Patent Description:
Conventionally, a measuring device such as a caliper, a micrometer, a digital indicator or the like may have a display device for displaying various information such as a measured value, and a back light for emitting a light to a back of the display device (for example, see <CIT>). When the back light emits a light to the display device, it is easy to read information displayed by the display device in a dark place. <CIT> shows a measuring instrument including a display that displays measurements. The display is provided by an organic electroluminescent display device or an electronic paper including an assembly of organic electroluminescence devices. Since the display is provided by the organic electroluminescent display device or an electronic paper including an assembly of organic electroluminescence devices, visibility of the display can be enhanced. Further, since the display can be used for various measuring instruments in common, the display design can be easily changed and production cost can be reduced. <CIT> shows a measurement device comprising a main scale; a first slider having a contact part with the target to be measured, and capable of sliding in a longitudinal direction of the main scale to the main scale; and a notification part for notifying of whether measurement force for pressing the target to be measured when the contact part is brought into contact to the target to be measured is a predetermined value or not. <CIT> shows a detecting sensor having a display function of mode switching. The detecting sensor comprises a pressure sensor with a section for detecting pressure, a reference level setting switch for setting a reference value, a switching switch for switching modes, a CPU having a calculation function and a control function, and a section for displaying which receives control signals from the CPU to display a measurement result. Herein the section for displaying has an LCD display plate and a backlight including two types LEDs of a red LED and a green LED. In response to the measurement result, the modes of the pressure sensor are changed, the LEDs are switched on and off, and the display colors of display contents that are displayed on the LCD display plate are switched.

However, even if the back light emits a light to the display device, it may be difficult to read information displayed by the display device in some conditions during obtaining information from the display device, such as an eyesight of a measurer using a measuring device.

In one aspect of the present invention, it is an object to easily obtain various information through a display device of a measuring device. To solve this problem, the present invention provides a measuring device having the features of the respective independent claim. Embodiments are described in the dependent claims.

According to an example that is not encompassed by the claims but useful for understanding the present invention, there is provided a measuring device including: a measured value obtainer; a display device configured to display a measured value obtained by the measured value obtainer; an illumination device configured to emit a light to the display device; a measurement state obtainer configured to obtain information regarding a state in which a measured value is obtained by the measured value obtainer; and an illumination color changer configured to change a color of the light in accordance with a measurement state obtained by the measurement state obtainer.

(First Aspect) A description will be given of a digital indicator <NUM> which is one example of measuring devices in accordance with a first aspect, which is useful for understanding the invention, on the basis of <FIG>. <FIG> illustrates a front view of the digital indicator <NUM>. <FIG> schematically illustrates an internal structure of the digital indicator <NUM>. <FIG> illustrates a display example of a display device (a liquid crystal display device <NUM>) in a case where a normal measurement mode is selected. <FIG> illustrates a display example of the liquid crystal display device <NUM> in a case where a tolerance determination mode is selected. <FIG> illustrates a display example of the liquid crystal display device <NUM> in a case where a maximum-minimum measurement mode is selected.

The digital indicator <NUM> is a measuring device of a digital type. The digital indicator <NUM> has a chassis <NUM> and a spindle <NUM>. The spindle <NUM> acts as a mover having a gauge head 3a provided on an edge of the spindle <NUM>. The spindle <NUM> is capable of sliding with respect to the chassis <NUM>. The gauge head 3a contacts a surface of a measurement object. The chassis <NUM> has a switch <NUM> and an operation button <NUM>. As illustrated in <FIG>, a main controller <NUM>, an encoder <NUM>, a back light controller <NUM>, a back light <NUM> and the liquid crystal display device <NUM> are provided in the chassis <NUM>. The back light <NUM> acts as an illumination device. A measured value obtainer includes the encoder <NUM> together with the spindle <NUM>.

The chassis <NUM> has a window 2a. A parting plate 2b is provided in the window 2a. The parting plate 2b is a transparent board. The liquid crystal display device <NUM> provided in the chassis <NUM> faces the parting plate 2b. The display device includes the liquid crystal display device <NUM> and the parting plate 2b. The back light <NUM> is provided on the back side of the liquid crystal display device <NUM>. The back side of the liquid crystal display device <NUM> is an inner side of the chassis <NUM> compared to the liquid crystal display device <NUM>. The back light <NUM> emits a light to the liquid crystal display device <NUM> from the back side thereof.

The main controller <NUM> makes the encoder <NUM> detect a displacement amount of the spindle <NUM>, in accordance with a signal from the operation button <NUM> or the back light controller <NUM>. The main controller <NUM> makes the liquid crystal display device <NUM> display a measured value or other information. The measured value is calculated on the basis of the detected displacement amount. The main controller <NUM> has a measurement state obtainer 6a and a measurement mode setting section 6b1.

The measurement mode setting section 6b1 sets the measurement mode of the digital indicator <NUM> by operating the operation button <NUM>. In the present aspect, it is possible to select and set a normal measurement mode, a tolerance determination mode and a maximum-minimum measurement mode. In the normal measurement mode, a displacement amount of the spindle <NUM> is measured under a condition that the gauge head 3a contacts the measurement object, and the measured value is displayed. In the tolerance determination mode, it is determined whether the measured result with respect to the measurement object is within a predetermined allowable tolerance. For example, in the tolerance determination mode, it is determined whether the displacement amount of the spindle <NUM> under the condition that the gauge head 3a contacts the measurement object is within the predetermined allowable tolerance. And, the liquid crystal display device <NUM> displays the determination result. In the maximum-minimum measurement mode, at least one of a maximum value and a minimum value of the measured values of the measurement object is measured. For example, in the maximum-minimum measurement mode, the maximum value and the minimum value of the displacement amount of the spindle <NUM> under the condition that the gauge head 3a contacts the measurement object are recorded. And the liquid crystal display device <NUM> displays the recorded values. In the maximum-minimum measurement mode, a difference between the maximum value and the minimum value may be recorded as amplitude. And the liquid crystal display device <NUM> may display the recorded value.

The measurement mode setting section 6b1 gives the measurement state obtainer 6a the measurement mode information indicating which measurement mode is selected, as the information regarding the state in which the measured value is obtained. In the digital indicator <NUM>, the measurement mode information indicating which measurement mode is selected is an example of the information regarding the state in which the measured value is obtained.

The encoder <NUM> has a detection head 7a provided in the spindle <NUM>, and an electromagnetic type scale arranged along a sliding direction of the spindle <NUM>. The scale and the detection head 7a detect the displacement amount of the spindle <NUM> with respect to the chassis <NUM>. The detection head 7a is electrically connected with the main controller <NUM>.

The back light controller <NUM> is electrically connected with the main controller <NUM>. The back light controller <NUM> is electrically connected with the back light <NUM>. The back light controller <NUM> switches the electrical power supply mode to the back light <NUM> by operating the switch <NUM>. The back light controller <NUM> controls turning on of the back light <NUM> and turning off of the back light <NUM>. The digital indicator <NUM> has a battery inside of the chassis <NUM>. When the back light <NUM> receives electrical power from the battery, the back light <NUM> is turned on. The back light <NUM> is electrically connected with the main controller <NUM>.

The back light controller <NUM> has a back-light color changer 8a acting as an illumination color changer to change the color of the back light <NUM>. The back-light color changer 8a changes the color of the back light in accordance with the measurement mode which is set by the measurement mode setting section 6b1.

A description will be given of an example of a combination of the measurement mode which is selected and set, and the color of the back light, on the basis of <FIG> illustrate differences of the color by types of hatching.

<FIG> illustrates the liquid crystal display device <NUM> in a case where the normal measurement mode is selected. When the normal measurement mode is selected, the back light <NUM> illustrated in <FIG> emits a white color light and the liquid crystal display device <NUM> glows white. On the other hand, <FIG> illustrates the liquid crystal display device <NUM> in a case where the tolerance determination mode is selected. When the tolerance determination mode is selected, the back light <NUM> emits a green color light and the liquid crystal display device <NUM> glows green. <FIG> illustrates the liquid crystal display device <NUM> in a case where the maximum-minimum measurement mode is selected. When the maximum-minimum measurement mode is selected, the back light <NUM> emits a blue color light and the liquid crystal display device <NUM> glows blue.

In this manner, the color of the back light <NUM> changes in accordance with the selected measurement mode. Therefore, when the measuring person discriminates the color of the back light <NUM>, the measuring person can immediately know which measurement mode is selected. That is, the measuring person can know which measurement mode is selected even if the measuring person does not read letters or icons displayed on the liquid crystal display device <NUM>.

In the present aspect, the back light <NUM> is set up so that the color of the back light <NUM> changes among the predetermined three colors in accordance with measurement mode. However, the measuring person can freely set the colors of the back light <NUM> corresponding to each measurement mode by operating the operation button <NUM>.

In the first aspect, the description of the digital indicator <NUM> is given. However, other measuring devices having an illumination device for emitting a light to the display device and having a plurality of measurement modes can change the color of the illumination device in accordance with the measurement mode. Other measuring devices are such as a caliper, a micrometer or the like.

(Second Aspect) Next, a description of a second aspect, which is useful for understanding the invention, will be given on the basis of <FIG>. <FIG> illustrates an inner structure of the digital indicator <NUM> in accordance with the second aspect. <FIG> illustrates a display example of the display device (the liquid crystal display device <NUM>) in a case where a moving speed of the spindle <NUM> of the digital indicator <NUM> is excessively small. <FIG> illustrates a display example of the display device (the liquid crystal display device <NUM>) in a case where the moving speed of the spindle <NUM> of the digital indicator <NUM> is adequate. <FIG> illustrates a display example of the display device (the liquid crystal display device <NUM>) in a case where the moving speed of the spindle <NUM> of the digital indicator <NUM> is excessively large. <FIG> illustrates a display example of the display device in which the color of the back light changes in steps in accordance with the moving speed of the spindle <NUM>.

A description will be given of points of the second aspect which are different from those of the first aspect. In the second aspect, the same reference numerals are added to the same structure elements in the figures, as those of the first aspect. The same reference numerals are also added to the same structure elements not illustrated in <FIG>, as those of the first aspect. Detail explanations of the same structure elements are omitted.

The second aspect includes a moving speed calculator 6b2, in addition to the measurement mode setting section 6b1 of the digital indicator <NUM> of the first aspect. The moving speed calculator 6b2 is included in a moving speed detector <NUM> together with the encoder <NUM>. The moving speed detector <NUM> detects the moving speed of the spindle <NUM> of the measured value obtainer. In <FIG>, the measurement mode setting section 6b1 is not illustrated. The moving speed calculator 6b2 may be equipped instead of the measurement mode setting section 6b1.

In concrete, the moving speed detector <NUM> samples a displacement amount of the spindle <NUM> which is detected by the encoder <NUM>. The moving speed detector <NUM> calculates the moving speed of the spindle <NUM>, on the basis of the sampled values. The moving speed detector <NUM> determines whether the moving speed of the spindle <NUM> is excessively small, adequate, or excessively large, by comparing the moving speed with a first threshold determined in advance or a second threshold which is larger than the first threshold. That is, the moving speed detector <NUM> determines that the moving speed is excessively small when the moving speed of the spindle <NUM> is smaller than the first threshold. The moving speed detector <NUM> determines that the moving speed is adequate when the moving speed of the spindle <NUM> is equal to or more than the first threshold and smaller than the second threshold. The moving speed detector <NUM> determines that the moving speed is excessively large when the moving speed of the spindle <NUM> is equal to or more than the second threshold.

As information regarding the state in which the measured values are obtained, the moving speed detector <NUM> supplies information regarding the moving speed of the spindle <NUM> to the measurement state obtainer 6a. The information regarding the moving speed of the spindle <NUM> is an example of the information regarding the state in which the measured values are obtained. The information regarding the moving speed of the spindle <NUM> is also an example of the operation state information regarding the operation state in which the measured value obtainer including the spindle <NUM> obtains the measured values.

When the moving speed of the spindle <NUM> is large, it may not be necessarily possible to appropriately measure the peak. There may be a case where the digital indicator <NUM> has an auto-off function in which the digital indicator <NUM> is automatically turned off when the digital indicator <NUM> is not used, and the auto-off function is used. In this case, the auto-off function may be activated. When the moving speed of the spindle <NUM> is excessively small, the measurement efficiency may be degraded. And so, in the present aspect, the information regarding the moving speed of the spindle <NUM> is obtained. It is determined whether the spindle <NUM> moves with the adequate moving speed. The liquid crystal display device <NUM> displays the determined result.

A description will be given of an example of a combination of the moving speed of the spindle <NUM> and the color of the back light, on the basis of <FIG> illustrate differences of the color by types of hatching.

<FIG> illustrates the liquid crystal display device <NUM> in a case where the moving speed of the spindle <NUM> is excessively low. When the moving speed of the spindle <NUM> is excessively low, the back light <NUM> emits a green color light and the liquid crystal display device <NUM> glows green. On the other hand, <FIG> illustrates the liquid crystal display device <NUM> in a case where the moving speed of the spindle <NUM> is adequate. When the moving speed of the spindle <NUM> is adequate, the back light <NUM> emits a blue color light and the liquid crystal display device <NUM> glows blue. <FIG> illustrates the liquid crystal display device <NUM> in a case where the moving speed of the spindle <NUM> is excessively high. When the moving speed of the spindle <NUM> is excessively high, the back light <NUM> emits a red color light and the liquid crystal display device <NUM> glows red.

In this manner, the color of the back light <NUM> changes in accordance with the moving speed of the spindle <NUM>. Therefore, when the measuring person discriminates the color of the back light <NUM>, the measuring person can immediately know whether the measuring using the digital indicator <NUM> is appropriately performed. The measuring person can change the operation of the digital indicator <NUM> and adjust the moving speed of the spindle <NUM> so that the back light emits the blue light. Thus, it is possible to perform precise measurement using the digital indicator <NUM>.

In this manner, the color of the back light <NUM> indicates the moving speed range of the spindle <NUM>. In <FIG>, all area of the liquid crystal display device <NUM> is illuminated by a single color light. On the other hand, as illustrated in <FIG>, the color of the back light <NUM> may gradually change in accordance with the moving speed of the spindle <NUM>. For example, as illustrated in <FIG>, the liquid crystal display device <NUM> is divided into several areas in the width direction. And, the first area in <FIG> which is a leftmost one is illuminated by a white color light. In the width direction, the second area next to the first area is illuminated by a green color light. The third area next to the second area is illuminated by a blue color light. The fourth area next to the third area is illuminated by a red color light.

When the moving speed of the spindle <NUM> is small, all areas of the liquid crystal display device <NUM> are illuminated by the white color light. When the moving speed gets higher, the second area is illuminated by the green color light. When the moving speed gets further higher, the third area is illuminated by the blue color light. When the moving speed gets further higher, the fourth area is illuminated by the red color light. In this manner, the moving speed of the spindle <NUM> may be indicated by the gradation of the displayed color.

In the present aspect, as one example, the color of the back light <NUM> changes among the four colors in accordance with the moving speed of the spindle <NUM>. However, the measuring person may optionally set the colors of the back light <NUM> by operating the operation button <NUM>.

In the second aspect, the description of the digital indicator <NUM> is given. However, other measuring devices, in which an illumination device for emitting a light to the display device is provided and the gauge head moves during the measurement, can change the color of the illumination device in accordance with the moving speed of the gauge head. Other measuring devices are such as a caliper, a micrometer or the like. The moving speed may be detected by an acceleration sensor.

(Third aspect) A description will be given of a third aspect, which is , on the basis of <FIG>. <FIG> illustrates a part of a caliper <NUM> of a third aspect. <FIG> illustrates an inner structure of a slider <NUM> of the caliper <NUM> of the third aspect. <FIG> illustrates a display example of the display device (the liquid crystal display device <NUM>) in a case where contactors <NUM> and <NUM> of the caliper <NUM> hold the measurement object together with each other. <FIG> illustrates a display example of the display device (the liquid crystal display device <NUM>) in a case where the contactors <NUM> and <NUM> hold the measurement object with an adequate force. <FIG> illustrates a display example of the display device (the liquid crystal display device <NUM>) in a case where the contactors <NUM> and <NUM> hold the measurement object with an excessively large force.

The caliper <NUM> is a digital type measuring device. The caliper <NUM> has a main scale <NUM>, the slider <NUM> and an encoder <NUM>. The slider <NUM> acts as a mover which is capable of relatively moving with respect to the main scale <NUM>. The encoder <NUM> detects a displacement amount of the slider <NUM> with respect to the main scale <NUM>. The measured value obtainer includes the main scale <NUM>, the slider <NUM> and the encoder <NUM>. The main scale <NUM> has a first measuring jaw <NUM> which is provided on one edge portion of the main scale <NUM> in a longitudinal direction of the main scale <NUM>. The contactor <NUM> for contacting the measurement object is provided on an edge portion of the first measuring jaw <NUM>. The slider <NUM> has a chassis <NUM> and a second measuring jaw <NUM>. The second measuring jaw <NUM> is provided on one edge of the chassis <NUM> and faces the first measuring jaw <NUM> of the main scale <NUM>. The contactor <NUM> is provided on an edge portion of the second measuring jaw <NUM> and faces the contactor <NUM> of the first measuring jaw <NUM>.

A first strain gauge 211a and a second strain gauge 211b are provided on a root portion of the first measuring jaw <NUM>. The first strain gauge 211a is provided on a face facing the second measuring jaw <NUM>. The second strain gauge 211b is provided on a face opposite to the face on which the first strain gauge 211a is provided. A third strain gauge 221a and a fourth strain gauge 221b are provided on a root portion of the second measuring jaw <NUM>. The third strain gauge 221a is provided on a face facing the first measuring jaw <NUM>. The fourth strain gauge 221b is provided on a face opposite to the face on which the third strain gauge 221a is provided. The location of the first strain gauge 211a, the second strain gauge 211b, the third strain gauge 221a and the fourth strain gauge 221b of <FIG> is one example. The location is not limited to <FIG> and may be arbitrarily changed.

The encoder <NUM> includes a scale <NUM> and a detection head <NUM>. The scale <NUM> is an electromagnetic type scale provided along a longitudinal direction of the main scale <NUM>. The detection head <NUM> is included in the slider <NUM>. The scale <NUM> and the detection head <NUM> detect a displacement amount of the slider <NUM> with respect to the main scale <NUM>, together with each other. The encoder <NUM> acts as a part of the measured value obtainer, together with the contactors <NUM> and <NUM>.

As illustrated in <FIG>, the chassis <NUM> of the slider <NUM> has a switch <NUM> and an operation button <NUM>. The chassis <NUM> houses a main controller <NUM>, the detection head <NUM> acting as a part of the encoder <NUM>, a back light controller <NUM>, a back light <NUM> acting as an illumination device, and a liquid crystal display device <NUM>.

The chassis <NUM> has a window 24a. A parting plate 24b is provided in the window 24a. The parting plate 24b is a transparent board. The liquid crystal display device <NUM> provided in the chassis <NUM> faces the parting plate 24b. The display device includes the liquid crystal display device <NUM> and the parting plate 24b.

The main controller <NUM> controls the encoder <NUM> in accordance with a signal from the operation button <NUM> or the back light controller <NUM>. In accordance with the control, the encoder <NUM> detects a displacement amount of the slider <NUM> with respect to the main scale <NUM>. The main controller <NUM> makes the liquid crystal display device <NUM> digitally show the measured value calculated based on the detected displacement amount or other information. The main controller <NUM> has a measurement state obtainer 27a and a force calculator 27b1. The force calculator 27b1 is electrically connected to the first strain gauge 211a, the second strain gauge 211b, the third strain gauge 221a and the fourth strain gauge 221b.

A force detector <NUM> includes the force calculator 27b1 together with the first strain gauge 211a, the second strain gauge 211b, the third strain gauge 221a and the fourth strain gauge 221b. The force detector <NUM> detects the force applied to the contactors <NUM> and <NUM> of the measured value obtainer.

That is, the force detector <NUM> detects the force applied to the contactors <NUM> and <NUM>, from the strain amount of the first measuring jaw <NUM> and the strain amount of the second measuring jaw <NUM> during holding the measurement object by the contactors <NUM> and <NUM>. It is possible to determine whether the measurement object is held by an adequate force, by detecting the force applied to the contactors <NUM> and <NUM>. The force detector <NUM> determines whether the force applied to the measurement object by the contactors <NUM> and <NUM> is adequate, by comparing the force applied to the contactors <NUM> and <NUM> with a threshold defined in advance. That is, the force detector <NUM> determines that the force is adequate when the force applied to the contactors <NUM> and <NUM> is smaller than the threshold. The force detector <NUM> determines that the force is excessively large when the force applied to the contactors <NUM> and <NUM> is equal to or more than the threshold.

The force detector <NUM> gives the measurement state obtainer 27a the information regarding the force applied to the contactors <NUM> and <NUM> detected by the force detector <NUM>, as the information regarding the state in which the measured value is obtained. The information regarding the force applied to the contactors <NUM> and <NUM> is an example of the information regarding the state in which the measured values are obtained. The information regarding the force applied to the contactors <NUM> and <NUM> is also an example of operation state information regarding the operation state in which the measured value obtainer including the contactors <NUM> and <NUM> obtains the measured values.

The detection head <NUM> is electrically connected with the main controller <NUM>. The back light controller <NUM> is electrically connected with the main controller <NUM>. The back light controller <NUM> is also electrically connected with the back light <NUM>. The back light controller <NUM> switches the state of supplying electrical power to the back light <NUM>, by operating the switch <NUM>. Thus, the back light controller <NUM> controls turning-on and turning-off of the back light <NUM>. These functions are the same as those of the first aspect.

The back light controller <NUM> has a back light-color changer 28a acting as an illumination color changer for changing the color of the back light <NUM>. The back light-color changer 28a changes the color of the back light in accordance with the force applied to the contactors <NUM> and <NUM>.

In this manner, the information regarding the force applied to the contactors <NUM> and <NUM> is obtained, because when the holding force of the contactors <NUM> and <NUM> is excessively large, the measurement object may be deformed and the precise measurement of the size may not be necessarily performed. And so, in the present aspect, it is determined whether the force applied to the contactors <NUM> and <NUM> is adequate or not. And, the liquid crystal display device <NUM> displays the determined result.

A description will be given of an example of a combination of the force applied to the contactors <NUM> and <NUM> and the color of the back light, on the basis of <FIG> illustrate the colors with use of types of hatching.

<FIG> illustrates the liquid crystal display device <NUM> before the contactors <NUM> and <NUM> hold the measurement object. Before the contactors <NUM> and <NUM> hold the measurement object, the back light <NUM> of <FIG> emits a green color light and the liquid crystal display device <NUM> glows green. On the other hand, <FIG> illustrates the liquid crystal display device <NUM> in a case where the measurement object is held by the contactors <NUM> and <NUM> with an adequate force. When the contactors <NUM> and <NUM> hold the measurement object with the adequate force, the back light <NUM> of <FIG> emits a blue color light and the liquid crystal display device <NUM> glows blue. <FIG> illustrates the liquid crystal display device <NUM> in a case where the contactors <NUM> and <NUM> hold the measurement object with an excessively large force. When the contactors <NUM> and <NUM> hold the measurement object with the excessively large force, the back light <NUM> emits a red color light and the liquid crystal display device <NUM> glows red.

In this manner, the color of the back light <NUM> changes in accordance with the force applied to the contactors <NUM> and <NUM>. In other word, the color of the back light <NUM> changes in accordance with the force with which the contactors <NUM> and <NUM> hold the measurement object. Therefore, when the measuring person discriminates the color of the back light <NUM>, the measuring person can immediately know whether the measuring using the caliper <NUM> is appropriately performed or not. The measuring person may change the operation of the caliper <NUM> in accordance with the color of the back light <NUM> and operate the slider <NUM> so that the color of the back light <NUM> is blue. It is therefore possible to perform precise measuring using the caliper <NUM>.

In this manner, in the present aspect, the color of the back light <NUM> indicates the force with which the contactors <NUM> and <NUM> hold the measurement object (the force applied to the contactors <NUM> and <NUM>). However, in <FIG>, a single color light is emitted to all area of the liquid crystal display device <NUM>. On the other hand, the color of the back light <NUM> may gradually change in accordance with the force applied to the contactors <NUM> and <NUM>.

In the present aspect, as one example, the color of the back light <NUM> changes among the three colors in accordance with the force applied to the contactors <NUM> and <NUM>. However, the measuring person may optionally set the colors of the back light <NUM> by operating the operation button <NUM>.

In the third aspect, the description of the caliper <NUM> is given. However, other measuring devices, in which an illumination device for emitting a light to the display device is provided and the measurement object is held by contactors during the measuring, can change the color of the illumination device in accordance with the force applied to the contactors. Other measuring devices are such as a micrometer or the like.

(Fourth aspect) Next, a description will be given of a fourth aspect, which is useful for understanding the invention, on the basis of <FIG>. <FIG> illustrates an inner structure of the slider <NUM> of the caliper <NUM> of the fourth aspect. <FIG> illustrates a display example of the display device (the liquid crystal display device <NUM>) in a case where an impact is not applied to the caliper <NUM>. <FIG> illustrates a display example of the liquid crystal display device <NUM> in a case where an impact is applied to the caliper <NUM>. <FIG> illustrates an accumulated evaluation of an impact history of the caliper <NUM>. <FIG> illustrates a display example of the liquid crystal display device <NUM> in a case where the impact applied to the caliper <NUM> is small. <FIG> illustrates a display example of the liquid crystal display device <NUM> in a case where there is a history of the impact applied to the caliper <NUM> but the impact does not influence on the measurement. <FIG> illustrates a display example of the liquid crystal display device <NUM> in a case where there is a history in which the impact influencing on the measurement is applied to the caliper <NUM>.

A description will be given of points of the fourth aspect which are different from those of the third aspect. In the fourth aspect, the same reference numerals are added to the same structure elements in the figures, as those of the third aspect. The same reference numerals are also added to the same structure elements not illustrated in <FIG>, as those of the third aspect. Detail explanations of the same structure elements are omitted.

As illustrated in <FIG>, in the fourth aspect, an impact determiner 27b2 is provided in addition to the force calculator 27b1 of the caliper <NUM> of the third aspect. The impact determiner 27b2 is included in an impact detector <NUM> together with an accelerator sensor <NUM>. The impact detector <NUM> detects the impact applied to the main scale <NUM>, the slider <NUM> and the encoder <NUM> of the measured value obtainer. The impact determiner 27b2 is electrically connected with an impact history memory <NUM>. When the impact determiner 27b2 determines that the impact is applied, the impact history memory <NUM> stores the detected value of the accelerator sensor <NUM> at the impact. In <FIG>, the force calculator 27b1 is omitted. The impact determiner 27b2 may be provided instead of the force calculator 27b1.

In concrete, the impact detector <NUM> detects an impact from the accelerator sensor <NUM> when the caliper <NUM> hits against a wall or falls to a floor. The value regarding the detected impact is used for the determination whether the caliper <NUM> can perform adequate measuring.

The impact detector <NUM> gives the measurement state obtainer 27a the information regarding the impact applied to the encoder <NUM> or the like of the measured value obtainer, as the information regarding the state in which the measured value is obtained. The information regarding the impact applied to the encoder <NUM> or the like is an example of the information regarding the state in which the measured value is obtained. The information regarding the impact applied to the encoder <NUM> or the like is also an example of the operations state information regarding the operation state in which the measured value obtainer including the encoder <NUM> obtains the measured value.

In this manner, the information regarding the impact applied to the measured value obtainer is obtained. This is because the encoder <NUM> is damaged and the accurate measuring may not be necessarily performed, when the impact is applied to the encoder <NUM>. This is also because the main scale <NUM> or the slider <NUM> is distorted and the accurate measuring may not be necessarily performed, when the impact is applied to the caliper <NUM>. In the present aspect, when the accelerator sensor <NUM> detects an impact applied to the caliper <NUM> which is larger than a predetermined impact, the liquid crystal display device <NUM> displays the fact that the caliper <NUM> is subjected to the impact.

A description will be given of an example of the color of the back light of a case where no impact is applied to the caliper <NUM> and a case where an impact is applied to the caliper <NUM>, on the basis of <FIG>. In <FIG>, the type of the hatching indicates the colors.

<FIG> illustrates the liquid crystal display device <NUM> in the case where no impact is applied to the caliper <NUM>. When no impact is applied to the caliper <NUM>, the back light <NUM> emits a white color light and the liquid crystal display device glows white. On the other hand, <FIG> illustrates the liquid crystal display device <NUM> in the case where the impact is applied to the caliper <NUM>. That is, <FIG> illustrates the liquid crystal display device <NUM> in the case where the impact determiner 27b2 determines that the impact is applied to the caliper <NUM>. When the impact determiner 27b2 determines that the impact is applied to the caliper <NUM>, the back light <NUM> emits a red color light to the liquid crystal display device <NUM> and the liquid crystal display device <NUM> glows red. A threshold of the impact for changing the color of the back light <NUM> to red is determined in advance. The threshold is a value at which the impact influences on the accurate measurement with use of the caliper <NUM> even if only one impact is applied to the caliper <NUM>.

In this manner, the color of the back light <NUM> changes when an impact is applied to the caliper <NUM>. Therefore, when the measuring person discriminates the color of the back light <NUM>, the measuring person can immediately know whether it is possible to perform the accurate measuring with use of the caliper <NUM>. For example, when the liquid crystal display device <NUM> glows red, the measuring person continues the measuring by using another caliper <NUM> which is prepared as a spare one. The measuring person can repair the caliper to which the impact has been applied.

The caliper <NUM> of the present aspect has the accelerator sensor <NUM> and can determine whether an impact is applied to the caliper <NUM> on the basis of the measured value of the accelerator sensor <NUM>. It is thought that even if a single impact does not degrade the accurate measuring with use of the caliper <NUM>, the measuring with use of the caliper <NUM> may be degraded when a plurality of impacts are applied to the caliper <NUM>. And so, the caliper <NUM> determines the condition of the caliper <NUM> by performing the accumulated evaluation of the past impact on the basis of the impact history. And, the caliper <NUM> displays the determined results in steps with use of the back light colors.

As illustrated in <FIG>, a first threshold and a second threshold are determined with respect to the evaluation of the impact history. The evaluation of the impact history is made on the basis of the history stored in a movement history memory <NUM> of <FIG>. The evaluation of the impact history is classified into three phases by the first threshold and the second threshold.

When the accumulated evaluation of the impact history does not reach the first threshold, it is evaluated that the impact is small. Even if the caliper <NUM> is normally used, a slight impact may occur. When the accumulated evaluation of the impact history is smaller than the first threshold and the impact history is negligible in the measuring, it is possible to continuously use the caliper <NUM>.

When the accumulated evaluation of the impact history is between the first threshold and the second threshold, it is evaluated that there is a history of the impact but the history is negligible in the measuring. When the impact applied to the caliper <NUM> is accumulated, it is thought that the impact gradually influences on the measuring. When the accumulated evaluation of the impact history is between the first threshold and the second threshold, it may not be necessarily possible to perform the accurate measuring. However, the maintenance of the caliper <NUM> is recommended.

When the accumulated evaluation of the impact history exceeds the second threshold, it is evaluated that there is a history of an impact influencing on the accuracy of the measuring. In this case, the measuring person may repair the caliper <NUM> to which the impact is applied and continues measuring with use of another caliper <NUM> which is prepared as a spare.

A description will be given of the accumulated evaluation of the impact history and an example of the combination of the back light colors, on the basis of <FIG> illustrate a difference of colors with use of types of hatching.

<FIG> illustrates the liquid crystal display device <NUM> in a case where the accumulated evaluation of the impact history is smaller than the first threshold. When the accumulated evaluation of the impact history is smaller than the first threshold, the back light <NUM> of <FIG> emits a white color to the liquid crystal display device <NUM> and the liquid crystal display device <NUM> glows white. On the other hand, <FIG> illustrates the liquid crystal display device <NUM> in a case where the accumulated evaluation of the impact history is between the first threshold and the second threshold. When the accumulated evaluation of the impact history is between the first threshold and the second threshold, the back light <NUM> emits a blue color light to the liquid crystal display device <NUM> and the liquid crystal display device <NUM> glows blue. <FIG> illustrates the liquid crystal display device <NUM> in a case where the accumulated evaluation of the impact history is larger than the second threshold. When the accumulated evaluation of the impact history is larger than the second threshold, the back light <NUM> emits a red color light to the liquid crystal display device <NUM> and the liquid crystal display device <NUM> glows red.

In this manner, the color of the back light <NUM> changes in accordance with the accumulated evaluation of the impact history. Therefore, when the measuring person discriminates the color of the back light <NUM>, the measuring person can immediately know whether it is possible to perform the adequate measuring with use of the caliper <NUM>. The measuring person can adequately take measures in accordance with the color of the back light <NUM>.

The present realization can be applied to other settings of colors and other measuring devices, as well as other realizations.

(Fifth aspect) Next, a description will be given of a fifth aspect on the basis of <FIG>. <FIG> illustrates an inner structure of the slider <NUM> of the caliper <NUM> of the fifth aspect. <FIG> illustrates a display example of the display device (the liquid crystal display device <NUM>) in a case where maintenance of the caliper <NUM> is not needed. <FIG> illustrates a display example of the display device in a case where the maintenance of the caliper <NUM> is needed. <FIG> illustrates evaluation of a movement distance history of the slider <NUM>. <FIG> illustrates a display example of the display device in a case where the maintenance of the caliper <NUM> is not needed. <FIG> illustrates a display example of the display device in a case where the maintenance of the caliper <NUM> is recommended. <FIG> illustrates a display example of the display device in a case where the maintenance of the caliper <NUM> is needed.

A description will be given of points of the fifth aspect which are different from those of the third aspect. In the fifth aspect, the same reference numerals are added to the same structure elements in the figures, as those of the third aspect. The same reference numerals are also added to the same structure elements not illustrated in <FIG>, as those of the first aspect. Detail explanations of the same structure elements are omitted.

As illustrated in <FIG>, in the fifth aspect, a movement distance calculator 27b3 is provided in addition to the force calculator 27b <NUM> of the caliper <NUM> of the third aspect. The movement distance calculator 27b3 is included in a movement distance measurer <NUM> together with the detection head <NUM>. The movement distance measurer <NUM> measures the movement distance of the slider <NUM>. The movement distance calculator 27b3 is electrically connected with the movement history memory <NUM>. The movement history memory <NUM> stores the movement distance of the slider <NUM> calculated by the movement distance calculator 27b3. In <FIG>, the force calculator 27b1 is omitted. The movement distance calculator 27b3 may be provided instead of the force calculator 27b1.

In concrete, the movement distance measurer <NUM> measures a distance the slider <NUM> slides with respect to the main scale <NUM>. When the slider <NUM> repeats the sliding with respect to the main scale <NUM>, the slider <NUM> needs maintenance because rattling occurs in the slider <NUM>. The movement distance of the slider <NUM> is used for determining whether the maintenance of the caliper <NUM> is necessary or not.

The movement distance measurer <NUM> gives the measurement state obtainer 27a information regarding the movement distance of the slider <NUM> (mover) of the measured value obtainer, as the information regarding the state in which the measured value is obtained. The information regarding the movement distance of the slider <NUM> is an example of the information regarding the state in which the measured value is obtained. The information regarding the movement distance of the slider <NUM> is also an example of the information regarding the operations state in which the measured value obtainer including the slider <NUM> obtains the measured value.

In this manner, the information regarding the movement distance of the slider <NUM> is obtained in order to detect the possibility that the rattling between the slider <NUM> and the main scale <NUM> caused by frictional wear causes degradation of the measuring if the distance the slider <NUM> slides with respect to the main scale <NUM> gets longer. In the present aspect, when the movement distance of the slider <NUM> exceeds a predetermined value, the liquid crystal display device <NUM> displays the results that the movement distance exceeds the predetermined value.

A description will be given of an example of the back light colors in a case where the maintenance of the caliper <NUM> is not needed and in a case where the maintenance of the caliper <NUM> is needed, on the basis of <FIG> illustrate a difference of colors with use of types of hatching.

<FIG> illustrates the liquid crystal display device <NUM> in a case where the movement distance of the slider <NUM> is not large and the maintenance of the caliper <NUM> is not needed. When the maintenance of the caliper <NUM> is not needed, the back light <NUM> of <FIG> emits a white color light to the liquid crystal display device <NUM> and the liquid crystal display device <NUM> glows white. On the other hand, <FIG> illustrates the liquid crystal display device <NUM> in a case where the movement distance of the slider <NUM> gets larger and the maintenance of the caliper <NUM> is needed. When the maintenance of the caliper <NUM> is needed, the back light <NUM> emits a red color light to the liquid crystal display device <NUM> and the liquid crystal display device <NUM> glows red. A threshold of the movement distance for changing the color of the back light <NUM> to red is determined in advance. The threshold is a value at which the accurate measuring of the caliper <NUM> is degraded.

In this manner, the color of the back light <NUM> changes when the movement distance of the slider <NUM> gets larger. Therefore, when the measuring person discriminates the color of the back light <NUM>, the measuring person can know whether it is possible to perform the accurate measuring with use of the caliper <NUM>. For example, when the liquid crystal display device <NUM> glows red, the measuring person continues the measuring by using another caliper <NUM> which is prepared as a spare one. The measuring person can repair the caliper of which the movement distance is large.

It is thought that the influence of the movement distance of the slider <NUM> on the accurate measuring with use of the caliper <NUM> gradually appears as the movement distance is accumulated. And so, the caliper <NUM> of the present aspect determines the condition of the caliper <NUM> by evaluating the movement distance history. And, the determined result is displayed in steps with use of the back light color.

As illustrated in <FIG>, a first threshold and a second threshold are determined with respect to the evaluation of the movement distance history. The evaluation of the movement history is made on the basis of the history stored in the movement history memory <NUM> of <FIG>. The evaluation of the movement distance history is classified into three phases by the first threshold and the second threshold.

When the evaluation of the movement distance history does not reach the first threshold, it is evaluated that the maintenance is not needed. When it is thought that the movement distance of the slider <NUM> is negligible in the measuring, it is possible to continue the using of the caliper <NUM>.

When the evaluation of the movement distance history is between the first threshold and the second threshold, it is evaluated that the maintenance is recommended. When the movement distance of the slider <NUM> gets larger, it is thought that the movement distance gradually influences on the accuracy of the measuring. When the evaluation of the movement distance history is between the first threshold and the second threshold, it may not be necessarily possible to perform the accurate measuring. However, the maintenance of the caliper <NUM> is recommended before the measuring is degraded.

When the evaluation of the movement distance history exceeds the second threshold, it is evaluated that the maintenance is needed. In this case, the caliper <NUM> is repaired, and the measuring person continues the measuring with use of another caliper <NUM> which is prepared as a spare.

A description will be given of the evaluation of the movement distance history and the combination of the back light colors, on the basis of <FIG> illustrates a difference of colors with use of types of hatching.

<FIG> illustrates the liquid crystal display device <NUM> in a case where the evaluation of the movement distance history is smaller than the first threshold. When the evaluation of the movement distance history is smaller than the first threshold, the back light <NUM> of <FIG> emits a white color light to the liquid crystal display device <NUM> and the liquid crystal display device <NUM> glows white. On the other hand, <FIG> illustrates the liquid crystal display device <NUM> in a case where the evaluation of the movement distance history is between the first threshold and the second threshold. When the evaluation of the movement distance history is between the first threshold and the second threshold, the back light <NUM> emits a blue color light to the liquid crystal display device <NUM> and the liquid crystal display device <NUM> glows blue. <FIG> illustrates the liquid crystal display device <NUM> in a case where the evaluation of the movement distance history is larger than the second threshold. When the evaluation of the movement distance history is larger than the second threshold, the back light <NUM> emits a red color light and the liquid crystal display device <NUM> glows red.

In this manner, the color of the back light <NUM> changes in accordance with the evaluation of the movement distance history. Therefore, when the measuring person discriminates the color of the back light <NUM>, the measuring person can immediately know whether it is possible to perform the adequate measuring with use of the caliper <NUM>. The measuring person can adequately take measures in accordance with the color of the back light <NUM>.

The present aspect can be applied to other settings of colors and other measuring devices, as well as other realizations.

The measuring device of the above-mentioned aspect changes the light color of the back light (the illumination device) in accordance with the measurement state obtained by the measurement state obtainer. Therefore, the measuring person can understand the measurement state even if the measuring person does not read letters or the like displayed on the liquid crystal display device (the display device).

The measuring device of the above-mentioned aspect changes the light color of the back light in accordance with the selected measurement mode information. Therefore, the measuring person can immediately understand which measurement mode is selected.

The measuring device of the above-mentioned aspect changes the light color of the back light in accordance with the operation state information regarding the operations state in which the measured value obtainer obtains the measured value. Therefore, the measuring person can immediately understand the operation state of the measuring device and correct the operation method.

The measuring device of the above-mentioned aspect changes the light color of the back light in accordance with the usage history regarding the usage history of the measured value obtainer. Therefore, the measuring person can immediately understand the state of the measuring device and repair the measuring device.

Claim 1:
A measuring device (<NUM>) comprising:
a measured value obtainer (<NUM>,<NUM>);
a display device (<NUM>) configured to display a measured value obtained by the measured value obtainer;
an illumination device (<NUM>) configured to emit a light to the display device;
a movement distance measurer (<NUM>) configured to measure a movement distance of a mover of the measured value obtainer (<NUM>, <NUM>);
a measurement state obtainer (27a) configured to obtain movement distance history information regarding a state in which a measured value is obtained by the measured value obtainer by evaluating the movement distance history; and
an illumination color changer (8a) configured to change a color of the light in accordance with the movement distance history information obtained by the measurement state obtainer, so that the illumination color changer changes the color of the light in steps in accordance with a length of a movement distance of the mover.