JPH0627315Y2 - Workpiece attachment confirmation device - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention detects the pressure of an air passage opening on the mounting surface of the workpiece to confirm the mounting of the workpiece. Regarding the device.

[Prior Art] Conventionally, as a work piece attachment confirmation device for confirming the attachment of the work piece by detecting the pressure of an air passage opening on the attachment surface of the work piece, for example, the actual open sho-58- As disclosed in Japanese Laid-Open Patent Publication No. 117323, a technique for confirming the attachment state (that is, the close contact state) of a workpiece by detecting zero air pressure is already known.

[Problems to be Solved by the Invention] However, in such a conventional technique, the air pressure is detected when a predetermined time sufficient to reach the final pressure elapses, for example, when the air pressure is zero. If it is determined that the air pressure (final pressure) is higher than a predetermined threshold value, it is determined that the work piece can be attached. If it is determined that the air pressure is lower than the threshold value, the work piece is determined. It is set so that it is determined that the mounting of is not possible. In this way
The time required for the conventional confirmation operation is set to about 2 because the air pressure is set to a time sufficient to reach the final pressure.
It takes as long as ˜3 seconds, which makes the working time unnecessarily long, and improvement is desired from the viewpoint of working efficiency.

This invention was made in view of the above-mentioned problems, and the purpose of this invention is to set a short time for confirming the mounting,
It is an object of the present invention to provide a device attachment confirmation device capable of improving work efficiency.

[Means for Solving the Problem] In order to solve the above-mentioned problems and to achieve the object, a work piece attachment confirmation device according to the present invention is provided with an air passage opening to a work piece attachment surface and the air passage. A supply means for supplying air to the workpiece through the passage, a pressure sensor for continuously detecting the pressure in the air passage, and a final pressure according to the pressure rise change characteristic detected by the pressure sensor. At the previous point in time, the predicting means for predicting this final pressure, and if the final pressure predicted by this predicting means is greater than or equal to a predetermined value, it is judged that the mounting state is acceptable, and if it is lower than the predetermined value. , And a determination means for determining whether or not the mounting state is impossible.

[Operation] In the work attachment confirmation device configured as described above, the pressure in the air passage is continuously detected by the pressure sensor, and the final change is made by the predicting means based on the detected change characteristic of the pressure rise. We anticipate the final pressure before the pressure is reached. In this way, the time at which the determination means determines whether or not the mounting state is possible is earlier, and the time required for confirmation of the mounting is set shorter as a whole than when the final pressure is actually detected. Become.

[Embodiment] The construction of an embodiment of a work attachment confirmation apparatus according to the present invention will be described in detail below with reference to the accompanying drawings.

As shown in FIG. 1, an attachment confirmation device (hereinafter, simply referred to as an attachment confirmation device) 10 for a workpiece according to this embodiment includes:
Mounting surface 14 on a mounting base 14 to which the workpiece 12 is mounted
The air passage 16 opened to a is provided. An end portion of the air passage 16 has an air pump 18 as a compressed air supply source.
It is connected to the. The air pump 18 is configured to be capable of discharging compressed air at a constant weak air pressure (that is, an air pressure set so as not to affect the mounting state of the workpiece 12).

On the other hand, in the middle of the air passage 16, the pressure detection passage 2
0 is connected, and the pressure sensor 2 capable of continuously detecting the pressure is provided at the end of the pressure detection passage 20.
2 is attached. That is, the pressure sensor 22 is configured to output a signal corresponding to the pressure in the pressure detection passage 20 as an analog signal.

The pressure sensor 22 is connected to a control mechanism 24 for confirming the mounting state of the workpiece 12 on the mounting surface 14a based on the detection signal obtained from the pressure sensor 22.

That is, when the workpiece 12 can be mounted on the mounting surface 14a in a good condition, that is, when the degree of adhesion between the workpiece 12 and the mounting surface 14a is sufficient, the air passage 16 is covered by this member. Since the workpiece 12 is completely closed, the pressure detected by the pressure sensor 22 has an extremely high value. On the other hand, if foreign matter such as dust is present between the work piece 12 and the mounting surface 14a, or the contact surface of the work piece 12 to the mounting surface 14a has a chip or the like, the mounting state is judged to be impossible. In this case, there is a gap between the work piece 12 and the mounting surface 14a. For this reason, the air passage 16 has the workpiece 1
2, the pressure sensor 2 is not completely closed.
The degree of increase in the detected pressure of 2 will be suppressed to a low level.

In other words, the control mechanism 24 detects and manages the final pressure when the pressure rises, so that the workpiece 12
It will be possible to confirm the state of attachment to the attachment surface 14a.

Therefore, the control mechanism 24 is provided with a signal amplifier 26 for receiving the detection signal from the pressure sensor 22, amplifying and outputting the detection signal, and the signal amplifier 26 stores the rising pattern of the pressure change. It is connected to the unit 28 and an acceleration detection unit 30 that detects the zero value of the acceleration of the change in the pressure increase. The pattern storage unit 28 and the acceleration detection unit 30 are connected to a prediction unit 32 that predicts a change pattern of pressure increase.

In addition, the predicting portion 32 includes the mounting surface 14 of the workpiece 12.
A rise pattern registration unit 34 in which various pressure rise patterns that change according to the attachment state to a are registered in advance is connected, and in the prediction unit 32, the zero value of the acceleration of pressure rise in the acceleration detection unit 30 is connected. Based on the change pattern of the actual pressure increase until the pressure rise is detected, the best matching rise pattern is selected from the various rise patterns registered in advance in the rise pattern registration unit 34.

It should be noted that the various rising patterns registered in advance in the rising pattern registration unit 34 each include a final pressure value after a sufficient time has elapsed, and the selected rising pattern is included in each final pressure value. The final pressure value in the pattern is what is defined as the expected final pressure value P _P.

On the other hand, the predicting unit 32 is connected to a pattern determining unit 36 that determines whether the workpiece 12 is attached to the attachment surface 14a based on the estimated pressure increase pattern. Here, a reference pattern registration unit 38 in which a predetermined reference pattern that constitutes a threshold value as a determination criterion of possibility is registered is connected to the pattern determination unit 36. Here, in this reference pattern, the final pressure value P _{o of the} pressure that rises based on this reference pattern is such that
It is set so as to constitute the minimum pressure (setting limit) required to be determined to be securely attached to the.

Then, in the pattern determination unit 36 described above, the prediction unit 32
The expected final pressure value P _P based on the pressure increase pattern predicted in step S1 is compared with the reference final pressure value P ₀ based on the reference pattern registered in the reference pattern registration unit 38, and the expected final pressure value P _P is determined to be the reference final pressure value. If the pressure value is higher than P ₀ ,
Assuming that the mounting state of the work piece 12 on the mounting surface 14a is acceptable, an OK determination result is output, and when the expected final pressure value P _P is lower than the reference final pressure value P ₀ , the workpiece is processed. It is configured to output the determination result of NG assuming that the object 12 is not mounted on the mounting surface 14a.

The operation of confirming the mounting state of the workpiece 12 on the mounting surface 14a in the mounting confirmation device 10 configured as described above will be described below.
This will be described with reference to the diagram shown in the figure.

First, when the workpiece 12 is placed on the mounting surface 14a of the mounting base 14 by a transfer device (not shown), the air passage 16
Is closed by the work piece 12, and the air pump 18
Based on the compressed air supplied from the pressure sensor 22
The detection value of starts to rise. The detection value of the pressure sensor 22 is stored in the pattern storage unit 28 in relation to the change with time, and the course of the change in the pressure increase is stored as shown by the chain line A in FIG.

On the other hand, in parallel with the pattern storage operation in the pattern storage unit 28, the acceleration detecting unit 30 detects the acceleration of the change in the pressure increase based on the detection value from the pressure sensor 22. Then, when the acceleration detection unit 30 detects that the detected acceleration reaches zero (indicated by reference numeral t ₀₁ in the drawing), a detection signal is output to the prediction unit 32.

In the predicting unit 32, at the time when the detection signal from the acceleration detecting unit 30 is input, based on the pattern storage information from the pattern storage unit 28, a plurality of pressure increase patterns registered in advance in the increase pattern registration unit 34. From
The best matching pressure rise pattern (solid line B in Fig. 2
Indicate. ) Is selected. The selected pressure increase pattern B has the final pressure value that will be reached when the time elapses, that is, the predicted final pressure value P _P1 information. Then, the selected pressure increase pattern information is sent to the pattern discriminating unit 36, and in the pattern discriminating unit 36, the reference pattern (indicated by a broken line C in FIG. 2) previously registered in the reference pattern registering unit 38 is displayed. The reference final pressure value P ₀ and the expected final pressure value P _P1 are compared and considered.

Here, as described above, the expected pressure increase pattern in this case is based on the pressure increase change measured only until the time point t ₀₁ when the acceleration of the change in pressure increase reaches zero, as indicated by the alternate long and short dash line A. , As shown by the solid line C, the predicted final pressure value PP1 is the reference final pressure value P1.
Since the value is higher than ₀ , the pattern determination unit 36 determines that the mounting state of the workpiece 12 on the mounting surface 14a is acceptable, and outputs a determination result of OK.

On the other hand, as shown by the chain double-dashed line D, the predicted pressure rise pattern is predicted as shown by the solid line E based on the pressure rise change actually measured until the time t ₀₂ when the acceleration of the change in pressure rise reaches zero. If this is the case, this expected final pressure value P
_{Since P2} becomes a value lower than the reference final pressure value P ₀ , the pattern determination unit 36 determines that the mounting state of the workpiece 12 on the mounting surface 14a is impossible and outputs the NG determination result. .

As described above in detail, in this one embodiment, the acceleration of the pressure change at the place where it always occurs becomes zero before the pressure change reaches the final pressure without actually measuring the final pressure. Time point t ₀₁ . At t ₀₂ , at this time t ₀₁ . t ₀₂
The final pressure value is predicted based on the change pattern of the pressure increase actually measured up to the predicted final pressure value P _P1 . P _P2 ,
The reference final pressure value P ₀ as a threshold value is compared. Thus, according to this embodiment, in comparison with the entire confirmation required time T _S including the processing time T ₀ for the confirmation processing from the time point t ₁ at which the final pressure is conventionally measured, Overall confirmation required time T _{T1 in the example} .
T _T2 will be a short time.

Therefore, according to the attachment confirmation apparatus 10 of this embodiment, the time required to confirm the attachment of the workpiece 12 to the attachment surface 14a is shorter than that of the conventional case, and as a result, the working time is shortened as a whole. Therefore, work efficiency can be improved.

It is needless to say that the present invention is not limited to the configuration of the above-described embodiment and can be variously modified without departing from the gist of the present invention.

For example, in the above-described embodiment, in the control mechanism 24 that specifically executes the confirmation operation, the time t ₀₁ . The final pressure value is predicted based on the pattern of change in pressure increase measured up to t ₀₂ , and the predicted final pressure values P _P1 and P _P2 are compared with the reference final pressure value P ₀ as a threshold value. There is. However,
The present invention is not limited to the configuration using such a pattern, and may be configured as a modified example as described below.

That is, as is clear from the above description, the plurality of pressure patterns registered in advance in the rising pattern registration unit 34 change without overlapping each other. As a result, in this modification, for example, the pressure is the pattern A.
In the case where the change occurs at the time t, the measured pressure value P ₁₁ at the time t ₀₁ when the acceleration of the pressure change in the acceleration detection unit 30 becomes zero, and the reference pressure value P ₀₁ in the reference pressure increase pattern at the time t _01. When the measured pressure value P ₁₁ is higher than the reference pressure value P ₀₁ , the expected final pressure value P
_{Since P1} is also higher than the reference final pressure value P ₀ , the pattern is selected as in the above-described embodiment and the OK determination result is output without executing the operation of comparing with the reference pattern.

Further, in this modification, when the pressure changes in the pattern d, the measured pressure value P ₁₂ at time t ₀₂ is lower than the reference pressure value P ₀₂ in the reference pressure increase pattern at this time t ₀₂ is Since the predicted final pressure value P _P2 is always lower than the reference final pressure value P ₀ , the pattern is selected as in the above-described embodiment, and the operation of comparing with the reference pattern is not performed. Output the discrimination result.

As described above, in this modified example, since the operation of selecting a pattern does not have to be executed as in the embodiment, the processing time T ₀ is further shortened, and as a result, the confirmation required time T of the embodiment is obtained. Compared with _S , the confirmation required time of this modified example is further shortened.

Further, in the above-described embodiment, the compressed air is supplied from the air pump 18 to the air passage 16, but the air passage 1 is not limited to such a configuration.
The same effect can be achieved even if the negative pressure air is applied to 6 through a suction pump.

[Advantages of the Invention] As described in detail above, the attachment confirmation device for a workpiece according to the present invention includes an air passage opening on the attachment surface of the workpiece,
Supplying means for supplying air to the workpiece through the air passage, a pressure sensor for continuously detecting the pressure in the air passage, and a final pressure according to the pressure rise change characteristic detected by the pressure sensor. Before this, the predicting means for predicting this final pressure, and if the final pressure predicted by this predicting means is greater than or equal to a specified value, it is judged that the mounting condition is OK, and if it is lower than the specified value. Is equipped with a determination means for determining whether or not the mounting state is impossible.

Therefore, according to this invention, it is possible to provide a mounting confirmation device for a workpiece which can improve the working efficiency by setting a short time for confirmation of the mounting.

[Brief description of drawings]

FIG. 1 is a block diagram schematically showing the construction of an embodiment of a workpiece mounting confirmation device according to the present invention; and FIG. 2 is a diagram for explaining the confirmation operation. In the figure, 10 ... Workpiece mounting confirmation device, 12 ... Workpiece, 14 ... Mounting base, 14a ... Mounting surface, 16 ... Air passage,
18 ... Air pump, 20 ... Pressure detection passage, 22 ... Pressure sensor, 24 ... Control mechanism, 26 ... Signal amplifier, 28 ... Pattern storage section, 30 ... Acceleration detection section, 32 ... Prediction section, 34
... ascending pattern registration unit, 36 ... pattern determination unit, 38 ...
It is a reference pattern registration unit.

Claims (1)

[Scope of utility model registration request] 1. An air passage opening to a mounting surface of a workpiece, a supply means for supplying air to the workpiece through the air passage, and a pressure sensor for continuously detecting the pressure of the air passage. According to the pressure rise change characteristic detected by the pressure sensor, the predicting means for predicting the final pressure and the final pressure expected by the predicting means are equal to or more than a predetermined value before reaching the final pressure. In this case, the device for confirming the attachment of a work piece is provided with a determination means for determining whether the attachment state is possible and for determining whether the attachment state is impossible when the value is lower than a predetermined value.