JP5662751B2 - Electric tool - Google Patents

Description

  The present invention relates to an electric tool having a shift lever capable of switching the rotation speed.

  Conventionally, in order to switch the rotation speed of the tip tool, a shift lever is provided in the electric tool (see, for example, Patent Document 1). Since the electric power tool described in Patent Document 1 is attached in a state where the shift lever is exposed to an easy-to-operate part, the operability is good and the user can easily switch the rotation speed at a desired timing. It is configured as follows.

JP 2010-046748 A

  By the way, since this electric power tool is attached in a state where the shift lever is exposed to an easy-to-operate part, the user may accidentally touch the shift lever during work. When the user unexpectedly touches the speed change lever, the rotational speed may be switched, and in some cases, the rotational speed may be switched without the user's knowledge.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an electric tool that can prevent a user from touching a transmission lever unexpectedly.

An electric power tool of the present invention includes a motor housed in a housing and serving as a driving source, and a transmission lever that transmits rotational power of the motor to a tip tool provided at a front end of the housing and can be operated from outside the housing. An electric power tool including a speed reduction mechanism unit capable of switching the number of rotations, wherein the power tool includes a cover that covers the shift lever and disables a switching operation.

  Further, in this electric tool, the speed reduction mechanism portion is configured to be able to switch the rotational torque by the tip tool by a torque setting handle operable from outside the housing, and the cover includes the shift lever and the torque setting handle. It is preferable that both are covered.

  The electric power tool further includes an illumination unit for irradiating a construction site of the tip tool, the torque setting handle is provided on the tip tool side with respect to the illumination unit, and the cover includes the illumination tool. It is preferable that all or part of the portion in the irradiation range from is cut out.

  In this electric power tool, it is preferable that the cover is fixed by a screw tool using a nut fixed to the housing.

  In the electric tool, the cover is preferably formed of a soft material.

  According to the electric tool of the present invention, it is possible to prevent the user from touching the speed change lever unexpectedly.

It is the side view which abbreviate | omitted the battery pack of one Embodiment of this invention. It is the front view seen from the front of embodiment same as the above. It is sectional drawing for demonstrating the fixing | fixed part of the cover of embodiment same as the above. It is the figure which abbreviate | omitted the cover of embodiment same as the above, (a) is a side view, (b) is a top view. (A) (b) is sectional drawing for demonstrating the internal mechanism of embodiment same as the above. It is a figure for demonstrating the clutch means of embodiment same as the above, (a) is a figure of the state in which motive power is transmitted, (b) is a figure of the state in which transmission of motive power was interrupted | blocked. It is a partially broken view which shows the side surface of other embodiment. It is the side view which abbreviate | omitted the cover and battery pack of embodiment same as the above. (A) is a side view of a state in which a part of the cover of the embodiment is mounted, and (b) is a sectional view of the cover. (A) is a side view in the state where a part of cover of the embodiment same as the above was mounted, and (b) is a sectional view.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. For convenience of explanation, the side on which the tip tool is attached in the electric power tool is defined as the front, and the motor side is defined as the rear.

  The electric power tool of this embodiment is a rechargeable electric screwdriver used when fastening or loosening a screw tool. The power tool of the present embodiment includes a power tool main body 1 and a battery pack (not shown) attached to the end of the grip portion 12 of the power tool main body 1. The electric tool main body 1 includes a main body portion 11 in which a motor 30, a speed reduction mechanism portion 4, and the like are incorporated, and a grip portion 12 that extends from the side of the main body portion 11. A tip tool such as a driver bit is detachably attached to the tip of the main body 11 of the electric tool (see, for example, FIG. 7).

  The outer periphery of the electric tool main body 1 is constituted by a housing 2. As shown in FIG. 5, the electric power tool main body 1 includes a motor 30 as a driving source, a speed reduction mechanism portion 4 for transmitting the rotational power of the motor 30 to the tip tool 7, and rotational power from the speed reduction mechanism portion 4. And a drive shaft portion 31 on which the tip tool 7 can be mounted. The motor 30 and the speed reduction mechanism 4 are accommodated in the housing 2. As shown in FIG. 1 and the like, the electric power tool has a switch part 14 for turning ON / OFF the rotation of the motor 30 in the main body part 11 of the electric tool main body 1, and the switch part 14 is a battery pack. And the motor 30 are electrically connected.

  The speed reduction mechanism unit 4 has a mechanism for reducing the rotational speed of the motor 30 and outputting a high torque rotation. As shown in FIG. 5, the speed reduction mechanism unit 4 includes a plurality of planetary gear trains (specifically, first, second, and third planetary gear trains 40, 45, and 50) housed in a gear box. It is comprised by. The speed reduction mechanism unit 4 of the present embodiment changes a gear ratio of the planetary gear trains 40, 45, and 50, thereby changing transmission means for switching between low speed rotation and high speed rotation, and a constant load on the rotary shaft part. And clutch means for cutting off the power from the motor 30 when applied.

  The first planetary gear train 40 includes a first sun gear 41 fixed to the output shaft of the motor 30, and a first ring gear 42 arranged and fixed in a state where the first sun gear 41 is positioned at the center. With. The first planetary gear train 40 includes a plurality of first planet gears 43 disposed between the first sun gear 41 and the first ring gear 42, and the first planet gears 43 as shafts. And a supported first carrier 44. The first planet gear 43 meshes with the first sun gear 41 and the first ring gear 42. The first carrier 44 has a second sun gear 46 protruding forward. Since the second sun gear 46 is integrated with the first carrier 44, it rotates together.

  The second planetary gear train 45 includes the above-described second sun gear 46 and a second ring gear 47 disposed with the second sun gear 46 positioned at the center. The second planetary gear train 45 also includes a plurality of second planet gears 48 disposed between the second sun gear 46 and the second ring gear 47, and the second planet gears 48. And a second carrier 49 having a gear formed radially outward. The second planet gear 48 meshes with the second sun gear 46 and the second ring gear 47. The second ring gear 47 is movable in the front-rear direction, and the second planet gear from the rear position (FIG. 5A) meshing with the first ring gear 42 and the second planet gear 48. It moves to a forward position (FIG. 5B) that meshes with 48 and the second carrier 49. Further, the second ring gear 47 has a slide groove 471 that is recessed on the outer peripheral surface over the entire length in the circumferential direction, and the transmission spring 24 connected to the transmission lever 23 is inserted into the slide groove 471. (See, for example, FIG. 7). As a result, the second ring gear 47 moves in the front-rear direction following the sliding movement of the speed change lever 23 and is further rotatable in the circumferential direction. The second carrier 49 has a third sun gear 51 protruding forward. Since the third sun gear 51 is integrated with the second carrier 49, it rotates together.

  The third planetary gear train 50 includes the above-described third sun gear 51 and a third ring gear 52 arranged with the third sun gear 51 positioned at the center. The third planetary gear train 50 includes a plurality of third planet gears 53 disposed between the third sun gear 51 and the third ring gear 52, and the third planet gear 53 as a shaft. And a third carrier 54 supported. The third planet gear 53 meshes with the third sun gear 51 and the third ring gear 52. The rotation of the third ring gear 52 is restricted by the clutch means, and normally does not rotate. The third carrier 54 is connected to the drive shaft portion 31 and outputs the rotation of the speed reduction mechanism portion 4 to the outside.

  When the output shaft of the motor 30 rotates in a state where the second ring gear 47 is positioned rearward (FIG. 5A), the first sun gear 41 and the first ring gear 42 fixed are first. Planet gear 43 revolves while rotating. Then, the first carrier 44 rotates and the second sun gear 46 rotates. When the second sun gear 46 is rotated, a second planet gear 48 is interposed between the second sun gear 46 and the second ring gear 47 that has become unrotatable by meshing with the first ring gear 42. Revolves while spinning. Then, following the revolution of the second planet gear 48, the second carrier 49 rotates, and the third sun gear 51 also rotates. When the third sun gear 51 rotates, the third planet gear 53 rotates and revolves between the third sun gear 51 and the third ring gear 52 whose rotation is restricted by the clutch means. The third carrier 54 rotates and the drive shaft 31 rotates.

  Thus, the electric power tool of this embodiment can decelerate via the three-stage planetary gear train, and in this case, high-torque rotation is executed at low-speed rotation.

  In the electric power tool of the present embodiment, the speed reduction mechanism unit 4 has a speed change unit. The speed change means of this embodiment follows the movement of the speed change lever 23 provided in the housing 2 and operable from the outside, the speed change spring 24 connecting the speed change lever 23 and the second ring gear 47, and the movement of the speed change lever 23. The second ring gear 47 is movable in the front-rear direction. Hereinafter, the operation will be described.

  When the user slides the shift lever 23 forward, the second ring gear 47 moves forward following the movement of the shift lever 23 (state shown in FIG. 5B). Then, the second ring gear 47 is disengaged from the first ring gear 42 and is engaged with the second planet gear 48 and the second carrier 49. At this time, since the second ring gear 47 is rotatable, it rotates together with the revolution of the second planet gear 48 and the rotation of the second carrier 49. That is, the rotation of the second sun gear 46 is transmitted as the rotation of the third sun gear 51 as it is.

  Thereby, the rotation of the output shaft of the motor 30 is decelerated through the first planetary gear train 40, but the rotation by the second sun gear 46 does not decelerate the second planetary gear train 45 without being decelerated as it is. Is transmitted to the third planetary gear train 50 through the first planetary gear train 50. Then, the rotation is decelerated by the third planetary gear train 50 and reaches the drive shaft portion 31. That is, in this case, the speed is reduced through the two-stage planetary gear train, and the rotation is performed at a higher speed and lower torque than the speed reduction mechanism via the three-stage planetary gear train.

  Next, the clutch means will be described. The rotation of the third ring gear 52 is restricted by the clutch means. As shown in FIG. 6, the third ring gear 52 has a plurality of convex portions 55 projecting forward in the axial direction in the circumferential direction. The convex portion 55 has inclined surfaces 56 on both side surfaces in the circumferential direction. The clutch means has a steel ball 57 and a steel ball urging means 58 that urges the steel ball 57 toward the third ring gear 52, and is urged toward the third ring gear 52. By engaging the steel ball 57 with the convex portion 55 of the third ring gear 52, the rotation of the third ring gear 52 is restricted.

  As shown in FIG. 5, the steel ball urging means 58 includes a plurality of pins 59 movable in the front-rear direction, a ring-shaped clutch plate 60 disposed on the front side of the pins 59, and a clutch plate 60. 3 and a clutch spring 61 that urges toward the ring gear 52 side. The steel ball urging means 58 further includes a cylindrical adjustment screw 62 having a flange portion 63 and a thread portion provided on the inner peripheral surface. The adjustment screw 62 includes a flange spring 63 and a clutch spring. 61 is disposed so as to contact the front end of 61. The adjustment screw 62 is screwed to a screw portion provided on the outer peripheral surface of the cylindrical portion 15 inside the main body portion 11. The adjusting screw 62 has a flange portion 63 fitted in the torque setting handle 64 and is configured to rotate following the rotation of the torque setting handle 64.

  When the user rotates the motor 30, the steel ball 57 is engaged with the convex portion 55 of the third ring gear 52 (the state shown in FIG. 6A), thereby restricting the rotation of the third ring gear 52. As a result, the third planet gear 53 revolves and the drive shaft 31 rotates. Here, when a certain load or more is generated in the rotation of the drive shaft portion 31, a load is generated in the revolution of the third planet gear 53 via the third carrier 54. On the other hand, since the third sun gear 51 continues to rotate, the rotation speed of the third planet gear 53 increases, whereby the third ring gear 52 receives a larger rotational force. As a result, as shown in FIG. 6B, the convex portion 55 of the third ring gear 52 pushes up the steel ball 57 against the urging force of the steel ball 57, and the convex portion 55 and the steel ball 57 are The engaged state is released. That is, in this state, the rotational force of the motor 30 is not transmitted to the drive shaft portion 31. Thereby, the electric tool of this embodiment prevents the rotational torque given to the construction object with the screw tool 91 and the like of the tip tool 7 from exceeding a predetermined torque.

  Furthermore, the electric power tool according to the present embodiment can set a value at which power is interrupted by the clutch means by the torque setting handle 64. When the user rotates the torque setting handle 64 and moves the adjustment screw 62 to the rear side, the clutch spring 61 is compressed, thereby increasing the biasing force to the steel ball 57. Then, the steel ball 57 is pressed against the third ring gear 52 with a force stronger than that before the adjustment screw 62 is moved. Thereby, the torque value at which the engagement state between the convex portion 55 of the third ring gear 52 and the steel ball 57 is released can be further increased. That is, the electric power tool according to the present embodiment can change the value at which power is interrupted by the clutch means depending on the rotational position of the torque setting handle 64, that is, the tightening torque to be applied to the construction object is set to a predetermined value. be able to.

  In the electric power tool of the present embodiment, the tightening torque can be switched by the torque setting handle 64 and the rotation speed can be switched by the speed change lever 23. In order to prevent unintended switching, A cover 8 is attached to these. As shown in FIGS. 1 and 2, the electric power tool of the present embodiment is configured to cover both the speed change lever 23 and the torque setting handle 64 with a cover 8 for disabling the switching operation.

  The cover 8 of the present embodiment includes a first cover portion 80 that covers the entire outer surface of the transmission lever 23, and a shaft portion insertion hole 87 that covers substantially the entire outer surface of the torque setting handle 64 and through which the drive shaft portion 31 is inserted. The 2nd cover part 81 which has is provided. The cover 8 has a configuration in which the first cover portion 80 and the second cover portion 81 are integrally molded. The cover 8 is formed of, for example, a soft material such as an elastomer or a synthetic resin. In particular, the cover 8 of the present embodiment is formed of a soft material. For example, even if the cover 8 collides with a surrounding object or a construction object during work, the device can prevent damage or damage to the collision object. Has been made.

  The cover 8 of the present embodiment has an insertion hole 82 through which the mounting screw 91 is inserted. On the other hand, the electric power tool main body 1 is provided with a mounting hole 25 as shown in FIGS. As shown in FIG. 3, a nut 22 fixed to the housing 2 is embedded in the mounting hole 25 at the back. The cover 8 has a screw tool 91 inserted through the insertion hole 82 of the cover 8 and the mounting hole 25 of the power tool main body 1, and the screw tool 91 is screwed into the fixed nut 22. Installed. As a result, it is possible to reliably prevent the clutch means and the number of revolutions from being switched unexpectedly. For example, when the same contents are repeatedly performed for a long time, the work efficiency can be improved.

  Moreover, the electric tool of this embodiment is provided with the illumination part 13 for irradiating a construction location. This illumination part 13 is comprised by the LED illumination which has the directivity provided in the front part of the electric tool. Here, since the torque setting handle 64 is provided on the tip tool 7 side of the illumination unit 13 in the electric tool, if the second cover unit 81 merely covers the torque setting handle 64, the illumination is performed. It interferes with the irradiation range 90 of the part 13. Therefore, the cover 8 of the present embodiment has a cutout portion 83 in which all or a part of the portion related to the irradiation range 90 from the illumination unit 13 is cut out. As shown in FIGS. 1 and 3, the notch 83 is provided in the second cover 81 and is configured not to affect the illumination effect of the illumination unit 13. Note that reference numeral 84 in FIG. 2 is an opening for allowing the illumination light of the illumination unit 13 to pass therethrough.

  Thus, since the electric tool of this embodiment is provided with the cover 8 that covers the speed change lever 23 and disables the switching operation, it is possible to prevent the user from accidentally operating the speed change lever 23 during work. . In addition, since the cover 8 is covered so that the shift lever 23 cannot be touched, erroneous operation can be reliably prevented with a simple configuration.

  In addition, since the power tool of this embodiment covers both the speed change lever 23 and the torque setting handle 64, the cover 8 can prevent not only an erroneous operation of the speed change lever 23 but also an erroneous operation of the torque setting handle 64. Unexpected behavior can be prevented. In addition, since the first cover 8 and the second cover 8 that cover the transmission lever 23 and the torque setting handle 64 are integrally formed, a clean and simple appearance can be exhibited.

  In the electric power tool of this embodiment, since the cover 8 is a part in which the part of the irradiation range 90 from the illumination unit 13 is partially or partially cut out, even if the torque setting handle 64 is covered, the illumination unit The lighting effect by 13 can be hardly affected.

  In the electric power tool of this embodiment, since the cover 8 is fixed by the screw tool 91 using the nut 22 fixed to the housing 2, it is possible to reliably prevent a change in torque and the number of rotations during the work. For example, when the same work is performed for a long time, work efficiency is increased. In addition, since the nut 22 is fixed to the housing 2, the cover 8 can be easily removed even when it is desired to change the torque or the rotational speed, and the workability is not significantly reduced.

  In the electric power tool of this embodiment, since the cover 8 is formed of a soft material, even if the electric tool collides with the product or the like while using the electric tool, the product or the like can be prevented from being damaged. it can.

  Next, another embodiment will be described with reference to FIGS. In addition, since this embodiment is the same as the embodiment shown in FIGS. 1 to 9 for the most part, the same portions are denoted by the same reference numerals, description thereof is omitted, and different portions are mainly described. In the electric power tool of this embodiment, the structure of the motor 30, the speed reduction mechanism 4 and the drive shaft 31 in the main body 11 is the same as that of the above embodiment.

  As shown in FIG. 7, the power tool of the present embodiment includes a power tool main body 1 and a battery pack 92 provided at one end of the power tool main body 1. The electric tool main body 1 includes a main body portion 11 in which a motor 30 and a speed reduction mechanism portion 4 are incorporated, and a grip portion 12 that is rotatably provided at one end of the main body portion 11. A tip tool 7 such as a driver bit is detachably attached to the tip of the main body 11 of the electric tool. In the electric power tool according to the present embodiment, since the grip portion 12 is rotatable, the user can freely change the shape to a shape suitable for the work content, and is easy to use.

  Unlike the cover 8 of the above-described embodiment, the cover 8 of the present embodiment has a first cover 88 (see FIG. 10) having a first cover portion 80 that covers the transmission lever 23 and a first cover 88 that covers the torque setting handle 64. A second cover 89 having two cover portions 81 (see FIG. 9). In the cover 8 of the present embodiment, the first cover 88 and the second cover 89 are separate independent covers 8. Note that the cover 8 of the present embodiment is formed of a synthetic resin.

  As shown in FIG. 10, the first cover 88 has a substantially C-shaped cross section, and an engaging convex portion 85 projects from the opposite side pieces toward the center. The first cover 88 covers the entire outer surface of the speed change lever 23 and prevents the speed change lever 23 from being operated from the outside.

  As shown in FIG. 9, the second cover 8 has a bottomed cylindrical shape, and a shaft portion insertion hole 87 through which the drive shaft portion 31 is inserted penetrates the bottom surface of the second cover 8. The second cover 8 is provided with an engaging protrusion 86 that protrudes toward the center side on the inner peripheral surface thereof. The second cover 89 covers the entire outer surface of the torque setting handle 64 so that the torque setting handle 64 cannot be operated from the outside.

  The main body 11 has a torque setting handle 64 at the front end, and a speed change lever 23 on the side surface. As shown in FIGS. 9A and 10B, the main body 11 has a first mounting recess 26 for detachably mounting a first cover 88 that covers the speed change lever 23. . Further, as shown in FIG. 9B, the main body 11 further has a second mounting recess 27 for detachably mounting the second cover 8.

  To attach the first cover 88 and the second cover 89 to the electric power tool main body 1, for example, the following is performed.

  The first cover 88 is pushed into the main body part 11 in a state where the opposing both side pieces are in contact with the main body part 11, and the engaging convex part 85 is inserted into the first mounting concave part 26. The cover 8 of the present embodiment is formed of a synthetic resin. However, since the main body 11 has a substantially cylindrical shape, it can be easily elastically deformed by being pushed in and can be easily mounted.

  Further, the second cover 89 is pushed from the front to the rear of the electric power tool main body 1 so that the engaging protrusion 86 is fitted into the second mounting recess 27. As shown in FIG. 9B and the like, the torque setting handle 64 has a slightly tapered shape toward the front, so that it can be easily elastically deformed by being pushed in when the second cover 89 is attached. And easy to install.

  As mentioned above, although the electric tool of this invention was demonstrated based on the electric screwdriver, this invention is applicable also to a drill etc., if it is a tool which has a transmission lever which changes rotation speed, and is limited to an electric screwdriver. It is not a thing.

DESCRIPTION OF SYMBOLS 1 Electric tool main body 11 Main body part 12 Grip part 13 Illumination part 14 Switch part 2 Housing 23 Shift lever 30 Motor 31 Drive shaft part 4 Deceleration mechanism part 64 Torque setting handle 7 Tip tool 8 Cover 80 First cover part 81 Second cover Cover part 83 Notch part 87 Shaft part insertion hole 90 Illumination range

Claims (5)

A motor housed in a housing and serving as a drive source;
An electric tool comprising a reduction mechanism that transmits rotational power of the motor to a tip tool provided at a front end of the housing and that can be switched in rotation speed by a shift lever that can be operated from outside the housing. ,
An electric tool comprising a cover that covers the speed change lever and disables a switching operation. The deceleration mechanism is configured to be able to switch the rotational torque by the tip tool by a torque setting handle that can be operated from outside the housing,
The power tool according to claim 1, wherein the cover covers both the shift lever and the torque setting handle. Further comprising an illumination part for irradiating the construction site of the tip tool,
The torque setting handle is provided closer to the tip tool than the illumination unit,
The electric tool according to claim 2, wherein the cover is formed by cutting out all or a part of a portion that covers an irradiation range from the illumination unit. The power tool according to any one of claims 1 to 3, wherein the cover is fixed by a screw tool using a nut fixed to the housing. The power tool according to any one of claims 1 to 4, wherein the cover is formed of a soft material.

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