JP3098845B2 - Rotary tool - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary tool such as an electric screwdriver or an electric wrench, and more particularly to a rotary tool capable of automatically locking and automatically releasing an output shaft.

[0002]

2. Description of the Related Art In a rotary tool such as an electric screwdriver or an electric wrench, it is possible to lock the rotation of an output shaft so that it can be used as a hand-rotated type. In order to be able to perform auxiliary tightening by hand when not tight enough,
It is very useful, and in providing this lock function, an auto release that automatically releases the lock when the motor is rotated while in the locked state, and an auto release that automatically locks when the motor is stopped It is preferable from the viewpoint of convenience that the lock is performed.

[0003] Japanese Patent Laid-Open No. Hei 3-251 discloses an apparatus having such an automatic lock and automatic release function.
No. 374 is disclosed. As shown in FIG. 8, the ring body 51 is non-rotatably disposed on the inner peripheral surface of the gear case 6 provided in the main body 1, and the ring body 51 of the output shaft 7, which is the output shaft side member. A plurality of projections 70 are protruded radially and equidistantly from the outer peripheral surface of the enclosed portion, and the input shaft side member connected to the driving source includes the output shaft 7 outer peripheral surface and the ring body 51 inner peripheral surface. Between and the output shaft 7
Are provided between the plurality of protrusions 70 in the above, so that the protrusions 36 and the protrusions 70 are arranged at intervals in the circumferential direction.

In this case, since the outer peripheral surfaces on both sides of the projection 70 on the output shaft 7 are inclined surfaces 71 on which the projection 70 side is lowered, the outer peripheral surface and the ring body 51 are provided on both sides of the projection 70. A wedge-shaped space having a different inclination direction is formed between the projection 70 and the peripheral surface.
Roller-shaped lock members 50a and 50b are respectively provided in these wedge-shaped spaces provided on both sides of the input shaft side member and between the protrusion 36 and the protrusion 70 of the input shaft side to form lock means. I have. The lock member 50a is for locking in one direction rotation, and the lock member 50b is for locking in another direction rotation. The diameter of the lock members 50a and 50b is smaller than the height of the wedge-shaped space on the side of the projection 70, and
The lock members 50a and 50b are in a floating state when located on the protrusion 70 side because they are larger than the height of the portion on the 6 side. The output shaft 7 is locked by being engaged with the peripheral surface.

In this device, when the input shaft side member is driven to rotate, the projection 36 is locked by the lock member 50 in accordance with the direction of rotation.
The output shaft 7 is rotated by pressing the projection 70 of the output shaft 7 through one of the a and 50b. At this time, one of the lock members 50a, 5 sandwiched between the protrusion 36 and the protrusion 70
0b is located in a floating region in the wedge-shaped space portion by being pushed by the projection 36, that is, a portion near the projection 70,
Since the other lock members 50b, 50a are located in the floating region in the wedge-shaped space due to their inertia, the lock members 50a, 50b do not hinder the rotation of the output shaft 7.

[0006] Then, with the rotary drive source stopped,
If the main body 1 is rotated in the tightening direction around the axis of the output shaft 7 in order to perform manual tightening, the lock member 50b is rotated by the relative rotation generated between the main body 1, that is, the ring body 51 and the output shaft 7. Although the lock member 50a keeps its position in the floating region near the projection 70, the locking member 50a separates from the projection 70 and moves to the biting portion side in the wedge-shaped space by the rolling caused by the relative rotation. And the output shaft 7 are integrated. That is, the free rotation of the output shaft 7 is locked by the lock member 50a, and
And the screw and nut can be manually tightened. The transition to the locked state is automatically performed as described above. When the main body 1 is turned in the opposite direction to loosen the screws and nuts, the lock member 50b locks the output shaft 7 on the contrary, and enables manual return. Auto-lock and auto-release in both forward and reverse rotation directions are possible.

[0007]

However, in the above, the automatic release is surely performed by pressing the lock member 50a or the lock member 50b by the projection 36 of the input shaft side member. Had. That is, the lock members 50a, 50
The movement of b to the biting region in the wedge-shaped space portion depends on the rolling caused by the relative rotation between the ring body 51 and the output shaft 7 as described above, and therefore, the direction of the tool (gravity) Depending on the direction), during auto-locking, a state may occur in which all of the plurality of lock members 50a or lock members 50b do not move to the biting regions in the respective wedge-shaped spaces. FIG.
Of the three lock members 50a, only one located on the right side in the figure is located in the biting region and locks, but the other two lock members 50a are in the floating region in the wedge-shaped space. It shows a state in which it stays.

In such a state, not only the lock becomes unstable, but also the load which should be shared by a plurality of lock members is concentrated on one lock member.
When the load is large (when the tightening torque is large)
In some cases, the output shaft or the ring body may be damaged by deformation of a portion of the ring member in contact with the lock member. SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to enable auto-locking and auto-releasing to increase the reliability of auto-locking and prevent damage due to insufficient locking. It is to provide a rotating tool that can.

[0009]

According to the present invention, there is provided a power transmission connecting portion which is connected to an input shaft side member and an output shaft side member located coaxially with a play within a predetermined angle. A wedge-shaped space is formed between the inner peripheral surface of the non-rotatable ring body surrounding the output shaft side member and the outer peripheral surface of the output shaft side member to allow the lock member to bite and play freely, and the input shaft side member has In the rotary tool forming a release member that pushes the lock member toward the floating region side in the wedge-shaped space portion, the plurality of lock members respectively arranged in the plurality of wedge-shaped space portions are connected by a connecting body. Has features.

[0010]

According to the present invention, when a plurality of locking members move toward the biting region side of the wedge-shaped space to perform locking, the locking members are always connected simultaneously by the connecting members, so that the locking members are always engaged simultaneously. The lock member moves to the lock region, and the movement of the plurality of lock members does not vary.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to an embodiment shown in the drawings. As shown in FIG. 2, a rotary tool shown in the figure includes a sun gear 31 fixed to an output shaft 20 of a motor 2 and a gear case. 6, a planetary mechanism comprising an internal gear 33 fixed to the inner surface, a plurality of planetary gears 32 meshing with both of them, and a carrier 34 having a shaft 35 for supporting each planetary gear 32, as a reduction means, In this planetary mechanism, the carrier 34 and the output shaft 7 having the chuck 8 are arranged coaxially in the axial direction. In the drawing, reference numeral 60 denotes a motor mount, 61 denotes a sliding bearing for receiving the output shaft 7, 62 denotes a retaining ring, and 63, 64, and 65 denote steel balls and retainers constituting a thrust bearing.

As shown in FIG. 1, a plurality of projections 70 project radially and at equal intervals from the outer peripheral surface of the output shaft 7 on the carrier 34 side. A ring body 51 surrounding the outer periphery of the projection 70 is fixed to the inner surface of the gear case 6. And, on the end face of the carrier 34,
A plurality of projections 36 projecting in the axial direction and located in a space between the inner peripheral surface of the ring body 51 and the outer peripheral surface of the output shaft 7 are provided. The projections 36 are formed so that the same number as the projections 70 are formed at equal intervals in the circumferential direction and are located between the projections 70 of the output shaft 7, that is, the projections 3.
The protrusion 6 and the protrusion 70 are arranged at intervals in the circumferential direction, and the two protrusions 36 and 70 form a rotational power transmission connecting portion having a play at a predetermined angle in the rotational direction.

Here, the projection 70 on the output shaft 7
The outer peripheral surfaces on both sides of the inclined surface 7 on which the projection 70 side becomes lower, respectively.
Therefore, wedge-shaped spaces having different inclination directions are formed between the outer peripheral surface and the inner peripheral surface of the ring body 51 on both sides of the projection 70. In these two types of wedge-shaped spaces provided between the protrusion 36 and the protrusion 70 of the carrier 34, respectively, roller-shaped lock members 50a and 50b are disposed to form the lock means 5. . The lock member 50a disposed in the wedge-shaped space inclined in one direction is for locking in one direction, and the lock member 50b disposed in the wedge-shaped space inclined in the other direction is for locking in another direction. The diameters of the lock members 50a and 50b are smaller than the height of the portion of the wedge-shaped space on the side of the protrusion 70 and the protrusion 3
The lock members 50a and 50b are in a floating state when located on the protrusion 70 side because they are larger than the height of the portion on the 6 side. The output shaft 7 is locked by being engaged with the peripheral surface.

The lock members 50a, 50b
3 are provided in the illustrated example, but as shown in FIG. 3, they are radially inserted into a shaft hole formed in the lock member 50 a at each end, and the lock member 50 a Are connected to each other by a connecting body 9a having a shaft portion 91 for rotatably supporting the lock member 50, and the locking members 50b are also connected to each other by a connecting body 9b.

FIG. 7 shows the appearance of the rotary tool, in which 11 is a switch handle, 12 is a rotation direction switching handle, and 13 is a power pack. Next, the operation will be described. Now, if the motor 2 is rotated in one direction, the projection 36 of the carrier 34 in the planetary reduction mechanism presses the projection 70 of the output shaft 7 via the lock member 50b as shown in FIG. Rotate. At this time, a pair of lock members 50a, 50b located in the wedge-shaped space on both sides of the projection 70
Of these, the lock member 50b is positioned in the floating region in the wedge-shaped space portion by being pushed by the projection 36, that is, the portion near the protrusion 70, and the lock member 50a is positioned in the floating region in the wedge-shaped space portion due to its inertia. ,
Therefore, the lock members 50a and 50b do not hinder the rotation of the output shaft 7.

In particular, here, the projection 70 and the projection 36 have a substantially sector shape in which the width on the outer peripheral side is wider than the width on the inner peripheral side, and the difference is larger than the difference caused by the difference in the radial position. Therefore, the projections 36 and 70 generate a force for pressing the lock members 50 a and 50 b, which are both roller-shaped, against the outer peripheral surface of the output shaft 7.
There is no loss of force due to 50b contacting the inner peripheral surface of ring body 51.

When the rotation direction of the motor 2 is reversed, FIG.
As shown in FIG.
The power is transmitted to the output shaft 7 through the first and second shafts to rotate the output shaft 7. At this time, the two lock members 50a, 50
Since b is located on the floating region side in the wedge-shaped space, no lock is made. Then, if the main body 1 is rotated in the tightening direction around the axis of the output shaft 7 to perform manual tightening with the motor 2 stopped, the main body 1, that is, the ring body 51 and the output shaft 7 are connected to each other. As shown in FIG.
While the lock member 50a keeps its position in the floating region near the projection 70, the lock member 50a separates from the projection 70 by the rolling caused by the relative rotation and moves to the biting portion side in the wedge-shaped space portion. 51 and the output shaft 7 are integrated. That is, the free rotation of the output shaft 7 is controlled by the locking member 50a.
As a result, it is locked and rotates with the main body 1, and the screws and nuts can be manually tightened. The transition to the locked state is automatically made as described above. Further, since the plurality of lock members 50a are interconnected by the connecting body 9a, these lock members 50a are simultaneously locked. , And there is no possibility that only one lock member 50a participates in the lock.

When the main body 1 is turned in the opposite direction to loosen the screws and nuts, as shown in FIG.
b locks the output shaft 7 and enables hand return. In addition, since the plurality of lock members 50b are connected to each other by the connecting body 9b, all the lock members
0b simultaneously shifts to the locked state. If the motor 2 is rotated again while being locked by the lock members 50a and 50b, the projection 70 approaches the lock members 50a and 50b by the rotation of the output shaft 7 and locks. Lock member 5 which was in the biting position for
In order to return Oa and 50b to the floating region in the wedge-shaped space portion, or to push back the lock members 50a and 50b in the engagement position where the protrusion 36 of the carrier 34 is in the wedge-shaped space portion, the lock is released. Done automatically. The projection 36 is a power transmission member and also serves as a release member.

[0019]

As described above, according to the present invention, since a plurality of locking members respectively arranged in a plurality of wedge-shaped spaces are connected by a connecting member, the plurality of locking members are connected to the wedge-shaped spaces. When the lock member is moved to the engagement region side to perform locking, each lock member always moves to the engagement region at the same time, and there is no variation in the movement of the plurality of lock members. It is possible to increase reliability and prevent damage due to lock failure.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of one embodiment, showing a release state during forward rotation.

FIG. 2 is a longitudinal sectional view of the same.

FIG. 3 is an exploded perspective view of the connecting member and the lock member.

FIG. 4 is a sectional view showing a release state at the time of reverse rotation of the above.

FIG. 5 is a cross-sectional view showing a locked state when the same is manually tightened.

FIG. 6 is a cross-sectional view showing a locked state at the time of hand return according to the first embodiment.

FIG. 7 is a side view showing the appearance.

FIG. 8 is a cross-sectional view showing a lock failure state of a conventional example.

[Explanation of symbols]

 7 Output shaft 9a, 9b Connecting body 36 Projection 50a, 50b Lock member 51 Ring body 70 Projection

Claims (2)

(57) [Claims] 1. A non-rotatable ring which is provided with a power transmission connecting portion which is connected to an input shaft side member and an output shaft side member located coaxially with a play within a predetermined angle, and surrounds the output shaft side member. A wedge-shaped space is formed between the inner peripheral surface of the body and the outer peripheral surface of the output shaft side member to allow the lock member to bite and play, and the input shaft side member is provided with the lock member in a floating region in the wedge-shaped space portion. A rotary tool having a release member for pushing out to the side, wherein a plurality of lock members respectively arranged in a plurality of wedge-shaped spaces are connected by a connecting body. 2. Two types of wedge-shaped spaces whose inclination directions are opposite to each other are provided between the output shaft side member and the ring body.
One of the two types of wedge-shaped spaces is provided with a lock member for normal rotation lock, and the other is provided with a member for reverse rotation lock. 2. The rotating tool according to claim 1, wherein the rotating tools are connected by different connecting bodies.