JPH0890449A - Operation switching device for air nailing machine - Google Patents

Abstract

PURPOSE: To provide an air nailing machine capable of switching successive nailing, single nailing and locking with a simple structure, by making a switching pin rotate by one turn, and switching the machine in the first to third positions, so as to place the machine in a successive nailing condition by the first position, single nailing condition by the second position and in a lock condition by the third position. CONSTITUTION: In the case of setting a switching pin 10 to the first position where a notch 10a is placed in a condition toward an idler 8, after ending nailing, when pressing a contact arm 6 is released, the idler 8 is advanced into the notch 10a, to return to the preceding position. Accordingly, a stem 21 of a trigger valve 20 is returned to an off-position, to turn off the trigger valve 20, and the next nailing can be performed. When set in the second position where the notch 10a is directed right oblique downward, by releasing the contact arm 6 after nailing, the idler 8 can not be advanced into the notch part 10a, to provide single nailing. When the switching pin 10 is rotated, till placing the notch 10a directed left diagonal downward, and set in the third position, the rest part 10d of the switching pin 10 hits a protruded part 7b of a trigger 7, to provide a lock condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for locking a so-called continuous hammering, a single hammering and a trigger in an air nailer.

[0002]

2. Description of the Related Art Generally, an air nailing machine is designed to perform nailing only when a contact arm is pressed against an object to be nailed and a trigger is pulled. Therefore, if the trigger is pulled and locked so that it cannot be operated, nailing is not performed even if the contact arm is pushed (trigger lock mechanism). In addition, if the contact arm is pushed while the trigger is being pulled and the contact arm is pushed, the nail will be hammered as many times as necessary, and if the trigger is not returned once for each nailing operation, the next nail will not be hammered. "Single shot" that is not done,
There is provided an air nailer having a mechanism (continuous single switching mechanism) that switches according to the work content and the like. Conventionally, the former technique relating to the trigger lock mechanism includes, for example, an actual flat flat 6-
There is one disclosed in Japanese Patent No. 15980, and the technique relating to the latter continuous / single switching mechanism is, for example, Japanese Utility Model Laid-Open No. 3-591
No. 73 or Japanese Utility Model Laid-Open No. 1-18294 discloses the same.

[0003]

As described above, the air nailing machine provided with both of the above-mentioned mechanisms has been conventionally provided. However, in the past, both the mechanisms were constituted by separate mechanisms, so that the structure was improved. Was complicated, and it was necessary to perform each operation separately, which was troublesome. Therefore, an object of the present invention is to provide an operation switching device for an air nailing machine, which has a simple structure and which can be easily operated to switch between a continuous shot / single shot and a trigger lock.

[0004]

Therefore, according to the invention described in claim 1, the pulling operation of the trigger causes the idler to move.
In an air nailing machine of a type that operates a trigger valve for controlling the operation of the main body of the air nailing machine, a switching pin is provided within a moving range of the trigger and the idler so as to be rotatable around its axis, A first radial direction notch is formed in the switching pin, and the rotation of the trigger and the return of the idler to the front position are allowed depending on the direction of the notch accompanying the rotation of the switching pin around the axis. And a second position that allows the rotation of the trigger and restricts the return of the idler to the front position, and a third position that restricts the rotation of the trigger. Is characterized by.

[0005]

According to the structure of claim 1, when the switching pin is rotated once, the switching pin is switched to the first, second and third positions.
In the first position, the notch allows pivoting of the trigger and return of the idler to the previous position. Since the rotation of the trigger is allowed, pulling the trigger causes nailing, that is, the trigger is unlocked. Further, since the idler can be returned to the front position, the trigger valve is returned to the off position if the pushing operation of the contact arm is canceled even after the trigger is pulled and the trigger operation is continued after the nail driving operation. Therefore, if the contact arm is pushed again while the trigger is pulled, the trigger valve is turned on and the nailing is performed, that is, the hammering is repeated. That is, when the switching pin is set to the first position, the air nailer switches to the continuous hammering state. Here, the front position of the idler means a position that allows the stem of the trigger valve to return sufficiently forward to turn off the trigger valve, and is the same in the following description.

Next, when the switching pin is further rotated from the first position and set to the second position, only rotation of the trigger is allowed due to the notch, and the return of the idler to the front position is restricted by the residual portion. To be done. Here, the residual portion means the residual portion of the switching pin in the axial range in which the notch is formed in the switching pin.

Since the rotation of the trigger is allowed, the trigger can be pulled and operated as in the first position. However, since the return of the idler to the front position is restricted, even if the pushing operation of the contact arm is released after the nailing is completed, the trigger valve cannot be turned off if the trigger is still pulled. In order to turn off the trigger valve, it is necessary to further release the trigger pulling operation and move the idler to the front position. Therefore, in this second position,
Unless the pulling operation of the trigger is released for each nailing operation, the next nailing cannot be performed, that is, the single shot state.

[0008] Generally, unless the idler is returned to the front position, the trigger valve is not turned off, so the striking piston is not returned from the bottom dead center to the top dead center, and therefore the contact arm is pushed next. But nailing is not done.

When the switching pin is further rotated from the second position to the third position, the rotation of the trigger is restricted by the remaining portion of the switching pin, that is, the trigger is locked so that it cannot be pulled. .

As described above, the single shot, the continuous shot and the trigger lock can be switched by simply rotating one switching pin. Therefore, since the continuous single switching mechanism and the trigger lock mechanism, which have been separately configured in the past, are made by a single mechanism, the structure is simplified, and the switching can be performed only by rotating one switching pin. The switching operation is simpler than that of.

[0011]

According to the invention described in claim 1, the mechanism for switching the three operations of the single-shot driving, the continuous driving, and the trigger lock in the air nailer is simplified, and the switching operation is simplified.

[0012]

Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 shows an air nailing machine to which the operation switching device 1 of the present example is applied. In the figure, 2 is a main body portion of the main body portion, and a driver guide 3 is provided at a tip portion (lower portion in the drawing) of the main body portion 2. Are provided in a protruding shape. In addition, a handle portion 4 is provided so as to project in a T-shape substantially at the center of the side surface of the main body portion 2, and a trigger valve 20 for controlling the operation of the main body portion 2 is internally provided at the base portion of the handle portion 4. Has been done. Further, a magazine 5 for accommodating a large number of nails is provided between the handle portion 4 and the driver guide 3 in a bridging manner.

A contact arm 6 is provided on the driver guide 3 so as to be retractable in a state in which the contact arm 6 is protruded by an appropriate amount ahead of the driver guide 3. The rear end portion (upper end portion in the drawing) 6a of the contact arm 6 reaches the vicinity of an idler 8 which will be described later. Since the tip end side is pushed backward, the idler 8 rotates backward around the support shaft 8a.

The trigger 7 is the stem 2 of the trigger valve 20.
1 is rotatably supported by a side portion of the main body portion 2 via a support shaft 7a in a state of facing the position 1. On the back side (top side in the drawing) of the trigger 7, a support shaft 8 supported near the tip of the rotation is provided.
The idler 8 is attached via a to be rotatable in the front-rear direction (vertical direction in the drawing).

The trigger valve 20 functions to control the reciprocating movement of the striking piston 2d by switching the upper surface of the head valve 2a to the atmosphere open state or the compressed air supply state by moving the stem 21 in the axial direction. Have. The stem 21 is urged by a compression coil spring 22 in the direction of returning to the front, that is, in the direction of turning off the trigger valve 20. Therefore, the stem 21 is retracted against the compression coil spring 22, and is returned to the front (off direction) by the biasing force of the compression coil spring 22 and the air pressure acting on the flange portion 21a.

The operation of the trigger valve 20 and the main body 2 will be described below.
The relationship of the operations of will be briefly described. When the contact arm 6 is pushed and the trigger 7 is pulled, the idler 8 is rotated rearward while moving the support shaft 8a rearward, whereby the stem 21 is pushed rearward and retracted by a predetermined amount. When the stem 21 is moved almost to the retracted end, the trigger valve 20 is turned on, whereby the upper surface side of the head valve 2a is opened to the atmosphere. When the upper surface side of the head valve 2a is opened to the atmosphere, the head valve 2a moves upward by the air pressure of the accumulator 2c acting on the lower surface side thereof, whereby the striking piston upper chamber 2b communicates with the accumulator 2c, and Compressed air flows into the striking piston upper chamber 2b, and the striking piston 2d moves downward. A driver 2e is attached to the lower surface of the striking piston 2d, and this driver 2e moves inside the driver guide 3 as the striking piston 2d moves downward, whereby the nails supplied from the magazine 5 are guided by the driver guide. It is struck one by one from the tip of 3.

After the striking piston 2d reaches the bottom dead center and is nailed, when the pushing operation of the contact arm 6 is released, the idler 8 is returned to the front position, whereby the stem 21 of the trigger valve 20 is moved to the off position. The trigger valve 20 is turned off and turned off. Then, the head valve 2a
Air is supplied to the upper surface side of the head valve 2a.
Moves downward, whereby the striking piston upper chamber 2b is cut off from the accumulator 2c, and is opened to the atmosphere via the exhaust port 2h. On the other hand, when the impact piston 2d reaches the bottom dead center, the return air chamber 2 is provided in the impact piston lower chamber 2f.
Since the air pressure of g is acting, the impact piston upper chamber 2b
Is released to the atmosphere, the striking piston 2d is moved upward to return to the top dead center, and the one nailing operation is completed.

When the pushing operation of the contact arm 6 is canceled after the nail has been driven, the idler 8 is returned to the front position and the trigger valve 21 is turned off, whereby the striking piston 2d reaches the top dead center. The nail is returned to the state where the next nailing is possible, but this is the case where the returning of the idler 8 is not regulated at all, and this corresponds to the continuous hammering operation state. That is, in this state of continuous hammering, if the pushing operation of the contact arm 6 is released, the next nailing is possible even if the trigger 7 is still pulled. On the other hand, by restricting the return of the idler 8, the idler 8 cannot be returned to the front position only by releasing the pushing operation of the contact arm 6, and therefore, the trigger valve 20 is not turned off and the next nail driving is performed. It can be made impossible, which corresponds to a single-shot state. The operation switching device 1 of this example is configured to realize the single shot state by restricting the return of the idler 8.

Now, the switching device 1 of this example is mainly composed of the switching pin 10. That is, the main body 2
As shown in FIG. 5, two side supporting edges 2i, 2i parallel to each other are provided in a laterally projecting shape on the side surface of the switch, and a switching pin 10 is provided between the two supporting edges 2i, 2i around its axis. It is rotatably supported. Although not shown, the trigger 7 is provided between the support edges 2i, 2i.
A support shaft 7a for rotatably supporting the switch 7 is supported in a bridging manner, and the switching pin 10 enters a position at a predetermined distance above the support shaft 7, that is, within the movement range of the trigger 7 and the idler 8. It is supported parallel to the vertical position.

Both supporting edges 2i, 2 of the switching pin 10 are
A radial notch 10a is formed in a portion located between i. The notch 10a is formed in a substantially fan-shaped cross section in the range of about 210 ° in the circumferential direction, as shown in FIGS. In addition, the remaining portion in which the notch 10a is formed between the support edges 2i, 2i is particularly referred to as "remaining portion 10d" in the following description.

As shown in FIG. 5, the left end portion of the switching pin 10 shown in the figure projects laterally from the support edge 2i on the left side of the figure, and the operation knob 11 is fixed to the tip thereof.
A compression coil spring 12 is interposed between the operation knob 11 and the support edge 2i on the left side in the figure, and therefore the switching pin 10 is biased to the left side in the figure. On the other hand, a flange portion 10b is formed on the right end portion of the switching pin 10 in the drawing, and the flange portion 10b is formed on the support edge 2 on the right side of the drawing.
It is fitted in the substantially circular recess 2j formed on the right end surface of i by the biasing force of the compression coil spring 12.

On the peripheral surface of the flange portion 10b, as shown in FIG. 6, flat surfaces 10c to 10c are provided at three locations at equal intervals in the circumferential direction.
Are formed at the same distance from the center. On the other hand, the flange portion 10b is provided at one location on the peripheral surface of the recess 2j.
The engaging surface 2k with which the flat surface 10c is brought into contact with is formed at a position that has entered the inner peripheral side. For this reason, the switching pin 10 is positioned at three positions at equal intervals around its axis. These three positions can be arbitrarily selected. That is, by pushing the operation knob 11, the switching pin 1
When 0 is moved to the right in the drawing against the compression coil spring 12, the flange portion 10b is disengaged from the recessed portion 2j, so that the switching pin 10 is rotatable about its axis, and an arbitrary position around the axis is selected. When the pushing operation is released, the switching pin 10 is returned to the left side in the drawing by the compression coil spring 12, and the flange portion 10 is fitted in the recess 2j in a state where the selected one flat surface 10c is in contact with the engaging surface 2k. This causes the switching pin 10 to be non-rotatably locked at a predetermined position around the selected axis. In this way, by positioning the switching pin 10 at three positions around the axis, it is possible to position and fix the direction of the notch 10a at one arbitrarily selected from the three positions.

The positions of the notch 10a at three positions around the axis are set in correspondence with the operations of the trigger 7 and the idler 8 as described below. That is, by rotating the switching pin 10 and selecting the direction of the notch 10b, the air nailing machine can be switched to the continuous hammering state, the single hammering state, and the trigger lock state. The relationship between the direction of the notch 10a and the operation of the trigger 7 and the idler 8 will be described below. 2 shows a continuous shot state, FIG. 3 shows a single shot state, and FIG. 4 shows a trigger lock state.

As described above, the continuous striking state is a state where the return of the idler 8 to the front position is not regulated, and the single shot state is the state where the idler 8 is restrained from returning to the front position and the stem 21 of the trigger valve 20 is regulated. It is realized by blocking the return in the middle position. First, as shown in FIG.
If the switching pin 10 is set at a position (first position) in which a is directed upward (rearward) in the drawing, that is, toward the idler 8, if the pushing operation of the contact arm 6 is released after nailing is completed, Even if the trigger 7 is still pulled, the idler 8 enters the notch 10a and is returned to the front position. Therefore, the stem 21 of the trigger valve 20 is returned to the off position and the trigger valve 20 is turned off. Therefore, the upper surface side of the head valve 2a is opened to the atmosphere and the striking piston 2d is returned to the top dead center, so that the next nailing is possible.

Next, in order to switch to the single shot state, the notch 10a may be set at a position (second position) in which the notch 10a is directed obliquely downward to the right as shown in FIG. In this state where the second position is set, if the pushing operation of the contact arm 6 is released while the trigger 7 is still pulled after nailing, the idler 8 is returned to a certain extent, and the remaining portion 10d of the switching pin 10 is returned. Abut on the notch 10
It becomes impossible to enter the inside of a, so that the idler 8 is not returned to the front position and stops before that. This is because, when comparing FIG. 2 and FIG. 3, the idler 8 in FIG.
Amount corresponding to the depth of a (approximately the radius of the switching pin 10)
It is also clear from the fact that it is located only above FIG.

In this way, since the idler 8 is not returned to the front position, the stem 21 of the trigger valve 20 is not returned to the off position, therefore the trigger valve 20 is not turned off, and the striking piston 2d is not returned to the top dead center. , The next nailing becomes impossible. In order to return the stem 21 to the off position, it is necessary to release the pulling operation of the trigger 7 to move the position of the support shaft 8a forward as shown by the two-dot chain line in the figure, and thereby move the idler 8 forward. is there. This is a single-shot state, so in this case the contact arm 6
The next nail driving cannot be performed unless the pulling operation of the trigger 7 as well as the pushing operation of is canceled for each nail driving.

Next, FIG. 4 shows a trigger lock state. To achieve this trigger lock state, the switching pin 10 is rotated to a position (third position) where the notch 10a is directed obliquely downward and to the left in the drawing. As a result, the remaining portion 10d of the switching pin 10 is substantially in contact with the protruding edge 7b formed on the upper edge of the trigger 7 rearward of the support shaft 7a in the state where the pulling operation is not performed. 7 is blocked by this residual portion 10d and is in a state in which it cannot be rotated, that is, in a trigger lock state.

The protruding edge 7b of the trigger 7 is
Only when the switching pin 10 is set to the third position, the remaining portion 10d contacts the remaining portion 10d, and when the switching pin 10 is set to the first and second positions, the remaining portion 10d protrudes as shown in FIGS. Since it is out of the movement path of the edge 7b,
In the pulling operation of the trigger 7, the protruding edge 7b does not contact the switching pin 10 (residual portion 10d) and the notch 10
The trigger 7 is allowed to rotate, so that the trigger 7 is maintained in the unlocked state.

In this sense, the cutout 10 of the switching pin 10
a can set a sufficient movement difference of the idler 8 between the first position and the second position, and does not hinder the movement of the protruding edge 7b of the trigger 7 at the first and second positions, The range around the axis (210 °) or the cross-sectional shape (substantially fan-shaped) is set so as to satisfy the condition that the protruding edge 7b enters the moving range of the protruding edge 7b only at the position 3 and blocks the movement.

Further, since a notch 7c is formed at the upper end edge of the trigger 7 between the protruding edge 7b and the support shaft 7a, the notch portion 7c is cut from the upper end edge, and therefore, in the continuous hammering state shown in FIG. When the trigger 7 is pulled, the remaining portion 10d of the switching pin 10 enters into the notch 7c so that the pulling operation of the trigger 7 is not blocked. That is, the notch portion 7c functions as a relief for the remaining portion 10d in the continuous shot state.

As described above, in the operation switching device 1 of this example, the switching pin 10 is rotated to rotate the switching pin 10 from the first to the third.
Not only the continuous single switching but also the lock / unlock switching of the trigger 7 can be performed only by selecting the position of. For this reason, the structure is extremely simple and the operation thereof is simple as compared with the case where the continuous / single switching mechanism and the trigger lock mechanism are conventionally constituted by separate mechanisms.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional side view of an air nailer according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view around a trigger and a trigger valve in a continuous shot state.

FIG. 3 is a vertical cross-sectional view around a trigger and a trigger valve in a single shot state.

FIG. 4 is a vertical cross-sectional view around the trigger and the trigger valve in the trigger locked state.

5 is a view taken in the direction of arrow A in FIG. 1, and is a partially sectional front view of the operation switching device.

FIG. 6 is a view taken in the direction of arrow B in FIG. 5, and is a front view of the flange portion.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Operation switching device 2 ... Nail driver main body 2a ... Head valve 2d ... Impact piston 2i ... Support edge 2j ... Recess 2k ... Engaging surface 6 ... Contact arm 7 ... Trigger, 7b ... Projection edge 8 ... Idler 10 ... Switching Pin 10a ... Notch, 10b ... Flange portion, 10c ... Plane,
10d ... Remainder part 20 ... Trigger valve 21 ... Stem

Claims (1)

[Claims] 1. An air nailing machine of a type in which a trigger valve for controlling the operation of the main body of the air nailing machine is operated via the idler by pulling the trigger, in the moving range of the trigger and the idler. A switching pin is rotatably provided around the axis, and a radial notch is formed in the switching pin. The direction of the notch accompanying rotation of the switching pin around the axis causes the trigger to rotate. Motion and a first position that allows the idler to return to the front position, a second position that allows rotation of the trigger and restricts the return of the idler to the front position, and the rotation of the trigger. An operation switching device for an air nailing machine, characterized in that a third position for restricting movement is set.