JPH09141602A - Portable cutting tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately ensure the squareness of a saw blade to a base and to efficiently radiate the heats from a gear and a motor via the base. SOLUTION: The portable cutting tool comprises a motor 1, a reduction gear block 2 for decelerating the output of the motor 1, a reduction gear case 7 for containing the block 2, a housing 3 for containing the case 7, an output shaft 4 protruded from the block 2, a saw blade 5 mounted at the shaft 4, and a base 6 brought into contact with the member to be cut at the time of cutting. The rigid base 6 is directly coupled to the case 7 of the block 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable cutting tool.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 6, a speed reduction block 2 in a cutting tool is housed in a speed reducer case 7, and the speed reducer case 7 separated from a main body housing 8 is a main body housing 8. The main body housing 8 is fixed to the base 6 that is applied to the member to be cut at the time of cutting.

[0003]

However, in the conventional example as described above, the reduction gear case 7 having the output shaft 4 is connected to the base 6 via the main body housing 8 of the molded product, and Since the main body housing 8 made of a molded product intervenes in the above, there is a drawback that an error in connecting the speed reducer case 7 to the base 6 is likely to occur and it is difficult to ensure the verticality of the saw blade 5 with respect to the base 6. In a circular saw for operation or the like which requires a right angle accuracy of 5 and the base 6, it is necessary for the user to adjust the angle of the saw blade 5 by providing an angle adjusting mechanism.

Further, since the speed reducer case 7 is connected to the base 6 via the main body housing 8 of the molded product, that is, the main body housing 8 of the molded product is provided between the speed reducer case 7 and the base 6. The deceleration block 3 because it is interposed
There is a problem that the heat generated by the motor 1 cannot be dissipated through the base 6, and the heat is trapped inside the main body housing 8 of the molded product.

An object of the present invention is to solve the above problems. A first object of the present invention is to ensure an accurate squareness between a saw blade and a base, and heat generated from a gear or a motor is transmitted through the base. A second object of the present invention is to provide a portable cutting tool which is capable of efficiently radiating heat.

[0006]

In order to achieve the above object, in the invention of claim 1, a motor 1, a deceleration block 2 for decelerating the output of the motor 1, and a reduction gear case 7 for accommodating the deceleration block 2 are provided. And a housing 3 for accommodating a speed reducer case 7, an output shaft 4 emerging from the speed reduction block 2, a saw blade 5 attached to the output shaft 4, and a base 6 for contacting a member to be cut at the time of cutting. In Tool A,
Rigid base 6 and reducer case 7 of reduction block 2
In order to connect the base 6 and the speed reducer case 7 without interposing a member made of a molded product between the base 6 and the speed reducer case 7, It is possible to minimize the connection error of (1) and to ensure the right angle between the saw blade 5 and the base 6 accurately.

According to a second aspect of the present invention, the base 6 and the speed reducer case 7 in the first aspect are formed of a material having high thermal conductivity, and the heat generated from the gear and the motor 1 is reduced. Heat can be efficiently dissipated through the case 7 and the base 6. In the invention of claim 3, claim 2
In the above, the motor 1 is directly connected to the speed reducer case 7.
The accuracy of the installation position of can be improved.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A portable cutting tool according to the present invention comprises a main body 8 made of a molded product having a thin flat shape as shown in FIG. 1 is provided with a base 6 made of a metal material such as aluminum that is brought into contact with the outer surface of the member to be cut.

A handle portion 9 is integrally provided at the rear portion of the main body 8, and a battery portion 11 to which a battery 10 is detachably attached is provided at the rear portion of the handle portion 9. A motor 1 is installed on one side of the main body 8, and a saw blade 5 is installed on the front part of the main body 8. The saw blade 5 is mounted on the other side of the main body 8 via a speed reduction block 2 on the other side of the motor 1. It is designed to be driven to rotate at.

As shown in FIGS. 4 and 5, the speed reduction block 2 is a speed reducer case 7 made of a metal material such as aluminum.
The motor holding portion 12 for holding the motor 1 is integrally provided at one end of the reduction gear case 7, and the connecting arm 13 pivotally supported by the front end portion of the base 6 is integrally provided at the other end. A gear holding portion 15 is provided in the middle portion, which is formed in the shape of a receiving box and to which the case cover 14 can be attached. The gear holding portion 15 holds the reduction block 2 rotatably. It has become.

As shown in FIGS. 1 and 3, a first gear 16 is arranged at one end of the gear holding portion 15 so that the entire reduction gear case 7 is exposed to the outside. It is meshed with an output gear 17 attached to the output shaft 1a of the motor 1 held by the motor holding portion 12. A second gear 19 is attached to a shaft 18 to which the first gear 16 is fixed, and the second gear 19 is housed in the speed reducer case 7 so as to be located inside the first gear 16. There is.
A third gear 20 is attached to an intermediate portion of the gear holding portion 15, and the second gear 19 is meshed with the third gear 20. A fourth gear 21 is arranged at the other end of the gear holding portion 15 so as to be hidden in the speed reducer case 7, and the third gear 20 is meshed with the fourth gear 21. 22
Is a shaft supporting the third gear 20.

The fourth gear 21 is connected to the output shaft 4. One end of the output shaft 4 is supported in a bearing provided in the case cover 14, and the other end of the output shaft 4 is the outer surface of the reduction gear case 7. It is designed to project further outward. In the portion where the output shaft 4 is arranged, a tubular connecting tube 23 is integrally provided so as to project from the outer surface of the reduction gear case 7 toward the side opposite to the mounting position of the case cover 14, as shown in FIG. The bearing is housed in the connecting cylinder 23, the output shaft 4 is supported by the bearing, and the tip of the output shaft 4 projects outward from the bearing and the connecting cylinder 23.

A connecting hole 24 is provided in the lower portion of the front end of the main body 8 as shown in FIG. 3 (b).
The other end of the reduction gear case 7 and the main body 8 are connected to each other by inserting and arranging the connecting cylinder 23 projecting from the reduction gear case 7 therein. Further, in the speed reducer case 7, the connecting piece 25 protruding from the outer end of the gear holding portion 15 is connected to the main body 8 by a fastener, and the connecting piece 25 protruding from the outer end of the motor holding portion 12 is connected. The main body 8 is connected and fixed to each other by being connected to the main body 8 by a fixing tool.

The connecting cylinder 23 of the speed reducer case 7 is inserted through the connecting hole 24 of the main body 8 so as to project inside the main body 8.
A disk-shaped saw blade support plate is attached to the more protruding output shaft 4, and a support projection of the saw blade support plate is inserted into a connecting hole at the center of the saw blade 5 so that the output shaft 4 has a front end portion. The pressing plate is inserted into the shaft, the fixing nut screwed to the tip of the output shaft 4 is tightened, the pressing plate is pressed by the fixing nut, and the saw blade 5 is sandwiched between the pressing plate and the saw blade support plate. The saw blade 5 is attached to the output shaft 4.

A reducer block cover 3a as a housing 3 is attached to the other side of the main body 8 so as to cover the reducer case 7 in an attached state on the outer surface side of the reducer case 7 arranged on the other side of the main body 8. It is like this. The speed reducer block cover 3a as the housing 3 is provided with a lock button 26 for locking the speed reduction block 2. By pushing this lock button 26 inward, the speed reduction block 2 is locked and the output shaft 4 is locked. It can be prevented from rotating, and when the saw blade 5 is replaced, the lock button 26 is pushed inward to reduce the speed of the speed reduction block 2.
By making the lock state, the fixing bolts screwed to the output shaft 4 can be loosened and the saw blade 5 can be removed.

The connecting arm 13 is projected from the speed reducer block cover 3a mounted so as to cover the speed reducer case 7, and the front end of the connecting arm 13 has no rattling at the front end of the base 6. Is supported by the main body 8 while holding the motor 1 and the deceleration block 2.
The speed reducer case 7 attached to the other side is directly coupled to the base 6. That is, a pair of connecting support pieces 40 having connecting holes 40a are provided so as to project upward from the upper surface of the front end portion of the base 6, and a connecting hole is provided at the tip of the connecting arm 13 in the width direction. The tip of the connecting arm 13 is disposed between the pair of connecting support pieces 40, and the connecting hole of the connecting support piece 40 and the connecting hole of the connecting arm 13 are aligned with each other to press the connection pin 41 into each connecting hole. As a result, the tip of the connecting arm 13 is pivotally supported so that the front end of the base 6 does not rattle. Here, the connection between the connection arm 13 and the connection support piece 40 is performed by the connection pin 4
Fixing devices such as bolts and nuts other than 1 may be used, and the point is that the connecting arm 13 can be rotatably supported on the connecting support piece 41 without rattling. . The reducer case 7 and the base 6, both of which are made of a rigid material such as a metal material such as aluminum, are directly coupled to each other, and the reduction block 2 and the motor 1 are connected to each other.
It is connected to the base 6 via. Here, the speed reducer case 7 and the base 6 are directly coupled to each other, and the speed reducer case 7 and the base 6 are formed of a metal material such as aluminum as a material having high thermal conductivity. Generates heat from the reducer case 7 and base 6
Through this, heat can be efficiently dissipated, and the heat resistance and reliability of the mechanical section can be improved.

Further, here, the connecting arm 13 is connected to the base 6
Is pivotally supported on the front end of the base 6 so that the base 6 can be rotationally moved about the pivotal support, and the rear end of the base 6 is rotationally moved in a direction away from the main body 8. As a result, the protruding amount of the saw blade 5 protruding downward from the long groove 27 of the base 6 can be reduced, and by rotating the rear end of the base 6 toward the main body 8, the long groove 27 of the base 6 can be moved. This is because it is possible to increase the amount of protrusion of the saw blade 5 that protrudes downwardly from, and to arbitrarily adjust the cutting depth of the member to be cut by the saw blade 5. When the base 6 is rotationally moved, the base 6 is rotationally moved and then fixed at a predetermined position by a support member 28 provided at the rear end of the base 6. The support member 28 is provided with a support bar 30 having a long hole 29 projecting upward from the rear end of the base 6.
0 is slidably inserted into the lower portion of the main body 8, and the support bar 30 is fixed at a predetermined position by tightening a screw tool 31 attached to the main body 8 so as to pass through the elongated hole 29. It is possible to fix the base 6 at an arbitrary position after rotating the base 6 by a predetermined angle.

From the front end of the handle portion 9 provided on the main body 8, projections 32 are integrally projected toward both sides orthogonal to the main body 8, and the auxiliary grip 33 is formed by the projections 32. There is. A fixed cover 34 is provided at the front of the main body 8, and the fixed cover 34 covers substantially the upper half of the saw blade 5, and the lower half of the saw blade 5 is the base as described above. 6 protrudes downward from the long groove 27 provided in 6. A movable cover 35 is provided at the bottom of the main body 8, and the movable cover 35 is used to form the long groove 2.
The lower half of the saw blade 5 projecting downward from 7 is covered. This movable cover 35 has a connecting ring,
When connecting the connecting cylinder 23 of the speed reducer case 7 to the connecting hole 24 of the main body 8, the connecting ring is rotatably engaged with the connecting cylinder 23 of the speed reducer case 7 protruding from the connecting hole 24 to connect. By engaging a retaining ring with the tip of the cylinder 23, it is coupled to the connecting cylinder 23 of the speed reducer case 7 so as to be rotatable together with the main body 8 while retaining the retaining ring. When the saw blade 5 is not rotated, it covers substantially the lower half of the saw blade 5 protruding below the base 6, and when the saw blade 5 is rotated, the saw blade 5 is rotationally moved and stored inside the fixed cover 34. The lower half of the blade 5 is exposed. Here, the movable cover 35 is spring-biased by a spring material so that the movable cover 35 is always arranged at a position that covers approximately the lower half of the saw blade 5, and the member to be cut is moved by the movable cover 35 when the member to be cut is cut.
When the saw blade 5 cuts the member to be cut, the movable cover 35 rotates and moves against the spring force of the spring material and enters the fixed cover 34.

The fixed cover 34 is formed of a transparent resin plate or the like so that it is easy to confirm the cutting start position of the member to be cut from above the main body 8 through the fixed cover 34. The base 6 having a quadrangular shape in plan view is configured by projecting a reinforcing piece 38 upward from an appropriate position on the upper surface of a flat plate member 37 having a long groove 27 in the central portion.
A flange piece 39 is provided on the peripheral edge so as to project upward, and a cutting guide ruler for guiding the cutting direction when cutting the member to be cut can be detachably attached to the base 6. It is like this.

Therefore, the reduction block 2, the motor 1 and the main body 8 are connected and fixed to the reduction gear case 7, and the connection arm 13 protruding from the reduction gear case 7 is directly pivotally supported on the base 6. The rotating saw blade 5 is connected to the output shaft 4 projecting from the speed reducer case 7 to form the portable cutting tool A, that is, the speed reducer case 7 is used as a base for the base 6 of the speed reducer case 7. And the main body 8 and the saw blade 5 are attached to the speed reducer case 7 to form the portable cutting tool A, which is formed between the base 6 and the speed reducer case 7. Since a member made of a product is not interposed, a connection error in connecting the base 6 and the reducer case 7 can be minimized, and the squareness between the saw blade 5 and the base 6 can be accurately ensured. What you can do A.

[0021]

According to the invention of claim 1, a motor, a deceleration block for decelerating the output of the motor, a housing for accommodating the deceleration block, an output shaft extending from the deceleration block, and a saw blade attached to the output shaft. In a portable cutting tool consisting of a base that is applied to the member to be cut when cutting, both the rigid base and the speed reducer case of the speed reduction block are directly connected, so that between the base and the speed reducer case. Without interposing a member made of a molded product, it is possible to minimize the connection error when connecting the base and the reduction gear case, and to ensure the right angle between the saw blade and the base. Therefore, it is possible to provide a lightweight, inexpensive, portable cutting tool that does not require an angle adjusting mechanism or the like and has high reliability.

According to the second aspect of the present invention, in the first aspect, the base and the reducer case are made of a material having high thermal conductivity. Therefore, in addition to the effect of the first aspect, heat generated from the gear and the motor is generated. It can efficiently dissipate heat through the reducer case and the base, and the heat resistance of the mechanical part,
The reliability can be improved. Claim 3
According to the invention of claim 2, since the motor is directly connected to the speed reducer case in claim 2, in addition to the effect of claim 2, the accuracy of the installation position of the motor with respect to the speed reduction block can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of the present invention with a housing removed.

FIG. 2 is an external perspective view of the same.

FIG. 3A is a partially omitted side sectional view showing an arrangement state of a reduction gear block and a reduction gear case, and FIG. 3B is a partial side view of a main body showing a connection hole.

FIG. 4 is an explanatory diagram illustrating a coupled state of the reduction gear case and the base.

FIG. 5 is an explanatory diagram illustrating a coupled state of the reduction gear case and the base.

FIG. 6 is a side sectional view showing a conventional example.

[Explanation of symbols]

 A Portable cutting tool 1 Motor 2 Reduction gear block 3 Housing 4 Output shaft 5 Saw blade 6 Base 7 Reduction gear case

Claims (3)

[Claims] 1. A motor, a deceleration block for decelerating the output of the motor, and a reduction gear case housing the deceleration block,
In a portable cutting tool consisting of a housing that houses the reducer case, an output shaft from the speed reduction block, a saw blade attached to the output shaft, and a base that is applied to the member to be cut during cutting, both the rigid base and the speed reducer A portable cutting tool characterized by being directly coupled to a block reducer case. 2. The portable cutting tool according to claim 1, wherein the base and the reducer case are made of a material having high thermal conductivity. 3. The portable cutting tool according to claim 1, wherein the motor is directly connected to the speed reducer case.