JPS5852792B2 - Hydraulic torque wrench torque regulating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a torque regulating device for a hydraulic torque wrench.

Regarding torque wrenches, which are general pneumatic tools,
The rotational force of the rotor is decelerated and a striking force is generated mechanically, and this striking force is used to convert it into a desired torque.

Therefore, the mechanical impact noise causes noise pollution, and there is a risk of getting white wax due to the vibration.

For this purpose, a liner having an eccentric inner hole is driven by a rotor rotated by pressurized air, the inner hole is divided into two chambers by a main shaft equipped with vanes, and oil is sealed in the divided chamber. It is known to use a hydraulic torque generator that generates torque by this (
For example, Special Publication No. 39-10644).

However, the torque regulating means in this system only allows the high pressure oil in the chamber where the sealing occurs to be communicated with the low pressure chamber on the opposite side via the relief valve, thereby continuing the rotation.

Another known method is to change the engagement length of the clutch and cut off the supply air when a predetermined torque is reached.
For example, in the case of impact torque transmission using an impact wrench (Japanese Patent Publication No. 36-500), there are problems such as generation of noise and poor wear resistance.

In view of this, the present invention proposes a device that easily regulates the generated torque in a hydraulic torque wrench that generates impact force and torque using hydraulic pressure from the rotational force of a rotor rotated by high-pressure air. be.

The present invention will be explained below based on examples.

In the figure, 1 is the main body of the torque wrench, which is rotated by the main valve 2 that supplies or stops the supply of high-pressure air into the main body, and the high-pressure air supplied from the main valve 2 via the control valve mechanism 3. The rotor 4 is equipped with a hydraulic torque generating device 5 that intermittently generates a predetermined torque using a hydraulic pressure generating mechanism sealed in a liner using the rotational force of the rotor.

The hydraulic torque generating device 5 has a rotatable liner 8 whose inner diameter is eccentric with respect to the main shaft 7 in a main body casing 6, and this liner is filled and sealed with hydraulic oil for generating torque. A blade 9 is provided on the main shaft 7 so as to always protrude by means of a spring S, and is slidably provided in a groove provided in the radial direction of the main shaft, and the tip of the blade 9 and the outer end surface 7a on the side opposite to the blade mounting portion of the main shaft. The distance between the liner and the inner diameter of the liner is adjusted so that the inner diameter of the liner is in contact with the inner surface of the eccentric small diameter part of the inner diameter of the liner.

That is, when the main shaft 7 is in a vertical state as shown in the operation diagram B in FIG. 3, the center of the liner chamber is vertically below the rotation axis (
Only when the liner chamber is in the lowermost position), the blade 9 and the side opposite to the blade mounting portion of the main shaft 7, that is, the outer end surface 7a, are in contact with each other, and the liner chamber is divided into two left and right chambers.

In this state, when the liner 8 rotates to the left of the arrow, the volume of the left chamber changes in the compression direction and the right chamber changes in the expansion direction, creating a confinement pressure in the hydraulic oil in the left chamber, and this pressure is applied to the sides of the main shaft 7 and the blades 9, but the center of rotation of the main shaft 7 is above the center of the liner chamber, so the main shaft I is rotated to the left along with the liner 8.

However, this sealing of the hydraulic oil is only in the position shown in Figure 3B above, and it is clear from the drawings that the liner chamber is in a position other than the lowest position above, before impact as shown in Figure A and after impact as shown in Figure C. As shown in the figure, the left and right chambers of the main shaft 7 are communicated with each other, and no rotational torque is generated on the main shaft 7.

Now, the rotational torque applied to the main shaft 7 is used to tighten bolts, for example, through a wrench attached to the tip of the main shaft 7.

At this time, if the torque generation detection mechanism and its control mechanism are released, the rotor continues to rotate with the continuously supplied high-pressure air, and when the bolt tightening is completed, the hydraulic torque generator generates the set torque. This results in the generation of a huge torque on the main shaft.

In the present invention, the hydraulic pressure generated in the liner chamber on the high pressure chamber side is detected, and when the main shaft reaches a predetermined torque, the air supply to the rotor is stopped even if the main valve is ON, and the entire torque wrench is stopped. That's how I did it.

This torque regulating device passes through the axis of the rotor 4 and is connected to the main shaft 7.
A slidable rod 10 with one end inserted therein, a control valve mechanism 3 provided in an air supply passage leading from the main valve 2 to the rotor 4, and the control valve mechanism 3 which is swung by the sliding of the rod 10. Lever 1 that operates in the closing direction
1 is the main subject.

The rod insertion hole of the main shaft 7 and the chamber that generates the confinement pressure are communicated via the main shaft 70 blade insertion groove.

As a result, the rod 10 is moved by the above-mentioned confinement pressure, and the lever 11 is swung about the central portion to operate the control valve mechanism 3 and shut off the air supply passage.

The confinement pressure for sliding this rod 10, that is, the set pressure of the torque, can be adjusted.

For example, on the arm facing the rod 10 of the lever 11,
A spring S is provided to bias the rod 10 in the pressing direction, and the spring pressure can be adjusted using an adjustment nut or the like.

This prevents the rod 10 from sliding if the confinement pressure does not reach the set value.

For example, a well-known shut-off valve is used as the control valve mechanism 3.

As shown in FIG. 2, although the slide valve 12 is normally locked by the lever 11 and opens the air supply passage, the lever 12
1 is released, supply air pressure is applied to the head 7 flange of the sliding valve 12, causing the sliding shaft 12 to move against the retaining spring, thereby blocking the passage.

This interruption continues as long as pressurized air is supplied.

Next, by closing the main valve 2, the sliding valve 12 moves back due to the holding spring, opens the passage, and closes the lever 11.
engagement is permitted.

Note that the limit switch may be actuated by the rod 10, and the control valve mechanism 3 may be an electromagnetic valve to electrically shut off the passage, or the oil pressure on the high pressure side of the liner chamber may be used to operate the limit switch without using a rod or the like. It is also possible to operate a direct control valve mechanism.

According to the present invention, in a torque wrench that converts the rotational force of the rotor into rotational torque for the main shaft using hydraulic oil filled and sealed in a liner chamber, the high-pressure oil pressure of this hydraulic torque generator is used. When the pressure exceeds the set pressure, the oil pressure stops the air supply to the rotor chamber, so it generates less noise and vibration than conventional torque wrenches, and also reliably generates large torque. It has the advantage that setting and adjustment of the torque is simple and reliable.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view showing an embodiment of the torque wrench of the present invention, Fig. 2 is an explanatory view of the control valve mechanism, and Fig. 3 is an explanatory view of the hydraulic torque generator. C shows the cross section at the time of impact, and C shows the cross section after impact. 1...Main body, 2...Main valve, 3
... Control valve mechanism, 4 ... Rotor,
5...Hydraulic torque generator, 6...
Main body casing, 7...Main shaft, 8...
Liner, 9...Blade, 10...Rod, 11...Lever S...Spring.

Claims (1)

[Claims] 1 A rotor rotated by high-pressure air and a hydraulic torque generator driven by the rotor, the hydraulic torque generator having a liner chamber driven by the rotor and eccentric to the rotation axis. a liner having
It consists of a main shaft connected to a wrench at one end and equipped with vanes that are inserted into the liner chamber concentrically with the rotating shaft and biased in the radial direction.The liner chamber is filled with hydraulic oil and sealed, and the liner When the liner chamber is divided into two by the blade and the opposite side of the main shaft from where the blade is attached due to rotation, oil is trapped in one chamber, applying rotational torque to the main shaft, and the rotor center shaft is penetrates the rod that is pressed and transferred by the sealed hydraulic pressure,
The high-pressure air supply circuit for the rotor includes a control valve mechanism for shutting off the air supply, movement of the rod actuates the control valve mechanism to cut off the air supply, and an adjustable spring restricts movement of the rod. A torque regulating device for a hydraulic torque wrench, characterized by comprising: