JP2007030314A - Portable circular saw - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique effective in the simplification of the structure of a locking mechanism for locking a circular saw main body at an initial position and an intermediate position in a portable circular saw. <P>SOLUTION: The portable circular saw 101 has: a main body locking mechanism 131 which regulates the relative movement of the circular saw main body 121 in relation to a base 111 by locking the main body when it is set at the initial position or the intermediate position set between the initial position and a downward position; and an unlocking means 155 for unlocking the main body locked by the main body locking mechanism. The main body locking mechanism has a movable member 141 which, at the intermediate position, is operated to be changed over between a locking allowance position allowing the locking of the circular saw main body and a locking prohibition position prohibiting the locking of the main body. When the movable member 141 is set at the locking allowance position, the main body is locked at the intermediate position to regulate its relative movement in relation to the base. When the movable member 141 is set at the locking prohibition position, the main body is not locked at the intermediate position and allowed to move between the initial position and the downward position. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  In the present invention, a circular saw body having a rotary saw blade is always placed at a top dead center position where the lower edge of the rotary saw blade has been moved above the base. In a portable circular saw of a type in which a workpiece can be processed by a rotary saw blade by moving the circular saw body from the initial position to a lower position where the lower edge of the rotary saw blade protrudes below the base. When the circular saw body is placed at the initial position and at an intermediate position (blade replacement position) set between the initial position and the lower position, the circular saw body is locked. Related to lock technology.

This kind of portable circular saw is disclosed in, for example, European Patent Publication No. 1,193,036 (Patent Document 1). Patent Document 1 describes a portable circular saw having a configuration in which a circular saw body having a rotary saw blade is connected to a base having a blade case so as to be pivotable in the vertical direction via a pivot shaft. . In this portable circular saw, the circular saw body is always placed at a top dead center position where the lower edge of the rotary saw blade is moved above the base and the entire saw blade is housed in the blade case. Then, with this top dead center position as the initial position, the circular saw body is moved from the initial position to a lower position where the lower edge of the rotary saw blade is below the lower surface of the base, so that the machining operation by the rotary saw blade can be performed. It is a format that is possible, that is, the depth of cut is set. This type of portable circular saw is sometimes referred to as a plunge circular saw or a plunge cut saw.
In the portable circular saw described in Patent Document 1, when the circular saw body is placed at the top dead center position, a top dead center locking mechanism that locks the circular saw body at the top dead center position, and energization of the motor is turned on. A switch lock mechanism for locking the switch to be turned off to the off position. In addition to the top dead center lock mechanism and the switch lock mechanism, when the circular saw body is placed at an intermediate position between the top dead center position and the lower position, the circular saw body is moved to the intermediate position as necessary. An intermediate locking mechanism that can be locked in position is provided. The intermediate position is set as a blade replacement position. The intermediate lock mechanism is placed in a state that prohibits the lock at the intermediate position of the circular saw body during normal machining operations, and switches to a state that enables the lock at the intermediate position of the circular saw body when replacing the blade. It is supposed to be configured. That is, the intermediate lock mechanism is used only when the circular saw body is locked in the intermediate position. When the circular saw body is locked at the intermediate position, the mounting flange that detachably fixes the rotary saw blade to the drive shaft is configured to face the working hole provided in the blade case. The rotary saw blade can be replaced by removing the mounting flange. The intermediate lock mechanism includes a shaft lock mechanism that locks the shaft of the rotary saw blade, and a switch lock mechanism that locks the switch for turning on / off the motor to the off position.

As described above, the portable circular saw described in Patent Document 1 includes a top dead center locking mechanism that locks the circular saw body at the top dead center position, and an intermediate locking mechanism that locks the intermediate saw (blade replacement position). There are two types of lock mechanisms, and these two types of lock mechanisms are switched and used properly. For this reason, there are a large number of components of the lock mechanism. As a result, there is a problem that the structure becomes complicated and the cost is high, and there is still room for improvement in this respect.
European Patent Publication No. 1,193,036

  In view of the above, an object of the present invention is to provide a technique effective in simplifying the structure of a lock mechanism for locking a circular saw body at an initial position and an intermediate position in a portable circular saw. .

In order to achieve the above object, the invention described in each claim is configured.
According to the first aspect of the present invention, the mobile phone includes a base having a blade case, and a circular saw body having a rotary saw blade for performing a machining operation on a workpiece and connected to the base so as to be relatively movable. A circular saw is constructed. The circular saw body is normally moved to the position where the lower edge of the rotary saw blade is moved above the base and the entire rotary saw blade is accommodated in the blade case. By moving the lower edge portion to a lower position protruding downward from the base, a machining operation using a rotary saw blade is enabled. In the present invention, “relatively movable connection” typically refers to a mode in which a circular saw body is connected to a base so as to be rotatable in a vertical direction via a rotation shaft. The embodiment suitably includes a mode in which the circular saw body is connected to the base so as to be linearly slidable in the vertical direction.
The portable circular saw configured as described above has a rotating saw blade by placing a base on a workpiece and then moving a circular saw body placed at an initial position from the initial position to a lower position. The lower edge of the workpiece can be moved below the base, and the workpiece can be cut by the lower edge of the rotary saw blade. In this case, the depth of cut by the rotary saw blade is appropriately set by changing the amount of protrusion of the rotary saw blade from the bottom surface of the base, that is, by adjusting the amount of relative movement from the initial position of the circular saw body to the base. can do.

  The portable circular saw according to the invention described in claim 1 is characterized in that the circular saw body is placed at an intermediate position set when the circular saw body is placed at the initial position and between the initial position and the lower position. A main body locking mechanism that locks the circular saw body and restricts relative movement with respect to the base, and a lock release means that can be operated to unlock the circular saw body by the main body locking mechanism. The main body lock mechanism has a movable member that is operated to switch between a lock allowable position that allows the circular saw body to be locked by the main body lock mechanism and a lock prohibition position that prohibits the lock at an intermediate position, and is movable. In a state where the member is placed in the lock allowable position, the circular saw body moved from the initial position or the lower position and placed in the intermediate position is locked to the intermediate position to restrict relative movement with respect to the base, and the movable member is locked. In the state where the circular saw body is placed in the prohibited position, the circular saw body is allowed to move between the initial position and the lower position without being locked at the intermediate position.

According to the present invention, when the workpiece is processed, the movable member of the main body lock mechanism is placed at the lock prohibition position, and the lock of the circular saw body by the main body lock mechanism at the intermediate position is prohibited. In this state, the circular saw body is allowed to move between the initial position and the lower position without being locked at the intermediate position. For this reason, after operating the lock release means to release the lock of the circular saw body by the main body lock mechanism in the initial position, the circular saw body is moved from the initial position to the lower position and the workpiece by the rotary saw blade is moved. Processing operations can be performed. On the other hand, when the movable member of the main body lock mechanism is placed at the lock permissible position, the circular saw body moved from the initial position or the lower position and placed at the intermediate position is locked to the intermediate position by the main body lock mechanism, and is fixed to the base. Relative movement can be restricted. The “intermediate position” in the present invention typically corresponds to a blade replacement position set to replace the rotary saw blade. Incidentally, in the blade replacement position, a mounting flange as a detachable member for mounting the rotary saw blade on the output shaft driven by the motor faces a work hole formed in the blade case that houses the rotary saw blade. Therefore, it is possible to attach and detach the rotary saw blade through the work hole.
Thus, according to the present invention, since the main body locking mechanism can be used at both the initial position and the intermediate position, in addition to the locking mechanism for the initial position, a dedicated mechanism for the intermediate position can be used. Compared to a conventional structure having a lock mechanism, the number of components of the lock mechanism can be reduced, and the structure can be simplified and the cost can be rationally reduced.

(Invention of Claim 2)
According to a second aspect of the present invention, in the portable circular saw according to the first aspect, the motor for driving the rotary saw blade, the power switch for turning on / off the motor, and the circular saw body at the initial position. And a power switch lock mechanism that locks the power switch in an off position that turns off the power to the motor when the power switch is placed and at an intermediate position. The power switch lock mechanism is configured such that when the lock of the circular saw body by the main body lock mechanism is released by operating the lock release means, the lock of the power switch is released simultaneously by the lock release means. Here, the “power switch” in the present invention typically corresponds to an electrical switch that is turned on / off by a trigger that is pulled by a user's finger. The “unlocking means” suitably includes, for example, an unlocking button that is operated linearly by a pressing operation with a user's finger, or an unlocking lever that is operated by a rotating operation with the user's finger. . According to the present invention, the unlocking of the circular saw body by the main body locking mechanism and the unlocking of the power switch by the power switch locking mechanism can be simultaneously performed by a common unlocking means, so the number of parts can be reduced. As a result, the work efficiency of the unlocking work is improved.

(Invention of Claim 3)
According to the third aspect of the present invention, the main body locking mechanism in the portable circular saw according to the first or second aspect is provided on the base side and corresponds to the first engaging recess and the intermediate position corresponding to the initial position. A second engaging recess that is provided on the circular saw body side and is movable in a direction approaching or separating from the first engaging recess or the second engaging recess. Alternatively, the lock member is provided with an urging force in a direction to approach the second engagement recess. When the circular saw body is placed in the initial position, the lock member moves in a direction approaching the first engagement recess by the urging force, and engages with the first engagement recess. Lock the saw body in the initial position. Further, when the circular saw body is placed at the intermediate position, the lock member moves in a direction approaching the second engagement recess via an urging force when the movable member is placed at the lock allowable position. Engage with the second engaging recess, thereby locking the circular saw body in the intermediate position, and in a state where the movable member is placed in the lock prohibiting position, the intermediate is not engaged with the second engaging recess. It is set as the structure which passes a position.

The “engagement recess” in the present invention broadly includes a recess, a hole, a notch, or the like with which the lock member can be engaged. The “locking member” in the present invention is, for example, a rod-shaped member, and is engaged with or separated from the engaging recess by moving linearly in a direction intersecting the moving direction with respect to the base of the circular saw body, or a lever shape. It preferably includes a mode of being engaged with or being separated from the engaging recess by rotating in a direction intersecting the moving direction with respect to the base of the circular saw body.
According to the present invention, the main body locking mechanism for locking the circular saw main body between the initial position and the intermediate position is constituted by the two engaging recesses and the one locking member, so that an inexpensive main body locking with fewer parts. A mechanism can be provided. In addition, since the lock member is constantly biased in the direction in which the lock member is engaged with the engagement portion, the first or the first operation is performed without any special operation when the circular saw body is placed at the initial position or the intermediate position. It engages with the second engaging recess and acts as a so-called automatic lock.

(Invention of Claim 4)
According to the fourth aspect of the present invention, the movable member in the portable circular saw according to the third aspect is rotatable between the lock allowable position and the lock prohibited position. When the movable member is rotated to the lock permissible position, the second engagement recess is placed in a state of receiving the engagement of the lock member with the second engagement recess and is rotated to the lock prohibition position. When operated, the second engaging recess is placed in a state of obstructing the engagement of the lock member with the second engaging recess. In the present invention, “obstructing the engagement” means, for example, a mode in which the movable member blocks part or all of the second engagement recess so that the lock member cannot be engaged with the second engagement recess. Say. According to the present invention, since the movable member is of the rotation type, the arrangement space can be easily secured and the engagement of the lock member with the second engagement recess is allowed in the region of the arrangement space of the movable member. It is possible to switch between a state and a disturbing state.

  According to the present invention, in the portable circular saw, a technique effective for simplifying the structure of the lock mechanism for locking the circular saw body at the initial position and the intermediate position is provided.

  Hereinafter, a portable circular saw according to an embodiment of the present invention will be described with reference to the drawings. 1 to 6 show an overall configuration of the portable circular saw according to the present embodiment as a perspective view seen from the front side or a perspective view seen from the back side. 1 and 2 show the state where the circular saw body is placed at the top dead center position, and FIGS. 3 and 4 show the state where the circular saw body is placed at the blade replacement position, respectively. FIG. 6 shows a state where the circular saw body is placed at the cutting position. 7 and 8 are front perspective views showing the circular saw body. However, the illustration of the blade is omitted. 9 is a rear perspective view showing a state where the circular saw body is locked at the blade replacement position, FIG. 10 is a rear perspective view showing a case where the circular saw body is not locked at the blade replacement position, and FIGS. 11 and 12 are blades. FIG. 13 is an exploded perspective view showing the movable disk mounting structure at the blade replacement position. FIG. 14 is an explanatory view showing the connection structure of the lock release button and the interlocking lever.

  As shown in FIGS. 1 to 6, the portable circular saw 101 according to the present embodiment generally includes a base 111 that can be placed on a workpiece, and a circular saw main body connected to the base 111. 121. The workpiece is not shown for convenience. The circular saw body 121 corresponds to the “circular saw body” in the present invention.

  As shown in FIGS. 1 to 6 or 7 and 8, the circular saw body 121 houses a blade 123 (see FIGS. 3 and 5) and a drive motor (not shown) for rotationally driving the blade 123. The motor housing 125 and the hand grip 127 for the user to operate and operate the portable circular saw 101 are mainly configured. The blade 123 is covered with a blade case 113 that is fixedly provided on the upper surface side of the base 111. The blade 123 corresponds to the “rotary saw blade” in the present invention. The circular saw body 121 is arranged on the upper surface side of the base 111 and is connected to the base 111 so as to be rotatable in the vertical direction via a rotation shaft (not shown) for convenience. Has been. 7 and 8 show a rotating cylinder portion 122 that is provided on the circular saw main body 121 side and is rotatably fitted to the rotating shaft. The drive motor is energized and driven by a pulling operation of a trigger 128 disposed on the hand grip 127.

  FIGS. 1 and 2 show a state in which the circular saw body 121 is rotated most upward about the rotation axis, that is, the circular saw body 121 is placed at the top dead center position. . The top dead center position corresponds to the “initial position” in the present invention. In this state, the circular saw body 121 is urged upward with respect to the base 111 by the compression coil spring 167, and the position is fixed by the contact between the base-side upper stopper 161 and the circular saw body-side stopper 163. In a state where the circular saw main body 121 is placed at the top dead center position, the blade 123 has its lower edge 123 a moved upward from the base 111 and is entirely housed in the blade case 113. . In this state, the portable circular saw 101 can be placed in a stable state in which the base 111 is leveled on the floor surface or the like.

  3 and 4 show a state in which the circular saw body 121 is rotated downward from the top dead center position and placed at the blade replacement position. The blade replacement position corresponds to the “intermediate position” in the present invention. In a state where the circular saw body 121 is placed at the blade replacement position, the mounting flange 124 that attaches the blade 123 to the blade shaft (not shown) faces the working hole 113a provided in the blade case 113 and the blade 123. The lower edge portion 123a slightly protrudes from the lower surface of the base 111. Therefore, at this blade replacement position, the attachment flange 124 can be removed through the work hole 113a of the blade case 113, and the blade 123 can be replaced.

FIGS. 5 and 6 show a state where the circular saw body 121 is further rotated downward from the blade replacement position and placed at the cutting work position. The cutting work position corresponds to the “downward position” in the present invention. The amount of protrusion of the blade 123 from the lower surface of the base 111 at this cutting work position, that is, the cutting depth, is appropriately set by changing the downward rotation angle of the circular saw body 121. The maximum cutting depth by the blade 123 is determined by the contact between the circular saw main body side stopper 163 and the base side lower stopper 165. Here, the base-side lower stopper 165 can be adjusted in the vertical direction by loosening the screw portion 165a, and can be fixed at an arbitrary position.
The portable circular saw 101 configured as described above is configured to rotate the blade 123 by energizing the drive motor by pulling the trigger 128 while the base 111 is placed on a workpiece (not shown). By rotating the circular saw body 121 downward from the top dead center position, the lower edge portion 123a of the blade 123 is moved below the base 111 to cut the workpiece at a predetermined cutting depth. Can do. Further, the portable circular saw 101 of the present embodiment is a type in which the blade 123 is positioned above the base 111 when the circular saw body 121 is placed at the top dead center position. Work can be done easily.

  The portable circular saw 101 according to the present embodiment locks the circular saw body 121 when the circular saw body 121 is placed at the top dead center position and when the circular saw body 121 is placed at the blade replacement position. And a lock mechanism 131 that restricts the rotation of the base 111 around the rotation axis. The lock mechanism 131 corresponds to the “main body lock mechanism” in the present invention. Hereinafter, the lock mechanism 131 for locking the circular saw body 121 will be described in detail. The lock mechanism 131 of the circular saw body 121 includes a first engagement recess 133 for the top dead center position provided in the blade case 113, and a second engagement recess 135 for the blade replacement position provided in the blade case 113. , And a lock pin 137 made of a round bar-like member provided in the circular saw body 121. The first engagement recess 133 corresponds to the “first engagement recess” in the present invention, the second engagement recess 135 corresponds to the “second engagement recess” in the present invention, and the lock pin 137 is This corresponds to the “lock member” in the present invention.

  The first engagement recess 133 and the second engagement recess 135 are formed in a concave shape on the upper edge side of the side wall surface 113b (the surface facing the circular saw body 121) of the blade case 113 (FIGS. 2, 4 and 4). (See FIGS. 6, 9, and 10). The second engagement recess 135 for the blade replacement position is a switching type that can be switched between an accepting state in which engagement of the stopper pin 137 is allowed and a disturbing state in which it is prohibited by a movable disk 141 as a switching member, When placed in the receiving state, engagement with the lock pin 137 is allowed. This will be described later.

  The lock pin 137 is attached to a pin receiving portion 125 a provided near the base of the hand grip 127 in the motor housing 125 so as to be linearly movable in a horizontal direction perpendicular to the rotational direction of the circular saw body 121, and the tip thereof is It faces the side wall surface 113b of the blade case 113. The lock pin 137 that rotates together with the circular saw body 121 has its tip opposed to the first engaging recess 133 when the circular saw body 121 is placed at the top dead center position. When 121 is placed at the blade replacement position, the tip thereof faces the second engagement recess 135. The lock pin 137 is constantly urged toward the side wall surface 113b of the blade case 113 by a compression coil spring 157 (see FIGS. 7 and 8) described later. For this reason, the lock pin 137 has a tip at the side wall surface of the blade case 113 when the trigger 128 and the lock release button 155 described later are not operated and when the circular saw body 121 is rotated in the vertical direction. It moves along the side wall surface 113b along the 113b. Then, at the same time as facing the first engagement recess 133 or the second engagement recess 135, the first engagement recess 133 or the second engagement recess 135 is engaged, whereby the circular saw body 121 is moved to the top dead center position or Lock to the blade replacement position. Thus, the lock mechanism 131 according to the present embodiment acts as a top dead center locking mechanism when the circular saw body 121 is placed at the top dead center position, and the circular saw body 121 is placed at the blade replacement position. When this occurs, it acts as an intermediate locking mechanism. That is, in the top dead center locking mechanism that locks the circular saw main body 121 at the top dead center in the lock mechanism 131, the circular saw main body 121 is automatically brought to the top dead center position by the compression coil spring 167 after the operation is completed. When returned to the top dead center position, the lock pin 137 is automatically engaged with the first engagement recess 133 by the compression coil spring 157. On the other hand, the intermediate lock mechanism that locks at the blade replacement position in the present lock mechanism 131 has the same effect as the top dead center lock mechanism, and is different in that an operation of the movable disk 141 described later is required.

  Next, the first engagement recess 133 and the second engagement recess 135, which are receiving members with which the lock pin 137 in the lock mechanism 131 is engaged, will be described. The first engaging recess 133 for the top dead center position is configured such that the lock pin 137 is necessarily engaged when the circular saw body 121 is moved to the top dead center position. On the other hand, the second engagement recess 135 for the blade replacement position is a switching type by a movable disk 141 as a switching member formed in a disk shape, and a receiving state that allows the engagement of the lock pin 137, It is possible to switch between disturbing states that prohibit engagement. The movable disk 141 corresponds to the “movable member” in the present invention.

  As shown in FIGS. 11 to 13, the second engagement recess 135 is formed in a substantially semicircular recess 135 a formed on the side wall surface 113 b of the blade case 113 and an outer periphery of the movable disk 141. It comprises a semicircular recess 135b. The movable disk 141 can be rotated about its center, and when the recess 135b is rotated to a position opposite to the case-side recess 135a, the second engagement recess 135 of the lock pin 137 is moved. When the circular receiving state (opening state shown in FIG. 11) allowing the engagement (insertion) is made and the outer peripheral area where the recess 135b does not exist is rotated to a position facing the recess 135a on the case side, The engagement recess 135 is in a substantially semicircular obstruction state (closed state shown in FIG. 12) that prohibits the lock pin 137 from engaging. That is, the movable disk 141 switches the second engagement portion between an engagement allowable position where the engagement of the lock pin 137 is permitted and an engagement prohibition position where the engagement of the lock pin 137 is prohibited. The engagement allowable position corresponds to the “lock allowable position” in the present invention, and the engagement prohibited position corresponds to the “lock prohibited position” in the present invention.

  The movable disk 141 is disposed in an accommodation recess 113c formed in the side wall surface 113b of the blade case 113, and is mounted so as to be rotatable around an axis center via a mounting screw 143 and a washer 145 shown in FIG. Yes. An engagement prohibition position where the outer peripheral region where the recess 135b does not exist is always opposed to the case-side recess 135a by the torsion spring 147 as an urging member and the engagement of the lock pin 137 with the second engagement recess 135 is obstructed. (Position shown in FIG. 12).

  Further, as shown in FIGS. 7 and 8, the portable circular saw 101 has a trigger lock mechanism 151 that locks the trigger 128 that is pulled to energize the drive motor so as not to be pulled. The trigger lock mechanism 151 corresponds to the “power switch lock mechanism” in the present invention. The trigger 128 is attached to the hand grip 127 so as to be rotatable about a shaft 128a so as to operate a power switch 129 for turning on / off the energization of the drive motor. The trigger 128 is held at a position where the power switch 129 is turned off by a spring (not shown) in a state where the trigger 128 is not pulled by the user's finger, and when the trigger 128 is pulled, the trigger 128 rotates around the shaft 128a. The power switch 129 is turned on. The power switch 129 corresponds to the “power switch” in the present invention.

  The trigger lock mechanism 151 is configured mainly with a lock claw 153 that abuts against the trigger 128 and restricts the pull operation with respect to the pull operation of the trigger 128, that is, locks the power switch 129 in the off position. The lock claw 153 is provided integrally with the shaft portion 155 a of the lock release button 155, and is always in contact with the upper surface portion 128 b of the trigger 128 and is locked at a position before the trigger 128 is pulled. This state is shown in FIG. The unlock button 155 is disposed in the hollow portion of the hand grip 127 so as to be linearly movable in the axial direction, and the head portion 155 b is exposed to the outside of the hand grip 127. The unlock button 155 corresponds to the “unlock means” in the present invention.

  When the lock release button 155 is pushed by the user, the lock claw 153 is moved to a position facing the escape hole 128c provided in the upper surface portion 128b of the trigger 128, and allows the trigger 128 to be pulled (lock). The claw 153 enters the escape hole 128c). This state is shown in FIG. The lock release button 155 is normally urged in a direction opposite to the pushing direction by a compression coil spring 157 as an urging member, whereby the lock claw 153 is held at a position where the trigger 128 is locked. The compression coil spring 157 is arranged loosely on the shaft portion 155 a of the lock release button 155, one end is locked to the lock claw 153, and the other end is locked to the hand grip 127.

  The lock release button 155 is connected to the lock pin 137 of the lock mechanism 131 that locks the circular saw body 121 described above via an interlocking lever 159. The interlocking lever 159 is disposed in the hollow portion of the handgrip 127 and is rotatable through a shaft 159a. One end of the interlocking lever 159 is a substantially circular shape formed at the tip of the shaft portion 155a of the lock release button 155. It is engaged with the end engaging portion 155d having a shape via a substantially U-shaped notch 159b (see FIG. 14). When the lock release button 155 is pushed, the interlocking lever 159 is pushed by the wall 159c of the notch 159b at the distal end portion of the distal end engaging portion 155d as shown by a two-dot chain line in FIG. And the lock pin 137 is moved in a direction in which the lock pin 137 is separated from the first engagement recess 133 or the second engagement recess 135, that is, in a direction in which the circular saw body 121 is unlocked. When the pushing force of the unlocking button 155 is removed and the unlocking button 155 is pushed back by the coil spring 157, the interlocking lever 159 has the tip engaging portion 155d of the unlocking button 155 as shown by a solid line in FIG. By pulling the inclined surface 159d of the notch 159b on the base side (root side) of the notch 159d, the inclined surface 159d is rotated in the opposite direction (direction indicated by the arrow in FIG. 7) by the action of the inclined surface 159d. The first engagement recess 133 or the second engagement recess 135 is moved closer to the direction. In other words, the lock pin 137 is biased by the coil spring 157 in a direction approaching the first engagement recess 133 or the second engagement recess 135 when the lock release button 155 is not pressed.

  The portable circular saw 101 according to the present embodiment is configured as described above. The operation and use method will be described below. As shown in FIGS. 1 and 2, the circular saw body 121 is normally placed at the top dead center position. At this time, the lock pin 137 in the lock mechanism 131 is engaged (inserted) into the first engagement recess 133 of the blade case 113 (see FIG. 2). Thereby, the circular saw main body 121 is locked at the top dead center position, and relative rotation around the rotation axis with respect to the base 111 is restricted. On the other hand, the lock claw 153 in the trigger lock mechanism 151 contacts and locks the upper surface portion 128b of the trigger 128 (see FIG. 7) to restrict the pulling operation of the trigger 128. As a result, the power switch 129 is locked in the off position.

When the workpiece is cut, the base 111 is placed on the workpiece and the lock release button 155 is pushed. The lock claw 153 moves to a position corresponding to the relief hole 128c of the trigger 128. (Refer to FIG. 8) and the pull operation of the trigger 128 is allowed. At the same time, the interlocking lever 159 is rotated around the shaft 159a, and the stopper pin 137 is pulled out from the first engaging recess 133, whereby the lock of the circular saw body 121 is released. Thereafter, the trigger 128 is pulled and the drive motor is energized through the power switch 129 to rotate the blade 123 and rotate the circular saw body 121 downward. By rotating the circular saw body 121 downward, as shown in FIG. 5, the lower edge 123a of the blade 123 protrudes downward from the base 111, and the lower edge 123a of the blade 123 Cutting work can be performed. As for the cutting depth, the base side lower stopper 165 is adjusted up and down to change the contact position with the circular saw body side stopper 163 to change the amount of protrusion of the lower edge 123a of the blade 123 from the lower surface of the base 111. Is arbitrarily set.
During the cutting operation, it is considered that the operator often holds the hand grip 127 by releasing the finger operated from the lock release button 155 while maintaining the pull operation of the trigger 128. In this case, the lock pin 137 moves in a direction approaching the side wall surface 113b of the blade case 113. However, since the lock claw 153 engages with the relief hole 128c of the trigger 128, the lock pin 137 comes into contact with the side wall surface 113b. It will stop at the position. Therefore, it does not become an obstacle to moving the circular saw body 121 up and down. (Assuming that the lock pin 137 is in contact with the side wall surface 113b, the second engaging recess 135 is in an obstructed state (closed state), so this case also does not become an obstacle).

  After the cutting operation, when the pulling operation of the trigger 128 is released and the circular saw body 121 is moved to the top dead center position, the lock pin 137 faces the first engagement recess 133 and, at the same time, its tip automatically The first engagement recess 133 is engaged (inserted). At this time, since the movable disk 141 is placed at the engagement prohibited position where the second engagement recess 135 is disturbed (closed) by the torsion spring 147, the lock pin 137 is engaged with the second engagement recess 135. The blade passes through the blade replacement position without matching (see FIGS. 10 and 12). As a result, the circular saw body 121 is locked at the top dead center position.

  Next, when exchanging the blade 123, the movable disk 141 is rotated to the engagement allowable position to bring the second engagement recess 135 into a receiving state (open state) (see FIG. 11). Thereafter, the lock release button 155 is pressed to release the lock of the circular saw body 121, and the circular saw body 121 is rotated downward from the top dead center position. When the circular saw body 121 is placed at the blade replacement position and the lock pin 137 faces the second engagement recess 135, the lock pin 137 is engaged with the second engagement recess 135 by the urging force of the compression coil spring 157. (See FIGS. 4 and 9). As a result, the circular saw body 121 is locked at the blade replacement position, and movement relative to the base 111 is restricted. At this blade replacement position, as shown in FIG. 3, the mounting flange 124 of the blade 123 faces the working hole 113a. For this reason, the mounting flange 124 is removed through the work hole 113a, and the blade 123 is replaced.

  As described above, the locking mechanism 131 of the circular saw body 121 according to the present embodiment is configured to lock the circular saw body 121 at both the top dead center position and the blade replacement position. Therefore, in addition to the lock mechanism for the top dead center position, it is possible to reduce the number of components of the lock mechanism 131 as compared to the conventional structure having a dedicated lock mechanism for the blade replacement position. Simplification of the structure and cost reduction can be realized rationally. Moreover, the lock mechanism 131 is engaged with or separated from the first engagement recess 133 set at the top dead center position and the second engagement recess 135 set at the blade replacement position, and the engagement grooves 133, 135. And a lock pin 137 to be operated. That is, since the lock mechanism 131 itself is composed of a small number of components, it is more effective in simplifying the structure and reducing the cost.

  Further, according to the present embodiment, the lock claw 153 for locking the trigger 128 is provided on the lock release button 155, and the lock release button 155 and the lock pin 137 for locking the circular saw body 121 are connected to the interlock lever 159. It is set as the structure linked via. Therefore, the lock of the circular saw main body 121 by the lock mechanism 131 and the lock of the trigger 128 by the trigger lock mechanism 151 can be simultaneously released by pressing one lock release button 155, and the lock release operation Becomes easier. Further, since the urging force for urging the lock pin 137 and the lock claw 153 in the lock direction is performed by the common compression coil spring 157, it is effective in reducing the number of parts. Further, by rotating the movable disk 141, the second engagement recess 135 can be easily switched between a receiving state in which the engagement of the lock pin 137 is allowed and an obstructing state in which the engagement is prohibited. .

  Note that the present invention is not limited to the above-described embodiments, and can be modified as appropriate. For example, in the present embodiment, the recess 135b provided on the outer peripheral edge of the movable disk 141 and the case-side recess 135a jointly form the second engagement recess 135, but the blade case 113 is locked. A second engagement recess 135 having a shape that can be engaged with the pin 137 is set, and the engagement of the lock pin 137 is allowed by opening and closing the second engagement recess 135 with a movable disk 141 provided as a lid member. Alternatively, the second engagement recess 135 having a shape that can be engaged with the lock pin 137 is set on the movable disc 141 itself, and the position of the second engagement recess 135 is rotated by rotating the movable disc 141. May be changed to a mode in which the engagement of the lock pin 137 is permitted or prohibited. Further, the movable disk 141 is not limited to the rotation operation, and may be changed to a linear operation.

  Further, the lock mechanism 131 in the present embodiment is configured such that the lock pin 137 as the lock member moves linearly and engages with the first engagement recess 133 or the second engagement recess 135. It may be configured by a lever-shaped member, and the lever-shaped member may be changed to a configuration in which the lever-shaped member rotates and engages with the first engagement recess 133 or the second engagement recess 135. Further, with respect to the lock mechanism 131, the lock pin 137 may be provided on the blade case 113 side, and the first engagement recess 133 and the second engagement recess 135 may be provided on the circular saw body 121 side. Further, the lock release means may be changed from the push button method to the lever method.

In view of the gist of the invention, the following aspects can be configured.
(Aspect 1)
“A portable circular saw according to claim 3,
The first and second engaging recesses are respectively formed on the side wall surfaces of the blade case, the lock member is a rod-shaped member, and the circular saw body moves between the initial position and the lower position. The first engaging recess or the second engaging member is moved along the side wall surface of the blade case integrally with the circular saw body and moved linearly in a direction intersecting the side wall surface. A portable circular saw inserted into the mating recess, thereby locking the circular saw body. "
According to the invention described in the aspect 1, the circular saw body can be rationally locked with a simple structure.

(Aspect 2)
“A portable circular saw according to claim 4,
The second engaging recess is constituted by a substantially semicircular recess formed in a side wall surface of the blade case and a substantially semicircular recess formed in an outer peripheral region of the movable member, When the movable member is rotated to the lock permissible position, the recess on the movable member side is opposed to the recess on the blade case side so that the lock member is allowed to be engaged, and the movable member is When rotated to the lock-prohibited position, an outer peripheral area where no depression on the movable member side is opposed to the depression on the blade case side is set to an obstructing state in which engagement of the lock member is prohibited. A portable circular saw characterized by "
According to the invention described in the aspect 2, the second engaging recess can be switched between the accepting state and the disturbing state with a simple structure.

(Aspect 3)
“A portable circular saw according to claim 3 or 4,
The first and second engaging recesses are respectively formed on the side wall surfaces of the blade case, the lock member is a rod-shaped member, and the circular saw body moves between the initial position and the lower position. The first engagement recess or the second engagement recess is moved along the side wall surface of the blade case integrally with the circular saw body and moved in a direction intersecting the side wall surface. It is configured to lock the circular saw body by this,
The second engaging recess is constituted by a substantially semicircular recess formed in a side wall surface of the blade case and a substantially semicircular recess formed in an outer peripheral region of the movable member, When the movable member is rotated to the lock permissible position, the recess on the movable member side is opposed to the recess on the blade case side so that the lock member is allowed to be engaged, and the movable member is When rotated to the lock-prohibited position, an outer peripheral area where no depression on the movable member side is opposed to the depression on the blade case side is set to an obstructing state in which engagement of the lock member is prohibited. A portable circular saw characterized by "
According to the invention described in Aspect 3, the effects described in Aspects 1 and 2 can be achieved.

It is a front perspective view which shows the whole structure of the portable circular saw which concerns on embodiment of this invention, and shows the state by which the circular saw main body was put in the top dead center position. It is a back surface perspective view which shows the whole structure of a portable circular saw, and shows the state by which the circular saw main body was put in the top dead center position. It is a front perspective view which shows the whole structure of a portable circular saw, and shows the state where the circular saw body is placed at the blade replacement position. It is a back surface perspective view which shows the whole structure of a portable circular saw, and shows the state by which the circular saw main body was placed in the blade replacement position. It is a front perspective view which shows the whole structure of a portable circular saw, and shows the state where the circular saw body is placed at the cutting work position. It is a back surface perspective view which shows the whole structure of a portable circular saw, and shows the state by which the circular saw main body was put in the cutting operation position. It is a front perspective view which shows the whole structure of a circular saw main-body part, and shows the state (locked state) where the lock release button is not pushed. It is a front perspective view which shows the whole structure of a circular saw main-body part, and shows the state (lock release state) by which the lock release button was pushed. It is a back surface perspective view which shows the state by which the circular saw main-body part was locked to the braid | blade exchange position. It is a back surface perspective view which shows the state by which a circular saw main-body part is not locked to a braid | blade exchange position. It is explanatory drawing which shows the switching operation | movement of a movable disk in a braid | blade replacement | exchange position, and is a figure which shows the state in which the 2nd engagement recessed part was put in the acceptance state. It is explanatory drawing which shows the switching operation | movement of a movable disk in a braid | blade exchange position, and is a figure which shows the state by which the 2nd engagement recessed part was put in the obstruction | occlusion state. It is a disassembled perspective view which shows the attachment structure of a movable disc. It is explanatory drawing which shows the connection structure of a lock release button and an interlocking lever.

Explanation of symbols

101 portable circular saw 111 base 113 blade case 113a working hole 113b side wall surface 113c receiving recess 121 circular saw body 122 rotating cylinder (rotating shaft)
123 Blade 123a Lower edge portion 124 Mounting flange 125 Motor housing 125a Pin receiving portion 127 Hand grip 128 Trigger 128a Shaft 128b Upper surface portion 128c Relief hole 129 Power switch 131 Lock mechanism (main body side lock mechanism)
133 1st engagement recessed part (1st engagement recessed part)
135 2nd engagement recessed part (2nd engagement recessed part)
135a Case side depression 135b Movable disk side depression 137 Lock pin (lock member)
141 Movable disc (movable member)
143 Mounting screw 145 Washer 147 Torsion spring 151 Trigger lock mechanism (power switch lock mechanism)
153 Lock claw 155 Unlock button 155a Shaft 155b Head 157 Compression coil spring 159 Interlocking lever 159a Shaft 159b Notch 161 Base side upper stopper 163 Circular saw body side stopper 165 Base side lower stopper 165a Screw part 167 Compression coil spring

Claims (4)

A base having a blade case;
A rotating saw blade that performs a processing operation on a workpiece, and a circular saw body that is connected to the base so as to be relatively movable; and
The circular saw body has an initial position where the lower edge of the rotary saw blade is moved above the base and the entire rotary saw blade is housed in the blade case, and the rotary saw body rotates from the initial position. A portable circular saw that can be machined by the rotary saw blade by moving the lower edge of the saw blade to a lower position protruding below the base,
When the circular saw body is placed at the initial position and at an intermediate position set between the initial position and the lower position, the circular saw body is locked and relative to the base. A body lock mechanism that restricts movement;
Unlocking means operable to unlock the circular saw body by the body locking mechanism,
The main body locking mechanism has a movable member that is operated to switch between a lock permissible position that allows the circular saw body to be locked by the main body locking mechanism and a lock prohibition position that prohibits the locking at the intermediate position. In a state where the movable member is placed at the lock allowable position, the circular saw body is locked at the intermediate position to restrict relative movement with respect to the base, and the movable member is placed at the lock prohibited position. In the state, the circular saw body is configured to allow the circular saw body to move between the initial position and the lower position without being locked at the intermediate position. The portable circular saw according to claim 1, wherein
A motor for driving the rotary saw blade, a power switch for turning on / off the power of the motor, and the power source when the circular saw body is placed at the initial position and at the intermediate position. A power switch lock mechanism that locks the switch in an off position for turning off the motor,
The power switch locking mechanism is configured such that when the circular saw body is unlocked by the main body locking mechanism by the operation of the unlocking means, the power switch is unlocked simultaneously by the unlocking means. A portable circular saw characterized by. The portable circular saw according to claim 1 or 2,
The main body locking mechanism is provided on the base side, provided on the circular saw main body side, a first engagement concave portion corresponding to the initial position and a second engagement concave portion corresponding to the intermediate position, The first engaging recess or the second engaging recess can be moved in a direction approaching or separating from the first engaging recess or the second engaging recess, and a biasing force is applied in a direction approaching the first engaging recess or the second engaging recess. A locking member,
When the circular saw body is placed at the initial position, the lock member moves in a direction approaching the first engagement recess by the biasing force and engages with the first engagement recess. Thus, the circular saw body is locked at the initial position, and when the circular saw body is placed at the intermediate position, the movable member is placed at the lock permissible position via the biasing force. It moves in the direction approaching the second engagement recess and engages with the second engagement recess, thereby locking the circular saw body in the intermediate position and placing the movable member in the lock prohibition position. The portable circular saw is configured to pass through the intermediate position without being engaged with the second engagement concave portion in a state where the second circular engagement saw is engaged. A portable circular saw according to claim 3,
The movable member is rotatable between the lock allowable position and the lock prohibition position. When the movable member is rotated to the lock allowable position, the second engagement recess is the second engagement recess. The second engaging recess engages the locking member with the second engaging recess when the locking member is placed in a state of receiving the engagement of the locking member with respect to A portable circular saw characterized in that it is placed in an obstructing state.

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