JPS5856771A - Motor type bolt clamping machine - 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 has two electric motors, a high-speed, low-torque electric motor and a low-speed, high-torque electric motor, and these two electric motors are rotated at the same time. Tighten bolts and nuts using either motor according to load fluctuations 51! Dynamic port tightening! ! I! It is related to.

In general, when tightening bolts using a bolt tightening machine, the tightening torque for the bolts and bolts is higher than the set tightening torque. When IC is reached and the power of the bolt tightening machine is cut off, the rotational speed of the output shaft of the bolt tightening machine is ``J'', the inertia rate of the rotating part of the bolt tightening machine is ``J'', and the spring constant of the bolt being tightened is ``k''. Final tightening torque T that acts on the bolt
Then, there is a relationship of T=i陀T, and the larger the duck, the final tightening torque T of inertia
It has a great influence on W. The smaller the value, the smaller the influence of inertia on the final tightening torque T.

It takes longer to tighten bolts and nuts. Therefore, in order to tighten bolts and nuts with the set tightening torque in a short time, the bolts and nuts must be tightened until they come into contact with the tightening member.
When the nuts are freely rotating, the bolts and nuts should be rotated at high speed and low torque, and when the bolts and nuts are in contact with the tightening member, they should be rotated at low speed and high torque. .

Therefore, two electric motors are used, one for high-speed, low-torque and one for low-speed, high-torque. When the nut contacts the tightening member and the current of the high-speed, low-torque motor becomes equal to the set value, the high-speed, low-torque motor is stopped, the low-speed, high-torque motor is rotated, and the bolt/nut is tightened to the low-speed, high-torque state. When the current becomes equal to the current value corresponding to the set predetermined tightening torque value, the low-speed, high-torque motor is stopped and the bolts and nuts are tightened in step 51! A dynamic bolt tightening rock has been proposed. However, with this type of electric bolt tightening machine, by the time the bolt or nut being tightened comes into contact with the tightening member, the bolt or nut may be threaded 8K, or there may be deformed parts or rust on the threaded part. If there is a location etc., the load on the high speed low torque motor will be N7IO, and when its current reaches the set value, the high speed low torque acid motor will stop and the low speed low torque motor will be tI11! Since the machine is switched to the I machine, free rotation of bolts and nuts is performed by the low-speed, high-torque electric motor from then on. It took a long time to tighten the bolts and nuts, and the long bolts had the disadvantage of significantly lowering the rate of chestnut production.

In view of the above points, Hontomei has developed a high-speed, low-torque electric motor that transmits high-speed, low-torque to a socket drive unit via a high-speed, low-torque transmission unit, and a socket drive unit that transmits high-speed, low-torque torque to a socket drive unit via a low-speed, high-torque transmission unit and a one-sided clutch. Electric bolt tightening with a low-speed, high-torque electric wJa that transmits sluggish high torque to the drive unit [1! [
A high-speed, low-torque electric motor and a low-speed, high-torque electric motor
The high-speed, low-torque electric motor and the low-speed, high-torque electric motor are automatically switched and used according to load fluctuations when the bolts and nuts are freely rotating. When the bolt/nut contacts the tightening member and the current of the high-speed, low-torque motor exceeds the set value, it automatically switches to the low-speed, high-torque motor, tightens the bolt/nut, and then tightens the bolt/nut. An electric bolt that automatically cuts off the current of the high-speed, low-torque motor and the low-speed, high-torque motor and stops them when the torque reaches the set tightening torque, reducing the time required for tightening and improving work efficiency. It provides a tightening machine.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram of the mechanical structure of an electric port tightening machine according to an embodiment of the present invention, and FIGS. 2 and 3 are block diagrams of embodiments of a control device.

In Figure 1, electric bolt tightening l! 1 is a high-speed, low-torque electric motor 2 (hereinafter abbreviated as 'electric motor 2'), a high-speed, low-torque transmission section 3, a low-speed, high-torque electric motor 4 (hereinafter, abbreviated as electric motor 4), and a low-speed-high torque transmission section 5. , one-way clutch 6, socket) Illfls7. It consists of a control device 8 and a plug 9 connected to an external device (not shown).

The high-speed low-torque transmission section 3 consists of a reduction mechanism 10 mounted on the output shaft of the TS machine 2, and a gear 11 attached to the output shaft of this reduction mechanism 1O. Transmits high speed and low torque.

The low-speed high-torque transmission s5 is a ms mechanism connected to the output shaft of the electric IIJ 4, and the output shaft is connected to the one-way clutch 6 through the one-way clutch 6.

A low bending high torque is transmitted to the socket shaft 13 of the socket sounding part 7.

= The direction clutch 6 is installed between the low-speed high-torque transmission section 5 and the socket drive N7, and the rotation of the output shaft of the low-speed high-torque transmission section 5 is caused by the rotation of the socket shaft 13 of the socket body IIh section 7.
The output of the low-speed high-torque transmission section 5, that is, the low-speed high torque, is directly transmitted to the socket shaft 13 of the socket sounding section 7 only when the rotation becomes higher than the rotation speed of the socket.

The socket drive unit 7 has a socket @13 connected to the one-way clutch 6 at one end and a socket 2 removably attached to the other end, and this socket shaft 13Kb! It consists of a gear 14 that meshes with the gear 11 of the high-speed low-torque transmission section 3, and the bolt/nut fitted in the socket 12 is connected to the high-speed low-torque transmission section 3 or the low-speed high-speed torque transmission section 3 depending on the tightening condition *. The output of the torque transmitting section 5 is transmitted.

As shown in FIG. 2, the control device 8 includes a high-speed and low-torque electric motor control section 15 (hereinafter abbreviated as the control section 15) and a low-speed and high-torque electric motor control section 15 (hereinafter abbreviated as the control section 16). ) and a gate switching circuit 17 as a current cutoff circuit.
It is composed of. Also.

Armature # Iso 2 and l1EIII Iso 4 are armature 2A, respectively.
, 4A and series-wound field windings 2F, 4F, which are connected in a row to the scissors 19 and 20, respectively, and a common switch may be installed on the main body of the device 10 or other easily operated location. The ltI+ control unit 15 includes a thyristor 19, a current detector 22 that detects the current of the motor 2, and this current detector 2.
an amplifier 23. which rams and outputs the current detected by the amplifier 23.2; Current limit setter 24 for setting the current limit value of the electric motor 4!122. Input the current difference between the current limit value set in this current limit setter 24 and the output of the amplifier 23, and
As the current approaches the set current limit value, the phase of the thyristor 19 is narrowed down to gradually reduce the rotation of the motor 2, and when the current difference becomes almost zero, the motor 2
It is composed of a phase control circuit 25 that maintains the rotation in a state of almost zero rotation. The control unit 16 includes a thyristor 20, a current detector 26 that detects the current of the motor 4, and this current detector 2.
The current difference between the current value set in the torque setting device 28 and the output of the amplifier 27 is outputted to the gate interrupt circuit 17. The gate switching circuit 17 inputs the current difference, and operates when the current difference becomes zero, outputs a gate switching signal to the thyristors 19 and 20, and simultaneously cuts off the gates of the motor 2. and -a of telephone number machine 4
m is shut off and stopped. Figure 493 shows the circuit in Figure 2 with the soft start circuit 18 added, and this soft start circuit 1B corresponds to the predetermined tightening torque value of the bolts and nuts to be tightened, which is set in the torque setting @28. This is provided to prevent the gate cutoff circuit 17 from operating due to the starting current of the electric heater 4 when the current value is smaller than the starting current value of the electric motor 4.

Next, the operation of the electric bolt tightening machine 1 having five or more configurations will be explained with reference to Fig. 1 and Fig. 2. 2, set the predetermined tightening torque for the bolt/nut to be tightened on the torque setting device 28, fit the socket 12 to the bolt/nut to be tightened, and turn on the switch 21. 19, and simultaneously the piezoelectric motor 4 is also started via the thyristor 2G. Until the bolt/nut comes into contact with the tightening member, the power of the electric motor 2 is transmitted via the high-speed, low-torque transmission section 3.

The signal is transmitted to the socket shaft 13 of the socket drive unit 7, and allows the bolt/nut to rotate freely at high speed and low torque via the socket 12. In this case, the rotation of the output shaft of the low-speed high-torque transmission section S is lf! 111: Since it is much lower than the rotation at t, it is cut off by the one-way clutch 6 and is not transmitted to the socket shaft 13. Normally, the rotation speed of the socket shaft 130 is about 200 rpm when driven by the high speed low torque transmission section 3, and about 1 Orpm when driven from the low speed high torque transmission section 5.

Next, when the bolt comes into contact with the tightening member and enters the tightened state, the current in the motor 2 increases, and the current detector 2
When the current value detected by the motor 2 approaches the current limit value set in the current limit setting device 24, the rotation of the motor 2 is gradually decreased under the control of the control section 15, and the detected current value of the motor 2 approaches the current limit value set in the current limit setting device 24. When it becomes approximately equal to the set current limit value,
The electric motor 2 reaches almost zero rotation and maintains that state. On the other hand, this reduced rotation of 1 m2 of electric power is transmitted to the socket shaft 13 of the socket drive section 7 from the high-speed low-torque transmission section 3. When the rotation of this socket shaft 13 becomes lower than the rotation of the output shaft of the low-speed high-torque transmission section 5, the power of the electric motor 4 is transferred from the low-speed high-torque transmission section 5 to the socket 1 moving section 7 via the one-way clutch 6. The torque is transmitted to the socket shaft 13, and bolts and nuts are tightened at low speed and high torque via the socket 12. In this case, the current difference between the current value of the electric motor 8I4 detected by the current detector 26 and the current value corresponding to the predetermined tightening torque of the bolt/nut set in the torque setting device 28 is determined by the control unit □16 at the gate. It is output to the cutoff circuit 17. The gate cutoff circuit 17 operates when the input current difference becomes zero, and cuts off the gates of the thyristors 19 and 20 at the same time to cut off the currents of the electric motor 2 and the electric motor 4 and stop them. Therefore, the bolt is.

The bolt is tightened to the predetermined tightening torque set on the torque setting device 28. Next, when the switch 21 is turned off, all electric circuits are reset and the socket 12 of the electric bolt tightening machine is tightened.
and fit it into the next bolt/nut.

By repeating the same operations as described above, bolts and nuts can be tightened continuously. Also.

In the bolt/nut tightening work mentioned above, the electric l12
Therefore, when the bolts and nuts are freely rotated at high speed and low torque via the high-speed and low-torque transmission section 3 and the socket drive section 7, galling may occur in the threaded part of the bolts and nuts, or f'2 There are deformed parts and rusted parts on the same part.
Wil
The electric motor 2 is maintained at zero rotation by the control unit 15,
The bolts are connected to a low speed high torque transmission section 5 by an electric motor 4. Via the one-way clutch 6 and the socket drive unit 7,
Can be rotated freely at low speed and high torque. And bolt
There is no galling on the threaded part of the
When the nut escapes the deformed surface or rusted part of the threaded part and the load becomes lighter as in m, the bolt/nut is moved by the drying motor 2 via the high-speed low torque transmission part 3 and the socket drive part 7. It can be rotated at high speed and low torque. Therefore,
Bolts and nuts are subject to the load 'XItl when they rotate freely.
Depending on I, the bolt/nut is automatically switched to high-speed, low-torque or low-speed, high-torque and is allowed to rotate freely, so the bolt/nut has a short time from when it starts to rotate freely until it comes into contact with the tightening member and enters the tightened state. The time required for free rotation can be greatly reduced.

The conventional embodiment of the control device shown in FIG.
When starting the motor 4, the motor 4 is operated in the same manner as shown in FIG. 2, except that the motor 4 is softened by the soft start circuit 18 so that the gate cutoff circuit is not activated by the starting current.

In addition, instead of the soft start circuit, the electric power detected by the current detector 26 for a certain period of time from the start of the electric motor 4! l! It is obvious that a dead band circuit may be provided between the current detector 26 and the amplifier 270 in order to prevent the current value of 4 from matching the set value of the torque setting device 28.

As described above, the electric bolt tightening machine of the present invention is as follows.

Through the high-speed low-torque transmission part, the socket drive WLK high-speed low-torque electric motor transmits high-speed low torque, and through the low-speed high-torque transmission part and one-way clutch.

Socket)l! ! The low-speed, high-torque electric motor that transmits low-speed, high-torque to the moving parts is rotated at the same time, and the high-speed, low-torque electric motor and the low-speed, high-torque electric motor are automatically switched in response to load fluctuations during free rotation of bolts and nuts. The time required for free rotation of bolts and nuts when used by hand can be greatly reduced, and the production grit rate can therefore be improved.

[Brief explanation of the drawing]

@ Figure 1 is a schematic diagram of the mechanical structure of one embodiment of the present invention, Figure 2 is a schematic diagram of the mechanical structure of an embodiment of the present invention.
FIG. 3 is a block diagram of an embodiment of the control device. 1--Electric bolt tightening machine, 21--Electric motor for high speed and low torque, 3--High speed and low torque transmission section, 4
...Low speed high torque electric motor, 5...Low speed high torque transmission section, 6...One way clutch, 7...Socket m moving part, 8...Control device, 9...Connector, 10...Il
& reach mechanism, 11, 14...gear, 12-...socket, 13...socket shaft, 15...high-speed, low-torque electric rod control section, 16...low-speed, high-torque electric motor control N
%17... Gate switching circuit, 18... Soft start circuit, 19, 20... Thyristor, 21...
・Switch, 22, 26--Current detector, 23
, 27...Amplifier, 24...1! flow limit setter,
25... Phase control circuit, 28... Torque setting device. Patent applicant Shibaura Seisakusho Co., Ltd. Figure 3

Claims (1)

[Scope of claims] The socket ffi moving part driven by the low speed high torque transmission part via the high speed low torque transmission part or the one-way clutch, the high speed low torque electric motor and the low speed high torque electric motor are simultaneously rotated, and the bolt During the free rotation of the bolt/nut until the nut contacts the tightening member and starts tightening the tightening member, the high-speed, low-torque transmission section and the low-speed, high-speed The torque transmission part is automatically switched and the bolt/nut is rotated through the socket sliding part, and when the bolt/nut □ comes into contact with the tightening member and enters the tightening state 70!VC, the high speed and low The torque motor is held at almost zero rotation, and the one-way clutch and the low-speed high-torque transmission section tighten the bolts and nuts via the socket drive section using the low-flow, high-torque motor, and the bolts marked PIa are tightened. - An electric bolt tightening machine comprising a one-way control device that simultaneously interrupts the currents of the high-speed, low-torque electric motor and the low-speed, high-torque electric motor when the nut's tightening torque reaches a predetermined tightening torque. (2 ) A control device detects the current of the high-speed, low-torque motor, and when the detected current value becomes equal to a set current control value, brings the high-speed, low-torque motor to a state of almost zero rotation. Detects the current of the high-strength, low-torque motor control unit to be held and the low-speed, high-torque motor, and corresponds to the detected current value and the predetermined tightening torque value set for the hole bolt to be tightened. A low-speed high-torque electric motor control unit that outputs the current difference between the electric current TI/lIl and the output of the low-speed high-torque electric current control 1s is inputted, and when the current difference becomes zero, The electric bolt tightening machine according to claim 1, comprising a current cutoff circuit that simultaneously cuts off 4ItiL of the high-speed, low-torque electric motor and the low-speed, high-torque electric motor. The current of the floating rock for low torque is drawn sideways, and this detected '1t
When the tit value becomes equal to the set current control setting value, the high-speed low-torque motor control section that maintains the high-speed low-torque motor at almost zero rotation and the low-speed high-torque motor's Detects the current value and outputs the current difference between the detected current value and the current value corresponding to the set predetermined tightening torque + 1IllvC of the bolt/nut to be tightened. input the current difference between the outputs of the low-speed, high-torque electric motor #, and when the current difference becomes zero, the high-speed, low-torque electric motor and the low-speed, high-torque electric motor! The motor according to claim 1, comprising a current interrupting circuit that simultaneously cuts off the current of the motive power, and a circuit that prevents the current interrupting circuit from operating due to the starting current of the low speed and high torque t@iso. Electric bolt tightening machine/