism 4 are connected to the first fixing frame 21. The transmission mechanism 4 includes a mounting frame 41, a first gear 42, a second gear 43, a support shaft 44, a first bearing 45 and a second bearing 46. The mounting frame 41 and the first fixing frame 21 are fixed together by a connecting piece 8. Preferably, the connecting piece 8 is set as a screw or a bolt. At the same time, the first gear 42 is connected to the output shaft of the motor 3 and can rotate around the axis of the output shaft under the action of the motor 3. In this embodiment, the above-mentioned motor 3 is set as a brushless motor 3.

[0067] As Figures 1-4As shown, the above-mentioned first gear 42 is connected and arranged on the output shaft. At the same time, the support shaft 44 is accommodated on the mounting bracket 41, and along the second direction b, the first bearing 45, the second gear 43, and the second bearing 46 are sequentially sleeved on the support shaft 44. Among them, the second gear 43 is in transmission connection with the first gear 42. In this embodiment, both the first gear 42 and the second gear 43 are arranged as bevel gears. Using bevel gears for the first gear 42 and the second gear 43 can transfer the driving direction of the motor 3 from the first rotation plane to the second rotation plane. The first rotation plane is perpendicular to the first direction a, and the second rotation plane is perpendicular to the second direction b, that is, the first rotation plane is perpendicular to the second rotation plane. Preferably, the radial dimension of the first gear 42 is smaller, the radial dimension of the second gear 43 is larger, and the first rotation plane is a vertical plane, and the second rotation plane is a horizontal plane.

[0068] At this time, the first bearing 45 is arranged at the first end of the support shaft 44, the second gear 43 is fixedly arranged in the middle of the support shaft 44, and the above-mentioned transmission wheel 7 is fixedly arranged at the second end of the support shaft 44. Among them, the first bearing 45 and the second bearing 46 are used to keep the support shaft 44 rotatable. When the motor 3 is working normally, under the transmission of the first gear 42 and the second gear 43, the transmission wheel 7 can be rotated, and at this time, the rotation axis of the transmission wheel 7 is the axis of the support shaft 44. By arranging the second gear 43 between the first bearing 45 and the second bearing 46 and cooperating with the structure of the mounting bracket 41, the second gear 43 can be changed from the existing upper-side installation to the lower-side installation, and by limiting the second gear 43 to be placed between the first bearing 45 and the second bearing 46, the force balance of the transmission system can be effectively improved, and the lubrication system of the transmission mechanism 4 can be made independent.

[0069] As Figures 3-8 shown, the transmission wheel 7 has a first connection hole 701 penetrating the transmission wheel 7 along the second direction b. Among them, the transmission wheel 7 is fixed on the support shaft 44 through a connecting member 8 passing through the first connection hole 701. Preferably, the connecting member 8 is arranged as a screw or a bolt. At the same time, along the second direction b, the transmission wheel 7 has a first plane 704 facing the output shaft and a second plane facing away from the output shaft.

[0070] It should be understood that the conveying wheel 7 has a first eccentric portion 71 and a second eccentric portion 72. Along the second direction b, the first eccentric portion 71 and the second eccentric portion 72 are respectively arranged on opposite sides of the conveying wheel 7. Among them, the first eccentric portion 71 is in driving connection with the working shaft 51, and the second eccentric portion 72 is in driving connection with the counterweight 61. Driven by the motor 3 and the transmission mechanism 4, the conveying wheel 7 rotates, and can make the working shaft 51 and the counterweight 61 reciprocate along the first direction a. Arranging the first eccentric portion 71 and the second eccentric portion 72 on opposite sides of the fixed block 62 respectively can avoid the interference of the movements of the working shaft 51 and the counterweight 61. In this embodiment, the axes of the first eccentric portion 71, the rotation axis of the conveying wheel 7, and the axis of the second eccentric portion 72 are all in the same plane, and the axes of the first eccentric portion 71 and the second eccentric portion 72 are respectively arranged on opposite sides of the rotation axis of the conveying wheel 7, so that the movement directions of the working shaft 51 and the counterweight 61 are opposite. Compared with the existing double swing rod bearing mechanism, the present application adopts the cooperation form of the conveying wheel 7 and the above-mentioned transmission mechanism 4 to ensure the reciprocating movement of the working shaft 51 and the counterweight 61. The overall structure is simple, and the processing and assembly processes can be effectively simplified, which can further reduce the installation cost of the reciprocating saw and help improve the qualification rate of mass production.

[0071] In this embodiment, the first eccentric portion 71 is detachably arranged on the conveying wheel 7. At the same time, two spaced clamping plates 511 are arranged on the working shaft 51, and one end of the first eccentric portion 71 is received between the two clamping plates 511. As shown in Figure 4 , Figure 7 and Figure 8 shown, the conveying wheel 7 also has a second connection hole 702 penetrating the conveying wheel 7 along the second direction b. One end of the first eccentric portion 71 is inserted into the second connection hole 702 and is located on the side away from the second gear 43, and the other end of the first eccentric portion 71 is inserted and received between the two clamping plates 511 of the working shaft 51. Adopting the insertion method to arrange the first eccentric portion 71 on the conveying wheel 7 can effectively reduce the assembly difficulty of the reciprocating saw. In this embodiment, the first eccentric portion 71 includes a first pin shaft and a first sleeve sleeved on the first pin shaft.

[0072] Here, it should be noted that the reciprocating assembly 5 includes the above-mentioned working shaft 51 and the saw blade 52. Among them, the saw blade 52 is arranged at one end of the working shaft 51, and the two clamping plates 511 are closely arranged in the middle of the working shaft 51. Preferably, the two clamping plates 511 are spaced along the first direction a, and a clamping space for inserting the first eccentric portion 71 is formed between the two clamping plates 511. As a preferably implementable manner, the two clamping plates 511 and the working shaft 51 are integrally formed.

[0073] As shown in Figure 4and Figure 7 As shown in the figure, a second eccentric part 72 is provided on one side of the transmission wheel 7 close to the second gear 43. The second eccentric part 72 includes an annular column 721 protruding from the first plane 704, and a fixing plate 722 fixedly arranged on the annular column 721. The fixing plate 722 and the annular column 721 cooperate to clamp the push plate 64 of the following counterweight assembly 6, so as to realize the connection between the second eccentric part 72 and the counterweight assembly 6. In this embodiment, a third connection hole 703 is provided on the annular column 721. By providing a second screw member 723 passing through the fixing plate 722 and screwed on the third connection hole 703, the fixing plate 722 can be installed on the annular column 721. At this time, the push plate 64 of the following counterweight assembly 6 is clamped between the fixing plate 722 and the annular column 72. It should be noted that the rotation axis of the transmission wheel 7 is located inside the annular column 721. At this time, both the fixing plate 722 and the push plate 64 are provided with avoidance holes for the support shaft 44 to pass through. At the same time, the first pin shaft of the above-mentioned first eccentric part 71 passes through the second connection hole 702 and abuts against the push plate 64.

[0074] It should be understood that the counterweight assembly 6 includes the above-mentioned counterweight 61, fixed block 62 and push plate 64. Among them, the push plate 64 is detachably arranged on the second eccentric part 72, and an insertion part 65 is arranged on the push plate 64, and the insertion part 65 is accommodated in the limit groove 621 of the fixed block 62. Specifically, as Figure 6 and Figure 10 shown, the push plate 64 includes a fixing part clamped on the second eccentric part 72, and a pushing part extending along the first direction a. An avoidance hole is provided on the fixing part. At this time, the avoidance hole is sleeved outside the annular column 721, which helps to ensure that the annular column 721 acts on the push plate when rotating with the transmission wheel 7. At the same time, an insertion part 65 is provided at one end of the pushing part away from the fixing part, and the insertion part 65 is hinged to the fixed block 62 to ensure that the push plate 64 can act on the counterweight 61 and make it reciprocate along the first direction a. In this embodiment, the structure of the insertion part 65 is the same as that of the first eccentric part 71, and will not be elaborated here.

[0075] At this time, along the second direction a, the push plate 64, the fixed block 62, and the counterweight 61 are sequentially connected and arranged. At this time, the working shaft 51 is movably inserted between the fixed block 62 and the counterweight 61. In this embodiment, a limiting groove 621 for accommodating the insertion part 65 is formed at one end of the fixed block 62, and the other end of the fixed block 62 is detachably connected to the counterweight 61. Specifically, the counterweight 61 and the fixed block 62 are connected by a first screw member 63. As a preferably implementable embodiment, an avoidance groove 612 is formed on the counterweight 61. When the fixed block 62 is fixedly connected to the counterweight 61, the fixed block 62 can block the avoidance groove 612 and cooperate with the counterweight 61 to form an avoidance space for the working shaft 51 to penetrate. Such a setting can shorten the distance between the center of gravity of the counterweight assembly 6 and the center of gravity of the reciprocating assembly 5. At the same time, it can also effectively reduce the influence of the counterweight assembly 6 on the movement of the working shaft 51, thereby ensuring the use effect of the reciprocating saw.

[0076] Still as Figure 2 and Figure 3 shown, the counterweight 61 and the working shaft 51 reciprocate under the drive of the motor 3. To ensure the accuracy of the movement, the reciprocating saw further includes a limiting mechanism, which is accommodated on the second fixing frame 22 and plays a guiding role for the working shaft 51 and the counterweight 61. Specifically, the limiting mechanism includes a first limiting part 91, a second limiting part 92, and a connecting rod 93. Wherein, both ends of the connecting rod 93 are respectively connected to the first limiting part 91 and the second limiting part 92, so that the limiting mechanism forms a limiting main body and can be accommodated inside the second mounting frame 41. In this embodiment, the first limiting part 91 and / or the second limiting part 92 are fixedly arranged on the second mounting frame 41. Along the first direction a, the first limiting part 91 and the second limiting part 92 are arranged at intervals. Working holes for the working shaft 51 to penetrate are provided on both the first limiting part 91 and the second limiting part 92. At the same time, the number of the connecting rods 93 is two and they are respectively arranged on both sides of the working shaft 51.

[0077] Here, it should be noted that the above-mentioned counterweight 61 is movably arranged on the connecting rod 93. As Figure 10 shown, a guiding groove 611 and an avoidance groove 612 are formed on the side surface of the counterweight 61 facing the fixed block 62. Wherein, the guiding groove 611 is used to accommodate the two connecting rods 93, and the avoidance groove 612 is used to accommodate the working shaft 51. When the motor 3 works, under the action of the transmission mechanism 4 and the transmission wheel 7, the working shaft 51 and the matching block move. Among them, the counterweight 61 reciprocates along the first direction a under the limitation of the guiding groove 611, and the working shaft 51 reciprocates along the first direction a under the limitation of the first limiting part 91 and the second limiting part 92.

[0078] In this embodiment, the axis of the first eccentric part 71, the axis of rotation of the transmission wheel 7, and the axis of the second eccentric part 72 are located in the same plane. At this time, the movement direction of the working shaft 51 is opposite to the movement direction of the counterweight 61. Preferably, as Figure 8 shown, the distance R1 between the axis of the first eccentric part 71 and the axis of rotation of the transmission wheel 7 is 16 mm; the distance R2 between the axis of the second eccentric part 72 and the axis of rotation of the transmission wheel 7 is 10 mm. By defining the distances between the axis of the first eccentric part 71, the axis of rotation of the transmission wheel 7, and the axis of the second eccentric part 72, it helps to further reduce the acceleration of the working shaft 51 in the first direction a, and thus the vibration effect of the reciprocating saw can be minimized.

[0079] At this time, the center of gravity O of the counterweight assembly 6 2 and the center of gravity O of the reciprocating assembly 5 1 are both located on the side of the first plane 704 away from the output shaft. Such a setting helps to reduce the acceleration of the working shaft 51 in the first direction a, and thus the vibration effect of the reciprocating saw can be effectively reduced. Preferably, along the second direction b, the distance between the center of gravity O of the counterweight assembly 6 2 and the first plane 704 is less than or equal to twice the distance between the center of gravity O of the reciprocating assembly 5 1 and the first plane 704. As Figure 11 shown, in this embodiment, along the second direction b, the first plane 704 and the second straight line x2 are in the same plane. At this time, the distance between the center of gravity O of the reciprocating assembly 5 1 and the first plane 704 is d1, and the distance between the center of gravity O of the counterweight assembly 6 2 and the first plane 704 is d2, and d2 ≤ 2d1. By defining the distance d2 between the center of gravity O of the counterweight assembly 6 2 and the first plane 704, the vibration effect of the whole machine can be effectively reduced.

[0080] It should be further understood that the center of gravity O of the counterweight assembly 6 2 and the center of gravity O of the reciprocating assembly 5 1 are both located on a straight line parallel to the axis of the working shaft 51. As Figure 11 shown, along the second direction b, the center of gravity O of the whole machine is located on the first straight line x1, and the center of gravity O of the counterweight assembly 6 2 and the center of gravity O of the reciprocating assembly 5 1 are both located on the third straight line x3. Such a setting can make the reciprocating saw achieve the optimal balance effect, which helps to further reduce the acceleration of the working shaft 51 in the first direction a, and thus the vibration effect of the reciprocating saw can be minimized.

[0081] Here, it should be noted that the calculation formula for the acceleration of the whole machine is as follows: a = a1 2 +a 2 2 -2*a 1 *a 2 *cosθ

[0082] During the movement of the reciprocating component 5, the imbalance of the maximum inertia force will cause the translational motion of the whole machine. At this time, the translational acceleration is a 1 , and its specific calculation formula is as follows:

[0083] a 1 = F0 / m0 = (F2 - F1) / m0, where m0 is the mass of the whole machine;

[0084] As Figure 11 shown, due to the moment imbalance of the maximum inertia force caused by the reciprocating component 5 and the counterweight component 6 at the center of gravity, the imbalance moment causes the entire reciprocating component 5 to rotate around its center of gravity O 1 at a certain acceleration. The calculation of the circular motion acceleration is as follows: a 2 = M0*La / I0 = La*(F 2 *L2 - F 1 *L1) / I0, where M0 is the total torque. La is the distance between the center of gravity O and the vibration measuring point, L1 is the distance between the center of gravity O 1 of the reciprocating component 5 and the center of gravity O of the whole machine, L2 is the distance between the center of gravity O 2 of the counterweight component 6 and the center of gravity O of the whole machine, and I0 is the moment of inertia of the whole machine.

[0085] In this embodiment, since F 1 = m 1 *ω 2 *R 1 , F 2 = m 2 *ω 2 *R 2 , assuming F 1 = F 2 , that is, m 1 *ω 2 *R 1 = m 2 *ω 2 *R 2 , the total mass m 2 of the counterweight component 6 is obtained as 313.5 grams, and a 1 = (F2 - F1) / m0 = 0. m 1 = 197.5 grams, m 2 = 313.5 grams. At the same time, the eccentric radius R2 of the counterweight component 6 is 10, and the eccentric radius R1 of the reciprocating component 5 is 16.

[0086] Combined Figure 11 As shown, since the center of gravity O of the counterweight assembly 6 is moved upward in this application 2 to make L1 and L2 equal, so a2 = La*(F2*L2 - F1*L1) / I0 = 0.

[0087] Since a1 = 0 and a2 = 0, the theoretical value of the acceleration of the whole machine a = a1 2 + a2 2 - 2*a1*a2*cosθ = 0.

[0088] In this application, the center of gravity O of the reciprocating assembly 5 1 and the center of gravity O of the counterweight assembly 6 2 are both on the upper side of the conveyor wheel 7, and the two are located on the second straight line x2, so that the acceleration of the whole machine in the first direction a and the R rotation direction can both reach the minimum value of zero, thus making the theoretical acceleration of the whole machine zero, greatly reducing the vibration of the whole machine, and the overall structure and process are relatively simple, greatly reducing the cost and improving the qualification rate of mass production.

[0089] The above is only the preferred specific implementation manner of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present utility model should be covered by the protection scope of the present utility model. Therefore, the protection scope of the present utility model should be subject to the protection scope of the claims.

Claims

1. A reciprocating saw, characterized in that: include: case; A motor, the motor is arranged inside the housing, and the motor has an output shaft extending along a first direction; A transmission wheel, wherein the transmission wheel is fixed inside the housing through a support shaft, the support shaft is extended along a second direction, and along the second direction, the transmission wheel has a first plane facing the output shaft, the transmission wheel is transmission-connected to the output shaft and rotates under the drive of the motor, and the rotation axis of the transmission wheel is parallel to the second direction, and the second direction is perpendicular to the first direction; A reciprocating assembly, the reciprocating assembly comprising a working shaft drivingly connected to the transmission wheel; A counterweight assembly, the counterweight assembly comprising a counterweight drivingly connected to the transmission wheel; The working shaft and the counterweight block both reciprocate along a first direction under the drive of the motor, and the movement direction of the working shaft is opposite to the movement direction of the counterweight block; Along the second direction, the output shaft, the transmission wheel, the working shaft and the counterweight are arranged in sequence, and the center of gravity of the counterweight assembly and the center of gravity of the reciprocating assembly are both located on the side of the first plane away from the output shaft.

2. The reciprocating saw according to claim 1, characterized in that: The transmission wheel has a first eccentric portion and a second eccentric portion, the first eccentric portion is transmission-connected to the working shaft, the second eccentric portion is transmission-connected to the counterweight block, and the first eccentric portion and the second eccentric portion are respectively arranged on opposite sides of the transmission wheel along the second direction.

3. The reciprocating saw according to claim 2, characterized in that: The counterweight assembly also includes: A fixed block, which is detachably arranged on the counterweight block and cooperates with the counterweight block to form an escape space for the working shaft to pass through; A push plate is detachably arranged on the second eccentric portion, and an inserting portion is arranged on the push plate, and the inserting portion is accommodated in the limiting groove of the fixing block.

4. The reciprocating saw according to claim 3, characterized in that: Along the second direction, the distance between the center of gravity of the counterweight assembly and the first plane is less than or equal to twice the distance between the center of gravity of the reciprocating assembly and the first plane.

5. The reciprocating saw according to claim 4, characterized in that: The center of gravity of the counterweight assembly and the center of gravity of the reciprocating assembly are both located on a straight line parallel to the axis of the working shaft.

6. The reciprocating saw according to claim 2, characterized in that: The working shaft is provided with two clamping plates which are arranged at intervals; the first eccentric portion is detachably arranged on the transmission wheel, and one end of the first eccentric portion is accommodated between the two clamping plates.

7. The reciprocating saw according to claim 6, characterized in that The distance between the axis of the first eccentric portion and the rotation axis of the transmission wheel is 16 mm; the distance between the axis of the second eccentric portion and the rotation axis of the transmission wheel is 10 mm.

8. The reciprocating saw according to claim 2, characterized in that: Also includes: a first limiting portion, wherein the first limiting portion is fixedly disposed inside the housing; a second limiting portion, wherein the first limiting portion and the second limiting portion are spaced apart from each other along the first direction; A connecting rod, two ends of which are respectively connected to the first limiting portion and the second limiting portion, and the counterweight block is movably arranged on the connecting rod.

9. The reciprocating saw according to any one of claims 1 to 8, characterized in that: The transmission wheel is arranged at one end of the support shaft; the reciprocating saw further comprises: A first gear, which is disposed on the output shaft and is a first bevel gear; The second gear is sleeved on the supporting shaft and is a second bevel gear. The second gear is transmission-connected with the first gear. Along the second direction, the second gear and the transmission wheel are respectively arranged on both sides of the first gear.

10. The reciprocating saw according to claim 9, characterized in that The support shaft is sleeved with a first bearing and a second bearing, and the second gear is arranged between the first bearing and the second bearing.

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