Cutting work machine

Abstract

To realize a cutting work machine capable of supporting a plate-like material.SOLUTION: A knife cutter 1 includes: a housing which houses a motor; a cutting blade 18 which is driven by the motor; a first support part 50 provided at the housing; and a second support part 60 which is provided at the housing and separated from the first support part 50. A surface c1 of a cutting piece C is placed in contact with the first support part 50 and a rear surface c2, which is opposite to the surface c1, of the cutting piece C is placed in contact with the second support part 60 to support the cutting piece C.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a cutting work machine suitably used for cutting plywood, gypsum board, etc.

Background Art

[0002] As one of the cutting work machines, there is known a cutting work machine having a cutting blade reciprocally driven by a motor and used for cutting plywood, gypsum board, etc. (see Patent Document 1). This type of cutting work machine is sometimes called a "knife cutter" or a "board cutter". Also, as another one of the cutting work machines, there is known a cutting work machine having a cutting blade rotationally driven by a motor. This type of cutting work machine is also used for cutting plywood, gypsum board, etc.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The modes of work using a cutting work machine are diverse. Specifically, the object to be cut by the cutting work machine (for example, plywood, gypsum board, etc.) may be at a low place (such as the floor or a workbench) or at a high place (such as the ceiling). For example, in order to provide an air conditioner installation opening or an inspection opening in the ceiling, a part of the ceiling board may be cut using a cutting work machine to make a hole in the ceiling. When cutting a part of the ceiling board with a cutting work machine, it is necessary to support a part of the cut ceiling board (plate-shaped cut piece) to prevent it from falling.

[0005] However, the right hand or left hand of the operator is occupied for holding the cutting work machine. Therefore, the operator has to support the cut piece with one hand, and it has been difficult to support the cut piece in a stable state.

[0006] An object of the present invention is to provide a cutting work machine capable of supporting a plate-like body.

Means for Solving the Problems

[0007] The cutting work machine includes a housing that houses a motor, a cutting blade driven by the motor, a first support portion provided on the housing, and a second support portion provided on the housing and spaced apart from the first support portion. By bringing the first surface of the plate-like body into contact with the first support portion and bringing the second surface of the plate-like body on the side opposite to the first surface into contact with the second support portion, the plate-like body can be supported.

Effects of the Invention

[0008] According to the present invention, a cutting work machine capable of supporting a plate-like material is realized.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Mode for Carrying Out the Invention

[0010] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. FIGS. 1 and 2 show a knife cutter 1 which is an example of a cutting work machine to which the present invention is applied. The illustrated knife cutter 1 has a housing 10, a handle 20, a base 30, and a dust collection case 40, and is suitable for cutting plate materials such as plywood and gypsum board.

[0011] The housing 10 includes a substantially cylindrical motor housing part 11 and a base support part 12 that supports the base 30. The motor housing part 11 and the base support part 12 are integrally formed of a resin material. That is, a part of the housing 10 is formed by the motor housing part 11, and the other part of the housing 10 is formed by the base support part 12. Further, the housing 10 is composed of a first housing member 10R that forms half of the motor housing part 11 and the base support part 12, and a second housing member 10L that forms the remaining half of the motor housing part 11 and the base support part 12. The first housing member 10R and the second housing member 10L are fixed to each other in a butted state to form the housing 10.

[0012] The dust collection case 40 is provided at one longitudinal end side of the motor housing portion 11, and has a box-shaped appearance with its longitudinal direction being orthogonal to the longitudinal direction of the motor housing portion 11. In the following description, the longitudinal direction of the motor housing portion 11 is defined as the front-rear direction, the side where the dust collection case 40 is provided is the front, and the side opposite to the side where the dust collection case 40 is provided is the rear. Also, the longitudinal direction of the dust collection case 40 is defined as the up-down direction, the side where the base 30 is provided is the upper side, and the side where the handle 20 is provided is the lower side. Further, a third direction orthogonal to the front-rear direction and the up-down direction is defined as the left-right direction. As is clear from FIG. 1, the longitudinal direction of the motor housing portion 11 coincides with the longitudinal direction of the base 30. That is, the longitudinal direction of the base 30 is also the front-rear direction.

[0013] According to the above definitions, the handle 20 is provided below the housing 10, the base 30 is provided above the housing 10, and the dust collection case 40 is provided in front of the housing 10. Also, the first housing member 10R forms the right half of the housing 10, and the second housing member 10L forms the left half of the housing 10.

[0014] As shown in FIG. 3, the motor 13 is housed in the motor housing portion 11 of the housing 10. In addition to the motor 13, a speed reduction mechanism, a conversion mechanism, etc. are housed in the housing 10. The motor 13 is an electric motor powered by a battery (for example, a lithium ion battery) 14 mounted on the lower end of the handle 20. The motor 13 is a brushless motor including a motor housing in which a rotor and a stator are housed, and an output shaft fixed to the rotor and rotating integrally with the rotor. The output shaft is rotatably supported by a bearing, and a small-diameter bevel gear 15a is provided at the tip of the output shaft.

[0015] The small-diameter bevel gear 15a meshes with a large-diameter bevel gear 15b that rotates about a straight line extending in a direction intersecting the output shaft. The small-diameter bevel gear 15a and the large-diameter bevel gear 15b constitute a speed reduction mechanism that reduces the rotational speed of the output shaft of the motor 13 and increases the torque.

[0016] An eccentric cam is provided on a support shaft on which a large-diameter bevel gear 15b is provided. The eccentric cam rotates about an axis that is a straight line extending in a direction intersecting the output shaft of the motor 13, just like the large-diameter bevel gear 15b. However, the eccentric cam is eccentric with respect to the large-diameter bevel gear 15b.

[0017] Inside the housing 10, a mounting rod 16 that is substantially L-shaped in a side view is provided. The mounting rod 16 is supported by a swing shaft 17 so as to be movable vertically and longitudinally. The lower part of the mounting rod 16 is engaged with the eccentric cam, and the upper part of the mounting rod 16 is connected to a cutting blade 18. The mounting rod 16 engaged with the eccentric cam performs a periodic motion as the eccentric cam rotates. Specifically, the mounting rod 16 reciprocates periodically in the vertical and longitudinal directions as the eccentric cam rotates. The cutting blade 18 connected to the mounting rod 16 operates according to the periodic motion of the mounting rod 16 and cuts an object such as a plate material. In this way, a conversion mechanism is constituted by the eccentric cam and the mounting rod 16 to convert the rotational motion of the output shaft of the motor 13 into the reciprocating motion (swing) of the cutting blade 18.

[0018] When a switch 21 provided at the upper end of the handle 20 is operated, power is supplied to the motor 13, and the output shaft of the motor 13 rotates. As described above, the rotational motion of the output shaft of the motor 13 is decelerated by a speed reduction mechanism (small-diameter bevel gear 15a and large-diameter bevel gear 15b) and converted into the reciprocating motion of the cutting blade 18 by a conversion mechanism (eccentric cam and mounting rod 16). The user holds the handle 20 with the right or left hand and operates the switch 21 with the index finger of the hand holding the handle 20. For example, the user holds the handle 20 with the right hand and moves the knife cutter 1 from the rear to the front while operating the switch 21 with the index finger of the right hand. That is, the knife cutter 1 is pulled forward.

[0019] Refer to FIGS. 1 and 2 again. The base 30 has a substantially rectangular shape with the longitudinal direction being the long side. The base 30 has a two-layer structure including a main body portion 31 fixed to the housing 10 (base support portion 12) and a cover portion 32 laminated on the main body portion 31. The main body portion 31 is provided with a connection portion 35 (FIG. 12(a)) in which metal is inserted to enhance rigidity. The main body portion 31 is fixed to the housing 10 by screws inserted through through-holes provided in the connection portion 35. The cover portion 32 is detachable from the main body portion 31 fixed to the housing 10. One surface of the cover portion 32 attached to the main body portion 31 (the other surface opposite to the surface facing the main body portion 31) forms a contact surface 33 that is applied to the surface of the object when cutting the object.

[0020] The base 30 straddles the housing 10 and the dust collection case 40. Specifically, the rear of the base 30 overlaps with the upper part of the housing 10 (base support portion 12), and the front of the base 30 overlaps with the upper part of the dust collection case 40.

[0021] As shown in FIG. 3, the base 30 is provided with an opening 34 communicating with the dust collection case 40. The cutting blade 18 penetrates through the opening 34, and a part of the cutting blade 18 protrudes from the contact surface 33. When the cutting blade 18 reciprocates (oscillates) with the contact surface 33 applied to the surface of the object, the object is cut by the protruding portion of the cutting blade 18 protruding from the contact surface 33.

[0022] In addition, markers 36 (FIG. 13) such as triangular protrusions and V-shaped grooves are provided at the front and rear of the base 30 respectively. On the other hand, the cutting blade 18 is arranged on an imaginary straight line connecting the front and rear markers 36. Therefore, by aligning the ink lines and other cutting lines on the object with the markers 36, the object can be cut along the cutting line.

[0023] When the object to which the joint surface 33 is applied is cut by the cutting blade 18, dust is generated. The dust generated along with the cutting is collected in the dust collection case 40 through the opening 34. In other words, the dust collection case 40 collects the dust generated along with the cutting of the object through the opening 34 provided in the base 30, and prevents or reduces the scattering to the surroundings.

[0024] The dust collection case 40 is formed of a transparent or translucent resin (for example, polycarbonate). Therefore, the presence or absence and amount of dust in the dust collection case 40 can be visually confirmed. Further, when a pair of buttons 41 provided on both side surfaces of the dust collection case 40 are pushed in a direction approaching each other, the fixing of the dust collection case 40 to the housing 10 is released. Therefore, the dust collection case 40 can be separated from the housing 10 as needed, and the dust accumulated in the dust collection case 40 can be discarded.

[0025] As shown in FIGS. 1 and 2, the housing 10 is provided with a first support portion 50 and a second support portion 60. The first support portion 50 and the second support portion 60 are provided at different positions on the housing 10. Specifically, the first support portion 50 is provided in the motor housing portion 11, and the second support portion 60 is provided in the base support portion 12. More specifically, the first support portion 50 is provided on the upper surface of the rear end of the motor housing portion 11. On the other hand, the second support portion 60 is provided on the lower surface of the base support portion 12. As a result, the first support portion 50 and the second support portion 60 are spaced apart vertically and also spaced apart front and rear.

[0026] As shown in FIG. 1, the base support portion 12 extends from the front to the rear above the motor housing portion 11. That is, the base support portion 12 projects like an eaves above the motor housing portion 11. However, the rear end 12e of the base support portion 12 does not reach the rear end 30e of the base 30. In other words, the rear end 12e of the base support portion 12 is located in front of the rear end 30e of the base 30.

[0027] As a result of the base support portion 12 protruding above the motor housing portion 11, a substantially U-shaped space (insertion space 70) is formed between the housing 10 and the base 30 in a side view. In other words, the motor housing portion 11 and the base support portion 12 form a substantially U-shaped insertion space 70 between the housing 10 and the base 30 in a side view. And, the upper surface of the motor housing portion 11 where the first support portion 50 is provided corresponds to the lower surface (bottom surface) of the insertion space 70, and the lower surface of the base support portion 12 where the second support portion 60 is provided corresponds to the upper surface (ceiling surface) of the insertion space 70.

[0028] As described above, the first support portion 50 and the second support portion 60 are provided at different positions on the housing 10 and are spaced apart from each other in the vertical direction and the front-rear direction. However, the first support portion 50 and the second support portion 60 are common in that they are provided on the housing 10. For this reason, the first support portion 50 and the second support portion 60 are located between the handle 20 provided below the housing 10 and the base 30 provided above the housing 10 in the entire knife cutter 1. Similarly, the insertion space 70 is located between the handle 20 provided below the housing 10 and the base 30 provided above the housing 10 in the entire knife cutter 1. That is, the first support portion 50, the second support portion 60, and the insertion space 70 do not cause an increase in the size of the knife cutter 1 (particularly, an increase in size in the vertical direction).

[0029] Here, at least one of the first support portion 50 and the second support portion 60 is preferably made of rubber. Also, at least one of the first support portion 50 and the second support portion 60 preferably includes an anti-slip member. The first support portion 50 and the second support portion 60 in the present embodiment are formed of rubber members separate from the housing 10. That is, in the present embodiment, both the first support portion 50 and the second support portion 60 are made of rubber. Further, in the present embodiment, the first support portion 50 itself is an anti-slip member, and the second support portion 60 itself is an anti-slip member. In the following description, the rubber member as the first support portion 50 may be referred to as "rubber member 50a", and the rubber member as the second support portion 60 may be referred to as "rubber member 60a".

[0030] As shown in FIGS. 2 and 3, the rubber member 50a and the rubber member 60a are sandwiched and fixed between the first housing member 10R and the second housing member 10L.

[0031] The rubber member 50a has a block-shaped outer shape as a whole. A part of the rubber member 50a is sandwiched between the first housing member 10R and the second housing member 10L that are butted against each other. That is, a part of the rubber member 50a is inside the housing 10 (motor housing portion 11), and another part of the rubber member 50a is outside the housing 10 (motor housing portion 11). And the first support portion 50 is formed by a part of the rubber member 50a exposed outside the housing 10 (motor housing portion 11).

[0032] More specifically, a screw boss protruding inside the second housing member 10L is inserted into a through hole formed in the rubber member 50a. On the other hand, a screw inserted into a screw hole formed in the first housing member 10R is coupled to the screw boss that penetrates the rubber member 50a. As a result, the first housing member 10R and the second housing member 10L are fixed to each other by screws, and the rubber member 50a is sandwiched and fixed between the first housing member 10R and the second housing member 10L.

[0033] As shown in FIGS. 2 and 3, a part of the rubber member 60a is housed inside the housing 10 (base support portion 12), and the other part of the rubber member 50a is exposed outside the housing 10 (base support portion 12). And a second support portion 60 is formed by a part of the rubber member 60a exposed outside the housing 10 (base support portion 12).

[0034] In addition, a part (exposed portion) of the rubber member 50a forming the first support portion 50 is smaller than a part (exposed portion) of the rubber member 60a forming the second support portion 60. Further, the exposed portion of the rubber member 50a forming the first support portion 50 is flat or substantially flat, while the exposed portion of the rubber member 60a forming the second support portion 60 has an uneven structure (see FIG. 2) in which a plurality of concave portions and convex portions are arranged alternately. As a result, the surface of the first support portion 50 has a smaller frictional resistance than the surface of the second support portion 60. Also, the second support portion 60 is more likely to be crushed than the first support portion 50.

[0035] Next, with reference to FIGS. 4 to 7, an example of use of the knife cutter 1 will be described. Here, it is assumed that a part of the ceiling board A is cut using the knife cutter 1 to form an opening B in the ceiling board A. Also, it is assumed that the user holds the handle 20 of the knife cutter 1 with the right hand and performs the cutting operation.

[0036] As shown in FIG. 4, a part of the ceiling board A is cut out in a rectangle using the knife cutter 1. Specifically, while applying the contact surface 33 of the base 30 to the surface of the ceiling board A and moving the knife cutter 1 forward (in the direction of the arrow) while driving the cutting blade 18, a linear cut is formed in the ceiling board A. Such cutting operations are repeated a plurality of times to form four continuous cuts in the ceiling board A. At this time, the dust generated during cutting is collected in the dust collection case 40.

[0037] When the cutting process is completed, as shown in FIG. 5, a part of the ceiling board A is cut out in a rectangle, and a rectangular opening B is formed in the ceiling board A. At the same time, a part of the ceiling board A is separated from the ceiling board A, and a rectangular plate-like body C is formed. In the following description, the plate-like body C separated from the ceiling board A is referred to as the "cut piece C".

[0038] At the same time as the end of the cutting process, the cut piece C may fall due to its own weight. Therefore, at the end of the cutting process, before the four cuts are completely connected, the cut piece C is supported to prevent the cut piece C from falling. For example, while continuing the cutting operation, support the cut piece C from below with the left hand.

[0039] After that, while supporting the cut piece C with the left hand, place an arbitrary portion of the cut piece C on the first support portion 50 of the knife cutter 1. That is, an arbitrary portion of the cut piece C is received by the knife cutter 1. As a result, the first surface (front surface) c1 of the cut piece C abuts against the first support portion 50 of the knife cutter 1.

[0040] Next, as shown in FIG. 6, while suppressing the movement of the cut piece C with the left hand, move the knife cutter 1 backward (in the direction of the arrow). Then, as shown in FIG. 7, a part of the cut piece C is inserted between the first support portion 50 and the second support portion 60. In other words, a part of the cut piece C is inserted into the insertion space 70. At this time, the first support portion 50 slides on the surface c1 of the cut piece C.

[0041] As will be described later, finally, both the first support portion 50 and the second support portion 60 abut against the cut piece C. However, due to the size relationship between the first support portion 50 and the second support portion 60, the area where the second support portion 60 abuts against the cut piece C is larger than the area where the first support portion 50 abuts against the cut piece C. In other words, the area where the first support portion 50 abuts against the cut piece C is smaller than the area where the second support portion 60 abuts against the cut piece C. Further, the second support portion 60 has an uneven structure, while the first support portion 50 is flat or substantially flat. As a result, the frictional resistance between the first support portion 50 and the cut piece C is smaller than the frictional resistance between the second support portion 60 and the cut piece C. Therefore, the first support portion 50 can slide more smoothly on the cut piece C than the second support portion 60.

[0042] Thereafter, release or loosen the support of the cut piece C by the left hand. Then, the surface c1 of the cut piece C is pressed against the first support portion 50 by the weight of the cut piece C. As a result, a force (moment) is generated to rotate the cut piece C with the first support portion 50 as a fulcrum, and the second surface (back surface) c2 of the cut piece C on the side opposite to the surface c1 is pressed against the second support portion 60. That is, the surface c1 of the cut piece C is brought into contact (pressed) with the first support portion 50, and the back surface c2 of the cut piece C is brought into contact (pressed) with the second support portion 60. As a result, the user can support one side of the cut piece C with the right hand via the knife cutter 1 and support the other side of the cut piece C with the left hand. That is, the user can support two different positions of the cut piece C. However, when the cut piece C is small or light, etc., the support of the cut piece C by the left hand can be completely released, and the cut piece C can be supported only by the right hand (knife cutter 1). In any case, the user can support the cut piece C with the knife cutter 1.

[0043] Here, the second support portion 60 against which the back surface c2 of the cut piece C is pressed is more easily crushed than the first support portion 50. Therefore, the second support portion 60 is greatly crushed (greatly deformed) by the load received from the cut piece C and presses more strongly against the back surface c2 of the cut piece C. That is, the surface pressure applied to the contact surface between the cut piece C and the second support portion 60 increases.

[0044] In short, the surface c1 of the cut piece C is pressed against the first support portion 50 that is flat and harder than the second support portion 60, while the back surface c2 of the cut piece C has irregularities and is pressed against the second support portion 60 that is softer than the first support portion 50. As a result, a part of the cut piece C inserted into the insertion space 70 is supported in a very stable state. Furthermore, the first support portion 50 and the second support portion 60 that sandwich the cut piece C from above and below and have an anti-slip function suppress the movement of the cut piece C in the front-rear direction and the left-right direction where they are in contact, so that a part of the cut piece C is more stably supported.

[0045] The force (moment) that attempts to rotate the cutting piece C with the first support portion 50 as a fulcrum may be applied or added by the user to the cutting piece C. For example, when the length of the cutting piece C protruding rearward from the first support portion 50 is short, sufficient moment may not be obtained only by the weight of the cutting piece C. In such a case, the user may apply a force to the cutting piece C in order to obtain sufficient moment.

[0046] As described above, the user supports the cutting piece C with the right hand via the knife cutter 1. At this time, the user is gripping the handle 20 of the knife cutter 1 with the right hand. That is, the user supports the weights of the knife cutter 1 and the cutting piece C with the right hand gripping the handle 20. Therefore, the angle of the handle 20 affects the load on the user's right hand and right arm.

[0047] From the viewpoint of reducing the load on the user's right hand and right arm, when the straight line passing through the center of gravity P of the knife cutter 1 and the first support portion 50 is defined as the reference line X, it is preferable that the angle θ formed between the reference line X and the axis Y of the handle 20 is 60 degrees or more and 120 degrees or less.

[0048] As described above, the dust generated during the cutting operation is collected in the dust collection case 40. Therefore, when the knife cutter 1 is turned downward after the cutting operation, there is a risk that the dust collected in the dust collection case 40 will leak out from the opening 34 (FIG. 3) of the base 30. Therefore, the knife cutter 1 of the present embodiment has a cover member 80 that forms an accommodation space capable of storing the dust leaking out from the opening 34.

[0049] As shown in FIGS. 8 and 9, the cover member 80 is detachable from the base 30. When the cover member 80 is attached to the base 30, it covers at least a part of the opening 34 (FIG. 3) provided in the base 30.

[0050] As shown in FIGS. 10(a) and 10(b), the cover member 80 includes a bottom portion 81, a side wall portion 82, and a movable piece 83 integrally formed of a resin material, and has a container shape as a whole. As shown in FIG. 11, the cover member 80 attached to the base 30 forms an accommodation space 84 communicating with the dust collection case 40 via the opening 34 on the base 30. This accommodation space 84 is mainly partitioned by the bottom portion 81 and the side wall portion 82 of the cover member 80. The accommodation space 84 formed on the base 30 by the cover member 80 has a volume capable of storing a certain amount of dust leaking from the opening 34. Therefore, even if the dust accumulated in the dust collection case 40 leaks from the opening 34, the dust is accommodated in the accommodation space 84 and does not scatter around.

[0051] The accommodation space 84 is not only a space for accommodating dust, but also a space for accommodating the protruding portion of the cutting blade 18. When the cover member 80 is attached to the base 30, the protruding portion of the cutting blade 18 is accommodated inside the cover member 80. That is, the cover member 80 is also a cap member that covers the protruding portion of the cutting blade 18. By covering the protruding portion of the cutting blade 18 with the cover member 80, breakage of the cutting blade 18 is prevented, and there is no risk of accidentally touching the cutting blade 18 and getting injured.

[0052] As shown in FIGS. 10(a) and 10(b), movable pieces 83 are respectively provided on both sides of the side wall portion 82. That is, the cover member 80 is provided with a pair of movable pieces 83.

[0053] One end of each movable piece 83 is a fixed end connected to the side wall portion 82, and the other end of each movable piece 83 is a free end not connected to the side wall portion 82. Further, a slit 85 is provided between each movable piece 83 and the side wall portion 82. When each movable piece 83 receives an external force, it bends in a direction approaching the side wall portion 82 (bends inward) with the fixed end as a fulcrum. Furthermore, a force (restoring force) that attempts to return the movable piece 83 that has bent inward to its original position (state) is generated. That is, the movable piece 83 pushed in the direction approaching the side wall portion 82 attempts to return to a fixed position (the positions shown in FIGS. 10(a) and 10(b)).

[0054] In addition, the cover member 80 is provided with a slit 85. Therefore, the accommodation space 84 shown in FIG. 11 is not a completely closed space. However, the dust leaking from the opening 34 falls toward the bottom of the cover member 80 due to its own weight. Therefore, there is no dust leaking out of the accommodation space 84 from the slit 85, or the amount is extremely small.

[0055] As shown in FIGS. 10(a) and 10(b), a contact portion 83a parallel or substantially parallel to the bottom portion 81 is provided at the free end of the movable piece 83. The bottom surface of the contact portion 83a and the bottom surface of the side wall portion 82 are substantially at the same height. As shown in FIG. 11, when the cover member 80 is attached to the base 30, the bottom surfaces of the contact portion 83a and the side wall portion 82 contact the contact surface 33 of the base 30. More specifically, the bottom surfaces of the contact portion 83a and the side wall portion 82 contact a predetermined region on the contact surface 33 surrounding the opening 34. In other words, the bottom surfaces of the contact portion 83a and the side wall portion 82 form an attachment surface of the cover member 80 with respect to the base 30. When the cover member 80 is attached to the base 30, the opening 34 of the base 30 is surrounded by the attachment surface of the cover member 80. In addition, four protrusions 87 are provided on the bottom surface of the side wall portion 82. When the cover member 80 is attached to the base 30, these protrusions 87 enter the inside of the opening 34 to prevent the cover member 80 from shifting in the front, rear, left, and right directions.

[0056] As shown in FIGS. 10(a) and 10(b), a claw 86 as an engaging portion is integrally formed at an end of a movable piece 83. The claw 86 projects from the bottom surface of the contact portion 83a in the same direction as the longitudinal direction of the movable piece 83. As shown in FIG. 11, the cover member 80 is fixed to the base 30 when the claw 86 engages with the base 30. On the other hand, when the engagement of the claw 86 with the base 30 is released, the cover member 80 can be removed from the base 30. Hereinafter, the attachment / detachment structure of the cover member 80 to / from the base 30 will be described in more detail.

[0057] As shown in FIG. 12(a), a first opening 34a is provided in the main body portion 31 of the base 30. On the other hand, as shown in FIG. 12(b), a second opening 34b is provided in the cover portion 32. As shown in FIG. 13, when the cover portion 32 is attached to the main body portion 31, the first opening 34a and the second opening 34b communicate with each other to form an opening 34. In other words, the opening 34 of the base 30 is composed of the first opening 34a provided in the main body portion 31 and the second opening 34b provided in the cover portion 32.

[0058] The opening area of the second opening 34b shown in FIG. 12(b) is smaller than the opening area of the first opening 34a shown in FIG. 12(a). Specifically, while the widths of the first opening 34a and the second opening 34b are substantially the same, the total length L2 of the second opening 34b is shorter than the total length L1 of the first opening 34a. For this reason, as shown in FIG. 13, when the first opening 34a and the second opening 34b communicate with each other, the front and rear edges of the second opening 34b are located inside the front and rear edges of the first opening 34a.

[0059] Here, the distance D1 between the pair of claws 86 shown in Fig. 10(a) is wider (longer) than the overall length L2 of the second opening 34b shown in Fig. 12(b). Therefore, when trying to insert the pair of claws 86 inside the opening 34, each claw 86 abuts against the front and rear edges of the second opening 34b. When the cover member 80 is pressed against the base 30 with each claw 86 abutting against the front and rear edges of the second opening 34b, the movable piece 83 bends inward. As a result, the distance D between the pair of claws 86 temporarily narrows, and those claws 86 are pushed inside the second opening 34b. After that, when the pair of claws 86 are pushed inside the second opening 34b (when the pair of claws 86 pass through the front and rear edges of the second opening 34b), the movable piece 83 returns to its fixed position, and the distance D1 between the pair of claws 86 widens. Then, each claw 86 engages with the front and rear edges of the second opening 34b. As a result, as shown in Fig. 11, the cover member 80 is fixed to the base 30.

[0060] In addition, when the movable piece 83 shown in Fig. 11 is bent inward, the distance D1 between the pair of claws 86 temporarily narrows, and the engagement of those claws 86 with the second opening 34b is released. That is, the cover member 80 can be removed from the base 30.

[0061] As shown in Fig. 14, a pair of holding portions 90 for holding the cover member 80 removed from the base 30 are provided on the housing 10. Those holding portions 90 are provided on the side surface of the housing 10. More specifically, the holding portions 90 are provided on the side surface of the base support portion 12.

[0062] As shown in Fig. 15, by fitting the cover member 80 between the pair of opposing holding portions 90, the cover member 80 is held by the holding portions 90. By holding the cover member 80 removed from the base 30 with the holding portions 90, loss of the cover member 80 is prevented.

[0063] The cover member 80 is fitted between the pair of holding parts 90 such that the movable piece 83 is sandwiched between the two holding parts 90 and the contact parts 83a rest on the respective holding parts 90. The holding parts 90 hold the cover member 80 at a position where the cover member 80 does not protrude from the contact surface 33 of the base 30. Specifically, the holding parts 90 are provided at a height such that when the cover member 80 is held as described above, the claws 86 of the cover member 80 are positioned below the contact surface 33.

[0064] As shown in FIG. 10(a), convex parts 83b are provided on the side surfaces of the respective movable pieces 83. As shown in FIG. 16, each convex part 83b is positioned inside the holding claws 90a of the holding part 90 when the cover member 80 is held by the holding part 90. However, the distance D2 between the two convex parts 83b is slightly wider than the distance D3 between the two holding claws 90a. Therefore, when the cover member 80 is fitted between the pair of holding parts 90, the convex parts 83b contact the holding claws 90a and temporarily deflect the holding part 90. That is, the cover member 80 enters between the holding parts 90 while temporarily widening the distance D3 between the pair of holding parts 90. When the convex part 83b passes through the holding claw 90a and enters inside the holding claw 90a, the holding claw 90a returns to its original position and holds the cover member 80.

[0065] As shown in FIG. 17, the knife cutter 1 is provided with a hook 95. The hook 95 is screwed to the side surface of the housing 10 and is hooked on a handrail of an aerial work platform, a pipe for a scaffold, or the like. The hook 95 shown in FIG. 17 is hooked on a pipe 96 for a scaffold. When performing a cutting operation on a scaffold assembled by the pipe 96, the knife cutter 1 can be temporarily placed by hooking the hook 95 on a nearby pipe 96.

[0066] The mounting position, angle, etc. of the hook 95 are set based on the center-of-gravity position of the knife cutter 1 so that when the hook 95 is hooked onto the pipe 96, the cover member 80 attached to the base 30 faces obliquely upward. In other words, the mounting position, angle, etc. of the hook 95 are set based on the center-of-gravity position of the knife cutter 1 so that the inclination angle of the knife cutter 1 when the hook 95 is hooked onto the pipe 96 becomes the inclination angle at which the cover member 80 attached to the base 30 faces obliquely upward. Thereby, when the knife cutter 1 is temporarily placed using the hook 95, the cover member 80 is prevented from falling off, and dust leakage from the opening 34 is suppressed.

[0067] The hook 95 can be used not only during the operation using the knife cutter 1 but also during the storage of the knife cutter 1. Note that although the illustration of the hook 95 is omitted in some drawings, this is for reasons of convenience.

[0068] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist thereof. For example, the position of the first support portion is not limited to being on the motor housing portion, and the position of the second support portion is not limited to being on the base support portion. However, the deformation and distortion of the base affect the cutting accuracy. Therefore, from the viewpoint of preventing the deformation and distortion of the base, it is preferable that no load or stress is applied to the base when the plate-like body is supported by the first support portion and the second support portion. In the above-described embodiment, both the first support portion 50 and the second support portion 60 are provided in the housing 10. Therefore, when the cutting piece C is supported by the first support portion 50 and the second support portion 60, no load or stress is applied to the base 30. At least, the load and stress applied to the base 30 when the cutting piece C is supported by the first support portion 50 and the second support portion 60 are extremely small, and there is no possibility that the base 30 is deformed or distorted.

[0069] The fixing method of the members forming the first support portion and the second support portion is not limited to the above method. However, in the above embodiment, the rubber member 50a and the rubber member 60a are sandwiched and fixed between the first housing member 10R and the second housing member 10L. Therefore, in addition to the fixing member for fixing the first housing member 10R and the second housing member 10L, there is no need to prepare a fixing member for fixing the rubber member 50a and the rubber member 60a.

[0070] The rubber member (anti-slip member) forming the first support portion and the second support portion may be integrated (integrally molded) with the housing. For example, in another embodiment, the first support portion and the second support portion are formed by a part of the elastomer covering the surface of the housing (for example, the surface of the gripping portion of the handle 20). In still another embodiment, an anti-slip member different from the member forming the first support portion and the second support portion is provided on the first support portion and the second support portion. Further, the rubber member forming the first support portion and the second support portion can be replaced with another member having a high coefficient of friction.

Explanation of Reference Numerals

[0071] 1... knife cutter, 10... housing, 10R... first housing member, 10L... second housing member, 11... motor housing portion, 12... base support portion, 12e... rear end, 13... motor, 15a... small-diameter bevel gear, 15b... large-diameter bevel gear, 16... mounting rod, 17... swing shaft, 18... cutting blade, 20... handle, 21... switch, 30... base, 30e... rear end, 31... main body portion, 32... cover portion, 33... contact surface, 34... opening, 34a... first opening, 34b... second opening, 35... connecting portion, 36... marker, 40... dust collection case, 41... button, 50... first support portion, 50a... rubber member, 60... second support portion, 60a... rubber member, 70... insertion space, 80... cover member, 81... bottom portion, 82... side wall portion, 83... movable piece, 83a... contact portion, 83b... convex portion, 84... accommodation space, 85... slit, 86... claw, 87... protrusion, 90... holding portion 90a... holding claw, 95... hook, 96... pipe, A... ceiling panel, B... opening, C... plate-like body (cut piece), D1, D2, D3... intervals, L1, L2... overall lengths, P... center of gravity, X... reference line, Y... axis line, c1... first surface (front surface), c2... second surface (back surface), θ... angle

Claims

1. A housing that houses a motor, A cutting blade driven by the motor, A first support portion provided on the housing, A second support portion provided on the housing and spaced apart from the first support portion, and having, By bringing the first surface of the plate-like body into contact with the first support portion and bringing the second surface of the plate-like body on the side opposite to the first surface into contact with the second support portion, the plate-like body can be supported, A cutting work machine, wherein each of the first support portion and the second support portion includes an anti-slip portion that comes into contact with the plate-like body.

2. A housing that houses a motor, A cutting blade driven by the motor, A first support portion provided on the housing, A second support portion provided on the housing and spaced apart from the first support portion, and having, By bringing the first surface of the plate-like body into contact with the first support portion and bringing the second surface of the plate-like body on the side opposite to the first surface into contact with the second support portion, the plate-like body can be supported, When the first surface of the plate-like body inserted between the first support portion and the second support portion is pressed against the first support portion, the second surface of the plate-like body is pressed against the second support portion by the force that attempts to rotate the plate-like body with the first support portion as a fulcrum, A cutting work machine, wherein the second support portion is provided with an anti-slip portion that comes into contact with the plate-like body.

3. A housing that houses a motor, A cutting blade driven by the motor, A first support portion provided on the housing, A second support portion provided on the housing and spaced apart from the first support portion, and having, By bringing the first surface of the plate-like body into contact with the first support portion and bringing the second surface of the plate-like body on the side opposite to the first surface into contact with the second support portion, the plate-like body can be supported, A cutting work machine, wherein each of the first support portion and the second support portion is made of rubber.

4. In the cutting work machine according to Claim 1, The housing is composed of a first housing member and a second housing member that are abutted against each other, A cutting work machine, wherein at least one of the anti-slip portions provided on each of the first support portion and the second support portion is sandwiched and fixed between the first housing member and the second housing member.

5. In the cutting work machine according to Claim 1, It has a handle provided on the lower side of the housing and a base provided on the upper side of the housing. A cutting work machine in which the first support portion and the second support portion are disposed between the handle and the base in the vertical direction. **Claim 6**: A housing having a motor housing portion for housing a motor, a cutting blade driven by the motor, a first support portion provided on the housing, a second support portion provided on the housing and spaced apart from the first support portion, and a handle provided below the motor housing portion and a base provided above the motor housing portion, the housing is formed by fixing the first housing member and the second housing member to each other in a butted state, the first support portion and the second support portion are disposed between the handle and the base in the vertical direction, the housing has an extending portion extending along the longitudinal direction of the base above the motor housing portion, when the longitudinal direction of the base is defined as the front-rear direction, the first support portion is disposed behind the rear end of the base, the second support portion is provided on the extending portion and is disposed in front of the rear end of the base, A cutting work machine capable of supporting the plate-like body by bringing a first surface of the plate-like body into contact with the first support portion and bringing a second surface of the plate-like body opposite to the first surface into contact with the second support portion. **Claim 7** In the cutting work machine according to claim 6, the housing includes a motor housing portion for housing the motor and a base support portion for supporting the base, the first support portion is provided on the motor housing portion, the second support portion is provided on the base support portion. **Claim 8** In the cutting work machine according to claim 6 or 7, a cutting work machine in which an angle formed by the center of gravity of the cutting work machine, a straight line passing through the first support portion, and the axis of the handle is 60 degrees or more and 120 degrees or less. **Claim 9** In the cutting work machine according to claim 1, a cutting work machine in which the area where the second support portion contacts the plate-like body is larger than the area where the first support portion contacts the plate-like body. **Claim 10** In the cutting work machine according to claim 4, the second support portion has a concavo-convex structure that deforms when the plate-like body is pressed. **Claim 11** In the cutting work machine according to claim 7, The housing is provided with a holding portion capable of holding a cap member that covers a part of the cutting blade protruding upward from the base by being attached to the base. In the housing, a U-shaped portion is formed by the extending portion and the motor housing portion. A insertion space into which the plate-like body can be inserted is formed by the U-shaped portion, and the cap member held by the holding portion is located in front of the insertion space, a cutting working machine.

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