JPS6326339Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ratchet feed malfunction detection circuit, and more particularly to a ratchet feed malfunction detection circuit for an automatic machine such as an automatic inspection device for electronic parts.

Conventionally, in automatic inspection equipment and the like, ratchet feeding has been used as one of the inexpensive intermittent conveyance methods. However, if the feed pitch width and speed are incorrectly designed, the fulcrum bearing of the ratchet pawl will wear out, the tip of the ratchet pawl will wear out, and in the worst case, the ratchet pawl and rack will disengage, resulting in malfunction of the feed. This may occur. When an intermittent conveyance system is adopted as a mechanical device, it is often required that the number of feed pitches be accurate with respect to the elapsed conveyance time of the conveyance jig. For this reason,
In particular, the occurrence of the above-mentioned defects can be avoided by measuring and inspecting the characteristics of multiple electronic components placed on the conveyance jig in relation to the number of pitch feeds, and classifying them into grades based on the test results. This is a fatal flaw for machines such as automatic inspection equipment, which store graded electronic components in separate storage boxes while continuously feeding them in pitches. Particularly during intermittent conveyance of a small pitch width, it is difficult to visually detect when the feed of one pitch is out of order.

It is an object of the present invention to provide a ratchet feed malfunction detection circuit which improves the above-mentioned drawbacks of the prior art.

According to the present invention, the output of the first photoelectric switch is
A first timing signal is connected to one terminal on the input side of the 1AND circuit, and a first timing signal is connected to the other terminal on the input side of the first AND circuit, and the output terminal of the first AND circuit is connected to the output terminal of the shift register circuit exclusively. The output of the second photoelectric switch is connected to one of the input terminals of the OR circuit, the output of the second photoelectric switch is connected to one terminal of the input side of the second AND circuit, and the first timing signal is connected to the other terminal of the input side of the second AND circuit. , the output of the second AND circuit is connected to one of the remaining input terminals of the exclusive OR circuit, the output terminal of the exclusive OR circuit is connected to one of the input terminals of the third AND circuit, and The other input terminal of the third AND circuit is connected to the second timing signal, the output terminal of the third AND circuit is connected to the input terminal of the flip-flop circuit, and the shift input terminal of the shift register circuit is connected to the third timing signal.
There is obtained a ratchet feed malfunction detection circuit characterized in that a timing signal is connected and a reset signal is connected to the reset terminal of the shift register circuit and the reset terminal of the flip-flop circuit.

In particular, according to the present invention, a reflector plate installed on a conveyance jig is connected to a reflector plate installed along the conveyance path.
A circuit for detecting a ratchet feed malfunction can be obtained by detecting a ratch-feeding malfunction using a reflection type photoelectric switch and comparing and determining the outputs after a predetermined time has elapsed using a shift register circuit equipped with a timing circuit.

Hereinafter, the present invention will be explained with reference to the drawings.

FIG. 1 is a perspective view of an embodiment of the device using the detection circuit of the present invention, and FIG. 2 is a circuit diagram of the present invention configured with an IC. Further, FIG. 3 is a timing diagram showing the relationship among the detection 11a, determination 12a, shift 13a, etc.

In FIG. 1, a reflecting plate 1a that reflects light is provided at the front of the transport jig 1 in the transport direction, and a reflecting plate 1b is provided at the rear thereof. Furthermore, a rack 2 is provided at the lower part of the conveyance jig 1, and the reciprocating movement of the ratchet claw 3 causes the conveyance jig 1 to be intermittently conveyed in the direction of the forward arrow.
In addition, a first photoelectric switch 4 is installed at a side position on the ratchet feed path where the leading end of the conveying tool 1 conveyed by the ratchet claw 3 first reaches, A second photoelectric switch 5 is installed at a position somewhat longer than the entire length of the conveying jig 1 with respect to the first photoelectric switch 4. The power shaft of the drive motor 6 is connected to the shaft of a drive cam 7, and the rotational displacement of the drive cam 7 is transmitted via a drive lever 8 to a power transmission piece 10 attached to a drive shaft 9. generates a reciprocating motion.

Further, timing signals 11a, 12a, 13a shown in FIG. 3 are generated by timing cams 11, 12, 13 directly connected to the shaft of the drive cam 7.

Next, the detection circuit of the present invention will be explained with reference to FIG. The reset signal shown in Figure 2 operates automatically the moment power is supplied to this circuit, sets the initial conditions of the IC that has a memory function in the circuit to zero, and also cancels the output when a malfunction is detected. This is done by human manipulation. In addition, the shift register circuit 14 sends a timing signal 1 as many times as the value obtained by dividing the installation interval distance of the first photoelectric switch 4 and the second photoelectric switch 5 by the pitch width of the intermittent feed.
3a is input, the input signal is output.

Next, with reference to FIGS. 1 to 3, the function of the circuit according to the present invention in conjunction with the forward movement of the conveying jig 1 will be explained.

First, as shown in FIG. 1, the power of the drive motor 6 is transmitted via the drive cam 7, the drive lever 8, the drive shaft 9, and the ratchet pawl 3 to the rack 2 provided at the bottom of the transport jig 1. 1
is conveyed, and when the first reflecting plate 1a is detected by the first photoelectric switch 4, the detection signal is "true".
occurs. This detection signal is the timing signal 11
a and the timing signal 13a (FIG. 3),
The signal is stored in the shift register circuit 14 (FIG. 2), and thereafter, this signal is shifted toward the output in the shift register 14 every time the conveying jig 1 is moved intermittently. When the transfer jig 1 continues to be transferred and the reflection plate 1a is detected by the second photoelectric switch 5, the detection signal "true" and the timing signal 1
The output “true” of the second AND circuit 16 based on the logical product of 1a is the input terminal 1 of the exclusive OR circuit 18.
If there is no malfunction in the feed of the transport jig 1 by this time, the shift register circuit 14
The detection signal "true" input at the position of the first photoelectric switch 4 is output from the exclusive OR circuit 1.
It is input to the remaining input terminals of 8. In the exclusive OR circuit 18, the output is "false" only when the input signals of the first photoelectric switch 4 and the second photoelectric switch 5 match, so as long as there is no malfunction in the feeding of the conveying jig and tool, the output is "false". Keep the output "false".

If there is a malfunction in the feeding of the transport jig 1, the output of the exclusive OR circuit 18 becomes "true", and the output of the third AND circuit 17 becomes "true" by logical product with the timing signal 12a. '' is input to the flip-flop circuit 19, and its output continues to be output as an alarm signal, resulting in an alarm circuit (not shown) or a circuit (not shown) that stops the entire mechanical device.
Activate. This state (warning signal held) continues until a reset signal is input by human operation.

Thereafter, the rear reflector 1b goes through the same process to determine whether there is a malfunction in the pitch feed, so if the reflectors 1a and 1b pass the second photoelectric switch 5 safely, the first and second Photoelectric switch 4,
This means that there is no pitch shift within the section 5.

Further, to explain the timing relationship with reference to FIG. 3, detection timing 11a, determination timing 1
2a, shift timing 13a is a timing that occurs each time the ratchet claw 3 makes one reciprocating motion, and therefore occurs between the time when the conveyance jig 1 stops after moving one pitch and just before the next movement starts. It is.

Referring to the role of each timing, the detection timing 11a is a timing signal that rises immediately after the conveying jig 1 finishes moving one pitch and stops, and the detection timing 11a is a timing signal that rises immediately after the conveying jig 1 finishes moving one pitch and stops.
The detection signals of the reflection plates 1a and 1b of the conveyance jig 1 to be detected by the photoelectric switch 5 are transmitted to the conveyance jig 1.
It is used as a gate signal to take out only when it is stopped.

In addition, the judgment timing 12a is used to output the "true" output of the exclusive OR 18 as an alarm output before the next drive of the transport jig 1 starts if there is a malfunction in the pitch feed of the transport jig 1. This is a signal used as a gate signal for the third AND circuit 17. Therefore, when a malfunction is detected, the output of the flip-flop circuit 19 becomes "true" at the same time as the determination timing signal 12a rises, and continues until the reset signal is input.

Next, the shift timing signal 13a has the role of sequentially transferring the internal information of the shift register 14 one bit at a time in synchronization with the pitch feed of the conveyance jig 1, and the transfer of one pitch of the conveyance jig 1 is started. Output immediately before

As described above, according to the present invention, when a pitch feed malfunction occurs, it can be reliably detected by optical and electrical means, and it is possible to detect that a pitch feed error has occurred in the conveying jig. The value is enormous.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the circuit of the present invention. Figure 2 is a circuit diagram of this invention composed of ICs. FIG. 3 is a diagram showing timing relationships such as feed cycle, stop time, detection, judgment, and shift. 1... Transport tool, 1a, 1b... Reflector plate (attached to the transport tool), 2... Rack, 3...
Ratchet, 4, 5...Photoelectric switch, 6...
... Drive motor, 7... Drive cam, 8... Drive lever, 9... Drive shaft, 10... Power transmission piece, 11, 12, 13... Timing cam, 11
a, 12a, 13a...timing signal, 14...
...Shift register, 15...1st AND circuit, 1
6...2nd AND circuit, 17...3rd AND circuit, 1
8...Exclusive OR circuit, 19...Flip-flop circuit.

Claims (1)

[Scope of utility model registration request] In a ratchet feed malfunction detection circuit that has first and second photoelectric switches along a ratchet feed conveyance path that conveys a conveyor unit equipped with a rack by reciprocating movement of a ratchet claw, the output of the first photoelectric switch is connected to the output of the first AND circuit. A first timing signal is connected to one terminal on the input side, and a first timing signal generated during a period in which the conveyance section is stopped is connected to the other terminal on the input side of the first AND circuit.
The output terminal of the 1AND circuit is connected to the input terminal of the shift register circuit, the output terminal of the shift register circuit is connected to one of the input terminals of the exclusive OR circuit, and the output of the second photoelectric switch is connected to the input terminal of the second AND circuit. and the first timing signal is connected to one terminal of the input side of the second AND circuit, and the output of the second AND circuit is connected to one of the remaining input terminals of the exclusive OR circuit. The output terminal of the exclusive OR circuit is connected to one of the input terminals of the third AND circuit, and the output terminal of the exclusive OR circuit is connected to one of the input terminals of the third AND circuit, and the output terminal of the exclusive OR circuit is connected to one of the input terminals of the third AND circuit. The output terminal of the third AND circuit is connected to the input terminal of the flip-flop circuit, the shift timing signal is connected to the shift input terminal of the shift register circuit, and the reset terminal of the shift register circuit and the flip-flop circuit are connected. A ratchet feed malfunction detection circuit characterized in that a reset signal is connected to a reset terminal of the circuit.