JPS6237659Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a safety device for pneumatic nailers, etc., and in particular, the nail is removed only when the two operations of pushing up the contact arm and pulling up the trigger lever are performed. This is an improved trigger device configured to actuate a striking drive mechanism.

This type of nail gun uses air pressure as a driving force to operate a piston, and a driver integrated with the piston is suddenly activated in the nose to drive out one nail with each stroke. The device is configured to perform the following operations. Therefore,
It is effective for efficiently driving a large number of nails, and is widely used for various types of nail driving work, including wooden construction work and wood furniture manufacturing work.

By the way, in this type of nailing machine, the trigger device as a nail driving operation member is designed to press the tip of a contact arm disposed along the nose against the nailed member in order to prevent accidental firing. The trigger valve is triggered for the first time by pushing up this contact arm and pulling up the trigger lever. In other words, in order to push up the trigger valve stem, the trigger lever is pulled up, and the contact lever disposed on the trigger lever is pushed up by the push-up operation of the contact arm. The valve stem is pushed up.

Therefore, the trigger lever and contact lever described above have a complicated structure, and the three components, the trigger lever, contact lever, and contact arm, must be accurately interlocked, making it difficult to design and assemble. Precision is required.

The present invention was devised in view of these circumstances.The contact lever and trigger lever have a simple shape, and an accurate trigger signal can be easily generated, thereby preventing the occurrence of malfunction of the trigger device. The object of the present invention is to provide a trigger device that can be used safely and with sufficient safety.

Furthermore, the present invention attempts to reliably avoid double strikes.

That is, in the present invention, the movement of the through hole for stem escape provided in the contact arm is made to move almost parallel to the stem axis direction of the trigger valve stem.

That is, in the safety device of the present invention, when the trigger lever is pulled up while the contact arm is being pushed up, the trigger operating stem is pushed up by the contact lever disposed on the trigger lever. In the operable nailer, the trigger lever has a proximal end pivoted to the nailer body so as to be rotatable;
The contact lever is rotatably disposed with its base end pivoted to the free end side of the trigger lever, and a through hole corresponding to the tip of the trigger operating stem is provided at the base end side of the contact lever. A cylindrical body is formed to guide the trigger operating stem into the through hole of the contact lever, and when the trigger lever is operated, the edge of the through hole of the contact lever operates the trigger operating stem to the operating position and the operating end of the trigger lever. In the position, after the impact is completed, the trigger operating stem is inserted into the through hole and lowered, the engagement between the contact lever and the stem is released, the stem is returned to the initial position, and the free end of the contact lever is inserted into the trigger lever. The contact lever is made to protrude in the proximal direction and face the end of the contact arm, and is further provided with an inclined surface in a portion of the contact lever that faces the contact arm, and this inclined surface can be contacted by rotating the trigger lever. This is characterized in that when the pivot shaft insertion portion side of the lever is moved, it engages with the upper end of the contact arm and serves as a guide surface that moves the free end upward.

An embodiment of the present invention shown in the drawings will be described below.

Fig. 1 shows a schematic side view of a pneumatic nailer to which the present invention is applied. 1 is the nailer body, and a drive mechanism consisting of a main piston and main cylinder (not shown) is built inside. Furthermore, a driver, which is a nail striking member, is integrally assembled to the main piston. A grip portion 2 is protruded from the back side (right side in the figure) of the middle part of the main body 1, and an air plug 3 is attached to the end portion 2a of the grip portion 2 for connecting a hose for communicating with a compressor, which is a source of compressed air pressure. There is. Further, a nose 4 is provided on the lower end side of the main body 1 and serves as a nail driving portion into which the driver is inserted reciprocally.
That is, a nose hole 5 is formed through the nose 4 so that the nails, which have been loaded in advance one by one into the hole 5, can be struck by a sudden descent of the driver and driven out from the nose tip 4a. It's summery. The nails are supplied into the nose hole 5 by feeding the connected nails one by one from within a magazine (not shown) via a nail supply device 6 disposed on the side of the nose. Further, reference numeral 7 denotes a trigger lever, which is pivotably mounted near the base of the grip portion 2 by a support shaft 8. Therefore, the trigger lever 7 can be pulled up by extending the index finger while gripping the grip 2. A contact lever 10 (not shown in the figure) is rotatably supported on the trigger lever 7 by a fulcrum pin 9. It is faced with stem 12 of 11. The trigger valve 11 is a valve for opening and closing a head valve that opens and closes between the main air chamber and the upper chamber of the piston of the main piston cylinder. When the stem 12 of the trigger valve 11 is in an inactive state, the head valve opens and closes the main channel. The bar and the main piston cylinder are closed off, and the main piston remains at top dead center. on the other hand,
When the stem 12 of the trigger valve 11 is pushed up, the head valve is opened, and the pressurized air in the main chamber is introduced into the upper chamber of the piston of the main piston cylinder, rapidly actuating the main piston, and The driver can be moved downward into the nose hole 5. Reference numeral 13 denotes a contact arm, which is disposed so as to be able to move up and down along the nose, and whose tip 13A is biased by a spring 14 so as to protrude forward (downward in the figure) from the tip 4a of the nose 4. The base end 13B faces the free end of the contact lever 10 attached to the trigger lever 7.

Next, the details of this trigger mechanism will be explained with reference to FIGS. 2 to 8 and, if necessary, the above-mentioned FIG. 1.

FIG. 2 is a diagram showing the trigger mechanism in a non-operated state. The trigger lever 7 has a finger rest part 71
is curved toward the tip 71A side so as to obtain a stable finger-holding state, and upright pieces 72 and 73 are provided which are bent and bent in an L-shape along both side edges of the finger-holding portion 71. (See Figure 8). Further, near the left ends of the rising pieces 72 and 73 in the figure, that is, near the base end of the trigger lever 7, a protrusion 1A protruding from the nailer main body 1 is provided.
It is pivoted by a pivot 8. Therefore, the tip of the trigger lever 7, that is, the right free end in the figure, is vertically movable about the pivot shaft 8.

Further, the contact arm 10 (see FIG. 7) has a pivot shaft insertion portion 1 at its base end, that is, at the right end in the figure.
One end of the band-shaped metal plate is bent into a cylindrical shape so as to form 01, and the base end 1 of the contact arm 13 is formed at the tip, that is, the free end on the left side in the figure.
A portion facing 3B is formed. On this side, the portion of the contact lever 10 near the free end is bent so that the protruding portion 102A forms an abutting inclined surface 102B on the upper surface 71B of the finger hook portion 71 of the trigger lever 7. A ``dog''-shaped bent portion 102 is formed on the side surface. In addition, this bent portion 102 and the insertion portion 101
A through hole 15 is formed in a portion facing the trigger valve stem 12 in between. A fulcrum shaft 9 supported between the upright pieces 72 and 73 is inserted into the pivot shaft insertion portion 101, and rotatably supports the contact lever 10.

The trigger valve 11 is disposed between a conduit 111 communicating with the air chamber and a conduit 112 communicating with the upper chamber of the head valve. Under normal conditions, the stem 12 of this valve 11 is pushed downward by the return spring 113, and the above-mentioned pipes 11
1 and 112, thereby allowing the head valve to close the main air chamber and the piston upper chamber of the main piston cylinder. Furthermore, when the valve stem 12 is pushed upward, the O-ring 114 and the seal ring 1
The pipe 112 that leads to the upper chamber of the head valve is communicated with the atmosphere through a port 116, and the head valve opens to bring the upper chamber of the head valve to atmospheric pressure. Pressurized air within the main chamber acts on the upper chamber of the piston of the main piston cylinder to drive the driver.
A cylindrical body 16 having a flange portion 17 at the lower end is fitted near the protruding end of the valve stem 12 that protrudes in the direction of the trigger lever 7, and the stem 12 is inserted into the through hole 18 of the cylindrical body 16. It has become freely possible. In this cylindrical body 16, the outer diameter dimension L of the flange portion 17 matches the inner dimension between the front rising walls 72 and 73 of the trigger lever 7, and the flange portion 17 is engaged within the space between the rising walls 73 and 73. By matching, the valve stem 12 and the stem through hole 15 of the contact lever 10 can be aligned. Note that the contact lever 10 is connected to each rising piece 72, 7 of the trigger lever 7.
3, and lateral wobbling between these two levers 7 and 10 is suppressed. In addition, the cylindrical body 1
6 is the flange portion 17 and the stepped portion 1 of the valve housing.
The contact lever 10 is biased by a spring 118 disposed between the contact levers 17 and 17 .

Therefore, the operation of the trigger mechanism having the above configuration will be explained next.

First, under normal conditions, that is, when not in operation, the device is in the state shown in FIG. 2 above. That is, in this state, the trigger lever 7 is not pulled up, and the contact arm 13 is not pushed up either. Therefore, in this state, the spring 118 pushes down the trigger lever 7 together with the contact lever 10 in a clockwise direction around the central shaft 8 in FIG.
4 is a stopper part 19 which also serves as a contact guide.
is returned until it abuts and engages. The contact lever 10 is pushed down in a counterclockwise direction around the fulcrum shaft 9, and the protrusion 102A is pressed against the upper surface 71B of the finger hook 71 of the trigger lever 7. Further, the trigger valve stem 12 faces the through hole 15 of the contact lever 10, and the valve 11 is connected to the conduits 111, 112.
The main piston, ie, the driver, remains stopped at top dead center.
Incidentally, at this time, the leading edge of the connecting nails has already been supplied and loaded into the nose hole 5 of the nose 4 by the nail supply device 6.

Next, a case where only the trigger lever 7 is pulled up as shown in FIG. 3 from the state shown in FIG. 2 will be described.

When only the push-up operation of the contact lever 10 is performed as shown in FIG. 3 from the non-operating state shown in FIG. 10 from below, and the lever 10 is rotated clockwise around the fulcrum shaft 9. However, at this time, the trigger lever 7 has not been pulled up yet, so the fulcrum shaft 9 remains in the same position as shown in FIG.
Even with the above-mentioned rotation of the lever 10, the lever 10 does not move to the extent that the valve stem 12 is pushed up. Therefore, it will not be triggered.

Next, the state shown in FIG. 3 is changed to the state shown in FIG. 4 when the trigger lever 7 is fired.
A state in which the lever is further pulled up will be explained. Note that the pushing up operation of the contact arm 13 is performed by bringing the tip 4a of the nose 4 into contact with the surface to be nailed, since the tip 13a of the contact arm 13 protrudes forward from the tip 4a of the nose 4. It is relatively moved against the pressure of the nose 4 so as to be easily pushed upward in the figure against the spring 14.

Then, as the contact arm 13 is pushed upward in the figure, the base end 13B of the lever 13
The contact lever 10 hits the inclined surface 102B formed on the free end side of the contact lever 10 and is pushed up, and the lever 10 is rotated clockwise around the fulcrum shaft 9. By pulling up the lever 7, the lever 7 is rotated counterclockwise around the pivot 8, and when pulled up to the halfway point, the contact that was facing from below the valve stem 12 in the non-operating state shown in FIG. 2 is removed. The through hole 15 of the lever 10 is moved to the right in the figure, and the tip 12a of the valve stem 12 is engaged with the edge 15A of the through hole 15 on the upper surface 10a of the contact lever 10, and the respective levers 7,
10 moves upward, the valve stem 12
The O-ring 114 and the seal ring 115 close off the conduit 111, and the conduit 112 is opened to the atmosphere through the opening 116 and triggered. Thereby, the driver can use compressed air pressure to forcefully hit the nail previously loaded into the nose hole 5 and drive the nail.

Then, from the state shown in FIG. 4 in which the nail is driven by the trigger, the trigger lever 7
As the upward pulling operation progresses and the lever 7 is rotated counterclockwise around the pivot shaft 8,
As shown in FIG. 5, the position of the through hole 15 is aligned below the tip 12a of the valve stem 12 which was engaged on the contact lever 10 at the edge 15a of the through hole 15, so that the valve stem 12 is held in place by the spring. 113 falls into the through hole 15, the trigger valve 11 is switched to the state shown in FIG. 2, and the main piston is returned.

Next, as shown in FIG. 6, when the contact arm 13 is not pushed up and only the trigger lever 7 is pulled up, the trigger lever 7 is rotated counterclockwise around the pivot shaft 8. The fulcrum shaft 9 of the contact lever 10 as it moves
The sides are lifted upwards. By the way, at this time, the tip 12a of the valve stem 12 is facing the through hole 15 formed in the contact lever 10.
Therefore, even if the base end side of the contact lever 10 is moved upward, that is, in the direction of the stem 12 of the trigger valve 11 as the trigger lever 7 is pulled up, the stem 12 will be inserted into the through hole 15 and the trigger The valve 11 itself does not switch in any way and therefore cannot be triggered.

As mentioned above, in this trigger mechanism,
Only when the contact arm 13 is being pushed up prior to the trigger lever 7 being pulled up, the stem 12 of the trigger valve 11 is
is pushed up, the valve 11 is switched, and the trigger can be triggered.The contact arm 13 is pressed against the nailed member and the contact lever 10 is not pushed up, but only the trigger lever 7 is operated. When the above operation is performed, only the cylindrical body 16 is pushed up as shown in FIG.
The stem 12 cannot be pushed up because the trigger lever 7 is inserted into the trigger lever 7.
Even if only the contact arm 13 is pushed up to the top dead center without being operated, the valve stem 12 is still not pushed up as shown in Fig. 3, and therefore the trigger is not triggered. It has a structure that prevents it from being fired by forceful operation.

Further, since the free end of the contact lever 10 is operated to move substantially in parallel by the inclined surface 102 provided on the contact arm 13, the trigger valve stem can be operated reliably. By the way, as explained with reference to FIG. It is in a state where it is very likely to be disengaged from the engagement with the edge 15a. but,
Due to the relative engagement between the flange portion 17 of the cylindrical body 16 and the upright walls 72 and 73 of the trigger lever 7, relative displacement of the valve stem 12 with the trigger lever 7 and, ultimately, with the contact arm 10 due to lateral vibration can be prevented. Therefore, an extremely stable operating state can be easily achieved.

As described above, in the present invention, the trigger signal can be generated reliably, and even if the nose bounces due to the impact during nail driving and the contact arm moves forward, the contact arm is first pushed up and Since the trigger can only be triggered when the trigger valve is then pulled up, double-hitting and erroneous firing can be prevented.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is an external side view of the nailing machine, FIGS. 2 to 6 are longitudinal cross-sectional views of main parts, and FIG. The figure shows the state where only the contact arm is pushed up, and the fourth
The figure shows the trigger state when nailing is performed, FIG. 5 shows the state after nailing is completed, and FIG. 6 shows the state where only the contact lever is pulled up. FIG. 7 shows the contact lever, with A being a plan view and B being a side view. Figure 8A is a sectional view taken along line A-A in Figure 3, Figure 8B
is a sectional view taken along line B-B in FIG. 5. 1... Nailer body, 7... Trigger lever, 1
0...Contact lever, 13...Contact arm, 15...Through hole, 16...Cylindrical body, 102
B...Slope section.

Claims (1)

[Scope of utility model registration request] A nailer capable of pushing up a trigger operating stem using a contact lever disposed on the trigger lever when a trigger lever is pulled up while a contact arm is pushed up. In the above, the trigger lever is rotatably arranged with its base end pivoted to the nailer main body, and the contact lever is rotatably arranged with its base end pivoted to the free end side of the trigger lever. A cylindrical body is formed in which a through hole corresponding to the tip of the trigger operating stem is provided on the proximal end side of the contact lever, and which guides the trigger operating stem to the through hole of the contact lever, and when the trigger lever is operated. The edge of the through-hole of the contact lever operates the trigger operating stem to the operating position, and at the operating end position of the trigger lever, the trigger operating stem is inserted into the through-hole and lowered after the impact is completed, and the contact lever and the stem are connected. When the engagement is released, the stem returns to its initial position, and the free end of the contact lever protrudes toward the proximal end of the trigger lever to face the end of the contact arm, and the contact arm of the contact lever An inclined surface is disposed on a portion facing the contact arm, and when the pivot shaft insertion portion side of the contact lever is moved by rotation of the trigger lever, this inclined surface engages with the upper end of the contact arm and moves the free end upward. A safety device characterized by having a guide surface for movement.