JP2000291762A - Reciprocating mechanism and electric tool using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a reciprocating mechanism with a simple and compact structure. SOLUTION: Two grooves 16, 16 are slantingly receessed on the outer periphery of the slide part 14 of a slider 12 whose rotation is regulated and steel balls 18, 18 in the through holes 17, 17 of a rotary sleeve 10 are in the grooves 16, 16 at the most rear position. Two second grooves 21, 21 are slantingly recessed on the outer periphery of the rotary sleeve 10, too and the steel balls 23, 23 in the through hole 22, 22 of the second slider 19 externally equiped to the rotary sleeve 10 are fitted in the second grooves 21, 21 at the most rear position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reciprocating mechanism for converting the rotational movement of a rotary drive source such as a motor into a reciprocating movement of a slider, a reciprocating saw using the reciprocating mechanism,
The present invention relates to a power tool such as a jigsaw and a hammer.

[0002]

2. Description of the Related Art A reciprocating mechanism is disclosed in Japanese Unexamined Patent Publication No. Hei.
Japanese Unexamined Patent Application Publication No. 18-18183 discloses a known one. This is because vibration occurs with the reciprocating movement of the slider, and in electric tools such as reciprocating saws, cutting accuracy and operability are reduced, so that the counter weight can be slid freely on the sleeve in which the slider is inserted. A primary wobble plate connected to the slider while supporting the auxiliary shaft that is rotationally transmitted from the motor in parallel with the slider, and
The secondary wobble plate connected to the count weight can be driven in the opposite direction with the rotation of the counter shaft, and vibration can be eliminated by reciprocating the count weight in the opposite direction to the reciprocation of the slider It is what it was.

[0003]

However, in the reciprocating mechanism described above, the size in the width direction is increased by the use of the countershaft, which results in an increase in the size of a power tool such as a reciprocating saw. In addition, since the number of components is increased by using the countershaft and the wobble plate, the assembling work is increased and the manufacturing cost is increased.

Accordingly, an object of the present invention is to provide a simpler and more compact reciprocating mechanism. And the invention according to claim 4 is:
An object of the present invention is to provide a power tool that can improve machining accuracy and operability with low vibration using such a reciprocating mechanism.

[0005]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a tubular body which is rotationally transmitted from a rotary drive source, and controls a rotation of the slider to the tubular body. Insert or exterior in the state, the cylindrical body and the slider,
The ball provided integrally with one of them and the ball provided on the other are fitted with each other, and connected by a ring-shaped groove inclined from the axis of the cylindrical body, with the rotation of the cylindrical body. The slider can reciprocate by moving the ball in the groove.
According to a second aspect of the present invention, in addition to the object of the first aspect, a pair of sliders are provided in the axial direction of the cylindrical body in order to reduce vibrations caused by reciprocating movement of the slider, and the rotation of the cylindrical body is reduced. Accordingly, the two sliders are reciprocated in opposite directions. According to a third aspect of the present invention, in addition to the object of the first or second aspect, in order to more effectively realize vibration reduction, an elastic means for supporting the cylindrical body in the axial direction is provided. In order to achieve the above object, the invention according to claim 4 uses the reciprocating mechanism according to any one of claims 1 to 3 to transmit the rotation of the motor to the cylindrical body, and This is an electric tool that transmits reciprocating motion to the tool side.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. << Embodiment 1 >> FIG. 1 is a partial vertical cross-sectional explanatory view of a reciprocating saw. In the reciprocating saw 1, a motor shaft 4 of a motor 3 housed in a motor housing 2 is a motor housing 2
The shaft 8 protrudes into the main body housing 5 connected to the front (left side in FIG. 1), and the shaft 8 is
With the gear 7 which is axially supported in parallel. Reference numeral 9 denotes a reciprocating mechanism provided in the main body housing 5. The front end of the shaft 8 of the gear 7 is press-fitted into the rear end of a rotary sleeve 10 as a cylindrical body in the reciprocating mechanism 9. The rotating sleeve 10 has a front end rotatably supported by a needle bearing 11 and rotates integrally with the gear 7. Inside the rotating sleeve 10, a slider 12 including a rod portion 13 and an axial slide portion 14 rotates. It is slidably accommodated in the axial direction. However, since the rod portion 13 is protruded at a position eccentric upward with respect to the slide portion 14 and penetrates the through hole 5a of the main body housing 5, the slider 12 slides only in the rotation sleeve 10 in the rotation restricted state. It becomes possible. Fifteen
Is a blade detachably attached to the tip of the rod portion 13.

Further, the slide portion 14 of the slider 12
On the outer circumference of the sliding member 14, two parallel grooves 16, 16 are recessed in a ring shape inclining from the axis of the slide portion 14, and the grooves 16, 16 are provided in the rotating sleeve 10 in the axial direction. Steel balls 1 stored in the through holes 17, 17
8, 18 are fitted. Since the cylindrical second slider 19 is rotatably and axially slidably mounted on the rotating sleeve 10, the steel balls 18, 18 are prevented from falling off by the second slider 19, and the grooves 16, 16 are always provided.
And the through holes 17, 17. The second slider 19 is penetrated by a shaft 20 protruding from the main body housing 5 in parallel below the rotary sleeve 10 and is restricted in rotation, and can only slide. Further, two parallel second grooves 21 and 21 are also provided on the outer periphery of the rotating sleeve 10 in a ring shape so as to be inclined from the axis of the rotating sleeve 10.
Through holes 22, 22 arranged in the second slider 19 in the axial direction
The steel balls 23, 23 housed in the housing are fitted. Steel balls 23, 2 in second slider 19
The sleeve 24 is prevented from falling out of the fitting portion 3 by the sleeve 24 because the sleeve 24 is restricted from moving in the axial direction. The fitting is performed over the holes 22 and 22.

In the reciprocating saw 1 constructed as described above, in the state shown in FIG. 1, both the steel balls 18, 18 and 23, 23 have the grooves 16, 16 and the second grooves 21, 21.
The slider 12 is at the forward position, and the second slider 19 is at the retracted position. From here, when the motor 3 starts to rotate rightward toward the front, the gear 7 meshing with the motor shaft 4 rotates leftward, causing the integral rotary sleeve 10 to rotate leftward. Accordingly, the steel balls 18, 18 rotate counterclockwise together with the rotating sleeve 10, and the slide portion 1 whose rotation is regulated.
4, the sliding portion 14 is retracted by the guide of the grooves 16 and 16 and the rotating sleeve 10 rotates half a turn. As shown in FIG. When the slider 12 reaches the frontmost position, the slider 12 reaches the retracted position. On the other hand, when the rotary sleeve 10 rotates left, the second grooves 21 and 21 also rotate left, and the steel ball 2
In order to advance 3, 23 along the second grooves 21, 21,
When the second slider 19 integrated with the steel balls 23, 23 moves forward and the rotary sleeve 10 makes a half turn, the steel balls 23, 23 reach the forefront positions of the second grooves 21, 21 as shown in FIG. The second slider 19 reaches the forward position.

When the rotary sleeve 10 further rotates half a turn from FIG.
1 to the advance position of FIG.
The second slider 19 is moved to the retracted position in FIG. 1 by the guides of the steel balls 23 and 23 and the second grooves 21 and 21, respectively. Numeral 19 denotes the forward and backward directions opposite to each other.
The reciprocating motion is performed with the movement amount moving in the 0 axis direction as a stroke. Here, the product of the weight of the slider 12 and its stroke is set to be substantially equal to the product of the weight of the second slider 19 and its stroke.

As described above, according to the reciprocating mechanism 9 of the first embodiment, the inclined grooves 16 and 21 and the steel balls 18 and 23 are provided.
The rotation of the rotary sleeve 10 can be converted into a reciprocating motion between the slider 12 and the second slider 19 with a simple configuration utilizing the fitting with the slider. In particular, since the slide portion 14 and the second slider 19 are reciprocated coaxially with respect to the rotary sleeve 10, space-saving and compactness can be achieved. Further, here, since the second slider 19 is reciprocated in the direction opposite to the reciprocating motion of the slider 12,
The two momentums in the axial direction cancel each other, and the vibration accompanying the reciprocating motion of the slider 12 can be effectively reduced. Therefore, according to the reciprocating saw 1 using the reciprocating motion mechanism 9, since the cutting operation by the blade 15 can be performed with low vibration, high cutting accuracy can be maintained and operability is improved. Further, simplification and downsizing of the reciprocating mechanism 9 leads to downsizing of the entire tool and reduction of manufacturing cost.

Here, two grooves 16 and two second grooves 21 are provided, respectively, to ensure the reciprocating movement of the slider 12 and the second slider 19 by fitting with the steel balls 18 and 23. By providing a plurality of such grooves at different inclination angles and selecting a groove into which a single steel ball is fitted, the stroke of the slider can be changed. In addition, the means for preventing the rotation of the slider 12 is not limited to the eccentricity of the rod 13,
The rod portion 13 and the slide portion 14 may be coaxially connected as long as the rod portion 13 itself can be prevented from rotating by key connection or spline connection with the a side. The same applies to the case of the second slider 19, which can be replaced by a key connection or a spline connection with the main body housing 5 side without depending on the penetration of the shaft 20.

<Embodiment 2> Next, another embodiment of the reciprocating mechanism will be described. Note that the same reference numerals as in the first embodiment denote the same parts, and a description thereof will be omitted. In the reciprocating motion mechanism 9a of the reciprocating saw 1a shown in FIG. 3, the front end of the rotary sleeve 10 is supported by a ball bearing 25, and the ball bearing 6 supporting the gear 7 connected to the front and rear ends of the ball bearing 25. O-rings 26 and 27 as elastic means are provided at the rear of the. Also, slider 1
The second and second sliders 19 each have one groove 16 and a steel ball 18, one second groove 21 and a steel ball 23, respectively.
And the slider 12
A shaft 28 fixed to the main housing 5 is loosely inserted in the axial direction in the slide portion 14 to strengthen the rotation stop. Further, the second slider 19 is a steel ball 1
And a slider body 30 having a through hole 22 into which a steel ball 23 is fitted. Is provided with a sleeve 31 for retaining the steel ball 23. On the other hand, the rotation stopper of the second slider 19 is provided with a guide groove 32 formed in the slider body 30 in the axial direction and a pin fixed to the body housing 5 and capable of being inserted into the guide groove 32 over the stroke of the second slider 19. 33.

Therefore, also in the reciprocating mechanism 9a of the second embodiment, when the rotary sleeve 10 makes a half turn from the forward position of the slider 12 and the retreat position of the second slider 19 shown in FIG. Retreats, the second slider 19 moves forward, and the reciprocating motion of the second slider 19 in the opposite direction to the reciprocating motion of the slider 12 is obtained as in the first embodiment. Therefore, as in the case of the first embodiment, it is possible to achieve simplification and downsizing of the configuration, and to reduce vibration associated with the reciprocating motion. In the reciprocating saw 1a using the reciprocating motion mechanism 9a, high cutting accuracy and good operability are maintained. As a result, it is possible to make the entire tool compact and reduce the manufacturing cost. In particular, in the second embodiment, the O-rings 26 and 27 are provided before and after the ball bearings 25 and 6 that support the rotating sleeve 10, so that a cushioning effect can be obtained in the axial direction, and more effective vibration prevention can be achieved. Become. Also, a ball bearing 25 is used for the shaft support of the rotating sleeve 10, and the groove 16 and the second groove 2 are used.
By setting 1 and 1 each, the dimension in the axial direction is reduced. Further, since the rotation of the second slider 19 is configured by the guide groove 32 and the pin 33, the main housing 5 is prevented from rotating.
Of the reciprocating mechanism 9a than in the first embodiment.
And the reciprocating saw 1a can be made compact. In addition, in the present embodiment, the needle ball 54 inserted between the sleeve 29 and the slider main body 30 makes it easy for the steel ball 18 retained on the sleeve 29 rotatably supported to roll to be easily rolled. There is also the advantage that operation can be obtained.

<Embodiment 3> In the embodiments 1 and 2, both the slider 12 and the second slider 19 are reciprocated by fitting the groove and the steel ball. good. This case is shown as mode 3. Reciprocating motion mechanism 9b of reciprocating saw 1b shown in FIG.
In the above, the slider 12 is formed into a hollow rod shape and is loosely inserted into a gear sleeve 45 as a cylindrical body which is supported by the ball bearing 6. And a gear 35 integral with the intermediate shaft 34 is meshed with the motor shaft 4,
The rotation of the intermediate shaft 34 has been obtained. In front of the intermediate shaft 34,
The large-diameter portion 36 is formed integrally with the axis inclined from the axis of the intermediate shaft 34. The large-diameter portion 36 is connected to the ring-shaped base end 41 of the connecting arm 40 via the ball bearing 39.
Is held. Also, the distal end portion 42 of the connecting arm 40
Penetrates through elongated holes 43, 43 formed above and below the slider 12, and at the same time, penetrates a columnar connecting body 44 inserted in the slider 12 in the left-right direction. Therefore, the slider 12 is connected to the connecting arm 40 and is also prevented from rotating.

On the other hand, the second slider 19 is
A ring-shaped groove 46 is provided on the outer periphery of the gear sleeve 45, and is provided in the outer periphery of the gear sleeve 45 so as to be inclined from its axis.
Is connected to the gear sleeve 45 by a steel ball 48 fitted to the gear sleeve 45. Reference numeral 49 denotes a sleeve for preventing the steel ball 48 from coming off at the outer periphery of the through hole 47, and reference numeral 50 denotes a counterweight extending downward to balance with the slider 12 side. The second slider 19 is prevented from rotating by a guide groove 51 formed in the upper surface in the axial direction and a pin 52 on the main body housing 5 side, and a slit is formed on the lower surface to avoid interference with the connecting arm 40. 5
3 are formed.

Therefore, in the third embodiment, when the motor shaft 4 rotates clockwise, the intermediate shaft 34 rotates counterclockwise via the gear 35. However, when the intermediate shaft 34 rotates half a turn from the state shown in FIG. 6, the connecting arm 40 holding the large-diameter portion 36 also swings to the opposite side, and the slider 12 connected to the distal end portion 42 is rotated.
Retreat. On the other hand, the gear sleeve 45 also rotates counterclockwise at the same time as the motor shaft 4 rotates clockwise.
The second slider 19 is advanced by the half rotation of the gear sleeve 45 as shown in FIG. Therefore, also in the reciprocating mechanism 9b according to the third aspect, the vibration can be effectively reduced by the reciprocating motion of the second slider 19 in the direction opposite to the reciprocating motion of the slider 12. In this embodiment, one side is formed by the intermediate shaft 34 and the connecting arm 40, and the other side is formed by the groove 46 and the steel ball 48, so that reciprocating motion is obtained. The number of parts is smaller than that using a pair of wobble plates (connection arms). Of course, even in the reciprocating saw 1b using the reciprocating mechanism 9b, high cutting accuracy and good operability due to low vibration can be maintained, and reduction in manufacturing cost can be realized.

In the first to third embodiments, the object in which the groove and the steel ball are provided between the cylindrical body and the slider may be reversed, or the insertion or exterior of the slider may be reversed left and right. Absent. In the first and second embodiments, a steel ball is provided for each slider. However, the steel ball is provided so as to protrude from both the inner and outer surfaces of the cylindrical body, and the inner surface is provided in the groove of one slider, and the outer surface is provided with the other ball. If they are fitted into the grooves of the slider, the steel balls can be shared, and the configuration can be further simplified. Furthermore, one slider is inserted into the cylindrical body and the other slider is externally mounted, but if there is a margin in the equiaxial direction where the stroke of the slider is small, both sliders are inserted or externally mounted on the cylindrical body. Is also good. In the third embodiment, if rotation is transmitted to the cylindrical body in front of the intermediate shaft,
The slide by the connecting arm and the slide by the tubular body can be reversed left and right.

[0018]

According to the first aspect of the invention, the rotation from the rotary drive source can be converted into the reciprocating motion of the slider with a simple configuration utilizing the fitting of the inclined groove and the ball. By making the slider and the slider reciprocate coaxially, it is possible to achieve space saving and compactness. Claim 2
According to the invention described in (1), in addition to the effect of the first aspect, the pair of sliders is reciprocated in opposite directions to each other, so that the axial momentums of both sliders cancel each other, and the Vibration accompanying reciprocation can be effectively reduced. According to the third aspect of the present invention, in addition to the effect of the first or second aspect, a cushion effect is obtained in the axial direction of the cylindrical body by providing the elastic means for supporting the cylindrical body in the axial direction. Therefore, more effective vibration prevention can be achieved.

According to the invention described in claim 4, according to claim 1,
By using any one of the reciprocating motion mechanisms of (1) to (3), an electric tool that transmits the rotation of the motor to the cylindrical body and transmits the reciprocating motion of the slider to the tool side can reduce the size of the entire tool and reduce the manufacturing cost. Reduction is possible. In particular, if the reciprocating mechanism of the second aspect is used, an effect of preventing vibration can be additionally obtained, and high machining accuracy and good operability can be maintained. The cushion effect by the elastic means is obtained, and more effective vibration prevention can be achieved.

[Brief description of the drawings]

FIG. 1 is a partial vertical cross-sectional explanatory view of a reciprocating saw of a first embodiment (a slider 12 is in a forward position).

FIG. 2 is a partial vertical cross-sectional explanatory view of the reciprocating saw according to the first embodiment (a slider 12 is in a retracted position).

FIG. 3 is a partial vertical cross-sectional explanatory view of a reciprocating saw according to a second embodiment (a slider 12 is in a forward position).

FIG. 4 is a partial vertical cross-sectional explanatory view of a reciprocating saw according to a second embodiment (a slider 12 is in a retracted position).

FIG. 5 is a partial vertical cross-sectional explanatory view of a reciprocating saw according to a third embodiment (a slider 12 is in a forward position).

FIG. 6 is a partial vertical cross-sectional view of the reciprocating saw according to the third embodiment (the slider 12 is in a retracted position).

[Explanation of symbols]

1, 1a, 1b reciprocating saw, 4 motor shaft, 5
..Main body housing, 9, 9a, 9b..reciprocating mechanism, 10.rotary sleeve, 12..slider, 13.
・ Rod part, 14 ・ ・ Slide part, 15 ・ ・ Blade,
16, 46 .. groove, 17, 22, 47 .. through hole, 18,
23, 48 steel ball, 19 second slider, 21 second groove, 26, 27 O-ring, 34
・ Intermediate shaft, 36 ・ ・ Large diameter part, 40 ・ ・ Connection arm, 45
..Gear sleeves.

Claims (4)

[Claims] 1. A reciprocating mechanism for converting a rotary motion from a rotary drive source into a reciprocating motion of a slider, comprising: a cylindrical body that is rotationally transmitted from the rotary drive source; Inserting or exteriorizing in a rotation-restricted state, the cylindrical body and the slider, a ball provided integrally with either one, the ball provided on the other, the ball fits, from the axis of the cylindrical body A reciprocating mechanism, wherein the slider is capable of reciprocating by being connected to an inclined ring-shaped groove and moving the ball in the groove as the cylindrical body rotates. 2. The reciprocating mechanism according to claim 1, wherein a pair of sliders are provided in the axial direction of the cylindrical body, and the two sliders reciprocate in opposite directions with the rotation of the cylindrical body. 3. The reciprocating mechanism according to claim 1, further comprising elastic means for supporting the cylindrical body in the axial direction. 4. An electric tool using the reciprocating motion mechanism according to claim 1 to transmit rotation of a motor to a cylindrical body and transmit reciprocating motion of a slider to a tool side.