JP2010082713A - Saber saw - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a saber saw capable of setting an optimum mounting angle of a blade according to a kind of the attached blade and a material to be cut. <P>SOLUTION: The saber saw includes: a motor; a motion conversion means for converting rotation motion of the motor to reciprocation motion of a plunger; and a blade holder 23 mounted to a distal end of the plunger 20 in a cantilever manner and retaining the blade 35. The saber saw further includes a mounting angle variable mechanism for changing the mounting angle of the blade 35 relative to the plunger 20. The mounting angle variable mechanism can be constituted integrally with the blade holder 23 and is made turnable making a round hole formed on the blade 35 as a center. On upper and lower part of the blade holder 35, a pair of screws 28a, 28b are provided, and a turning angle of the blade can be changed by these screws. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a saver saw, and more particularly to a saver saw having a mechanism for changing a mounting angle of a blade.

  There is a saver saw as a reciprocating type cutting tool driven by an electric motor. As is well known, a saver saw is used to cut a material to be cut such as wood, steel, and pipe, and a reciprocating shaft (hereinafter referred to as “plunger”) having a straight saw blade (hereinafter referred to as “blade”) attached to the tip. ”) Is reciprocated, and the material to be cut is cut by a blade attached thereto. FIG. 7 is a side view showing a blade attached to a saver saw. The blade 35 has a holding portion 35a and a cutting tooth portion 35b that are held by a blade holding means on the plunger side, and the upper and lower reference surfaces are formed in parallel in the holding portion 35a, and a round hole 35c is interposed therebetween. Is formed. The lower reference surface and the tooth surface of the cutting tooth portion 35b (dotted line in the figure) are provided with an angle of, for example, about 3 ° in order to improve cutting efficiency. A round hole 35c is formed in the holding portion 35d, and this round hole 35 is used when the blade 35 is attached to the blade guide as necessary. By providing an angle to the tooth surface of the blade 35, when the blade 35 slides in the reciprocating motion direction by the plunger, the tooth surface can be bitten into the material to be cut, and workability is improved.

  The holding portion 35a of the blade 35 is held by blade holding means provided at the plunger tip of the saver saw. As the blade holding means, as described in Patent Document 1, a so-called toolless structure that allows the blade to be attached and detached by pushing down the knob cover has become mainstream.

  On the other hand, as another type of saver saw, as described in Patent Document 2, the blade tip is tilted toward the workpiece during the backward stroke of the blade toward the housing, and the blade of the blade is bitten by the workpiece. Saver saws have been proposed that improve cutting efficiency.

JP 2003-205423 A JP 2005-28494 A

  In the technique of Patent Document 1, the blade holding means is attached to the tip of the plunger and cannot move with respect to the plunger. The angle of about 3 ° provided on the blade is set to be optimal for as many materials as possible, but depending on the material to be cut, the angle is not optimal and the setting is not utilized. In some cases, the speed was reduced. Further, in the technique of Patent Document 2, the track portion provided in the longitudinal direction on the upper side of the blade of the blade holder is supported by a roller that is in rotational contact, and when the blade is retracted, by the inclined surface of the track portion and the roller, The blade holding part and the blade rotate in the vertical direction. That is, in the technique of Patent Document 2, the blade swings because the plunger itself that fixes the blade swings, and the mounting angle of the blade cannot be made variable by this swinging mechanism.

  An object of the present invention is to provide a saver saw that eliminates the above-described drawbacks of the prior art and can set an optimum blade mounting angle in accordance with the blade to be mounted and the material to be cut.

  Another object of the present invention is to provide a saver saw that can improve cutting efficiency and reduce worker fatigue.

  Of the inventions disclosed in the present application, typical features will be described as follows.

  According to one aspect of the present invention, a motor, a motion converting means for converting the rotational motion of the motor into a reciprocating motion of the plunger, a housing for accommodating the motor and the motion converting means, and a cantilever attached to the tip of the plunger. In the saver saw having the blade holding means for holding the blade, the mounting angle changing means for changing the mounting angle of the blade with respect to the plunger is provided. The attachment angle varying means can be formed integrally with the blade holding means, and it is particularly preferable that the blade is rotated with respect to the plunger around a round hole formed in the blade. The attachment angle varying means includes a pair of screws provided in the vertical direction of the blade holding means, and the rotation angle can be changed by these screws.

  According to another feature of the present invention, a small-diameter mounting portion that is inserted into the blade holding means is formed at the tip of the plunger, and the blade is formed above and below the mounting portion around a round hole formed in the blade. An inclined surface is formed so that the holding means can be rotated about several degrees. And it was comprised so that the space | interval of the inner wall of a braid | blade holding means and an inclined surface could be adjusted, when the front-end | tip of two screws contact | abuts an inclined surface.

  According to another feature of the present invention, the attachment angle varying means is a second plunger provided between the blade holding means and the plunger, and the second plunger is a rotation axis perpendicular to the reciprocating direction of the plunger. It is configured to be rotatable by a minute angle around the center. The second plunger has an inner housing portion for inserting a small-diameter attachment portion formed at the distal end of the plunger, and an attachment portion that protrudes toward the distal end side to hold the blade holding means. It has two screws from the vertical direction perpendicular to the shaft. By adjusting these two screws, the second plunger can be rotated by a small angle, for example, ± 6 degrees, so that the blade mounting angle is changed.

  According to the first aspect of the present invention, since the mounting angle variable means for changing the mounting angle of the blade with respect to the plunger is provided, the mounting angle of the blade can be adjusted according to the material to be cut. The bite cutting efficiency can be improved, and the cutting operation can be performed efficiently. Further, even when a conventional blade without an angle is attached, the blade angle can be adjusted to an optimum value for the material to be cut.

  According to the second aspect of the present invention, the mounting angle varying means is formed integrally with the blade holding means, and rotates the blade with respect to the plunger around a round hole formed in the blade. Is not moved up and down by the reciprocating motion of the plunger, and a stable cutting operation with less vibration is possible. Further, since the blade holding means and the mounting angle variable means are integrally formed, the number of parts can be reduced, and an increase in manufacturing cost can be prevented.

  According to the invention of claim 3, the mounting angle varying means includes a pair of screws provided in the vertical direction of the blade holding means, and the rotation angle of the blade is changed by these screws. The attachment angle of the blade can be adjusted. In addition, since it is held by the screw in the vertical direction, which is the direction to receive the reaction force from the blade, it is possible to greatly reduce that the adjusted angle is distorted as the work progresses, and to perform stable cutting work. .

  According to the fourth aspect of the present invention, the small-diameter mounting portion inserted into the blade holding means is formed at the tip of the plunger, and the blade is held above and below the mounting portion around the round hole formed in the blade. Since the inclined surface recessed inside is formed so that the means can be rotated, the change in the configuration on the plunger side is slight, and the manufacturing cost can be reduced.

  According to the fifth aspect of the present invention, since the distance between the inner wall of the blade holding means and the inclined surface is adjusted by the tip of the screw coming into contact with the inclined surface, the mounting angle varying means can be realized with a simple configuration.

  According to the invention of claim 6, since the second plunger configured separately from the blade holding means is used as the attachment angle varying means, the attachment angle varying function can be realized without any changes on the blade holding means side. . Further, since the second plunger can be rotated by a minute angle around the rotation axis, the degree of freedom in manufacturing is high.

  According to the invention of claim 7, the second plunger holds the inner holding portion for inserting the small-diameter mounting portion formed at the tip of the (first) plunger and the blade holding means. Since the mounting portion protrudes toward the distal end side, the mounting angle varying means can be realized with a simple configuration.

  According to the invention of claim 8, the second plunger has two screws from the vertical direction perpendicular to the rotation axis, and the relative rotation angle between the two plungers by adjusting these screws. Therefore, it is possible to reduce the deviation of the adjusted angle and perform a stable cutting operation.

  The above and other objects and novel features of the present invention will become apparent from the following description and drawings.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, parts having the same function are denoted by the same reference numerals, and repeated description is omitted. Further, in this specification, description will be made assuming that the front-rear and up-down directions are the directions shown in FIG.

  FIG. 1 is a cross-sectional view showing an entire saver saw according to an embodiment of the present invention. The electric motor 1 is built in a resin motor housing 2, and a handle 3 is connected to the rear of the motor housing 2. The handle 3 has a built-in switch 4 for controlling power supply to the electric motor 1. An aluminum inner cover 5 and a gear cover 6 are provided in front of the motor housing 2 to accommodate the power transmission means. A driving gear 8 is formed at the tip of the motor shaft 7. The rotational motion of the motor shaft 7 is converted into the reciprocating motion of the plunger 20 by the motion converting means. The motion conversion means includes a second shaft 9 provided in parallel with the motor shaft 7, a driven gear 10 attached to the second shaft 9, and an angle of about 14 ° with respect to the axis of the driven gear 10 provided in front of the second shaft 9. An inclined shaft portion 9 a having an angle, a sub shaft 11 concentric with the axis of the driven gear 10, and a reciprocating plate 18 attached to the inclined shaft portion 9 b of the second shaft 9 via two bearings 17. Is done.

  The electric motor 1 rotates the second shaft 9 via the reduction gears (8, 10). The rotational movement of the second shaft 9 is transmitted as the rotational movement of the inclined shaft portion 9a, and rotates the reciprocating plate 18 held by the inclined shaft portion and the sub shaft 11 provided concentrically with the axis of the driven gear 10. A spherical portion 18b is formed at the tip of the rocking shaft portion 18a of the reciprocating plate 18 and penetrates the hole portion 20e of the plunger 20, and the spherical portion 18b is engaged with the inside of the hole portion 20e so that it can roll with a slight gap. To do. A roller shaft 21 passes through the plunger 20, and a swing roller A22 and a swing roller B (not shown) are rotatably attached to both ends of the roller shaft 21, and the swing roller includes a raceway surface A34 and a raceway surface. B (not shown) is provided so as to reciprocate integrally with the plunger 20. With the above configuration, the reciprocating plate 18 moves in the front-rear direction, and as a result, the rotational motion of the second shaft 9 is converted into the reciprocating motion of the plunger 20.

  The blade holder 23 in front of the plunger 20 is configured such that the blade 35 can be attached and detached with one touch by operating a swingable knob cover 26. This configuration will be described later. The blade 35 may be fixed to the blade holder 23 with a blade fixing bolt (not shown) instead of being attached and detached by one operation by operating the knob cover 26.

  The inner cover 5, the gear cover 6, and the motor housing 2 constitute a housing part that constitutes a saver saw. In this embodiment, the housing part is divided into three components (5, 6, 7). These may be a single structure, or may be composed of two or more components. A front cover 33 made of an insulating heat insulating elastic member having a large friction coefficient is provided on a part of the outside of the housing portion. A base 16 is provided at the tip of the gear cover 6, and the saver saw body can be stabilized by pressing the base 16 against the material to be cut during the cutting operation.

  FIG. 2 is a partial side view showing the plunger 20 and blade holding means of FIG. The plunger 20 is held by the housing portion (gear cover 6) by the bearing metal 19 so as to be slidable in the front-rear direction. In this embodiment, the blade 35 is attached to the tip of the plunger 20 that slides in the front-rear direction. The blade holder 23 to which the blade 35 is attached is provided with an attachment angle variable means for changing the angle between the blade 35 and the plunger 20. It was. In order to change the mounting angle, two bolts 28 a and 28 b are provided from the vertical direction of the blade holder 23. A method of adjusting the mounting angle of the blade 35 using the bolts 28a and 28b will be described with reference to FIG.

  FIG. 3 is a side view of the blade holder 23 employing the blade attachment angle changing means according to the present embodiment, where (1) is a side view and (2) is a cross-sectional view taken along line AA of (1). is there. A blade holder 23 is provided in front of the plunger 20. The blade holder 23 is provided with a rotation fixing bolt 28a on the upper side and a rotation fixing bolt 28b on the lower side, and the mounting angle of the blade 35 can be adjusted by tightening or loosening these bolts. It becomes possible, and it functions as a mounting angle variable means. By adjusting the tightening state of the upper and lower bolts 28a, 28b, the angles of the tooth surfaces of the plunger 20 and the blade holder 23 are adjusted. The state of FIG. 3 (1) shows a state in which the adjustment angle of the attachment angle of the blade 35 is 0 °, and the blade 35 is not inclined upward or downward.

  In FIG. 3 (2), the blade holder 23 is connected to the tip of the plunger 20 via a mounting bolt 29 so as to be rotatable by a minute angle. The blade holder 23 is attached so as to cover the thin attachment portion 20a of the plunger 20. A slit 20b that accommodates the blade 35 is formed in the mounting portion 20a of the plunger 20, and the locking pin 31 engages with a round hole 35c of the accommodated blade 35. The locking pin 31 is held by a knob 24 that presses the head of the locking pin 31 to engage the locking pin 31 with the round hole 35c. The knob 24 is mounted on the plunger mounting portion 20a by a fastening bolt 27 via a torsion coil spring 30 to urge the locking pin 31 in a direction in which the locking pin 31 is locked in the mounting hole. In the present embodiment, the fastening bolt 27 is for allowing the knob 24 to rotate by a small angle around the fastening bolt 27 and does not have a function of fixing the blade holder 23 to the plunger 20.

  The knob cover 26 is an operation unit for rotating the knob 24 by a minute angle, and is attached to the knob cover 24 through a cutout hole formed in the blade holder 23. By moving the knob cover 24 downward (in the direction of the arrow of the knob cover 26 in FIG. 2), the pressing of the head of the locking pin 31 is released, and by the action of the coil spring 32 arranged coaxially with the locking pin 31, When the locking pin 31 moves in a direction away from the attachment hole of the blade 35 and the slit 20b, the blade 35 becomes detachable from the plunger 20.

  FIG. 4 is a cross-sectional view for explaining the principle of rotation of the blade holder 23, and (1) is a view showing a connection state between the blade holder 123 and the plunger 120 in the conventional example, and (2) to (4). These are figures which show the blade holder 23 and plunger 20 which concern on this embodiment. In the conventional example shown in FIG. 4 (1), a mounting portion 120 a with a reduced diameter is formed at the tip of the plunger 120. The attachment portion 120 a has a substantially rectangular cross section in the longitudinal direction and has a planar shape whose upper and lower surfaces are parallel, and the surface is in close contact with the inner wall in the vertical direction of the blade holder 123. Therefore, the blade holder 123 is held so that rattling does not occur with respect to the plunger 120. In the conventional example, the blade holder 123 and the plunger 120 are fixed by bolts (not shown) using not only the stepped holes 120c but also the knob fixing holes 120d.

  In the present embodiment, as shown in FIG. 4 (2), the basic shape of the blade holder 23 is the same as that of the conventional example, but two angle adjusting bolts 28a and 28b are provided in the vertical direction. Is different. The bolts 28a and 28b are attached to a screw hole 23b provided in the vertical direction and formed with a screw thread (female). On the other hand, the plunger 20 to be inserted into the blade holder 23 is the same as the conventional example in that a mounting portion 20a having a thin tip is formed, but the shapes of the upper and lower surfaces thereof are different. That is, in the mounting portion 20a, the upper and lower plane portions are formed so that the vertical width gradually increases from the tip (front end) (planar portion a), and the vertical width is the widest in the stepped hole 20c. (Top portion b), an upper and lower plane portion is formed such that the width in the vertical direction becomes narrower toward the rear than the stepped hole 20c (plane portion c).

  By forming these flat portions a and c obliquely, as shown in FIG. 4 (3), when the blade holder 23 is attached, the top portion b is formed between the attachment portion 20a of the plunger 20 and the blade holder 23. Except for the gap. However, by adjusting the tightening degree of the bolts 28a and 28b, the tips of the bolts 28a and 28b make good contact with the flat surface portion c of the mounting portion 20a, and the blade holder 23 is stably held with respect to the plunger 20. . Further, by loosening the lower bolt 28b of the blade holder 23 and tightening the upper bolt 28a, the blade holder 23 can be rotated in the direction of the arrow in FIG. At this time, the lower plane portion c and the upper plane portion a of the attachment portion 20 a are in good contact with the inner wall of the blade holder 23.

  FIG. 5 is a cross-sectional view showing a state where the blade 35 is actually attached. (1) shows a state where the blade holder 23 is not inclined, and (2) shows a state where the blade holder 23 is inclined downward. . In FIG. 5A, since the bolts 28a and 28b are tightened equally, the blade 35 is attached to the plunger 20 so that the inclination angle of the tooth surface is 3 degrees. On the other hand, when the lower bolt 28b is loosened and the upper bolt 28a is tightened to the maximum, the tooth surface of the blade 35 rotates about an angle of about 6 degrees with respect to the horizontal line as shown in FIG. As a result, the blade 35 has a tooth surface inclination angle of 9 degrees. Although not shown, conversely, when the upper bolt 28a is loosened and the lower bolt 28b is tightened to the maximum, the tooth surface of the blade is at an angle of -3 degrees with respect to the horizontal line. Will be held.

  As described above, since the blade 35 is locked by the upper and lower parallel portions of the inner wall of the blade holder 23, the relative angle between the plunger 20 and the blade 35 can be adjusted by rotating the blade holder 23. It becomes. As a result, by making it possible to arbitrarily adjust the angle of the blade 35 in accordance with the material to be cut 36, it is possible to efficiently perform the cutting operation even when a blade having no angle is used. For example, if the inclination angle of the tooth surface of the blade 35 is set to zero or set to a small value, the cutting speed becomes slow, but the vibration accompanying the cutting decreases. Conversely, if the inclination angle of the tooth surface is increased, the cutting speed can be increased although the vibration associated with the cutting increases.

  Next, a second embodiment of the present invention will be described with reference to FIG. In FIG. 6, unlike the first embodiment, the plunger is divided into two parts. That is, it comprised with the 1st plunger 40 and the 2nd plunger 41, and it comprised so that the 2nd plunger 41 could be rotated with respect to a 1st plunger as an adjustment function of the angle of the braid | blade 35. FIG. The principle of rotation of the second plunger 41 is basically the same as the rotation mechanism of the blade holder 23 of the first embodiment, and the second plunger 41 is provided with bolts 48a and 48b for rotation locking. One each was provided up and down. By adjusting the upper and lower bolts 48a and 48b, the angles of the first plunger 40 and the second plunger 41 can be adjusted. In the second embodiment, the center point of rotation is the mounting hole 40b formed in the mounting portion at the tip of the plunger 40, and is not rotated around the round hole 35c of the blade 35. Different from the first embodiment.

  As is apparent from the above description, according to the present invention, by changing the angle between the plungers 20 and 40 and the blade 35, the cutting speed can be improved by about 20% at maximum compared to the case where the angle is not changed. It was. Further, by making it possible to arbitrarily adjust the angle of the blade 35 in accordance with the material to be cut, it has become possible to efficiently perform the cutting operation even when a blade without an angle is used.

  As mentioned above, although demonstrated based on embodiment which shows this invention, this invention is not limited to the above-mentioned form, A various change is possible within the range which does not deviate from the meaning. For example, in the present embodiment, the bolts 28a, 28b, 48a, and 48b are configured to be tightened in the vertical direction of the plunger. However, the bolts 28a, 28b, 48a, and 48b may be configured to be tightened from the left and right directions instead of the vertical direction.

It is sectional drawing which shows the whole saver saw which concerns on the embodiment of this invention. It is a partial side view which shows the plunger 20 and blade holding | maintenance means of the saver saw of FIG. It is a side view of the blade holder 23 which employ | adopted the attachment angle changing means of the braid | blade which concerns on this embodiment, (1) is a side view, (2) is sectional drawing of the (A) AA part of FIG. It is sectional drawing for demonstrating the principle which the blade holder 23 rotates, (1) is a figure which shows the connection condition of the blade holder and plunger in a prior art example, (2)-(4) concerns on this embodiment. It is a figure which shows the blade holder 23 and the plunger 20. FIG. It is sectional drawing which shows the state which attached the braid | blade 35, (1) shows the state which does not incline the blade holder 23, (2) shows the state in which the blade holder 23 was inclined below. It is a figure which shows the plunger 20 and blade holding | maintenance means of a saver saw which show the 2nd Embodiment of this invention, (1) is a side view when not making it incline, (2) is a side view of (1). It is a figure which shows a partial cross section, (3) is a figure which shows a partial cross section by the side view at the time of making it incline. It is a side view which shows the braid | blade attached to a saver saw.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric motor 2 Motor housing 3 Handle 4 Switch 5 Inner cover 6 Gear cover 7 Motor shaft 8 Drive gear 9 Second shaft 9a Inclined shaft part 10 Driven gear 11 Subshaft 16 Base 17 Bearing 18 Reciprocating plate 18a (Reciprocating plate) swinging shaft Part 18b Spherical part (of reciprocating plate) 19 Bearing metal 20 Plunger 20a Mounting part 20b Slit 20c Stepped hole 20d Through hole 20e Hole part 21 Roller shaft A 22 Swing roller A 23 Blade holder 24 Knob 26 Knob cover 27 Fastening bolts 28a, 28b Bolt 29 Mounting bolt 30 Torsion coil spring 31 Locking pin 32 Coil spring 33 Front cover
34 Track surface A 35 Blade 35a (Blade) holding part
35b (blade) cutting teeth 35c (blade) round hole 36 material to be cut 40 first plunger
40a (first plunger) mounting portion 40b (first plunger) mounting hole 41 second plunger 42 fastening bolt 43 blade holder 46 knob cover 48a, 48b bolt 120 plunger 123a mounting portion 120c stepped hole 120d hole 123 blade holder

Claims (8)

A motor, a motion converting means for converting the rotational motion of the motor into a reciprocating motion of the plunger, a housing for housing the motor and the motion converting means, and a blade holding means for holding the blade attached to the tip of the plunger; In Saverso,
A saver saw provided with a mounting angle variable means for changing a mounting angle of the blade with respect to the plunger.   2. The saver saw according to claim 1, wherein the mounting angle varying unit is configured integrally with the blade holding unit and rotates the blade with respect to the plunger around a round hole formed in the blade. .   The saver saw according to claim 2, wherein the attachment angle varying means includes a pair of screws provided in the vertical direction of the blade holding means, and the rotation angle is changed by the screws.   At the tip of the plunger, a small-diameter mounting portion inserted into the blade holding means is formed, and above and below the mounting portion, the blade holding means is rotated around a round hole formed in the blade. 4. The saver saw according to claim 3, wherein an inclined surface is formed so as to make it possible.   The saver saw according to claim 4, wherein a distance between an inner wall of the blade holding means and the inclined surface is adjusted by abutting a tip of the screw with the inclined surface.   The mounting angle varying means is a second plunger provided between the blade holding means and the plunger, and the second plunger is a slight angle about a rotation axis perpendicular to the reciprocating direction of the plunger. The saver saw according to claim 1, wherein the saver saw is only rotatable.   The second plunger has an inner housing portion for inserting a small-diameter attachment portion formed at the distal end of the plunger, and an attachment portion protruding toward the distal end side for holding the blade holding means. The saver saw according to claim 6.   The second plunger has two screws from the vertical direction perpendicular to the rotation shaft, and the relative rotation angle between the two plungers is changed by adjusting the screws. The saver saw according to claim 7.

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