JP2008168360A - Power tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power tool which has a combination of a twisting force control device and an impact device, and where especially, the impact device can be manually switched to a starting state or a stopping state. <P>SOLUTION: The power tool is equipped with an electric motor 20 mounted in a housing 10, a transmission gear set 40, the twisting force control device 50, and the impact device 60. The twisting force control device 50 has an adjustment unit 53 for setting the maximum twisting force that the power tool 1 outputs by reciprocating between a first position and a second position in a housing 10 associated with the rotation. When the adjustment unit 53 is at the second position, the maximum twisting force outputted by the power tool 1 is the smallest, and the adjustment unit 53 prevents the impact device 60 from starting. The twisting force setting effect of the power tool 1 is not thereby interrupted by the impact device 60. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a handy power tool, in particular, a handy power tool having a function of adjusting a torsional force and a function of giving an impact to a workpiece during operation.

  The well-known electric impact wrench (Impact Wrench) includes an electric motor, a transmission gear set and an impact device. Among them, the speed change device decelerates the rotational motion by the transmission of the motor to a predetermined rotational speed and outputs it simultaneously. When the torsional force output by the power tool delivery shaft is lower than the required torsional force, the impact device applies a rapid intermittent impact force to the delivery shaft that is the same as the direction of rotation of the delivery shaft. Let it continue.

  Other known electric drivers include an electric motor, a transmission gear and a torsional force control device. Among them, the speed change device decelerates the rotational motion by the transmission of the motor to a predetermined rotational speed and outputs it simultaneously. The torsional force control device can prevent the workpiece from being damaged by setting the maximum torsional force output by the electric tool.

  The torsional force control device described above and the impact device described above are separately applied to completely opposite demands. Usually these two devices do not exist in the same power tool. This is because the two devices may be required at the same time. For example, when removing a tire with an electric wrench, an electric wrench having an impact function is necessary to loosen a rusty tire bolt or overcome another dismantling obstacle. In addition, when a tire is mounted, the power tool needs to have a twisting force setting function in order to prevent the twisting force output by the power tool from being too large and damaging the bolt that locks the tire. However, when these two types of devices are integrated into the same electric tool, the effect of electrically setting the torsion force is destroyed when the impact device is activated, and the impact device cannot be activated when the torsion force control device is activated.

  Therefore, how to dispose the above-described twisting force device and the impact device on the electric tool at the same time and avoid the above-mentioned situation is a problem to be solved in the industry.

  A main object of the present invention is to provide an electric tool having both a torsional force control device and an impact device, and in particular, to provide an electric tool in which the impact device can be manually switched between an activated state and a stopped state. is there.

  To achieve the above object, a power tool according to the present invention includes a housing, an electric motor mounted in the housing, a transmission gear set, a torsional force control device, and an impact device. The torsional force control device has an adjustment unit that sets the maximum torsional force output by the electric tool by reciprocating between a first position and a second position in the housing as the rotation occurs. When the adjustment unit is placed in the second position, the maximum twisting force output by the electric tool is the smallest, and the adjustment unit can prevent the impact device from being activated. Can be prevented from being destroyed.

Hereinafter, the present invention will be described based on examples and drawings. First, the description of the drawings is as follows.
FIG. 1 is a three-dimensional exploded view of the structure of an embodiment of the present invention.
FIG. 2 is a three-dimensional view of the structure of a part of the apparatus in the embodiment shown in FIG.
3 and 4 are schematic views showing the operating state of the embodiment shown in FIG.
As shown in FIGS. 1 to 3, the power tool 1 according to the embodiment of the present invention includes a housing 10, an electric motor 20, a battery set 30, a transmission gear set 40, a torsion force control device 50, and an impact device 60.

  The housing 10 includes a first half housing 11, a second half housing 12, a front housing 13 and a cap 14. The first and second half housings 11 and 12 are provided so as to be joined together, the front housing 13 is connected to the front ends of the first and second half housings 11 and 12, and the cap 14 has a protruding edge 141 at the base. And has a plurality of protruding blocks 142 arranged so as to place a certain distance on the inner wall surface. The base portion of the cap 14 is connected to the front housing 13, and the projecting edge portion 141 is positioned between the front housing 13 and the first and second half housings 11 and 12 to rotate the cap 14.

The electric motor 20 is fixed in the housing 10 and has a first delivery shaft 21.
The battery set 30 is connected to the housing 10 in a separable manner and can supply power to the electric motor 20.

  The transmission gear set 40 is mounted in the housing 10 and is connected to the first delivery shaft 21 of the electric motor 20, a first planetary gear stand 42 having a second sun gear 421, A first planetary gear 43 that is mounted on the planetary gear stand 42 and meshes with the first sun gear 41, a second planetary gear stand 44 having a third sun gear 441, and a second planetary gear stand 44 that is mounted on the second planetary gear stand 44. A first set planetary gear 45 meshed with the two sun gears 43, a third gear stand 46 having a second delivery shaft 461, and a third set fitted on the third planetary gear stand 46 and meshed with the third sun gear 44. A planetary gear 47, a first tooth ring 48 meshing with the first set planetary gear 43, a second tooth ring 49 meshing with the second set planetary gear 45 or the first planetary gear stand 42, and the front To accommodate the unit comprises a holding cylinder 491 that is fixed to the housing 10, a. As a result, the rotational movement by the transmission of the electric motor 20 can be reduced to a predetermined speed by the transmission gear set 40 and can be output via the second delivery shaft 461. In addition, the rotational speed of the second delivery shaft 461 can be changed by changing the position of the second tooth ring 49. Further, since the transmission gear set 40 is widely used for known electric tools, a detailed description thereof is omitted.

The torsional force control device 50 includes the following units.
The inner tooth ring 51 is mounted in the housing 10 so as to mesh with the third planetary gear 47, and has an operating end surface 511, and the operating end surface 511 is provided with a plurality of protrusions 512 provided at a certain distance. Have

  The housing seat 52 has a seat body 521 and a protruding column 524. The seat body 521 has a first end surface 522 and a second end surface 523, the protruding column 524 is formed by extending from the second end surface 523 of the seat body 521, and an outer thread 525 is formed on the outer column surface. It has an elongate groove 526 that is mounted in a relative position and formed along the axial direction of the protruding column 524. The seat body 521 has a plurality of elongated through holes 527 that penetrate the first and second end surfaces 522 and 523 of the seat body 521. The accommodating seat 52 has a shaft hole 528 that passes through the seat body 521 and the projecting column 524 along the axis of the seat body 521 and the projecting column 524. The housing seat 52 is fixed in the housing 10 so as to be positioned on one side of the inner tooth ring 51, and the first end surface 522 is provided so as to face the working end surface 511 of the inner tooth ring 51.

  The adjustment unit 53 includes an adjustment ring 531, a needle bearing 532, and a ring piece 533. The adjustment ring 531 has a first end surface 5311, a second end surface 5312 located on the opposite side, an inner ring surface 5313, and an outer ring surface 5314. The inner ring surface 5313 has an inner thread 5315 corresponding to the outer thread 525 of the projecting column 524, and the outer ring surface 5314 has a plurality of recessed grooves 5316 corresponding to the projecting blocks 142 located on the inner wall of the cap 14. Have The inner thread 5315 of the adjustment ring 531 meshes with the outer thread 525 of the projecting column 524 to connect the adjustment ring 531 and the projecting column 524 and at the same time, the recessed groove 5316 of the adjustment ring 531 and the projecting block of the cap 14. By coupling 142, the adjustment ring 531 is rotated with the rotation of the cap 14, and the adjustment ring 531 is reciprocated between the first position and the second position along the protruding column 524. The ring piece 533 has projecting fixing portions 5331 separately at two relative positions on the inner edge. The ring piece 533 is fitted on the protruding column 524 of the receiving seat 52, the protruding fixing portion 5331 is separately mounted in the elongated groove 526, and the second end surface 5312 of the receiving seat 52 and the first of the adjustment ring 531 are attached. It is positioned between the one end faces 5311. The needle bearing 532 is mounted on the second end surface 5312 of the adjustment ring 531.

The plurality of springs 54 are mounted in the elongated through holes 527.
The plurality of steel balls 55 are provided so as to abut against one end of the spring 54 and the working end surface 511 of the internal tooth ring.
The plurality of rods 56 penetrate the elongated through holes 527 separately, one end of which is stretched by the spring 54, and the other end abuts against the first end surface 5311 of the adjustment ring 531 via the ring piece 533.
Thereby, when the adjustment ring 531 is placed in the first position, the steel ball 55 can receive the first pressing force of the spring 54. When the adjustment ring 531 is placed in the second position, the steel ball 55 can receive the second pressing force of the spring 54. At this time, the second pressing force is larger than the first pressing force.

  When the internal gear ring 51 is maintained in a state where it does not move, the gear transmission system decelerates the power of the electric motor 20 and then outputs it via the second delivery shaft 461. Further, when the inner tooth ring 51 is maintained in a rotatable state, if the resisting force is applied to the rotation of the second delivery shaft 461, the inner tooth ring 51 is rotated and the power transmission of the entire transmission gear set 40 is released. Is possible. Further, when trying to rotate the inner tooth ring 51, it is necessary to overcome the force of the steel ball 55 that presses the operating end surface 511 against the protruding portion 512 on the operating end surface 511 of the inner tooth ring 51. Therefore, as the steel ball 55 increases the force on the operating end surface 511, it is necessary to increase the power transmitted to rotate the inner tooth ring 51. That is, the internal tooth ring 51 cannot be rotated unless a greater resistance force is applied to the second delivery shaft 461. At this time, the resistance force is the maximum twisting force output from the second delivery shaft 461. Therefore, when the adjustment ring 531 is placed at the second position, the force that the steel ball 55 applies to the operating end surface 511 of the inner tooth ring 51 is the largest. That is, the torsional force output from the second delivery shaft 461 is the largest. Further, when the adjustment ring 531 is placed at the first position, the force that the steel ball 55 applies to the operating end surface 511 of the inner tooth ring 51 is the smallest. That is, the twisting force output from the second delivery shaft 461 is the smallest.

  The impact device 60 includes a third delivery shaft 61, a transmission shaft 62, an impact unit 63, and an elastic unit 64. The third delivery shaft 61 is mounted in the cap 14, has a first coupling portion 611, and a part of the first delivery shaft 61 protrudes from the cap 14. Since the transmission shaft 62 is connected to the second delivery shaft 461, the transmission shaft 62 can rotate as the second delivery shaft 461 is driven. The impact unit 63 has a second coupling part 631. Further, since the impact unit 63 is fitted on the transmission shaft 62, the impact unit 63 can slide along the transmission shaft 62 so as to reciprocate between the third position and the fourth position. Further, when the impact unit 63 is placed at the third position, the second coupling portion 631 and the first coupling portion 611 of the third delivery shaft 61 are coupled, and the third delivery shaft 61 can be rotated. . When the transmission shaft 62 is placed at the fourth position, the second coupling portion 631 and the first coupling portion 611 of the third delivery shaft 61 are separated. The elastic unit 64 is mounted between the transmission shaft 62 and the impact unit 63, and can maintain the impact unit 63 in the third position.

When the adjustment ring 531 is placed at the first position, the second end face 5312 presses the impact unit 63 through the needle bearing 532 so as to maintain the third position, so that the impact unit 63 moves to the fourth position. Can not do.
As shown in FIGS. 3 and 4, when the adjustment ring 531 is moved to the second position by rotating the cap 14 (as shown in FIG. 3), the torsional force output from the second delivery shaft 461 is the largest. Further, when the third delivery shaft 61 receives a resistance force, the impact unit 63 moves from the third position to the fourth position due to the operation relationship between the second coupling portion 631 and the first coupling portion 611 of the third delivery shaft 61. When it moves and reaches the fourth position, it is separated from the third delivery shaft 61. Also, at the moment when the impact unit 63 is separated from the third delivery shaft 61, the elastic unit 64 pushes back so as to restore the impact unit 63 to the third position, and again the second coupling portion 631 of the impact unit 63 and the third delivery shaft 61 are restored. An impact effect is produced by coupling the first coupling portion 611. This impact effect lasts until the resistance force received by the third delivery shaft 61 is reduced.

  When the adjustment ring 531 is moved to the first position by rotating the cap 14, the twisting force output from the second delivery shaft 461 is the smallest. The adjusting ring 531 presses the impact unit 63 through the needle bearing 532 so as to maintain the third position. When the third delivery shaft 61 receives a resistance force, the impact unit 63 is pressed from the adjustment unit 53 and cannot move to the fourth position. Accordingly, the impact device 60 cannot produce an impact effect. If the torsional force received by the third delivery shaft 61 is greater than the torsional force output by the second delivery shaft 461, the internal tooth ring 51 is rotated and power transmission between the electric motor 20 and the second delivery shaft 461 is performed. To release. As a result, it is possible not only to ensure that the electric tool 1 outputs only a predetermined maximum torsional force, but even if a strong instantaneous torsional force is generated by the action of the impact device 60, It is possible to ensure that the object is not damaged.

The three-dimensional exploded view which shows the structure of the electric tool by one Example of this invention. The three-dimensional structure figure which shows the principal part of the electric tool shown in FIG. The schematic diagram which shows the operating state of the electric tool shown in FIG. The schematic diagram which shows the operating state of the electric tool shown in FIG.

Explanation of symbols

  1: electric tool, 10: housing, 11: first half housing, 12: second half housing, 13: front housing, 14: cap, 141: protruding edge, 142: protruding block, 20: electric motor , 21: first delivery shaft, 30: battery set, 40: transmission gear set, 41: first sun gear, 42: first planetary gear stand, 421: second sun gear, 43: first planetary gear, 44 : Second planetary gear stand, 441: third sun gear, 45: second planetary gear, 46: third planetary gear stand, 461: second delivery shaft, 47: third planetary gear, 48: first tooth Ring: 49: Second tooth ring, 491: Housing cylinder, 50: Torsional force control device, 51: Inner tooth ring, 511: Working end surface, 512: Projection, 52: Housing seat, 521: Seat body, 522: First end surface, 523: Second end surface, 524: Projection 525: Outer thread 526: Elongated groove 527: Elongated through hole 528: Shaft hole 53: Adjustment unit 531: Adjustment ring 5311: First end surface 5312: Second end surface 5313: Inner ring surface , 5314: outer ring surface, 5315: inner thread, 5316: recessed groove, 532: needle bearing, 533: ring piece, 5331: projecting fixing part, 54: spring, 55: steel ball, 56: rod, 60: impact device, 61: third delivery shaft, 611: first coupling portion, 62: transmission shaft, 63: impact unit, 631: second coupling portion, 64: elastic unit

Claims (4)

A housing, an electric motor, a transmission gear set, a torsional force control device, and an impact device;
The electric motor is fixed in the housing and has a first delivery shaft;
The transmission gear set is mounted in the housing and is mounted on the planetary gear stand directly or at least one sun gear connected to the first delivery shaft of the electric motor, one planetary gear stand, and A set of planetary gears to which driving force is indirectly transmitted from the sun gear set, and the planetary gear stand has a second delivery shaft,
The torsional force control device has an inner tooth ring, a receiving seat, an adjustment unit, a spring, a steel ball, and a rod body,
The inner tooth ring has an operating end surface, is mounted in the housing so as to mesh with the planetary gear, and the operating end surface has a plurality of protrusions arranged at predetermined intervals,
The receiving seat has a seat and a projecting column, the seat has a first end surface and a second end surface, and the projecting column has an outer thread on the outer column surface and the second end surface. The seat has a plurality of elongated through holes penetrating the first end surface and the second end surface, and the receiving seat is located along the axis of the seat body and the protruding column. A shaft hole penetrating the body and the protruding column, the receiving seat is fixed in the housing so as to be positioned on one side of the inner ring, and the first end surface is the operation of the inner ring Provided opposite the end face,
The adjustment unit includes an adjustment ring, and an inner ring surface of the adjustment ring includes an inner thread corresponding to an outer thread of the projecting column, and the inner thread and the outer thread of the projecting column. And the adjustment unit can be reciprocated between the first position and the second position along the projection column by rotating the adjustment ring. And
The plurality of springs are respectively mounted in the elongated through holes,
The plurality of steel balls are provided to abut against one end of the spring and the working end surface, respectively.
When the plurality of rods pass through the elongated through holes, one end is pressed by the spring, the other end is abutted against the adjustment unit, and the adjustment unit is in the first position, the steel ball Receives a first pressing force from the spring, and when the adjustment unit is in the second position, the steel ball receives a second pressing force from the spring, and the second pressing force is greater than the first pressing force. ,
The impact device includes a third delivery shaft, a transmission shaft, an impact unit, and an elastic unit, and the third delivery shaft is mounted in the housing and has a first coupling portion, and a part protrudes from the housing. The transmission shaft is connected to the second delivery shaft and can be rotated as the second delivery shaft is driven, the impact unit has a second coupling portion, and the impact unit is coupled to the transmission shaft. Reciprocating between a third position and a fourth position along the transmission shaft, and when the impact unit is in the third position, the second coupling portion and the first coupling portion of the third delivery shaft And the third delivery shaft can be rotationally driven, and when the transmission shaft is in the fourth position, the second coupling portion and the first coupling portion of the third delivery shaft are separated. The elastic unit is provided between the transmission shaft and the impact unit. Are power tools for maintaining the impact unit to the third position.   The housing has a rotatable cap, the cap has a plurality of projecting blocks arranged at predetermined intervals on an inner wall surface, and the adjustment ring has the projecting block on the inner wall of the cap on an outer ring surface. Corresponding to the projecting block, and the adjustment ring is rotated by rotating the cap, and the first position and the second position are moved along the projecting column. The power tool according to claim 1, which is capable of reciprocating between the two. The adjustment ring has a second end surface located on the opposite side to the first end surface;
The adjustment unit has a needle bearing mounted on the second end surface of the adjustment ring, and when the adjustment ring is in the first position, the second end surface of the adjustment ring is inserted through the needle bearing. The electric power tool according to claim 1, wherein the impact unit is pressed so as to be maintained at the third position, and the movement of the impact unit to the fourth position is restricted. The protruding column of the receiving seat has an elongated groove formed on the outer column surface at a relative position of two column surfaces and formed along the axial direction of the protruding column,
The adjustment unit has an annular piece provided with a projecting fixing portion at two relative positions on the inner edge, and the annular piece is fitted on the projecting column of the receiving seat, and the projecting fixing 4. The electric tool according to claim 3, wherein the portions are respectively mounted in the elongated grooves and are positioned between the second end surface of the receiving seat and the first end surface of the adjustment ring.

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