CN213889863U - Driving tool - Google Patents

Abstract

In a mechanical spring type driving tool for impacting a driven member by an urging force of an impact spring, in a reaction absorbing mechanism for absorbing a reaction during driving, an elastic member for impact of a retreating end of a counterweight is attached to the counterweight, and therefore, it is difficult to improve durability thereof. In the present invention, the object is to improve the durability of the elastic member in the reaction absorbing mechanism. An elastic member (54) for absorbing an impact at the retreat end position of the counterweight (51) is mounted on the guide housing (52) side, not on the counterweight (51) side. This facilitates the enlargement and solid-state formation of the elastic member (54), and also improves the degree of freedom of mounting and durability thereof.

Description

Driving tool

Technical Field

The present invention relates to a mechanical spring type driving tool, such as a rechargeable nail gun, which utilizes the acting force of a compression spring as the driving force.

Background

The nail gun is mainly used for the combination of wood and gypsum boards. The compressed air driven nail gun has a compressed air driven cylinder, and uses thrust generated by the cylinder as driving force. The mechanical spring type nail gun has an impact spring (compression spring), and utilizes the urging force of the impact spring as a driving force.

The mechanical spring type driving tool disclosed in patent document 1 includes a reaction absorbing mechanism that absorbs a reaction at the time of driving with the advance of the impact driver. The reaction absorbing mechanism includes a weight that moves in a direction opposite to the impact driver, and a weight spring that biases the weight in a direction opposite to the driving direction. When the impact driver impacts, the counterweight moves in the opposite direction to the driving direction, and the tail end of the counterweight collides with the stopper. This makes it possible to cancel the reaction of the impact driver by the counterweight and reduce the reaction of the impact. An elastic component is arranged at the tail end of the counterweight. Therefore, the impact at the time of collision with the stopper of the counterweight is alleviated by the elastic member.

Patent document 1: japanese patent laid-open publication No. 2017-87414

However, the elastic member is cylindrical for mounting on the distal end portion of the counterweight. Therefore, it is difficult to increase the volume of the elastic member for improving durability. Therefore, a configuration capable of improving the durability of the elastic member of the reaction absorbing mechanism has been conventionally required.

SUMMERY OF THE UTILITY MODEL

According to a feature of the utility model, squeeze into the instrument and have: an impact driver that impacts the drive member; and an impact spring for urging the impact driver in the driving direction. The driving tool also has a weight, a guide case, and an elastic member. The counterweight moves in the reverse direction of the driving direction in synchronization with the movement of the impact driver in the driving direction in order to absorb the reaction of the impact driver during the driving. The guide shell accommodates the counterweight inside and guides the movement of the counterweight. The elastic member is supported by the guide case so as to receive an impact from the weight at a moving end in a direction opposite to the driving direction of the weight.

Thus, the resilient member is supported by the guide shell side rather than the counterweight side. Therefore, the elastic member does not need to be cylindrical to be attached to the end of the counterweight, and various shapes can be adopted. This can increase the volume of the elastic member or can provide a shape that can easily absorb an impact. As a result, the durability of the elastic member can be improved. Further, since the elastic member is not attached to the weight, the shape of the weight can be simplified, and the manufacturing cost thereof can be reduced.

The elastic member may be directly attached to the guide housing or indirectly attached to the guide housing. For example, the elastic member may be attached to the guide housing via a frame or the like that supports the guide housing. The elastic member can have, for example, a solid cylindrical shape, a prismatic shape, a conical shape, and a cylindrical shape. The elastic member may be attached to the main body case by screwing, bonding, or sandwiching.

According to the utility model discloses an other characteristics, the limiting plate of the reverse direction of the direction of squeezing into of restriction counter weight sets up in main part casing. The elastic component is positioned by the limiting plate and the guide shell. Therefore, the elastic member is positioned using the stopper plate and the guide shell. Thereby, the elastic member is stably positioned in the main body case.

According to other features of the utility model, the elastomeric element has the flange portion that sets up between the tip of limiting plate and direction shell. Therefore, the flange facilitates positioning of the elastic member.

According to another feature of the present invention, there is provided a spring for a weight for applying a force to the weight in a direction opposite to the driving direction. The counterweight spring is accommodated in the guide housing. Therefore, the guide housing plays a role of guiding the movement of the counterweight and a role of the spring for supporting the counterweight.

According to other features of the present invention, the spring for the counterweight has no backup ring at both ends. Therefore, stress concentration on the backup ring is avoided and durability of the spring for the counterweight is improved.

According to other features of the invention, the resilient member has a tapered distal end portion that tapers toward the counterweight. Therefore, the elastic member can be easily deformed.

According to other features of the invention, the resilient member is solid. Therefore, the volume of the elastic member can be increased, and the durability of the elastic member can be improved.

According to the utility model discloses a according to other characteristics, squeeze into the instrument and have the direction shell in one side of impact actuator, have the second direction shell at the opposite side, have the second counter weight, this second counter weight is acceptd in the second direction shell, and with impact actuator to squeeze into the removal of direction in step to squeeze into the direction and remove in the opposite direction. Therefore, the movement operation of the two weights can be performed with good balance on both sides of the impact driver.

According to other features of the utility model, have the limiting plate that extends along the tip of direction shell and the tip of second direction shell. The limiting plate limits the movement of the counter weight in the opposite driving direction through the elastic component, and the second elastic component is fastened to limit the movement of the second counter weight in the opposite driving direction. Therefore, since the stopper plate is a single member, the operability as the member and the assemblability of the pair of left and right elastic members can be improved.

Drawings

Fig. 1 is an overall side view of a driving tool. This figure shows a state in which the right side half casing is removed to expose the inside.

Fig. 2 is a cross-sectional view taken along line (II) - (II) in fig. 1, and is a transverse cross-sectional view of the tool body portion.

Fig. 3 is a sectional view taken along the line (III) to (III) in fig. 1, and is a longitudinal sectional view in the left-right width direction of the tool main body.

Fig. 4 is a longitudinal sectional view of the tool body in the longitudinal direction.

Fig. 5 is a top view of the actuator return mechanism. This figure shows the state before the impact driver returns to the retracted end position after reaching the advanced end position.

Fig. 6 is a side view of the driving portion and the reaction absorbing mechanism.

Fig. 7 is a perspective view of the left and right reaction absorbing mechanisms as viewed obliquely from below.

Fig. 8 is a perspective view of the vicinity of the left and right elastic members.

Fig. 9 is an enlarged exploded view of part (IX) of fig. 6, and is a sectional view showing an assembling process of the elastic member.

Description of the reference numerals

W. driven into a material; a driving tool (a charging type nail gun); driving into a nose part; an impact driver; a coupling pin; an ejection port; a retreat end sensor; a tool body portion; a body housing; a motor receiving portion; an electric motor; a planetary gear train; an output gear; a motor axis; a handle portion; a switch lever; a switch body; a nail cartridge; a power supply portion; a battery mounting portion; a battery pack; a controller; a drive return mechanism; an idle gear (idler gear); a fulcrum; a return gear; a fulcrum; a mechanism base; a first engaging portion; a second engaging portion; a first snap receiving portion; a second engagement receiving portion; an impact mechanism; a driver mount portion; a cylinder support; an impact spring; a fulcrum portion; an elastic member; 45.. a retaining sleeve; a mechanism frame; a reaction absorbing mechanism; a counterweight (second counterweight); a guide shaft portion; a guide housing (second guide housing); a front wall portion, 52b. 53.. a spring for the counterweight; an end portion; an elastic member (second elastic member); a terminal portion; a base; a flange portion; a driven side rack and pinion; 56.. drive a side rack gear; a pinion gear; a fulcrum; 58..

Detailed Description

Next, an embodiment of the present invention will be described with reference to fig. 1 to 9. As shown in fig. 1, in the present embodiment, a mechanical spring type nail gun using the biasing force of a compression coil spring as the impact force (driving force) is exemplified as the driving tool 1. The driving tool 1 illustrated has a rechargeable battery pack 22 as a power source.

The driving tool 1 includes: a tool body portion 10; a motor housing portion 12 in which an electric motor 13 as a drive source is housed; a grip portion 16 to be held by a user; a nail barrel 19 for loading a plurality of driven members; and a power supply section 20. The tool body 10 has a structure in which an actuator return mechanism 30, an impact mechanism 40, and a reaction absorbing mechanism 50 are built in a body case 11. In the following description, the driving direction of the driven material is defined as the front side, the reverse driving direction is defined as the rear side, and the left-right direction is defined as the reference of the user.

A driver head 2 for guiding the impact driver 3 in a driving direction is provided at a front portion of the tool body 10. The impact driver 3 for impact of the driver is advanced in the driving path of the driver head 2, thereby impacting the driver and driving it out of the injection hole 4 at the distal end thereof. One driving material W is driven into the workpiece W from the injection hole 4.

The motor housing portion 12 and the grip portion 16 extend downward from a lower portion of the tool body 10. The motor housing portion 12 is on the front side, and the grip portion 16 extends substantially parallel to each other on the rear side. An electric motor 13 as a drive source of the actuator return mechanism 30 is housed in the front motor housing portion 12. As shown in fig. 1, the motor axis M of the electric motor 13 extends in the vertical direction in a direction intersecting (orthogonal to) the driving direction (front-rear direction).

The cartridge 19 is coupled to the driver head 2. The nail barrel 19 extends long downward from the lower surface of the driver head 2 along the front side of the motor housing portion 12. The nail barrel 19 can be filled with a plate-shaped connecting driving piece which temporarily fixes a plurality of driving pieces in parallel with each other. The loaded connecting fastener is fed to the driver head 2 in pitch in conjunction with the driving operation of the tool body 10. Thereby feeding the driven members into the driving path one by one.

A space for a user to insert one finger is provided between the motor housing portion 12 on the front side and the grip portion 16 on the rear side. The grip portion 16 can be gripped by fingers inserted into the space. A switch lever 17 of a trigger type is provided on an upper portion of the grip portion 16. A switch main body 18 is built in the rear of the switch lever 17. By the pulling operation of the switch lever 17, the switch main body 18 is turned on to start the electric motor 13.

A power supply unit 20 is provided between the motor housing unit 12 and the distal end of the handle unit 16. The power supply unit 20 has a battery mounting portion 21 on the lower surface side. One battery pack 22 can be mounted on the battery mounting portion 21. The electric power of the battery pack 22 is mainly supplied as a power source of the electric motor 13.

The battery pack 22 can be repeatedly used by being removed from the battery mounting portion 21 and charged by a separately prepared charger. The battery pack 22 is also applicable to a battery pack having high versatility and usable as a power source for other electric tools such as a rechargeable screw fastener and a cutting tool. A control circuit board for controlling the operation of the electric motor 13 and a controller 23 having a power supply circuit board built therein are housed in the battery mounting portion 21.

As shown in fig. 4, the impact mechanism 40 includes: an actuator mount portion 41 that supports the impact actuator 3; a mechanism frame 46 that supports the actuator base 41 so as to be movable forward and backward; and an impact spring 42 that biases the driver seat portion 41 in the driving direction. A compression coil spring, in which a so-called spider is omitted, is applied to the impact spring 42. The rear portion of the impact driver 3 is coupled to the upper portion of the driver mount portion 41 via a coupling pin 3a. The impact driver 3 is an elongated plate material and advances and retreats in a driving passage of the driver head 2.

The actuator base portion 41 integrally has a cylindrical support portion 41a extending in the front-rear direction. On the other hand, the mechanism frame 46 has a spindle portion 43 of a round bar shape. The spindle portion 43 extends across substantially the entire length from the front to the rear of the mechanism frame 46. The front and rear portions of the spindle portion 43 are coupled to the mechanism frame 46 so as not to be axially and axially displaceable, respectively. An impact spring 42 is mounted around the fulcrum portion 43.

A spindle portion 43 is inserted through the inner circumferential side of the cylindrical support portion 41a without wobbling in the radial direction. Thus, the actuator base portion 41 is supported to be slidable in the front-rear direction with respect to the mechanism frame 46. Further, the actuator mount portion 41 restricts displacement of the spindle portion 43 about the axis. An impact spring 42 is installed between the driver seat portion 41 and the rear portion of the mechanism frame 46. The impact spring 42 biases the driver seat portion 41 and the impact driver 3 in the driving direction. By the urging force of the impact spring 42, a single driven material is struck by the impact driver 3 and is ejected from the ejection port 4.

At the front portion of the mechanism frame 46, there is an elastic member 44 for absorbing an impact at the forward end position of the driver mount portion 41. The elastic member 44 has a cylindrical shape and is disposed on the outer peripheral side of the spindle portion 43. Further, a cylindrical holding sleeve 45 is provided at the rear of the mechanism frame 46. The retaining sleeve 45 is disposed on the rear inner circumferential side of the impact spring 42. Buckling, deformation, and the like at the time of contraction of the impact spring 42 are avoided by the holding sleeve 45.

The impact actuator 3 is returned to the retreat end position by an actuator return mechanism 30 having the electric motor 13 as a drive source. As shown in fig. 1, 4, and 5, the rotational output of the electric motor 13 is reduced in speed by the planetary gear train 14 and output to the output gear 15. The output gear 15 meshes with an idle gear 31 (idle gear having no speed increasing and decreasing function).

The idle gear 31 meshes with the return gear 32. The idle gear 31 is supported by the mechanism base 33 via a support shaft 31a. The return gear 32 is supported by the mechanism base 33 via a support shaft 32a. The mechanism base 33 is a thin plate-shaped pedestal portion extending in the front-rear direction, and is fixed along the lower side of the mechanism frame 46.

Since the return gear 32 and the output gear 15 are engaged with one idle gear 31, the rotation direction of the return gear 32 coincides with the output gear 15. The direction of rotation of return gear 32 is counterclockwise as indicated by the filled arrow in fig. 5.

As shown in fig. 5 and 6, a first engaging portion 34 and a second engaging portion 35 are provided on the upper surface of the return gear 32. The first engaging portion 34 and the second engaging portion 35 are cylindrical protruding portions having substantially the same diameter and are provided in a state of protruding upward. The amount of upward projection of the first engaging portion 34 is small, and is approximately half of the second engaging portion 35.

As shown in fig. 5, the first engaging portion 34 and the second engaging portion 35 are arranged at positions eccentric by substantially the same distance from the rotation center of the return gear 32. The first engaging portion 34 is disposed on the front side in the rotational direction rotated by approximately 100 ° in the rotational direction with respect to the second engaging portion 35.

As shown in fig. 4 and 7, the actuator base portion 41 has a first engagement receiving portion 36 and a second engagement receiving portion 37 integrally formed on the lower surface thereof so as to correspond to the first engagement portion 34 and the second engagement portion 35. The first engagement receiving portion 36 is disposed on the rear side, and the second engagement receiving portion 37 is disposed on the front side of the first engagement receiving portion 36 by a predetermined distance.

The first engagement receiving portion 36 and the second engagement receiving portion 37 each protrude downward from the lower surface of the actuator base portion 41. The amount of downward projection of the rear first engagement receiving portion 36 is greater than the amount of downward projection of the front second engagement receiving portion 37. The first engagement receiving portion 36 projects downward more largely so as to engage with the lower first engagement portion 34, while the second engagement receiving portion 37 projects downward by a projection amount sufficient to engage with the higher second engagement portion 35. In the entire process of the displacement of the impact driver 3 in the driving direction and the return operation in the reverse direction to the driving direction, only the first engaging portion 34 is engaged with the first engaging receiving portion 36 on the rear side, and only the second engaging portion 35 is engaged with the second engaging receiving portion 37 on the front side.

The return gear 32 rotates once to perform a series of return operations of the impact driver 3. In a series of returning operations, a first stage of engagement of the first engagement portion 34 with the first engagement receiving portion 36 and a second stage of engagement of the second engagement portion 35 with the second engagement receiving portion 37 are successively completed. Thereby, the driver mount portion 41 and the impact driver 3 return from the forward end position to the backward end position against the urging force of the impact spring 42.

Fig. 5 shows a state immediately after the driver return mechanism 30 is activated in an initial state (non-operating state) where the driver 3 is impacted to the forward end position by the urging force of the impact spring 42. The activation of the actuator return mechanism 30 is started by turning on the switch main body 18 by a pushing operation of the switch lever 17. When the switch main body 18 is turned on, the electric power supply to the electric motor 13 is started, and the electric motor 13 is started.

When the electric motor 13 is started, the return gear 32 starts rotating in the counterclockwise direction in fig. 5. The return gear 32 rotates, and the first engagement portion 34 is pressed against the front surface of the first engagement receiving portion 36. The driver seat portion 41 is pressed rearward against the urging force of the impact spring 42 by displacing the first engaging portion 34 rearward by the counterclockwise rotation of the return gear 32 while keeping the state of pressing the first engaging receiving portion 36. By pressing the driver mount portion 41 rearward, the impact driver 3 returns from the forward end position toward the rearward end position. In a first stage in which the first engaging portion 34 engages with the first engagement receiving portion 36 and the impact actuator 3 is returned, the second engaging portion 35 gradually approaches the second engagement receiving portion 37.

Then, the return gear 32 rotates counterclockwise, whereby the return motion shifts from the first stage to the second stage. In the second stage, the first engaging portion 34 is separated from the front surface of the first engaging receiving portion 36, and the second engaging portion 35 is pressed against the front surface of the second engaging receiving portion 37. In the second stage, the power transmission path for the return operation by the rotation of the return gear 32 is transmitted from the first engagement portion 34 to the second engagement portion 35. In the second stage of the return operation, the second engagement portion 35 is displaced rearward, whereby the actuator base portion 41 continues to return toward the retreat end position against the urging force of the impact spring 42.

In fig. 5, the first engagement receiving portion 36 and the second engagement receiving portion 37 at the stage when the second engagement portion 35 reaches the retreat end and the actuator base portion 41 returns to the retreat end position are shown by two-dot chain lines. At this stage, the actuator base portion 41 and the impact actuator 3 return to the retracted end position.

Immediately after the impact actuator 3 returns to the retreat end position, the return gear 32 further rotates, and the second engagement portion 35 is disengaged from the second engagement receiving portion 37. Thereby, the power for returning the actuator base portion 41 to the retreating end position side against the urging force of the impact spring 42 is cut off. Thereby, the driver mount portion 41 moves forward by the biasing force of the impact spring 42, and is driven by the impact driver 3.

As shown in fig. 5, when the actuator base portion 41 reaches the retreat end position, the retreat end sensor 7 is turned on by the first engagement receiving portion 36. Thereby, the electric power supply to the electric motor 13 is cut off substantially simultaneously with the driving operation, and the electric motor 13 is stopped. By stopping the electric motor 13, the displacement of the first engagement portion 34 and the second engagement portion 35 is stopped, and the actuator return mechanism 30 is stopped. In the impact mechanism 40, the driver base portion 41 is returned to the initial position at which it reaches the advance end.

The reaction at the time of impact and at the time of impact accompanying the forward movement of the impact driver 3 is absorbed by the reaction absorbing mechanism 50. As shown in fig. 7, the reaction absorbing mechanisms 50 are arranged in pairs on both sides of the impact mechanism 40 in the direction orthogonal to the driving direction. The left and right reaction absorbing mechanisms 50 have a common structure, and each has a weight 51. The weights 51 on the left and right sides move in the direction opposite to the driving direction (in the direction opposite to the driving direction) to cancel the reaction at the time of driving. Further, by disposing the reaction absorbing mechanisms 50 in a left-right pair with respect to the impact actuator 3, the moving operation of the counterweight 51 is well balanced in the left-right direction.

The reaction absorbing mechanism 50 includes a weight 51, a guide case 52, a weight spring 53, a stopper plate 58, and an elastic member 54. In synchronization with the movement of the impact driver 3 in the driving direction, the weight 51 moves in the opposite direction to the driving direction. The weight 51 is accommodated inside the guide case 52 and guided in the driving direction and the reverse direction of the driving direction. The weight 51 is biased in the reverse direction of the driving direction by a weight spring 53. The weight spring 53 is housed inside the guide housing 52. The position of the moving end of the counterweight 51 in the direction opposite to the driving direction is restricted by the restricting plate 58. The impact at the moving end position of the weight 51 in the opposite direction to the driving direction is absorbed by the elastic member 54 which is an elastic body.

The weight 51 has a cylindrical shape. The counterweight 51 integrally has a small-diameter guide shaft portion 51a extending coaxially and forward. The counterweight spring 53 is attached in a state where the guide shaft portion 51a is inserted through the inner peripheral side. The counterweight-use spring 53 is mounted between the front surface of the counterweight 51 and the front wall portion 52a of the guide housing 52.

As shown in fig. 6, a so-called spider (a winding portion having no spring action) is omitted from an end portion 53a of the counterweight spring 53. Therefore, the end 53a of the counterweight spring 53 abuts on the front surface of the counterweight 51 and the front wall 52a of the guide housing 52 in a point contact state.

The weight 51 and the weight spring 53 are housed in the guide case 52. The guide housing 52 has both a function of guiding the movement of the counterweight 51 and a function of supporting the counterweight spring 53. The guide housing 52 has a long tube shape from the front to the rear of the impact mechanism 40. Inside the guide housing 52, the weight 51 moves forward and backward. The guide case 52 has a slit 52b at an upper portion thereof. The slit 52b is formed over the entire region in the longitudinal direction of the case 52. The driven-side rack gear 55 engages with the counterweight 51 through the slit 52b. The meshing teeth of the driven-side rack gear 55 face upward.

A driving side rack gear 56 is provided above and opposite to the driven side rack gear 55. The drive-side rack gear 56 is integrally coupled to the driver mount portion 41 of the impact mechanism 40. The meshing teeth of the drive-side rack gear 56 face downward. One pinion gear 57 is disposed between the driving side rack gear 56 and the driven side rack gear 55. The pinion gear 57 is rotatably supported by the mechanism frame 46 via a support shaft 57a. The pinion gear 57 is always engaged with the upper driving side rack gear 56 and the lower driven side rack gear 55.

Therefore, the moving direction of the driven side rack gear 55 is always opposite to the driving side rack gear 56. Thereby, the counterweight 51 always moves in synchronization with the driver base portion 41 and the impact driver 3 to the opposite side. In the stage where the impact driver 3 is returned in the reverse direction of the driving direction by the driver return mechanism 30, the weight 51 is moved in the driving direction against the weight spring 53. In a stage where the impact driver 3 moves in the driving direction by the biasing force of the impact spring 42, the weight 51 is returned in the reverse direction of the driving direction by the biasing force of the weight spring 53.

A stopper plate 58 for restricting the end of the counterweight 51 that moves in the direction opposite to the driving direction is provided at the rear of the mechanism frame 46. An elastic member 54 having elasticity is disposed between the stopper plate 58 and the rear end portion of the guide case 52. The elastic member 54 has a tapered (conical) end portion 54a, a circular base portion 54b having a constant diameter, and a circular flange portion 54c extending laterally from the base portion 54b. As shown in fig. 6, substantially the entirety of the tip portion 54a enters from the rear opening of the guide housing 52 to the inside. The base 54b is set to an outer diameter that can enter the inside of the guide housing 52. The flange portion 54c is formed to have a diameter larger than that of the guide housing 52.

The flange 54c abuts the front surface of the stopper plate 58, and the elastic member 54 is sandwiched between the stopper plate 58 and the rear portion of the guide housing 52. Thereby, the left and right elastic members 54 are held so as not to fall off from the rear portion of the guide housing 52. The impact at the rear end position of the counterweight 51 is absorbed not by the counterweight 51 but by the elastic member 54 supported on the guide housing 52 side.

The stopper plate 58 for positioning the elastic member 54 is a common single member for the pair of left and right reaction absorbing mechanisms 50. Therefore, the stopper plate 58, which is a single member shown in fig. 7, extends from the rear of the guide housing 52 in the reaction absorbing mechanism 50 on the right side across to the rear of the second guide housing 52 in the reaction absorbing mechanism 50 on the left side. In the reaction absorbing mechanism 50 on the left side, the impact of the moving end of the second weight 51 in the opposite direction to the driving direction and the reaction of the driving operation in the impact mechanism 40 can be absorbed by the second weight 51 urged by the weight spring 53 contacting the second elastic member 54.

In the assembly process of the left and right reaction absorbing mechanisms 50, as shown in fig. 9, the distal end portion 54a of the elastic member 54 is inserted into the rear portion of the right-side guide housing 52 while the weight 51 is pushed forward, and the distal end portion 54a of the second elastic member 54 (not visible in the drawing) is inserted into the rear portion of the left-side second guide housing 52 while the second weight 51 is pushed forward. While holding the right-side elastic member 54 and the left-side second elastic member 54, one stopper plate 58 is inserted from below between the rear of the elastic members and the mechanism frame 46. The inserted stopper plate 58 is held at the insertion position by the left and right elastic members 54 being biased rearward by the weight springs 53. Thereafter, the main body case 11 is externally fitted to the mechanism frame 46, and thereby the stopper plates 58 are assembled so as not to be separated from the rear of the left and right elastic members 54. As described above, the left and right elastic members 54 are attached to the guide housing 52.

According to the driving tool 1 of the present embodiment configured as described above, the left and right weights 51 collide with the elastic members 54, respectively, and the reaction at the time of driving is absorbed or reduced. The elastic member 54 is supported on the side of the guide housing 52 which does not move, not on the side of the counterweight 51 which moves. Therefore, compared to the structure in which the elastic member 54 is attached to the counterweight 51 housed in the guide housing 52, it is easy to increase the diameter of the elastic member 54 as compared to the guide housing 52, for example, and to form the elastic member into a solid body. The elastic member 54 is made solid with a larger diameter, thereby improving its durability and impact absorption capability.

Further, since it is not necessary to attach the elastic member 54 in the guide housing 52, the degree of freedom of attachment of the elastic member 54 is improved. In the reaction absorbing mechanism 50 illustrated in the example, in a state where the elastic member 54 has the distal end portion 54a thereof positioned inside the guide housing 52, the elastic member 54 is supported by the guide housing 52 by being sandwiched between the stopper plate 58 and the rear end portion of the guide housing 52. This increases the size and makes the elastic member 54 solid, thereby improving the durability and shock absorbing ability thereof.

In the reaction absorbing mechanism 50 illustrated in the example, the counterweight spring 53 is housed in the guide case 52 to prevent the counterweight spring from buckling, and thus the biasing force to the counterweight 51 is reliably exerted. Further, since the end backup ring of the weight spring 53 is omitted, concentration of stress on the backup ring is avoided, durability is improved, and cost reduction is achieved.

In addition, the distal end portion 54a of the elastic member 54 has a tapered shape. This allows the elastic member 54 to be easily deformed. In addition, a tapered tip end portion 54a is located inside the guide housing 52. Therefore, the collision weight 51 deforms the tip end portion 54a largely on the small diameter side and deforms the tip end portion on the large diameter side. In this way, the tapered distal end portion 54a gradually increases in diameter in the guide shell 52, and the outward pressing force on the guide shell 52 decreases. This can reduce damage to the guide case 52.

The elastic member 54 has a flange portion 54c for positioning at an end surface opposite to the driving direction. Therefore, the state of being sandwiched by the stopper plate 58 is reliably performed, and the elastic member 54 is reliably positioned.

The reaction absorbing mechanism 50 is disposed in a pair on the left and right sides with respect to the impact mechanism 40. Thus, the movement of the two weights 51 for absorbing the reaction during the striking operation is performed with good left-right balance on the left and right sides of the impact actuator 3.

The stopper plate 58 for positioning the elastic member 54 is a common single member for the pair of left and right reaction absorbing mechanisms 50. Therefore, the operability of the stopper plate 58 and the assembly of the pair of left and right elastic members 54 can be improved.

In particular, in the reaction absorbing mechanism 50 illustrated, the distal end portion 54a of the elastic member 54 is supported in a state where the distal end portion 54a of the elastic member 54 is positioned inside the guide housing 52. Therefore, in the stage of assembling the reaction absorbing mechanism 50, in a state where the left and right elastic members 54 are held at the rear portions of the guide cases 52, respectively, when one stopper plate 58 is attached to the rear portion of the mechanism frame 46, the assembly of the left and right elastic members 54 is completed. In this regard, the assembling property of the reaction absorbing mechanism 50 is improved.

The elastic member 54 is provided with a circular base portion 54b and a flange portion 54c, which do not change in diameter. The base 54b is set to an outer diameter that can enter the inside of the guide housing 52. The flange portion 54c is formed to have a diameter larger than that of the guide housing 52. Therefore, when the guide housing 52 is displaced slightly rearward by, for example, a reaction during driving, it is elastically received by the flange portion 54c. This enables the flange portion 54c to function as a damper. This also improves the durability of the reaction absorbing mechanism 50.

Various modifications can be added to the above illustrated embodiments. For example, the elastic member 54 may be directly attached to the guide housing 52 by, for example, screwing, bonding, or the like.

Further, the configuration in which the distal end portion 54a of the elastic member 54 is positioned inside the guide case 52 is exemplified, but the elastic member 54 may be supported at a position retracted from the inside of the guide case 52.

Further, the structure in which the left and right elastic members 54 are sandwiched between the stopper plate 58 and the guide housing 52 by one stopper plate 58 is exemplified, but a structure in which the elastic members are sandwiched by two left and right stopper plates may be employed. The stopper plate may be provided integrally with the mechanism frame 46, or a part of the mechanism frame 46 may function as the stopper plate.

The elastic member may have a cylindrical shape other than a solid cylindrical shape, a prismatic shape, and a conical shape.

As the driving tool, a mechanical spring type driver using a rechargeable battery pack as a power source is exemplified, but the illustrated reaction absorbing mechanism 50, particularly, the elastic member supporting structure can be widely used for other types of driving tools such as a compressed air driven driver and a nailing machine.

Claims (9)

1. A driving tool, wherein,

the driving tool comprises:

an impact driver that impacts the drive member;

an impact spring for urging the impact driver in a driving direction;

a counterweight that moves in a direction opposite to the driving direction in synchronization with the movement of the impact driver in the driving direction to absorb a reaction of the impact driver during driving;

a guide case that accommodates the counterweight inside and guides movement of the counterweight; and

and an elastic member supported by the guide case so as to receive an impact from the weight at a moving end of the weight opposite to the driving direction.

2. The driving tool according to claim 1,

a limiting plate for limiting the movement of the counterweight in the opposite direction of the driving direction is arranged on the main body shell,

the elastic component is positioned by the limiting plate and the guide shell.

3. The driving tool according to claim 2,

the elastic member has a flange portion provided between the stopper plate and the end portion of the guide housing.

4. The driving tool according to any one of claims 1 to 3,

the driving tool has a counterweight spring for applying a force to the counterweight in a direction opposite to the driving direction, and the counterweight spring is housed in the guide case.

5. The driving tool according to claim 4,

the spring for the counterweight has no backup ring at both ends.

6. The driving tool according to any one of claims 1 to 3,

the elastic member has a tapered tip portion tapered toward the weight.

7. The driving tool according to any one of claims 1 to 3,

the elastic component is solid.

8. The driving tool according to any one of claims 1 to 3,

the driving tool has the guide shell on one side of the impact driver and a second guide shell on the other side,

the impact driver is provided with a second counterweight which is accommodated in the second guide shell and moves in the opposite direction of the driving direction synchronously with the movement of the impact driver in the driving direction.

9. The driving tool according to claim 8,

the driving tool has a stopper plate extending along an end of the guide shell and an end of the second guide shell,

the stopper plate restricts movement of the weight in the opposite direction to the driving direction via the elastic member, and restricts movement of the second weight in the opposite direction to the driving direction via a second elastic member.

Images