JPH11138333A - Hand cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hand cutter with a dust collector which has a good operability improving the peripheral structure of a dust pipe, as well as improving the dust collecting performance, reducing the width of the hand cutter to make it compact, and improving the weight ballance. SOLUTION: A power unit housing a driving source 1; a dust collecting unit 3 having a dust collecting fan 4a driven being connected to the output shaft 1a of the driving source 1; and a cutting head unit which is connected to the output shaft 1a of the driving source 1, and consists of a cutter blade 5 driven to rotate, a cutter head 25 to support the cutter blade 5 rotatable, and a safety cover 6 to cover the cutter blade 25; are provided to form the hand cutter consisting of three units, and a dust collecting fan and a dust suction port are arranged at the position lower than the line combining the axial core of the cutter blade and the output shaft of the driving source, and at the same time, the driving system of the cutter head and the dust collecting fan is composed as an independent layout.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hand cutter used for cutting secondary concrete products and the like, and more particularly to a hand cutter provided with a dust collecting device for preventing dust during work from scattering around.

[0002]

2. Description of the Related Art Hand cutters are U-shaped grooves buried in road gutters, fume pipes used as sewer pipes, secondary concrete products such as curbs on roads, bricks, asphalt paved roads, cast iron pipes for waterworks, and steel materials. It is widely used for cutting and the like. The dust is scattered around the cutting work of secondary concrete products, bricks and asphalt paved roads by this hand cutter, which is a problem in terms of the health of workers, especially in urban areas where there are many complaints due to dust. is there. In order to solve such a problem, recently, a hand cutter with a dust collector has been developed. As one example of the prior art of the hand cutter, utility model registration No. 2530503 will be described with reference to FIG. An opening 5 is provided in the safety cover 52 surrounding the cutter blade 51.
4 are provided. The opening 54 communicates with a suction port 57 of a dust suction device 56 via a pipe 55. Dust suction device 5
The exhaust pipe 59 communicates with the dust collection bag at the exhaust port 58 of FIG. The small pulley 61 is rotated by the output shaft of the engine 60. The rotation of the small pulley 61 is transmitted via a belt to rotate the large pulley, thereby rotating the fan 69. The rotation of the large pulley is transmitted via a belt to rotate the small pulley to rotate the cutter blade 51.

Japanese Patent Publication No. Hei 7-14570 will be described as two examples of the prior art of the hand cutter with reference to FIGS. In order to reduce the output rotation speed of the engine 110, the small pulley 97 of the engine output shaft and the pulley 98 of the shaft on the side of the blade 78 are connected to the large pulley of the composite pulley 99 through two large and one small composite pulleys 99. The belt 100 to be hung is hung on a small pulley 96 installed on the drive shaft 95 of the forced dust fan 89. Above the safety cover body 71 that covers the blade 78, a dust discharge device 80 is provided. A hole is formed in the side wall of the safety cover main body 71 to serve as a dust inlet 79 of the dust exhaust device 80. Inside the safety cover main body 71, a partition wall 82 having a slit that does not hinder the rotation of the blade 78 surrounds the dust inlet 79 and extends near the center of the blade 78 as a wall surface of the dust passage 81. The dust exhaust pipe 80a connected to the dust exhaust device 80 is disposed so as to extend rearward from above the safety cover main body 71.

[0004]

However, the hand cutter disclosed in Utility Model Registration No. 2530503 has the structure shown in FIG.
As shown in FIG. 7, the small pulley 61 is rotated by the output shaft of the engine 60, the rotation of the small pulley 61 is reduced by the large pulley via the belt, and then the fan 69 is rotated. Is difficult to raise,
For this reason, the dust absorption performance for preventing scattering of dust is poor. Further, the structure is such that the small pulley 61 is once decelerated by the large pulley, and then the small pulley 61 is driven via the large pulley to rotate the cutter blade 51, which is inefficient. The structure emphasizes the rotational driving of the cutter blade 51 on the attachment side, and does not have a structure for improving the dust absorbing performance. Further, according to the hand cutter of Utility Model Registration No. 25530503, (1) the fan rotation ratio depends on the rotation ratio of the cutter blade drive system, so that the fan rotation speed can be increased to improve fan performance. It is difficult to reduce the size of the dust absorption fan. (2) Since the suction port 57 on the upper part of the safety cover and the dust suction device 56 are communicated with each other by the pipe 55, it is not possible to compact the appearance and the pipe 55 comes into contact with the worker during the work. As a result, there is a possibility that the pipe 55 may be caught by something during the work and may be damaged, thus causing a problem in safety. (3) Since the entire width of the hand cutter is large and the eccentric weight is large instead of the compact, handling during work is not good.

As shown in FIGS. 18 to 20, the hand cutter disclosed in Japanese Patent Publication No. 7-14570 has a small pulley 97 for the engine output shaft and a large pulley 98 for the shaft on the blade 78 side.
The composite pulley 9 is connected via one composite pulley 99
The belt 100 which is hung on the large pulley 9 is hung on the small pulley 96 installed on the drive shaft 95 of the forced dust fan 89. For this reason, the structure of the dust fan 89 is complicated because the dust fan 89 is once decelerated by the large pulley from the small pulley 97 and then accelerated by the small pulley 96 via the large pulley to rotate the dust fan 89. In addition to the poor maintainability, it is difficult to increase the rotation speed of the fan, and it is not possible to improve the dust absorption performance and reduce the size of the fan. Further, a dust discharge device 80 is provided above the safety cover main body 71, and dust generated when cutting with the blade 78 passes through the dust discharge passage 81 of the safety cover main body 71, Since it is stored in a dust collecting bag (not shown) via the dust discharging pipe 90, the distance from the cutting position of the blade 78 to the dust discharging device 80 is long, and there is a lot of dust scattered around. Is poor, so the dust absorption performance is poor. Further, as shown in FIG. 18, when the top view of the hand cutter is viewed,
Since the fan 89 extends to the left, the visibility of the cutting edge of the blade 78 is impaired. Furthermore, a dust pipe 9
Since the arrangement of 0 is poor and the structure protrudes to the worker side, it becomes obstructive due to contact with the worker and the workability is poor. Further, since many parts such as the dust exhaust device 80 and the compound pulley 99 are integrated on the safety cover main body 71 side, the weight at the tip side of the hand cutter is heavy, and the weight balance is poor. Has become. Further, inside the safety cover main body 71, a partition wall 82 having a slit that does not hinder the rotation of the blade 78 surrounds the dust inlet 79 and extends as a wall surface of the dust passage 81 near the center of the blade 78 for safety. Since it is formed integrally with the cover main body 71, it is difficult to insert the blade 78 into the slit of the partition wall 82, and the assemblability is poor.

Further, according to the hand cutter disclosed in Japanese Patent Publication No. 7-14570, (1) the dust exhaust device 80 is provided on the side surface of the safety cover main body 71, so that the weight becomes unbalanced and the weight balance is poor. (2) Since dust is sucked in from the side of the safety cover main body 71, dust absorption efficiency is poor. (3) Dust exhaust device 8 near the left hand handle of the hand cutter
Since 0 is arranged, in order to secure clearance around the handle, the handle becomes large and the overall length becomes long, so that compactness cannot be achieved. (4) Since the dust removal device 80 is provided on the safety cover main body 71, the size of the cutter blade depends on the mounting position of the dust removal device and depends on the size of the cutter blade. In case, the safety cover body 71
Need to replace is not economical. (5) Since the rotation ratio of the fan depends on the rotation ratio of the blade 78, it is difficult to increase the rotation of the dust suction fan to improve the dust absorption performance.

The present invention focuses on the above-mentioned conventional problems, and improves the dust-absorbing performance, reduces the width of the hand cutter to make it compact, improves the weight balance, and improves the operability of the dust pipe. An object of the present invention is to provide a hand cutter with a dust device.

[0008]

To achieve the above object, a first invention of a hand cutter according to the present invention comprises a power unit accommodating a driving source such as an engine and a motor, and an output shaft of the driving source. A dust suction unit having a dust suction fan connected to and driven by a cutter, a cutter blade connected to an output shaft of a driving source and driven to rotate, a cutter head rotatably supporting the cutter blade, and a safety cover covering the cutter blade. And a head unit. According to the above configuration, the cutting head unit has the following operational effects by the three-unit structure in which the dust suction device and the drive system for driving the dust suction device are not provided. (1) The weight of the cutting head unit is reduced, the eccentric weight can be made closer to the position of the center of gravity of the entire cutter device, and an easy-to-handle hand cutter with excellent weight balance can be obtained. (2) Since the cutting head unit is independent and does not depend on the dust suction device, it can be achieved by changing the cutting head unit or changing only the cutter blade even for specifications with different cutter blade sizes (for example, 12 inches or 14 inches). it can. (3) The area around the cutting head unit is simple, there is no obstruction to the field of view, it is easy to check the cut part during work, safe and reliable work is possible, and there is enough space around the left handle. It can be provided and is a safe hand cutter with good handling. (4) Since the dust suction device is close to the power unit side, the drive system of the dust suction device is simple, and the drive ratio of the fan can be set freely, so that the fan speed can be easily set, the suction performance can be improved, and the hand cutter can be improved. The drive system for driving the dust suction fan and the drive system for driving the cutter blade are made independent by using a three-unit structure, and the output shaft of a drive source such as an engine or a motor is shared. Since the drive ratio does not depend on the drive ratio, the drive ratio of the dust suction fan can be appropriately set, so that the dust suction performance can be improved and the fan can be reduced in size. (5) In addition, the drive system for driving the dust suction fan and the drive system for driving the cutter blade are made independent by the three-unit structure of the hand cutter, so that two drive systems having different driving forces can be designed independently. The strength can be calculated according to each drive system, so that a structure without waste can be obtained. (6) The inspection and maintenance of the dust suction fan and the like can be easily performed simply by removing the dust suction unit.

According to a second aspect of the present invention, in the configuration of the first aspect, the power unit and the dust-absorbing unit are connected to each other, and the cutting head unit is connected to the dust-absorbing unit, or the power unit and the cutting head unit are connected to each other. And the power unit is connected to the dust suction unit. According to the above configuration, in addition to the function and effect of the first invention, by appropriately setting the configuration for connecting the three units of the power unit, the dust suction unit, and the cutting head unit, the hand cutter can be made compact, assembling, and maintenance can be performed. Performance can be improved.

A third invention is characterized in that, in the configuration of the first invention, the dust suction unit and the cutting head unit are detachable and the length is adjustable. According to the above configuration, in addition to the operation and effect of the first invention, assemblability and maintainability of the hand cutter are improved, and the total length can be adjusted. Therefore, by replacing the cutting head unit, a different cutter blade can be obtained. It is possible to easily cope with a hand cutter having a size, which is very economical.

According to a fourth aspect of the present invention, there is provided a drive source such as an engine or a motor, a dust suction device connected to an output shaft of the drive source for driving a dust suction fan to be driven, and a rotary drive connected to an output shaft of the drive source. In a hand cutter comprising a cutter blade, a cutter head for rotatably supporting the cutter blade, and a safety cover for covering the cutter blade, a dust suction device 4 for sucking dust at the time of cutting operation by the cutter blade is connected to a shaft of the cutter blade and a driving source. Are disposed below the line connecting the output shafts. According to the above configuration, since the dust suction device is disposed below the line connecting the axis of the cutter blade and the output shaft of the drive source, (1) routing of the dust pipe from the dust suction device to the dust bag becomes easy, The operability of the hand cutter is good because it does not approach the operator. (2) Since the dust suction fan can be installed below the power unit, the overall width of the hand cutter can be reduced, thereby improving workability in a narrow place. (3) Since the dust suction device is located at the lowest position of the hand cutter in a state where the hand cutter is gripped by both hands, eccentric weight is reduced, and handling with less fatigue due to operation is obtained. (4) The dust suction device can be directly connected to the dust suction port of the safety cover that sucks dust, so there is no need to connect the safety cover and the dust suction device with pipes as in the past, and the structure is simple and compact. Hand cutter. (5) Since the dust suction device is located below the hand cutter, there is nothing obstructing the field of view of the operator, and the visibility of the cutting edge of the blade is improved.

In a fifth aspect based on the first or fourth aspect, the dust-absorbing fan overlaps the drive belt at a position below the drive belt that drives the cutter blade from the drive source and when viewed from above the hand cutter. It is characterized in that it is arranged so as to make it closer. According to the above configuration, in addition to the functions and effects of the first or fourth invention, the entire width of the hand cutter can be further reduced and the hand cutter can be compactly assembled, so that the workability in a narrow place is improved and the hand cutter is easy to handle. It can be.

According to a sixth aspect of the present invention, in the configuration according to any one of the first to fifth aspects, a driving pulley coaxial with the output shaft of the driving source and spline-coupled, and a driving pulley And the dust suction fan is driven via a belt. According to the above configuration, since the dust suction unit formed as a unit accommodating the dust suction device is spline-coupled to the output shaft of the drive source, assemblability and maintainability are improved. In addition, the replacement of the driving belt of the cutter blade can be easily performed by simply removing the dust suction unit.

A seventh invention is characterized in that, in the structure according to any one of the first invention to the sixth invention, the driving belt of the dust suction fan of the dust suction device is adjustable from outside. According to the above configuration, the tension adjustment of the drive belt of the dust suction fan is facilitated, and the maintainability is improved.

According to an eighth aspect of the present invention, there is provided a hand cutter having a safety cover having a safety cover covering a part of an outer peripheral portion of a cutter blade and a slide guide housed in the safety cover according to a working posture at the time of cutting. The slide guide is characterized in that the slide guide is provided with a dust suction passage which rotates with respect to the safety cover and guides dust generated during cutting work by the cutter blade to a dust suction port provided in the safety cover. According to the above configuration, since the slide guide rotates with respect to the safety cover and is housed in the safety cover depending on the working posture, it is easy to change the cutting position when cutting a secondary concrete product or the like, thereby improving workability. Is improved. In addition, the slide guide is provided with a dust suction passage that rotates with respect to the safety cover and guides dust during cutting work by the cutter blade to a dust suction port provided in the safety cover, so that dust is not scattered. Therefore, by efficiently guiding the dust to the dust suction port, the dust is not scattered to the surroundings during the cutting operation by the hand cutter, so that the health problem of the worker and the complaint due to the dust in the city area are solved.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a hand cutter according to the present invention will be described below with reference to FIGS. The hand cutter 30 of the present invention includes a power unit that houses a driving source 1 such as an engine and a motor, and an output shaft 1 a of the driving source 1.
, A cutter blade 5 connected to the output shaft 1 a of the drive source 1, a cutter head 25 rotatably supporting the cutter blade 5, and a cutter blade 25 connected to the output shaft 1 a of the drive source 1. And a cutting head unit comprising safety covers 6 and 6c covering the unit 5. The dust suction device 4 includes a dust suction fan 4b and a driving device 2 for driving the dust suction fan 4b.
The dust storage unit 3 is referred to as a dust suction unit 3. First, FIG. 1 shows a side view of a hand cutter 30, and an output shaft (not shown) of a drive source 1 (hereinafter, referred to as a drive source 1) such as an engine or an electric motor sucks dust, which will be described in detail later. It is connected to a driving device 2 including a pulley and a belt for driving a dust suction device 4 including a dust suction fan. An output shaft (not shown) of the driving source 1 includes a pulley, a belt, and a gear, which will be described in detail later, and is connected to a driving device 40 that drives the cutter blade 5. The safety cover 6 is provided so as to cover the cutter blade 5. In the safety cover 6, a front guide 6n and a slide guide 6a are provided so as to be stowable. The dust suction device 4 composed of a dust suction fan, which will be described in detail later, is connected to a dust bag 35 that stores dust via a dust pipe 35A. Reference numerals 1A and 20 denote handles. The operator holds the handle 1A with the right hand and the handle 20 with the left hand so that the hand cutter can be easily handled.

A case 10 is detachably attached to the lower side of the drive source 1 shown in FIG. The output shaft 1a of the drive source 1 is inserted into an insertion hole provided in the case 10,
The coaxial 1a protrudes from the side of the case 10. As shown in FIG. 13, the output shaft 1a is connected to a pulley 7b for driving a dust suction device composed of a dust suction fan 4b and a pulley 7a for driving a cutter blade. A drive pulley 2 having a smaller diameter than the dust suction device drive pulley 7b is rotatably attached to the case 10 by a shaft 2a. The driving pulley 7b and the driving device 2 are wound around a belt 9.
Reference numeral 8 denotes an idler pulley for adjusting the tension of the belt. The driving device 2 is rotatably mounted by a dust suction fan 4b and a shaft 2a. The dust suction device 4 includes a dust suction fan 4b, a dust suction case 4f shown in FIG. 8, a dust suction port 4g, and a dust discharge port 4a shown in FIG.

The cutter blade 5 is rotatably mounted on a shaft 5a mounted on the cutter head 25. The driven pulley 11 has a shaft 11 attached to the cutter head 25.
a so as to be rotatable. A cutter blade driving pulley 7a connected to the output shaft 1a and a driven pulley 11 are wound around a belt 12. The driven pulley 11 drives a gear of a driving device 40 of the cutter blade 5 described later in detail.
The safety cover 6 is detachably or integrally formed with a cutter head 25 that rotatably supports the cutter blade 5 shown in FIG. The cutter head 25 and the case 10 are attached by stud bolts 15 and 16 shown in FIG.

A front guide 6n and a slide guide 6a are provided in a lower safety cover 6c integrally formed below the safety cover 6 shown in FIGS. 6b is a guide roller. The slide guide 6a shown in FIG. 3 is constantly urged in the lower right direction shown in the figure by a spring 6s, and uses a pin 6t at the tip of the front guide 6n as a rotation fulcrum. For this reason, when working by holding the handle 20 shown in FIG. 2 by hand, by pushing the hand cutter 30 in the direction of the guide roller 6b, the slide guide 6a is fixed to the safety cover 6 against the spring 6s. It can be stored along the bottom of the lower safety cover 6c. When a force is not applied in the direction of the guide roller 6b by changing the working posture of the hand cutter 30, the slide guide 6a is protruded from the lower safety cover 6c to the lower right by the spring 6s as shown in FIG. It has become. The front guide 6n is provided with a long hole 6h for enabling rotation. The lower safety cover 6c has a guide pin 6
m is fixed. The front guide 6n is a long hole 6h
A guide pin 6m is inserted into the shaft, and is constantly urged to the lower right by a spring 6g, and the pin 6q is used as a rotation fulcrum. Thus, when working with the handle 20 shown in FIG. 2 by hand, the hand guide 30 is added in the direction of the guide roller 6b to thereby provide the front guide 6n.
Can be housed in the lower safety cover 6c fixed to the safety cover 6 against the spring 6g.
When no force is applied in the direction of the guide roller 6b by changing the working posture of the hand cutter 30, the front guide 6n is protruded from the lower safety cover 6c to the lower right by the spring 6g as shown in FIG. It has become. The pins 6p and 6q serving as rotation fulcrums of the front guide 6n and the slide guide 6a shown in FIG. 3 are located near the shaft 5a of the cutter blade 5 on the side surface of the safety cover. The rotation fulcrum of the guide 6a may be the shaft 5a of the cutter blade 5.

By the action of the front guide 6n and the slide guide 6a, the cutting angle or the cutting position of the cutter blade 5 can be changed according to the working posture of the hand cutter 30, so that the workability is good. A guide roller 6d is rotatably attached to the slide guide 6a, and the guide roller 6d of the cover 6a is
The slide guide 6a is linearly movable along the bottom of the lower safety cover 6c, and slides within the range of the elongated hole 6h against the spring 6g to be housed in the lower cover 6c. ing. A dust stopper 6f is attached to the safety cover 6. This dust stopper 6f
Is provided with a slit which does not hinder the rotation of the cut plate 5, and the cutter blade 5 is rotatable in this slit. Also, this dust stopper 6f
Serves to prevent dust from scattering above the safety cover 6 and guides the dust to a dust suction port 6e provided in the safety cover 6. This dust stopper 6f
Is formed in a straight line and is provided detachably with respect to the safety cover 6, so that it is easy to insert the cutter blade into the slit of the dust stopper 6f and the assembling property is good.

As shown in FIG. 3, dust scattered at the time of cutting a concrete secondary product or the like is sucked from a dust suction port 4g of a dust suction case 4f by a rotary drive of a dust suction fan 4b by a cutter blade 5 described later in detail. It is stored in the dust bag 35 from the dust outlet 4a shown in FIGS. Thus, the dust pipe 3
5A is disposed below the drive source 1, so that the handling of the dust pipe 35A from the dust suction fan 4b is significantly improved as compared with the related art, and the cutting pipe 5A comes close to the body of the worker during cutting work and becomes obstructive. Alternatively, the visibility of the cutting edge of the cutter blade is not obstructed.

Next, the front guide 6n, slide guide 6a, dust suction port 6e, and dust suction device 4 will be described with reference to FIGS. FIG. 4 shows a left side view of the hand cutter. The dust suction device 4 includes an output shaft 1 a of the drive source 1.
And a line A connecting the shaft 5a of the cutter blade 5 to the axis of the cutter blade 5. As described above, by pushing the hand cutter 30 in the direction of the guide roller 6b, the front guide 6n and the slide guide 6a
Are stored in the lower safety cover 6c at the positions indicated by the dotted lines. FIG. 5 shows a state in which the front guide 6n and the slide guide 6a protrude from the lower safety cover 6c. FIG. 6 shows that the front guide 6n is in the X direction of the arrow and the slide guide 6a is in the Y direction of the arrow. It shows a state in which they are separately stored in the lower safety cover 6c. Thereby, the dust during the cutting operation is guided from the front guide 6n and the slide guide 6a to the dust suction port 6e. A dust suction device 4 including a dust suction fan is disposed near the dust suction port 6e. With this configuration, it is not necessary to connect the dust suction port and the dust suction device with a pipe as in the related art as described above, and the dust suction device can be directly connected to the dust suction port that sucks the dust of the safety cover. In addition, a compact and simple hand cutter can be provided.

FIG. 7 shows another embodiment of the hand cutter. Components denoted by the same reference numerals as those in FIGS. 1 to 6 have the same functions, and thus description thereof is omitted here. According to FIG.
The dust suction device is installed at a predetermined place in the work site, and the hand cutter is provided with a dust port 35B for sucking dust guided from the front guide 6n and the slide guide 6a in the lower safety cover 6c. The dust sucked from the dust port 35B is sent to a dust suction device (not shown) via a dust pipe 35c. As a result, the weight of the hand cutter can be reduced, so that the hand cutter can be easily handled during the cutting operation. In this case as well, the dust pipe 35c is located below the driving source 1 as described above, so that the hand cutter has a good weight balance and is compact and easy to handle.

FIG. 8 as viewed in the direction Z in FIG. 2 will be described with reference to FIGS. Coupling member 1 composed of a coupling and a bearing coupled to spline 1c to output shaft 1a of drive source 1
Drive pulleys 7a and 7b are rotatably attached to the shaft 5 and the shaft 1b connected to the joint member 15. A dust suction fan 4b disposed below the drive pulleys 7a and 7b;
The drive device 2 is rotatably mounted on a shaft 2a. 4d is a bearing for supporting the shaft 2a. Dust suction device 4
Is composed of a dust suction fan 4b, a dust suction case 4f, a dust suction port 4g, and a dust discharge port 4a shown in FIG. The drive pulley 7b and the drive device 2 shown in FIG. As a result, the rotation output of the output shaft 1a of the drive source 1 is transmitted to the drive device 2 via the drive pulley 7b and the belt 9, whereby the dust suction fan 4b is driven to rotate.

Next, FIG. 9 shows a state in which the driving source 1, the driving device 2, and the dust suction device 4 are integrally assembled. 1 to 3 have the same functions, and a description thereof will be omitted. A handle 20 is attached to the power unit that houses the drive source 1. A leg 22 is fixed to the lower portion of the power unit and the case 10. A guide groove 10 c for guiding the belt 12 is formed in the case 10. An adjustment plate 10 a for adjusting the tension of the belt 9 is attached to the case 10, and the plate 10 a is provided with a long hole 10 b that allows the belt adjustment pulley 8 to move. As shown in FIG.
Work with the foot, and leg 2 when not working
2 is placed on the ground or floor to support the weight of the hand cutter.

FIG. 10 shows a state in which the cutter blade 5, the safety cover 6, the slide guide 6a and the cutter head 25 are integrally assembled. 1 to 3 have the same functions, and a description thereof will be omitted. The safety cover 6 and the cutter head 25 are detachably or integrally formed. Stud bolts 15 and 16 for attaching the case 10 shown in FIG. 2 are attached to the cutter head 25. FIG.
Is formed in a U-shape. The dust at the time of cutting by the cutter blade 5 is guided from the slide guide 6a to the dust suction port 4g shown in FIG. 8 through the lower safety cover 6c and the dust suction port 6e. FIG. 11 shows a state in which the slide guide 6a is housed in the lower safety cover 6c, and FIG.
Shows a state in which the slide guide 6a shown in FIG. 6 is urged by the spring 6g and protrudes outward from the lower cover 6c.

Next, a driving device for a hand cutter according to the present invention will be described with reference to FIGS. FIG.
FIG. 14 shows a power transmission system of the entire hand cutter represented by a symbol. The output shaft 1a of the drive source 1 shown in FIG. 13 is connected to the drive pulleys 7a and 7b.
The driving pulley 7a includes a driven pulley 11 and a belt 12
It is wound by. The power output from the output shaft 1a is transmitted from the driving pulley 7a to the driven pulley 11 via the belt 12. This driven pulley 11
The 1st gear 11b shown in FIG. 14 of the P section detailed view of FIG. 13 is driven. The first gear 11 meshes with the second gear 11c to drive the same gear 11c. This second gear 11c
Engages with the third gear 11d to drive the gear 11d. The third gear 11d meshes with the fourth gear 11e to drive the same. This fourth gear 11e
Drives the cutter blade 5 with the shaft 5a as a rotation fulcrum.
Can be driven to rotate.

FIG. 15 shows an arrangement of a driving pulley and a driven pulley. An axis A connecting the center of the output shaft 1a and the center of the shaft 11a of the driven pulley 11;
The angle formed between the center of a and the axis B connecting the center of the shaft 2a of the driving device 2 is set to a predetermined angle α1. The center of the output shaft 1a and the center of the shaft 2a of the driving device 2 are set to be separated by a predetermined distance L1. As a result, the driving device 2 is disposed at an appropriate position, the weight balance of the hand cutter is good, and the structure is simplified, so that the entire hand cutter becomes compact.

FIG. 16 shows a power transmission system of the cutter blade described with reference to FIGS. In the driving device 40 of the cutter blade 5, the output shaft 1a of the driving source 1 is connected to the driving pulley 7a. The driven pulley 11 is wound around a belt 12. As a result, the power output from the output shaft 1a is transmitted from the driving pulley 7a to the driven pulley 11 via the belt 12. The driven pulley 11 drives the small-diameter first gear 11b. This small diameter first gear 11 meshes with the large diameter second gear 11c to drive the same gear 11c. The large-diameter second gear 11c meshes with the small-diameter third gear 11d to drive the same gear 11d. The small-diameter third gear 11d meshes with the large-diameter fourth gear 11e to drive the same gear 11e. By driving the fourth gear 11e having a large diameter, the shaft 5 is driven.
The cutter blade 5 is driven to rotate via the a. As described above, the rotation speed of the output shaft 1 a
The speed is reduced by each of the 0 gears 11b, 11c, 11d, and 11e, and the cutter blade 5 is driven by a predetermined rotation. Drive pulleys 7a and 7b are rotatably attached to a coupling connected to the output shaft 1a by a spline 1c, a joint member 15 composed of a bearing, and a shaft 1b connected to the joint member 15.

As described above, in the hand cutter of the present invention, in order to solve the above-mentioned conventional problems, the cutting head unit does not include a dust suction device and a drive system for driving the dust suction device. The following operation and effect can be obtained by the three-unit structure described above. The weight of the cutting head unit is reduced, the eccentric weight can be made closer to the position of the center of gravity of the entire cutter device, and an easy-to-handle hand cutter with excellent weight balance can be obtained.

Since the cutting head unit is independent and does not depend on the dust suction device, it can be achieved by changing the cutting head unit or changing only the cutter blade even for specifications having different cutter blade sizes (for example, 12 inches or 14 inches). it can.

The surroundings of the cutting head unit are simplified, there is no obstruction to the field of view, and it is easy to confirm the cut portion at the time of work, and safe and reliable work is possible. It can be provided and is a safe hand cutter with good handling.

Since the dust suction device is close to the power unit side,
The drive system of the dust suction device is simple and the drive ratio of the fan can be set freely, so the fan rotation speed can be easily set, the suction performance can be improved, and the hand cutter has a three-unit structure to drive the dust suction fan. And the drive system that drives the cutter blade is independent,
By sharing the output shaft of a drive source such as an engine or a motor, the drive ratio of the dust suction fan can be set as appropriate because the drive ratio does not depend on the drive system of the cutter blade. The size can be reduced.

Since the driving system for driving the dust suction fan and the driving system for driving the cutter blade are made independent by the three-unit structure of the hand cutter, two driving systems having different driving forces can be designed independently. It is sufficient to calculate the strength in accordance with the drive system of the above, so that a structure without waste can be obtained.

The inspection and maintenance of the dust suction fan and the like can be easily performed simply by removing the dust suction unit 3.

By appropriately setting the structure for connecting the three units of the power unit, the dust suction unit, and the cutting head unit, the hand cutter can be made compact, and the assembling and maintenance can be improved.

Since the assemblability and maintainability of the hand cutter are improved and the overall length can be adjusted, it is possible to easily cope with hand cutters having different cutter blade sizes by replacing the cutting head unit. Is very economical.

The handling of the dust pipe from the dust suction device to the dust bag becomes easy and the operability of the hand cutter is good because it does not approach the operator.

Since the dust suction fan can be installed below the power unit, the overall width of the hand cutter can be reduced, so that workability in a narrow place is improved.

Since the dust suction device is located at the lowermost position of the hand cutter in a state where the hand cutter is gripped by both hands, eccentric weight is reduced, and handling with less fatigue due to operation can be obtained.

Since the dust suction device can directly communicate with the dust suction port of the safety cover for sucking dust, there is no need to connect the safety cover and the dust suction device with a pipe as in the prior art, and the structure is simple and compact. Hand cutter.

Since the dust suction device is located below the hand cutter, there is nothing obstructing the operator's field of view, and the visibility of the blade of the blade is improved.

Since the entire width of the hand cutter can be further reduced to make it compact, a hand cutter that is easy to handle can be obtained.

[0044] Since the dust suction unit formed as a unit accommodating the dust suction device is spline-coupled to the output shaft of the drive source, assemblability and maintainability are improved. In addition, the replacement of the driving belt of the cutter blade can be easily performed by simply removing the dust suction unit.

Since the drive belt of the dust suction fan of the dust suction device can be adjusted from the outside, the adjustment of the tension of the drive belt of the dust suction fan is facilitated and the maintainability is improved.

Since the slide guide rotates with respect to the safety cover and is housed in the safety cover depending on the working posture, it is easy to change the cutting position when cutting a secondary concrete product or the like, thereby improving workability. improves. In addition, the slide guide is provided with a dust suction passage that rotates with respect to the safety cover and guides dust during cutting work by the cutter blade to a dust suction port provided in the safety cover, so that dust is not scattered. Therefore, by efficiently guiding the dust to the dust suction port, the dust is not scattered to the surroundings during the cutting operation by the hand cutter, so that the health problem of the worker and the complaint due to the dust in the city area are solved.

Although the present invention has been described as a hand cutter for cutting secondary concrete products and the like, it goes without saying that various cutter blades can be prepared and applied to a hand cutter for cutting metal or wood. No.

[Brief description of the drawings]

FIG. 1 is a side view in which a dust bag is connected to a hand cutter of the present invention.

FIG. 2 is a right side view of the hand cutter.

FIG. 3 is an explanatory view of a slide guide that slides on a safety cover.

FIG. 4 is a left side view of the hand cutter.

FIG. 5 is a diagram illustrating a state where the front guide and the slide guide protrude from the lower safety cover.

FIG. 6 is a diagram illustrating a state where the front guide and the slide guide are stored in a lower safety cover.

FIG. 7 is a diagram illustrating another example of a hand cutter.

FIG. 8 is a Z view of FIG. 2;

FIG. 9 is a view for explaining a state in which the drive source, the drive device, and the dust suction device are integrally assembled.

FIG. 10 is an explanatory view of the safety cover with an exterior cover attached thereto.

FIG. 11 is a diagram illustrating a state in which a slide guide is stored in a lower safety cover.

FIG. 12 is a view for explaining a state in which the slide guide is biased by a spring and projects outward with respect to the lower safety cover.

FIG. 13 is a diagram illustrating a power transmission sequence of the hand cutter using symbol symbols.

FIG. 14 is a detailed view of a part P in FIG. 9;

FIG. 15 is a diagram illustrating a mounting angle and a mounting position with respect to a driving source, a driving pulley, a driven pulley, and a driving device.

FIG. 16 is an explanatory view of each gear for transmitting power of the hand cutter.

FIG. 17 is a side view of a conventional example of a hand cutter.

FIG. 18 is a top view of two conventional hand cutters.

FIG. 19 is an explanatory diagram of a drive system of the hand cutter of the two examples.

FIG. 20 is an explanatory view of two examples of the safety cover.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Driving source, 2 ... Dust suction fan driving device, 4 ... Dust suction device, 4b ... Dust suction fan, 5 ... Cutter blade, 6 ... Safety cover, 6a ... Slide guide, 6c ... Lower safety cover, 6n ... Front guide, 7a , 7b ... drive pulley, 9, 12 ... belt, 11 ... driven pulley, 40 ...
Driving device for cutter blade.

Claims (8)

[Claims] A power unit that houses a drive source such as an engine and a motor; a dust suction unit that has a dust suction fan that is connected to and driven by an output shaft of the drive source;
A hand cutter having a three-unit configuration including a cutter blade that is driven to rotate, a cutter head that rotatably supports the cutter blade, and a cutting head unit that includes a safety cover that covers the cutter blade. 2. The power unit and the dust suction unit are connected, and the cutting head unit is connected to the dust suction unit, or the power unit and the cutting head unit are connected,
2. The hand cutter according to claim 1, wherein the dust suction unit is connected to the power unit. 3. The hand cutter according to claim 1, wherein the dust suction unit and the cutting head unit are detachable and the length is adjustable. 4. A drive source such as an engine or a motor, a dust suction device connected to an output shaft of the drive source to drive a driven dust suction fan, and a cutter connected to an output shaft of the drive source and driven to rotate. In a hand cutter consisting of a blade, a cutter head that rotationally supports a cutter head that rotationally supports the cutter blade, and a safety cover that covers the cutter blade, a dust suction device that sucks in dust during cutting work by the cutter blade is driven with the axis of the cutter blade. A hand cutter disposed below a line connecting an output shaft of a source. 5. The dust suction fan is disposed at a position below a drive belt for driving a cutter blade from a drive source and is superposed on the drive belt when viewed from above the hand cutter. 4. The hand cutter according to 4. 6. A driving pulley which is concentric with an output shaft of a driving source and is spline-coupled, and wherein a dust suction fan is driven from the driving pulley via a belt. 6. The hand cutter according to any one of claims 1 to 5. 7. The driving belt of the dust suction fan of the dust suction device is adjustable from outside.
The hand cutter according to any one of the above. 8. A hand cutter having a safety cover having a safety cover covering a part of an outer peripheral portion of a cutter blade and a slide guide stored in the safety cover according to a working posture at the time of cutting. Rotates with respect to the safety cover, and
A hand cutter having a dust suction passage for guiding dust generated during cutting work by a cutter blade to a dust suction port provided in a safety cover.