JPH0525824Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention is an electromagnetic tackifier that drives nails in a magazine from a nail drive opening into a workpiece such as a construction board using the attraction of a plunger caused by the excitation of an electromagnetic solenoid. The present invention relates to a protection device for controlling the number of times a hammer is operated during nail driving, that is, the number of times an electromagnetic solenoid is repeatedly operated, especially when a nail is being driven abnormally when a nail cannot be driven even after repeated hammering.

(Prior art) Conventionally, in the case of an electromagnetic tacker that drives nails into board materials etc. by suction drive of a plunger by exciting an electromagnetic solenoid with direct current from an AC power supply, the driving rate of one nail is 1. The electromagnetic solenoid is repeatedly energized only once or a specified number of times at predetermined time intervals.In this method, for example, the head of the nail may change due to changes in the hardness of the board material depending on the position where the nail is driven. In addition, each time the length or thickness of the nail changes, the number of times the nail is driven, that is, the number of times the power is supplied to excite the electromagnetic solenoid, must be adjusted. However, there were still drawbacks such as nail heads remaining due to changes in the hardness of the board and nails being driven in too far.

(Problem to be solved by the invention) As a countermeasure to this problem, a method is used in which an electromagnetic solenoid is repeatedly excited until the plunger reaches the stroke end. If the electromagnetic solenoid cannot be driven into the nail by repeatedly energizing the electromagnetic solenoid when it hits a previously driven nail, the electromagnetic solenoid may become abnormally hot due to the increased number of repeated energizations, which may cause the electromagnetic tacker to malfunction or malfunction. There were some drawbacks.

Therefore, the purpose of this invention is to accurately detect the point at which nail driving is completed without being affected by heat or shock, and to detect changes in the hardness of the board, etc., or the length or thickness of the nail without making any troublesome adjustments. Even if the nail driving speed changes, the nail driving is kept constant at the optimal state, and the electromagnetic solenoid is repeatedly energized when the nail is hit by a knot in the tree or by a previously driven nail. To prevent abnormal heat generation of an electromagnetic solenoid and failure or malfunction of an electromagnetic tacker due to the abnormal heat generation when a nail cannot be driven in even though the nail is driven in.

(Means for solving the problem) That is, in the present invention, the main switch is turned on and the electromagnetic solenoid is energized, and the plunger is suctioned against the biasing force of the spring to eject the nails in the magazine. The electromagnetic solenoid is repeatedly energized at arbitrary time intervals in a state where the stroke of the plunger at the time of suction has not reached the preset stroke of the plunger, and the plunger reaches the set stroke. In an electromagnetic tactile sensor that detects the occurrence of an incident using an on signal from an optical sensor by sensing light, a time-limiting circuit outputs a time-up signal after a preset period of time after the main switch is turned on, or after the main switch is turned on. a counter that outputs a number-up signal after a preset number of operations, and includes an on signal from the optical sensor for detecting a full stroke when the plunger reaches a set stroke, and a time-up signal from the time limit circuit or a time-up signal from the counter. The electromagnetic tack is configured to stop energizing the electromagnetic solenoid when either one of the number-up signal and the number-up signal is generated.

(Example) Next, the configuration of an example of the present invention will be described with reference to the drawings.

Due to the attraction of the plunger 3 against the biasing force of the spring 2 due to the excitation of the electromagnetic solenoid 1, the hammer 4 protruding from the tip of the plunger 3 drives the nail 6 stored in the magazine 5 from the nail drive opening 7. The handle 9 of the electromagnetic tatsuka 8 that shoots out one by one has a main switch operated by an automatic return lever 10.
SW1 is installed and the main body 11 of the electromagnetic tack 8
Optical fibers 12 and 13 are connected to the plunger 3 in the middle part.
The optical fibers 12 on one side are connected to the LED of the projector of the optical sensor 16 attached to the circuit board 14 in the handle 9 via the holder 15, and the other optical fiber 1
3 is connected to the phototransistor 17 of the light receiver of the optical sensor 16, and on the top of the plunger 3 there is a light output changing section for changing the output from the optical sensor 16 when the plunger 3 reaches a set stroke, in this case. , a through hole 18 is formed.

Next, FIG. 2 is an electrical control circuit diagram of this embodiment, in which the electromagnetic solenoid 1 of the electromagnetic tether 8 is connected to an AC power supply AC via a silicon AC control element TRC1, and a photocoupler is connected to the silicon AC control element TRC1. Light receiving element 19 of PC1 and resistors R1 to R4
a trigger circuit 20 consisting of a protection resistor R5,
A series circuit of the capacitor C1 is connected to form a drive circuit 21 for the electromagnetic solenoid 1.

A full-wave rectifier RE1 connected to the AC power supply AC via a transformer PT1 is connected to an inverter IT1 which inputs a trapezoidal wave formed by a resistor R6 and a Zener diode ZD1 and outputs a pulse at the zero cross of the AC waveform, and a diode D1. The main switch is connected to the stabilized power supply circuit element Q1, which is connected to the full-wave rectifier RE1 via the
A one-shot circuit 23 is connected via a xerox circuit 22, which consists of SW1, resistors R7 to R9, and a transistor TR1, and synchronizes the output from the main switch SW1 at the zero-crossing of the AC waveform.
In addition to being connected to a one-shot circuit 23 consisting of resistors R10 to R12, capacitors C3 and C4, inverters IT2 and IT3, a NOR circuit NOR1, and an AND circuit AND1, a timer circuit 24, in this case,
Resistors R13, R14, capacitor C5, NAND circuit
A monostable multivibrator timer circuit 24 consisting of NAND 1 and inverters IT4 and IT5 is connected, and the output from the optical sensor 16 and the timer circuit are connected to an LED and a phototransistor 17 connected to the power supply Vcc via resistors R15 and R16, respectively. 24
The output from the NAND circuit NAND2 is input to the K terminal, and the output from the main switch SW1 via the inverter IT6 is input to the J terminal via the integrating circuit 25 consisting of a resistor R17 and a capacitor C6. An AND circuit whose inputs are the output from the JK flip-flop circuit JK・FF1 and the output from the one-shot circuit 23.
The output from AND2 is input to transistor TR2 via resistor R18 to control trigger circuit 20 of silicon AC control element TRC1.

Next, the operation of this embodiment will be explained.

When the main switch SW1 is turned on while the nailing port 7 of the electromagnetic tacker 8 is in contact with a workpiece such as a plate material in response to the driving of the nail 6, the time constant of the one-shot circuit 23 synchronizes with the zero cross of the AC waveform. At regular intervals, the silicon AC control element TRC1 is triggered and turned on via the photo coupler PC1 and the trigger circuit 20, and this turn-on operation is performed by the optical sensor 16, which prevents the plunger 3 from suctioning during the entire stroke.
This is repeated in the OFF state of
A time-up signal is output from the timer circuit 24 after a certain period of time when the nail driving is originally completed, and the output of the JK flip-flop circuit JK FF1 is inverted to complete the nail driving operation. 3 has suctioned the entire stroke, the optical sensor 16 turns on and the output of the JK flip-flop circuit JK/FF1 is reversed to complete the nailing operation. In this completed state, the nailing opening 7 of the electromagnetic tacker 8 is moved to the next nail. When the main switch SW1 is turned on while the main switch SW1 is in contact with a workpiece such as a plate material in response to striking, the above operation is repeated again.

Next, FIG. 4 shows another embodiment of the present invention, in which
In this case, a decimal counter 26 such as Toshiba's TC4017BP is used in place of the timer circuit 24 shown in Fig. 2, and a preset number of operations is performed after the main switch SW1 is turned on.In this case, the workpiece is not particularly hard. The configuration is as follows, except for outputting the up signal a certain number of times after the driving of the nail 6 is originally completed and stopping the energization to the electromagnetic solenoid 1.
Both the action and the effect are the same as in the above embodiment.

(Effects of the invention) In this invention, the main switch is turned on and the electromagnetic solenoid is energized, and the plunger is sucked against the urging force of the spring to drive the nails in the magazine out of the nail drive opening and into the workpiece. , in a state where the stroke of the plunger during suction has not reached a preset stroke of the plunger, the electromagnetic solenoid is repeatedly excited at arbitrary time intervals, and light is sensed to indicate that the plunger has reached the set stroke. In an electromagnetic tactile sensor that is detected by an on signal of an optical sensor, a timer circuit outputs a time-up signal after a preset period of time after the main switch is turned on, or a preset constant operation after the main switch is turned on. a counter that outputs a number-up signal after the number of times has elapsed, and either an on signal from the optical sensor for detecting a full stroke when the plunger has reached a set stroke, a time-up signal from the time limit circuit, or a number-up signal from the counter; There is an electromagnetic tamper that stops energizing the electromagnetic solenoid when one of these occurs.

As a result, the present invention can accurately detect the point at which nail driving is completed without being affected by heat or shock, and can detect changes in the hardness of the board or the length of the nail without making any troublesome adjustments. The electromagnetic solenoid keeps the nail driving constant and optimal even when the thickness changes, and the electromagnetic solenoid keeps the nail driving constant even if the nail thickness changes. This has the effect of effectively preventing abnormal heat generation of the electromagnetic solenoid and the resulting failure or malfunction of the electromagnetic tassel when a nail cannot be driven in even after energizing the electromagnetic solenoid.

In addition, especially in the case of the electromagnetic tassel of the present invention, since it uses an optical sensor to detect the set stroke, it is less likely to break due to impact, but if it does break, the electric circuit will most likely remain off. In addition, a malfunction specific to the optical sensor is that the light emitting/receiving part becomes dirty and the optical sensor remains off.

In other words, an optical sensor with a damaged or malfunctioning optical sensor and its electrical circuit remains off because the optical sensor detects the set stroke even though nail driving has finished and the set stroke has been reached. In that case, the electromagnetic tacker will not detect the set stroke and stop, but will stop after a certain amount of time or a certain number of operations, so the electromagnetic tacker will be able to continue working even if the optical sensor fails. However, as a practical matter, only the necessary number of electromagnetic tackers are brought to the work site, so if the electromagnetic tackler breaks down and becomes unusable, it immediately interferes with the work. This has the effect of effectively eliminating the drawbacks of

[Brief explanation of the drawing]

Figure 1 is a cutaway front view of one embodiment of the present invention;
FIG. 3 is an electrical circuit diagram thereof, FIG. 3 is an operational diagram thereof, and FIG. 4 is an electrical circuit diagram of another embodiment of the present invention. 1...Electromagnetic solenoid, 2...Spring, 3
... Plunger, 4... Hammer, 6... Nail, 8...
Electromagnetic tatsuka, 12, 13... Optical fiber, 16...
...Light sensor, 18...Through hole, 24...Timer circuit, 26...Decimal counter, SW1...Main switch.

Claims (1)

[Scope of utility model registration request] When the main switch is turned on, the nails in the magazine are ejected from the nail outlet and driven into the workpiece by suction of the plunger against the biasing force of the spring caused by the excitation of the electromagnetic solenoid, and the stroke of the plunger during the suction is The electromagnetic solenoid is repeatedly energized at arbitrary time intervals in a state where the preset stroke of the plunger has not been reached, and an on signal from an optical sensor is generated by sensing light to indicate that the plunger has reached the set stroke. In the electromagnetic tackler to be detected, a time limit circuit that outputs a time-up signal after a preset fixed time period after the main switch is turned on, or a counter that outputs a number-up signal after a preset fixed number of operations after the main switch is turned on. and when either an on signal from the optical sensor for detecting a full stroke when the plunger has reached a set stroke, a time-up signal from the time limit circuit, or a number-up signal from the counter is generated, the electromagnetic An electromagnetic tactile device that is characterized by stopping energization to a solenoid.