JPH0551574U - Driving device for feeding fasteners - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention relates to a driving tool for driving a stopper by using compressed air as a power source, so that when the pressure of the power source fluctuates, a plurality of fasteners cannot be sent into the injection port. Is to [Structure] The switch 2 and the feed piston rear chamber 34 are communicated with each other, and the normal feed piston 13 is located at a position where the stopper 9 is fed to the injection port. Further, the return air chamber 29 and the feed piston front chamber 35 are communicated with each other, and the feed piston 1
3 is in the retracted position.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a fastener feeding device for a driving tool that drives fasteners such as nails by using compressed air as a power source.

[0002]

[Prior Art]

 FIG. 7 shows a part of the fastener feeding device of the driving tool of Japanese Utility Model Laid-Open No. 02-130773 previously filed by the present applicant. The trigger 12, the switch 2 operated by the operation of the trigger 12, the feed claw 8 for feeding the stop coupling band 27 connecting the stop 9 to the ejection port 23, the feed piston 13 for moving the feed claw 8 forward and backward, and the like. The feed piston rear chamber 34 and the passage 24 through which compressed air for opening and closing the main valve 16 to be described later passes through the pressurized gas supply passages 20 and 21. A feed valve 3 for operating the feed piston 13 is provided between the pressurized gas supply passages 20 and 21. The feed valve 3 is characterized in that the feed of the stopper 9 can be automatically or manually switched depending on whether or not the operator 40 is fixed in the open state. Normally, as shown in FIG. 7, since compressed air is flowing into the rear chamber 34 of the feed piston, the feed piston 13 moves forward, that is, to the left in the figure, and the stopper 9 is fed to the injection port 23 by the feed pawl 8. It is in a state of being When the operator 40 is automatically operated to drive the fastener or the operator 40 is manually operated, the compressed air in the rear chamber 34 of the feed piston is exhausted, and the feed spring 11 moves the feed piston 13 backward. Moving. Then, the window 37 next to the fastener coupling band 27 and the feed claw 8 come into engagement with each other.

[0003]

[Problems to be solved by the device]

 In the driving machine equipped with the stopper feeding device shown in FIG. 7, when the source pressure hose is repeatedly attached and detached, the pressure in the feed piston rear chamber 34 communicating with the driving air chamber 33 fluctuates. In response to this, the feed spring 11 operates the feed piston 13 to feed a plurality of stoppers 9 into the injection port 23. Also, when the operator 40 is operated a plurality of times, the pressure in the rear chamber 34 of the feed piston fluctuates, and a similar phenomenon occurs. The object of the present invention is to overcome the above-mentioned drawbacks of the prior art.

[0004]

[Means for Solving the Problems]

 The above object is achieved by connecting the return air chamber, which stores compressed air for returning the stopper striking piston to the initial position, with the feed piston front chamber, and by eliminating the feed spring.

[0005]

[Action]

 With the stopper feeding device configured as described above, even if the pressure in the rear chamber of the feed piston fluctuates due to the attachment / detachment of the source pressure hose or the operation of the operating element, the feed piston does not move due to the absence of the feed spring. It does not happen, and multiple stops are not sent into the injection port. When the switch is operated and the stopper is hit, the pressure in the rear chamber of the feed piston is atmospheric pressure, and the pressure in the front chamber of the feed piston in communication with the return air chamber is the same as the pressure in the driving air chamber or repeated atmospheric pressure. Therefore, the feed piston 13 maintains the retracted state. When the switch is turned off, the hitting of the stopper is completed, the pressure in the front chamber of the feed piston becomes atmospheric pressure, and the pressure in the rear chamber of the feed piston becomes the pressure of the driving air chamber.Therefore, the feed piston advances and the next stopper in the discharge port. Will be sent to.

[0006]

【Example】

 The present invention will be described below with reference to the accompanying drawings. 1 to 6, a cylindrical cylinder 5 is provided in the driving machine body 1, and a piston 6 is held in the cylinder 5 so as to be vertically movable. A piston ring 28 is provided on the outer circumference of the piston 6 to seal between the cylinder 5 and the piston 6. A main valve 16 is provided at the upper end of the cylinder 5, and when the main valve 16 rises, the upper end of the cylinder 5 is opened and the exhaust valve 4 is closed, and the driving air chamber 33 and the piston upper chamber 30 communicate with each other. The lower end of the cylinder 5 closes, the exhaust valve 4 opens, and the piston upper chamber 30 communicates with the atmosphere. The main valve chamber 31 communicates with the switch 2 via the repetitive valve 17 and the passage 24, and also communicates with the driving air chamber 33 via the passage 26. A lower piston chamber 29 including a return air chamber 19 is provided below the cylinder 5, and the return air chamber 19 communicates with a repetitive valve chamber 32 via a passage 25. A communication passage 18 is provided on a side wall of the cylinder 5 via a check valve 22 so that the piston upper chamber 30 and the piston lower chamber 29 communicate with each other after the piston 6 has passed. The communication passage 18 is provided to prevent jumping up of the driving tool body 1 that occurs when the stopper 9 is no longer driven due to insufficient driving energy in the course of driving the stopper 9. The position of the communication passage 18 is such that the compressed air in the piston upper chamber 30 flows into the piston lower chamber 29 from the communication passage 18 via the return air chamber 19 before the stop 9 of the stopper 9 Is set to be substantially the same as or higher than the pressure in the piston upper chamber 30.

FIG. 2 shows a cross-sectional view (feeding portion 15) of the BB line of FIG. 1 and the feed valve 3, and one end of the injection port 23 through which the stopper 9 is ejected is connected by a stopper connecting band 27. A stop guide path 39 for guiding the connecting stop 10 is provided. A part of the stopper guide path 39 is exposed inside the stopper guide path 39 and engages with the window 37 of the stopper connecting band 27 to feed the stopper 10. The feed piston 13 having the feed claw 8 The feed piston 13 is moved forward by the compressed air supplied from the pressurized gas supply passage 21 to the feed piston rear chamber 34, and compressed to the feed piston front chamber 35 from the pressurized gas supply passage 7. It returns to the rear by being supplied with air. The stopper guide path 39 has a check claw 43 that engages with the window 37 of the stopper connecting band 27 and locks the rearward movement of the stopper connecting band 27.

Next, the operation of the driving tool adopting the device of the present invention will be described. In FIGS. 3 and 4, when the trigger 12 is operated, the switch 2 is opened, the compressed air in the main valve chamber 31 is exhausted through the passage 24 and the switch 2, and the main valve 16 rises. As the main valve 16 rises, the exhaust valve 4 closes, the piston upper chamber 30 communicates with the driving air chamber 33, the compressed air in the driving air chamber 33 flows into the piston upper chamber 30, and the piston 6 descends. To do. At this point, the energy of the compressed air is transmitted to the piston 6 as the kinetic energy of the piston 6. When the piston 6 passes through the communication passage 18, the compressed air in the piston upper chamber 30 flows into the piston lower chamber 29 from the communication passage 18, and the pressure in the piston lower chamber 29 rapidly rises. Further, the compressed air flows into the feed piston front chamber 35 from the pressurized gas supply passage 7, and the feed piston 13 moves rearward as shown in FIG. When the feed piston 13 moves rearward, the feed pawl 8 also moves rearward, and the feed pawl 8 engages the window 37 of the stopper coupling band 27 to feed the next stopper 9.

On the other hand, since the repetitive valve chamber 32 communicates with the piston lower chamber 29 via the passage 25, the repetitive valve 17 descends due to the pressure increase in the piston lower chamber 29, and the passage 24 is closed. Therefore, the pressure in the main valve chamber 31 rises due to the compressed air flowing in from the passage 26, and the main valve 16 descends. When the main valve 16 is lowered, the upper end of the cylinder 5 is closed and the exhaust valve 4 is opened, so that the compressed air in the piston upper chamber 30 is exhausted from the exhaust valve 4. Therefore, as shown in FIG. 5, the piston 6 is pushed up by the compressed air in the piston lower chamber 29 and returns to the top dead center. As the piston 6 returns, the pressure in the piston lower chamber 29 expands and becomes lower, and is further exhausted from the gap between the piston 6 and the injection port 23, so that the pressure becomes even lower. Therefore, as shown in FIG. 6, the compressed air in the feed piston front chamber 35 is also exhausted. The feed piston front chamber 35 and the feed piston rear chamber 34 both become atmospheric pressure, and the feed piston 13 maintains the state of moving rearward. Further, since the pressure in the repetitive valve chamber 32 also decreases, the repetitive valve 17 is pushed up by the pressure in the main valve chamber 31, the passage 24 opens, and the compressed air in the main valve chamber 31 is exhausted from the switch 2. When the compressed air in the main valve chamber 31 is exhausted, the main valve 16 rises again and the driving operation is performed. The above-described operation is repeated and the stopper 9 is driven into the material to be driven.

Next, as shown in FIG. 6, when the trigger 12 is released and the switch 2 is closed, the compressed air in the driving air chamber 33 flows into the main valve chamber 31 through the passage 24, so that the main valve 16 Is lowered and the repetition of the driving operation is stopped at this point. When the operator 40 operates the operator 40 automatically or manually, the compressed air in the driving air chamber 33 is sent through the passage 24 and the pressurized gas supply passages 20 and 21 to the feed piston rear chamber 34. Flow into. As a result, the feed piston 13 and the feed pawl 8 move forward, the stopper coupling band 27 engaged with the feed pawl 8 also moves forward, and the next stopper 9 is fed into the injection port 23.

Therefore, when the source pressure hose is repeatedly attached and detached, the pressure in the feed piston rear chamber 34 communicating with the driving air chamber 33 also fluctuates, but the pressure in the feed piston front chamber 35 is atmospheric pressure, so 13 maintains the front position as shown in FIG. Therefore, it is not necessary to feed a plurality of stoppers 9 into the ejection port 23. Further, even if the operator 40 is operated a plurality of times, the plurality of stoppers 9 will not be fed into the ejection port 23 as in the above.

[0012]

[Effect of the device]

 As described above, according to the present invention, since the feed spring for retracting the feed piston is removed and the return air chamber and the feed piston front chamber are communicated with each other, the driving air can be repeatedly attached and detached. Even if the pressure in the chamber changes, the feed piston does not move and multiple stops are not fed into the injection port. Further, even if the operator is operated a plurality of times, a plurality of fasteners will not be sent similarly. Therefore, the driving machine can be used stably for a long period of time.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a fastener supplying device for a driving tool according to the present invention.

FIG. 2 is a cross-sectional view showing the relationship between the cross section taken along the line BB of FIG. 1 and the feed valve.

FIG. 3 is a cross-sectional view showing the operating state of FIG.

4 is a sectional view corresponding to FIG. 2 showing the operation state of FIG.

5 is a cross-sectional view showing the operating state of FIG.

6 is a sectional view corresponding to FIG. 2 showing the operating state of FIG.

FIG. 7 is a sectional view corresponding to FIG. 2 showing an example of a conventional device.

[Explanation of symbols]

1 is a driver main body, 2 is a switch, 5 is a cylinder, 6 is a piston, 9 is a stopper, 13 is a feed piston, 14 is a control valve, 19 is a return air chamber, 34 is a feed piston rear chamber, 3
5 is a front chamber of the feed piston.

Claims (1)

[Scope of utility model registration request] 1. A piston which is held in a cylinder so as to be movable up and down and whose lower end strikes a stopper in an injection port to drive it, and a piston which is provided at a position operable from the outside and drives the piston on the upper surface of the piston. A control valve that supplies compressed air, a return air chamber that stores compressed air that returns the piston to the initial position, and a feed pawl that feeds a coupling stopper are attached to the tip, and the feed piston rear chamber when the piston is driven. In a driving machine equipped with a feed piston that moves forward by compressed air supplied to feed the stopper, a feed piston front chamber to which compressed air for moving the feed piston is fed is referred to as the return air chamber. A fastener feeding device for a driving machine characterized by being communicated with each other.