JPH0755654A - Device for checking clicking feel of control key - Google Patents

Abstract

PURPOSE:To automate the checking of the clicking feel of a control key assembled to a product. CONSTITUTION:A device for checking the clicking feel of a control key has a key pusher portion for pushing a control key 2; sensor portions 5, 9 for detecting the displacement and load of the control key 2 being pushed; an A/D converter portion 11 that converts displacement and load detection signals from analog to digital form; a differentiating portion 13 for converting the information into a differential function having a differential of load with respect to each displacement; an interval dividing processing portion 14 for dividing the differential function into displacement intervals; a clicking-feel characteristic value calculating portion 15 for calculating the characteristic value of the clicking feel from the intervals; and a judging portion 16 for judging if the control key is normal by applying the characteristic value of the clicking feel in a predetermined criterion formula.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation key click feeling inspection device for inspecting an operation feeling called a click feeling in an operation key of an electric product.

[0002]

2. Description of the Related Art As an operation key for an electric product, an ergonomic approach has been developed to develop a key that has a click feeling and has a good tactile feel. Therefore, there is an increasing demand for automation of inspection of such operation keys having a click feeling.

An example of a conventional automatic inspection apparatus is shown in FIG.
0, a description will be given with reference to FIG.

In FIG. 10, 1 is a product to be inspected and 2 is an operation key on the product 1. Reference numeral 3 denotes a fingertip of the key pressing portion, which is attached to the tip of the key pressing rod 4. The pressure when the operation key 2 is pressed with the fingertip 3 is transmitted to the pressure sensor 5 (load cell) and detected. 6 is fingertip 3
Is an air cylinder, 7 is its valve, and 8 is air piping. Reference numeral 9 is a displacement amount sensor (differential transformer) for sensing the displacement of the fingertip 3. Reference numeral 10 denotes a click feeling inspection unit, which is a storage device in the click feeling inspection unit 10 by A / D converting and sampling the pressure signal input from the pressure sensor 5 and the displacement amount signal obtained from the displacement amount sensor 9. To store.

The click feeling inspection unit 10 simultaneously performs A / D conversion and sampling of the pressure signal and the displacement amount signal. Since the pressure signal and the displacement amount signal obtained at the same time correspond to each other, a displacement-load characteristic curve which is a function of the load with respect to the displacement can be obtained. In FIG. 11A showing a displacement-load characteristic curve of a key having a click feeling, P is a characteristic curve at the time of pressing,
R is a characteristic curve at the time of returning. As characteristic points characterizing this displacement-load characteristic curve, a starting point A indicating the start of the curve, maximum points B and G at which the load has a maximum value, minimum points C and F at which the load has a minimum value, and the end of the curve are shown. An end point H, a displacement amount increase end point D, and a displacement amount decrease start point E are extracted. However, since the load vibrates finely due to the influence of noise (electrical noise, etc.) and fine irregularities appear on the characteristic curve, the maximum and minimum cannot be uniquely obtained. Therefore, only when the difference between the maximum value and the minimum value is larger than a given parameter (set to a value larger than the noise and smaller than the decrease in the load when a click feeling occurs), the maximum and minimum values are recognized. FIG. 11B shows the displacement-load characteristic curve approximated to the line segment connecting the respective characteristic points. From these characteristic points and line segments, the difference between the loads of B and C, the difference between the loads of G and F, the value of the load of B, and the slope of the line segment connecting A and B are calculated, and these are within the desired range. If it is, the product is judged to be good, and if it is out of the range, it is judged to be defective.

Next, another conventional example will be described with reference to FIGS.
Will be described with reference to. 12, the difference from the conventional example of FIG. 10 is that there is no displacement amount sensor (differential transformer) 9. The click feeling inspection unit 10 includes the pressure sensor 5
Only the pressure signal input from the A / D converter is sampled and stored in the storage device in the click feeling inspection unit 10. At this time, if the sampling interval is fixed, the obtained pressure signal sequence becomes a time-series signal, which can be regarded as a function of load with respect to time (hereinafter referred to as a time-load characteristic curve).

FIG. 13A shows a time-load characteristic curve of a key having a click feeling. As a characteristic point characterizing this time-load characteristic curve, a start point A indicating the start of the curve,
The maximum points B and G where the load has a maximum value, the minimum points C and F where the load has a minimum value, the end point H indicating the end of the curve, the end point D of the displacement increase, and the start point E of the displacement decrease are extracted. To do. However,
The maximum and minimum values cannot be uniquely obtained due to the influence of noise (electrical noise, etc.), so the load difference between the maximum value and the minimum value is a parameter that is given in advance (greater than noise and the load decreases when a click feeling occurs). (Set to a smaller value) is regarded as maximum and minimum only if larger than. FIG.
(B) is obtained by approximating the time-load characteristic curve to a line segment connecting each characteristic point. From these characteristic points and line segments, the difference between the loads of B and C, the difference between the loads of G and F, the value of the load of B, A,
The inclination of the line segment connecting B is calculated, and if these are within the desired range, it is determined that they are good products, and if they are outside the range, it is determined that they are defective products.

[0008]

By the way, the inspection of the operation key may be inspected as a key alone or as a key incorporated in a product for consumers. Of these, as for the key as a single item, the key maker itself sets the design standard, so in many cases automatic inspection according to the design standard is performed using the above method, etc., but it was incorporated into the product. For the key, we rely entirely on human resources for the following reasons.

That is, when the key is incorporated in the product,
The key displacement-load characteristic function changes significantly depending on the rigidity of the product itself, the material of the key top (many plastic or rubber is used) between the key and the human finger, and the mounting state of the key. Resulting in. Specifically, "N"
The temporary drop in the letter-shaped load may become small or may disappear altogether. Not only may the design criteria for the single key not be used, but it may not be possible to detect each feature point.

Although the inspection is performed manually by the reason as described above, the operator requires skill and the inspection result varies due to individual difference of the operator, physical condition and mood.
Further, there is a problem that the worker may have tendonitis, and automation of inspection of the operation keys incorporated in the product is strongly demanded.

In view of the above-mentioned conventional problems, it is an object of the present invention to provide a click feeling inspection apparatus which can automate the inspection of an operation key having a click feeling even when incorporated in a product.

[0012]

SUMMARY OF THE INVENTION An operation key click feeling inspection apparatus according to the present invention comprises a key pressing portion for pressing the operation key, and a sensing portion for detecting the displacement and load when the operation key is pressed, or only the load. And a detection signal of displacement and load, or an A / D conversion unit for A / D converting the detection signal of load, and a differential function having the A / D converted information for displacement or a differential value of the load with respect to time. A differential processing unit for converting into a section, a section division processing unit for dividing a differential function into sections of displacement, a click feeling characteristic value calculation section for calculating a click feeling characteristic value from the divided section, and a click feeling characteristic value is predetermined. And a determination unit that determines whether or not the operation key is normal by applying the determination formula described above.

[0013]

According to the present invention, displacement-load characteristics, or time-
Obtain the differential function of the load characteristic, divide the differential function into sections according to the size of the differential value, and judge the quality of the click feeling based on the click feeling characteristic value at the boundary of the section. Even if the temporary reduction in the absolute value of the load, which is a feature of the single key because it is incorporated, disappears, it is possible to determine the quality.

Further, if both the displacement and the load are detected, a more reliable inspection can be performed, and if only the load is detected, the displacement detecting sensor is not used, so that the cost can be reduced.

[0015]

Embodiment 1 Hereinafter, a click feeling inspection device for an operation key according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 5.

In FIG. 1, 1 is a product to be inspected, 2 is an operation key on the product 1, 3 is a fingertip of a key pressing portion, 4 is a key pressing rod, 5 is a pressure sensor (load cell), and 6 is a fingertip 3.
, An air cylinder 7 for driving the valve, 8 an air pipe, 9 a displacement sensor (differential transformer) for sensing the displacement of the fingertip 3, and 10 a click feeling inspection unit, which have been described in the conventional example. Since the constituent elements are the same as those in FIG. 10, the description thereof is cited and the detailed description is omitted here.

Click feeling inspection section 10 in the present embodiment.
Is a pair of A / D converters 11 for A / D converting the output signals of the pressure sensor 5 and the displacement sensor 9, and an A / D converter.
A function creation unit 12 that calculates a displacement-load function from the converted information, a differential processing unit 13 that differentially processes the displacement-load function to convert it into a differential function, and a segment division process that divides the differential function into displacement intervals. It is provided with a unit 14, a characteristic value calculation unit 15 that calculates a click feeling characteristic value from the divided sections, and a judgment unit 16 that applies the click feeling characteristic value to a judgment formula and judges whether the operation key is normal.

A method of inspecting a click feeling with the above configuration will be described below. First, the basic idea will be described. From the data obtained from the displacement amount sensor 9 and the load sensor 5, a displacement-load characteristic curve as shown in FIG. 3 is obtained. This curve is divided into the following three parts.

Diaphragm characteristic part having positive inclination (characteristic caused by resistance of diaphragm) Transition part having negative or nearly zero inclination (characteristic generated when the diaphragm is inverted) Base characteristic part having large positive inclination (hard electrode) The characteristic generated by the resistance of the base) In the processing of this embodiment, the displacement-load characteristic curve is divided into the above three parts based on the differential function, and the values of the displacement and load at the points B and C at the boundary are clicked. It is obtained as a sense characteristic value.

The operation will be described below with reference to the flowchart of FIG.

First, in step # 1, a time-displacement function is created by sampling the output data of the displacement amount sensor 9. Next, in step # 2, the time-load function is created by sampling the output data of the load sensor 5.

Next, in step # 3, a displacement-load function as shown in FIG. 3 is created from the time-displacement function and the time-load function. This is obtained from the time-displacement function and the time-load function by connecting the displacement amount and the load obtained at the same time. The displacement amount is not output at a constant interval because there is a portion that is largely displaced and a portion that is not, but by interpolation, a displacement-load function having displacement and load as variables is obtained. Here, the sampling time interval between the displacement amount sensor 9 and the load sensor 5 does not have to be a constant time interval. However, it is necessary to shorten the sampling time interval so that the accuracy of interpolation does not decrease.

Next, at step # 4, the differential processing is performed by performing the filtering by the Gaussian filter shown in FIG. The characteristic of this Gaussian filter is that it has a smoothing effect in addition to the differentiation, and the effect of minute noise can be eliminated by this effect. When the filtering process by the Gaussian filter is expressed by an equation, O _j = Σ I _i * exp {−0.5 · (i−j) ² / σ
² } where O is an output, a differential operation value, I is an input, the value of the sampling point in the displacement-load function of FIG. 3, σ is a coefficient, and the value determines the degree of smoothing. It

FIG. 4 is a curve obtained by differentiating the characteristic curve of FIG. 3, and this curve will be referred to as a primary differential curve hereinafter. Figure 4
, X is a base characteristic detection threshold, y is a diaphragm characteristic detection threshold, and z is a transition portion detection threshold. These threshold values correspond to the diaphragm characteristic, transition portion, and base characteristic of each operation key of each product. It is set experimentally in advance so that the portion can be detected.

Next, in step # 5, the base characteristic portion is extracted. Since the base characteristic part has a large positive slope as described above, the value of the differential becomes very large. Therefore, a portion having a differential value larger than the threshold value x is set as a base characteristic portion. Then, a point that intersects the threshold value x is set to C ′ as a temporary start point of the base characteristic portion, and then scanning from the point C ′ toward the left side is performed. Get the starting point C.

Next, in step # 6, the transition portion and the diaphragm characteristic portion are extracted. The scanning is performed from the starting point C of the base characteristic portion to the left side, and the point at which the diaphragm characteristic detection threshold value is equal to or more than y is defined as the temporary end point B ′ of the diaphragm characteristic portion, and then B ′.
Scanning from the point to the right, the diaphragm characteristic portion end point B is obtained at the point where the transition detection threshold value z is equal to or less than the threshold value. By adopting such a method, it is possible to properly detect the boundary of each portion even when the inclination of the transition portion is small and there is noise. As described above, the section of the characteristic curve can be divided.

Next, in step # 7, the click feeling characteristic value is calculated. That is, the following click feeling characteristic values are calculated from the displacements and loads at points B and C.

(1) Maximum force (load at point B) (2) Minimum force (load at point C) (3) Click value (difference between minimum force and maximum force) (4) Stroke 1 (displacement at point B) (5) Stroke 2 (displacement at C point) (6) Stroke difference (distance between B point and C point-equal to length of transition section) (7) Click inclination (inclination between B point and C point-transition section) There is a characteristic value when pushing and when returning. The maximum value at the time of pushing and the minimum value at the time of returning are generally called “pushing force” / “returning force”.

Finally, in step # 8, the presence or absence of a click feeling is determined by a determination formula. Here, it is determined whether the operation key is normal by applying the click feeling characteristic value to a predetermined determination formula. As the judgment formula, as shown in the following formula,
There is a method of setting an upper limit and a lower limit for each click feeling characteristic value.

LL _n ≤C _n ≤UL _n where C _n is the nth click feeling characteristic value, UL _n is its upper limit value, and LL _n is its lower limit value.

(Embodiment 2) Next, an operation key click feeling inspection apparatus according to a second embodiment of the present invention will be described with reference to FIGS. The configuration of the inspection apparatus in this embodiment is basically the same as that of the first embodiment shown in FIG. 1, and only the differences will be described here by using the description thereof. In this embodiment, the displacement sensor 9 is not provided, only the output signal of the load sensor 5 is input to the click feeling inspection unit 10, and the single A / D conversion unit 11 is provided. It is configured to generate a time-load characteristic curve.

The inspection operation in this embodiment also has many parts in common with the first embodiment, and only the parts different from the first embodiment will be explained. Further, in the data processing flowchart shown in FIG. 7, a step # having the same last digit as the step corresponding to the step in the flowchart of FIG. 2 of the first embodiment is attached.

In this embodiment, the data output from the load sensor 5 is sampled at regular time intervals to obtain the time-load characteristic curve of FIG. Hereinafter, the displacement-load characteristic curve in the first embodiment is replaced with the time-load characteristic curve, and the same processing is performed to obtain the differential curve in FIG. 9 and the following click feeling characteristic values are calculated.

(1) Maximum force (load at point B) (2) Minimum force (load at point C) (3) Click value (difference between minimum force and maximum force) (4) Click slope (points B and C) Inclination between-inclination of transition part) For each of these, there is a characteristic value at the time of returning when pressed. The difference from the first embodiment is that there is no characteristic value regarding the stroke.

Then, these click feeling characteristic values are applied to a predetermined judgment formula to judge whether or not the operation key is normal.

In the above embodiment, the Gaussian filter is used for the primary differentiation, but other filters having the effect of the primary differentiation may be used.

Further, as a judgment formula, click feeling characteristic value C
It goes without saying that a linear function of ₁ , C ₂ , ... Or a multi-dimensional function f _m (C _1, C _2, ...) As shown in the following expression may be used.

LL _m ≤f _m (C _1, C _2, ...) ≤ UL _m

[0039]

According to the click feeling inspection device for an operation key of the present invention, the differential function of the displacement-load characteristic or the time-load characteristic is obtained as described above, and the differential function is sectioned according to the magnitude of the differential value. By classifying and judging whether the click feeling is good or bad based on the click feeling characteristic value at the boundary of the section, since the operation key is incorporated in the product, the temporary value of the absolute value of the load which is the feature of the single key is temporary. Even if the deterioration is not clear, it is possible to properly judge the quality, and it is possible to realize the automatic inspection in the state where the product is assembled. Further, when the displacement-load function is used, the characteristic value related to the stroke is also used, so that it is possible to make a judgment with higher reliability, and when the time-load function is used, the displacement amount sensor is not required, so that the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of a click feeling inspection device according to a first embodiment of the present invention.

FIG. 2 is a flowchart of data processing of the same embodiment.

FIG. 3 is a displacement-load characteristic curve diagram in the example.

FIG. 4 is a first-order differential characteristic diagram of the displacement-load characteristic curve of FIG.

FIG. 5 is a graph of a Gaussian filter.

FIG. 6 is a basic configuration diagram of a click feeling inspection device according to a second embodiment of the present invention.

FIG. 7 is a flow chart of data processing of the second embodiment of the present invention.

FIG. 8 is a time-load characteristic curve diagram in the example.

9 is a first-order differential characteristic diagram of the time-load characteristic curve of FIG.

FIG. 10 is a basic configuration diagram of a conventional click feeling inspection device.

11A and 11B are characteristic diagrams of the conventional example, FIG. 11A is a displacement-load characteristic curve diagram, and FIG. 11B is a characteristic diagram in which the characteristic curve is approximated by a line segment connecting each characteristic point.

FIG. 12 is a basic configuration diagram of another conventional click feeling inspection apparatus.

13A and 13B are characteristic diagrams of the conventional example, FIG. 13A is a time-load characteristic curve diagram, and FIG. 13B is a characteristic diagram in which the characteristic curve is approximated by a line segment connecting each characteristic point.

[Explanation of symbols]

 1 product to be inspected 2 operation key 3 fingertip of key pressing part 5 pressure sensor (load cell) 9 displacement sensor (differential transformer) 10 click feeling inspection part 11 A / D conversion part 12 function creation part 13 differential processing part 14 interval division Processing unit 15 Characteristic value calculation unit 16 Judgment unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nozomi Ueshiba 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (2)

[Claims] 1. A key pressing unit for pressing an operation key, a sensing unit for detecting a displacement and a load when the operation key is pressed,
A / D conversion unit that A / D-converts the displacement and load detection signals, a differential processing unit that converts the A / D-converted information into a differential function having a differential value of the load with respect to the displacement, and a differential function A section division processing unit that divides into sections of displacement, a click feeling characteristic value calculation unit that calculates a click feeling characteristic value from the divided sections, and whether the operation key is normal by applying the click feeling characteristic value to a predetermined determination formula A click feeling inspection device for an operation key, comprising: a determination unit that determines whether the operation key is clicked. 2. A key pressing unit for pressing an operation key, a sensing unit for detecting a load when the operation key is pressed, an A / D conversion unit for A / D converting a load detection signal, and an A / D. A differential processing unit that differentiates the converted information, a section division processing unit that divides the differential function into sections, a click feeling characteristic value calculation unit that calculates a click feeling characteristic value from the divided sections, and a click feeling characteristic value in advance. A click feeling inspection device for an operation key, comprising: a determination unit that applies a predetermined determination expression to determine whether or not the operation key is normal.