JP2002120168A - Nailing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nailing machine capable of preventing earth, sand and the like from flowing into a cylinder. SOLUTION: A grip part 3 and a trigger 4 are provided on the lower side of a main body 1, and a cylinder 10 having the rear end opened and provided with a piston 11 to reciprocate, an opening and closing head valve 13 for closing a rear end opening 10A of the cylinder 10, and an annular chamber 15 laid along the outer periphery of the cylinder 10 and having a communicating hole 15T communicating with a grip chamber G are disposed in the main body 1. In this nailing machine, when the head valve 13 is opened by drawing the trigger 4 so that compressed air in the annular chamber 15 is supplied from the rear end opening 10A of the cylinder 10 into the cylinder 10, the piston 11 is moved forward to drive a nail. A filter 20 for purifying the compressed air supplied into the cylinder is provided between the communicating hole 15T of the annular chamber 15 and the rear end opening 10A of the cylinder 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nailing machine which strikes a nail by moving a piston by compressed air.

[0002]

2. Description of the Related Art Conventionally, a cylinder having a rear end opened and provided with a piston capable of reciprocating inside, a head valve which can be opened and closed to close the rear end opening of the cylinder, and a cylinder extending along the outer periphery of the cylinder. There is known a nailer in which a formed annular chamber is provided in a main body.

In such a nailing machine, compressed air is supplied to an annular chamber. When a trigger is pulled, the head valve is opened and compressed air in the annular chamber is opened at the rear end of the cylinder. , Into the cylinder, and the nail is driven by moving the piston forward.

By the way, in such a nailing machine,
The squeezing device and the grip of the nailer are connected by an air hose to supply compressed air to the annular chamber,
Since the air hose is removed at the site, dirt and sand may adhere to the connection plug of the air hose.When the connection plug is connected again, the adhered soil and sand, etc., together with the compressed air may cause the head valve or cylinder to adhere. Will be sent inside. For this reason, there were problems such as damage to the sliding portion of the head valve, air leakage due to poor sealing, and damage to the inner wall of the cylinder, resulting in reduced driving force efficiency.

Therefore, in order to address these problems,
A filter is formed at the air inlet to the clip chamber, or a filter member for capturing external dust is provided near the air inlet in the grip chamber as disclosed in Japanese Patent Publication No. 7-112675. Have been proposed.

[0006]

However, in the case where the filter is provided directly in the air intake or the filter is provided in the grip chamber, a filter having a fine mesh is required due to the small cross-sectional area of the air intake and the grip chamber. However, the use of the above-mentioned method causes a problem that the resistance of the air flow is increased and the output of the nailing machine is reduced. If a filter with a coarse mesh is used, the problem of lowering the output of the nailing machine does not occur, but dust with small particles passes through the filter and enters the sliding portion of the head valve or the cylinder. And the cylinder will be damaged.

The present invention has been made in view of the above circumstances, and has as its object to reduce the output of a nailing machine.
An object of the present invention is to provide a nailing machine that can prevent soil, sand, and the like from being fed into a head valve and a cylinder.

[0008]

To achieve the above object, according to the present invention, a grip portion having a grip chamber to which compressed air is supplied at a lower portion of a main body and a trigger are provided. Is a cylinder having a rear end opened and provided with a piston capable of reciprocating inward, an openable and closable head valve for closing the rear end opening of the cylinder, and the grip formed along the outer periphery of the cylinder and An annular chamber having a communication hole communicating with the chamber, wherein when the trigger is pulled, the head valve is opened and compressed air in the annular chamber is supplied into the cylinder from the rear end opening of the cylinder, and the piston is moved forward. In a nailing machine for driving a nail by moving the cylinder, a pressure supplied into the cylinder is provided between a communication hole of the annular chamber and a rear end opening of the cylinder. Characterized in that a filter for purifying the air.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a nailing machine according to the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a main body of a nailing machine 2, and a grip portion 3 having a grip chamber G and a trigger 4 are provided at a lower portion of the main body 1. The trigger 4 can be pulled when a contact arm (not shown) is pushed backward by a predetermined distance. The grip chamber G is supplied with compressed air from a pressing device (not shown) via an air hose (not shown).

The main body 1 has a cylindrical body case 5 and a cylinder cap 6 attached to a rear portion of the body case 5. A cylinder 10 having an open front and rear end is provided in the body case 5, and a piston 11 is provided in the cylinder 10 so as to be movable in the front and rear direction. Reference numeral 12 denotes a piston rod for driving a nail.

A cylindrical head valve 13 is provided in the cylinder cap 6 so as to be movable in the front-rear direction. The head valve 13 is urged forward by a spring 14 to open a rear opening 10 A of the cylinder 10. It is closed. An annular space R1 is formed between the peripheral wall 13A of the head valve 13 and the cylinder cap 6 outside the rear portion of the peripheral wall 13A.

The space R1 communicates with the outside air via a trigger valve 8 when the trigger 4 is pulled, and communicates with the grip chamber G via the trigger valve 8 when the trigger 4 is released.

A space R2 communicating with the outside air is formed between the inside of the peripheral wall 13A of the head valve 13 and the base 6A at the rear of the cylinder cap 6.

Body case 5 and cylinder cap 6
Between the cylinder 10 and the cylinder 10, extending from the intermediate position of the cylinder 10 to the head valve 13,
An annular chamber 15 is formed along the periphery of. The annular chamber 15 has a communication hole 15T communicating with the grip chamber G and a rear end opening 1 of the cylinder 10.
A filter 20 is provided in a state in which the filter 20 crosses the annular chamber 15 between 0 A and 0 A.

An annular air chamber 16 is formed between the cylinder 10 and the body case 5 and communicates with the air chamber 16 through a front end opening 10B of the cylinder 10.
The air chamber 16 and the inside of the cylinder 10 communicate with each other through a plurality of small holes 10c provided in an intermediate portion of the cylinder 10.

As shown in FIG. 2, the filter 20 includes a filter portion 21 having a fitting hole 21A fitted into the step 10D of the cylinder 10, a seal portion 22 integrally attached around the filter portion 21. It is composed of The seal portion 22 is formed by a groove 2 provided on the inner peripheral wall of the cylinder cap 6.
2M. The filter unit 21 is formed of a porous material such as polyethylene.

Next, the operation of the nailing machine of the above embodiment will be described.

First, the grip portion 3 and the pressing device (not shown) are connected by an air hose (not shown). With this connection, compressed air is supplied from the squeezing device to the annular chamber 15 via the grip chamber G of the grip portion 3.

When a contact arm (not shown) is applied to a position where the nail is driven and the contact arm is pushed backward to pull the trigger 4, the space R1 communicates with the outside air via the trigger valve 8. Annular chamber 1
5, the head valve 13 moves rearward against the urging force of the spring 14 as shown in FIG.

That is, the head valve 13 is opened, and compressed air is supplied from the annular chamber 15 to the cylinder 10 through the rear end opening 10A as shown by an arrow in FIG.
The piston 11 moves forward as shown in FIG. This forward movement of the piston 11 drives the nail.

When the piston 11 moves to the position shown in FIG. 4, the compressed air supplied into the cylinder 10
Through the air chamber 16, and the pressure in the air chamber 16 and the pressure in the cylinder 10 become the same.

When the trigger 4 is released, the space R1 communicates with the grip chamber G of the grip portion 3 via the trigger valve 8, and compressed air is supplied to the space R1. Therefore, the head valve 13 moves forward and is closed as shown in FIG. By closing the head valve 13, communication between the annular chamber 15 and the inside of the cylinder 10 is cut off, and communication between the inside of the cylinder 10 and the space R 2 is made through the inside of the head valve 13.

For this reason, since the space R2 communicates with the outside air, the pressure in the cylinder 10 decreases. On the other hand, since the pressure in the air chamber 16 is applied to the front surface of the piston 11, the piston 11 moves rearward and returns to the initial position shown in FIG.

The compressed air supplied to the grip chamber G flows in the direction of the arrow shown in FIGS. 3 and 4, and flows through the filter 20 into the cylinder 10.
The soil and sand flowing into the grip chamber G are filtered by the filter 2
0 will be removed by the filter unit 21.
For this reason, soil, sand, and the like are
The head valve 1 is prevented from flowing into the inside.
The sliding portion 3 is prevented from being damaged, and the inner wall of the cylinder 10 is prevented from being damaged.

Since the filter 20 is provided in the annular chamber 15, the area of the filter portion 21 of the filter 20 can be increased due to the large cross-sectional area of the annular chamber 15. Can sufficiently secure the flow rate of the compressed air supplied into the cylinder 10 per unit time. For this reason, the nail can be driven out with a predetermined strength.

[0027]

According to the present invention, it is possible to prevent earth and sand from being fed into the head valve and the cylinder, and it is possible to increase the area of the filter. Even if a fine filter is used, the flow rate of the compressed air supplied into the cylinder per unit time can be sufficiently ensured. For this reason, the nail can be driven out with a predetermined strength.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a configuration of a nailing machine according to the present invention.

FIG. 2 is a plan view showing a structure of a filter.

FIG. 3 is an explanatory view showing a state in which a head valve is opened.

FIG. 4 is an explanatory diagram showing a state in which a piston has moved forward.

FIG. 5 is an explanatory diagram showing a state in which the head valve is closed with the piston moved forward.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 3 Grip part 4 Trigger 10 Cylinder 10A Rear end opening 11 Piston 13 Head valve 15 Annular chamber 15T Communication hole 20 Filter G Grip chamber

Claims (1)

[Claims] 1. A grip having a grip chamber to which compressed air is supplied at a lower portion of a main body and a trigger are provided.
In the main body, a cylinder having a piston opened at the rear end and reciprocally movable inside, a head valve that can be opened and closed to close the rear end opening of the cylinder, and formed along the outer periphery of the cylinder. An annular chamber having a communication hole communicating with the grip chamber, wherein when the trigger is pulled, the head valve is opened and compressed air in the annular chamber is supplied into the cylinder from the rear end opening of the cylinder. In a nailing machine for driving a nail by moving a piston forward, a filter for purifying compressed air supplied into the cylinder is provided between a communication hole of the annular chamber and a rear end opening of the cylinder. A nailing machine characterized in that: