JPH0525825Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is a fastener driving tool that drives a nail-shaped fastener into a target object such as concrete by driving a piston member by the explosive gas pressure of gunpowder. In particular, the present invention relates to a fastener driving tool whose driving force can be adjusted.

[Prior Art] A piston member and a fixing device are fitted into a gun cavity having a chamber at the tail end, and a firing mechanism provided at the rear fires an empty cartridge loaded into the chamber to drive the piston member. In order to accurately drive fasteners of various lengths into objects made of various materials using a fastener driving tool for driving fasteners, it is necessary to adjust the driving force of the fastener, and there is a means to do so. One possibility is to change the amount of gunpowder in the empty cartridge.

However, it is undesirable to produce many types of blank packages with different amounts of explosives, as it is not only uneconomical but also complicated in terms of use and storage.

To address this issue, Tokuko Sho developed a fastener driving tool that was configured to adjust the fastener driving force by changing the volume of the initial combustion chamber formed between the chamber in the gun barrel and the rear end of the piston member. Publication No. 43-2194, Special Publication No. 43
-7506 Publication, Special Publication No. 59-49879, Special Publication Sho
It is presented in Publication No. 62-6075, etc.

[Problems to be solved by the invention] However, the method proposed in Japanese Patent Publication No. 43-2194 is an explosion system in which sealing pieces of different lengths are replaceably arranged at the base end of the explosive gas exhaust groove. This structure adjusts the driving force of the fastener by changing the gas discharge start position, and the structure is complex and it is difficult to replace the sealing piece, especially when adjusting on site. It has to be prepared separately and is not easy to work with. In addition, the special public interest public
The one proposed in Publication No. 7506 has a configuration in which the barrel with a chamber at the tail end is once removed and then inserted and fixed in a different position to change the volume of the initial combustion chamber to adjust the driving force of the fixing tool. However, each time the fixing tool is driven in, the gun barrel must be pulled out and then returned to a predetermined position to be fixed, making the operation extremely difficult and unsuitable for continuous work.
Furthermore, in the one disclosed in Japanese Patent Publication No. 59-49879, a pin extending in the axial direction is provided on the tail end surface of a piston member fitted into a gun cavity having a chamber at the tail end.
In addition, a pin fitting hole is provided at the tail end of the gun barrel, and a height-adjustable indicator for the pin is provided on the breech closing piece, so that the protruding length of the pin from the tail end of the gun barrel can be adjusted by the breech closing piece. By changing the volume of the initial combustion chamber, the driving force of the fixing tool is adjusted.Since the hole for the pin is formed along the chamber, the wall thickness of the chamber is thinner and the strength is increased. If the chamber is made thicker in an attempt to solve this problem, the diameter of the gun barrel will increase, making the entire tool larger and heavier, which is undesirable. Furthermore, the special public service of 1982-
The device disclosed in Japanese Patent No. 6075 has a stopper device that is movable in a reciprocating manner and that returns the piston member to its original position after being driven into the body.
A structure that adjusts the driving force of the fixing tool by changing the volume of the initial combustion chamber by changing its position, and an inner tube fitted with a piston and having a flange at the tail end is arranged inside the body. An adjustment device is provided that is connected to the barrel by screwing and acts on the inner tube by rotation, and is fixed by changing the volume of the initial combustion chamber formed between the flange of the inner tube and the chamber at the tail end of the barrel. The structure is complicated because the stopper device is arranged inside the body so that it can reciprocate, and the position of the stopper device arranged inside the body can be changed from the outside. A more complicated and difficult-to-operate mechanism had to be adopted, and the flange not only needed to be heat resistant because it formed the initial combustion chamber, but it also became immobile due to gunpowder residue from the explosion. I'm worried.

It is an object of the present invention to solve these problems and provide a fastener driving tool with good operability that can easily and reliably adjust the fastener driving force.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention has a piston member fitted in a gun cavity having a chamber at the tail end, and a slot extending in the front-rear direction. A gun barrel having a threaded portion on the outer peripheral surface of the tail end is fitted into the cylindrical hole of the housing so as to be movable and rotatable in the longitudinal direction, and extends in the longitudinal direction, with the tail end positioned forward of the tail end of the slot. The cylinder body has a slot and a threaded part on the inner circumferential surface of the tail end, and the threaded part is screwed into the threaded part to connect the housing and the gun barrel.
and the tip is placed in either a position where it penetrates the slot in the barrel and protrudes into the gun cavity, or a position where it is pulled out from these and retracted into the slot in the barrel. A return member is provided in the housing at a position where the return member fits into the slot of the barrel when the barrel is advanced, and the piston member is tightly fitted into the gun cavity and extends into the barrel. It is characterized by having a piston at the proximal end that engages with the return member.

[Operation] When the gun barrel is pulled out to the front of the housing after driving, the piston member and the cylinder body collide with the return member and stop, creating an initial predetermined volume between the chamber at the tail end of the barrel and the rear end of the piston member. Form a combustion chamber.
Next, when the gun barrel is pushed directly into the housing, the piston member and the cylinder body also retreat together, forming the initial combustion chamber and returning to the predetermined position before driving.

When the return member is placed in a position where it is inserted into the slot of the barrel without passing through the slot in the barrel and the barrel is pulled out, the gun stops when the tail end of the slot hits the return member. At this time, the gun barrel is rotated as many times as necessary, one rotation being one unit, and moved in the axial direction. After changing its relative position with the barrel, the barrel and the barrel are pushed into the housing, and then the return member is moved into the gun cavity. The volume of the initial combustion chamber is changed by placing the barrel in the protruding position, pulling it out until the piston member and cylinder stop against the return member, and pushing the barrel into the housing again.

[Example] Next, the present invention will be described based on an example shown in the drawings.

1 to 5 show an embodiment of the present invention, in which a fastener driving tool 1 has a gun barrel 4 fitted into a cylindrical hole 3 of a housing 2 so as to be movable and rotatable in the longitudinal direction. A firing mechanism (not shown) is disposed at the rear of the handle frame 5 and at the rear of the handle frame 5. The barrel 4 has a chamber 7 into which a blank cartridge 6 is loaded at the tail end.
A groove 8 is formed extending in the front-rear direction from a little forward of the hole to the tip edge, and a threaded portion 9 is formed on the outer peripheral surface of the tail end, and a piston member is installed in the barrel 10. 11 is fitted so as to be movable in the front-back direction. This piston member 11 is composed of a large-diameter piston 11a at the base end and a piston rod 11b extending forward thereof, and has a gun cavity 10.
The piston 11a is tightly fitted in the. Further, the barrel 4 as a whole is formed to have a smaller diameter than the cylindrical hole 3 of the housing 2, and has a larger diameter portion 1 rearward than the threaded portion 9.
2 and a sub-housing 13 that is fitted onto the tip of the housing 2 and protrudes forward. It has 14.

Further, a cylindrical body 16 is formed with a slot 15 extending in the front-rear direction from the central part to the tip edge and overlapping the slot 8, and a threaded part 17 is formed on the inner peripheral surface of the tail end. A threaded portion 17 is screwed onto the threaded portion 9 and inserted into the spacer 14 so as to be movable in the front and rear direction.

Furthermore, the tip passes through the slot 8 of the gun barrel 4 and enters the gun cavity 10.
The cylindrical body 1 is extracted from the protruding position or
A return member 18 is provided at the tip of the housing 2 to be placed in one of the retracted positions in the slots 15 of the housing 2. This return member 18 has one opening 19a connected to the cylindrical hole 3, as shown in FIGS. 2 to 4, for example.
A rod-shaped return member body 20 is disposed within the rod in a tubular holder 19 that is exposed to the housing 2 and fixed to the housing 2.
is urged in the direction of the cylindrical hole 3 by a coil spring 21 interposed between the two, and is fitted so as to be movable in the axial direction, and has an end face shape extending perpendicularly to the axial direction at the base of the return member main body 20. An engaging piece 23 having a matching groove 22 is fixed by a snap spring 24, and a flange 26 having a pair of parallel notches 25 into which the engaging groove 22 fits is formed on the holder 19. Therefore, as shown in FIG. 2, when the engagement groove 22 is fitted into the notch 25 of the flange 26 and the bottom surface 22a of the engagement groove 22 is in contact with the lower surface 26a of the flange 26, the return member is removed. The main body 20 is fixed at a position where the tip thereof passes through the slot 8 of the gun barrel 4 and projects into the gun cavity 10. Furthermore, when the engaging piece 23 is grabbed and pulled against the biasing force of the coil spring 21, the engagement between the engaging groove 22 and the notch 25 of the flange 26 is released, and then the engaging piece 23 is pulled as it is. 90 with 23 as the center
When the engagement piece 23 is rotated once and released, the engagement piece 23 is again fixed by the biasing force of the coil spring 21 with the distal end surface 23a in contact with the lower surface 26a of the flange 26, as shown in FIG. Therefore, by setting the engagement groove 22 to a predetermined depth in advance, the tip of the return member main body 20 can be fixed at a position where it projects only into the slot 15 of the barrel 16 without entering the slot 8 of the barrel 4. can.

As shown in FIG. 1, this embodiment is configured in this manner, in which the empty cartridge 6 is loaded into the chamber 7, and the secondary housing 13 is fitted in the secondary housing 13 so as to be movable back and forth and placed in front of the tip of the gun barrel 4. A fixing tool 27 is loaded into a gun barrel 30, a firing mechanism is operated to fire a blank cartridge 6, a piston member 10 is driven by the pressure of the explosive gas, and the fixing tool 27 is driven into a target object 28 such as concrete.

When the gun barrel 4 is pulled forward when driving is completed, the piston member 11 and the cylinder body 16 move forward together, and the front end surface of the piston 11a hits the return member 18, so that the piston member 11 stops. However, when the barrel 3 is further pulled out, the tail end of the slot 15 hits the return member 18 and the barrel 16 is stopped.
The barrels 4, which are connected to each other by the threaded portions 9 and 17, also stop at the same time. Therefore, when pushed into the housing 2 as it is, the piston member 11 and the cylinder body 1
6 also retreats together with the gun barrel 4 and returns to the predetermined position before driving, with the initial combustion chamber 29 of the predetermined volume initially set being formed.

Here, a case will be described in which the driving force is adjusted by increasing the volume of the initial combustion chamber 29 from the state shown in FIG. 6, where the volume is the minimum.

First, operate the return member 18 and insert the tip of the return member 18 into the barrel 4.
The barrel 10 is further pulled out from the slot 8 and retracted to a position where it slightly protrudes into the cylindrical hole 3, and the barrel 4 is moved so that the cylindrical body 16 and the tail end of the slot 15 are in the return member 18, as shown in FIG. Pull it out until it hits and stops. Next, rotate the gun barrel 4 as much as necessary, with each rotation being one unit.
The return member 18 is inserted into the slot 15 and moved toward the tail end relative to the fixed cylinder 16, for example, to the position shown by the chain line in FIG. 7, and in this state the barrel 4 is pushed into the housing 2. It's crowded. 8th next
As shown in the figure, the return member 18 is passed through the slot 8 of the gun barrel 4 and protrudes into the gun cavity 10, and the piston member 11 and the cylinder body 16 are again inserted into the return member 18.
When the gun barrel 4 is pulled out until it hits and stops, the barrel 16 advances to the same position as shown in FIG. Stop at a position. Therefore, the volume of the initial combustion chamber 29 formed between the cartridge chamber 7 and the rear end surface of the piston 11a increases, and the driving force can be weakened.

Although the case where the volume of the initial combustion chamber 29 is increased has been described here, if the barrel 4 is rotated in the opposite direction and moved forward relative to the cylinder body 16, the initial combustion chamber 29 is increased.
The driving force can be increased by reducing the volume of the ball.

In this way, the volume of the initial combustion chamber 18, that is, the driving force of the piston member 11, can be changed very easily by simply rotating the gun barrel 4, moving the position of the cylinder body 16 relative to the gun barrel 4, and operating the return member 18. Since it can be adjusted, fixing tools 16 of various lengths can be accurately driven into objects made of various materials without too much or too little, and the cylinder body 16 for changing the volume of the initial combustion chamber 29 can be adjusted. Initial combustion chamber 29
Because it does not form a wall, it does not require heat resistance and can be manufactured at low cost, and there is no fear that gunpowder residue from an explosion will adhere and cause it to become inoperable.

Note that the return member 18 is not limited to the above-mentioned embodiment, and the return member 18 is not limited to the above embodiment.
A position in which the barrel 16 protrudes into the gun cavity 10 through a slot 8 formed in
Any other configuration may be used as long as it can be placed selectively in either the retracted position after being fitted into the slot 15. Further, for example, by forming an axial groove on the wall surface of the cylinder hole 3 and elastically supporting a ball that fits into the groove on the outer circumferential surface of the large diameter portion 12 at the tail end of the barrel 4, When the gun barrel 4 is rotated to adjust the driving force, it is possible to know that the gun barrel 4 has been rotated exactly one rotation just by the feel of the hand.

[Effects of the invention] According to the invention, the volume of the initial combustion chamber can be easily and reliably changed simply by changing the position of the return member and rotating and moving the gun barrel back and forth.
Therefore, various fasteners can be reliably driven into objects made of various materials by adjusting the driving force of the piston member with a simple operation. In addition, the structure is not complicated and the overall size of the tool does not need to be increased, and the cylindrical body for changing the volume of the initial combustion chamber does not form the wall of the initial combustion chamber, so there is no need for heat resistance. It can be manufactured at low cost and there is no need to worry about it becoming stuck due to gunpowder residue produced during an explosion.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a partially cutaway front view showing the state at the time of driving, and FIG.
The figures also include: FIG. 3 is an enlarged sectional view showing the operating state of the return member; FIG. 4 is a perspective exploded view of the return member;
Fig. 5 is an enlarged cross-sectional view showing the state of connection between the cylinder and the gun barrel, and Figs. It is an explanatory diagram showing a usage state. 1...Fixing tool driving tool, 2...Housing, 3
... cylinder hole, 4 ... barrel, 7 ... chamber, 8 ... slot, 9 ... threaded part, 10 ... barrel, 11 ... piston member, 14 ... between, 16 ... tube Body, 17...
...Threaded portion, 18...Returning member.

Claims (1)

[Scope of utility model registration request] A housing 2 includes a gun barrel 4 having a piston member 11 fitted in a gun cavity 10 having a chamber 7 at the tail end, a slot 8 extending in the front-rear direction, and a threaded portion 9 on the outer peripheral surface of the tail end. It is fitted in the cylindrical hole 3 so as to be movable and rotatable in the longitudinal direction, and has a slot 15 that extends in the front-back direction and whose tail end is located forward of the tail end of the slot 8, and has a tail end portion. A cylindrical body 16 having a threaded portion 17 on its inner circumferential surface is inserted into the gap 14 between the housing 2 and the gun barrel 4 with the threaded portion 17 screwed into the threaded portion 9, and the tip thereof is inserted into the gap 14 between the housing 2 and the gun barrel 4. A position that penetrates through the slot 8 of the gun barrel 4 and protrudes into the gun cavity 10, and a position that is extracted from these and the cylindrical body 16.
A return member 18 is provided in the housing 2 at a position where it fits into the slot 15 of the cylinder body 16 when the gun barrel 4 is advanced; The fastener driving tool is characterized in that the piston member 11 has a piston 11a at its base end that is tightly fitted into the gun cavity 10 and engages with the return member 18 that projects into the gun cavity 10. .