JPS60104662A - Signal circuit for electric tool - 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] Industrial application 'f Invention-1, electric power tool for work, such as electric screwdriver Pso/Uster force type 11'+1 with mechanical clutch
When the dragon's clutch is tightened to a constant torque, the clutch moves one movement and the electric current d
There is a -C related to a circuit that extracts the fl and number of j.

1. Conventional configuration and its problems As shown in Fig. 1, the conventional power tool engages with the bit 1 and 2 and moves in the direction of the arrow, and the starter 3 switches the starting limit switch 4. 'I1.' to the push motor 5. When the power is supplied, the motor 6 starts rotating, and the motor 5
The rotational driving force is transmitted to the drive cam 6 and the driven cam 7, and the screw 2 is turned to tighten the screw. In Fig. 2, when the screw 2 reaches a certain torque, the bit 1 and the driven cam 7 stop, so the driven cam 7 tilts the drive cam 6, causing a displacement and compressing the i-lux spring 8 in the direction of arrow B. The cam ridge 6a and the top and bottom of the cam 6a are raised up, but at this time, the detection limit switch 9 is turned on by the movement of the driven cam 7 in the B direction. The motor 5 was stopped by a signal from a detection limit switch 9, and a screw tightening completion signal was output.

However, in the above configuration, in addition to the star limit switch, there must be four limit switches for detecting the completion of clutch operation, and by installing a switch on the tip rotation part in qJl, the diameter of the tool can be reduced. , the wiring is complicated, and the mechanical impact of the rimiso i-switch reduces its lifespan.
The problem was that it was disadvantageous in terms of space and reliability.

Purpose of the Invention In view of the above-mentioned drawbacks, the present invention has a structure in which a switch for supplying power to the motor is turned off by the movement of the switch rod when the clutch is activated, and stops the motor once. The present invention provides a signal circuit that can take out a tightening completion signal.

Composition of the Invention The present invention is a block/start type comprising a motor, a tip tool driven by the motor, a clutch located between the two, a switch located on the input wire side of the motor, and a switch rod leading from the clutch to the switch. In a power tool, the motor is rotated at the a45 point of the switch, and the moment the clutch moves and the slip point b closes, the relay is activated, and the contact signal is taken out to count the number of screw tightenings, defective wires, etc.
[It has a signal circuit that can check for moss, etc., and a unique limit switch that turns the motor on and off and outputs a screw tightening completion signal that can be applied in the bending direction.] have an effect.

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

FIG. 3 shows an overall diagram of the electric screwdriver using the signal circuit of the L power tool in this embodiment.1
0 is the motor, 11 is a gear part, 12 is a clutch part, 13
is a tip tool (hereinafter referred to as a focus). Clutch part 1
A switch rod 14 passes through the gear part 11, the center of the motor 10, and connects to a limit switch 16. All of these are covered with covers 1ea, 16b, and 16cmc. 17 is a signal code.

, 4 and 5 show the clutch portion 12 of FIG. 3 in detail, in which the driving force of the motor 1o is transmitted to the camshaft 18 through the gear portion 11. A ring cam 19 is attached to the camshaft 18 so as to rotate together with the camshaft 18, and a steel ball 21 is interposed between a hammer ring 20-1 that can slide on the camshaft 18 and a cam ridge 19a of the ring cam 19. The thrust bearing 22 and the spring seat 23 are operated to provide an elastic force to the L-lux spring 240. A lock cam 25 is installed in the center hole of the camshaft 18, and a lock cam 26 and a press-fit bushing 2 are connected to the center hole of the camshaft 18.
It is inserted in a state where it is biased in one direction by the spring 2 between 6 and 6. The lock cam 26 fits into the center hole of the bit holder 29, which is fitted into the cam shaft 18 with a spring 28 biased therebetween. A ball 3o is partially exposed to the center portion 25a of the lock cam 250 in the radial hole of the bit holder 29, and is fitted between the ball 3o and the inner diameter of the clutch pawl receiver 31 that slides on the bit holder 29. Although the clutch pawl receiver 31 slides on the bit boulder 29, the direction of rotation is restricted by a pawl 32. 33 is camshaft 1
8 is a ring fitted, 34 is a retaining ring fitted to the bit holder 29 via a spring 35, 36 is a pinot]・1
Number 3 is a steel ball for stopping. Note that one end of the torque spring 24 is connected to a different clutch case (not shown) for the entire clutch part 12.
is in contact with. Also, -ψ1h of the switch rod 14
1 is in contact with the end face of the lock cam, and the other end passes through the gear part 11 and the center of the motor 10 to reach the limit switch 16.

FIG. 6 is an electric circuit diagram showing the signal circuit of the present invention, and 15 is a mint switch that is turned on by moving the bit 13 in the axial direction;
The RYl beam operates at the a contact of the mint switch 16, and the a contact forms a self-holding circuit. The other a contact of RYl is the b contact of limit switch 15 and timer T.
1 and relay RY2. The b contact of a relay RY2 is connected between the a contact of the limit switch 15 and the bridge diode 0, and the b contact Tb of the timer T is connected to the relay RY1. F is a fuse, and SW is a switch for changing the rotation direction of the motor.

The operation of the signal circuit configured as described above will be described below.

As the bit 13 moves in the direction of arrow C, the bit holder 29 moves, and the four balls 3o in the bit holder 29 hit the slope of Bi' 26a of the lock cam 25 and move it, moving the switch rod in the direction of arrow E. to move the limit switch 15 by 1. The contact of the limit switch 15 falls to a 11111 and the relay RY1 operates.The relay RY1 is designed to hold itself at its a contact RY1a.At this time, the input power is connected to the bridge. It is supplied to the motor 10 through the diode D1 switch SW, and the motor 10 rotates.The driving force of the motor 10 is transmitted to the camshaft 18 through the gear part 11, and the ring cam 19 transmits it to the hammer ring 2Q via the steel ball 21. The interlocking pawl 20a at one end and the clutch pawl receiver pawl 31
It is transmitted to the bit holder 29 and the bit 13 through a. When the screw (not shown) reaches a certain torque, the bit 13 stops, but attempts to stop the hammer ring 20 through the reverse path. As the motor 10 attempts to rotate further, the steel ball 21 climbs the cam crest 19a of the ring cam 19 and moves the hammer ring 2o in the direction of arrow F against the torque spring 24. (Fig. 5) At this moment, the clutch pawl receiver 31 also moves in the direction of the arrow G, and the ball 30 in the bit holder 29 is moved by the lock cam 25 in the radial direction of the arrow H.
be moved in the direction At this time, the switch rod is moved by the movement of the lock cam 25 in the direction of the arrow, the limit switch 16 is turned off, and its contact point falls in the direction b. As a result, as shown in FIG. 6, the timer T and the relay RY2 start operating at the same time, and at one point bJi of the relay RY2, the power supply to the motor 1° is cut off and the rotation reaches IJ2. If the a contact of this relay RY2 is provided as a separate circuit, a signal can be obtained that the screw is tightened, the clutch is activated, and the motor has stopped. After a certain period of time, the timer T operates and its b contact Tb is cut off, and the relay RY1 is cut off, restoring the circuit to the nut state.

As mentioned above, start and stop the motor using the a and b contacts of the mint switch, and relay RY.

By incorporating RY, 2 and timer T and configuring a circuit as shown in Fig. 6, it is possible to output the screw tightening completion signal.
It becomes jJ' Noh.

In the embodiment, the electrolytic erosion voltage is expressed as an alternating current, but a direct current power source may be used, and in this case, the diode D may be removed.

Effects of the Invention As described above, the present invention provides a push-start electric tool that uses a timer to connect the a and b contacts of one limit switch operated by the action of a built-in clutch to By incorporating a relay, one relay's a
A screw tightening completion signal can be taken out at the l1 point, and this contact can be used to count the number of screws tightened, check for unfastened screws that occur when tightening screws, and construct structures without screws. The non-pull 114 configuration using a glue mint switch allows the screw tightening tool to be small and lightweight, and can be used not only for manual use, but also for automatic screw tightening machines and robots. It can be applied to various fields such as systems, and its practical effects are significant.

[Brief explanation of drawings]

Fig. 1 is a simplified diagram showing the conventional screw tightening completion detection structure of a power tool when the screw is rotating, Fig. 2 is a simplified diagram showing the screw tightening completion of Fig. 1, and Fig. 3 is an embodiment of the present invention. An overall sectional view of an electric screwdriver using the Shinto circuit of the electric upper tool as an example,
Figure 4 is a detailed +1'411 cross-sectional view showing the state of the clutch valve of the same embodiment before the screw tightening starts, Figure 5 is a detailed cross-sectional view showing the state of the clutch head of the same embodiment when the overlapping picture I of Figure 4 is completed, and Figure 6 FIG. 1 is an electrical circuit diagram showing a signal circuit of the present invention. 10...Motor, 12...Clutch section,
13... Bit, 14... Switch rod, 15... Limit switch, RYl, RY
2--IJ Fray T...Timer. Name of agent: Patent attorney Toshio Nakao and 1 other person
1 Figure 2

Claims (4)

[Claims] (1) A motor, a tip tool rotated and driven by the motor, a clutch located between the two, a switch that protects the motor, and a switch rod that operates the switch 4 when the tip tool moves in the axial direction. and a signal circuit that takes out the operation signal of the switch, and when the signal circuit rotates the motor with the a contact of the switch, When a torque is applied, the switch "LJJ9 change switch 412i
：WIL 1) il, :A second relay that operates at the B contact of the i switch, and a timer that is energized by the A contact of the first relay, and of the second relay]
#! : Power tool signal circuit that outputs l+me completion signal. (2) A counter is connected to the J point of the second relay, and the number of screws to be thinned can be determined in accordance with claim 8r! 1J, l'i
Signal circuit of the power tool described. (3) The signal circuit for a power tool according to claim 1, wherein a pilot lamp is connected to the contact point of the second relay of the appliance, so that completion of screw tightening can be visually confirmed. (4) Connect the sound-producing device to the second relay contact of the alarm,
A signal circuit for a power tool according to claim 1, wherein the signal circuit is configured so that completion of screw tightening can be confirmed by sound.