JPH05253858A - Hydraulic torque wrench - Google Patents

Abstract

PURPOSE:To provide constitution by which one time striking torque can be obtained by one rotation of an oil cylinder in a hydraulic torque wrench by simple processing works. CONSTITUTION:A flat cam section 16 which is rotated integrally with an oil cylinder 3, is provided for the hole section 14 of a main shaft within the oil cylinder 3. The cam section 16 is provided with a recessed intrusive section 22, when the cam section 16 is rotated, the leg section 25a of a first blade 25 is decoupled from the recessed intrusive section 22 in the rotating direction, and the leg section 26a of a second blade 26 follows the cam section. A high pressure and a low pressure room are generated at the both sides of each projected blade 25 and 26 under s specified phase, so that striking torque is thereby generated. Under a state that phase is different by 180 from the aforesaid specified phase, the leg section 25a of the first blade 25 is coupled in the recessed intrusive section 22 of the cam section 16, so that no pressure difference exists at the both sides of each blade.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic torque wrench used for tightening fasteners such as bolts and nuts.

[0002]

2. Description of the Related Art A conventional hydraulic torque wrench disclosed in Japanese Unexamined Patent Publication No. 64-45582 is provided in (a) an oil cylinder rotatably driven by a rotor and (b) rotatably in the oil cylinder. And a cam that is housed in a hole formed in (c) the main shaft and is interlocked with and connected to an oil cylinder, and (d) is provided at two positions that are approximately 180 degrees out of phase with each other in the circumferential direction of the main shaft. A pair of blades, (e) a pair of main shaft side seal surfaces formed on the outer peripheral surface of the main shaft having a phase difference of about 90 degrees from each blade in the circumferential direction, and (f) each main shaft side at a specific phase A pair of first seal surfaces formed on the inner peripheral surface of the oil cylinder so as to be in close contact with the seal surfaces, and (g) oil tightly on the projecting end surfaces of the blades extruded by the cam at the specific phase. To be close in the state A pair of second sealing surfaces formed on the inner peripheral surface of the oil cylinder, and in a phase other than the specific phase, the through hole and the hole formed in the main shaft on both sides of the cam portion. The oil chambers on both sides of the first sealing surface are communicated with each other, or the oil chambers on both sides of each blade are communicated with each other via.

In this type of hydraulic torque wrench, with respect to one rotation of the oil cylinder, the oil chamber on one side of the blade becomes the high pressure chamber and the oil chamber on the other side becomes the low pressure chamber in the above-described specific phase, and the impact torque is given once. Therefore, a large impact torque can be obtained with a large rotational inertia of the oil cylinder.

[0004]

However, in the conventional hydraulic torque wrench, it is necessary to form a through hole in the main shaft with high processing accuracy, and therefore, there is a drawback in that the processing operation requires labor.

The present invention has been made to solve the above-mentioned conventional drawbacks, and an object thereof is to provide a structure for obtaining one impact torque for one rotation of an oil cylinder with high processing accuracy. The purpose of the present invention is to provide a hydraulic torque wrench that is easy to process and can be constructed at low cost by making it possible to obtain it without needing it.

[0006]

Therefore, the hydraulic torque wrench of the present invention includes an oil cylinder that is rotationally driven, a main shaft that is relatively rotatably provided in the oil cylinder, and a flat cam portion on both sides. Each is provided with a cylindrical shaft portion, a space is formed between the shaft portions, one shaft portion is connected to the oil cylinder, and the other shaft portion is supported by the main shaft so as to be relatively rotatable. In addition, the cam portion accommodates the rotating member housed in the hole formed in the main shaft, the recessed portion formed on one end side in the width direction of the cam portion, and 180 degrees with respect to each other in the circumferential direction of the main shaft. First and second blade insertion grooves, which are formed at two different phases and communicate with each other through the hole, and are housed in the first blade insertion groove, and when the cam portion rotates, the width direction thereof. At one end of the above A leg part that is fitted in and out in the rotational direction of the cam part and is imitated by the cam at the other end part in the width direction of the cam part, and the first part that can freely move in and out within a range that does not completely project from the first blade insertion groove A first blade having a blade body housed in a blade insertion groove, and a second blade insertion groove, housed in a second blade insertion groove, and copied to both one end and the other end in the width direction when the cam portion rotates. A second blade having a leg portion and a blade body housed in the second blade insertion groove so that the blade body can be retracted and retracted within a range that does not completely project from the second blade insertion groove, and 90 degrees in the circumferential direction from each blade. Or, it is formed on the inner peripheral surface of each of the oil cylinders so as to be in close contact with the pair of main shaft side seal surfaces at a specific phase and a pair of main shaft side seal surfaces formed on the outer peripheral surfaces having different phases by approximately 90 degrees. A pair of first sealing surfaces and the above-mentioned specification The in-phase extruded by one end and the other end in the width direction of the cam portion 1
And a pair of second sealing surfaces formed on the inner peripheral surface of the oil cylinder so as to contact the respective projecting end surfaces of the blade and the second blade.
In different phases, the leg portion of the first blade is fitted in the recessed portion so that the tip end surface of the first blade does not come into contact with the second seal surface.

[0007]

In the hydraulic torque wrench having this structure, the main shaft side seal surface and the first seal surface are in close contact with each other, and the projecting end surfaces of the first blade and the second blade contact the pair of second seal surfaces. In the specific phase, the oil chambers before and after each blade become a high-pressure chamber and a low-pressure chamber, which produces a striking torque. Further, in the phase shifted by 180 degrees from the specific phase, the first blade retreats into the first blade insertion groove because the leg portion of the first blade fits into the recessed portion of the cam portion, and the second blade The oil chamber at the rear of the blade and the oil chamber facing the end surface of the first blade communicate with each other through the second blade insertion groove, the space between the shaft portions, and the first blade insertion groove, so that the front and rear of the blade There is no pressure difference and no striking torque.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 1 is a wrench body, and a rotor 2 is rotatably provided at an upper rear portion of the wrench body 1. An oil cylinder 3 is rotatably provided above the front part of the wrench body 1. The oil cylinder 3 is connected to the rotor 2 so that the oil cylinder 3 is rotationally driven by the rotor 2. .. The grip portion 4 of the wrench body 1 changes the direction of air flow to the rotor 2, the air supply port 5, the valve lever 7 for operating the main valve 6 that opens and closes the air flow path from the air supply port 5 to the rotor. And a rotation switching lever 8 for switching the rotation direction of the rotor 2. The wrench body 1
A main shaft 9 is rotatably projected from the front end of the main shaft 9, and a mounting portion 10 is provided at the tip of the main shaft 9 for mounting various tools having different diameters in a replaceable manner.

As shown in FIG. 2, the oil cylinder 3 is constructed by integrally connecting a pair of front and rear end plates 12 and 13 to a cylindrical cylinder body 11. The rear end plate 13 is connected to the rotor 2 so as to rotate integrally therewith, and the front end plate 12 rotatably holds the main shaft 9.

A hole 14 is concentrically formed in a portion of the main shaft 9 located inside the cylinder body 11, and a rotary member 15 is inserted into the hole 14. As shown in a perspective view in FIG. 3, the rotating member 15 includes cylindrical shaft portions 17 and 18 on both sides sandwiching the flat cam portion 16, respectively.
One shaft 17 is rotatably supported by the front end of the hole 14, and the other shaft 18 is inserted into a holding hole 19 formed in the rear end plate 13. The key portion 20 provided on the other shaft portion 18 is engaged with the key hole 21 laid in the holding hole 19 in the rotational direction. A recess 22 is formed at the center of the cam portion 16 in the axial direction A and at one end of the cam portion 16 in the width direction B.

Further, as shown in FIG. 4, a first blade insertion groove 23 and a second blade insertion groove 24 are formed at two locations which are 180 degrees out of phase with each other in the circumferential direction of the main shaft 9, and these are formed. The insertion grooves 23, 24 are communicated with each other through the hole 14 corresponding to the space S between the shafts 17, 18.

A first blade 25 is housed in the first blade insertion groove 23, and a second blade 26 is housed in the second blade insertion groove 24. As shown in a perspective view in FIG. 3, the first blade 25 has a leg portion 25a and a blade body 25b, and the leg portion 25a is formed in a lateral width that can be inserted into and removed from the recessed portion 22 of the cam portion 16. ing. Therefore, when the cam portion 16 rotates, the leg portion 25a of the first blade 25 is inserted into and removed from the recessed portion 22 in the rotation direction X of the cam portion 16 at the one end portion 16a in the width direction B of the cam portion 16. When the cam portion 16 rotates and the leg portion 25a of the first blade 25 corresponds to the other end portion 16b of the cam portion 16 in the width direction B, a part of the blade body 25b remains inside the insertion groove 23. It projects from the insertion groove 23. On the other hand, the second
The blade 26 also has a leg portion 26 a and a blade body 26 b, but the lateral width of the leg portion 26 a of the second blade 26 is longer than the lateral width of the recess 22. Therefore, the leg portion 26a of the second blade 26 cannot be inserted into or removed from the recessed portion 22 even if the cam portion 16 rotates. Therefore, the cam portion 1
6 is rotated and the leg portion 26a of the second blade 26 is moved to the cam portion 1
6 corresponds to one end portion 16a and the other end portion 16b in the width direction B, a part of the blade body 26b protrudes from the insertion groove 24 while remaining inside the insertion groove 24.

As shown in FIGS. 4 to 6, main shaft side seal surfaces 27 and 28 are formed on the outer peripheral surface of the main shaft 9 with the phases different from each other by 90 degrees or approximately 90 degrees from the blades 25 and 26 in the circumferential direction. Has been done. Further, the cross-sectional shape of the inside of the seal body 11 is eyebrows, and the first seal surface 29, 30 and the second seal surface 31, 32 are formed on the inner peripheral surface of the seal body 11. The first seal surfaces 29, 30 are in oil-tight contact only with the main shaft side seal surfaces 27, 28,
The second sealing surfaces 31, 32 are in contact with the protruding end surfaces of the blades 25, 26.

According to the above construction, in the specific phase state shown in FIG. 4, the second blade 26 is pushed out by the one end portion 16a of the cam portion 16 in the width direction and the second blade 2 is pushed.
The protruding end surface of 6 contacts the second seal surface 32, and the other end portion 16b of the cam portion 16 in the width direction pushes out the first blade 25 so that the protruding end surface of the first blade 25 becomes the second
Contacting the sealing surface 31 and at the same time each of the first sealing surfaces 29,
The main shaft side sealing surfaces 27 and 28 are in close contact with 30. Therefore, the front and rear oil chambers of the blades 25 and 26 with respect to the rotation direction X of the oil cylinder 3 become the high pressure chamber H and the low pressure chamber L, and a striking torque is generated.

From the specific phase state of FIG. 4, the oil cylinder 3
Is rotated by 180 degrees, the leg portion 25a of the first blade 25 is fitted into the recessed portion 22 of the cam portion 16, so that the first blade 25 retracts into the insertion groove 23, as shown in FIG. It does not contact the second sealing surface 32. Then, the oil chamber R1 behind the second blade 26 (backward in the rotation direction of the oil cylinder 3) has an end surface of the first blade 25 through the second blade insertion groove 24, the space S, and the first blade insertion groove 23. Is communicated with the oil chamber R2. Therefore, the high pressure chamber and the low pressure chamber are not generated, and the striking torque is not generated. When the oil cylinder 3 is rotated by 90 degrees from the specific phase state of FIG. 4, the striking torque is not generated, as is clear from FIG.

[0016]

As described above, according to the hydraulic torque wrench of the present invention, one impact is generated for one rotation of the oil cylinder with respect to the main shaft. Since such a structure can be obtained without requiring high processing accuracy, it is possible to provide a torque wrench at low cost with a simple processing operation.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view showing an overall configuration of a hydraulic torque wrench according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of essential parts showing a specific phase state when the hydraulic torque wrench according to the embodiment of the present invention generates a striking torque.

FIG. 3 is a perspective view showing a rotating member and first and second blades.

FIG. 4 is an explanatory diagram of a specific phase state.

FIG. 5 is an explanatory diagram of a phase state when the phase is changed by 90 degrees from the specific phase state.

FIG. 6 is an explanatory diagram of a phase state when the phase is changed by 180 degrees from the specific phase state.

[Explanation of symbols]

 3 Oil Cylinder 9 Spindle 14 Hole 15 Rotating Member 16 Cam 16a One End of Cam 17 Shaft 18 Shaft 22 Recess 23 First Blade Insertion Groove 24 Second Blade Inserting Groove 25 First Blade 25a First Blade Leg portion 25b Blade body of first blade 26 Second blade 26a Leg portion of second blade 26b Blade body of second blade 27 Spindle side sealing surface 28 Spindle side sealing surface 29 First sealing surface 30 First sealing surface 31 Second Sealing surface 32 Second sealing surface S Space between shaft parts B Width direction of cam part R1 oil chamber R2 oil chamber

Claims (1)

[Claims] 1. An oil cylinder which is rotationally driven, a main shaft which is relatively rotatably provided in the oil cylinder, and cylindrical shaft parts which are respectively provided on both sides of a flat cam part, and these shafts are provided. A space is formed between the parts, one shaft part is connected to the oil cylinder, the other shaft part is rotatably supported by the main shaft, and the cam part is formed on the main shaft. The rotating member housed in the hole, the recess formed on the one end side in the width direction of the cam, and the recess formed in two positions 180 degrees out of phase with each other in the circumferential direction of the main shaft, and the hole First communicating with each other via a part
And a second blade insertion groove and a first blade insertion groove. When the cam portion is rotated, one end portion in the width direction of the cam portion is fitted into and removed from the recessed portion in the rotation direction of the cam portion, and the width of the cam portion is large. The other end in the direction includes a leg part that is imitated by the cam, and a blade body that is housed in the first blade insertion groove so that it can be retracted and retracted within a range that does not completely project from the first blade insertion groove. The blade, the leg portion housed in the second blade insertion groove, and imitated by both the one end portion and the other end portion in the width direction when the cam portion rotates, and the leg portion which does not completely project from the second blade insertion groove A second blade having a blade main body housed in a second blade insertion groove so as to be retractable within a range, and formed on an outer peripheral surface having a phase difference of 90 degrees or substantially 90 degrees from each blade in the circumferential direction. A pair of spindle side sealing surfaces and a specific position Phase, a pair of first seal surfaces formed on the inner peripheral surface of each oil cylinder so as to be in close contact with the main shaft side seal surface, and one end and the other end of the cam portion in the width direction at the specific phase. And a pair of second seal surfaces formed on the inner peripheral surface of the oil cylinder so as to contact the respective projecting end surfaces of the first blade and the second blade extruded by In the 180 degrees different phase,
A hydraulic torque wrench characterized in that the leg portion of the first blade is fitted into the recessed portion so that the tip end surface of the first blade does not come into contact with the second seal surface.