JP6863813B2 - Attachments and tightening tools - Google Patents

Description

The present invention relates to an attachment that can be attached to and detached from the tightening tool, and a tightening tool having the attachment.

For tightening bolts and nuts with a large nominal diameter, a dedicated tightening tool that can output high torque and has a reaction force receiver is known. However, in general, since the dedicated tightening tool is heavy and expensive, an attachment with a booster that can be attached to and detached from the tightening tool whose output torque is not as high as that of the dedicated tightening tool has been proposed. .. For example, Patent Document 1 discloses a tightening auxiliary power unit that is detachably attached to an electric screwdriver and includes a planetary gear booster and a reaction force receiver.

Registered Utility Model No. 3129070

Since the tightening auxiliary power unit disclosed in Patent Document 1 is mounted coaxially with the output shaft of the electric screwdriver, the size of the electric screwdriver and the tightening auxiliary power unit as a whole increases in the extending direction of the output shaft. It ends up. Therefore, workability may be reduced depending on the environment in which the product is used, such as when working in a narrow space.

In view of such a situation, it is an object of the present invention to provide a technique for improving the workability of a tightening tool when the attachment is attached to the attachment that can be attached to and detached from the tightening tool.

According to one aspect of the present invention, there is provided a detachable attachment to a tightening tool having a final output shaft that is rotationally driven by the power of a motor. This attachment includes a planetary reducer, a reaction force receiving member, and a universal joint.

The planetary reducer has a first output shaft and a second output shaft that are coaxially arranged so as to be rotatable in opposite directions. The reaction force receiving member has an arm portion capable of contacting an external contact object. Further, the reaction force receiving member is connected to the first output shaft so as to rotate integrally with the first output shaft. The universal joint is configured to be able to transmit torque. In addition, the universal joint is configured so that the input side end where torque is input can be connected to the final output shaft of the tightening tool, and the output side end where torque is output is connected to the planetary reducer. .. The second output shaft is configured so that a socket that can be engaged with a bolt or nut can be connected so as to rotate integrally with the second output shaft. The reaction force receiving member is configured to rotate integrally with the first output shaft in the direction opposite to that of the second output shaft due to the reaction force during rotation of the socket. The universal joint is configured to transmit the torque of the final output shaft transmitted via the input side end to the planetary reducer via the output side end.

When the attachment of this embodiment is attached to the tightening tool, the torque of the final output shaft of the tightening tool is transmitted to the planetary reducer via the universal joint, and is further amplified by the planetary reducer. Therefore, it is possible to tighten bolts and nuts having a large nominal diameter by using a tightening tool that is lighter and cheaper than a dedicated tightening tool that receives a reaction force. Further, the tightening tool and the planetary reducer are connected via a universal joint. A universal joint is a shaft joint that can transmit torque between two rotating bodies and does not affect torque transmission even if the relative positions and angles of the rotating axes of the two rotating bodies change. .. Therefore, the user can freely change the relative position and angle between the rotation axis of the final output shaft of the tightening tool and the rotation axis of the planetary reducer according to the environment in which the bolts and nuts are tightened. be able to. As a result, the workability of the tightening tool when the attachment is attached can be improved.

A typical example of a tightening tool is an electric tool for tightening screws, bolts, nuts, etc. via a tip tool or a socket attached to a rotationally driven final output shaft. Typical examples of such a tightening tool include a screw driver and a driver drill. Further, the tightening tool is provided with a chuck that can mount the tip tool by tightening by rotating around a predetermined drive shaft, and the tip tool is rotationally driven by rotationally driving the final output shaft around the drive shaft. It may include a configured rotary tool (eg, an electric drill).

The planetary reducer is typically composed mainly of a planetary gear mechanism including a sun gear, a planetary gear, and an internal gear. The planetary reducer may be provided with only one planetary gear mechanism, or may be provided with two or more planetary gear mechanisms. The planetary reducer of this embodiment is configured to have two output shafts (a first output shaft and a second output shaft). Typically, the internal gears and carriers of the planetary gears can be the first output shaft and the second output shaft, respectively. The fact that the first output shaft and the second output shaft can rotate in opposite directions means that the reaction force (reaction) of the torque acting on one of the output shafts of the first output shaft and the second output shaft. ), It means that a torque (reaction torque) having a magnitude equal to this torque acts on the other output shaft in the opposite direction, and the other output shaft rotates in the opposite direction.

The reaction force receiving member may be directly connected to the first output shaft, or indirectly (in other words, via another intervening member that rotates integrally with the second output shaft). Good. Similarly, the socket may be directly connected to the second output shaft or indirectly (in other words, via another intervening member that rotates integrally with the second output shaft). There may be. Further, as an external contact object with which the arm portion of the reaction force receiving member comes into contact, a bolt or nut arranged in the vicinity or another member is generally used. Therefore, the reaction force receiving member is provided so that a plurality of types of reaction force receiving members having different shapes and sizes of the arm portions can be replaced according to the arrangement relationship between the bolt or nut to be tightened and the contacting object. It is preferable that the first output shaft is detachable from the first output shaft. The reaction force receiving member typically includes a base portion (typically a tubular portion) that is directly or indirectly connected to the first output shaft, and an arm portion. A portion extending in a direction (typically in the radial direction) intersecting the rotation axis of the first output shaft is included. As a whole, the arm portion may be formed in a straight line, or may be L-shaped or have a configuration including a bent portion.

The type of the universal joint is not particularly limited as long as torque can be transmitted between the two rotating bodies, and for example, a ball type or cross-axis type universal joint can be adopted. The input side end of the universal joint may be connected to the final output shaft of the tightening tool in a state where it can rotate integrally with the final output shaft of the tightening tool, and its shape and mounting mode are not particularly limited. Also, the input side end may be directly connected to the final output shaft of the tightening tool or indirectly (in other words, via another intervening member that rotates integrally with the final output shaft). It may be connectable.

According to one aspect of the invention, the planetary reducer may include at least one planetary gear mechanism including a sun gear, a planetary gear and an internal gear. The first output shaft may be the internal gear of the final stage planetary gear mechanism of at least one planetary gear mechanism, and the second output shaft may be the carrier of the final stage planetary gear mechanism. According to this aspect, a compact and rational attachment configuration can be realized. The "final stage planetary gear mechanism" here refers to the planetary gear mechanism when the planetary reducer has only one planetary gear mechanism, and when the planetary reducer has a plurality of planetary gear mechanisms. Refers to a planetary gear mechanism located on the most downstream side in the torque transmission direction.

According to one aspect of the present invention, the reduction ratio of the planetary reducer may be 10 or more. In other words, the planetary reducer may be configured to reduce the rotational speed to 1/10 or less to transmit power. According to this aspect, the torque transmitted from the final output shaft of the tightening tool via the universal joint can be increased by 10 times or more. This makes it possible to tighten bolts and nuts that require high torque by using a tightening tool with a relatively low output torque.

According to one aspect of the present invention, the reaction force receiving member has a plurality of convex portions formed in the circumferential direction around the rotation axis of the first output shaft, and the first output shaft is formed in the circumferential direction. It may have a plurality of recesses. The reaction force receiving member and the first output shaft may be connected to each other by engagement of a plurality of convex portions and a plurality of concave portions. Then, among the plurality of convex portions, the convex portion formed corresponding to the base end region of the arm portion and the corresponding concave portion are formed to be wider in the circumferential direction than the other convex portions and the other concave portions, respectively. It may have been done. According to this aspect, it is possible to secure the strength of the base end region of the arm portion to which a strong force is applied when the contact object receives a reaction force during rotation of the socket.

According to one aspect of the present invention, a motor, a final output shaft that is rotationally driven by the power of the motor, and an attachment that is detachably connected to the final output shaft so as to rotate integrally with the final output shaft. A provided tightening tool is provided. As the attachment, it can be adopted in the attachment according to any one of the above-described aspects. According to the tightening tool of this aspect, the same effect as each of the above-described aspects can be obtained by attaching the attachment.

It is a perspective view of the attachment attached to a driver drill. It is a side view of the attachment attached to a driver drill. It is a vertical sectional view of the attachment attached to a driver drill. It is sectional drawing of the attachment. It is sectional drawing in the VV line of FIG. It is sectional drawing of the universal joint corresponding to FIG. It is sectional drawing of the universal joint corresponding to FIG. It is a partially enlarged view of FIG. 4 which shows the main body unit. It is a partially enlarged view of FIG. 5 which shows the main body unit. It is sectional drawing in XX line of FIG. It is sectional drawing in the XI-XI line of FIG.

Hereinafter, embodiments will be described with reference to the drawings. In the following embodiment, an attachment 1 with a reaction force receiving member 4 attached to a tightening tool and configured to tighten a bolt or a nut will be illustrated. Further, as a tightening tool to which the attachment 1 can be attached and detached, an electric screwdriver drill 5 capable of screw tightening work and drilling work will be illustrated. Since the configuration of the driver drill 5 is well known, the driver drill 5 will be briefly described.

First, the appearance configuration of the driver drill 5 will be described. As shown in FIGS. 1 and 2, the outer shell of the driver drill 5 is mainly formed by the main body housing 51 and the handle 57. The main body housing 51 extends along a predetermined drive shaft A1. A chuck 58 configured so that a tip tool (typically a tip tool for screw tightening work or drilling work) can be attached to and detached from one end of the main body housing 51 in the extending direction of the drive shaft A1 is attached to the drive shaft A1. It protrudes along. The handle 57 is configured to be gripped by the user, and protrudes from the main body housing 51 in a direction intersecting the drive shaft A1 (a direction substantially orthogonal to the drive shaft A1). A trigger 571 that can be pressed by the user is provided at the base end of the handle 57. A rechargeable battery 9 is detachably mounted on the protruding end of the handle 57 via a battery mounting portion 575.

In the following, regarding the direction of the driver drill 5, for convenience of explanation, the extending direction of the drive shaft A1 is defined as the front-rear direction of the driver drill 5, the side on which the chuck 58 is arranged is the front side, and the opposite side is the rear side. Prescribe. Further, the direction orthogonal to the drive shaft A1 and corresponding to the extending direction of the handle 57 is defined as the vertical direction, the side on which the main body housing 51 is arranged is defined as the upper side, and the side on which the battery 9 is mounted is defined as the lower side. .. Further, the direction orthogonal to the front-rear direction and the left-right direction is defined as the left-right direction.

A speed change lever 511 is provided on the upper surface of the main body housing 51. The speed change lever 511 is arranged so as to be movable in the front-rear direction, and the user can switch the position of the speed change lever 511 to reduce the reduction ratio of the planetary speed reducer 53 (see FIG. 3) described later (that is, the spindle 55). The number of revolutions and output torque) can be switched. Further, a forward / reverse switching lever 513 is provided at the lower end of the main body housing 51. The forward / reverse switching lever 513 is arranged so as to be movable in the left-right direction, and the user can switch the position of the forward / reverse switching lever 513 to correct the rotation direction of the output shaft 521 (see FIG. 3) of the motor 52. It is possible to switch between the rolling direction (the direction in which the screw is tightened) and the reverse direction (the direction in which the screw is loosened).

Further, a torque adjusting ring 515 and a mode switching ring 517 are provided at the front end portion of the main body housing 51. The torque adjusting ring 515 is rotatably arranged around the drive shaft A1. By rotating the torque adjusting ring 515, the user can adjust the threshold value of the torque that interrupts the torque transmission by the clutch mechanism 54 described later. The mode switching ring 517 is rotatably arranged around the drive shaft A1. The user can switch the operation mode of the driver drill 5 by rotating the mode switching ring 517. There are two operation modes for the driver drill 5, a screw tightening mode in which the clutch mechanism 54 operates and a drill mode in which the clutch mechanism 54 does not operate.

Hereinafter, the internal structure of the driver drill 5 will be described.

As shown in FIG. 3, the main body housing 51 houses the motor 52, the planetary reducer 53, the clutch mechanism 54, and the spindle 55.

In the present embodiment, a small, high-output brushless DC motor is adopted as the motor 52. The motor 52 is arranged in the rear end portion of the main body housing 51 so that the rotating shaft of the output shaft 521 rotating together with the rotor (not shown) extends on the drive shaft A1. The planetary speed reducer 53 is configured as a speed reduction mechanism including a three-stage planetary gear mechanism, and is arranged on the front side of the motor 52. The planetary reducer 53 increases the torque input from the output shaft 521 of the motor 52 and outputs the torque to the spindle 55 as the final output shaft of the driver drill 5. As a result, the spindle 55 is rotationally driven around the drive shaft A1. The chuck 58 is coaxially connected to the spindle 55 by bolts 581 so as to rotate integrally with the spindle 55. The clutch mechanism 54 is arranged on the front side of the planetary reducer 53, and when the screw tightening mode is selected as the operation mode, when the torque output from the planetary reducer 53 reaches a set threshold value, the spindle 55 It is configured to block the torque transmission to.

Inside the handle 57, a switch 573 is housed behind the trigger 571. The switch 573 is turned on and outputs an on signal in response to the pressing operation of the trigger 571, and is turned off and outputs an off signal when the pressing of the trigger 571 is released. As described above, a battery mounting portion 575 is provided at the lower end of the handle 57. Further, in the lower end portion of the handle 57 (upper side of the battery mounting portion 575), a controller 577 that controls the driver drill 5 such as the drive control of the motor 52 is housed.

When performing screw tightening work or drilling work, the user attaches a tip tool corresponding to the desired work to the chuck 58. The chuck 58 is provided with a plurality of claws (not shown), and when the chuck 58 is rotated around the drive shaft A1 in a predetermined direction (when the chuck 58 is loosened), the claws open and when the chuck 58 is rotated in the opposite direction (chuck). It is configured to close the claws (when the 58 is tightened). The user can attach the tip tool by loosening the chuck 58, inserting the base end portion of the tip tool into the tool insertion hole 583 of the chuck 58, and tightening the chuck 58. When the trigger 571 is pressed by the user, the motor 52 is driven, and the tip tool mounted on the chuck 58 is rotationally driven around the drive shaft A1 integrally with the spindle 55 to carry out the work. ..

When the screw tightening mode is selected, when the torque output from the planetary reducer 53 reaches the threshold value, the clutch mechanism 54 operates to cut off the torque transmission to the spindle 55, and the screw tightening work is completed. To do. When the user releases the pressing operation of the trigger 571, the driving of the motor 52 is stopped. Further, when the drill mode is selected, the clutch mechanism 54 does not operate, and when the user releases the pressing operation of the trigger 571, the motor 52 stops and the rotation of the spindle 55 also stops. The drilling work is completed.

Hereinafter, an attachment 1 that is attached to the driver drill 5 and can tighten bolts or nuts will be described. As described above, the driver drill 5 is a tightening tool capable of performing screw tightening work and drilling work, and is a bolt or nut having a large nominal diameter (typically) that requires a high torque of approximately 100 Nm or more. Basically, it does not correspond to the tightening of bolts and nuts with a nominal diameter of 10 mm or more. The attachment 1 enables tightening of bolts and nuts having a large nominal diameter by using a driver drill 5.

As shown in FIGS. 1, 4, and 5, the attachment 1 includes a universal joint 2 and a main body unit 3. These detailed configurations will be described in order.

First, the universal joint 2 will be described. The universal joint 2 is a shaft joint that can transmit torque between two rotating bodies and does not affect torque transmission even if the relative position or angle between the rotating axes of the two rotating bodies changes. is there. As shown in FIGS. 6 and 7, the universal joint 2 of the present embodiment includes a first member 21, a second member 22, and a pin 25.

The first member 21 is configured as an input side member to which the torque of the spindle 55 of the driver drill 5 is transmitted (input). The first member 21 is formed in the shape of a long shaft as a whole, and has a shaft portion 211 extending linearly, a connecting portion 213 connected to one end of the shaft portion 211, and the other end of the shaft portion 211. Includes a spherical portion 215 connected to.

The connecting portion 213 is a portion that is detachably attached to the chuck 58 of the driver drill 5. In the present embodiment, the shaft portion 211 is formed in a round bar shape, whereas the connecting portion 213 is formed in a hexagonal columnar shape that can be inserted into the tool insertion hole 583 (see FIG. 1). The connecting portion 213 is an input side end portion in which the torque of the spindle 55 is input via the chuck 58 in the universal joint 2. It can also be said that the connecting portion 213 is an end portion located on the most upstream side in the torque transmission direction of the universal joint 2. The spherical portion 215 is formed in a spherical shape having a diameter larger than the diameter of the shaft portion 211. Further, the spherical portion 215 has a through hole 216 extending in a direction orthogonal to the axis A2 of the shaft portion 211. The through hole 216 is formed so that the diameter of the central portion is substantially equal to the diameter of the pin 25 and the diameter increases from the central portion toward the open ends on both sides. That is, the inner wall surface of the spherical portion 215 that defines the through hole 216 is formed as a substantially conical tapered surface from the central portion toward the open ends on both sides.

The second member 22 is configured as an output side member that outputs torque to the planetary reducer 30 described later. The second member 22 is formed as a columnar member having a diameter larger than that of the spherical portion 215 of the first member 21 as a whole. The second member 22 is formed with a recess 221 recessed from one end surface in the axis A3 direction toward the center. The spherical portion 215 is housed in the recess 221 and is supported by the second member 22 via a columnar pin 25 inserted through the through hole 216. As described above, the through hole 216 of the spherical portion 215 is formed so as to expand in diameter from the central portion toward the opening ends on both sides. Therefore, as shown by the dotted line in FIG. 4, the angle of the spherical portion 215 can be changed with respect to the axis A4 of the pin 25 until the tapered surface defining the through hole 216 abuts on the outer peripheral surface of the pin 25. Has been done. In this embodiment, the angle can be changed by about 20 degrees on one side (about 40 degrees on both sides) with respect to the axis A4. Further, as shown by the dotted line in FIG. 5, the spherical portion 215 is rotatable around the axis A4 of the pin 25 in the recess 221 within a predetermined angle range. In this embodiment, the angle can be changed by about 60 degrees around the axis A4.

With the above configuration, the user can set the relative position and angle of the axis A2 of the shaft portion 211 with respect to the axis A3 of the second member 22, that is, the relative position and angle of the first member 21 with respect to the second member 22. You can change it freely.

Further, as shown in FIGS. 6 and 7, the second member 22 is formed with a through hole 223 penetrating from the recess 221 to the other end along the axis A3. A shaft portion 225, which is an input shaft of the planetary reducer 30, which will be described later, is press-fitted into the through hole 223. That is, the shaft portion 225 is an output side end portion that outputs torque to the planetary reducer 30 in the universal joint 2. It can also be said that the shaft portion 225 is an end portion located on the most downstream side in the torque transmission direction of the universal joint 2.

Hereinafter, the main body unit 3 will be described. As shown in FIGS. 4 and 5, in the present embodiment, the main body unit 3 includes a planetary reducer 30, a spindle 37, a socket 40, and a reaction force receiving member 4. The planetary reducer 30, the spindle 37, the socket 40, and the reaction force receiving member 4 are arranged coaxially with respect to the axis A5 of the main body unit 3.

First, the planetary reducer 30 will be described. The planetary speed reducer 30 is a speed reduction mechanism (enhancement mechanism) that includes a plurality of planetary gear mechanisms and increases and outputs the torque transmitted via the universal joint 2. In the present embodiment, the reduction ratio of the planetary reducer 30 is set to 20. That is, the planetary reducer 30 can increase the input torque by 20 times. As shown in FIGS. 8 and 9, in this embodiment, the planetary reducer 30 includes two sets of planetary gear mechanisms. The two sets of planetary gear mechanisms include a first planetary gear mechanism 31 arranged on the upstream side in the torque transmission direction and a second planetary gear mechanism 32 arranged on the downstream side with respect to the first planetary gear mechanism 31. .. The first planetary gear mechanism 31 includes a sun gear 311 and a carrier 313, four planetary gears 317, and an internal gear 35. The second planetary gear mechanism 32 includes a sun gear 321 and a carrier 323, four planetary gears 327, and an internal gear 35.

In the present embodiment, the internal gear 35 is a member common to the first planetary gear mechanism 31 and the second planetary gear mechanism 32. Further, in the present embodiment, the internal gear 35 also serves as a housing forming the outer shell of the main body unit 3, and gear teeth are not formed on the inner peripheral portions of both end portions. The second member 22 of the universal joint 2 described above is arranged in one end of the internal gear 35 (a portion where gear teeth are not formed) so that the axis A3 thereof and the axis A5 of the main body unit 3 coincide with each other. There is. More specifically, the second member 22 has an end portion on the shaft portion 225 side arranged in one end portion of the internal gear 35, and is rotatably supported around the axis A5 by a ball bearing 27.

In the following, regarding the direction of the main body unit 3, for convenience, one end side of the internal gear 35 in which the second member 22 is arranged is referred to as an input side, and the other end side is referred to as an output side in the direction of the axis A5. To do.

The sun gear 311 of the first planetary gear mechanism 31 is fixed to the tip of the shaft portion 225 protruding from the second member 22 to the output side. The carrier 313 is rotatably arranged around the axis A5 and is rotated by four planetary gears 317 meshing with the sun gear 311 and the internal gear 35 revolving around the sun gear 311. The carrier 313 has a shaft portion 314 that projects toward the output side along the axis A5. The sun gear 321 of the second planetary gear mechanism 32 is fixed to the shaft portion 314 of the first planetary gear mechanism 31. The carrier 323 is rotatably arranged around the axis A5 and is rotated by four planetary gears 327 meshing with the sun gear 321 and the internal gear 35 revolving around the sun gear 321.

Further, as shown in FIGS. 8 and 10, the carrier 323 of the second planetary gear mechanism 32 has two engaging protrusions 324. The two engaging protrusions 324 are provided at positions corresponding to two of the four planetary gears 327 arranged so as to face each other. The two engaging projections 324 face each other with the axis A5 interposed therebetween, and project from the end surface of the carrier 323 on the output side toward the output side, respectively. The two engaging protrusions 324 are formed symmetrically with respect to the axis A5. Each engaging protrusion 324 is formed in a fan shape when viewed from the output side. That is, the two side surface 325s of the engaging projections 324 corresponding to the radius of the fan shape are formed as tapered surfaces that are inclined in the direction away from each other toward the radial outer side of the carrier 323. The angle formed by the side surface 325 (the central angle of the fan shape) is approximately 120 degrees. The side surface 325 is configured as a torque transmission surface that abuts on the side surface 375 of the engaging portion 374 of the spindle 37, which will be described later, to transmit torque.

As shown in FIGS. 8 and 9, the holding sleeve 38 is fixed in the output side end portion (the portion where the gear teeth are not formed) of the internal gear 35. The holding sleeve 38 is a stepped cylindrical member including a large diameter portion 381 and a small diameter portion 383. The outer diameter of the large diameter portion 381 is substantially equal to the inner diameter of the internal gear 35, and the outer diameter of the small diameter portion 383 is smaller than that of the large diameter portion 381. In the holding sleeve 38, the large diameter portion 381 is arranged on the input side and the small diameter portion 383 is arranged on the output side, and the large diameter portion 381 is fitted and fixed in the end portion of the internal gear 35 on the output side. Further, a metal bearing 39 is arranged in the end of the holding sleeve 38 on the large diameter portion 381 side (input side). Further, an annular groove 384 extending over the entire circumference is formed on the outer peripheral portion of the small diameter portion 383.

Further, as shown in FIGS. 1 and 11, a plurality of fitting recesses 351 are provided at the output-side end of the internal gear 35 in the circumferential direction around the axis A5. Each fitting recess 351 is a recess recessed in a rectangular shape from the output side end portion of the internal gear 35 toward the input side. In the present embodiment, three fitting recesses 351 are provided, one of which is formed to have a larger width in the circumferential direction than the other two. The fitting recess 351 is a portion to which the fitting convex portion 411 of the reaction force receiving member 4, which will be described later, is fitted.

The spindle 37 is configured so that a socket 40 described later can be attached and detached, and is held by an internal gear 35 as a housing so as to be rotatable integrally with the carrier 323 around the axis A5. As shown in FIGS. 8 and 9, in this embodiment, the spindle 37 includes a cylindrical portion 371, a flange portion 373, an engaging portion 374, and a socket mounting portion 377.

The cylindrical portion 371 is a portion that occupies approximately half of the input side of the spindle 37 in the axis A5 direction. The spindle 37 is made rotatable around the axis A5 by inserting the cylindrical portion 371 into the holding sleeve 38 and holding a part of the spindle 37 by the metal bearing 39. An annular groove extending over the entire circumference of the cylindrical portion 371 is formed in a portion of the cylindrical portion 371 on the output side of the portion held by the metal bearing 39, and an O-ring 372 is formed in this groove. It is installed. The O-ring 372 is provided as a sealing member for preventing grease from leaking from between the spindle 37 and the holding sleeve 38. The flange portion 373 is a portion that protrudes radially outward from the end portion of the cylindrical portion 371 on the input side, and is the end surface of the holding sleeve 38 (metal bearing 39) on the input side and the output side of the engagement projection 324 of the carrier 323. It is placed between the end face and the end face of.

The engaging portion 374 is a prismatic portion protruding from the flange portion 373 to the input side in the axis A5 direction. The engaging portion 374 is configured to engage with the engaging projection 324 of the carrier 323 described above so that torque can be transmitted to and from the engaging projection 324. Specifically, as shown in FIG. 10, the engaging portion 374 has a long side whose cross section orthogonal to the axis A5 is approximately equal to the diameter of the carrier 323, and the distance between the two engaging projections 324 of the carrier 323. It is configured in a rectangular shape with a short side shorter than the distance. The two side surfaces 375 corresponding to the long sides of the rectangular cross section of the engaging portion 374 are configured as torque transmission surfaces that abut on the side surface 325 of the engaging projection 324 and transmit torque.

The engaging portion 374 is arranged between the two engaging projections 324 of the carrier 323, and the protruding end face of the engaging portion 374 (the end face on the input side in the axis A5 direction) is in contact with the end face on the output side of the carrier 323. It is arranged between the holding sleeve 38 and the carrier 323. As shown by the dotted line in FIG. 10, the spindle 37 can rotate about the axis A5 with respect to the carrier 323 until the side surface 375 of the engaging portion 374 abuts on the side surface 325 of the engaging projection 324. In the present embodiment, as described above, since the angle formed by the two side surfaces 325 of the engaging projection 324 is approximately 120 degrees, the spindle 37 can rotate with respect to the carrier 323 within an angle range of approximately 60 degrees. is there.

The socket mounting portion 377 is a portion that protrudes from the cylindrical portion 371 to the output side in the axis A5 direction. As shown in FIGS. 8 and 9, the socket mounting portion 377 projects outward from the output side end of the internal gear 35 along the axis A5. The socket mounting portion 377 is configured so that the socket 40 can be attached and detached.

Since the configurations of the socket mounting portion 377 and the socket 40 themselves are well known, these will be briefly described. The socket mounting portion 377 formed in a prismatic shape is provided with a through hole 376 extending in a direction orthogonal to the axis A5 and through which a pin (not shown) for preventing disconnection is inserted. On the other hand, the socket 40 is formed in a tubular shape as a whole, and the inner peripheral portion of the base end portion thereof is configured to be fitted to the socket mounting portion 377. The base end portion of the socket 40 is fitted to the outside of the socket mounting portion 377, a pin (not shown) is inserted into a through hole (not shown) and a through hole 376 provided in the socket 40, and the pin is the outer circumference of the socket 40. The socket 40 is attached to the spindle 37 by being prevented from coming off from the side by an O-ring (not shown). Further, the inner peripheral portion of the tip portion of the socket 40 is configured to be engageable with a nut (not shown) (typically having a hexagonal cross section).

A plurality of types of sockets 40 that can be attached to and detached from the attachment 1 are prepared so as to be compatible with bolts and nuts having different sizes (diameters). The user can attach an appropriate socket 40 to the spindle 37 according to the size of the nut actually used.

In the planetary speed reducer 30 configured as described above, the torque transmitted via the universal joint 2 is transmitted in the order of the first planetary gear mechanism 31 and the second planetary gear mechanism 32. Specifically, the sun gear 311 of the first planetary gear mechanism 31 rotates integrally with the shaft portion 225 of the universal joint 2. The planetary gear 317 revolves around the sun gear 311 while rotating, thereby rotating the carrier 313 (shaft portion 314) around the axis A5 in the same direction as the shaft portion 225. Similar transmission is performed in the second planetary gear mechanism 32, and the carrier 323 rotates in the same direction as the shaft portion 225. Further, when the carrier 323 rotates, as shown by the dotted line in FIG. 10, the side surfaces 375 of the two engaging protrusions 324 provided at the output side end of the carrier 323 form both side surfaces of the engaging portion 374 of the spindle 37. It comes into contact with 375 and transmits the torque of the carrier 323 to the spindle 37. As a result, the spindle 37 and the socket 40 rotate integrally with the carrier 323.

On the other hand, in the first planetary gear mechanism 31 and the second planetary gear mechanism 32, the reaction force during rotation of the carriers 313 and 323 reverses the internal gear 35 to the carriers 313 and 323 via the planetary gears 317 and 327. It acts to rotate in the direction.

As described above, in the planetary reducer 30, the internal gear 35 and the carrier 323 are configured as two final output shafts that can rotate in opposite directions. For this reason, in the following, the internal gear 35 and the carrier 323 will also be referred to as the first output shaft 35 and the second output shaft 323, respectively.

Hereinafter, the reaction force receiving member 4 will be described. As shown in FIGS. 8 and 9, the reaction force receiving member 4 is connected to the first output shaft (internal gear) 30 and rotates integrally with the second output shaft (carrier) 323 via the spindle 37. It is configured to rotate in the direction opposite to that of the second output shaft 323 due to the reaction force during rotation of the sockets 40 that are possibly connected. The reaction force receiving member 4 abuts on an abutting object (for example, a bolt or nut arranged adjacent to each other) in the vicinity of the bolt or nut to be tightened, so that this reaction force is applied to the abutting object. It is a member that enables it to be received. In the present embodiment, the reaction force receiving member 4 includes a base portion 41 that is detachably configured at an end portion on the output side of the internal gear 35, and an arm portion 45 that protrudes from the base portion 41.

The base portion 41 is formed in a short cylindrical shape, and has an inner diameter substantially equal to the outer diameter of the small diameter portion 383 of the holding sleeve 38 described above. As shown in FIGS. 1 and 11, the base portion 41 includes a plurality of fitting convex portions 411 provided in the circumferential direction around the axis A5. Each fitting convex portion 411 is formed in a rectangular shape that can be fitted into the fitting concave portion 351 formed in the internal gear 35, and is provided so as to project outward in the radial direction. In the present embodiment, three fitting convex portions 411 are provided, and one of them is formed to have a larger width in the circumferential direction than the other two. The two narrow fitting protrusions 411 are formed with screw holes 412 extending in the radial direction.

The base portion 41 is inserted between the inner peripheral portion of the internal gear 35 and the outer peripheral portion of the small diameter portion 383 in a state where the fitting convex portion 411 is fitted into the fitting concave portion 351 of the internal gear 35, respectively. .. Further, the base portion 41 is fixed to the internal gear 35 and the holding sleeve 38 by screwing the screw 413 into the screw hole 412 and arranging the tip of the screw 413 in the groove 384 on the outer peripheral portion of the small diameter portion 383. Has been done. As a result, the reaction force receiving member 4 can rotate integrally with the internal gear 35.

As shown in FIGS. 1 and 8, in the present embodiment, the arm portion 45 is formed in a substantially L shape as a whole, and includes an extending portion 451 and a contact portion 452. The extending portion 451 is a portion connected to the base portion 41 and extending in the direction away from the internal gear 35 in the axis A5 direction. The root portion of the arm portion 45, that is, the base end region 450 of the extending portion 451 is the radial direction of one of the three fitting convex portions 411 of the base portion 41, which is wide. It is joined to the outside. The contact portion 452 is bent from the tip of the extending portion 451 and projects outward in the radial direction. The position of the contact portion 452 in the axis A5 direction is set to substantially the same position as the tip of the socket 40 when the socket 40 is mounted on the spindle 37.

A plurality of types of reaction force receiving members 4 having different lengths and shapes of the arm portions 45 are prepared so as to correspond to various arrangement relationships between the bolts or nuts to be fastened and the objects to be contacted. The user can connect an appropriate reaction force receiving member 4 to the internal gear 35 according to the arrangement relationship between the bolt or nut to be fastened and the object to be contacted.

Hereinafter, the nut tightening work and the nut loosening work will be briefly described as a work example using the driver drill 5 to which the attachment 1 is attached.

When tightening the nut, the user switches the forward / reverse switching lever 513 to a position corresponding to the forward rotation direction. The operation mode of the driver drill 5 may be either a screw tightening mode or a drill mode, but in the screw tightening mode, the user rotates the torque adjusting ring 515 to appropriately set a threshold value. .. The threshold value may be set in consideration of the reduction ratio of the planetary speed reducer 30 being 20. Similarly, the user may switch the shift lever 511 in consideration of the fact that the output torque of the spindle 55 changes according to the switching position of the shift lever 511. The user loosens the chuck 58, inserts the connecting portion 213 of the attachment 1 into the tool insertion hole 583, and tightens the chuck 58 to attach the attachment 1 to the driver drill 5 via the connecting portion 213.

Subsequently, the user engages the socket 40 connected to the attachment 1 with the nut. At this time, depending on the working environment, as shown in FIG. 3, a space is secured so that the drive shaft A1 of the driver drill 5, the axis A2 of the shaft portion 211 of the attachment 1 and the axis A5 of the main body unit 3 can be arranged in a straight line. It may not be possible. As described above, the shaft portion 211 of the universal joint 2 is configured so that the position and angle relative to the second member 22 (that is, the position and angle relative to the main body unit 3) can be freely changed (that is, the position and angle relative to the main body unit 3). See FIGS. 4 and 5). That is, the user can freely change the relative arrangement relationship between the driver drill 5 to which the shaft portion 211 is connected and the main body unit 3. Therefore, the user can appropriately adjust the arrangement relationship between the two according to the work environment.

Further, in order to engage the socket 40 having a polygonal cross section (typically a hexagonal shape) with the nut, it is necessary to adjust the position of the socket 40 with respect to the nut in the circumferential direction around the axis A5. As described above, in the present embodiment, the spindle 37 to which the socket 40 is connected is rotatably arranged with respect to the carrier 323 of the planetary reducer 30 within an angle range of approximately 60 degrees around the axis A5. (See FIG. 10). Therefore, the user can rotate the socket 40 within this angle range and easily engage it with the nut.

When the user presses the trigger 571, the controller 577 drives the motor 52 so that the output shaft 521 rotates in the forward rotation direction. As a result, the spindle 55 is rotationally driven around the drive shaft A1 via the planetary reducer 53. The torque of the spindle 55 (chuck 58) is transmitted to the universal joint 2 via the connecting portion 213, and further transmitted to the planetary reducer 30 via the shaft portion 225. The socket 40, which is integrally and rotatably connected to the second output shaft 323 of the planetary reducer 30 via the spindle 37, is rotated in the direction of tightening the nut. As described above, the reduction ratio of the planetary reducer 30 is 20. Therefore, when the torque of the spindle 55 of the driver drill 5 is 5 N ・ m, the torque of the second output shaft 323 is amplified to 100 N ・ m, which is sufficient for tightening the nut having a nominal diameter of M12.

When the socket 40 rotates integrally with the second output shaft 323, a torque in the opposite direction acts on the first output shaft 35 as a reaction force. Therefore, the reaction force receiving member 4 connected to the first output shaft 35 starts rotating around the axis A5 in the direction opposite to the socket 40 at a certain point. The reaction force receiving member 4 rotates, and the arm portion 45 (specifically, the abutting portion 452) abuts on an abutting object (for example, another nut or bolt) arranged adjacent to the nut to be fastened. Then, the reaction force due to the rotation of the socket 40 is received by the contact object via the reaction force receiving member 4. When a reaction force is received by the contact object via the arm portion 45, a strong force is applied to the base end region 450 of the arm portion 45 in the circumferential direction around the axis A5. On the other hand, as described above, the fitting convex portion 411 formed corresponding to the proximal end region 450 and the fitting concave portion 351 corresponding thereto have different widths in the circumferential direction, respectively. Its strength is ensured by being formed wider than the joint convex portion 411 and the other fitting recesses 351. This makes it possible to reduce the possibility that the arm portion 45 will be damaged.

When the user confirms that the nut is seated and releases the pressing operation of the trigger 571, or when the clutch mechanism 54 operates in the screw tightening mode, the tightening operation is completed.

When loosening the nut, the user switches the forward / reverse switching lever 513 to a position corresponding to the reverse direction, and engages the socket 40 connected to the attachment 1 with the nut in the same manner as in the tightening work. Then, by pressing the trigger 571, the motor 52 is driven so that the output shaft 521 rotates in the reverse direction, and the pressing operation of the trigger 571 is released as appropriate to complete the loosening operation.

As described above, when the attachment 1 of the present embodiment is attached to the driver drill 5, the torque of the spindle 55, which is the final output shaft of the driver drill 5, is transmitted to the planetary reducer 30 via the universal joint 2. Further, it is amplified by the planetary reducer 30. In particular, in the present embodiment, since the reduction ratio of the planetary reducer 30 is 20, the planetary reducer 30 can increase the torque transmitted via the universal joint 2 by 20 times. Therefore, it is possible to tighten bolts and nuts having a large nominal diameter by using a driver drill 5 which is lighter and cheaper than a dedicated tightening tool for receiving a reaction force.

Further, the universal joint 2 that connects the driver drill 5 and the planetary reducer 30 affects torque transmission even if the relative positions and angles of the axis A2 of the shaft portion 211 and the axis A5 of the planetary reducer 30 change. It is a shaft joint that does not occur. Therefore, the user can freely change the relative position and angle of the driver drill 5 with respect to the main body unit 3 according to the environment in which the bolts and nuts are tightened. As a result, the workability of the driver drill 5 when the attachment 1 is attached can be improved.

Further, in the present embodiment, the reaction force receiving member 4 is connected to the internal gear 35 of the second planetary gear mechanism 32. Then, the socket 40 is rotatably attached to and detached from the carrier 323 of the second planetary gear mechanism 32 via the spindle 37, integrally with the carrier 323. As a result, a compact and rational attachment 1 configuration is realized.

The correspondence between each component of the present embodiment and each component of the present invention is shown below. The driver drill 5, the motor 52, and the spindle 55 are configuration examples corresponding to the "fastening tool", the "motor", and the "final output shaft" of the present invention, respectively. Attachment 1 is a configuration example corresponding to the "attachment" of the present invention. The planetary reducer 30, the internal gear 35, and the carrier 323 are configuration examples corresponding to the "planetary reducer", the "first output shaft", and the "second output shaft" of the present invention, respectively. The reaction force receiving member 4 and the arm portion 45 are configuration examples corresponding to the "reaction force receiving member" and the "arm portion" of the present invention, respectively. The universal joint 2, the connecting portion 213, and the shaft portion 225 are configuration examples corresponding to the "universal joint", the "input side end portion", and the "output side end portion" of the present invention, respectively. The socket 40 is a configuration example corresponding to the "socket" of the present invention.

The first planetary gear mechanism 31 and the second planetary gear mechanism 32 are configuration examples corresponding to the "planetary gear mechanism" of the present invention, respectively. The solar gears 311 and 321 are configuration examples corresponding to the "solar gear" of the present invention, respectively. The planetary gears 317 and 327 are configuration examples corresponding to the "planetary gears" of the present invention, respectively. The internal gear 35 is a configuration example corresponding to the “internal gear” of the present invention. The three fitting convex portions 411 are configuration examples corresponding to the "plurality of convex portions" of the present invention. The three fitting recesses 351 are configuration examples corresponding to the "plurality of recesses" of the present invention.

The above embodiment is merely an example, and the attachment and the tightening tool according to the present invention are not limited to the configurations of the illustrated attachment 1 and the driver drill 5. For example, the changes illustrated below can be made. It should be noted that only one or a plurality of these modifications can be adopted in combination with the attachment 1 or the driver drill 5 shown in the embodiment, or the invention described in each claim.

In the above embodiment, the driver drill 5 is mentioned as an example of the tightening tool, but the tightening tool to which the attachment 1 can be attached and detached is not limited to the driver drill 5. For example, it may be a screwdriver. Further, the tightening tool is not limited to the tightening tool for tightening screws, and is provided with a chuck that can mount the tip tool by tightening by rotating around the drive shaft A1 and rotates the final output shaft around the drive shaft A1. It may be a rotary tool (for example, an electric drill) configured to rotationally drive the tip tool by driving it.

The universal joint 2 may be capable of transmitting the torque transmitted via the input side end portion to the planetary reducer 30 via the output side end portion, and its configuration is not limited to the example of the above embodiment. For example, a cross shaft type universal joint may be adopted instead of the ball type universal joint. Further, the number of planetary gear mechanisms included in the planetary speed reducer 30 is not limited to two, and may be one or three or more. Further, the configuration of each planetary gear mechanism can be changed as appropriate. The reduction ratio of the planetary reducer 30 is not limited to 20, but in order to make it possible to tighten bolts and nuts that require high torque by using a tightening tool with a relatively low output torque, The reduction ratio is preferably 10 or more.

The reaction force receiving member 4 may not be directly connected to the internal gear 35, but may be connected to another member that can rotate integrally with the internal gear 35. Further, the internal gear 35 and the reaction force receiving member 4 do not necessarily have to be connected by the engagement of the fitting concave portion 351 and the fitting convex portion 411, and other connecting structures may be adopted. On the other hand, the socket 40 may be connected to a shaft portion provided as a part of the carrier 323, such as the shaft portion 314 of the carrier 313, instead of the spindle 37 which is a member separate from the carrier 323.

1: Attachment 2: Universal joint 21: First member 211: Shaft part 213: Connecting part 215: Spherical part 216: Through hole 22: Second member 221: Recessed part 223: Through hole 225: Shaft part 25: Pin 27: Ball Bearing 3: Main unit 30: Planetary gear reducer 31: First planetary gear mechanism 311: Sun gear 313: Carrier 314: Shaft part 317: Planetary gear 32: Second planetary gear mechanism 321: Sun gear 323: Carrier 324: Engagement Protrusion 325: Side 327: Planetary gear 35: Internal gear (first output shaft)
351: Fitting recess 37: Spindle (second output shaft)
371: Column part 372: O ring 374: Engagement part 375: Side surface 376: Through hole 377: Socket mounting part 38: Holding sleeve 381: Large diameter part 383: Small diameter part 384: Groove 39: Metal bearing 4: Reaction force receiver Member 41: Base portion 411: Fitting convex portion 412: Screw hole 413: Screw 45: Arm portion 450: Base end region 451: Extension portion 452: Contact portion 40: Socket 5: Driver drill 51: Main body housing 511 : Shift lever 513: Forward / reverse switching lever 515: Torque adjustment ring 517: Mode switching ring 52: Motor 521: Output shaft 53: Planetary reducer 54: Clutch mechanism 55: Spindle 57: Handle 571: Trigger 573: Switch 575: Battery Mounting part 577: Controller 58: Chuck 581: Bolt 583: Tool insertion hole 9: Battery A1: Drive shaft A2: Axis line A3: Axis line A4: Axis line A5: Axis line

Claims (5)

An attachment that can be attached to and detached from a tightening tool equipped with a final output shaft that is rotationally driven by the power of a motor.
A planetary reducer having a first output shaft and a second output shaft arranged coaxially so as to be rotatable in opposite directions.
A reaction force receiving member having an arm portion capable of contacting an external contact object and connected to the first output shaft so as to rotate integrally with the first output shaft.
A universal joint capable of torque transmission, the input side end to which the torque is input is configured to be connectable to the final output shaft of the tightening tool, and the output side end to which the torque is output. Is a universal joint connected to the planetary reducer ,
It is configured so that a socket that can be engaged with a bolt or nut can be connected, and includes a spindle arranged coaxially with the second output shaft.
The reaction force receiving member is configured to rotate integrally with the first output shaft in a direction opposite to that of the second output shaft due to the reaction force during rotation of the socket.
The universal joint is configured to transmit the torque of the final output shaft transmitted via the input side end portion to the planetary reducer via the output side end portion .
The second output shaft includes an engaging protrusion and has an engaging projection.
The spindle includes an engaging portion that can be engaged with the engaging projection of the second output shaft, and the torque transmitted by the engagement between the engaging portion and the engaging projection causes the second output shaft. It is configured to rotate integrally with
The second output shaft and the spindle are located between a position where the engaging projection and the engaging portion engage with each other and a position where the engaging projection and the engaging portion are separated from each other. An attachment characterized by being able to rotate relative to the axis of the output shaft. The attachment according to claim 1.
The planetary reducer comprises at least one planetary gear mechanism including a sun gear, a planetary gear and an internal gear.
The first output shaft is the internal gear of the planetary gear mechanism in the final stage of the at least one planetary gear mechanism.
The second output shaft is an attachment characterized by being a carrier of the planetary gear mechanism in the final stage. The attachment according to claim 1 or 2.
An attachment characterized in that the reduction ratio of the planetary reducer is 10 or more. The attachment according to any one of claims 1 to 3.
The reaction force receiving member has a plurality of convex portions formed in the circumferential direction around the rotation axis of the first output shaft.
The first output shaft has a plurality of recesses formed in the circumferential direction.
The reaction force receiving member and the first output shaft are connected to each other by engagement of the plurality of convex portions and the plurality of concave portions.
Of the plurality of convex portions, the convex portion formed corresponding to the base end region of the arm portion and the corresponding concave portion are each wider in the circumferential direction than the other convex portion and the other concave portion. An attachment characterized by being formed. With the motor
The final output shaft, which is rotationally driven by the power of the motor,
A tightening tool comprising the attachment according to any one of claims 1 to 4 , which is detachably connected to the final output shaft so as to rotate integrally with the final output shaft.

Images