CN102950332A

CN102950332A - Portable cutting machine

Info

Publication number: CN102950332A
Application number: CN2011102408257A
Authority: CN
Inventors: 孙益民; 张士松
Original assignee: Positec Power Tools Suzhou Co Ltd
Current assignee: Positec Power Tools Suzhou Co Ltd
Priority date: 2011-08-18
Filing date: 2011-08-18
Publication date: 2013-03-06
Anticipated expiration: 2031-08-18
Also published as: CN102950332B

Abstract

The invention provides a portable cutting machine which comprises a shell, a swing output shaft, a motor, a driving shaft and a movement conversion mechanism. The swing output shaft partially extends out of the shell and is provided with an output shaft axis, the motor is accommodated in the shell, the driving shaft is driven to rotate by the motor and is provided with a driving shaft axis, the movement conversion mechanism converts rotation of the driving shaft into swing of the swing output shaft, and the output shaft axis is parallel to the driving shaft axis. According to the technical scheme, the portable cutting machine has the advantages that vibration of the portable cutting machine can be low during cutting operation, and the cutting precision and the operation comfort are improved.

Description

Portable cutting machine

Technical Field

The invention relates to a portable cutting machine, in particular to a portable cutting machine for swinging and cutting a workpiece.

Background

The existing portable cutting machine for cutting a workpiece by driving a saw blade to swing is internally provided with a motor, an eccentric part driven by the motor, a shifting fork matched with the eccentric part to convert rotation into swing, a swing output shaft driven by the shifting fork, and the saw blade arranged on the swing output shaft.

Because among the prior art, the axis of motor shaft and the axis homogeneous phase of swing output shaft set up perpendicularly, so lead to eccentric part and shift fork cooperation in-process produced frictional force and the axis of swing output shaft to be parallel, this moment under the effect of frictional force swing output shaft can produce certain displacement along its self axis direction, from this along with portable cutting machine cuts the work piece, make portable cutting machine load grow, frictional force also strengthens thereupon this moment, the vibrations that produce along the axis direction by swing output shaft this moment are very violent, lead to the cutting precision poor, and whole organism vibrations are too, the user uses very uncomfortable, when using for a long time, bring very big harm for user's health.

Disclosure of Invention

The invention provides a portable cutting machine, and particularly provides a portable cutting machine with a good damping effect.

In order to achieve the purpose, the technical scheme of the invention is as follows: a portable cutter comprising: a housing; a swing output shaft partially extending out of the housing, having an output shaft axis; a motor housed in the housing; a drive shaft driven for rotation by the motor, the drive shaft having a drive shaft axis; a motion conversion mechanism that converts rotation of the drive shaft into swing of the swing output shaft; the axis of the output shaft and the axis of the driving shaft are arranged in parallel.

Preferably, the motion converting mechanism includes an eccentric member mounted on the driving shaft, and a shift fork fitted with the eccentric member and fixedly mounted on the swing output shaft, the eccentric member having a center line eccentrically disposed with respect to the driving shaft axis, the center line being disposed in parallel with the output shaft axis.

Preferably, the oscillation frequency of the oscillating output shaft is greater than 30000 times/min.

Preferably, the housing includes a motor accommodating portion for accommodating the motor, and a holding portion for holding, and the holding portion is disposed separately from the accommodating portion.

Preferably, the overall longitudinal extension of the grip portion forms a longitudinal extension direction of the grip portion, and the longitudinal extension direction of the grip portion is perpendicular to the axis of the drive shaft.

Preferably, the output shaft axis is perpendicular to the longitudinal extension direction of the grip portion.

Preferably, the housing is further provided with a battery pack accommodating portion extending in the same direction as the grip portion.

Compared with the prior art, the axis of the driving shaft and the axis of the swinging output shaft are arranged in parallel, so that the friction force generated by the motion conversion mechanism can be perpendicular to the axis of the swinging output shaft, and the swinging output shaft can not generate displacement along the axis direction, therefore, when the portable cutting machine performs cutting operation, the swinging output shaft can not generate vibration along the axis direction of the swinging output shaft, so that the saw blade arranged on the swinging output shaft can perform cutting more accurately, and the portable cutting machine has very good operation comfort.

Drawings

The invention is further described with reference to the following figures and embodiments.

Fig. 1 is a perspective view of a portable cutter according to a first embodiment of the present invention;

FIG. 2 is a schematic view of the portable cutting machine of FIG. 1;

FIG. 3 is a schematic view of the portable cutting machine of FIG. 1;

FIG. 4 is a schematic view of the portable cutting machine of FIG. 1;

FIG. 5 is a cross-sectional view of the portable cutter of FIG. 2 taken along line P-P;

FIG. 6 is a perspective view of the portable cutting machine of FIG. 1 with the left housing half removed;

FIG. 7 is a perspective view of the portable cutting machine of FIG. 6 after the support base has been further removed;

FIG. 8 is an exploded perspective view of the motor and drive shaft of the portable cutting machine of FIG. 1;

FIG. 9 is an exploded perspective view of the swing output shaft of the portable cutting machine of FIG. 1;

fig. 10 is a perspective view of the portable cutting machine of fig. 6 after the motor, the support base and the swing output shaft are assembled;

FIG. 11 is a side elevational view of the support base of the portable cutting machine of FIG. 10 with the tool drive shaft and fork mounted thereon for mating with the motor;

FIG. 12 is a bottom view of the support base of FIG. 11;

FIG. 13 is a partially exploded perspective view of the motor, the support base and the drive shaft of FIG. 10;

FIG. 14 is a schematic view of a saw blade of the portable cutting machine of FIG. 1;

FIG. 15 is an exploded perspective view of a support assembly of the portable cutting machine of FIG. 1;

fig. 16 is a perspective view of a support assembly of the portable cutter of fig. 1;

FIG. 17 is a schematic view of the portable cutting machine of FIG. 1 mounted with a fan blade;

FIG. 18 is a partial cross-sectional view of the portable cutter of FIG. 3 with the motor housing partially broken away to reveal the air duct inlet;

FIG. 19 is a cross-sectional view of the portable cutter of FIG. 2 taken along line I-I;

fig. 20 is a schematic view of a saw blade of a portable cutting machine according to a second embodiment of the present invention;

fig. 21 is a schematic view of a saw blade of a portable cutting machine according to a third embodiment of the present invention;

fig. 22 is a schematic view of a saw blade of a portable cutting machine according to a fourth embodiment of the present invention;

FIG. 23 is a partial schematic view of the saw blade of FIG. 22 with the teeth extending in a direction opposite to the direction in which the base extends;

fig. 24 is a side view of a portable cutter according to a fifth embodiment of the present invention;

FIG. 25 is a partially exploded schematic view of the portable cutter of FIG. 24;

FIG. 26 is a perspective view of a connector of the support assembly of FIG. 25;

FIG. 27 is a perspective view of the bottom plate of the support assembly of FIG. 25;

FIG. 28 is a schematic view of a support assembly according to a sixth embodiment of the present invention;

FIG. 29 is a schematic view of the support assembly of FIG. 28;

FIG. 30 is a partially exploded view of the support assembly of FIG. 29;

FIG. 31 is a schematic view of a support assembly according to a seventh embodiment of the present invention;

fig. 32 is a schematic view of the support assembly of fig. 31.

Wherein,

10. portable cutter 32, switch assembly 49 and accommodating part

12. Housing 33, guide assembly 50, shaft hole

14. Motor 34, trigger 51, mating part

15. Battery pack 35, left half shell 52 spline

16. Swing output shaft 36, control element 53, screw

18. Transmission mechanism 37, right half shell 54, eccentric shaft

19. End wall 38, motor shaft 55, fixing part

20. Saw blade 40, motor fan 56, eccentric bearing

21. Support assembly 42, power cord 58, drive section

22. Motor housing 44, drive shaft 60, mounting section

23. Air inlet 45, first support bearing 62, first drive arm

24. Transmission mechanism receiving portion 46, eccentric member 64, first driving surface

26. Battery pack receiving portion 47, drive shaft support 70, tool mounting end

28. Holding part 48, shifting fork 72, second support bearing

74. Third support bearing 126, air duct inlet 182, connector

76. Fastener 128, through hole 184 and bottom plate

77. Washer 130, saw blade 186, first housing

78. Supporting seat 132, mounting hole 188, second shell

80. First receiving cavity 134, connecting part 190, circular hole

82. Second receiving cavity 136, second side wall 192, annular steel ring

83. Screw hole 138, base 193, screw hole

84. Opening 139, serration 194, adapter

86. First opening 140, blade 196, abutment plate

87. Screw hole 142, mounting hole 198 and guide assembly

88. Second opening 144, connecting portion 200, through hole

89. Chock 146, second side wall 202, bottom plate screw hole

90. Connecting part 148, base part 204 and screw

92. Base 150, mounting hole 206, fixing plate

94. Mounting hole 152, saw blade 208, roller

96. First side 154, mounting hole 210, fixing plate slot

98. Surface 156, connection 212, support assembly

100. Serration 158, second sidewall 214, connector

102. Base plate 160, base 216, bottom plate

104. Connecting assembly 162, serration 218, mounting plate

106. Saw blade slot 164, first edge 220, abutment plate

108. Guide assembly 166, Portable cutter 222, guide assembly

112. Adjustment slot 168, housing 224, upper surface

114. Locking screw 170, swing output shaft 226, slotted

115. Nut 172, support assembly 228, and slot against plate

116. Support 174, fastener 230, support assembly

118. Assembly 175, washer 232, abutment plate

122. Connecting plate 176, saw blade 233, abutment

124. Air outlet 178, body shell 234, guide assembly

125. Baffle 180. head shell

Detailed Description

Referring to fig. 1, 5 and 6, a first embodiment of the present invention provides a portable cutting machine 10 including a housing 12, a motor 14 housed in the housing 12, a battery pack 15 for supplying power to the motor 14, a swing output shaft 16 driven by the motor 14, a transmission mechanism 18 disposed between the motor 14 and the swing output shaft 16, a saw blade 20 mounted on the swing output shaft 16 for cutting, and a support assembly 21 for supporting the portable cutting machine 10 against a surface of a workpiece (not shown) to be cut.

The housing 12 includes a motor housing portion 22 extending vertically, a transmission housing portion 24 connected to the motor housing portion 22 for housing the transmission 18, a battery pack housing portion 26 for housing the battery pack 15, and a grip portion 28 connected to the transmission housing portion 24 for gripping.

Referring to fig. 1, 3 and 4, the motor housing 22 is formed in a hollow cylindrical shape and extends lengthwise due to the overall lengthwise extension. Along its longitudinal extent, motor housing 22 is closed at one end to have an end wall 19 and at the other end is connected to a gear housing 24, and has a circumferential side wall that circumferentially surrounds motor 14. Air inlet openings 23 are provided in the end walls 19 to facilitate airflow for heat dissipation. Support bars (not shown) extending along the longitudinal extension direction of the motor accommodating portion are arranged on the circumferential side wall of the motor accommodating portion 22, and the number of the support bars is not less than three, and the support bars are arranged along the circumferential direction of the longitudinal extension direction of the motor accommodating portion, so that the motor 14 is stably supported in the motor accommodating portion 22.

The holding portion 28 and the motor accommodating portion 22 are separated from each other, so that the vibration when the user holds the holding portion 28 is relatively small, and the use comfort of the user is improved. The lengthwise extension of the grip part 28 forms the lengthwise extension direction of the grip part, and the lengthwise extension direction of the grip part is different from the lengthwise extension direction of the motor accommodating part, so that the length of the portable cutting machine 10 along the lengthwise extension direction of the grip part is reduced, the portable cutting machine 10 can be suitable for the working condition with relatively narrow space, and convenience is provided for the cutting work of a user in a small space. In the present embodiment, the longitudinal extension direction of the motor housing portion is perpendicular to the longitudinal extension direction of the grip portion, so that the length of the portable cutting machine 10 along the longitudinal extension direction of the grip portion is minimized, the overall structure is optimized, and the adaptability of the portable cutting machine 10 to a narrow space is optimized.

Referring to fig. 1 and 6, the battery pack receiving portion 26 is connected to the transmission mechanism receiving portion 24 and is disposed in parallel with the grip portion 28, i.e., extends along the longitudinal extension direction of the grip portion, and when the user uses the portable cutting machine 10 to perform cutting work, the battery pack receiving portion 26 is located at a side of the grip portion opposite to the user. The battery pack accommodating portion 26 is hollow and cylindrical, one end of the battery pack accommodating portion is connected to the transmission mechanism accommodating portion 24, and the other end of the battery pack accommodating portion is sealed, so that a relatively sealed accommodating space is formed in the battery pack accommodating portion 26, the battery pack 15 can be prevented from being polluted by dust generated during work or being damaged by impact, and the battery pack 15 can be effectively prevented from being lost.

In order to improve the stability of the portable cutting machine 10 in the cutting process, the surface of the battery pack accommodating portion 26 facing the workpiece can be abutted against the workpiece, so that a user can stably push the portable cutting machine 10 to perform cutting operation without maintaining the portable cutting machine 10 in a suspended state by force, thereby improving the cutting stability, saving the physical strength of the user and bringing great convenience to the user. In order to enhance the wear resistance of the surface, the surface may be provided with a wear resistant coating or be provided with other wear resistant elements such as metal blocks or the like.

A switch assembly 32 is also mounted on the housing 12 to control whether the portable cutter 10 is activated for operation. The switch assembly 32 includes a trigger 34 for user operation and a control element 36 connected to the battery pack 15 and the motor 14, the user operable control of the control element 36 via the trigger 34 to activate or deactivate the portable cutter 10. When the switch assembly 32 is assembled to the portable cutting machine 10, the whole is located between the grip portion 28 and the battery pack receiving portion 26 for the convenience of the user to operate, in the present embodiment, the switch assembly 32 is disposed on the grip portion 28, and the control element 36 is received inside the grip portion 28 to make the best use of the internal space of the grip portion 28, and the user can operate the portable cutting machine easily.

In order to facilitate the manufacturing of the housing 12, the housing 12 may be divided into a left half-housing 35 composed of a part of the transmission mechanism housing portion 24, a part of the grip portion 28 and a part of the battery pack housing portion 26, and a right half-housing 37 composed of the motor housing portion 22, a part of the transmission mechanism housing portion 24, a part of the grip portion 28 and a part of the battery pack housing portion 26 along the longitudinal extension direction of the grip portion. The left half shell 35 and the right half shell 37 are respectively made by integral molding, so that the shell 12 is easy to process and manufacture and convenient to assemble.

The battery pack 15 is accommodated in the battery pack accommodating portion 26, is composed of five battery cells, and has a rated voltage of 18V, so that the portable cutting machine 10 can satisfy the requirement of sufficient power and excellent portability. A power cord 42 is connected to the battery pack 15 for connection to an external power source for charging the battery pack 15.

Furthermore, the portable cutting machine 10 may not have the battery pack 15, and only the ac power supply is used for supplying power, so that the battery pack accommodating portion 26 is not required to be provided on the housing 12, thereby reducing the overall size. And moreover, the cost is saved.

Referring to fig. 2 and 5, the motor 14 is accommodated in the motor accommodating portion 22, and includes a stator, a rotor, a motor shaft 38 extending in the same direction as the longitudinal direction of the motor accommodating portion, and a motor fan 40 mounted on the motor shaft 38 for dissipating heat from the motor 14. Along the lengthwise extension direction of the motor containing part, the motor fan 40 is located between the rotor and the end wall of the motor containing part 22, and when the motor fan rotates, the motor fan can drive airflow to enter the motor containing part 22 from the air inlet hole 23 and blow towards the stator and the rotor to realize heat dissipation.

In the present embodiment, the motor 14 is a dc motor, and if the portable cutting machine 10 is configured to be powered by ac power, an ac motor may be used for the corresponding motor 14.

The rated rotating speed of the motor 14 is more than or equal to 20000 rpm, and the further rotating speed of the motor 14 is more than 30000 rpm, so that the portable cutting machine 10 has strong power and a longer service life.

Referring to fig. 1, 7 and 8, the transmission mechanism 18 is accommodated in the transmission mechanism accommodating portion 24, and includes a driving shaft 44, a first supporting bearing 45 sleeved on the driving shaft 44, a driving shaft supporting member 47 interference-fitted with the first supporting bearing 45 to support the driving shaft 44, an eccentric member 46 mounted on the driving shaft 44, and a shifting fork 48 engaged with the eccentric member 46. In the present embodiment, the eccentric member 46 and the shift fork 48 constitute a motion conversion mechanism for converting the rotation output from the motor 14 into the swing of the swing output shaft 16 to drive the saw blade 20 to perform the swing cutting.

The drive shaft 44 is disposed coaxially with the motor shaft 38 such that the drive shaft 44 extends in the same direction as the longitudinal direction of the motor housing. The drive shaft 44 is independent of the motor shaft 38 and is driven by the motor shaft 38, having a drive shaft axis O-O. The drive shaft 44 has a shaft bore 50 at one end for mating with the motor shaft 38 and an eccentric member 46 at the other end. The shaft hole 50 is a hexagon with central symmetry, and the motor shaft 14 and the shaft hole 50 are matched in a shape, so that the matching between the two is stable and the relative sliding cannot occur.

In order to reduce the vibration of the driving shaft 44 and the motor shaft 14, a spline 52 is disposed in the shaft hole 50, and a damping layer, which may be rubber, resin, or the like, is disposed on the outer surface of the spline 52.

Of course, the driving shaft 44 can be directly formed by the motor shaft 38, and the spline 52 is not needed, and the eccentric member 46 is installed on the motor shaft 38 to match with the shifting fork 48, so that the structure is simple, the manufacturing is easy, and the vibration in the transmission process is small.

The eccentric 46 has a centerline S-S that extends in a direction parallel to the drive shaft axis O-O, but is not collinear with the drive shaft axis O-O, such that the eccentric 46 is eccentrically rotated about the drive shaft axis O-O by the drive shaft 44. In the present embodiment, the eccentric member 46 includes an eccentric shaft 54 and an eccentric bearing 56 fitted over the eccentric shaft 54. The centerline S-S of the eccentric shaft 54 is oriented in the same direction as, but not collinear with, the drive shaft axis O-O so that the eccentric bearing 56 moves together eccentrically with respect to the drive shaft axis O-O as a result of the eccentric shaft 54. The eccentric bearing 56 has an outer surface that engages the shift fork 48 to drive the shift fork 48 to swing.

The drive shaft support 47 includes a receiving portion 49 for receiving the first support bearing 45, and a mating portion 51 disposed around the receiving portion 49 for fixed mounting to the housing 12. The receiving portion 49 is a hollow cylinder, and when the first support bearing 45 is mounted to the receiving portion 49, the first support bearing 45 is in interference fit with the inner side wall of the receiving portion 49, so that the position of the first support bearing 45 is stably limited, and the driving shaft 44 can be stably supported in the driving shaft support 47. The mating portion is fixedly attached to the motor housing portion 22 by

screws

53a and 53b, thereby achieving positional fixation of the drive shaft support member 47.

Further, in order to stabilize the position of the motor 14, a fixing member 55 is mounted at an end of the receiving portion 49 opposite to the motor 14, and the fixing member 55 is screwed with a screw hole on the motor 14 through two screws penetrating through the driving shaft supporting member 47, so as to fix the position of the motor 14 along the extending direction of the driving shaft axis O-O.

After the driving shaft 44 is mounted to the driving shaft support 47, the eccentric 46 protrudes from the central area of the housing 49 and the fixing piece 55 to cooperate with the fork 48, driving the fork 48 to oscillate.

The shift fork 48 is fixedly mounted on the swing output shaft 16 and protrudes from the swing output shaft 16 along a circumferential extension of the swing output shaft 16, and an extension direction thereof forms a fork extension direction. When the portable cutting machine 10 is in operation, the movement locus of the eccentric member 46 is in a plane perpendicular to the axis O-O of the driving shaft, and during the engagement of the eccentric member 46 and the fork 48, the direction of the frictional force generated therebetween is coplanar with the plane of the movement locus, i.e., the direction of the frictional force is perpendicular to the axis O-O of the driving shaft. Since the extending direction of the shift fork is different from the extending direction of the motor shaft, a part of the frictional force component force applied to the shift fork 48 by the eccentric member 46 in the direction perpendicular to the extending direction of the shift fork is offset by itself, thereby reducing the vibration of the shift fork 48 in the direction perpendicular to the extending direction of the shift fork. In this embodiment, the extending direction of the shifting fork is perpendicular to the extending direction of the driving shaft axis O-O, so that the eccentric member 46 does not generate displacement perpendicular to the extending direction of the shifting fork relative to the shifting fork 48, friction perpendicular to the extending direction of the shifting fork is not generated between the eccentric member 46 and the shifting fork 48, and the shifting fork 48 does not generate vibration perpendicular to the extending direction of the shifting fork. As a result, the transmission mechanism 18 is not substantially shaken or has less shaking by the eccentric 46 not being displaced relative to the fork 48 perpendicular to the second longitudinal extension, and the portable cutting machine 10 can use a motor with a rotation speed of 20000 rpm or more, even a motor with a rotation speed of 30000 rpm or more, and has better operation comfort.

Referring to fig. 7 and 9, the yoke 48 includes a driving portion 58 integrally extending in the extending direction of the yoke and engaged with the eccentric member 46, and a mounting portion 60 connected to the swing output shaft 16.

The driving part 58 includes first and second driving

arms

62a and 62b extending along the fork extending direction, respectively, and spaced apart from each other. The first drive arm 62a has a first drive surface 64a that the eccentric 46 contacts, the second drive arm 62b has a second drive surface 64b that the eccentric 46 contacts, and the first drive surface 64a faces the second drive surface 64b, sandwiching the eccentric 46 between the first drive surface 64a and the second drive surface 64 b. The vibrations between the fork 48 and the eccentric 46 are reduced by the first drive surface 64a and the second drive surface 64b simultaneously both being in contact with the eccentric 46.

In order to stabilize the structure of the fork 48, a connecting arm 64 is connected between the first driving arm 62a and the second driving arm 62b, and the connecting arm 64 is integrally formed with the first driving arm 62a and the second driving arm 62b, thereby optimizing the overall stress intensity of the fork 48.

The mounting portion 60 is used to be fixedly connected to the swing output shaft 16 to drive the swing output shaft 16 to swing. In the present embodiment, the mounting portion 60 is a body fixedly connected to the swing output shaft 16, and a connecting hole for being fitted over the swing output shaft 16 is formed at the center of the body.

Referring to fig. 6, 7 and 10, in order to prevent the eccentric member 46 and the fork 48 from being contaminated by dust and to prevent the eccentric member and the fork 48 from being damaged due to large friction force, a closed receiving space is provided in the portable cutting machine 10, and the eccentric member 46 and the fork 48 are received in the receiving space to prevent the eccentric member and the fork from being contaminated by dust and to maintain a lubricated matching state. In the present embodiment, the portable cutter 10 is further provided with a support seat 78 in the housing 12, and the support seat 78 is engaged with the drive shaft support 47 to form the housing space.

Referring to fig. 7, 11 and 12, a first receiving cavity 80 for receiving the eccentric member 46 and a portion of the shift fork 48 and a second receiving cavity 82 communicating with the first receiving cavity and mainly receiving the swing output shaft 16 are formed in the supporting seat 78. The first receiving cavity 80 has an open end that mates with the receiving portion 49 of the drive shaft support 47, and when the drive shaft support 47 is assembled to the support seat 78, a substantial portion of the receiving portion 49 is received in the open end, thereby enabling the eccentric member 46 to extend into the first receiving cavity 80 to mate with the shift fork 48. Further, the

screws

53a and 53b are screwed with the screw holes 83a and 83b provided on the support seat 78, so that the housing 12, the driving shaft support 47, and the support seat 78 are fixedly connected, thereby stabilizing the structure of the portable cutting machine 10.

Referring to fig. 11, 12 and 13, in order to facilitate the swing output shaft 16 to be mounted on the supporting seat 78, an opening 84, a first opening 86 and a second opening 88 are formed on a side wall of the second receiving cavity 82 away from the first receiving cavity 80 and along a direction of the driving shaft axis O-O of the motor 14 for receiving a portion of the swing output shaft 16. After the shifting fork 48 extends into the accommodating space from the opening 84, the swing output shaft 16 extends into the second accommodating cavity 82 from the first opening 86 and is assembled with the shifting fork 48, so that the swing output shaft 16 and the shifting fork 48 are mounted on the support seat 78. Furthermore, the supporting seat 78 is provided with a plug 89 which is matched with the opening 84, so that a closed accommodating space is formed inside the supporting seat 78 after the swing output shaft 16 and the shifting fork are installed on the supporting seat 78, namely, the first accommodating cavity 80 and the second accommodating cavity 82 form the accommodating space for hermetically accommodating the eccentric member 46 and the shifting fork 48.

In the present embodiment, in order to make the supporting seat 78 have better stress strength and better heat dissipation, the supporting seat 78 is made of a metal material, preferably an aluminum alloy material.

Referring to fig. 14, a screw hole 87 is further formed on the supporting base 78 for fixedly connecting with the supporting assembly 21, so that the supporting assembly 21 is stably fixed on the portable cutting machine 10. Because the shell 12, the motor 14, the transmission mechanism 18, the swing output shaft 16 and the support assembly 21 in the portable cutting machine 10 are directly and fixedly connected with the support seat 78, the components of the portable cutting machine 10 are closely connected together, the overall stress intensity is optimized, and the vibration is reduced to the greatest extent.

Referring to fig. 7 and 9, the swing output shaft 16 has an output shaft axis R-R, and the swing frequency of the swing output shaft 16 around the output shaft axis R-R is greater than or equal to 20000 rpm, so as to further drive the saw blade 20 to perform a cutting operation, which has a higher cutting efficiency, and further, the swing frequency of the swing output shaft 16 is greater than 30000 rpm, which has a better cutting efficiency.

The output shaft axis R-R of the swing output shaft 16 is arranged parallel to the drive shaft axis O-O. So set up and make swing output shaft 16 in the course of the work, can not produce the displacement along the ascending direction of output shaft axis R-R under the drive of shift fork 48 to reduce the vibrations of swing output shaft 16, make the cutting process more stable.

When the portable cutting machine 10 performs cutting operation, the direction of the friction force generated between the eccentric member 46 and the shifting fork 48 is perpendicular to the driving shaft axis O-O, at this time, the shifting fork 48 and the swing output shaft 16 are fixedly connected, so that the shifting fork 48 and the swing output shaft 16 are integrally subjected to the friction force perpendicular to the driving shaft axis O-O, and the output shaft axis R-R of the swing output shaft 16 and the driving shaft axis O-O are arranged in parallel, so that the direction of the friction force is perpendicular to the output shaft axis R-R, and the swing output shaft 16 is not subjected to the friction force along the extension direction of the output shaft axis R-R, so that the swing output shaft is not displaced along the extension direction of the output shaft axis R-R. Therefore, when the portable cutting machine 10 is in the cutting process, the swing output shaft 16 is driven by the transmission mechanism 18 to swing, and displacement along the direction of the axis R-R of the output shaft of the portable cutting machine 10 can not be generated, so that vibration generated in the working process of the portable cutting machine 10 is greatly reduced, and the operation comfort level is improved. In the present embodiment, the output shaft axis R-R of the swing output shaft 16 and the driving shaft axis O-O of the driving shaft 44 are parallel to each other and perpendicular to the extending direction of the fork, so that the vibration of the portable cutting machine 10 is minimized and the operation comfort is optimized.

One end of the swing output shaft 16 along the output shaft axis R-R is a tool mounting end 70 for mounting the saw blade 20, the other end is provided with a second support bearing 72, and a third support bearing 74 is further provided between the tool mounting end 70 and the second support bearing 72 to enable the swing output shaft 16 to be stably supported. The shift fork 48 is connected between the second support bearing 72 and the third support bearing 74 through the mounting portion 60, so that the shift fork 48 can stably drive the swing output shaft 16 to swing.

Referring to fig. 9 and 12, after the swing output shaft 16 is mounted to the supporting seat 78, the second supporting bearing 72 and the third supporting bearing 74 respectively and the inner side walls of the first opening 86 and the second opening 88 of the supporting seat 78 are in interference fit, so as to define the positions of the second supporting bearing 72 and the third supporting bearing 74, and further define the position of the swing output shaft 16, and the second receiving cavity 82 and the swing output shaft 16 are in a sealed connection by mounting the second supporting bearing 72 and the third supporting bearing 74, so as to prevent dust from entering the receiving space, and further prevent the eccentric 46 and the shifting fork 48 from being polluted.

The tool mounting end 70 is polyhedral in shape for accommodating the saw blade 20. A fastener 76 is also mounted at the tool mounting end 70 for capturing the saw blade 20 between the fastener 76 and the tool mounting end 70, thereby enabling mounting of the saw blade 20 to the portable cutting machine 10. In this embodiment, the tool mounting end 70 has a threaded bore with which a fastener 76 is form fit and has an end exposed to the threaded bore to clamp the saw blade 20 between the end and the tool mounting end 70. And a washer 77 is sleeved on the fastener 76, so that the fastener 76 and the tool mounting end 70 are effectively prevented from being loosened, and the saw blade 20 is stably mounted.

The swing frequency of the swing output shaft 16 during operation is 20000 times/min or more, and further, the swing frequency thereof can be set to 30000 times/min or more, thus providing the portable cutting machine 10 with higher cutting efficiency. In the present embodiment, the rotation speed of the swing output shaft 16 is equal to 20000 times/min, which allows the portable cutting machine 10 to have a long service life while satisfying high cutting efficiency.

Referring to fig. 14, the saw blade 20 is mounted on the swing output shaft 16 and swings together with the swing output shaft 16, so when the swing frequency of the swing output shaft 16 is 20000 times/min or more, the swing frequency of the saw blade 20 is 20000 times/min or more, correspondingly, when the swing frequency of the swing output shaft 16 is 30000 times/min or more, the swing frequency of the saw blade 20 is 30000 times/min or more. In the present embodiment, the oscillation frequency of the saw blade 20 is equal to 20000 times/min.

Blade 20 includes a lengthwise extending coupling portion 90 and a base portion 92.

The connecting portion 90 has a flat plate shape having two first and

second side walls

92a and 92b opposite to each other and extending in a longitudinal direction of the connecting portion 90, and a third side wall 92c adjacent to each of the first and

second side walls

92a and 92b and having a mounting hole 94. First and

second sides

96a and 96b are formed at positions where the first and

second side walls

92a and 92b, respectively, adjoin the third side wall 92 c.

The periphery of the mounting hole 94 formed in the third sidewall 92c is in a circular arc transition that semi-surrounds the mounting hole 94, and the circle center of the circular arc is overlapped with the circle center of the mounting hole 94, which can save the reserved space of the portable cutting machine 10 for the saw blade 20, and make the cooperation between the saw blade 20 and the portable cutting machine 10 smoother when the saw blade 20 swings.

The shape of the mounting hole 94 may be polygonal, circular, or other shapes that are centrosymmetric, and in the present embodiment, the shape of the mounting hole 94 is polygonal, which can be matched with the shape of the polyhedron of the tool mounting end 70, so that when the swing output shaft 16 swings, the saw blade 20 can be driven without relative sliding, and the saw blade 20 can be limited to a plurality of different angular positions as required. When the saw blade 20 is assembled to the portable cutting machine 10, the mounting hole 94 is fitted over the swing output shaft 16, and the relative positional relationship therebetween is fastened by the fastener 76. When the portable cutting machine 10 works, the saw blade 20 is driven by the swing output shaft 16 to form a swing plane, the swing plane is perpendicular to the output shaft axis R-R of the swing output shaft 16, that is, the swing plane is parallel to the lengthwise extension direction of the holding portion, so that the user can push the portable cutting machine 10 to perform cutting work through the holding portion 28. In the present embodiment, the extension planes of the first side wall 92a and the second side wall 92b are perpendicular to the swing plane.

The base 92 extends in the direction from the first side 96a to the second side 96b, projects from the second side wall 92b away from the mounting hole 94 by the connection portion 90, and the base 92 is a portion behind the projecting connection portion 90. The base 92 has a cut away portion on the side of the coupling portion 90 that is away from the mounting hole 94 in the lengthwise direction, i.e., at the end of the blade 20 that is away from the swing output shaft, and the base 92 has a surface 98 that abuts the cut away portion. In this embodiment, the base 92 extends only in the direction from the first side 96a to the second side 96b, and the cutting portion is a serration 100 comprising a plurality of serrations, and the surface 98 is coplanar with the oscillation plane when cutting the workpiece.

In the present embodiment, the base 92 extends from the second side wall 92b uniformly to the connecting portion 90, i.e., has a constant width in the extending direction, so that the base 92 has a high stress strength and is not easily broken during the cutting of the workpiece by the serration 100. Each of the saw teeth of the saw tooth portion 100 includes a tooth tip and a tooth root, the tooth tips form a cutting line along a straight line, the straight line of the tooth tips continuously swing to cut a workpiece under the driving of the swing output shaft 16, and the tooth root is used for fixedly connecting the saw teeth with the base portion 92.

In order to adapt portable cutting machine 10 to swing cutting, the length of the connecting portion in its longitudinal direction must be sufficient to allow the teeth to swing more than the distance between the tips of adjacent teeth, limited by the swing angle of portable cutting machine 10 and the distance between the tips of adjacent teeth, and the specific dimensions are not described in detail herein.

The length L of the base 92 along the extending direction and the width W of the base 92 relative to the extending direction can be set to different sizes according to different use requirements, for example, the length L of the base 92 can range from 2 mm to 80 mm, wherein the preferred length can be selected from 15 mm to 40 mm, and the preferred length is selected from 20 mm to 35 mm. The width W of the base 92 may range from 5 mm to 11 mm, wherein the preferred width may be selected from 7 mm, 8 mm and 9 mm, i.e., 7 mm to 9 mm. The selection of the saw blade 20 with the preferred length and width enables a better cutting effect to be achieved for cutting the workpiece.

The connecting portion 90 may be formed in two parts, one part being provided with the mounting hole 94 and the other part being provided with the base portion 92. The thickness of the portion of the connecting portion 90 having the mounting hole 94 is larger than the portion having the base portion 92, and the two portions are fixedly connected by welding, riveting or the like, so that the saw blade 20 can be conveniently processed and manufactured, and different thicknesses are set according to different functional purposes between different regions of the connecting portion 90, so that the saw blade 20 has better stress strength and better cutting effect.

According to different use requirements, the cutting line of the sawtooth part 100 and the first side wall 92a can be set to different angles δ, and the angle δ can range from 65 ° to 120 °, wherein the preferred angle value can be selected from 80 ° to 110 °. The angle δ is selected to have the above-mentioned preferable angle value, so that the cutting performance of the saw blade 20 can be exerted to a preferable state.

In order to stabilize the connection structure between the base 92 and the connecting portion 90, and prevent the joint between the base 92 and the connecting portion 90 from breaking during the process of cutting the workpiece by the saw blade 20, a curved transition may be provided at the joint between the surface of the base 92 facing away from the sawtooth portion 100 and the second side wall 92b of the connecting portion 90, where the base 92 is a portion extending out of the connecting portion 90 after the curved transition.

The base portion 92 and the connecting portion 90 may not be formed as a single body, i.e., the base portion 92 and the connecting portion 90 are fixed together by welding or riveting. At this time, the surface 98a is parallel to the swing plane.

To improve the safety of the saw blade 20 during the cutting of the curved surface, the end wall of the connecting portion 90 adjacent to the cutting portion 100 is not provided with teeth, and is preferably provided with a flat surface. So when the user carries out cutting work, if the maloperation will inside the end wall stretches into the work piece, the user just can't promote portable cutting machine 10 cutting forward this moment, when having avoided the user to carry out the curved surface cutting, changes the cutting direction and leads to connecting portion 90 by the work piece twist-off, has further avoided the part departure of twist-off to hurt the user.

Of course, in order to increase the effective cutting length of the saw blade 20 when it is not used for cutting curved surfaces, the connecting portion 90 may be provided with saw teeth at its end surface away from the mounting hole 94, and the saw teeth of the connecting portion 90 and the saw teeth of the saw tooth portion 100 are aligned in a straight line. Also, to facilitate cutting of the blade 20 at a location in the plane of the workpiece when used alone, a bevel may be provided on the connecting portion 90 and between the mounting hole 94 and the location where the connecting portion 90 is attached to the base 92. Of course, the saw blade 20 may have only the serrations 100 without the serrations provided on the coupling portion 90 and without the bevel.

The saw blade 20 is improved in structure of the conventional saw blade, so that the portable cutting machine provided with the output swing of the saw blade 20 can cut a curved surface on a workpiece, and the function of the conventional swing cutting machine is expanded. That is, when the user uses the saw blade 20 of the present invention to cut a workpiece, the user can only use the base 92 to cut the workpiece, and since the base has a narrow width and extends from one side of the connecting portion of the saw blade, the user can cut a curved surface with any shape on the surface of the workpiece under the driving of the swing output shaft, which brings convenience to the work and life of the user and greatly meets the needs of the user.

Referring to fig. 1, 15 and 16, the portable cutting machine 10 performs a cutting operation by abutting a support assembly 21 against a workpiece. The support assembly 21 includes a base plate 102 for abutting against a surface of a workpiece, and a connection assembly 104 for connecting the base plate 102 to the portable cutter 10.

The base plate 102 has a substantially flat plate shape having an abutting surface for abutting against a workpiece when the portable cutting machine 10 cuts the workpiece, so that the cutting operation is more stable, and vibration during the cutting process can be reduced to prevent damage to the saw blade 20 due to the vibration. When the base plate 102 is assembled to the portable cutting machine 10, the output shaft axis R-R of the swing output shaft 16 is parallel to the abutting surface, thereby facilitating cutting of a workpiece with the saw blade 20 in a direction perpendicular to the abutting surface. When the portable cutter 10 is abutted against the surface of the workpiece to perform cutting work, the projection of the center of gravity of the portable cutter 10 on the surface of the workpiece is located in the abutting surface, so that the portable cutter 10 can be stably supported without rollover.

A blade slot 106 is provided in the base plate 102 extending along the long side so that the blade 20 can extend from the blade slot 106 and through the abutment surface for cutting work.

A guide assembly 108 is disposed at an end of the blade slot 106 remote from the swing output shaft 16. The guide assembly 108 is used to provide a guide for the oscillating movement of the saw blade 20 to reduce vibrations of the saw blade 20 during the oscillating movement to cut a workpiece. In this embodiment, the guide assembly 33 includes a first guide roller 108a and a second guide roller 108b disposed opposite to each other on both sides of the blade slot 106. When the portable cutting machine 10 cuts a workpiece, the saw blade 20 is held between the first guide roller 108a and the second guide roller 108b, and abuts against one of the rollers (the first guide roller 108a or the second guide roller 108b) when the saw blade 20 cuts a curved surface, and at the moment, the roller (the first guide roller 108a or the second guide roller 108b) rotates, so that the swinging motion of the saw blade 20 is not hindered. Preferably, the saw blade 20 is adjacent to the saw tooth portion 100 at the contact area with the first guide roller 108a or the second guide roller 108b, and the contact area is spaced from the tooth root by a distance greater than 1 mm and less than 20 mm, so that the guide assembly 33 has a good guiding and damping effect, and a distance of 1 mm is reserved between the two guide rollers and the tooth root, thereby effectively avoiding the problem of wear between the guide rollers and the saw tooth due to the installation tolerance of the guide rollers.

The abutting surface of the bottom plate 102 is not limited to rectangle, and can be made into other shapes such as circle, triangle, other polygon and so on.

The position of the base plate 102 relative to the swing output shaft 16 is adjustable, so that the base plate 102 can be adapted to saw blades of different sizes, and requirements of different working conditions can be met. In the present embodiment, the swinging plane of the saw blade 20 is perpendicular to the abutting surface, so that the projection of the swinging plane on the abutting surface is a straight line, and the bottom plate 102 can only adjust the position relative to the swinging output shaft 16 along the extending direction of the straight line, as shown in fig. 1 and 17, so that the arrangement can meet the requirements that the bottom plate 102 can be adapted to saw blades of different sizes, and the structure is simple and convenient to adjust.

The base plate 102 and the connecting assembly 104 are connected by a locking mechanism, and the locking mechanism is operable in a first state of releasing the base plate to enable the position of the base plate to be adjusted relative to the swing output shaft, and a second state of locking the position of the base plate relative to the swing output shaft, thereby enabling a user to fix the position of the base plate 102 as desired.

In the present embodiment, the locking mechanism includes a boss 110 disposed on a surface of the base plate 102 facing away from the abutting surface, a locking screw 114 penetrating the boss 110 and capable of being screwed with the connecting member 104, and a nut 115 corresponding to the locking screw 114.

The boss 110 has a long side and a short side perpendicular to each other, and the long side is parallel to the long side of the base plate 102, and a groove is correspondingly formed on the abutting surface at a position corresponding to the boss 110 to receive the locking screw 114. An adjusting slot 112 is formed on the boss 110, penetrates through the boss 110 and extends in the same direction as the saw blade slot 106, and a locking screw 114 is installed in the groove on one side of the abutting surface and passes through the adjusting slot 112 to be in threaded connection with the connecting component 104.

In the present embodiment, the number of the locking screws 114 is two, thereby achieving a stable position defining the base plate 102, and a spacer is provided between the locking screws 114 and the base plate 102 to prevent the locking screws 114 from damaging the base plate 102.

When a user needs to use different saw blades for cutting work, the position of the bottom plate 102 needs to be adjusted to enable the guide assembly 33 to be adapted to different sizes of each saw blade, at which point the user can loosen the locking screw 114, and the bottom plate 102 can slide relative to the locking screw 114 through the adjustment slot 112 to enable the bottom plate 102 to be adjusted in position relative to the swing output shaft 16 along the cutting direction, at which point the first state of the locking mechanism is achieved; when the user has adjusted the position of the base plate 102 and has locked the locking screw 114, the base plate 102 is locked in position relative to the swing output shaft 16, and the locking mechanism is in the second state.

The attachment assembly 104 includes a support 116 to which the locking screw 114 is attached, and an assembly 118 for mounting to the portable cutting machine 10.

The mount 116 is mounted to the boss 110 of the base plate 102, and the mount 116 has a guide plate that provides a guide for the boss 110 as it moves. In the present embodiment, the guide plates are two side plates 118 oppositely disposed on the support 116, and the two side plates 120 are respectively located at one side of the boss 110, so that the boss 110 is clamped between the two side plates 120, and the facing surfaces of the side plates 120 and the boss 110 are attached to each other, thereby achieving stable guiding through the two side plates 120 when the bottom plate 102 is adjusted.

A coupling plate 122 is provided between the two side plates 120, and a screw hole corresponding to the locking screw 114 is provided on the coupling plate 122 for the locking screw 114 to pass therethrough to be screw-coupled with the nut 115.

The assembly 118 is fixed by screws to the side of the support 116 facing away from the base plate 102 and further to the support seat 78 in the housing 12, thereby fixing the support member 21. Because the supporting seat 78 is made of metal, the stress strength is better, and the supporting component 21 can be stably installed on the supporting seat 78.

When the portable cutting machine 10 cuts a workpiece, the support assembly 21 abuts against the surface of the workpiece, the saw blade 20 cuts the workpiece under the driving of the swing output shaft 16, and the third side wall 92c of the saw blade 20 is perpendicular to the abutting surface of the bottom plate 70. In this embodiment, it is assumed that the range of the included angle between the abutting surface and the cutting line of the sawtooth portion 100 is α, the angle of the swing output shaft 16 outputting the swing angle is β, when the swing output shaft 16 is at the swing angle of β/2, the included angle between the abutting surface and the cutting line is γ, the maximum angle of α is γ + β/2, and the minimum angle of α is γ - β/2. The value of γ is selected from 80 ° to 100 °, and at this time, the portable cutting machine 10 has a relatively good cutting effect, and preferably, the value of γ is 90 °, so that the portable cutting machine 10 can achieve an optimal cutting effect. The value of β may be 2.8 °, 3.2 °, 4 °, or the like, and the range of α may be obtained by calculation, for example, when γ is 80 ° and β is 3.2 °, the value of α ranges from 78.4 ° to 81.6 °; when γ is 90 ° and β is 3.2 °, α ranges from 88.4 ° to 91.6 °, and the rest of the cases are not listed.

In order to accelerate the heat dissipation speed of the saw blade 20 in the cutting process, a fan can be arranged in the shell 12 of the portable cutting machine 10, an air outlet facing the saw blade 20 is formed in the position, close to the saw blade 20, of the shell 12, and an air duct for flowing air flow is formed between the fan and the air outlet, so that the fan can drive the air flow to the saw blade 20 through the air duct and the air outlet, the cooling speed of the saw blade 20 can be accelerated, the saw blade 20 is prevented from being broken due to overhigh temperature, and meanwhile, a user is prevented from being scalded due to the fact that the user contacts the saw blade 20.

Referring to fig. 1 and 18, in the present embodiment, the housing 12 is provided with the air outlet 124 along the circumferential direction of the output shaft axis R-R of the swing output shaft 16, and the air outlet faces the longitudinal extending direction of the connecting portion 90 of the saw blade 20, so that the air flow flowing out from the air outlet 124 can pass through the surface of the saw blade 20 in the largest area, and the best heat dissipation effect is achieved.

The fan is mounted on a motor shaft of the motor 14, and is a motor fan 40 for dissipating heat from the motor, and a through air duct is provided between the motor housing 22 and the air outlet 124, so that air generated by the motor fan 40 can flow to the air outlet 124 through the air duct and flow from the air outlet 124 to the saw blade 20. In the present embodiment, the air duct inlet 126 is disposed on the circumferential sidewall of the motor accommodating portion 22 along the driving shaft axis O-O, and the air duct inlet 126 is close to the motor 14, so that heat generated during the operation of the motor 14 can be taken away before the air flow enters the air duct, and the air flow generated during the operation of the motor fan 40 can be fully utilized to dissipate heat for the motor 14 and the saw blade 20.

Referring to fig. 18 and 19, the air duct inlet 126 is disposed on the right half shell 37, and the air outlet 124 is disposed on the left half shell 35, so that the air duct needs to extend from the right half shell 37 to the left half shell 35, wherein the air duct passes through the supporting seat 78, and at this time, the air flow flowing through the air duct can take away the heat generated by the cooperation of the eccentric 46 and the shifting fork 48, thereby achieving heat dissipation for the transmission mechanism.

In the present embodiment, a through hole 128 penetrating through the supporting seat 78 is formed on the supporting seat 78 at a position corresponding to the right half shell 37 and the left half shell 35, at this time, an open air duct is formed by passing through the air duct inlet 126 of the right half shell 37 to the through hole 128 of the supporting seat 78 and finally reaching the air outlet 124 of the left half shell 35, at this time, the air flow generated by the motor fan 40 can firstly dissipate heat for the motor 14, and then the air flow enters the air duct from the air duct inlet 126 and then flows through the through hole 128, at this time, the air flow can take away heat generated by friction between the eccentric member 46 and the shift fork 48 on the supporting seat 78, and finally the air flow flows from the air outlet 124 to the saw blade 20, and further dissipates heat for the saw blade 20, so that the heat dissipation performance of the.

In order to avoid the pollution of the eccentric member 46 and the shift fork 48 caused by the dust carried by the airflow of the air duct when the airflow directly flows through the eccentric member 46 and the shift fork 48, the through hole 128 is not communicated with the accommodating space, but preferably the thickness of the side wall between the eccentric member and the shift fork is less than 20 mm, and the accommodating space has a better heat dissipation effect. Preferably, the thickness of the sidewall is less than or equal to 5 mm, such as 5 mm, 4 mm, 3 mm, 2 mm, 1 mm, or 0.5 mm.

In order to increase the intensity of the air flow entering the air duct inlet 126, the motor fan 40 is designed as a centrifugal fan, and the air duct inlet 126 is arranged along the circumferential direction of the motor accommodating portion 22 in a matching manner, so that the flow speed of the air flow in the air duct is increased, and a better heat dissipation effect is achieved. Furthermore, the inner diameter of the circumferential side wall of the motor accommodating portion 22 gradually increases along the direction from the air inlet hole 23 to the air duct inlet 126, so that the flow velocity of the air flowing through the air duct is further increased, and the heat dissipation efficiency is optimal.

Referring to fig. 1, the baffle 125 is disposed on the left half shell 35, the baffle 125 is disposed at a circumferential position of a portion of the swing output shaft 16 extending out of the shell 12, and the air outlet 124 is disposed on the baffle 125, so that an air flow flowing out is blown toward a cutting direction of the saw blade 20, thereby dissipating heat of the saw blade 20 and blowing away chips generated during a cutting process of the saw blade, so that a better view is provided for the cutting operation.

Of course, it is also possible for a heat dissipation fan independent of the motor fan 40 to be disposed in the housing 12, and the heat dissipation fan can be directly disposed at a position corresponding to the air outlet 124, so as to achieve a fast flow rate of the air flowing out from the air outlet 124 and achieve an optimal heat dissipation for the saw blade 20. It is needless to say that other design changes are possible to those skilled in the art, and the same or similar functions and effects to those of the present invention are also included in the scope of the present invention.

Referring to fig. 20, a saw blade 130 of a portable cutting machine according to a second embodiment is shown. The saw blade 130 includes a connecting portion 134 having a mounting hole 132, a base portion 138 extending from a second side wall 136b of the connecting portion 134 to the connecting portion 134, and serrations 139 disposed on the base portion 138.

The function and structure of the saw blade 130 are substantially the same as those of the saw blade 20 provided in the first embodiment, except that: the horizontal distance from the end surface of the connecting portion 134 far away from the mounting hole 132 to the center of the mounting hole 132 is greater than the horizontal distance from any point on the base portion 138 to the center of the mounting hole 132, that is, the end of the connecting portion 134 far away from the mounting hole 132 horizontally protrudes out of the base portion 138. When the portable cutting machine cuts a curved surface on a workpiece through the saw blade 130, only the base 138 can cut in a slit cut by the workpiece, and the protruding part of the connecting part 134 can be blocked by the plane of the workpiece, so that the connecting part 134 cannot enter the slit cut by the workpiece, the connecting part 134 can be prevented from entering the slit cut by the workpiece, the connecting part 134 is prevented from being damaged by the saw blade 130 due to the fact that the connecting part 134 is pressed by the curved surface in the direction perpendicular to the swinging plane, meanwhile, a user can be reminded of needing to adjust the angle, the protruding part of the connecting part 134 is not in contact with the surface of the workpiece, and the cutting process is safer and.

Referring to fig. 21, a saw blade 140 of a portable cutting machine according to a third embodiment is shown. The blade 140 includes a coupling portion 144 having a mounting hole 142, and a base portion 148 extending from a second side wall 146b of the coupling portion 144 to the coupling portion 144.

The function and structure of the blade 140 is substantially the same as the blade 20 provided in the first embodiment, except that: the first side wall 146a of the connecting portion 144 and the end wall of the connecting portion 144 away from the mounting hole 150 are in arc transition. So set up, can reduce the quality of saw bit 140 to in the in-process of cutting the work piece, the vibrations of saw bit 140 are less, make the cutting more accurate, and it is difficult to be damaged by vibrations itself.

Referring to fig. 22, a saw blade 152 of a portable cutting machine according to a fourth embodiment is shown. The blade 152 includes a coupling portion 156 having a mounting hole 154, and a base portion 160 extending from a second side wall 158b of the coupling portion 156.

The saw blade 152 is substantially identical in functional configuration to the saw blade 20 provided in the first embodiment, except that: the cutting part of the base part 160 is the sawtooth part 162, and the tooth tips of the sawtooth part 162 are arranged along an arc, thereby forming an arc-shaped cutting line, and thus the cutting efficiency can be effectively improved. Preferably, the circle center of the circular arc cutting line coincides with the circle center of the mounting hole 154, so that the vibration generated when the saw blade 152 cuts the workpiece can be effectively reduced. The side wall of the base 160 facing away from the teeth 162 extends along a straight line, which effectively reduces the space occupied by the base 160, thereby making the blade 152 more flexible when cutting a curved surface in a workpiece.

The base 160 extends out of the connecting portion 156 and then extends out by a certain length, so as to form an extending direction of the base 160, a point of the circular arc cutting line is sequentially selected along the extending direction of the base, an intersection point exists between a connecting line of the point and the circle center of the mounting hole and the side wall of the base 160 back to the sawtooth portion 162, and a difference h is made between the length of the connecting line and the distance from the circle center of the mounting hole to the intersection point, and then the difference h is sequentially reduced. In the present embodiment, the maximum value of the difference h is 20 mm, and the saw blade 152 can achieve a better cutting effect when cutting the workpiece.

Of course, if the two free ends of the circular arc-shaped cutting line are connected with the circle center of the circular arc-shaped cutting line to form a sector, when the circle center of the mounting hole 154 is located outside the sector area, that is, the circle center of the mounting hole 154 is not overlapped with the circle center of the circular arc-shaped cutting line, at this time, the maximum value of the difference h may be set to be smaller, for example, less than 20 mm, and the specific value is determined according to a specific design scheme. This arrangement effectively reduces the width of the base 160, thereby making it easier to cut a curved surface.

Due to the structural configuration and size, it is possible that not all of the connecting lines intersect the side wall of the base 160 opposite to the serrated portion 162, but if there are some intersecting portions satisfying the above description, the scope of the present invention is covered.

Referring to fig. 23, in order to further improve the cutting efficiency, the saw teeth of the saw tooth portion 162 may extend obliquely with respect to the base portion 160 and extend toward the first side 164 of the connecting portion 156, i.e., the saw teeth extend in a direction opposite to the extending direction of the base portion 160. If the base plate described in the previous embodiment is installed on the portable cutting machine at this time, the saw teeth are arranged in such a way that the position relationship between the base plate and the workpiece is tightened during the cutting process, so that the base plate and the workpiece are matched more closely, and the vibration during the cutting process can be reduced.

Referring to fig. 22, in order to increase the effective cutting length of the saw blade 152 when it is not used for cutting a curved surface, the end surface of the connecting portion 156 away from the mounting hole 154 is provided with saw teeth arranged along the same circular arc line as the saw teeth of the saw tooth portion 162.

Referring to fig. 24 and 25, a portable cutter 166 according to a fifth embodiment of the present invention includes a housing 168, a motor (not shown), a transmission mechanism (not shown), a swing output shaft 170, a support assembly 172, a fastener 174, and a saw blade 176.

The housing 168 includes a body housing 178 and a head housing 180, and the body housing 178 and the head housing 180 are connected by screws.

The motor is disposed within the body housing 178 and is driven in rotation by the motor shaft. The transmission mechanism is located in the body case 178 and the head case 180, and converts the rotation output by the motor into a swing motion, and drives the swing output shaft 170 to output the swing. The swing output shaft 170 is accommodated in the head housing 180, and one end thereof is polyhedral and extends out of the head housing 180, and a threaded hole for screw-coupling with the fastening member 174 is provided in a central region of the end in the axial direction of the swing output shaft 170. In order to make the connection between the fastener 174 and the swing output shaft 170 more stable, a washer 175 is fitted over the fastener 174.

The support assembly 172 includes a connector 182 and a base plate 184. When the support assembly 172 is assembled to the portable cutter 166, the connecting member 182 is sandwiched between the saw blade 176 and the head housing 180, such that the connecting member 182 is effectively prevented from falling off the head housing 180, and the bottom plate 184 provides support for the saw blade 176 to cut a workpiece.

Please refer to fig. 25 and 26. The connector 182 is made of a flexible material, and has first and

second housings

186 and 188, and a circular hole 190 formed between the first and second housings. Which can be sleeved outside the head housing 180 and used to fix the positional relationship between the support assembly 172 and the portable cutter 166. In this embodiment, the connector 182 is a plastic product.

The connector 182 is made of a flexible material in order to enable it to be more closely fitted to the head housing 180. After the connecting member 182 is sleeved to the head housing 180, the dimensional tolerance can be overcome by the elastic deformation of the flexible material, so that the connecting member 182 and the head housing 180 are tightly matched. The flexible material may also be rubber, metal with better flexibility, etc., and is not specifically listed herein, but according to the disclosure of the present invention, the flexible material should be covered by the scope of the present invention as long as it can achieve the same or similar functions and effects as the flexible material.

The first housing 186 and the second housing 188 are matched with the head shell 10 of the portable cutter 166, that is, when the supporting assembly 172 is assembled on the portable cutter 166, the supporting assembly is sleeved on the head shell of the portable cutter through the connecting piece 182, at this time, the connecting piece 182 is positioned between the saw blade 176 and the head shell 180, and the swing output shaft 170 extends out of the circular hole 190 to drive the saw blade 176 to work. The annular steel ring 192 is arranged on the side wall of the hole of the circular hole 190 to prevent the saw blade 176 from directly contacting with the hole wall of the circular hole 190 to abrade the hole wall in the working process, thereby protecting the connecting piece 182.

To better define the position of the connector 182, the frictional resistance between the connector 182 and the housing 168 may be increased, such as by providing a non-slip layer, such as a rubber coating, or a rubber band, on the surface of the first housing 186 and/or the second housing 188 facing the portable cutter 166. Of course, the person skilled in the art can also define the position relationship between the connecting member 182 and the portable cutter 166 by other means, but the invention should be covered by the scope of the invention as long as the function and effect achieved by the invention are the same or similar.

Screw holes 193 are provided at positions of the first housing 186 and the second housing 188 around the circular hole 190, respectively, for fixedly coupling with the bottom plate 184. Of course, the positions and the number of the screw holes 193 are not limited to the above description, and may be set at other positions according to the structural arrangement requirement, and the number may be set to three, four, etc., as long as the positional relationship between the connecting member 182 and the bottom plate 184 can be firmly fixed.

The support assembly 172 can be conveniently mounted on the portable cutter 166 through the connecting member 182, that is, the connecting member 182 is sleeved outside the head shell 180 of the portable cutter 166, when the connecting member 182 needs to be detached, the fastening member 174 is firstly detached, and then the connecting member 182 and the saw blade 176 can be taken down from the portable cutter 166, so that great convenience is brought to a user.

Please refer to fig. 25 and 27 together. The base plate 184 includes a coupler 194, an abutment plate 196 and a guide assembly 198.

The adapter 194 is disposed on the abutting plate 196 and protrudes from the surface of the abutting plate 196, and is integrally formed with the abutting plate 196, so that the overall stress strength of the bottom plate 184 is better. A through hole 200 is provided at a central position of the coupling 194. When the support assembly 172 is assembled to the portable cutter 166 and the axis of the through hole 200 coincides with the axis of the swing output shaft 170, the user can observe whether the mounting hole 52 of the saw blade 176 is fitted to the swing output shaft 170 through the through hole 200 when the user removes the saw blade 176, and can mount or remove the fastener 174 through the through hole 200. Thus, the user does not need to detach the support assembly 172 when detaching or mounting the saw blade 176, which is convenient for the user.

A base plate screw hole 202 is provided in the area of the adapter 194 surrounding the through hole 200. The number and positions of the bottom plate screw holes 202 correspond to those of the screw holes 192 of the connector 182, and in the present embodiment, the number of the bottom plate screw holes 202 is two, and the positions thereof correspond to those of the two screw holes 192 of the connector 182, respectively. When the abutment plate 196 is mounted to the link 182, the positional relationship is locked by two screws 204.

The abutting plate 196 is substantially in the shape of a flat plate, and the surface of the abutting plate facing away from the coupling 194 is an abutting surface for abutting against the surface of the workpiece when the portable cutter 166 cuts the workpiece, so that the cutting operation is more stable, and the vibration during the cutting process can be reduced to prevent the saw blade 176 from being damaged by the vibration. The abutting surface is substantially rectangular and has a pair of long side lines and a pair of short side lines, and when the supporting assembly 172 is assembled on the portable cutting machine 166, the projection of the axial extension line of the swing output shaft 170 on the extension plane of the abutting surface is perpendicular to the long side lines and parallel to the short side lines. In the two short sidelines, the projection distance between the short sideline relatively far away from the swing output shaft and the swing output shaft 170 on the abutting surface is X; the projection distance between the axis of the swing output shaft 170 and the saw teeth of the saw blade 176 on the abutting surface is Y, and the projection distance Y is the maximum projection distance between the axis and the saw teeth on the abutting surface because the number of the saw teeth can be multiple; in the present embodiment, the projection distance X is greater than or equal to the projection distance Y, so that the supporting assembly 172 can be more stably and reliably supported when the saw blade 176 cuts the workpiece. Preferably, the projection distance X is more than or equal to 40 mm, so that the cutting stability can be further improved.

At the end of the abutment plate 196 remote from the attachment 194, a slot 204 is provided extending lengthwise along the abutment plate 196 for receiving the saw blade 176 when the portable cutter 166 is cutting a workpiece, such that the saw blade 176 can cut the workpiece through the slot 204.

To increase the stress intensity of the abutment plate 196, several ribs may be provided on the surface of the abutment plate 196 where the adapter 194 is provided.

The guide assembly 198 includes a fixed plate 206 and two rollers 208.

The fixing plate 206 is in the shape of a square flat plate, and is fixed by screws at positions where the slots 204 are provided in the base plate 184. The fixing plate 206 has a fixing plate slot 210 corresponding to and extending in the same direction as the slot 204, and the function and effect thereof are the same as those of the slot 204. A roller 208 is provided at a position opposite to the notch of the fixing plate slot 210, respectively. When the portable cutting machine 166 cuts a workpiece, the saw blade 176 is kept between the two rollers 208, the saw blade 176 abuts against one of the rollers 208 when the curved surface is cut, the roller 208 rotates at the moment, and the swinging movement of the saw blade 176 is not hindered.

The abutment surface of the abutment plate 196 is not limited to a rectangle, but may be formed in other shapes such as a circle, a triangle, other polygons, and the like. Accordingly, the shapes of the abutment plate 196, the coupling member 194 and the guide member 198 may be modified accordingly, and the modifications thereof, which are identical in technical spirit to the present invention or are within the common knowledge of those skilled in the art, are also included in the scope of the present invention.

Referring to fig. 28 to 30, a support assembly 212 of a portable cutting machine according to a sixth embodiment of the present invention is shown. The support assembly 212 includes a base plate 216 having a connector 214.

The support assembly 212 is substantially the same as the support assembly 172 provided in the fifth embodiment in terms of functional structure, except that: the base plate 216 includes a mounting plate 218 connected to the connector 214, an abutment plate 220 assembled to the connector, and a guide assembly 222 mounted to the abutment plate 220.

The mounting plate 218 is made of a plastic material, and has a rectangular parallelepiped shape with an upper surface 224a and a lower surface 224 b. One end of the upper surface 224a along the longitudinal direction of the mounting plate 218 is connected to the connector 214, and in this embodiment, the mounting plate 218 and the connector 214 are formed as a single body. A plurality of screw holes are provided on the upper surface 224a for fixing the positional relationship with the abutment plate 220 by screws. The upper surface 224a is provided with a slot 226 at an end of the mounting plate 218 remote from the connector 214 in the longitudinal direction, and the slot 226 extends along the longitudinal direction. The slot 226 has a notch 226a, and the sidewall of the notch 226a forms a recess, reserving a space for the guide member 222. Lower surface 224b mates with abutment plate 220 when mounting plate 218 is assembled with abutment plate 220.

The abutting plate 220 is made of a metal material, has a rectangular parallelepiped shape, and has an abutting surface 220a for abutting against a workpiece. A surface 220b of the abutment plate 220 facing away from the abutment surface 220a is adapted to mate with a lower surface 224b of the mounting plate 218. The surface 220b is provided with screw holes corresponding to the screw holes of the mounting plate 218, so that the abutment plate 220 and the mounting plate 218 can be fixed in position by screws. In the present embodiment, the abutting plate 220 is made of a stainless steel plate, so that the abutting plate 220 has excellent wear resistance.

The abutment plate 220 is provided with an abutment plate slot 228 corresponding to the location of the slot 226 of the mounting plate 218, and the slot 226 and the abutment plate slot 228 extend through the base plate 216 to enable a blade of the portable cutting machine to cut a workpiece through the slot.

Some measures can be taken to stabilize the position relationship between the mounting plate 218 and the abutting plate 220 and prevent the mounting plate 218 from being worn, in this embodiment, the edge of the surface 220b of the abutting plate 220 is provided with a folded edge bending to the mounting plate 218, so that the mounting plate 218 is effectively protected and can play a role of further limiting.

The guide member 222 is disposed at a notch of the abutment plate slot 228, and when the abutment plate 220 is assembled with the mounting plate 218, the guide member 222 extends out of the upper surface 224a of the mounting plate 218 from the notch 226a of the slot 226. The specific functional structure of the guide assembly 222 is substantially the same as that of the guide assembly 198 of the fifth embodiment, and is not repeated here for purposes of brevity.

In the present embodiment, the supporting assembly 212 has a simple structure, so that the overall structure is more compact, the overall stress intensity is greatly improved, and the supporting is more stable and reliable.

Referring to fig. 31 and 32, a support assembly 230 of a portable cutting machine according to a seventh embodiment of the present invention is shown.

The support assembly 230 is substantially the same as the support assembly 212 provided in the sixth embodiment in terms of functional structure, except that: the abutting plate 232 of the bottom plate 230 has a first plane 232a and a second plane 232c on the side facing the workpiece, wherein the second plane 232c is used for abutting against the workpiece, and the extension planes of the first plane 232a and the second plane 232c intersect, so that the abutting part 233 is provided with a slot and the part mounted with the guide component 234 is tilted away from the first plane 232 a. So set up can effectual reduction vibrations to the influence of cutting, the saw bit can pass promptly the fluting, then the cutting work piece, so the saw bit is most violent with the position vibrations of work piece contact, in this embodiment, support the backup plate 232 and only support by first plane 232a and support the work piece, and second plane 232c can be towards the direction perk of keeping away from the work piece, thereby make support the backup plate 232 can not take place to contact with vibrations most violent region, thereby the vibrations of bottom plate 230 have been reduced, and then the vibrations that transmit for portable cutting machine by bottom plate 230 have been reduced, very big improvement user's use travelling comfort.

The support assembly and the saw blade introduced by the plurality of the embodiments can be independently used as a set of accessory products, and the base plate is installed on the portable cutting machine in a sleeved connection mode, so that the shell of the portable cutting machine does not need to be improved, the support assembly and the saw blade have wide applicability, and convenience is brought to a user. Of course, the saw blade used in conjunction with the bottom plate is not limited to the above-described structure, and other saw blades such as a circular saw blade, a straight saw blade, etc. may be used, which are not listed here, and can be used by simply modifying the bottom plate according to actual needs.

Further, the support assembly of the fifth to seventh embodiments may also adopt a structure in which the support assembly of the first embodiment has a base plate with an adjustable position, so that when the support assembly and the saw blade described in the above embodiments are used alone as accessory products, the support assembly can be adapted to a wider variety of saw blades by making the position of the base plate of the support assembly adjustable.

The person skilled in the art can appreciate that many variations are possible in the specific structure of the portable cutting machine of the present invention, but the main technical features of the portable cutting machine are the same as or similar to those of the present invention, and are all covered by the scope of the present invention.

Claims

1. A portable cutter comprising:

a housing;

a swing output shaft partially extending out of the housing, having an output shaft axis;

a motor housed in the housing;

a drive shaft driven for rotation by the motor, the drive shaft having a drive shaft axis;

a motion conversion mechanism that converts rotation of the drive shaft into swing of the swing output shaft;

the method is characterized in that: the axis of the output shaft and the axis of the driving shaft are arranged in parallel.

2. The portable cutter according to claim 1, characterized in that: the motion conversion mechanism comprises an eccentric part arranged on the driving shaft and a shifting fork matched with the eccentric part and fixedly arranged on the swinging output shaft, the eccentric part is provided with a central line eccentrically arranged relative to the axis of the driving shaft, and the central line is arranged in parallel with the axis of the output shaft.

3. The portable cutter according to claim 1, characterized in that: the swing frequency of the swing output shaft is more than 30000 times/minute.

4. The portable cutter according to claim 1, characterized in that: the shell comprises a motor accommodating part for accommodating the motor and a holding part for holding, and the holding part and the motor accommodating part are arranged separately.

5. The portable cutter according to claim 4, characterized in that: the whole of the holding part is elongated to form a longitudinal extending direction of the holding part, and the longitudinal extending direction of the holding part is perpendicular to the axis of the output shaft.

6. The portable cutter according to claim 5, characterized in that: the shell is also provided with a battery pack accommodating part which extends in the same direction as the holding part.