JP2525111B2 - Torque Wrench - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque wrench that shock-rotates a spindle under the action of high fluid pressure.

[0002]

2. Description of the Related Art A torque wrench of this type is known in which a spindle 109 is fitted in an eccentric cavity 118 filled with a fluid in a rotating case 107 as shown in FIG. No. 1-29012). The spindle 109 is provided with two blades 110 and 111 which are urged outward in the radial direction by a spring (not shown) so as to be retractable, and lands (having a sealing surface) 127 and 128 are provided on the outer peripheral surface. Has been. On the inner peripheral surface of the rotating case 107, four lands 137, 139,
141 and 143 are provided. During operation, by rotating the rotating case with an air motor (not shown), sliding contact between the blade and the land causes the cavity 1
By partitioning 18 intermittently, a high fluid pressure is applied to one side of the spindle 109 and the blades 110 and 111.
As a result, the spindle 109 is shockedly rotated,
It is possible to tighten bolts and nuts.

Two blades 11 are attached to the spindle 109.
When 0, 111 are provided, there is an advantage that the shocking torque (striking) can be increased as compared with the case of one sheet. However, in the case of simply using two sheets, the blow of the rotating case 107 occurs twice per one rotation, which increases the load on the air motor. In order to avoid this, in the above example, the rotating case 10
The lands 141 and 143 of No. 7 are arranged slightly displaced from the minor axis L of the cavity 118 (the lands 127 and 128 of the spindle 109 are also displaced by the same amount). According to this arrangement, the lands 141 and 143 of the rotating case 107 and the lands 12 of the spindle 109 are rotated when the rotating case 107 is further rotated half a turn after the impact is generated (state of FIG. 6).
A gap δ in the circumferential direction is formed between the gap and 7,128. As a result, the impact at the time of half rotation is eliminated, and
You get 1 hit per revolution.

[0004]

However, the torque wrench described above has the lands 141, 14 of the rotating case 107.
Since the positions of the lands 127 and 128 of the spindle 3 and the spindle 109 are delicate, machining accuracy and assembly accuracy are strictly required. Therefore, there is a problem that it is difficult to manufacture.

Therefore, an object of the present invention is to provide a torque wrench which can obtain a single impact on the spindle per one rotation of the rotating case and which can be easily manufactured.

[0006]

To achieve the above object, the present invention comprises a rotating case having a substantially cylindrical shape and a chamber having an eyebrow cross section which is filled with a fluid. The rotating case is provided in the chamber of the rotating case. , A spindle rotatable around an axis is fitted, and is urged radially outward by a spring on a plane passing through the axis of the spindle, and the radial position by the inner peripheral surface of the chamber. The first and second blades are regulated so that the rotation of the rotating case causes a high fluid pressure to be intermittently applied to one surface of the spindle and the blade so as to shockly rotate the spindle. In the torque wrench, one side of the outer peripheral surface of the spindle is partitioned by the first and second blades.
In addition to providing the individual lands, a spring is urged outward in the radial direction on the other side of the outer peripheral surface, and the land is locked by an annular spindle holding portion provided on the end surface of the rotating case for a specific rotation. A third blade is provided so that the position in the radial direction does not exceed the outer peripheral surface when the rotation case is other than the corner. The third blade is provided on the inner peripheral surface of the chamber of the rotary case, and the rotary case is attached to the spindle. When the rotation angle reaches the specific rotation angle, the land of the spindle, the three lands that are in sliding contact with the first and second blades, respectively, and the third blade that opposes the third blade at a position radially separated from the outer peripheral surface of the spindle. An additional land is provided, and the spindle holding portion on the end surface of the rotating case is provided on the third blade when the rotating case reaches the specific rotation angle with respect to the spindle. By allowing the radially outward movement is characterized by providing an eccentric portion for sliding contact with said additional land.

[0007]

When the rotary case rotates and reaches a specific rotation angle with respect to the spindle, the three lands in the chamber of the rotary case are brought into sliding contact with the lands of the spindle and the first and second blades, respectively. At the same time, the additional land in the chamber faces the third blade at a position spaced from the outer peripheral surface of the spindle in the radial direction. At this specific rotation angle, the third blade is allowed to move outward in the radial direction by the eccentric portion provided on the spindle holding portion on the end surface of the rotating case, and is brought into sliding contact with the additional land. Therefore, the flow of the fluid in the chamber is blocked and the fluid pressure instantaneously rises. As a result, a large force is applied to the first and second blades, and the spindle receives a shocking torque (impact). ) Occurs. After the occurrence of this impact, when the rotary case further rotates half a turn, the land on the rotary case side and the first and second blades on the spindle side come into sliding contact again.
At this time, the position of the third blade in the radial direction is regulated so as not to cross the outer peripheral surface of the spindle by being locked by the spindle holding portion. As a result, a radial gap is created between the third blade and the land on the rotating case side (the one that comes to a position facing the third blade). At the same time, at a location on the opposite side of the axis, a radial gap is created between the land of the spindle and the additional land on the liner side facing the spindle land. It is because it is provided in the separated position.) As a result, the fluid in the chamber flows through the gap without being blocked. Therefore, after the impact occurs, when the rotating case makes a half rotation,
The spindle is not hit. That is, with this torque wrench, the impact is generated only once per one rotation of the rotating case. Therefore, a large load is not applied to a drive unit such as an air motor for rotating the rotating case.

Moreover, the four lands on the rotating case side may be provided on the inner peripheral surface of the chamber at an angle of 90 degrees.
That is, unlike the conventional structure shown in FIG. 6, it is not necessary to perform delicate positioning when processing the land. Therefore, it is easily manufactured.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The torque wrench of the present invention will be described in detail below with reference to the embodiments shown in the drawings.

As shown in FIG. 1, this torque wrench is
An air motor unit 1 housed in a casing 3 and a pulse generation unit 2 are provided. The pulse generator 2 includes a casing 5
A housing 6 housed inside, a liner 7 as a rotating case, a spindle 9, a first blade 10,
The second blade 11 and the third blade 60 shown in FIG. 2 are roughly configured (FIG. 2 shows a state in which the liner 7 and the spindle 9 are rotated 90 degrees with respect to FIG. 1). .

The recess 1 of the rotor 13 of the air motor unit 1
The convex portion 14a of the top cap 14 is fitted into and held by 3a. Outer end surface 14b of the top cap 14
, One end surface 7a of the liner 7 is brought into contact with the bottom cap 15 and the other end surface 7b of the liner 7 is brought into contact with the bottom cap 15 to form an integral body.
The liner 7 and the bottom cap 15 are fitted into the housing 6. Further, the female screw 6 of the housing 6
The male screw 17a of the housing nut 17 is screwed into a and tightened, so that the top cap 14, the liner 7 and the bottom cap 1 are formed by the radial convex portion 6b of the end surface of the housing 6 and the housing nut 17.
5 is fixed. Therefore, by supplying air to the air motor unit 1 to drive the rotor 13,
The liner 7 is rotated with respect to the casing 5.

Further, one end 9a of the spindle 9 is rotatably fitted in the central recess 14c of the top cap 14, and the other end 9b of the spindle 9 is rotatably attached to the cylindrical part 15a of the bottom cap 15. Is fitted to.
That is, the spindle 9 is held by the central concave portion 14c as the spindle holding portion and the cylindrical portion 15a with the axis of the liner 7 being the same. Then, by supplying air to the air motor section 1 to drive the rotor 13, the spindle 9 is shockedly rotated by the pulse generating section 2 as described later. The tip of the spindle 9 is projected to the outside of the casing 5 to connect a fastening tool or the like.

As shown in FIG. 4 (a), the liner 7 axially penetrates an oil-storing cavity 18 having a cocoon-shaped cross section, and the cavity 18 is positioned relative to the axis of the liner 7. It is composed of a cylindrical chamber 18a having a center that is eccentric in one direction, and a cylindrical chamber 18b having a center that is symmetrical with respect to the axis of the liner 7 at the center of the chamber 18a. The spindle 9 fitted in the cavity 18 has the first blade 10 and the second blade 10 which are urged radially outward by parallel springs 19 and 21 (see FIG. 1).
Blade 11 is provided. The blades 10 and 11
The blades 10 and 11 move in and out of the spindle 9 as the tips of the blades rotate on the arcs 23 and 25 of the chamber 18a and the chamber 18b. Further, a third blade 60 is provided on one side of the outer peripheral surface 30 of the spindle 9 which is partitioned by the blades 10 and 11. As shown in FIG. 2, the third blade 60 is biased radially outward by springs 61 and 62. A pair of pins 63, 63 are provided on the top cap 14 side and the bottom cap 15 side of the third blade 60.
Reference numerals 3 and 63 are engaged with the central recess 14c of the top cap and the cylindrical portion 15a of the bottom cap 15, respectively. As a result, as shown in FIGS. 4 (a) and (b) to FIGS. 5 (a) and (b), the third blade 6 does not rotate at the normal rotation angle of the liner 7.
The tip of 0 is regulated so as not to exceed the outer peripheral surface 30 of the spindle 9. However, the central concave portion 14c of the top cap and the cylindrical portion 15a of the bottom cap 15 are provided with an eccentric portion 65 curved outward in the radial direction. Therefore, the liner 7 has a specific rotation angle (state of FIG. 3 (a)).
When the third blade 60 comes in, the outward movement of the third blade 60 in the radial direction is allowed. A land 27 is provided on the spindle 9 by cutting out a part of the outer peripheral surface 30 on the side opposite to the blade 60. The groove 26 for the blades 10 and 11 and the groove 66 for the blade 60 are formed along a plane passing through the axis of the spindle 9.

As shown in FIG. 3 (a), the inner wall of the chamber 18a and the chamber 1 are formed on the inner peripheral surface of the cavity 18 in the liner 7.
A land 35 is provided at a position where the inner wall of 8b intersects with the land 27 of the spindle 9 and, on the other hand, when the land 27 and the land 35 are in sliding contact, the land 35 is opposite to the axial center of the land 35. The spindle outer peripheral surface 3
Facing the blade 60 with a radial separation from 0
An additional land 37 (which actually makes sliding contact) is provided. The inner surfaces of the lands 35 and 37 of the liner 7 are formed in an arc having the same curvature as the outer peripheral surface 30 of the spindle 9. Therefore, the land 27 of the spindle 9 and the blade 6
0 and the lands 35 and 37 of the liner 7 are in close contact with each other and slidably contact with each other to seal the oil in the chambers 18a and 18b. Also,
When the land 27, the blade 60 and the lands 35, 37 are in sliding contact with each other, the blades 10, 11 move into the chamber 18a.
Land 3 at the position where it makes sliding contact with the inner wall of the
9, 41 are provided. Therefore, when the liner 7 reaches the specific rotation angle shown in FIG. 3A with respect to the spindle 9, the blades 10 and 11 and the lands 39 and 41 are brought into close contact with each other and slidably contact with each other, so that the land 27 and the blade 60 are contacted with each other. Land 35,
By closely contacting with 37 and 38 and slidingly contacting each other, the chamber 18
Each of a and 18b is divided. Further, the inner wall of the liner 7 is provided with recesses 48, 49, 50 and 51 for moving the oil inside the cavity. 53 is a relief valve.

The torque wrench having the above construction operates as follows.

First, when there is no load on the spindle 9,
The spindle 9 rotates together with the liner 7 and the like due to resistance between the inner peripheral surface of the cavity of the liner 7 and the blades 10 and 11. When the spindle 9 is loaded, that is, when the bolts are tightened, the spindle 9 tries to stop, but the liner 7 is
The air motor unit 1 shown in FIG. 2 keeps rotating.

One cycle of pulse generation in one rotation of the liner 7 will be described with reference to FIGS.

FIGS. 5 (a) and 5 (b) show a state before a pulse is generated. The liner 7 rotates in the direction of the arrow, and the land 35 of the liner 7 extends from the tip of the blade 11 of the spindle 9 to the land 27. The lands 37 of 7 approach the blade 60 from the tip of the blade 10 of the spindle 9, respectively. At this time, the oil in the chambers 18a and 18b of the cavity 18 of the liner 7 passes through the recesses 49 and 51 on the inner peripheral surface of the liner, respectively, and moves as shown by the arrow in FIG. At this time, in the blade 60, the pin 63 of the blade 60 has the central recess 14c (and the bottom cap 1) of the top cap 14.
Since it is locked to the cylindrical portion 15a) of No. 5, it is recessed inside the spindle outer peripheral surface 30.

In FIG. 3 (a), the liner 7 is further rotated and the lands 35, 39, 41 of the liner 7 are rotated by the spindle 9
The land 27 and the tips of the blades 10 and 11 are completely in contact with each other. When the liner 7 reaches this rotation angle with respect to the spindle 9, the blade 60
The eccentric portion 65 allows the outward movement in the radial direction. Then, it comes into contact with the land 37 of the liner 7 located at the opposite position. At this time, since the above-described oil flow is suddenly stopped in the chambers 18a and 18b, a large force is momentarily applied to the upper side surface of the blade 10 and the lower side surface of the blade 11 in the figure due to the inertia of the oil. As a result, a shocking torque (striking) is generated in the spindle 9, and the bolt or the like can be tightened.

After the impact is generated, the liner 7 is further rotated and the state shown in FIG. 3 (b) is changed to the state shown in FIG. 4 (a). FIG.
In (a), the lands 35, 37 of the liner 7 are the blades 10,
11 shows a state in which the tip 11 is completely contacted. At this time, the flow of oil in the cavity 18 is suddenly blocked, and the chamber 18 of the two chambers partitioned by the spindle 9 is
The oil pressures on the left side in the figure of b and the right side of the chamber 18a in the figure instantaneously rise (pulse generation). However, since the two blades 10 and 11 for transmitting the oil pressure to the spindle are submerged in the spindle 9 by the inner wall of the liner 7 at this time, the oil pressure is not transmitted to the spindle 9 and the spindle 9 Does not rotate.

FIG. 4 (b) shows a state further rotated by 90 degrees from the state of FIG. 4 (a). This state is the opposite state in which the tightening torque is obtained by rotating 180 degrees from the state shown in FIG. 3A, and the lands 41 and 39 of the liner 7 are in sliding contact with the blades 10 and 11 on the spindle 9 side, respectively.
However, the pin 63 of the blade 60 is the top cap 14
Central recess 14c (and the cylindrical portion 1 of the bottom cap 15)
5a), it is immersed inside the spindle outer peripheral surface 30. As a result, a radial gap δ1 is formed between the blade 60 and the land 35 on the liner 7 side. At the same time, at the location opposite the axis, the spindle 9
A radial gap δ2 is formed between the land 27 of the liner 7 and the land 37 of the liner 7 located at a position opposite to the land 27.
(This is because the land 37 is provided at a position separated from the outer peripheral surface 30 of the spindle in the radial direction.). As a result, the oil in the chamber 18 is not blocked and
It flows through the gaps δ1 and δ2. Therefore, when the liner 7 makes a half rotation after the occurrence of the impact, the spindle 9 is not impacted. That is, with this torque wrench, the impact can be generated only once per one rotation of the liner 7. Therefore, in order to rotate the housing 6 and the liner 7 shown in FIGS. 1 and 2, a great burden is not applied to the air motor unit 1.

When the liner 7 is further rotated 90 degrees from the state shown in FIG. 4 (b) to the state shown in FIG. 5 (a),
A pulse is generated as in Fig. 4 (a), but the blade 1
Since 0 and 11 are immersed, the oil pressure is not transmitted to the spindle 9 and the spindle 9 does not rotate.

By repeating the above operation,
A large pulse-shaped torque can be applied to the spindle 9 by the two blades 10 and 11, and the bolts and nuts can be tightened via a tightening tool such as a socket.

Moreover, the four lands 35, 37, 39, 41 on the inner peripheral surface of the liner 7 may be provided on the inner peripheral surface of the chamber 18 at an angle of 90 degrees. That is, unlike the conventional structure shown in FIG. 6, it is not necessary to perform delicate positioning when processing the land. Therefore, this torque wrench can be easily manufactured.

[0025]

As is apparent from the above, the torque wrench of the present invention is provided with one land on one side of the outer peripheral surface of the spindle which is partitioned by the first and second blades, and the outer periphery is The spring is urged outward in the radial direction by a spring on the other side of the surface, and is locked by an annular spindle holding portion provided on the end surface of the rotating case, and the radial position is set at a value other than a specific rotation angle. Is provided so that it does not exceed the outer peripheral surface, and the inner peripheral surface of the rotating case has a land of the spindle when the rotating case reaches the specific rotation angle with respect to the spindle. The rotating case is provided with three lands that are in sliding contact with the first and second blades, respectively, and an additional land that faces the third blade at a position radially separated from the outer peripheral surface of the spindle. In the spindle holding portion of the end face,
An eccentric portion is provided to allow the third blade to move outward in the radial direction when the rotating case comes to the specific rotation angle with respect to the spindle, and to make sliding contact with the additional land. The land on the spindle side, the first, second and third blades, and the four lands on the rotating case side are slidably contacted with each other at a specific rotation angle to give a shocking torque (striking) to the spindle. it can. Moreover, after the impact has occurred, when the rotary case further rotates halfway with respect to the spindle, a gap is formed between the land on the spindle side, the third blade, and the opposing land on the rotary case side. It is possible to prevent hitting. Therefore, it is possible to obtain one impact on the spindle per one rotation of the rotating case, and to generate a pulsed torque larger than that in the case of one blade without increasing the power of the drive unit that drives the rotating case. Obtainable.

Moreover, the four lands on the inner peripheral surface of the rotating case may be provided on the inner peripheral surface of the chamber at an angle of 90 degrees, and delicate positioning is not required. Therefore, this torque wrench can be easily manufactured.

[Brief description of drawings]

FIG. 1 is a diagram showing a pulse generator of a torque wrench according to an embodiment of the present invention.

FIG. 2 is a diagram showing a pulse generator of the torque wrench according to the embodiment of the present invention.

FIG. 3 is a diagram showing a cross section of the pulse generating section in an operating state.

FIG. 4 is a view showing a cross section of the pulse generating section in an operating state.

FIG. 5 is a diagram showing a cross section of the pulse generating section in an operating state.

FIG. 6 is a view showing a cross section of a conventional torque wrench.

[Explanation of symbols]

 1 Air Motor 2 Pulse Generator 7 Liner 9 Spindle 10,11,60 Blade 27,35,37,39,41 Land

Claims (1)

(57) [Claims] 1. A rotating case having a substantially cylindrical shape and a chamber having an eyebrow cross section filled with a fluid is provided, and a spindle rotatable about an axis is fitted in the chamber of the rotating case. A first blade and a second blade, which are biased radially outward by a spring and whose radial position is restricted by the inner peripheral surface of the chamber, are arranged on a plane passing through the axis of the spindle. A torque wrench adapted to intermittently apply a high fluid pressure to one side of the spindle and the blade by the rotation of the rotating case to impactly rotate the spindle. One land is provided on one side partitioned by the second blade, and the other side of the outer peripheral surface is biased radially outward by a spring and is provided on the end surface of the rotating case. A third blade is provided which is locked to the annular spindle holding portion and is regulated so that the radial position does not exceed the outer peripheral surface except at a specific rotation angle. On the inner peripheral surface of the spindle, the three lands that respectively slide on the land of the spindle, the first blade, and the second blade when the rotation case reaches the specific rotation angle with respect to the spindle, and from the outer peripheral surface of the spindle. An additional land facing the third blade is provided at a position separated in the radial direction, and the rotating case comes to the specific rotation angle with respect to the spindle in the spindle holding portion of the end surface of the rotating case. At this time, the torque wrench is provided with an eccentric portion that allows the outward movement of the third blade in the radial direction and makes sliding contact with the additional land.