JPH08155902A - Blade-mounting device for reciprocating cutting-tool - Google Patents

Abstract

PURPOSE: To obtain a blade-mounting device for a reciprocating cutting tool for cutting materials by reciprocating a blade as in a jig saw, wherein a blade can be mounted and dismounted without requiring any special tools, such as a bolt driver or a spanner, regardless of the type of the blade. CONSTITUTION: A blade mounting device comprises claws 40b, 40b for clamping a blade B, a driver rod 30 provided as claw-moving means for moving the claws 40b, 40b in the reciprocating directions of the blade B, and inclined surfaces 40e, 40e provided as claw operating means for opening and closing the claws 40b, 40b as the driver rods 30 moves.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blade mounting device for a reciprocating cutting tool such as a jigsaw or a reciprocating saw.

[0002]

2. Description of the Related Art Generally, in this type of tool, since the blade (blade) is replaced according to the plate thickness of the material to be cut,
The frequency of blade replacement is high. Therefore, when replacing the blade, there is a problem that it takes time and effort to operate the tool, and it is easy to lose the tool, in a configuration that requires a tool such as a spanner and a screwdriver. For this reason, it is desirable to use a tool that does not require a tool for blade replacement, and as a technique for this, there has been a blade mounting device disclosed in, for example, Japanese Patent Publication No. 3-503382.

In this conventional blade mounting apparatus, an end cap 107 is fixed to the tip of a drive shaft 103 that reciprocates in the axial direction, as shown in FIG. 9 which incorporates FIG. The cap 107 is provided with a pair of diametrically opposed inlet slots 108 and a pair of diametrically opposed retaining grooves 109. Holding groove 1
09 is provided at a position deviated from the inlet slot 108 by 90 ° in the circumferential direction. Further, a lock member 113 is provided on the inner peripheral side of the drive shaft 103 in a state of being vertically movable and biased downward by a compression spring 114. The lock member 113 is formed with a slot 112 into which a portion from immediately below the bayonet lug Ba of the blade B to the upper end Bt is inserted, and the upper end Bt of the blade B is brought into contact with the upper end of the slot 112. Thus, the blade B is biased downward by the compression spring 114. With such a configuration, the bayonet lug Ba is aligned with the inlet slot 108, the blade B is inserted into the slot 112 of the lock member 113, and then rotated by 90 ° to align the bayonet lug Ba with the holding groove 109. For example, the blade B is pressed downward by the compression spring 114, whereby the bayonet lug Ba is retained in the holding groove 109, and the blade B is attached so as not to come out. It should be noted that the lug 113 is also provided below the lock member 113.
a is provided so that the lug 113a fits into the inlet slot 108 when the blade B is attached, and the lock member 113 is locked so that it cannot rotate and thus the blade B does not rotate.

On the other hand, when removing the blade B, the locking member 113 is pulled upward by an unlocking operation of a lever or the like connected through the pulling member 118, thereby removing the lug 113a from the inlet slot 108, and thereby the compression spring 114. The pressing force of the blade B on the blade B is released, and the blade B is allowed to rotate. After that, the blade B can be removed by rotating the blade B by 90 ° and removing the bayonet lug Ba from the holding groove 109 while aligning with the inlet slot 108 and pulling out. And after removing
Insert another blade B and rotate it by 90 ° to align its bayonet lug Ba with the holding groove 109. After that, if the lever is locked, the blade B is moved downward by the compression spring 114 via the lock member 113. The blade B is pressed in the (removal direction), so that the bayonet lug Ba fits into the holding groove 109 and the other blade B is attached.

The above-mentioned configuration is disclosed in the publication as a first example. In addition to this, in the second example, the bayonet lug Ba of the blade B is held in a state of being fitted into the holding groove 109. The following configuration is disclosed as a means of.

That is, FIG. 10 which incorporates FIG. 5 of the publication.
As shown in, in this second example, a screw portion is formed on the inner peripheral surface of the hollow drive shaft 103, and the lock screw 128 is screwed inside the drive shaft 103 via this screw portion. A configuration is shown in which the head of the blade B is pressed or released by the forward / backward movement of the lock screw 128.
The lock screw 128 is provided with an extension 129 having a semicircular cross section and extending upward. On the other hand, a screw rotating member 130 having a semicircular cross section is formed inside the drive shaft 103 in a pair with the extension portion 129, with the extension portion 129 and the flat surface being in sliding contact with each other. . However, the screw rotation member 130 is not screwed onto the inner surface of the drive shaft 103.
Therefore, when the screw rotation member 130 is rotated via the operation knob 137, the extension portion 129 is also integrally rotated with it. The rotation of the extension 129 causes the lock screw 12
8 is also rotated integrally, and as a result, the lock screw 128 advances and retracts in the direction of pressing the upper end Bt of the blade B or in the direction of releasing it. At this time, since the screw rotating member 130 only rotates but does not move in the axial direction, the flat surface of the screw rotating member 130 and the flat surface of the extension portion 129 are in sliding contact with each other, and only the extension portion 129 is formed. Advancement and retreat are allowed.

[0007]

Conventionally, there has been provided a blade having such a structure that can be attached and detached without using a special tool.
In the above-described mounting device, the mountable blade is limited to the type having a protrusion (bayonet lug Ba) protruding laterally on its head, and other types cannot be mounted. This point is
First using lock member 113, compression spring 114, etc.
Example or lock screw 128 and rotary screw member 13
The same was true in any of the second examples using 0 and the like. That is, in this type of blade, in addition to the type in which the above projection is hooked to be attached so that it cannot be removed (hereinafter, also referred to as “projection type”), a hole is formed in the blade head,
There is a type in which a protrusion is fitted into this hole so that it cannot be pulled out (hereinafter referred to as "hole type"). However, the latter type does not have a portion to be engaged with the holding groove 109, so the above description is given. It cannot be mounted with the conventional mounting device.

Further, according to the same mounting device, the blade head is inserted and then rotated by 90 °, and the bayonet lug Ba is rotated.
Since it is necessary to align and engage with the holding groove 109, the mounting operation was troublesome.

The present invention has been made to solve the above-mentioned conventional problems in a reciprocating cutting tool which does not require a tool for attaching and detaching the blade, and it is not limited to the projection type but to the hole type or other types of blades. It is an object of the present invention to provide a blade attachment device that can be attached to and detached from the blade, and that can be attached and detached more easily without troublesome operations.

[0010]

Therefore, according to the first aspect of the present invention, a claw for sandwiching the blade, a claw moving means for moving the claw in the reciprocating direction of the blade, and a movement by the claw moving means. Accordingly, a claw opening / closing means for opening / closing the claw is provided.

[0011]

According to the structure of the first aspect, the blade is mounted by being sandwiched between the claws, so that the blade can be mounted regardless of the mounting type of the blade such as the projection type and the hole type. In addition, when the pawl moving means is operated in the pawl mounting direction for mounting, the pawl is closed and the blade is sandwiched, so that the blade is simply inserted between the pawls, and it is necessary to rotate the blade 90 ° after inserting the blade as in the conventional case. It is not necessary to apply the blade, and when removing, the claw moving means is only operated in the direction of removing the claw, and the pinching of the claw is released. Therefore, the blade may be detached as it is or simply pulled out from between the claws.

Moreover, since the pawl opening / closing means for opening / closing the pawl is provided, and the pawl opening / closing means operates in accordance with the movement of the pawl by the pawl moving means, it is necessary to install a blade or a driver in the conventional manner when attaching or detaching the blade. It is not necessary to use a special tool such as a spanner.

[0013]

According to the invention described in claim 1, the mounting and
No special tools are required for removal, and not only the projection type but also blade type blades and other mounting types can be attached, expanding the range of application and simplifying the attachment / detachment operation. Is improved.

[0014]

Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 shows a blade attaching device 10 of this example applied to a jigsaw. This blade mounting device 10 is roughly divided into a rod 2 that reciprocates.
0, a driver rod 30 arranged in the inner peripheral hole 20a of the rod 20 so as to be rotatable about the axis and movable in the axial direction, a claw 40 for sandwiching the blade B, and a claw 40 for opening and closing the claw 40. It is composed of a holder 50 for giving a motion. Hereinafter, each component will be described.

First, the rod 20 is reciprocally moved through a mechanism for converting the rotational output of the motor into a linear motion. This conversion mechanism in a jigsaw is known in the prior art, and there is no change in implementing the present invention. The description is omitted because it is not necessary. Although not shown, the rod 20 has a substantially cylindrical body, and is supported at the tip of the jigsaw body so as to be vertically reciprocable. A flat surface portion 20b is formed on the outer peripheral surface of the rod 20 substantially at the center in the axial direction, and a roller guide (not shown) having a U-shaped cross section that constitutes the conversion mechanism is axially formed on the flat surface portion 20b. Mounted orthogonally. This point is the same as the conventional one.

An inner peripheral hole 20a of the rod 20 is formed so as to penetrate therethrough, and a right-handed screw hole (hereinafter referred to as "right-handed screw hole") 20c is formed at a position in the axial direction at a certain position in the axial direction. . A circular flange portion 20e is formed at the tip of the rod 20.
On the front surface of e, the supporting wall portion 2 is provided with a certain space between the facing surfaces.
0d and 20d are formed to face each other in a substantially bifurcated shape. The inner peripheral hole 20a is opened between the support walls 20d, 20d and at the center of the flange 20e.

Next, in the claw 40, the claw parts 40b, 40b are formed at the tip of the cylindrical body part 40a so as to face each other in a bifurcated manner. An inclined surface 40e is formed in the sharpened tip direction at an angle. A concave portion 40f is provided between the base portions of the both claw portions 40b so as to apply elastic force in the opening direction to the both claw portions 40b.
The cut is formed at 0a. Further, a slit 40d is formed along the longitudinal direction at the center of the claw portions 40b in the width direction. The width of both claws 40b is the same as the rod 20 described above.
The width is such that it can enter between both support wall portions 20d, 20d. The cylindrical portion 40a is axially movably inserted into the inner peripheral hole 20a of the rod 20, and has a left-handed screw hole (hereinafter referred to as "left-handed screw hole") 4 on its rear end surface.
0c is formed. Claw 40 formed in this way
Inserts the cylindrical body portion 40a into the inner peripheral hole 20a of the rod 20, and thereby the claw portion 40b is inserted into the support wall portions 20d, 20d.
It is movably supported in the axial direction at the position inserted between
The tip of the driver rod 30 is screwed into the left screw hole 40c on the rear end surface. In the claw 40 of this example configured in this way, the both claw portions 40b, 40b correspond to the claws described in the claims.

The driver rod 30 has a diameter such that it can be inserted into the inner peripheral hole 20a of the rod 20, and its tip is
A right-handed screw portion (hereinafter referred to as “right-handed screw portion”) 30a and a left-handed screw portion (hereinafter referred to as “left-handed screw portion”) 30b are formed coaxially.
It has a smaller diameter than a and is formed on the tip side. A semicircular section of the driver rod 30 is missing above the right-hand threaded section 30a, and the semicircular rod section 30 has a semicircular section.
It is assumed to be c. The driver rod 30 formed in this way is inserted into the inner peripheral hole 20a from the rear end side of the rod 20, and the right screw portion 30a thereof is screwed into the right screw hole 20c on the inner peripheral hole 20a side, so that the left The screw part 30b is the right screw hole 2
It passes the inner circumference side of 0c and is located on the tip side of it,
At this position, it is screwed into the left screw hole 40c of the claw 40 as described above.

With such a configuration, when the driver rod 30 is rotated clockwise, the screwing action of the right screw portion 30a into the right screw hole 20c causes the driver rod 30 itself to rotate and move toward the distal end side in the axial direction. Advance. Moreover, when the driver rod 30 is rotated clockwise, the left screw portion 30b is anti-threaded into the left screw hole 40c of the pawl 40, and the pawl 40 does not rotate. Therefore, the driver rod 30 is displaced in the same direction. To do. As described above, when the driver rod 30 is rotated clockwise, the driver rod 30 is moved forward and the claw 40 is also moved forward with respect to the driver rod 30. As a result, the forward distance of the claw 40 is It is given as the sum of the advance distance of the driver rod 30 itself and the advance distance of the pawl 40 with respect to the driver rod 30. According to this, the pawl 40 can be greatly advanced by a slight rotation operation of the driver rod 30, As a result, the blade B can be chucked by closing the claw 40 with a slight operation as described later.

On the contrary, when the driver rod 30 is rotated counterclockwise, the driver rod 30 itself is moved to the right screw portion 30a.
Is retracted by the anti-screw action with respect to the right screw hole 20c, and the claw 40 is retracted with respect to the driver rod 30 by the screw action of the left screw portion 30b with respect to the left screw hole 40c. The claw 40 can be largely retracted so that the claw 40 can be opened and the blade B can be unchucked.

Thus, the rod 20 and the driver rod 3 are
0 and the driver rod 30 and the claw 40 are connected to each other via screws in the opposite directions, so that the claw 40 can be greatly opened and closed by a slight rotation operation of the driver rod 30. From this, the driver rod 30 and the right screw portion 30a, the left screw portion 30
b, the right screw hole 20c of the rod 20 and the claw 40
The left-handed screw hole 40c constitutes the pawl moving means described in the claims.

Next, a holder 5 for holding the claw 40 at the tip of the rod 20, that is, between the support walls 20d, 20d.
0 will be described. This holder 50 is formed in a substantially bowl shape so as to cover the tip of the claw 40, and an insertion port 50a through which the head of the blade B can be inserted is formed at the center thereof. In addition, as shown in FIG.
Is closed by the flange portion 20e of the rod 20 on the rear opening side (the side opposite to the insertion port 50a).
retaining ring 50 with d, 20d and claw 40 accommodated.
It is attached by b.

Now, in the inner surface of the holder 50 and in the vicinity of the insertion port 50a, inclined surfaces 50c, 50c are formed facing each other. Both inclined surfaces 50c, 50c
Are formed to incline in the tip sharpening direction at the same angle corresponding to the inclined surfaces 40e of the both claw portions 40b. Therefore, the inclined surfaces 40e of the claws 40b are in contact with the inclined surfaces 50c, respectively. When the claws 40 are advanced by the cooperation of the paired inclined surfaces 40e and 50c, the claws 40b are advanced. When the claws 40b and 40b are closed and the claw 40 is retracted, the claw portions 40b and 40b return to the opening direction by the elastic force. In this way, both inclined surfaces 50 of the holder 50
c and 50c serve to open and close the claws 40b and 40b of the claw 40, and the inclined surfaces 50c and 50c of the holder 50 correspond to the claw opening and closing means described in the claims. To do.

A mechanism for rotating the driver rod 30 will be briefly described below. A rotary rod 60 having a semicircular cross section is also provided above the driver rod 30 corresponding to the semicircular rod portion 30c. The rotary rod 60 is supported so as to be rotatable about the same axis, and the rotary rod 60 is slidably in contact with the flat portion of the semicircular rod portion 30c of the driver rod 30 so that the rotary rod 60 has an inner peripheral hole. 20a (the rotary rod 60 corresponds to the rotary screw member 130 in FIG. 8, and the semicircular rod portion 30c
Corresponds to the extension 129). Therefore, the rotating rod 6
When 0 is rotated, the flat portions are in contact with each other, so that the driver rod 30 is also rotated integrally. However, since the flat surface portions of the both 30c and 60 are merely in contact with each other, the driver rod 30 can independently move in the axial direction, and the rotating rod 60 does not move in the axial direction. Although not shown, a rotary operation knob is attached to the upper end of the rotary rod 60. By rotating this knob, the rotary rod 60 and thus the driver rod 30 are rotated clockwise or counterclockwise. It can be done.

According to the blade mounting apparatus 10 of the present embodiment constructed as described above, the blade B is mounted / removed as follows. FIG. 2 shows a state in which the blade B is removed. In this state, the claw 40 retracts upward and both claw portions 40b, 40b are opened. Now, with both the claws 40b, 40b open in this way, the head of the blade B to be attached is inserted between the two claws 40b, 40b via the insertion port 50a. When the knob for rotation operation is rotated clockwise while keeping this inserted state, the driver rod 30 rotates clockwise together with the rotating rod 60. When the driver rod 30 rotates clockwise, the driver rod 30 advances due to the screwing action of the right screw portion 30a into the right screw hole 20c as described above. At this time, the semicircular rod portion 30c is connected to the rotary rod 6
It deviates from 0 in the axial direction.

Further, the claw 40 has both supporting wall portions 20d, 20d.
Since it cannot be rotated because it is sandwiched between the claw 40 and the left screw part 30b, the claw 40 is not screwed into the left screw hole 40c.
Is advanced relative to the driver rod 30. From this, the claw 40 moves forward with respect to the driver rod 30 by the screwing action on the right screw hole 20c of the right screw part 30a and the driver rod 30 of the claw 40 by the anti-screw action on the left screw hole 40c of the left screw part 30b. Since the rod 20 is advanced by the total amount of the advance distance, that is, the inclined surface 50c of the holder 50, the pawl 40 can be greatly advanced by a slight operation amount of the rotary operation knob. When the claw 40 is moved forward with respect to the inclined surface 50c, the claw portions 40b, 40b are moved to the inclined surface 40e.
And the inclined surface 50c are gradually displaced in a direction in which they are mutually closed, whereby the head of the inserted blade B is sandwiched, and the blade B is chucked as described above. This state is shown in FIGS. 3 and 4.

To remove the blade B thus attached, the rotary operation knob may be operated in the opposite direction. As a result, the driver rod 30 is rotated counterclockwise, and thus the claw 40 is screwed into the left screw hole 40c of the left screw portion 30b and the backward distance of the driver rod 30 due to the anti-screw action of the right screw portion 30a with respect to the right screw hole 20c. The claw 40 is retracted with respect to the rod 20 by a total distance of the retracted distance of the claw 40 with respect to the driver rod 30. When the pawl 40 is retracted, the both pawl portions 40b are released from the restraint of the inclined surface 50c, and thus are reliably returned to the opening direction by the elastic force thereof. When both the claws 40b, 40b are opened, the blade B can be dropped as it is, or can be easily removed by simply pulling it out.

In this way, by rotating the rotary operation knob, the pair of claws 40b, 40b can be opened and closed to attach and detach the blade B. Therefore, a special tool such as a screwdriver or a spanner is used. It is possible to install and remove the blade without using it.

Moreover, since the blade B is sandwiched between both the claw portions 40b, 40b and is attached, the blade type is not limited to the projection type, and a blade type or other type can be attached. Claw portion 40b,
Any blade having a head that can be inserted between 40b can be mounted regardless of the mounting mode.
In addition, since it is configured to be sandwiched, the blades B having various plate thicknesses can be mounted without being restricted by the plate thickness within a certain range. FIG. 5 shows a state in which a blade B ′ having a thinner plate thickness than that shown in FIG. 3 is attached.

Further, it is not necessary to rotate the head 90 ° after inserting the head as in the conventional case.
Since only the operation of inserting between b or pulling out from between the two claw portions 40b, 40b is sufficient, the attaching / detaching operation becomes simple and therefore the usability thereof is improved.

Next, FIGS. 6 and 7 show a blade mounting device 11 of the second embodiment. In this blade mounting device 11, the screw parts 30a and 30b of the driver rod 30 in the blade mounting device 10 of the first embodiment are made to face in opposite directions, and the inclined surfaces 40e of the claw parts 40b and 40b,
The direction of 40e is the opposite, that is, the inclined surface in the tip opening / spreading direction, and both inclined surfaces 50c of the holder 50,
50c is also configured as an inclined surface in the tip opening / spreading direction. That is, a left screw portion 31a is formed at the tip of the driver rod 31, and a right screw portion 31b is formed at the tip of the left screw portion 31a. The left screw portion 31a is screwed into the left screw portion 21c formed on the inner circumference of the rod 21, and the right screw portion 31b is screwed into the right screw hole 41c formed in the cylindrical body portion 41a of the claw 41. This claw 41
Has bifurcated claw portions 41b, 41b.
On the back surface of 41b, there are slanted surfaces 41e in the direction of tip expansion and expansion.
Are formed. On the other hand, corresponding to this, the holder 51 is formed with the inclined surfaces 51c, 51c in the front end expanding direction, and the inclined surfaces 41e of the claw portions 41b are in sliding contact with each other.

According to the structure of the second embodiment, when the operation knob is rotated clockwise, the driver rod 31 and the rod 21 are connected to each other via the left screw, so that the driver rod 31 is connected to the rod 21. While retreating upwards,
Since the driver rod 31 and the claw 41 are connected via a right screw, the claw 41 retreats upward with respect to the driver rod 31, and eventually the claw 41 has the same retreat distance of the driver rod 31 as in the first embodiment. The pawl 41 is retreated by the total retreat distance with respect to the driver rod 31, so that the pawl 41 can be largely retracted by a slight rotation of the driver rod 31.

Then, both inclined surfaces 41e, 41e of the claw 41
Is inclined in the tip opening / expanding direction, and correspondingly the inclined surface 51c of the holder 51 is also inclined in the tip opening / expanding direction. Therefore, when the claw 41 is retracted upward as described above, both claw portions 41
b and 41b are closed, so that both claws 41b and 41b are closed.
The blade B inserted between b is chucked. vice versa,
By slightly rotating the operation knob counterclockwise, both claws 4
Blades B can be removed by widening 1b and 41b. As described above, in the first embodiment, the blade B is sandwiched and mounted by advancing the claw 40, whereas in the second embodiment, the blade B is sandwiched and mounted by retracting the claw 41. With this configuration, the same operational effect as that of the first embodiment can be obtained.

In the second embodiment, the holder 51 is also modified as shown in the figure.
That is, in the holder 51, the upper half in FIG. 6 is a cylindrical body portion 51a having a cylindrical shape, and the lower half is a prismatic cylindrical body portion 51b as well shown in FIG. The cylindrical body portion 51a is fitted and fixed to the inner peripheral side of the rod 21, so that the holder 51 is attached to the rod 2
It is attached to the tip of 1. As described above, the holder 51 has a slim shape because it is not configured to be mounted using the retaining ring 50b as in the first embodiment, and thus the mounting device 11 is compact and simple. Further, since the retaining ring 50b is not used, the number of parts is reduced, and the assembling property and the cost are improved.

On the other hand, the claw portions 41b, 41b are housed in a rectangular cylindrical body portion 51b, and the inclined surfaces 51c, 51c are formed on the inner walls of the cylindrical body portion 51b facing each other. The slanted surfaces 41e of the claw portions 41b are in sliding contact with each other. Moreover, both side surfaces of the claw portion 41b are slidably contacted with the other opposing inner walls 51d, 51d of the cylindrical body portion 51b, and these inner walls 51d, 51d function as the support wall portions 20d, 20d in the first embodiment. Have both. Therefore, the support wall portion 20d in the first embodiment,
20d is not provided, and also in this respect, the configuration of the mounting device 11 is simplified.

Next, a third embodiment will be described. In the third embodiment, as shown in FIG. 8, the claws 70 and 7 provided separately are provided.
1 is moved in the opposite direction to open and close its tip. That is, the both claws 70, 71 in this example correspond to the configuration in which the claw 40 in the first embodiment is divided at the center of the columnar body part 40a and the both claw parts 40b, 40b are separated. Therefore, the upper portions of both the claws 70, 71 have a semi-cylindrical shape, and the inner peripheral surfaces thereof are formed with right and left semi-circular screw holes 70a and 71a which are vertically displaced from each other as shown in the drawing. .

On the other hand, the driver rod 80 has
As in the first embodiment, a right screw portion 80a screwed into a right screw hole 20c formed on the inner peripheral surface of the rod 20 is formed,
A right screw portion 80b that is screwed only into the right screw hole 70a is formed on the tip side thereof, and a left screw portion 80c that is screwed only to the left screw portion 71a is formed on the tip side thereof.

Further, the back surface of the tip of the claw 70 is formed with an inclined surface 70b in the direction in which the tip is expanded, whereas the claw 7 is formed.
As in the first embodiment, an inclined surface 71b in the pointed tip direction is formed on the rear surface of the tip of No. 1, and correspondingly, the holder 90 has an inclined surface 90a in the tip expanding direction and an inclined surface 9 in the tip pointing direction.
0b are formed to face each other. Inclined surface 70b of claw 70
Is slidably in contact with the inclined surface 90a, and the inclined surface 71b of the claw 71 is in slidable contact with the inclined surface 90b.

With this structure, when the driver rod 80 is rotated clockwise by the rotation of the rotating rod (not shown) as in the first embodiment, the right-hand thread portion 80a is formed.
While the driver rod 80 moves forward by the screwing action of the right screw hole 20c, the claw 70 on the right side of the drawing retracts with respect to the driver rod 80 by the screwing action of the right screw portion 80b and the right screw hole 70a. Therefore, the right screw part 8
If the pitch (lead) of 0b is set to be larger than that of the right-hand threaded portion 80a, the claw 70 retracts relative to the rod 20. When the claw 70 is retracted, its tip end is displaced in the closing direction by the action of the inclined surface 70b and the inclined surface 90a of the holder 90. On the other hand, the anti-screw action of the left screw portion 80c and the left screw hole 71a causes the left claw 7 on the left side in the drawing.
1 is advanced with respect to the driver rod 80, and as a result, the claw 71 advances by the total distance of the forward distance of the driver rod 80 and the forward distance of the claw 71 with respect to the driver rod 80 (double speed action). When the claw 71 is moved forward, its tip portion is displaced in the closing direction by the action of the inclined surface 71b and the inclined surface 90b of the holder 90, and as a result, the tip ends of the both claws 70, 71 are slightly rotated by the driver rod 80. The part is closed and the blade B inserted between the two is sandwiched and attached.

On the contrary, when the driver rod 80 is rotated counterclockwise, the claw 70 on the right side in the figure advances while the claw 71 on the left side in the figure recedes, so that the tips of both claws 70, 71 are opened. Allows the blade to be removed.

As described above, according to the structure of the third embodiment, the blades can be attached / removed without using a special tool, and the blades of different attachment types can be attached, and the attachment / detachment operation can be simplified. Become.

Needless to say, each of the embodiments described above can be applied not only to the illustrated jigsaw but also to a reciprocating saw which is a reciprocating cutting tool of the same kind.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a blade attachment device according to a first embodiment of the present invention.

FIG. 2 is a front sectional view of a blade attaching device according to the first embodiment.

FIG. 3 is a front sectional view of the attachment device in a blade attachment state.

FIG. 4 is a side sectional view of the attachment device in a blade attachment state.

FIG. 5 is a front cross-sectional view of a mounting device in which a thin blade is mounted.

FIG. 6 is a front sectional view of a blade mounting device of a second embodiment.

FIG. 7 is a view on arrow A in FIG.

FIG. 8 is a front sectional view of a blade attaching device according to a third embodiment.

FIG. 9 shows a conventional blade mounting device, which is shown in Table 3
It is the figure which referred FIG. 2 of 503382 gazette.

FIG. 10 shows a conventional blade mounting device, which is shown in Table 3
It is the figure which referred to FIG. 5 of 503382 gazette.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Blade attachment device 20 ... Rod, 20c ... Right screw hole 30 ... Driver rod 30a ... Right screw part, 30b ... Left screw part, 30c ... Semicircular rod part 40 ... Claw, 40e ... Inclined surface 50 ... Holder, 50c ... Inclined surface 60 ... Rotating rod 41 ... Claw of the second embodiment, 51 ... Holder of the second embodiment 70, 71 ... Claw of the third embodiment 80 ... Driver rod of the third embodiment 80a, 80b ... Right screw part, 80c ... Left screw part 90 ... Holder, 90a, 90b ... Sloping surface B ... Blade

Front Page Continuation (72) Inventor Hideki Okubo 3-11-8 Sumiyoshi-cho, Anjo City, Aichi Prefecture Makita Corporation

Claims (1)

[Claims] 1. A claw for sandwiching a blade, claw moving means for moving the claw in the reciprocating direction of the blade, and claw opening / closing means for opening and closing the claw according to the movement by the claw moving means. A blade mounting device for a reciprocating cutting tool, which has a structure.