JPS5997853A - Automatic controller for clamping of torque wrench - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic tightening force control device for an air-driven torque wrench.

Air-operated torque wrenches used for tightening bolts, nuts, etc. are of the type that generate impact force using conventional mechanical methods and use this impact force to convert it into the desired torque. Alternatively, a type has been developed in which an intermittent increase in pressure is generated in the oil confinement area to apply an impulsive torque. Compared to the former type, the latter type generates much lower impact noise and vibration than the former type.
Since there is no resonance and the handling is good, it is necessary to set the tightening torque to prevent excessive tightening. Of course, even in the case of a general type (for example, the former type), it is preferable that the tightening torque can be set as specified.

The present invention provides a torque wrench in which when the tightening torque reaches a preset condition, the tightening is performed by activating a sensor using reaction force, thereby activating a stop valve provided in the air supply passage. It is an object of the present invention to provide a tightening control device that can perform proper tightening by inferring the air supply to the motor and stopping the tightening operation.

The present invention uses an air motor to perform tightening via a force generation mechanism.
C4fl? to activate the connection operation socket fc,
' The child is connected to the piston of the operating cylinder provided on the rear cover of the main body so that it engages with the main actuator only during air supply, and the operating piece is attached to the outer periphery via a reversing weight cam clutch so that the operating piece can be returned to its original position. A reciprocating stop valve is installed in the middle of the air supply passage of the air motor, and a notch is provided at the end of the valve stem of the stop valve. A stopper is pivotally provided adjacent to the stopper to keep the stop valve in the open state, and a tightening device is provided on the outside of the cover that engages with the protrusion of the operating piece to set the reversal operation position in multiple stages. is equipped with an adjustment handle for torque setting, and when the operation piece set by this adjustment handle tightens the output side of the lE tool due to reaction force, when the motor is reversed, the operation piece rotates together with the motor shaft and its attached protrusion By contacting the stopper with the stopper, the IL force of the valve stem is removed, the stop valve valve is transferred by supply pressure, and the tightening action is stopped by cutting off the air supply to the motor.
When the air supply stops, the stop 1 valve returns to the open state, and the friction clutch slave Uσ1 moves away from the main driver.

In case of "misfire", a friction clutch is attached to the motor shaft so that this clutch engages when air supply starts, and the purpose of this clutch is to act on the motor output side with the slave 11 of the clutch! fl'I
Tightening of the knot is done by using a friction clutch to detect warpage due to resistance, and using this anti-1li11 force to close a stop valve installed in the air supply passage. The setting is applied via a friction clutch, and should be determined by the reaction rotation angle of the fc operation piece.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

The one shown in Fig. 1 is a well-known Kesen torque wrench equipped with a torque generation mechanism;
3) and the output shaft (j) are directly connected to the air motor (4), and the forward/reverse switching valve mechanism provided in the main body (1) is connected to the air supply opening/closing valve provided in the grip handle (2). ) is connected to an internally provided air supply passage.

The rear shaft of the air motor (4); 45 is appropriately extended in size and a cone-shaped friction clutch is provided here, and the main drive motor having a truncated conical surface of the friction clutch ilO] The follower (121) is fixed to the base of the rear shaft (14'), and the follower (121) has a front part with a tapered inner surface that matches the conical surface of the above-mentioned 7σv1 child Il, and has a bottomed hole (one hole) formed in the center. 4) Upper ((
A coiled spring for pulling back + 1.i is inserted between the shaft end and the bottom end (1.i.
The outer periphery of ``4'' is stepped at the back of the front part with the tapered inner surface, and a cam clutch O0 is installed on the outer periphery in the middle part of which the needle cam transmits torque only in the reverse direction by a wedge action. An intervening operating piece is fitted integrally with the outer ring of the cam clutch, and a part of the ball i is inserted into a receiving hole FI31 centered at the end surface at the rear end of the follower (1'4). A piston with a hat-shaped cross section is arranged so that the center of the inner surface of the pole J4 comes into contact with the pole J4 and is fitted loosely.

A piston belonging to a follower 111J of a friction clutch 1dol is fitted into a part of a cylinder formed inside a motor cover (5) that covers this clutch mechanism, and is inserted into a part of this cylinder J7). A torsion spring with fixed ends is interposed between the open end l4 of the operating piece +2 and the facing surface of the operating piece -, and a protrusion gH is provided at a suitable position on the outer periphery of the operating piece +2 [) toward the motor side. It's a special job. Further, a part of an air supply passage (not shown) is branched behind the piston ill of the cylinder part 1η so that rice air is fed during air supply.

The outer curved part of the motor cover (+1), which incorporates the friction clutch IQI mechanism described above, coincides with the motor axis, and has a circularly protruding boss (on the outside) that forms part of the cylinder (1η).
5'), and the outer circumference of this boss (5) has a torque adjustment/
- Loosely fit the coil spring 17) into the outer periphery of the boss (5) with the ring (7), and connect the other end of the fitted coil spring 17) to the stepped part of the adjustment handle (B). Hole end surface i
The inner end surface of the adjustment handle □□□ is in contact with the seat surface (g) formed around the base of the boss (5') of the motor cover (5).
), a ball clutch (c) is fitted in a suitable position on the seat surface (g), and the inner end surface of the opposing adjustment handle (23) is divided into equal parts to control the required rotation. There is one place (24) at the corner that engages with the ball register in the pole clutch □□□ to position and stop, and the adjustment handle +
An instruction line is engraved on the outer periphery of 23+ in accordance with the distribution of the one positioning point (material), and the tightening torque can be easily set using the pointer (C) provided at the appropriate position on the cover (5). ing. Furthermore, this adjustment handle (5) is attached to the motor cover (5).
), the slit 16 is provided in an arc shape with the required length relaxed.
) protrudes inward from the protrusion (C) parallel to the axis, and the protrusion (2) of the operating piece (□□□) is in constant contact with the side surface of the tip of this protrusion.

The base of the gripping handle (2) that extends below the body of the main body (1) with a built-in air motor (4) (this position is not necessarily limited to this position; A forward/reverse switching valve +30+ for supply air is provided parallel to the motor axis (can be provided on the side), and this switching valve (G) is connected to the air supply passage or the main body (1) in the required distribution. Sleeve mll with a through hole @fi e+71 drilled to communicate with the exhaust passage
is bored in a fixed position, and inside the hole is formed a hollow 04 from the rear to the middle part with a diameter that engages the end of the sleeve button through the seal ring (T), and At the center of the tip, there is a switching valve with 3) of the operating shaft protruding outside the main body, which is inserted into the operating shaft (02).
A knob for switching between forward and reverse directions is attached to the protruding end. A hollow portion 06 is provided on the circumferential surface of the intermediate portion of this switching valve.
One ventilation hole (G) (36
is drilled on the outer periphery leading to the base of the operating axis, and an exhaust connection is provided at a position on the axis displaced by an angle of 90P from the axis passing through the six perforations of the ventilation hole μs, and at opposite positions across the center line. Grooves that serve as passages are formed in each of them, and communicate with an exhaust passage (7) formed in the main body ill at the time of switching.

The stop valve @1 installed inside a certain switching valve (to) is
A stop valve (old valve of 4 (2)) is fitted into the hollow part of the switching valve (c), and the valve stem ((
31 is formed with a slightly smaller diameter part (44) at the tip protruding from the hollow part 14'4 of the switching valve valve element (411), and a rotation stopper pin 441 is implanted in the middle part. Engage the pin i44 with the notch (b) at the end of the switching valve (c), and then insert the snap ring (
! The ring (441) and valve stem (43f)
ty, with a return spring (4) interposed between the base and the valve (41). Outlet side through hole 144
are aligned with the respective holes provided in the sleeve C31) and the switching valve 02 to open the air supply passage to the air motor (4), and in order to maintain this state, the motor cover (5) Between the boss (5) protruding from a part of the motor cover (5) and the support piece fitted on the side, there is a stopper decoy whose intermediate part is pivoted by a pivot pin Uη. The lower end of the valve cap engages with the narrow diameter part ←4 of the valve cap to lock the valve sleeve against the valve stem from sliding in one direction by air supply pressure. In addition, this stopper! 4
gj is the valve stem assembly diameter portion 14 at the lower end as shown in FIG.
4, and the free end side of the torsion spring 4 is engaged between the left side of the support pin and the eel, and the lower end of the lower end of the stopper The stepped portion is engaged with the step portion to prevent the valve from moving backward.

In the figure, the symbol (8) is the air supply pipe connection port, II is the opening/closing lever of the air supply valve, - is the silencer housed in the exhaust port, (9)
The tightening is the socket.

When using the torque wrench of the present invention, the compressed air supply hose is connected to the air supply pipe connection port (8), and the torque wrench of the present invention is handled in the same way as a conventional torque wrench, and the air supply valve opening/closing lever 1 is used.
When liIl is pulled, the air supply valve opens and pressurized air is supplied.
At this point, the switching valve (to) is set to the normal rotation side, so that the pressurized air is passed from the air supply passage in the grip handle (2) to the ventilation hole (to) provided with the valve f3BK of the switching valve cape. In accordance with this, air is supplied to the air motor (4) through the inlet side through hole and outlet side through hole I4 of the built-in stop valve, and the air motor (4) is activated. Rotate and move. At the same time, a part of the cylinder (1η
Pressurized air is also supplied to the inside, and the piston (14) is pressed and moves forward, and the follower (12) of the friction clutch lOj, which is disposed so as to be fitted onto the rear shaft (4') of the rotating motor, is connected to the built-in return mechanism. The main body moving forward and rotating against the spring (141 force!1)
When the clutch (10) is engaged, the front force is not transmitted to any other part, but only the front element (12) is engaged with the main element (1). The piston (1 barrel) rotates and is associated with this follower (12).The rotational force is cut off at the center via the pole (1), so that the piston does not perform any rotational action, and the operating piece that is fitted.
Since the cam clutch (151 is installed in the free movement direction, the protrusion Ql protruding outward from the cam clutch) is attached to the motor cover (5
) is in a state where it is held in contact with the protrusion (to) protruding inside.

When the tightening torque of the object is tightened by the rotational drive of the air motor (4) via the tightening torque generating mechanism, when the torque reaches the set limit, the tightening is instantaneously performed by the air motor (4) due to the reaction force. 4) rotates in the opposite direction, and accordingly, the friction clutch (10) and the front element 11 on the rear shaft (4') of the motor (4) also rotate in the opposite direction, and the driven element (+21) is fitted on the outer periphery. Since the operating piece (10) is attached via the cam clutch (10), it rotates with the slave (1) in the reverse direction, as shown in Fig. 4 when this clutch (10) is engaged. As the protrusion 1) moves forward and is located at the upper part of the stopper decoy located at the upper and lower positions in the figure, the operation piece (a) protrusion (21) that rotates with the follower (1) becomes the pivot point of the stopper decoy. When it comes into contact with the upper end, the stopper 4 is rotated and its lower end sloped surface (4) breaks the engagement with the stop valve @ duck valve stem (44) and stops. Benbenko t41
) is released, the valve @
0 retreats in the axial direction against the force of the return spring (49) applied to the valve stem i43, and as a result, as shown in FIG. hole (44,
+4% is closed, the air supply to the air motor (4) is cut off, and the air motor (4) is automatically stopped at +hL, the tightening operation is completed.

When the air supply to the motor (4) is stopped due to this stopping operation, the pressure that had been distributed to a part of the cylinder (I7) through the branched passage communicates with the air supply passage to the motor and pressurizes the motor (4). disappears, and the piston (16) is returned together by the force of the coiled spring (1) installed inside the follower (121), and the piston (16)
1) and the follower (1) are disengaged, and the friction clutch (
101 becomes open. Immediately before that, the operating piece (A) rotates back to the position where it contacts the protruding piece - and the protrusion (?11) by the force of the torsion spring, and the opening/closing lever Cυ of the air supply valve (E) is retracted. When the air supply valve pipe 5 is closed by removing the force, the air supply supplied to the switching valve Yato is stopped, and the valve of the stop valve 4 (
41) When the supply air pressure acting on the end face decreases, the four forces of the return spring push the valve back at the valve opening position, and the stopper (c), which had been jumped up at the large diameter part of the valve stem (c), is The force of the spring (49) causes the lower end of the valve stem to engage and come into contact with the narrow diameter part i of the valve stem, and the stopper's lower end inclined surface (
44 to prevent sliding and return the inside of the switching valve to its open state.

Since the torque wrench of the present invention has such a structure and function, when setting the torque for tightening, use the torque adjustment handle (4) + 2 (indicator line with multiple steps on the circumference).
7) Guidelines attached to the cover! 281 (C13)), as the number of the indicated line hexes J & increases in the counterclockwise direction in FIG. Tightening the operating piece 2 (to) through all brings the torque detection start position close to the connection activation point for the stopper (c). In short, when tightening, the smaller the amount of rotational displacement when the motor is reversed due to reaction force, the faster the air supply will be cut off. Tightening can be set so that the torque limit value is small by increasing the torque limit value and rotating the adjustment handle until the final indication line position 0) matches the pointer. Simply select the appropriate location and set the torque IJ. When tightening the torque adjustment handle, set it at the desired position by rotating it to set the torque, and the ball clutch (c) will be in the specified position by engagement with the pole of the ball clutch (c) and one place on the handle row side. I can gain weight.

As mentioned above, the torque wrench of the present invention cleverly utilizes the air pressure supplied to the motor to detect the limit of tightening torque using a friction clutch and a ring-shaped cam clutch. It is installed so that it can be connected and disconnected, and the tightening is done by the reaction of the torque generating mechanism.
The operation piece attached to the side operates the valve installed in the air passage, which is linked to cut off the air supply to the motor. Since it is a wrench, the tightening torque can be finely set by adjusting the handle externally, allowing reasonably accurate bolt and nut tightening work to be performed efficiently.

Further, according to the spirit of the present invention, the friction clutch is not limited to the -L arrangement and the embodiments, and a multi-disk type clutch or the like may be adopted as the friction clutch.

[Brief explanation of drawings]

The drawings show an embodiment of the torque wrench. Fig. 1 is a longitudinal sectional front view of the main parts, Fig. 2 is a right side view of Fig. %1, and Fig. 3 shows the stop valve and stopper. FIG. 4 is a diagram showing the state b during rotational operation, and FIG. 5 is a diagram showing a state in which the tightening torque limit is detected and air supply is cut off. (1)...Body (2)...Grip
Handle (3)...Tighten with torque generating mechanism (4)...Air motor (required...Motor rear shaft (I)...Output shaft (5)...Motor cover (5)... ...Boss (6) ...Slit (10) ...Friction clutch 1lli...
・Shu Senko (, 1 o...Junior Kiriko (14)
)...Returning coil spring...Cam clutch (1
υ...Piston (lη...Cylinder part 11
~...Torsion spring wire...Operation piece Ql...
・Protrusion (Recite...Tighten using the torque adjustment handle (
24)...Kubo place 12-yen...Ball clutch (goods)...Protrusion piece Punishment...Indicator line (c)...Indicator field...Switching
Valve (3)...Switching valve valve element 00δ...Vent hole body...Stop valve f41...Valve element 0 audience...Hollow part (c)...Valve stem (4
4...Small diameter capital (4 uniform...Reverse winding i4η...Pivotal hinge (c)...Stopper 144...Tilt. 6゛'') -30゜

Claims (1)

[Claims] In a torque wrench operated by an air motor, a friction clutch is disposed on the rear shaft of the air motor, and a driven element of the friction clutch with respect to a main element fixed to the motor side is associated with a piston of an operating cylinder provided within the motor cover. The structure is such that the driven element engages with the main mover only during air supply, and an operating piece with a protrusion is reversibly fitted on the outer periphery of the follower via a reversing gear 1 hicham clutch, and the air motor is connected from the air supply port to the air motor. A reciprocating stop valve is disposed in the air passageway, a notch is provided at the end of the valve stem, and a stopper that engages with this notch to keep the valve open is pivotally located in the vicinity. On the outside of the motor cover, there is attached an adjustment handle for setting the tightening torque that engages with the protrusion of the operation piece to enable setting of the reversal operation position in multiple stages. The operating piece on the friction clutch, the stopper, and the stop valve valve are associated with each other so that when the stopper is kicked, the stopper is released from holding the valve open, and the stop valve closes due to the air supply pressure, stopping the supply of air. The tightening of the torque wrench is characterized by an automatic control device.