JP5381174B2 - Portable cutting machine - Google Patents

Description

  The present invention relates to a portable cutting machine.

  Generally, in a portable cutting machine equipped with a battery, when a battery is attached, whenever a trigger provided on the handle is pulled, power is supplied and the saw blade rotates. Therefore, even if the operator touches the trigger unintentionally or when force is applied to the trigger due to an external factor, the saw blade rotates, so the portable cutting machine has a trigger lock mechanism. And consideration is given to safety.

  In the trigger lock mechanism, a rocking link that is physically inserted between the trigger switch and the switch box and interferes with the operation of the trigger is arranged, and the rocking link is rocked to release the locked state. By pressing a lock release switch (see Patent Documents 1 and 2), a system that ensures a sufficient free running distance (play) on the switch lever to prevent malfunctions, etc. (see Patent Document 3) A method of electrically releasing the lock state is known.

Japanese Patent Publication No. 8-32396 Japanese Examined Patent Publication No. 7-90521 JP 2008-173732 A

  However, the system using the swing link is configured such that the middle part of the swing link is pivotally attached to the handle, the swing link is swung, and the tip of the swing link is directly locked to the end of the trigger switch. Therefore, if the length from the fulcrum to the tip of the swing link is long, the motion of the tip of the swing link is close to a straight line. For this reason, the operation trajectory drawn by the tip of the swing link in the gap between the trigger switch and the switch box becomes linear, and therefore the interval between the trigger switch and the switch box may be small. On the other hand, the arrangement space of the swing link must be increased.

  On the other hand, if the length from the fulcrum to the tip of the swing link is short, the space for the swing link may be small, but the tip moves between the trigger switch and the switch box while moving in an arc shape. It will be inserted and pulled out. Thus, since the operation locus drawn in the gap between the trigger switch and the switch box by the tip of the swing link is an arc, the interval between the trigger switch and the switch box must be increased. If the interval is increased, the stroke of the trigger switch is increased, and there is a problem that the operability is not good because it takes time until the switch is turned on after the operation. The same applies to the switch mechanism of Patent Document 3.

  As described above, if the operability of the trigger is regarded as important, there is a problem that the arrangement space of the swing link has to be increased, and if the arrangement space is reduced, the operability is impaired.

  Further, in the method of electrically controlling the on / off of the trigger switch, there is a problem that the lock release switch and the trigger switch must have a special switch configuration, resulting in high cost.

  The present invention solves the above-mentioned problems, and provides a portable cutting machine having a trigger lock mechanism that can stably perform locking and unlocking operations without requiring a special switch and without a large space. The issue is to provide.

In order to solve the above-mentioned problem, the invention according to claim 1 is provided with a surface plate placed on a material to be cut at a lower portion of a cutting machine body that rotatably supports an electric motor and a saw blade , An operation handle is arranged on the upper part, the lower part of the saw blade is protruded downward from an opening formed in the surface plate, and the rotation shaft of the saw blade is rotated via a speed reduction mechanism by rotating the output shaft of the electric motor. In the portable cutting machine to be transmitted to the first, the first is disposed between the switch box provided with the switch of the operation circuit of the electric motor and the trigger switch provided so as to be able to push and release the switch by reciprocating motion. And an off-lock lever having one end engaged with the first off-lock lever, and a second off-lock lever swingably provided on the cutting machine body, and the second off-lock lever is swung. First by The off-lock lever to pull actuated from between the switch box and the trigger switch, the the first off-lock lever, trigger the opening frame section at the top of the removably locking portion into the gap between the switch box The second off-lock lever has one end engaged with the opening frame portion, the other end having an operation portion, and an intermediate portion rotatably supported on the cutting machine body side. Both ends protrude from the operation window opened in the operation handle to both sides .

  According to the first aspect of the present invention, since the first off-lock lever is disposed between the switch box and the trigger switch so as to be detachable by the straight movement, the first switch is not provided between the switch box and the trigger switch. It is sufficient if there is a gap that is approximately the same as the thickness of the 1 off-lock lever. Therefore, since the distance between the trigger switch and the switch box can be shortened, there is almost no time lag between the operation of the trigger switch and the switch-on operation, so that the operability is good.

  Further, the operation locus of the second off-lock lever has nothing to do with the gap between the switch box and the trigger switch. That is, the operating portion of the second off-lock lever only needs to operate the first off-lock lever, and may be sufficiently short. Therefore, the space for housing the second off-lock lever can be small, and the whole can be made more compact.

  Therefore, a special switch is not required, and the lock operation and the unlock operation can be stably performed even without a large space.

In addition , the first off-lock lever is formed with an opening frame portion on the upper portion of the lock portion that can be inserted and removed in the gap between the trigger switch and the switch box, and one end of the second off-lock lever has the above-described opening. Engaging with the frame part and having an operation part at the other end, and the intermediate part is rotatably supported on the cutting machine main body side, the swinging of the second off-lock lever is effectively prevented from the first part. The effect according to claim 1 can be realized by converting into a straight movement of the off-lock lever.

Side view of portable cutting machine according to the present invention Sectional view on the XX line of FIG. Enlarged perspective view of the trigger lock mechanism of the portable cutting machine Side view showing part of FIG. 3 in cross section Perspective view of main part of trigger lock mechanism Enlarged perspective view when the trigger lock mechanism is unlocked Side view showing part of FIG. 6 in cross section

  1 and 2, the symbol A indicates a portable cutting machine. In this cutting machine, a cutting machine body 3 in which a saw blade 1 and an electric motor 2 for driving the saw blade 1 are juxtaposed is supported on the upper part of the surface plate 6, and an operation handle is placed on the upper part of the cutting machine body 3. 4 is arranged in the front-rear direction, and a battery pack 5 for driving the electric motor is detachably provided at the lower rear end of the handle 4.

  A first reduction gear 10 fixed to one end of the intermediate shaft 8 meshes with the output shaft 7 of the electric motor 2, and a second reduction gear 11 fixed to the other end of the intermediate shaft 8 is fixed to the final shaft 9. 3 is engaged with the reduction gear 12 and the saw blade 1 is fixed to the final shaft 9. Thereby, when the electric motor 2 rotates, the rotational force is transmitted to the final shaft 9 via the first, second, and third reduction gears 10, 11, and 12, and the saw blade 1 rotates.

  The surface plate 6 is a metal plate-like member provided at the lower part of the cutting machine main body 3, and an opening 6 a is formed through a part of the plate 6, and one of the saw blades 1 is formed below the opening 6 a. The part is exposed and covered with an arc-shaped lower guard 14. The lower guard 14 is mounted so as to be rotatable upward from the rear about the rotation axis of the saw blade 1.

  Further, the operation handle 4 is disposed at the upper part of the cutting machine body 3, the front part thereof is integrally provided on the motor housing 13 side of the front part of the cutting machine body 3, the rear part is bent, and the bent end is bent. The portion is integrally provided on the rear surface of the cutting machine body 3. A mounting portion for the battery pack 5 having a known attachment / detachment mechanism is formed between the lower portion of the bent portion 4a and the surface plate 6, and the battery pack 5 is inserted and mounted from the rear of the mounting portion to release the lock. It can be pulled out and removed later.

  A switch mechanism for controlling on / off of the electric motor 2 and a trigger lock mechanism for locking the trigger so as not to be inadvertently provided are provided at the front portion of the operation handle 4.

  As shown in FIGS. 3 and 4, the switch mechanism includes a trigger 15 and a switch box 16 provided inside the operation handle 4 and arranged to face the trigger 15. The projecting shaft 17 provided at the base of the trigger 15 is provided so as to be able to press the switch 19 of the operation circuit of the electric motor 2 provided in the switch box 16. The trigger 15 is constantly urged by a spring (not shown) so that the projecting shaft 17 is separated from the switch 19, and when the trigger 15 is pushed and released, the projecting shaft 17 contacts and separates from the switch 19 and the switch of the electric motor 2 is turned on / off. It is configured as follows. The switch mechanism is not special and is a general-purpose switch mechanism.

  Next, as shown in detail in FIG. 5, the trigger lock mechanism includes a first off-lock lever 20 and a second off-lock lever 21 that operates the first off-lock lever 20. .

  The first off-lock lever 20 is formed by forming an opening frame portion 18 on the upper portion of the lock portion 22, and the lock portion 22 can be inserted into and removed from the gap between the trigger 15 and the switch box 16 by a straight movement. Is provided. The upper bottom surface 18a of the opening frame 18 is inclined downward to make the opening 33 smaller. A spring receiver 23 is formed on the upper portion of the opening frame 18, and a compression spring 24 (see FIGS. 3 and 4) is disposed between the spring receiver 23 and the upper surface of the inner wall of the operation handle. By this compression spring 24, the lock portion 22 is constantly urged to enter the gap between the trigger 15 and the switch box 16 as shown in FIG.

  Note that guide pieces 25 are formed on both sides of the lock portion 22 at right angles to the lock portion 22. The guide piece 25 is engaged with a guide groove (not shown) formed on the operation handle 4 side. Thereby, the first off-lock lever 20 is guided so as to be able to move straight.

  The second off-lock lever 21 is swingably provided inside the operation handle 4, and the opening member 18 of the first off-lock lever 20 is provided on one side of a central member 26 a having a rotation shaft 26 on both sides. An operating piece 28 entering inward is formed by projecting a substantially T-shaped operating portion 27 on the other side, and both ends of the rotating shaft 26 are bearing portions (both bearing portions formed on opposite side walls of the operating handle 4). (Not shown) is rotatably fitted. Both ends 30a of the operation unit 30 are exposed to the outside of the operation handle 4 so that they can be operated from the outside. Note that an arcuate guide piece 26 b is formed on the outer side of the rotation shaft 26 in the operation portion 27.

  The trigger lock mechanism is accommodated in the internal space S of the front corner portion of the operation handle 4. An operation window is opened in this space, and both ends 30a of the operation unit 30 protrude outward from the space. An arcuate guide wall 32 is formed inside the window portion 31 on both sides of the through-hole for allowing the second off-lock lever 21 to pass therethrough, and the guide piece 26 b of the second off-lock lever 21 and the operation portion 30. The bulging part including the both ends 30a of the guide wall 32 is disposed.

  According to the above configuration, as shown in FIGS. 3 and 4, the trigger 15 is normally separated from the switch box 16 by a spring bias, that is, at a position far from the switch contact. Further, since the lock portion 22 of the first off-lock lever 20 is urged by the compression spring 24 so as to enter the gap between the trigger 15 and the switch box 16, it is inserted into the gap. As a result, even if the trigger 15 receives an external force that moves to the switch box 16 side for some reason, it does not operate because it is locked by the first off-lock lever 20.

  On the other hand, when the operating portion 30 of the second off-lock lever 21 is first operated to swing, the operating piece 28 swings about the rotation shaft 26 as shown in FIGS. As a result, the opening frame 18 of the first off-lock lever 20 is lifted, so that the first off-lock lever 20 moves straight upward, and the lock 22 is pulled out from the gap between the trigger 15 and the switch box 16. . As a result, since there is no interference with the trigger 15, the protruding shaft 17 of the trigger 15 is pushed in this state, the switch 19 of the switch box 16 is pressed to operate the electric motor 2, and the saw blade can be rotated. .

  As described above, since the first off-lock lever 20 is disposed between the switch box 16 and the trigger 15 so as to be insertable / removable by the straight movement, the first off-lock lever 20 is disposed between the switch box 16 and the trigger 15. It is sufficient if there is a gap that is approximately the same as the thickness of the off-lock lever 20. Therefore, since the distance between the trigger 15 and the switch box 16 can be shortened, there is almost no time lag between the operation of the trigger 15 and the switch-on operation, so that the operability is good.

  Further, the operation locus of the second off-lock lever 21 has nothing to do with the gap between the switch box 16 and the trigger 15. That is, the operating portion of the second off-lock lever 21 only operates the first off-lock lever 20, and may be sufficiently short. Therefore, the space for storing the second off-lock lever 21 can be small, and the whole can be made more compact.

DESCRIPTION OF SYMBOLS 1 Saw blade 2 Electric motor 15 Trigger 16 Switch box 20 1st off-lock lever 21 2nd off-lock lever 25 Guide piece

Claims (1)

A surface plate placed on the material to be cut is provided at the lower part of the cutting machine main body that rotatably supports the electric motor and the saw blade , and an operation handle is arranged at the upper part of the cutting machine main body. In a portable cutting machine that protrudes downward from the opening formed in the surface plate and transmits the rotation of the output shaft of the electric motor to the rotation shaft of the saw blade via the speed reduction mechanism.
A first off-lock lever disposed so as to be detachable by linear movement between a switch box provided with a switch of the operating circuit of the electric motor and a trigger provided so that the switch can be pushed and released, and one end of the first off-lock lever And a second off-lock lever that is swingably provided on the cutting machine body, and the first off-lock lever is moved by swinging the second off-lock lever. Pull out from between the switch box and the trigger ,
The first off-lock lever is formed with an opening frame on the upper portion of the lock portion that can be inserted and removed in the gap between the trigger and the switch box, and one end of the second off-lock lever is formed on the opening frame. Engaging and having an operation part at the other end, the intermediate part is rotatably supported on the cutting machine body side,
A portable cutting machine characterized in that both ends of the operation part protrude on both sides from an operation window opened in the operation handle .

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