JP4761257B2 - Fastener driving machine - Google Patents

Description

  The present invention relates to a fastener driving machine for driving fasteners such as nails, scissors, and staples into a workpiece, and more particularly, to a fastener driving machine having a mechanism for preventing an empty shot of a fastener.

  Generally, a piston that reciprocates in a cylinder is used as a drive mechanism for a pneumatic or combustion type driving machine body that gives reciprocating motion to a driver blade for driving fasteners such as nails, scissors, and staples. The end portion is provided with an impact relief bumper for absorbing surplus energy of the driver blade after driving the fastener. Similarly, in the electric driving machine body that converts the rotational driving force of the flywheel driven by the electric motor into a linear driving force and transmits it to the driver blade, an impact mitigation bumper is provided at the end of the driver's reciprocating path. Provided.

  In these fastener driving machines, a magazine loaded with a large number of connecting fasteners is engaged with a nose portion attached to the main body of the driving machine, and the fasteners are sequentially supplied to the nose portion by reciprocating the driver blade. It is something to be typed in. Also, the driving mechanism of the driving machine main body that gives the driving reciprocating motion is an operation of a mechanical link mechanism based on an interlocking operation of a push lever pressing operation and a trigger lever pulling operation or an AND gate electric circuit based on both lever operations. The driving mechanism of the driver blade is activated by the operation. Therefore, if the driver blade is driven and blown by pressing the push lever or the like when no fastener is loaded in the nose portion, the impact mitigating bumper or the like disposed in the cylinder or the like is excessive. There is a problem in that the durability of the driving machine main body is remarkably lowered due to an excessive impact, or the driving machine main body or the nose portion is damaged.

  In order to solve this problem, for example, as disclosed in Patent Document 1 below, a fastener driving machine provided with an idle driving prevention mechanism is well known. This type of idling prevention mechanism is a feeder mechanism provided in the feeder when the remaining amount of fasteners loaded in a connected manner in the magazine becomes less than a predetermined amount and the feeder in the magazine advances to a predetermined position. The lock arm that is moved by being pushed by the joint prohibits the movement of the push lever and stops the drive mechanism of the driver blade.

JP-A-8-141933

  However, the inventor of the present application has found the following problems at the stage of studying the conventional mechanism for preventing idle driving of a fastener driving machine.

  That is, a feeder engaging portion provided in the feeder when the remaining amount of the connecting fastener loaded in the magazine becomes a predetermined amount (set remaining amount) and the feeder moves forward to a predetermined position in the magazine during normal operation. Presses one end of the lock arm, and the other end of the lock arm engages with the engaging portion of the push lever, thereby prohibiting the push lever from moving. As a result, the driving operation of the driver blade is not activated. That is, when the remaining amount of the coupling fastener (for example, nail) loaded in the magazine is reduced to a predetermined amount (for example, four nails), the other end of the lock arm is engaged as a stopper against the movement of the push lever. Therefore, the pushing operation of the push lever becomes impossible, and the driving operation of the driver blade is not started.

  However, although it is not generally implemented as a driving machine operation method, the driver blade is continuously driven by pulling only the trigger lever while the push lever is inadvertently pressed against the workpiece. When the so-called push lever dragging operation is performed, the remaining amount fastener of a predetermined amount or less is not pressed to the correct position of the nose injection hole by the feeder. For this reason, since the remaining amount fastener of the predetermined amount or less exists in an unstable position in the space between the feeder and the nose injection hole in the magazine, if the driver blade is hit against the nose injection hole in this state, A problem arises in that the nose portion is clogged with a fastener such as a nail or the fastener damages the nose portion.

  Further, the engagement between the other end of the lock arm and the push lever immediately after the remaining amount fastener in the magazine is reduced to the predetermined amount (set amount) is performed in a thin or weak state. When the push lever is pressed against the next workpiece in this state, the weak engagement between the lock arm and the push lever may be released due to an impact or the like generated when the push lever is pressed against the workpiece. When the trigger lever is pulled in this state and the driver blade is hit against the nose injection hole, the nose portion is clogged with a fastener such as a nail, or the fastener damages the nose portion, similar to the push lever dragging operation. Occurs.

  Accordingly, an object of the present invention is to provide a fastener driving machine that avoids the problem that a remaining amount of fasteners equal to or less than a predetermined amount in a magazine is clogged or damaged in the nose portion in the fastener blanking prevention mechanism. It is to provide.

  Another object of the present invention is to provide a fastener driving machine that improves the reliability and durability of the idle driving prevention mechanism.

  In order to achieve the above object, the outline of typical ones of the inventions disclosed in the present application will be described as follows.

  According to one aspect of the present invention, there is provided a driver blade for driving a fastener, a driving machine body having a driving mechanism for giving a reciprocating motion to the driver blade, guiding the reciprocating motion of the driver blade, and A magazine portion having a nose portion having a nose injection hole to which a fastener is supplied, and one end portion engaged with the nose portion and extending in a direction crossing the extending direction of the nose injection hole. A plurality of connected fasteners loaded into the magazine portion are pressed into the nose injection hole from the other end side, and the remaining amount fastener after the fastener is driven into the nose injection hole is A magazine portion containing a feeder that advances to the nose injection hole, a forward position that is urged and projected from the tip of the nose injection hole, and a rear position that retreats near the tip of the nose injection hole when pressed. In between, A push lever provided to be movable in a direction parallel to the extending direction of the nose injection hole, and activation of the drive mechanism of the driving machine main body by an operation cooperating with a pressing operation of the push lever to the rear position. A locking lever that extends from one end portion to the other end portion, and an intermediate portion between the both end portions is held by the nose portion or the magazine portion. And when the remaining amount of fasteners loaded in the magazine portion decreases below a predetermined amount, it engages with the one end of the lock arm and presses the one end of the lock arm toward the nose injection hole A shape of the push lever is formed to engage with the other end portion of the lock arm when the feeder engaging portion formed on the feeder and the one end portion of the lock arm are pressed. And an intermediate portion of the lock arm held by the nose portion or the magazine portion is provided in the nose portion or the magazine portion. The support shaft is supported so as to be rotatable, and is supported to be movable away from the support shaft in the direction of the nose injection hole.

  According to another aspect of the present invention, the intermediate portion of the lock arm is formed with a turning hole or turning notch that is larger than the diameter of the support shaft, and the turning hole or turning notch. A part of the inner peripheral surface of the portion is rotatably supported by the support shaft, and the support portion of the inner peripheral surface is separated from the support shaft in the rotation hole portion or the rotation notch portion. It is supported so as to be movable in the direction of the nose injection hole.

  According to still another aspect of the present invention, the remaining amount of the fastener loaded in the magazine portion at the front position of the push lever is reduced to the predetermined amount, and the feeder engaging portion is moved to the lock arm. When the one end portion is pressed, the lock arm is rotated with the support shaft as a fulcrum to engage the other end portion of the lock arm with the push lever engagement portion, and the forward position of the push lever. To the rear position, the remaining amount of the fastener loaded in the magazine portion at the rear position of the push lever is reduced below the predetermined amount, and the feeder engaging portion is When the one end side is pressed, the push lever engaging portion acts as a support portion for supporting the other end portion of the lock arm, thereby The intermediate portion of the hook arm is moved away from the support shaft in the direction of the nose injection hole so that the feeding portion of the feeder can press the fastener even when the remaining amount of the fastener is equal to or less than the predetermined amount. Constitute.

  According to the idling prevention mechanism of the present invention, the intermediate portion of the lock arm held in the nose portion or the magazine portion is supported rotatably with respect to the support shaft provided in the nose portion or the magazine portion. Since it is supported so as to move away from the support shaft in the direction of the nose injection hole, when the push lever engagement portion is operated as a support portion for supporting the other end portion of the lock arm, one end portion of the lock arm is locked. The intermediate part of the arm can be moved away from the support shaft in the direction of the nose injection hole. Thereby, even if the remaining amount of the fastener in the magazine becomes a predetermined amount or less, the feeder of the feeder can press the fastener. For this reason, the remaining amount fastener of a predetermined amount or less is always pressed to the correct position in the nose injection hole without being in an unstable position in the space between the feeder in the magazine and the nose injection hole. Therefore, if the driver blade is hit against the nose injection hole in this state, the problem that the nose portion is clogged with a fastener such as a nail or the fastener damages the nose portion can be avoided. Therefore, the reliability and durability of the idle driving prevention mechanism can be improved.

  The above and other objects, and the above and other features of the present invention will become more apparent from the following description of the present specification and the accompanying drawings.

  Embodiments in which the present invention is applied to a compressed air type nail driver will be described below with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiments, and the repetitive description thereof will be omitted. Further, in the following description relating to the nail driving machine of the present invention, the direction in which the fastener is driven in the state where the fastener such as a nail is driven in the horizontal direction by the nail driving machine is referred to as “ Although "left direction or right direction" is expressed, it is not limited to a specific embodiment or intention. In a state in which the direction in which the fastener is driven is installed in the vertical direction, it can be described as “lower or lower” and the opposite direction as “upper or upper”, which both limit the gist of the present invention. Not what you want.

  FIG. 1 is an overall front view (including a partial cross section) of a nail driving machine according to an embodiment of the present invention, and FIG. 2 is an overall rear view (outer appearance) of the nail driving machine according to the embodiment shown in FIG. 1), the direction in which the fastener is driven is shown as the direction from the left hand side to the right hand side (right direction) as opposed to the direction from the right hand side to the left hand side (left direction) in FIG. .

[Overall configuration of nailing machine]
The nail driving machine 1 includes a nail driving machine body 2 and a nose assembly part 4 including a nose part 3 and a magazine part 5. The nail driver main body 2 forms a part that surrounds the drive mechanism of the driver blade 11 such as the cylinder 6 and the piston 7, and a part of the handle portion 8 and the pressure accumulating chamber 14 for gripping the nail driver 1. It is surrounded by a housing 9 consisting of parts.

  An air plug 10 is provided at one end portion (lower end portion) of the handle portion 8 and a dust cap 12 for preventing dust intrusion is covered. However, when operating the nail driver main body 2, the dust cap 12 is removed. Then, an air hose from a compressor (not shown) is connected to the air plug 10 to supply compressed air. Further, the nose portion 3 of the nose assembly portion 4 is disposed at one end portion of the main body 2, and one end of the magazine portion 5 of the nose assembly portion 4 is fastened to the handle portion 8 of the nail driving machine main body 2 with bolts (bolts and bolts). Nut) 13.

  Compressed air serving as a driving source for the piston 7 is stored in the pressure accumulating chamber 14 in the nail driver main body 2 through the air plug 10. A cylinder 6 is provided in the nail driver main body 2, and a piston 7 capable of reciprocating in the left-right direction is provided in the cylinder 6. The piston 7 has a driver blade 11 attached integrally to the left surface (the nose portion 3 side). The head of the connecting nail (fastener) 15 loaded in the nose portion 3 from the magazine portion 5 is sequentially hit by the tip portion of the driver blade 11.

  As shown in FIG. 1, a nose injection hole that guides the driver blade 11 when the driver blade 11 moves to the left in the axial direction (bottom dead center side) together with the piston 7. 3a is disposed, and a nail 15 is driven out from a nose injection hole 3a to a workpiece (not shown) such as wood. A known O-ring 7 a made of a flexible material such as rubber is provided on the outer periphery of the piston 7 in order to seal the piston 7.

  A head valve (main valve) 16 made of a flexible material is housed in the right side (top dead center side) of the cylinder 6 so as to be slidable in the left-right direction (up-down direction) on the inner wall surface of the partition part 9a. Yes. The head valve 16 is urged to the left dead center side (bottom dead center side) by the pressing force of the head valve spring 16a and the pressing force of compressed air flowing into the head valve control passage (not shown) communicating with the trigger valve 17. Has been.

  The operation section operated by the operator includes a trigger lever 18, an arm plate 19 rotatably attached to the trigger lever 18, an arm protruding from the tip of the nose injection hole 3 a and engaging with the arm plate 19. A push lever 20 extending to the vicinity of the plate 19 is provided, and the trigger lever 18 can be operated by linking to the pressing operation of the push lever 20. That is, the opening and closing of the trigger valve portion 17 is controlled by the operation of the trigger lever 18 that cooperates with the pressing operation of the push lever 20 to the rear position, and the reciprocating motion of the piston 7 is activated.

  As shown in FIG. 2, the push lever 20 has a front end portion 20 a that protrudes from the front end of the nose portion 3 (nose injection hole 3 a), and a rear end portion 20 b that engages with the arm plate 19. It extends from the back side of the nose portion 3 in parallel with the extending direction of the nose injection hole 3a from 20a to the rear end portion 20b. An adjuster portion 21 is attached to the push lever 20 to adjust the entire length of the push lever 20, and the entire push lever 20 is attached to the nose portion 3 by a biasing spring (not shown) provided in the adjuster portion 21. It is urged to the front position from the front end. When the tip 20a of the push lever 20 is pressed against the workpiece in a normal state, the tip 20a moves backward to a rear position in the vicinity of the tip of the nose portion 3 (nose injection hole 3a). As shown in FIG. 1, the movement of the tip 20 a moves the entire push lever 20 toward the trigger lever 18, the push lever rear end 20 b engages with the arm plate 19, and the trigger lever 18 performs a starting operation. Is possible.

  In FIG. 1, a control passage (not shown) for pressing the head valve 16 is connected to the trigger valve portion 17, and the nail driver main body 2 according to the left and right opening / closing (up / down opening / closing) of the plunger 17 a of the trigger valve portion 17. Communicates with the compressed air accumulated in the external atmosphere or the pressure accumulating chamber 14. More specifically, the plunger 17a cooperates with the valve piston provided in the trigger valve portion 17 and communicates the head valve control passage to the atmosphere in accordance with the left-right movement (vertical movement) of the plunger 17a. Or it is made to communicate with the pressure accumulation chamber 14 filled with compressed air. That is, as shown in FIG. 1, when the plunger 17 a is in the left side state (downward state), in other words, when it is biased to the left side (downward position) by the coil spring in the trigger valve portion 17. The head valve control passage communicates with the pressure accumulation chamber 14 and is supplied with compressed air. On the contrary, when the plunger 17a is pulled rightward (upward) by the arm plate 19 and the trigger lever 18, the control passage for pressing the head valve 16 is connected with the external air in the vicinity thereof via the trigger valve portion 17. Communicate. Specifically, in the nailing operation, the push lever 20 is pressed by the workpiece, the push lever 20 is moved backward, and the arm plate 19 is pushed up. When pulled in the direction of the trigger valve 17 (upward), as described above, the plunger 17a is pushed leftward (upward), and the head valve control passage communicates with the atmosphere through the trigger valve portion 17. As a result, the head valve 16 moves to the top dead center side in the X direction, the piston upper chamber 27 partitioned by the piston 7 and the head valve 16 is communicated with the pressure accumulating chamber 14, and compressed air is supplied from the pressure accumulating chamber 14 to the piston 7. The piston 7 is supplied to the piston upper chamber 27, and the piston 7 is moved in the left direction (downward direction) to give a striking force to the driver blade 11 integrally attached to the piston 7.

  The left end (lower end) of the cylinder 6 is provided with an impact reducing bumper 25 for absorbing surplus energy of the piston 7 after the nail 15 is driven. A part of the bumper 25 is larger in diameter than the inner diameter of the cylinder 6 so that the shock relaxation bumper 25 does not move to the top dead center side of the cylinder 6.

  A return air chamber 22 for returning the piston 7 from the bottom dead center to the top dead center is provided on the outer periphery of the left end (lower end) of the cylinder 6, and the direction of the return air chamber 22 from the cylinder 6 during the reciprocating stroke of the piston 7 is provided. An air passage 23 having a check valve 23 a that communicates only with the cylinder is provided, and an air passage 24 that communicates the cylinder 6 with the return air chamber 22 is provided on the outer periphery of the lower end of the cylinder 6. The air duster 26 has a button 26a, and is a device that blows out dust such as wood chips generated during work by injecting compressed air from the outlet.

[Structure of anti-blank mechanism]
Next, the structure of the idle driving prevention mechanism according to the present invention will be described with reference to the front view of FIG. 1 and the side view of FIG. 3 (side view from the direction AA of FIG. 1).

  The magazine portion 5 has one end portion 5a engaged with the nose portion 3 and the other end portion 5b extending in a direction intersecting with the extending direction of the nose injection hole 3a. A plurality of connection-type nails (connection fasteners) 15 to be loaded into the magazine portion 5 are pressed into the nose injection hole 3a from the other end portion 5b side, and after the fastener is driven into the nose injection hole 3a. A feeder 51 for advancing the remaining amount fastener 15 to the nose injection hole 3a is mounted. The feeder 51 is urged in the direction of the one end portion 5a of the magazine portion 5 by a spring spring (not shown), and always presses the connecting fastener 15 in the direction of the nose injection hole 3a by the feeding portion 51a. Thus, when the loaded connecting fasteners 15 are sequentially driven and consumed, the remaining amount fastener 15 is advanced in the direction toward the nose injection hole 3a, so that the remaining amount fastener is always in the nose injection hole 3a. Press 15 to load. The feeder 51 has a feeder engaging portion 51b. When the remaining amount fastener 15 becomes a predetermined amount (for example, four nails) or less, the feeder 51 is pressed in a direction toward the nose injection hole 3a.

  As shown in FIG. 3, the lock arm 52 extends from one end portion 52 a to the other end portion 52 b, and an intermediate portion 52 c between the both end portions is held by the nose portion 3 or the magazine portion 5. For this holding, the support shaft 53, the holding portion 4a provided in the nose portion 3 or the magazine portion 5, and the one end portion 52a of the lock arm 52 are urged toward the other end portion 5b of the magazine 5 (downward). A spring 52d is used. The lock arm 52 is supported so that an intermediate portion 52c of the lock arm 52 can rotate with respect to a support shaft 53 provided in the nose portion 3 or the magazine portion 5, and as shown in FIG. Is movably supported in the direction of the nose injection hole so as to be separated by a distance d1. In particular, in order to enable the lock arm 52 to move away from the support shaft 53, the intermediate portion 5c of the lock arm 52 is provided with a turning notch 52f as shown in FIG. A rotation hole 52f as shown in (b) of FIG. These have an oval inner circumferential shape at least on the side of the nose injection hole so that the one end 52a of the lock arm 52 can move in the direction of the nose injection hole about the other end 52b. As a result, as shown in FIG. 12, the intermediate portion 52c of the lock arm 52 moves away from the first position P1 when supported by the support shaft 53 with a distance d1 to the second position P2. It becomes possible.

  A push lever engaging portion 20 c is formed on the push lever 20 in association with the lock arm 52. As shown in FIG. 7 described later, the push lever engaging portion 20c includes a case where the flat surface portion of the lock arm 52 is engaged with the side surface portion thereof, and a case where the lock arm is engaged with the flat surface portion as shown in FIG. 12 described later. 52 may be engaged with the lower side surface portion.

[Operation of the mechanism for preventing blank shots]
Next, the operation of the idle driving prevention mechanism will be described with reference to FIGS. 8 to 12 which are side views from the AA direction shown in FIG.

1. When the nail is not loaded As shown in FIG. 8, when the nail is not loaded in the magazine portion 5, the feeder engaging portion 51b urged by the spring (not shown) approaches the nose injection hole 3a. One end 52a of the lock arm 52 is pressed in the direction, and the other end 52b of the lock arm 52 is rotated in the S direction far from the nose injection hole 3a with the support shaft 53 as a fulcrum. As a result, the push lever engaging portion 20 c completely overlaps with the other end portion 52 b of the lock arm 52, and rotates so as to be completely engaged with the other end portion 52 b of the lock arm 52. Even if the push lever 20 is pressed toward the trigger lever in this state, that is, even if the push lever 20 is pressed against a workpiece (not shown), the other end 52b of the lock arm 52 exists in the path of the push lever 20. Therefore, the movement of the push lever 20 in the rear position direction is prevented. Therefore, the other end portion 20b of the push lever 20 cannot be engaged with the arm plate 19, so that the trigger valve portion 17 cannot be activated. That is, the nail driving operation by the driver blade 11 is stopped.

  When the state shown in FIG. 8 is reached, if the feeder 51 (see FIG. 1) is retracted and the fasteners (nails) are replenished in the magazine part 5, the feeder engaging part as shown in FIG. Since 51b releases the pressure to the lock arm one end 52a, the other end 52b of the lock arm is retracted from the movement path of the push lever 20 and returns to the state shown in FIG. 3 so that the work can be resumed.

2. As shown in FIG. 9, when the nail is loaded in the magazine unit 5 and the remaining amount is larger than the set remaining amount (for example, five), the feeder engaging portion 51b is Although the lock arm one end portion 52a is pressed, the lock arm other end portion 52b with the support shaft 53 as a fulcrum does not rotate to the track of the push lever engaging portion 20c. For this reason, the push lever engaging portion 20c does not engage with the lock arm other end portion 52b. If the push lever 20 is pressed toward the trigger lever in this state, the other end 52b of the lock arm 52 moves toward the rear position of the push lever 20 as shown in the rear view of FIG. Since 20b engages with the lock arm 19, the trigger valve part 17 can be started. That is, a nail driving operation by the driver blade 11 is performed.

3. The state where the remaining amount of nail is a set amount As shown in the rear view of FIG. 10 and FIG. 7, the nail remaining amount loaded in the magazine portion 5 is energized in a state where the amount is reduced to a set amount (for example, 4). The feeder engaging portion 51b presses the lock arm one end portion 52a in the N direction approaching the nose injection hole 3a, and the lock arm other end portion 52b is turned away from the nose injection hole 3a in the S direction with the support shaft 53 as a fulcrum. As a result, the push lever engaging portion 20c is overlapped with the other end portion 52b of the lock arm 52 and rotated to engage with the other end portion 52b of the lock arm. As shown in the rear view of FIG. 7, even if the push lever 20 is pressed in the trigger lever direction in this state, the lock arm other end 52b prevents the push lever 20 from moving in the rear position direction. Accordingly, the push lever other end portion 20b cannot be engaged with the trigger lever 18, so that the trigger valve portion 17 cannot be activated, and the nail driving operation by the driver blade 11 is stopped.

  In this state, since the nail remaining amount is a set amount (for example, four), the push lever engaging portion 20c is engaged with the other end portion 52b of the lock arm 52 thinly or weakly. When the push lever 20 is pressed against the workpiece or the like without being conscious of the setting amount, the engagement of the other end 52b of the lock arm may be released due to an impact at the time of pressing. When the trigger valve 18 is activated by pulling the trigger lever 18 in the released state, the nail driving operation by the driver blade 11 becomes possible.

  However, in this case, the problem with the conventional nail driver is that when the push lever 20 is pressed against a workpiece or the like in a state where the engagement of the lock arm other end 52b is released, the push lever engaging portion The plane portion 20c acts as an engaging portion (fulcrum) with respect to the lock arm other end portion 52b, and disables the rotation of the lock arm one end portion 52a in the N direction. In other words, in the conventional nail driving machine, it is impossible to press the remaining amount nail below the set amount (four or less) in the direction of the nose injection hole 3a (N direction) by the feeder feeding portion 51a. For this reason, the remaining amount nail 15 below the set amount is not pressed to the correct position of the nose injection hole 3a by the feeder 51, so that the space between the feeder feed part 51a and the nose injection hole 3a in the magazine part 5 is not filled. It will be in a stable position. When the driver blade 11 is hit against the nose injection hole 3a in such a state where the setting of the nail is unstable, there is a problem that the nose injection hole 3a or the like is clogged with a fastener such as a nail or the fastener damages the nose portion 3. Occurs. According to the present invention, such a problem is avoided for the following reason.

4). FIG. 11 shows a case where the driving operation is continuously performed by pulling the trigger lever 18 while maintaining the state where the push lever 20 is pressed, that is, while maintaining the state where the push lever 20 is pressed against the workpiece. An engaged state in which the remaining amount nail 15 has reached a set amount (four) is shown. In other words, in the case where drag driving is performed while the push lever 20 is pressed against the workpiece, the remaining nail 15 is reduced to the set amount (four). In this state, the pressed flat portion of the push lever engaging portion 20c acts as an engaging portion (fulcrum) for the lock arm other end portion 52b. In this case, since the inner peripheral portion of the rotation hole 52f is formed in an oval shape, the movement of the lock arm intermediate portion 52c in the N direction is not restricted by the support shaft 53.

  FIG. 12 shows an engaged state in which the remaining nail 15 is less than or equal to the set amount (4 to 0), particularly when the drag driving operation is performed as in the case shown in FIG. As described above, the flat portion of the pressed push lever engaging portion 20c acts as an engaging portion (fulcrum) with respect to the lock arm other end portion 52b, and the lock arm intermediate portion 52c is an oval turning hole. Since it can hold | maintain so that it can move to N direction, without being restrained by the spindle 53 by 52f, the feeder feeding part 51a can always press the residual amount nail 15 to the nose injection hole 3a direction (N direction). In other words, since the fulcrum of the lock arm 52 moves from the support shaft 53 to the push lever engaging portion 20c, the rotation center of the lock arm 52 can be moved from the intermediate portion 52c to the other end portion 52b. The one end 52a can be further moved in the N direction from the initial setting position of the feeder engaging portion 51b.

  Therefore, even if the remaining amount of nail 15 is reduced below the set amount (four), the remaining amount nail 15 can always be pressed in the direction of the nose injection hole 3a (N direction) by the feeder feeding portion 51a, and the remaining amount of nail is always nose. Since it is set correctly in the injection hole 3a, even if the driver blade 11 is hit against the nose injection hole 3a in a state where the remaining amount of nail 15 is reduced below the set amount (four), a nail or the like is applied to the nose injection hole 3a. It is possible to prevent clogging of the fasteners or damage of the nose portion 3 due to the fasteners.

  Further, the engagement between the lock arm other end portion 52b and the push lever engaging portion 20c immediately after the remaining amount fastener 15 in the magazine portion 5 is reduced to the set amount is performed in a thin or weak state. When the push lever is pressed against the next workpiece in this state, the weak engagement between the lock arm other end 52b and the push lever engaging portion 20c is released due to an impact or the like generated when the push lever is pressed against the workpiece. Even if there is a time, even if the remaining amount of nail 15 is reduced below the set amount (four) as in the case of dragging of the push lever, as described above, the remaining amount of nail 15 is always kept by the feeder feeding portion 51a. Since it can be pressed in the direction of the nose injection hole 3a (N direction), it is possible to prevent the nose injection hole 3a or the like from being clogged with a fastener such as a nail or damage to the nose portion 3 due to the fastener. Accordingly, it is possible to improve the reliability and durability of the nail driving machine having the blank driving prevention mechanism.

  In the above embodiment, the case of a nail was described as the fastener of the driving machine. However, the present invention is a fastener driving device for driving a fastener other than a nail such as a staple (a U-shaped nail) or a screw. It can also be applied to machines. In addition to the compressed air type, the present invention can achieve the same effects as the compressed air type driving machine described above even when applied to a combustion type or electric type driving machine.

  Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention. It is.

1 is an overall front view of a fastener driving machine according to an embodiment of the present invention. The whole rear view of the fastener driving machine shown in FIG. The principal part side view from the AA direction of the fastener driving machine shown in FIG. 1 (in the case of an initial state). The front view of the lock arm member used for the fastener driving machine shown in FIG. The whole rear view in the normal driving state of the fastener driving machine shown in FIG. The whole rear view before the push lever press of the fastener driving machine shown in FIG. The whole rear view after the push lever press of the fastener driving machine shown in FIG. The principal part side view from the AA direction of the fastener driving machine shown in FIG. 1 (in the case of zero nail remaining amount). The principal part side view from the AA direction of the fastener driving machine shown in FIG. 1 (in the case of five nail remaining amount). The principal part side view from the AA direction of the fastener driving machine shown in FIG. 1 (in the case of four nail remaining amount). The principal part side view from the AA direction of the fastener driving | running | working machine shown in FIG. The principal part side view from the AA direction of the fastener driving machine shown in FIG. 1 (in the case of drag driving of 4 to 0 nail remaining amount).

Explanation of symbols

1: Nail driving machine 2: Nail driving machine body 3: Nose part 4: Nose assembly part 4a: Lock arm holding part 5: Magazine part 6: Cylinder 7: Piston 7a: O-ring 8: Handle part 9: Housing part 9a: Partition part 10: Air plug 11: Driver blade 12: Dust cap 13: Fastener (bolt / nut) 14: Pressure accumulating chamber 15: Connecting nail 16: Head valve 16a: Head valve spring 17: Trigger valve part 17a: Plunger 18: Trigger lever 19: Arm plate 20: Push lever 20a: Push lever one end 20b: Push lever other end 20c: Push lever engaging part 21: Adjuster 22: Return air chamber 23: Air passage 23a: Check valve 24 : Air passage 25: Bumper for shock reduction 26: Air duster 27: Upper piston chamber 51: Feeder 51a: Feeder feeding portion 51b: Feeder engaging portion 52: Lock arm 52a: Lock arm one end portion 52b: Lock arm other end portion 52c: Lock arm intermediate portion 52d: Spring engaging portion 52e: Biasing spring 52f: For rotation Cut or turn hole 53: spindle

Claims (3)

A driving machine main body having a driver blade for driving the fastener and a drive mechanism for reciprocating the driver blade;
A nose portion for guiding the reciprocating motion of the driver blade and having a nose injection hole to which a fastener is supplied;
A magazine portion having one end portion engaged with the nose portion and having the other end portion extending in a direction intersecting with the extending direction of the nose injection hole, and a plurality of coupling type fasteners loaded in the magazine portion A magazine part containing a feeder that presses a tool into the nose injection hole from the other end side and advances a remaining amount fastener after driving the fastener in the nose injection hole to the nose injection hole;
A push lever movably provided between a forward position urged and projected from the tip of the nose injection hole, and a rear position retracted to the vicinity of the tip of the nose injection hole when pressed;
In a fastener driving machine comprising: a trigger lever that controls activation of the drive mechanism of the driving machine main body by an operation that cooperates with a pressing operation of the push lever to the rear position;
A lock arm extending from one end to the other end, and an intermediate portion between the both ends being held by the nose portion or the magazine portion;
When the remaining amount of the fastener loaded in the magazine portion decreases below a predetermined amount, it engages with the one end portion of the lock arm and presses the one end portion of the lock arm toward the nose injection hole. A feeder engaging portion formed on the feeder;
A blanking prevention mechanism comprising: a push lever engaging portion formed on the push lever so as to engage with the other end of the lock arm when the one end of the lock arm is pressed; Have
The intermediate portion of the lock arm held by the nose portion or the magazine portion is rotatably supported and separated from the support shaft provided in the nose portion or the magazine portion. The fastener driving machine is supported so as to be movable in the direction of the nose injection hole. The intermediate portion of the lock arm is formed with a turning hole or turning notch that is larger than the diameter of the support shaft, and a part of the inner peripheral surface of the turning hole or turning notch is the It is supported rotatably by a support shaft, and the support portion on the inner peripheral surface is supported away from the support shaft and movable in the direction of the nose injection hole in the rotation hole portion or the rotation notch portion. The fastener driving machine according to claim 1, wherein: When the remaining amount of the fastener loaded in the magazine portion at the front position of the push lever is reduced to the predetermined amount and the feeder engaging portion presses the one end portion of the lock arm, the support shaft is By rotating the lock arm as a fulcrum, the other end of the lock arm is engaged with the push lever engaging portion, and the movement of the push lever from the front position to the rear position is stopped.
When the remaining amount of the fastener loaded in the magazine portion at the rear position of the push lever decreases below the predetermined amount and the feeder engaging portion presses the one end side of the lock arm, the push By causing the lever engaging portion to act as a support portion for supporting the other end portion of the lock arm, the intermediate portion of the lock arm is moved away from the support shaft in the direction of the nose injection hole, and the fastener 2. The fastener driving machine according to claim 1, wherein the feeder driving unit can press the fastener even when the remaining amount of the feeder becomes equal to or less than the predetermined amount.

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