JPH0753903Y2 - Nail driving depth adjustment device for continuous hammering machine - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to nail driving in a continuous hammering type nailing machine in which a nail is driven into an object by continuously striking one nail by using a compressed air impact mechanism. Depth adjusting device.

[0002]

2. Description of the Related Art In a general nail driving machine for driving a nail by an impact mechanism using compressed air, the nail is driven by variably adjusting the amount of protrusion from a nail injection port (nose) of a driver connected to a striking piston. Adjusting the depth. This method increases the volume around the tip of the nose, making it impossible to drive nails into a narrow space, and there is a problem in that adjustment operation is performed near the tip of the nose, which is dangerous.

On the other hand, a nailing machine is known in which a piston slidably accommodated in a movable cylinder is continuously and repeatedly driven to continuously hit a nail by a driver continuously connected to the piston. . In this type of continuous hammering machine, a movable cylinder is movably arranged in the housing, and when the striking piston is driven, the movable cylinder moves for reaction so that compressed air is supplied to and discharged from the movable cylinder. The striking piston is driven repeatedly by. A switching valve mechanism is formed between the outer peripheral surface of the movable cylinder and the housing so as to selectively connect the inside of the movable cylinder to the main chamber and the atmosphere. Along with this, compressed air is introduced into the movable cylinder, and the state in which the compressed air is exhausted is repeated to repeatedly drive the movable cylinder.

In the above switching valve mechanism, a state in which both the air supply and the exhaust are shut off is set between the air supply state and the air exhaust state. This is because the supply air and the exhaust air are opened at the same time and the compressed air that has been supplied is directly exhausted.
This is to prevent the air consumption amount from increasing. Then, when the striking piston in the movable cylinder gradually approaches the bottom of the movable cylinder due to repeated hits and comes into contact with the bumper arranged at the bottom, the striking piston can no longer move downward. At the same time, the movable cylinder is not given a reaction due to the driving of the striking piston. Therefore, the operation of the movable cylinder and the operation of the striking piston are automatically stopped. At this time, the tip of the driver is set to slightly protrude from the nail ejection port.

As described above, according to the conventional continuous hammering type nailing machine, the nail is continuously driven until the continuous hammering is completed, so that the nail is sunk by the amount of the driver. For this reason,
The operator had to stop the continuous hammering on the way and adjust the nail driving depth by experience, which required skill.

[0006]

[Object of the Invention] By the way, looking at the operating states of the striking piston and the movable cylinder until the operation is stopped,
The striking piston operates with a large stroke at the beginning of driving, but the return movement amount gradually decreases, and the operating stroke gradually decreases. Along with this, the operation amount gradually decreases around the position in the neutral state where the movement of the movable cylinder and the above-mentioned air supply and exhaust are shut off, and finally stops at the neutral position. At the stop position of the movable cylinder, the striking piston is in contact with the bumper installed on the bottom of the movable cylinder, so that the stop position of the tip of the driver with respect to the housing becomes constant.

The present invention has been made by paying attention to the above points. The nail driving depth can be adjusted by variably setting the stop position of the movable cylinder, and the adjusting operation is safe and easy. Moreover, it is an object of the present invention to provide a driving depth adjusting device for a continuous hammering type nailing machine which does not increase the volume around the nose.

[0008]

In order to achieve the above object, a driving depth adjusting device of a continuous hammering type nailing machine according to the present invention comprises a striking piston having an upper end closed and a driver integrally connected therein. A hammering machine which has a bumper for movably accommodating it and which stops a striking piston at the bottom, and a movable cylinder slidably arranged in the housing along the nail driving direction and always urged downward. The valve body formed on the inner wall side of the housing, between the valve body formed on the outer peripheral surface of the movable cylinder and the valve body formed on the inner wall side of the housing. When the movable cylinder slides against the bottom dead center position, the inside of the movable cylinder is shut off from the atmosphere and connected to the compressed air supply source, and the movable cylinder moves when the movable cylinder moves to the top dead center position. A switching valve mechanism for disconnecting the inside of the cylinder from the compressed air supply source and opening it to the atmosphere, and a position adjusting device for adjusting the position of the valve element on the housing side along the operating direction of the striking piston. Is characterized by.

In the position adjusting device for the valve element on the housing side, an annular adjuster dial having an external operation is rotatably arranged on the housing, and a height is circumferentially provided on an upper surface or a lower surface of the adjuster dial. While forming a plurality of different stepped portions, a protrusion is formed on the housing side valve body at a position corresponding to the stepped portion, and these plurality of stepped portions are selectively engaged with the protruding portion of the housing side valve body. Alternatively, the position of the housing-side valve element may be variably set.

Further, the valve element on the housing side is provided on the inner peripheral surface of a cylindrical valve which is arranged around the movable cylinder and is slidable in the axial direction, and the valve compresses the inside of the movable cylinder in the initial position. It may be arranged such that it is located at a position where it is cut off from the air supply source and moves to a position where it is connected to the compressed air supply source inside the movable cylinder during operation.

[0011]

According to the above construction, compressed air is supplied into the movable cylinder, whereby the striking piston is driven in the nail driving direction to strike the nail. At the same time, the movable cylinder moves upward due to the reaction of the driving of the striking piston.
When the movable cylinder moves upward, the inside of the movable cylinder is switched to be opened to the atmosphere, so that the differential pressure between the upper and lower surfaces of the striking piston is reversed and the striking piston moves upward. At this time, the driving reaction force of the striking piston also disappears, so that the movable cylinder moves downward again. At the bottom dead center, the switching valve mechanism again switches the inside of the movable cylinder so as to connect it to the compressed air supply source, so that the striking piston is driven and the movable cylinder also moves upward. The above operation is repeated, and the nails are repeatedly hit.

By the way, the switching valve mechanism is set in a neutral state in which air supply and exhaust are shut off, and when the striking piston hits the bumper and stops, the movable cylinder is in the neutral position. By adjusting the position of the valve element on the housing side along the operating direction of the striking piston, the position of the movable cylinder and the position of the striking piston can be variably set. Since the driving depth of the nail is determined by the stop position of the striking piston, the driving depth of the nail can be adjusted by the position adjusting device. Therefore, no skill is required for the nailing work.

When the position adjusting device for the valve element on the housing side is performed by the adjuster dial, the adjusting operation can be performed safely and easily, and the volume around the nose is not increased.

Further, the valve element on the housing side is provided on the inner peripheral surface of the valve which is arranged around the movable cylinder and connects or disconnects the switching valve and the compressed air supply source by sliding in the axial direction thereof. In this case, the nail driving depth can be adjusted by variably setting the sliding end position when the valve is in communication.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a main part of a continuous hammering type nailing machine, in which the upper end is closed in a housing 1. A movable cylinder 2 slidably arranged in the nail driving direction (vertical direction in the figure), a striking piston 4 slidably accommodated inside the movable cylinder 2 and integrally coupled with a driver 3, and a compression cylinder. A main chamber (compressed air storage chamber) A that is connected to an air supply source (not shown) is arranged, and the movable cylinder 2 and the impact cylinder 2 are struck by the switching mechanism described below using the compressed air in the main chamber A. 2 are continuously operated, and the nails 6 in the nose portion 5 continuously provided below the housing 1 are repeatedly hammered.

The movable cylinder 2 is formed into a bottomed cylinder having an upper part closed by a cylinder head 7 and a bumper 8 arranged at the bottom, and a coil spring 9 is provided between the cylinder head 7 and the upper bottom of the housing 1. The movable cylinder 2 is attached and constantly urged downward by the spring force of the coil spring 9. Further, an opening 10 is formed in the upper side wall of the movable cylinder 2, and the switching valve mechanism 11 switches the supply / discharge of compressed air to / from the opening 10.

The switching valve mechanism 11 is composed of a valve body 12 formed on the outer peripheral surface of the movable cylinder 2 and a sleeve-like valve body 13 formed on the inner wall side of the housing 1. That is, the valve body 12 of the movable cylinder 2 is formed by the upper and lower sealing members 14 and 15 which are provided around the outer peripheral surface thereof. On the other hand, the inner diameter of the central portion 16 of the inner peripheral surface of the sleeve-shaped valve body 13 is such that the sealing members 14, 1 of the movable cylinder 2
The upper and lower parts 17 and 18 are formed so large that the inner diameters of the upper and lower portions 17 and 18 are large enough to form a gap between the sealing members 14 and 15. When the movable cylinder 2 is at the bottom dead center position (see FIG. 1), the lower sealing member 15
Is removed downward from the central portion 15 of the inner peripheral surface of the sleeve-shaped valve element 13, the interior of the movable cylinder 2 is shut off from the atmosphere and connected to the main chamber A, and the movable cylinder 2 moves to the top dead center side. At this time (see the dotted line in FIG. 2), the upper sealing member 14 is disengaged upward from the central portion 16 of the inner peripheral surface of the sleeve-shaped valve body 13, so that the opening 1 is formed in the movable cylinder 2.
Shut off from main chamber A via 0 and housing 1
It is set so as to be opened to the atmosphere through the upper exhaust hole 18. It should be noted that when the movable cylinder 2 slides, as shown in FIG.
As described above, the upper and lower sealing members 14 and 15 are simultaneously brought into contact with the central portion 16 of the inner peripheral surface of the sleeve-shaped valve body 13 so as to be in a neutral state in which air supply and exhaust are blocked.

Next, on the outer peripheral side of the sleeve-shaped valve body 13, an annular upper chamber 21 and a lower chamber 22 for accommodating the main valve 20 slidably in the axial direction are formed so as to vertically oppose each other. A valve guide 23 is arranged outside the chamber 21, and the lower chamber 2
An air passage 24 communicating with the trigger valve is formed at the bottom of the opening 2. The main valve 20 is formed in a tubular shape, and an opening 25 is formed through the lower part of the side wall of the main valve 20. When the main valve 20 is at the lower end position of the lower chamber 22 (see FIG. 1), the main chamber A and the switching valve mechanism 11 are shut off, and when the main valve 20 moves to the upper end position (see FIG. 2). ) Is configured to communicate between the main chamber A and the switching valve mechanism 11 via the opening 25. Further, a spring 27 that constantly urges the main valve 20 downward is disposed between the protruding edge 26 at the center of the outer peripheral wall of the main valve 20 and the lower surface of the valve guide 23.

The main valve 20 is normally in the lower position by the spring 27, and a trigger valve (not shown) is operated based on the pulling operation of the trigger lever 28 to move the air from the air passage 24 into the lower chamber 22. The air pressure of the supplied compressed air resists the spring 27 and moves upward as shown in FIG. When the compressed air is exhausted by the release operation of the trigger lever 28, the main valve 20 is again moved downward by the spring 27.

Next, there is provided a position adjusting device for adjusting the position of the sleeve-shaped valve body 13 on the housing 1 side along the operating direction of the striking piston 4. This position adjusting device is composed of an adjuster dial 30 and a sleeve-shaped valve body 13, and the adjuster dial 30 is formed in an annular shape and is rotatable between the housing body 1a and the housing cap 1b above it. It is arranged. As shown in FIGS. 4 (a) and 4 (b), the adjuster dial 30 is formed with an operation portion 31 that is exposed to the outside of the housing 1. Two step portions a and b having different heights are formed in the direction. The steps having the same height are arranged on the opposite sides of the center. g is a guide slope.
On the other hand, as shown in FIGS. 5 (a) and 5 (b), outwardly projecting projections 33 are formed on the outer peripheral surface of the sleeve-shaped valve body 13 so as to project in a fan shape on opposite sides. The notch 34 between the protrusions 33 has a circumferential length that is longer than the circumferential length of the higher step portion a of the adjuster dial 30, and also at both ends of each protrusion 33. A guide slope g is formed. The protrusion 33 is sandwiched between the adjuster dial 30 and the upper end of the valve guide 23 in the upper chamber 21 of the main valve housing 1, whereby the position of the sleeve-shaped valve body 13 in the housing 1 is determined. Therefore,
By selectively engaging the step portions a and b of the adjuster dial 30 with the protrusion 33 of the valve element 12 on the housing 1 side,
The position of the valve element 12 on the housing 1 side can be variably set. That is, as shown in FIG. 1, when the high step portion a of the adjuster dial 30 is engaged with the upper surface of the protrusion 33 of the housing 1 side valve body 12 by the operation of the operation portion 31, the sleeve-shaped valve body 13 is at a lower position. And the lower step b is engaged with the upper surface of the protrusion 33 of the valve element 12 on the housing 1 side as shown in FIG. 6, the sleeve-shaped valve element 13 is set to a high position.

In the above structure, the main valve 20 is located at the lower end position of the lower chamber 22 of the valve housing 1 by the spring force of the spring 27 before the nailer is started, and the main chamber A and the switching valve mechanism 11 are shut off from each other. ing. Similarly, the movable cylinder 2 is also at the bottom dead center position due to the spring force of the coil spring 9. When starting the nail driver, the trigger lever 28
To operate the trigger valve to supply compressed air from the air passage 24 into the lower chamber 22 of the main valve 20. As a result, the main valve 20 moves upward as shown in FIG. 2, the main chamber A communicates with the switching valve mechanism 11 through the opening 10 of the main valve 20, and the compressed air in the main chamber A opens in the movable cylinder 2. Suddenly supplied from the portion 10 to the inside. Therefore, the striking piston 4 is driven in the nail driving direction to strike the nail 6 in the nose portion 5. At the same time, the movable cylinder 2 moves upward as shown by the dotted line against the coil spring 9 due to the reaction of the driving of the striking piston 4. When the movable cylinder 2 is moved upward, the upper sealing member 14 is disengaged upward from the central portion 16 of the inner peripheral surface of the sleeve-shaped valve body 13, so that the inside of the movable cylinder 2 is blocked from the main chamber A and communicates with the exhaust hole 18. Since the switching is performed, the pressure balance for the upper and lower surfaces of the striking piston 4 is reversed, and FIG.
The striking piston 4 moves upward as shown in. At this time, since the driving reaction force of the striking piston 4 also disappears, the movable cylinder 2 moves downward again by the spring force of the coil spring 9. When the bottom dead center is reached, the switching valve mechanism 11 again shuts off the inside of the movable cylinder 2 from the atmosphere and switches the connection to the main chamber A, so that the striking piston 4 is driven.
At the same time, the movable cylinder 2 also moves upward. The above operation is repeated, and the nail 6 is repeatedly hit.

The striking piston 4 operates with a large stroke at the beginning of driving, but the returning movement amount gradually decreases as the nail 6 is driven, the operating stroke gradually decreases, and finally the bottom of the movable cylinder 2 is moved. The bumper 8 installed on the vehicle is stopped and stopped. The movable cylinder 2 also gradually decreases in operation amount around the neutral position where the supply air and the exhaust gas are cut off, and finally stops in the neutral position shown in FIG. 3 in synchronization with the stop of the striking piston 4.

By the way, the stop of the striking piston 4 is determined by the stop position (neutral position) of the movable cylinder 2, and the neutral position is determined by the position of the sleeve-shaped valve body 13, so that the adjuster dial 30 of the position adjusting device is adjusted. By selecting engagement between the stepped portions a and b and the protrusion 33 of the sleeve-shaped valve body 13 by rotating operation, the stop height position of the striking piston 4 can be set as shown in FIG. 1 or 6. You can Since the nail driving depth is determined by the stop position of the striking piston 4, the nail driving depth can be adjusted by the position adjusting device. Also,
The dial adjusting operation can be performed safely and easily, and the volume around the nose portion 5 is not increased.

A step portion is formed on the upper surface of the adjusting dial 30, and the step portion and the projection 33 of the sleeve-shaped valve body 13 are formed.
Needless to say, the position of the sleeve-shaped valve body 13 may be adjusted by engaging with the lower surface of the.

Next, FIG. 7 shows an example in which the sleeve-shaped valve element is integrally formed with the main valve to form a valve element (sleeve-shaped valve element portion 13a) on the inner peripheral side of the housing. The switching valve mechanism 11a Is formed between the movable cylinder 2 and the sleeve-shaped valve body portion 13a. That is, upper and lower sealing members 14a and 15a are provided around the outer peripheral surface of the movable cylinder 2, whereas the inner diameter of the central portion 16a of the inner peripheral surface of the sleeve-shaped valve body portion 13a is small and the upper and lower portions 17a, 18
The inner diameter of a is formed large. The neutral state is set in the same manner as in the example of FIG. The same members as those shown in FIG. 1 are designated by the same reference numerals.

The main valve 20a is a housing 1
Is formed in the lower chamber 22a and an annular valve guide 23a that is vertically slidably arranged above the lower chamber 22a and is slidably guided in the axial direction. As shown in FIG. 8, the upward movement of the valve 20a is restricted by the engagement of the inner peripheral inclined surface 35 of the valve guide 23a with the outer peripheral inclined surface 36 of the main valve 20a. Therefore, the upper end of the main valve 20a is determined by the position of the valve guide 23a.

Next, the position adjustment of the sleeve-shaped valve body portion 13a is constituted by the adjuster dial 30a and the valve guide 23a. That is, the adjuster dial 30a has the operation portion 31a as shown in FIGS. 9 (a) and 9 (b), and has two step portions a having different heights in the circumferential direction on the lower surface.
b is formed. On the other hand, as shown in FIGS. 10 (a) and 10 (b), step portions a, b, and c having different heights are also formed on the upper surface of the valve guide 23a. Therefore, similarly to the above-described example, the height position of the valve guide 23a is changed by selectively engaging the adjuster dial 30a with the step portions a, b, c of the valve guide 23a by the rotation operation of the operation portion 31a. Can be adjusted. Main valve 20a
Since the upper moving end of the main valve 20a is determined by the position of the valve guide 23a, the upper moving end of the main valve 20a can be variably set by the position adjusting device, and thus the position of the sleeve-shaped valve body portion 13a can be adjusted. .

Also in the above-mentioned structure, the trigger lever is pulled to operate the trigger valve to move compressed air from the air passage 24a to the lower chamber 22 of the main valve 20a as shown in FIG.
When the main valve 20a is moved upward by supplying the fluid into the inside a, the central portion 16a of the inner peripheral surface of the sleeve-shaped valve body portion 13a is removed from the lower sealing member 15a of the movable cylinder 2, and the inside of the movable cylinder 2 is inside the main chamber A. Compressed air is rapidly supplied to the inside from the opening 10 of the movable cylinder 2. Therefore, the striking piston 4 is driven in the nail driving direction to strike the nail in the nose portion. At the same time, the movable cylinder 2 moves upward against the coil spring 9 due to the reaction of the driving of the striking piston 4, and the upper sealing member 14a moves upward by being disengaged upward from the central portion 16a of the inner peripheral surface of the sleeve-shaped valve body portion 13a. Since the inside of the cylinder 2 is opened to the atmosphere, the striking piston 4
Moves upward and the movable cylinder 2 moves downward. Then, similarly to the above-described example, the switching valve mechanism 11 operates to cause the switching valve to supply or exhaust compressed air to or from the movable cylinder 2 in response to the vertical movement of the movable cylinder 2, thereby moving the striking piston 4 up or down. The nail is hammered continuously by the interaction that the movable cylinder 2 moves up and down by the driving of the striking piston 4, and the movable cylinder 2 also stops at the neutral position when the striking piston 4 stops. The main valve 20a is held at the upper position during this continuous striking.

The stop of the striking piston 4 is determined by the stop position (neutral position) of the movable cylinder 2, and the neutral position is the sleeve-shaped valve body portion 13a.
Is determined by the position adjusting device, the position adjusting device selects the height of the position of the sleeve-shaped valve body portion 13a, thereby setting the stop position of the striking piston 4 as shown in FIGS. 7 and 11, and driving the nail. The depth can be adjusted.

In the case of the above construction, as in the case of FIG. 1, a protrusion (not shown) is formed on the outside of the sleeve-shaped valve body portion 13a of the main valve 20, and the protrusion and the adjuster are formed. The position may be adjusted by selectively engaging the step portion of the dial 30. As described above, the structure of the valve body position adjusting device on the housing side is not necessarily limited to the above-described illustrated example.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of a nail driving depth adjusting device of a continuous hammering nailer according to the present invention.

FIG. 2 is an explanatory diagram of a mode of continuous hammering operation of the nail driver.

FIG. 3 is an explanatory diagram of a neutral position of a movable cylinder of the nail driver.

4A and 4B are a plan view and a side view of an adjuster dial, respectively.

5A and 5B are a plan view and a side view, respectively, of a sleeve-shaped valve body.

FIG. 6 is an explanatory view of an adjustment mode of the nail driving depth adjusting device.

FIG. 7 is a cross-sectional view of main parts of another example of the nail driving depth adjusting device.

FIG. 8 is an explanatory view of a continuous hammering operation mode of the nailing machine of FIG.

9A and 9B are a plan view and a side view of an adjuster dial, respectively.

10A and 10B are a plan view and a side view of a valve guide, respectively.

11 is an explanatory view of an adjustment mode of the nail driving depth adjusting device of FIG.

[Explanation of symbols]

 2 movable cylinder 3 driver 4 striking piston 12 valve element of movable cylinder 13 valve element on the housing side (sleeve valve element) 13a sleeve valve element 20 main valve 30 adjuster dial 33 protrusion

Claims (3)

[Scope of utility model registration request] 1. A striking piston having an upper end closed and a driver integrally connected therein is slidably accommodated therein, and a bottom has a bumper for stopping the striking piston and sliding in the housing along a nail driving direction. In a continuous hammering nailing machine equipped with a freely arranged movable cylinder which is always urged downward, between a valve body formed on the outer peripheral surface of the movable cylinder and a valve body formed on the inner wall side of the housing. In addition, when the valve body on the outer peripheral surface of the movable cylinder slides on the valve body formed on the inner wall side of the housing, the inside of the movable cylinder is shut off from the atmosphere when the movable cylinder is at the bottom dead center position. In addition, a switching valve mechanism is formed which is connected to the compressed air supply source and shuts off the inside of the movable cylinder from the compressed air supply source to the atmosphere when the movable cylinder moves to the top dead center position. , The housing side of the valve member position driving depth adjusting device barrage type nailing machine, characterized in that a position adjusting device that adjusts along the operation direction of the striking piston of. 2. A position adjusting device for a valve element on the housing side rotatably disposes an annular adjuster dial having an external operation on the housing, and has a height in a circumferential direction on an upper surface or a lower surface of the adjuster dial. While forming a plurality of different stepped portions, a protrusion is formed on the housing side valve body at a position corresponding to the stepped portion, and these plurality of stepped portions are selectively engaged with the protruding portion of the housing side valve body. 2. The driving depth adjusting device for a continuous hammering type nailing machine according to claim 1, wherein the position of the valve element on the housing side is variably set by combining them. 3. A valve body on the side of the housing is provided on an inner peripheral surface of a cylindrical valve which is arranged around a movable cylinder and is slidable in an axial direction, and the valve is compressed with the switching valve in an initial position. 2. A position which is cut off from an air supply source and which is arranged so as to move to a position where the switching valve and the compressed air supply source are connected when operating.
A driving depth adjusting device for the continuous nailing machine described in the above.