JP2020025988A - Driving tool - Google Patents

Abstract

To lift a striking driver to a vertical movement end position to be a driving standby position without causing an increase in size and weight of the striking driver in a gas spring type driving tool which drives the striking driver with pressure of compressive gas generated by vertical movement of the striking driver.SOLUTION: A striking driver 13 is reduced in weight by holding the striking driver 13 between a lift roller 16 and a pressing roller 17, which are rotated by a lift motor 18, and vertically moving the striking driver by frictional force between both of the rollers.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a driving tool for driving a driving tool such as a nail.

  This type of driving tool includes a long impact driver in the main body for hitting the driving tool in the driving direction. Various types of power sources are used as power sources for moving the impact driver in the driving direction. A compressed air type driving tool that uses compressed air supplied from the outside as a power source with an air hose is generally used, but as a hoseless driving tool that does not require the connection of an air hose, a compressed gas is used as a driving source in the driving direction. A gas spring driven tool is provided. As disclosed in the following Patent Document 1, in a gas spring type driving tool, at the stage of returning the impact driver to the upper moving end position side by utilizing the engagement of the gear after impact, the gas sealed in the piston upper chamber is removed. A configuration is provided in which the drive source is used for impact by compression.

JP-A-2006-68221

  As described above, in the conventional gas spring type driving tool, it is necessary to provide a rack gear in the impact driver, and as a result, the rack gear is increased in size and weight is increased in order to secure the strength to withstand the gas compressive load. Since the impact driver becomes larger and heavier, there is a problem that the recoil at the time of driving becomes large and the driving tool becomes inconvenient.

  SUMMARY OF THE INVENTION It is an object of the present invention to improve the usability of a gas spring type driving tool by allowing the driver to be lifted to an upper end position corresponding to a driving standby position without increasing the size and weight of the driving driver.

  The above-mentioned problems are solved by the following inventions. A first invention is a driving tool which uses a gas pressure of a compressed gas generation chamber generated by moving a driving driver for driving a driving tool upward to an upper end position as a driving standby position as a power source of the driving operation. is there. In the first invention, a lift mechanism for moving the impact driver upward to the upper end position is provided. In the first aspect, the lift mechanism has a configuration in which the lift mechanism is moved upward by a frictional force generated by sandwiching the impact driver.

  According to the first invention, the lift mechanism for moving the impact driver upward to the upper moving end position has a configuration in which the impact driver is returned to the upper moving end position by frictional force, instead of the conventional meshing of the rack teeth. Therefore, the impact driver can be made smaller and lighter than in the prior art, the recoil at the time of impact can be suppressed, and the usability of the driving tool can be improved. In addition, durability and maintainability can be improved in that there is no chipping as in the related art.

  A second aspect of the present invention is the driving tool according to the first aspect, wherein the lift mechanism is configured to sandwich the impact driver by a spring force.

  According to the second aspect, the striking driver is sandwiched between the two members, and the member is pressed against the striking driver by a spring force (biasing force of a spring) to generate a frictional force.

  A third aspect of the present invention is the driving tool according to the second aspect, wherein the lift mechanism is configured to pinch and move the impact driver between a rotating lift roller and a pressing roller pressed by a spring force.

  According to the third aspect, the impact driver is sandwiched between the lift roller and the pressing roller, and the lift roller is rotated in the sandwiched state, whereby the impact driver is moved upward to the upper end position by frictional force.

  A fourth invention is the driving tool according to the third invention, wherein the impact driver is unevenly engaged with the peripheral surface of the lift roller.

  According to the fourth aspect, the frictional force for returning the impact driver to the upper end position can be efficiently increased.

  A fifth invention is a driving tool according to the fourth invention, in which the impact driver is pressed against two mutually facing inclined surfaces of a groove provided on a peripheral surface of the lift roller.

  According to the fifth aspect, the frictional force can be efficiently increased with a simple configuration.

  A sixth invention is the driving tool according to any one of the second to fifth inventions, wherein the spring force is adjustable.

  According to the sixth aspect, it is possible to easily set a necessary and sufficient frictional force for returning the impact driver to the upper end position.

1 is an overall side view of a gas spring type driving tool according to an embodiment of the present invention. This figure shows a state where the striking piston is located in the middle of the downward movement. FIG. 2 is a cross-sectional view taken along a line (II)-(II) in FIG. 1 and is a detailed view of a lift mechanism.

  Next, an embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, in this embodiment, a gas spring type DC nailing machine that uses a compressive force of a compressed gas G (a gas such as a nitrogen gas or an atmosphere) as an operation source is shown as the driving tool 1. The driving tool 1 includes a tool body 10, a driving nose portion 20 from which a driving tool n is driven, a handle portion 2 gripped by a user, and a connection driving tool N in which a number of driving tools n are temporarily connected in parallel. And a magazine 3 for loading.

  A striking cylinder 12 in which a striking piston 11 is hermetically sealed is provided in the tool body 10. A long rod-shaped impact driver 13 is coupled to the center of the lower surface of the impact piston 11. The striking driver 13 extends long downward (in the driving direction) from the center of the lower surface of the striking piston 11. The lower end of the driving driver 13 reaches the driving passage 20 b of the driving nose 20. One driving tool n is supplied into the driving passage 20b. When the driving driver 13 moves down in the driving passage 20b, the driving tool n is hit. The hitting tool n is hit from the tip end (the injection port 20a) of the driving path 20b and is driven into the driving material W.

  Above the impact cylinder 12 and in the upper chamber of the impact piston 11, there is provided a compressed gas generation chamber 14 which is formed in an airtight manner. Gas is sealed in the compressed gas generation chamber 14 in advance. When the striking piston 11 moves upward in the striking cylinder 12, the gas in the compressed gas generation chamber 14 is compressed, and the compressed gas G is generated. The generated compressed gas G serves as a power source (drive force) for moving the drive driver 13 downward to drive the drive tool n.

  A lower end damper 15 is provided below the impact cylinder 12 to absorb an impact when the impact piston 11 reaches the lower end. Below the lower moving end damper 15, a lift mechanism 6 for returning (moving upward) the impact driver 13 to the upper moving end position is provided. The lift mechanism 6 has a function as a compressed gas generating mechanism because the striking piston 11 is moved upward together with the striking driver 13.

  The lift mechanism 6 includes a lift roller 16 and a pressing roller 17 that sandwich the impact driver 13 from both left and right sides. FIG. 2 shows a state in which the impact driver 13 is sandwiched between the lift roller 16 and the pressing roller 17. The lift roller 16 is attached to an output shaft 18a of a lift motor 18 and is driven to rotate. The lift roller 16 is supported at both ends by two bearings 18b. The pressing roller 17 is pressed by the striking driver 13 by the spring force (biasing force) of the disc spring 19.

  The pressing roller 17 is rotatably supported by a pressing table 17b via a support shaft 17a. The pressing table 17b is supported on the base 17c so as to be displaceable in the vertical direction in FIG. 2 (the direction in which the pressing table 17b approaches and separates from the striking driver 13). A plurality of disc springs 19 are interposed between the base 17c and the pressing table 17b. Although two disc springs 19 are illustrated in the figure, the pressing force of the pressing roller 17 can be adjusted by changing the number of disc springs 19 or the like.

  The pressing table 17b is displaced upward in FIG. 2 by the retracting operation of the electromagnetic actuator 21. When the pressing table 17b is displaced upward, the pressing state of the pressing roller 17 against the impact driver 13 is released. The electromagnetic actuator 21 operates to the drawing side by supplying power. When the power supply to the electromagnetic actuator 21 is cut off, the retraction force is released, and the pressing table 17 b is displaced downward in FIG. 2 by the urging force of the disc spring 19, and is therefore pressed by the impact driver 13.

  As shown in FIG. 2, the impact driver 13 has an arc-shaped outer peripheral surface (arc surface 13a) almost half of its periphery and two flat outer surfaces (flat surface 13b) of the other half. On the other hand, a V-shaped groove is formed on the peripheral surface of the lift roller 16, and a pair of inclined surfaces (friction surfaces 16a) facing each other at a certain angle are provided. The flat surface 13b of the impact driver 13 is pressed against the two friction surfaces 16a in a line contact state. As a result, the pressing force of the disc spring 19 of the pressing roller 17 is dispersed in a direction different from the pressing direction and acts on the two friction surfaces 16a, so that a large frictional force can be efficiently obtained with a simple configuration. ing. Also, a high frictional force can be obtained by the impact driver 13 being fitted into a V-shaped groove provided on the peripheral surface of the lift roller 16 and pressed in a state of overlapping in a radial direction (concavo-convex engagement). It has become.

  A semicircular groove 17 d is formed on the peripheral surface of the pressing roller 17. The arc surface 13a is pressed against the groove 17d in a line contact state. As described above, by pressing the pair of friction surfaces 16 a of the lift roller 16 and pressing the semicircular groove 17 d of the pressing roller 17 against the striking driver 13, a large friction is applied to the striking driver 13. Force is generated.

  At the base of the handle part 2, a trigger-type switch lever 5 that is pulled by a fingertip of a grasped hand is provided. A rechargeable battery 4 is attached to the tip of the handle 2. A lift motor 18 for rotating the lift roller 16 uses the electric power of the battery 4 as a power source. The battery 4 can be used repeatedly by removing it from the tip of the handle portion 2 and charging it with a separately prepared charger.

  Although not shown, the driving nose portion 20 is provided with a contact arm that presses against the driving material W and relatively moves upward. When the contact arm is moved upward with the tip (injection port 20a) of the driving nose portion 20 toward the driving material W, or when one of the pulling operations (first operation) of the switch lever 5 is performed, a power supply state is set. The lift motor 18 starts. The activation of the lift motor 18 causes the lift roller 16 to rotate.

  When the lift roller 16 is rotated in a state where the lift roller 16 is sandwiched between the lift roller 16 and the press roller 17 generated when the press roller 17 is pressed by the strike driver 13, the strike driver 13 moves upward from the lower end position (initial state). Move up to the moving end position. The compressed gas G is generated in the compressed gas generation chamber 14 when the impact driver 13 is moved upward from the lower end position to the upper end position by the rotational power of the lift roller 16.

  In the state where the impact piston 11 is moved upward to the upper end position and the compressed gas G is generated in the compressed gas generation chamber 14, the other operation of the upward movement of the contact arm or the pulling operation of the switch lever 5 (the second operation) ), The electromagnetic actuator 21 is operated to the drawing side by energization, and the pressing state of the pressing roller 17 is released. When the pressing state of the pressing roller 17 is released, the striking piston 11 moves down due to the compressive force of the compressed gas G generated in the compressed gas generating chamber 14, so that the striking driver 13 moves down in the driving passage 20b. The driving tool n is hit.

  When the second operation is released after the impact piston 11 reaches the lower moving end and is driven, when the second operation is released, the retraction operation of the electromagnetic actuator 21 is released by shutting off the power supply, and the pressing roller 17 is again driven by the urging force of the disc spring 19 to drive the impact driver. 13 is pressed. The impact driver 13 moves upward due to frictional force between the lift roller 16 and the lift roller 16 generated by the pressing of the pressing roller 17.

  The magazine 3 is loaded with a connecting driving tool N in which a number of driving tools n are temporarily connected in parallel. The magazine 3 is supported straddling between the driving nose part 20 and the handle part 2. The magazine 3 is provided with a feed mechanism that feeds the connected driving tool N loaded at a pitch to the driving path 20b side in conjunction with the driving operation of the tool body 10.

  According to the driving tool 1 described above, the lift mechanism 6 for returning the impact driver 13 to the upper moving end position utilizes the frictional force generated by being sandwiched between the lift roller 16 and the pressing roller 17. 13 is returned to the upper end position. In this respect, it is significantly different from the conventional lift mechanism utilizing the engagement between the rack gear and the pinion gear.

  Since the impact driver 13 is moved upward by utilizing the frictional force, and it is not necessary to provide a rack gear in the impact driver 13 as in the related art, the impact driver 13 can be reduced in size and weight. By reducing the size and weight of the impact driver 13, the recoil at the time of impact can be reduced and the usability of the driving tool 1 can be enhanced.

  In addition, since the conventional gear meshing is not used, tooth chipping does not occur, and in this regard, the durability and maintainability of the lift mechanism 6 can be improved.

  Further, according to the lift mechanism 6 according to the present embodiment, a pair of friction surfaces 16a corresponding to the side surfaces of the V-shaped groove are provided on the peripheral surface of the lift roller 16, and the flat surfaces 13b are respectively provided on both the friction surfaces 16a. A large frictional force can be obtained by a wedge action by being pressed in a direction different from the pressing direction by the disc spring 19, and thereby a large lift force can be obtained.

  Various modifications can be made to the embodiment described above. For example, in the lift mechanism 6, the pressing force of the pressing roller 17 can be adjusted by changing the number of disc springs 19. Further, a configuration using other spring means such as a compression spring or a leaf spring instead of the disc spring 19 may be adopted. A configuration in which a pressing force is generated using an air damper or an electromagnetic actuator may be adopted.

  Also, the configuration in which one V-shaped groove is provided on the peripheral surface of the lift roller 16 has been illustrated. However, while a plurality of grooves are provided on the peripheral surface, a plurality of protrusions are provided on one surface of the flat-plate-shaped impact driver. Alternatively, a configuration may be employed in which each protrusion is fitted into a groove and generates a frictional force to move the protrusion upward.

  A protrusion may be provided on the peripheral surface of the lift roller, and the protrusion may be fitted into a V-shaped groove provided on the impact driver side to generate a frictional force therebetween.

  Although the configuration in which the impact driver 13 is sandwiched by one set of the lift roller 16 and the pressing roller 17 is illustrated, a configuration in which the impact driver 13 is sandwiched by a plurality of sets may be employed.

1 ... Punching tool (gas spring type)
Reference numeral 2 Handle part 3 Magazine 4 Battery 5 Switch lever 6 Lift mechanism 10 Tool body 11 Impact piston 12 Impact cylinder 13 Impact driver 13 a Arc surface, 13 b Flat surface 14 Compressed gas generation chamber 15 Lower moving end damper 16 Lift roller 16a Friction surface 17 Press roller 17a Support shaft, 17b Press table, 17c Base portion, 17d Groove portion 18 Lift motor 18a Output shaft, 18b Bearing 19 Disc spring 20: driving nose portion 20a: injection port, 20b: driving passage

Claims (6)

A driving tool that uses a gas pressure of a compressed gas generation chamber generated by moving a driving driver for driving a driving tool upward to an upper moving end position as a power source of the driving operation,
A lift mechanism for moving the impact driver up to the upper moving end position is provided.
A driving tool, wherein the lift mechanism is configured to move upward by a frictional force generated by sandwiching the impact driver. The driving tool according to claim 1,
A driving tool, wherein the lift mechanism is configured to sandwich the impact driver by a spring force. The driving tool according to claim 2,
A driving tool in which the lift mechanism is configured to be sandwiched between a lift roller rotating the impact driver and a pressing roller pressed by the spring force and moved upward.   4. The driving tool according to claim 3, wherein the driving driver is unevenly engaged with a peripheral surface of the lift roller.   The driving tool according to claim 4, wherein the driving driver is pressed against two mutually facing inclined surfaces of a groove provided on a peripheral surface of the lift roller.   The driving tool according to any one of claims 2 to 5, wherein the spring force is adjustable.

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