JP7478079B2 - Constant Temperature Measurement System - Google Patents

Description

The present invention relates to a constant temperature measurement system that measures the shape and dimensions of a workpiece.

In metal processing such as forging and cutting, processing accuracy on the order of microns may be required, but typically the work expands due to heat generated during processing. For this reason, dimensions are often measured after cooling to a specified temperature. Even in measuring devices that perform dimensional measurements, dial gauges and linear gauges that measure by contacting a gauge head with the object being measured can have the supports that support the dial gauge expand or contract due to changes in the ambient temperature of the device. For this reason, it is desirable to install such measuring devices in a room where the temperature is controlled by an air conditioning unit.

One example of a device that cools a workpiece to a predetermined temperature after machining is the "constant temperature bath" disclosed in Patent Document 1 below. However, because constant temperature baths tend to be large and complex, depending on the manufacturing site, it may be difficult to install one due to work space limitations. Also, in cases where a manufacturing line is equipped with measuring devices that measure dimensions, it is necessary to control the temperature of the entire manufacturing line using air conditioning equipment, but it may not be practical to install such air conditioning equipment.

As an example of a device that can cool a workpiece or the like after processing to a predetermined temperature while being relatively compact in size, there is the "precision constant temperature plate" disclosed in the following Patent Document 2. This precision constant temperature plate is configured to cool the metal workpiece placed on the stone plate by connecting an electronic cooler capable of cooling the stone plate on which the metal workpiece or the like can be placed, and a temperature sensor embedded in the bottom of the stone plate to a temperature regulator. The size of the stone plate is 40 cm on each side, and 20 mm to 30 mm thick (Patent Document 2; paragraph 0006).

JP 2018-177459 A Japanese Patent Application Laid-Open No. 9-126703

However, the precision constant temperature platen disclosed in Patent Document 2 has a structure in which a temperature sensor is embedded under the stone plate, as described above. Therefore, it is difficult to directly measure the temperature of the metal workpiece, such as the workpiece, using this precision constant temperature platen. In addition, the temperature of a stone plate, which generally has a larger heat capacity than a metal plate, changes slowly. Therefore, while a certain degree of temperature control is possible, there is a problem in that achieving precise temperature management poses high technical hurdles.

The present invention has been made to solve the above-mentioned problems, and aims to provide a constant temperature measurement system that can measure the shape and dimensions of a measurement object that is precisely temperature-controlled so as to be less susceptible to the effects of thermal expansion and contraction, without the need for large-scale equipment.

In order to achieve the above object, the technical means of claim 1 described in the claims is adopted. According to this means, a measuring device, a first cold/hot unit, a first temperature sensor, a second cold/hot unit, a second temperature sensor, a third temperature sensor, and a temperature controller are included. The first temperature sensor measures the temperature of the master work and outputs master temperature information. The second temperature sensor measures the temperature of the measuring device and outputs measuring device temperature information. The third temperature sensor measures the temperature of the measured workpiece to be measured and outputs workpiece temperature information. The temperature controller controls the output temperature of the first cold/hot unit so that the temperature of the master work matches the temperature of the measured workpiece as temperature matching control, and controls the output temperature of the second cold/hot unit so that the temperature of the measuring device matches the temperature of the measured workpiece. As a result, even if the temperatures of the master workpiece and the measured workpiece are different, the master workpiece and the measuring device are different, or the temperatures of the measured workpiece and the measuring device are different (hereinafter referred to as "when the temperatures of the three things such as the master workpiece are different"), the master workpiece and the measuring device are cooled or heated, and the temperatures of the master workpiece and the measuring device become the same as the temperature of the measured workpiece. Furthermore, since each temperature sensor measures the temperature of the master work, the workpiece to be measured, and the measuring device, it is possible to measure with higher accuracy than when measuring the temperature of the first cooling/heating unit, etc. Therefore, it is possible to align the temperatures of these three with high accuracy without providing a cooling/heating unit to cool or heat the workpiece to be measured. In this specification, the output temperature of ○○○ refers to the temperature when the temperature of ○○○ itself or an object thermally coupled to ○○○ drops or rises due to the heat absorption or heat generation of ○○○ (○○○ can be any name that is the same).

In order to achieve the above object, the technical means of claim 2 described in the claims is adopted. According to this means, the measuring device includes a measuring device, a first cold/hot unit, a first temperature sensor, a second cold/hot unit, a second temperature sensor, a third temperature sensor, and a temperature controller. The first temperature sensor measures the temperature of the master work and outputs master temperature information. The second temperature sensor measures the temperature of the measuring device and outputs measuring device temperature information. The third temperature sensor measures the temperature of the measured work and outputs work temperature information. The temperature controller controls the output temperature of the first cold/hot unit as temperature matching control so that the temperature of the master work matches the temperature of the measuring device, and controls the output temperature of the second cold/hot unit so that the temperature of the measured work matches the temperature of the measuring device. As a result, even if the temperatures of the three, such as the master work, are different, the master work and the measured work are cooled or heated, so that the temperatures of the master work and the measured work become the same as the temperature of the measuring device. In addition, since each temperature sensor measures the temperature of the master work, the measured work, and the measuring device, it is possible to measure with higher accuracy than when measuring the temperature of the first cold/hot unit, etc. This makes it possible to align these three temperatures with high precision without having to install a cooling/heating unit in the measuring device.

In order to achieve the above object, the technical means of claim 3 described in the claims is adopted. According to this means, a measuring device, a first cold/hot unit, a first temperature sensor, a second cold/hot unit, a second temperature sensor, a third cold/hot unit, a third temperature sensor, and a temperature controller are included. The first temperature sensor measures the temperature of the master work and outputs master temperature information. The second temperature sensor measures the temperature of the measuring device and outputs measuring device temperature information. The third temperature sensor measures the temperature of the measured work and outputs work temperature information. The temperature controller controls the output temperatures of the first cold/hot unit, the second cold/hot unit, and the third cold/hot unit as temperature matching control so that the temperatures of the master work, the measured work, and the measuring device each match a predetermined temperature. As a result, even if the temperatures of the three, such as the master work, are different, the master work, the measured work, and the measuring device are cooled or heated, making it possible to match the temperatures of these three to a predetermined temperature with high accuracy.

The technical means of claim 4 and the technical means of claim 5 are also adopted. According to these means, the first cold/hot unit, the second cold/hot unit, and the third cold/hot unit are provided with a Peltier module that is controlled for cooling or heating by a temperature controller. For example, the Peltier module is configured by connecting a plurality of Peltier elements in series and/or parallel. When a predetermined voltage is applied to the Peltier module, it generates heat on one side and absorbs heat on the other side. Then, by reversing the polarity of the applied voltage, it absorbs heat on one side and generates heat on the other side. In other words, by switching the polarity of the applied predetermined voltage, it is possible to make the same Peltier module function as a heat source and a heat absorber. This makes it possible to configure the first to third cold/hot units with one Peltier module, compared to the case where the first cold/hot unit, the second cold/hot unit, and the third cold/hot unit are configured using a heat source and a heat absorber, respectively. Therefore, the first cold/hot unit, the second cold/hot unit, and the third cold/hot unit can be configured simply.

The technical means of claim 6 described in the claims is also adopted. According to this means, the measurement controller further includes a measurement controller, which, in a temperature matching state by temperature matching control, compares the master dimensional information output from the measuring device as dimensional information by measuring the master workpiece with the workpiece dimensional information output from the measuring device as dimensional information by measuring the measured workpiece, and outputs the dimensional error between the two, or determines whether the dimensional error is within a predetermined range and outputs the result. This makes it possible to automate inspection of the shape and dimensions of the measured workpiece. Therefore, without installing large-scale equipment, it is possible to measure the shape and dimensions of the measured object that is precisely temperature-controlled so as to be less susceptible to the effects of thermal expansion and thermal contraction, and to automatically inspect the shape and dimensions of the measured workpiece.

The master dimension information and workpiece dimension information are output from the measuring device in a temperature coincidence state due to the temperature coincidence control of claims 1 to 5. When the measuring device measures the shape and dimensions of the master workpiece or the measured workpiece, the timing at which the measuring device measures the shape and dimensions of the master workpiece and the timing at which the measuring device measures the shape and dimensions of the measured workpiece may be the same (simultaneous) or different (different) as long as the temperature of the master workpiece or the measured workpiece coincides with a specific temperature (temperature coincidence state). The specific temperature is the "temperature of the measured workpiece" in claim 1, the "temperature of the measuring device" in claim 2, and the "predetermined temperature" in claim 3. Therefore, "in a temperature coincidence state due to temperature coincidence control" refers to a situation in which the temperatures of the master workpiece, the measured workpiece, and the measuring device coincide, and does not refer to the coincidence (simultaneity) of the measurement timing of the master workpiece or the measured workpiece by the measuring device.

The present invention makes it possible to measure the shape and dimensions of a test object whose temperature is precisely controlled so that it is not easily affected by thermal expansion or contraction, without the need for large-scale equipment.

1 is a block diagram showing an example of the configuration of a constant temperature measurement system according to a first embodiment of the present invention. 2A and 2B are schematic oblique views showing an example of the configuration of a cooling/heating device included in the constant temperature measurement system of the first embodiment, where FIG. 2A is a view before the measured work or master work is set, and FIG. 2B is a view after the measured work or master work is set. 3A and 3B are schematic oblique views showing another example of the configuration of a cooling/heating device included in the constant temperature measurement system of the first embodiment, where FIG. 3A is a view from diagonally above, and FIG. 3B is a view of a cross section cut in the longitudinal direction as viewed from the short side. 5 is a flowchart showing a flow of a constant temperature control process executed by a temperature controller in the constant temperature measurement system of the first embodiment. 5 is a flowchart showing a flow of a cooling/heating control process executed by a temperature controller in the constant temperature measurement system of the first embodiment. FIG. 11 is a block diagram showing an example of the configuration of a constant temperature measurement system according to a second embodiment of the present invention. 7A and 7B are flowcharts showing the flow of information processing executed by a measurement controller in the constant temperature measurement system of the second embodiment, where FIG. 7A is a flowchart of measurement control processing, FIG. 7B is a flowchart of dimension measurement processing shown in FIG. 7A, and FIG. 7C is a flowchart of OK/NG processing shown in FIG. 7A.

Hereinafter, embodiments of the constant temperature measurement system of the present invention will be described with reference to the drawings.
[First embodiment]
A first embodiment of a constant temperature measurement system of the present invention will be described with reference to Figures 1 to 5. As shown in Figure 1, a constant temperature measurement system 10 of this first embodiment is a system for maintaining, for example, a measured workpiece W, a master workpiece M, and a measuring device 20 at a specific temperature, and is mainly composed of a measuring device 20, cooling and heating devices 40, 50, temperature sensors 61 to 63, and a temperature controller 70. In this first embodiment, the measured workpiece W and the master workpiece M are, for example, metallic shaft parts having a shape in which cylindrical bodies of different diameters are stacked coaxially, and are made of the same material.

The measuring device 20 is an instrument for measuring the shape and dimensions of the object X (e.g., the workpiece W or the master workpiece M), and includes a measuring table 21 having a flat surface 21a at the top, a cylindrical support 23 that rises vertically from the measuring table 21, a bracket 25 attached to the support 23 so as to be movable up and down relative to the measuring table 21, and a measuring unit 30 held by the bracket 25. The combination of the measuring table 21, support 23, and bracket 25 is called a "stand," and the measuring table 21 is sometimes called a "table." In this first embodiment, the support 23 is made of metal. The object X is placed on the flat surface 21a of the measuring table 21, and the shape and dimensions are measured by the measuring unit 30.

The measuring unit 30 is, for example, a dial gauge, and is a measuring device that is composed of a main body 31, a spindle 32, a measuring element 33, a display unit 35, etc., and can precisely measure the amount of movement (protrusion amount) of the spindle 32, which freely protrudes from the main body 31, as a linear distance. The tip of the spindle 32 is provided with a measuring element 33 that contacts the object to be measured X. The rear end of the spindle 32 is provided with a rack gear of a rack-and-pinion (not shown) that converts the linear motion of the spindle 32 into rotational motion. The pinion gear is connected to the display unit 35 of the main body 31 via a magnifying transmission mechanism that magnifies the movement, etc., and is configured to rotate the pointer 35a. These gears, the magnifying transmission mechanism, etc. are housed in the main body 31.

In this first embodiment, the measurement unit 30 is attached to the bracket 25 of the stand (measurement table 21, support 23, bracket 25) of the measuring device 20 for use. Specifically, when the probe 33 is brought into contact with the object to be measured X or the like, the amount of movement of the spindle 32 is measured by reading the scale (not shown) indicated by the pointer 35a of the display unit 35. Therefore, for example, the dimensional error of the measured work W relative to the master work M can be measured as the amount of movement of the spindle 32, or the size (width or height) of a portion of the measured object X or the like that is in contact with the probe 33 can be measured as the amount of movement of the spindle 32 from the flat surface of the measurement table 21 to that portion.

The measurement device 20 of the first embodiment includes a measurement table 21, a support 23, and a bracket 25 that constitute a stand that supports the measurement unit 30, as well as a Peltier unit 27 and a fan unit 29. As described above, the support 23 is made of metal, and therefore expands and contracts in the radial and axial directions due to temperature changes. That is, when the ambient temperature of the measurement device 20 changes, the support 23 that supports the measurement unit 30 expands and contracts, and the axial length of the support 23 may become longer or shorter. The axial direction of the support 23 may coincide with the direction of movement of the spindle 32 of the measurement unit 30 supported by it, and thus such a change in the axial length of the support 23 may affect the amount of movement of the spindle 32.

For example, if the axial length of the support 23 increases due to thermal expansion, the measurement unit 30 supported by the support 23 moves in a direction away from the measurement table 21, and the amount of movement of the spindle 32 may increase by approximately the amount of thermal expansion of the support 23. Conversely, if the axial length of the support 23 decreases due to thermal contraction, the measurement unit 30 moves in a direction toward the measurement table 21, and the amount of movement of the spindle 32 may decrease by approximately the amount of thermal contraction of the support 23.

For this reason, in this first embodiment, the support 23 is provided with a Peltier unit 27 or the like capable of controlling the temperature of the support 23, and the constant temperature measurement system 10 is configured so that the cooling and heating by the Peltier unit 27 can be controlled by a temperature controller 70 as described below. This makes it possible to reduce the effect that the change in axial length of the support 23 caused by thermal expansion or thermal contraction has on the amount of movement of the spindle 32 of the measurement unit 30. The configuration of the Peltier unit 27 or the like provided on the support 23 will be described later.

In this way, the constant temperature measurement system 10 of the first embodiment is configured so that, rather than cooling or heating the entire measuring device 20 using the Peltier unit 27 or the like, only a specific part (the support 23 in this example) that may thermally expand or contract due to changes in the ambient temperature of the measuring device 20 and affect the measurement by the measuring device 20 (measurement unit 30) can be locally cooled or heated using the Peltier unit 27 or the like. This makes it possible to efficiently cool or heat the support 23, which is a part that is easily affected by changes in the ambient temperature.

In the first embodiment, an example will be described below in which a dial gauge is used as the measurement unit 30 in an inspection process for measuring the dimensional error of the workpiece W relative to the master workpiece M and judging whether or not the workpiece passes inspection.

As described above, the measuring unit 30 can also be used to measure the dimensions of a specific portion of the workpiece W or the master workpiece M. In addition, if the measuring unit 30 is a dial gauge, it is possible to use a lever type dial gauge in addition to the dial type.

The cooling devices 40, 50 are cooling units capable of cooling or heating the workpiece W to be measured or the master workpiece M (hereinafter, these may be collectively referred to as "workpieces W, M"), and are configured in almost the same way. Therefore, here, the configuration of the cooling devices 40, 50 will be described with reference to Figs. 1 and 2, representing the cooling device 40. The cooling device 50 can be described by replacing the reference numerals "4x" given to each part with "5x" (x is a single digit number). Note that Fig. 2 shows the state before and after placing the workpiece W to be measured (or the master workpiece M) on the cooling device 40 (or the cooling device 50) (Fig. 2(A) shows the state before placing, and Fig. 2(B) shows the state after placing).

The cold/hot device 40 is composed of, for example, a cold/hot cavity 41, a Peltier unit 43, a heat sink 44, a fan unit 47, etc. The cold/hot cavity 41 is, for example, a thick plate made of a relatively inexpensive metal with high thermal conductivity (for example, copper or aluminum), and a recess 42 capable of accommodating the radial half of the workpieces W and M is formed on its upper surface 41a. The shape of this recess 42 varies depending on the shape of the workpieces W and M, but is basically a recessed shape that allows the workpieces W and M to be easily placed in and removed from the cold/hot cavity 41, and is configured so that the contact area between the inner surface of the recess 42 and the outer surface of the master workpiece M can be maximized. Although not shown, female screw holes for attaching the heat sink 44 and the fan unit 47 to the cold/hot cavity 41 by screwing in bolts (not shown) are formed, for example, at the four corners of the cold/hot cavity 41.

As shown in FIG. 2B, when the measured workpiece W or the master workpiece M is placed in the heat/cold cavity 41, if a gap (space) occurs between the inner surface of the recess 42 and the outer surface of the workpieces W and M, machine oil MO can enter between them to improve the heat transfer efficiency between the two. During machining of the measured workpiece W, machine oil MO is sprayed on the measured workpiece W for cooling, and after machining, the measured workpiece W can be placed in a cooling tank filled with machine oil MO. Therefore, since the measured workpiece W after machining is mostly covered with a film of machine oil MO, the machine oil MO covering the workpieces W and M in such a film-like form can be interposed between the recess 42 and the workpieces W and M to suppress a decrease in heat transfer efficiency.

The Peltier unit 43 is a thin plate-shaped cooling/heating module that functions as a heat absorber and heat generator for the cooling/heating device 40. For example, it has many Peltier elements. A Peltier element is a semiconductor element that utilizes the Peltier effect, in which heat is transferred from one metal to the other when current is passed through the junction of dissimilar metals. The Peltier unit 43 is configured by electrically connecting many such Peltier elements in series and sandwiching them between two ceramic substrates. When current is passed in the forward direction, the Peltier unit 43 absorbs heat on one side and generates heat on the other side, and when current is passed in the reverse direction, it generates heat on one side and absorbs heat on the other side. In addition, the amount of heat absorbed or generated can be increased or decreased by increasing or decreasing the power (driving power) supplied to the Peltier unit 43.

In this first embodiment, the ceramic substrate on one side of the Peltier unit 43 is formed in a rectangular shape similar to the bottom surface 41b of the cold/hot cavity 41 so that it can be thermally coupled to the bottom surface 41b of the cold/hot cavity 41 over almost the entire surface. In addition, a paste-like silicone grease with high thermal conductivity is interposed between this ceramic substrate and the bottom surface 41b of the cold/hot cavity 41. The ceramic substrate on the other side of the Peltier unit 43 is thermally coupled to the heat sink 44, which will be described next, via the silicone grease.

The Peltier unit 43 is provided with positive and negative electrodes for supplying DC power, and in this first embodiment, is connected to a Peltier driver circuit (not shown) built into the temperature controller 70. The Peltier unit 43 can switch between absorbing heat (cooling) or generating heat (heating) on one side or the other side by switching the polarity of the DC power supplied. When the heat sink 44 is attached to the cold/hot cavity 41 by screwing in the bolts (not shown), the Peltier unit 43 is sandwiched between the cold/hot cavity 41 and the heat sink 44 and fixed between them.

The Peltier unit 27 of the measuring device 20 described above also functions as a heat absorber and a heat generator. Electrically, it is configured in the same way as the Peltier unit 43, but it is divided into multiple strips that are electrically connected in series. For example, one strip has a long and narrow rectangular shape along the axial direction of the support 23 (cylindrical shape), and multiple strips are attached to the support 23 so that the cross-sectional shape is a square, U-shape, or L-shape so that it can surround the periphery of the support 23. The above-mentioned silicone grease is also interposed between the Peltier unit 27 consisting of these strips and the support 23. The mounting structure of the Peltier unit 27 to the support 23 is configured so that it can be mounted, for example, via a dedicated bracket of the fan unit 29 described later.

The amount of heat absorbed or generated by the Peltier units 43, 53, 27 can be increased or decreased by increasing or decreasing the driving power supplied to the Peltier units 43, 53, 27. As a result, by increasing or decreasing the driving power supplied to the Peltier units 43, 53, it becomes possible to control the temperature at which the cooling devices 40, 50 cool or heat the workpieces W, M (the output temperature of the cooling devices 40, 50).

The heat sink 44 is, for example, an aluminum heat sink having a flat surface on one side and multiple fins 45 for heat dissipation on the other side. The flat surface of the heat sink 44 is formed in the same rectangular shape as the other ceramic substrate constituting the Peltier unit 43 described above so that it can be thermally bonded over almost the entire surface to the other ceramic substrate. A paste-like silicone grease with high thermal conductivity is interposed between this ceramic substrate and the flat surface of the heat sink 44. The multiple fins 45 formed on the other side of the heat sink 44 are positioned so that their tips contact the intake side of the fan unit 47.

The heat sink 44 is screwed to the cold/hot cavity 41 via the bolts not shown in the figure described above, or when the fan unit 47 described next is screwed to the cold/hot cavity 41 via the bolts not shown in the figure described above, the heat sink 44 is sandwiched together with the Peltier unit 43 between the cold/hot cavity 41 and the fan unit 47 and fixed between the Peltier unit 43 and the fan unit 47.

The fan unit 47 is, for example, an axial type cooling fan that can rotate fan blades with a DC motor (the DC motor and fan blades are not shown), and has a function of discharging heat to the outside. In this first embodiment, the fan unit 47 is screwed to the cold cavity 41 or the heat sink 44 via bolts (not shown) so that the intake side is in contact with the other side (fin 45 side) of the heat sink 44 described above, that is, so that the exhaust side faces the surrounding space. This fan unit 47 is supplied with driving power individually from a fan driver circuit (not shown) built into the temperature controller 70 together with the other fan units 29 and 57. Note that a water jacket having a function of discharging heat by circulating cold water may be used instead of the fan unit 47 or in combination with the fan unit 47.

The fan unit 29 of the measuring device 20 described above is electrically configured in the same way as the fan unit 47, but differs from the fan units 47 and 57 in that the size and shape of the fan unit 29 and its fan blades are configured to be suitable for the Peltier unit 27, which is made of a rectangular piece. The mounting structure of the fan unit 29 to the support 23 is configured so that it can be mounted via a dedicated bracket or the like. As with the fan unit 47, the water jacket described above may be used in place of the fan unit 29 or in combination with the fan unit 29.

The temperature sensors 61, 62 are non-contact type radiation temperature sensors that detect infrared rays emitted by the objects to be measured, such as the workpiece W and the master workpiece M, from above the workpieces W, M, respectively, and measure their temperatures. For this reason, the temperature sensors 61, 62 are mounted, for example, on a stand (not shown) so as to maintain a positional relationship that allows them to absorb the infrared rays radiated from the workpieces W, M placed on the cooling devices 40, 50 from diagonally above them.

In this first embodiment, the temperature sensor 61 outputs workpiece temperature information as the temperature information of the measured workpiece W, and the temperature sensor 62 outputs master temperature information as the temperature information of the master workpiece M. Since the temperature sensors 61 and 62 are both connected to the temperature controller 70, the temperature information (workpiece temperature information, master temperature information) output from these sensors is input to the temperature controller 70.

The temperature sensor 63 is a contact type temperature sensor (e.g., a thermocouple or a thermistor) that is attached to the support 23 of the measuring device 20 to measure the temperature of the support 23. The temperature sensor 63 is attached to the support 23, for example, so that its temperature detection portion is in direct contact with the support 23 or indirectly via silicone grease or the like. In this first embodiment, like the temperature sensors 61 and 62, the temperature sensor 63 is also connected to the temperature controller 70. Therefore, the measuring device temperature information output from the temperature sensor 63 as the temperature information of the support 23 of the measuring device 20 is input to the temperature controller 70. Specific temperature information may also be input from outside.

The temperature controller 70 is a microcomputer unit (TCNT) that is composed of, for example, an MPU, memory (RAM, ROM (including EEPROM)), an input/output interface, a Peltier driver circuit, a fan driver circuit, and the like. In this first embodiment, the Peltier unit 43 of the cooling device 40, the Peltier unit 53 of the cooling device 50, and the Peltier unit 27 of the measuring device 20 are connected to the Peltier driver circuit, and the fan units 47, 57, and 29 of the cooling device 40, etc. are connected to the fan driver circuit and are driven and controlled, respectively. Temperature sensors 61 to 63 are connected to the input/output interface of the temperature controller 70, and the workpiece temperature information of the measured workpiece W, the master temperature information of the master workpiece M, and the measuring device temperature information of the support 23 of the measuring device 20 output from these are input to the temperature controller 70.

Based on this temperature information, the temperature controller 70 executes the constant temperature control process and the cold/hot control process described below, thereby controlling the temperature of the Peltier units 43, 53, and 27 of the cold/hot device 40, etc. Note that the fan unit 47 of the cold/hot device 40, the fan unit 57 of the cold/hot device 50, and the fan unit 29 of the measuring device 20 are all controlled to start almost immediately after the power switch (not shown) of the temperature controller 70 is turned on to turn on the power, and to stop after a predetermined time has elapsed upon detection that the power is off. The control of these fan units 47, 57, and 29 may also be configured to start and stop individually based on the work temperature information, master temperature information, and measuring device temperature information input to the temperature controller 70.

In the first embodiment, as shown in FIG. 2, the cold cavity 41, 51 of the cold device 40, 50 is configured with a thick plate, but for example, as shown in FIG. 3(A) and FIG. 3(B), the cold cavity 141 may be configured in the shape of a rectangular box without a lid, in which the internal space SP can be filled with machine oil MO. In the cold device 140 equipped with such a cold cavity 141, the workpiece W, M is accommodated in the internal space SP of the cold cavity 141 and is entirely immersed in the machine oil MO. Therefore, since the entire workpiece W, M is cooled or heated together with the machine oil MO, it is possible to control the temperature of the workpiece W, M more efficiently than the cold cavity 41, 51 of the cold device 40, 50 in FIG. 2. For convenience of drawing representation, the machine oil MO stored in the internal space SP is colored light gray in FIG. 3.

The cold/heat device 140 is composed of, for example, a cold/heat cavity 141, a Peltier unit 145, a heat sink 146, fan units 148, 149, etc. The cold/heat cavity 141 is composed of, for example, four side walls 142 arranged in a square shape, made of a relatively inexpensive metal with high thermal conductivity (e.g., copper or aluminum), and a bottom 143 that closes the bottom of the internal space SP surrounded by these side walls 142. All of these are thick and formed as one piece. The bottom 143 has multiple female threaded holes for mounting by screwing in bolts (not shown). Compared to the cold/heat cavities 41, 51 of the cold/heat devices 40, 50, the opening and bottom 143 of the cold/heat cavity 141 are formed as an elongated rectangle that is slightly larger than the axial shape of the workpieces W, M.

The Peltier unit 145 is configured in substantially the same manner as the Peltier unit 43 described above, except that the ceramic substrate of the Peltier unit 145 is formed in the same elongated rectangular shape as the bottom 143 of the cold/hot cavity 141 so that it can be thermally coupled over substantially the entire surface of the bottom 143. The heat sink 146 having a plurality of fins 147 is also configured in substantially the same manner as the heat sink 44 described above, except that it is formed in the same elongated rectangular shape as the bottom 143.

The heat sink 146 is screwed to the bottom 143 of the cold cavity 141 via the bolts not shown in the figure described above, or when the fan units 148, 149 are screwed to the bottom 143 via the bolts not shown in the figure described above, the heat sink 146 is sandwiched together with the Peltier unit 145 between the bottom 143 of the cold cavity 141 and the fan units 148, 149, and is fixed between the Peltier unit 145 and the fan units 148, 149.

Since the heat sink 146 is formed in an elongated rectangular shape, the cooling device 140 is equipped with two small fan units 148, 149. The fan units 148, 149 are configured similarly to the fan units 47, 57, except that they are smaller than the fan units 47, 57. The fan units 148, 149 are both screwed to the cooling cavity 141 or the heat sink 146 via bolts (not shown). As with the fan unit 47, the water jacket described above may be used in place of the fan units 148, 149 or in combination with the fan units 148, 149.

The amount of machine oil MO stored in the internal space SP may be an amount that allows the entire workpieces W, M to be immersed in the machine oil MO, or an amount that allows part of the workpieces W, M to be exposed to the internal space SP (dotted line L shown in Figure 3(B)). By keeping the amount of machine oil MO injected near the dotted line L, part of the workpieces W, M are exposed to the internal space SP, so that the temperature is less affected by the machine oil MO when measuring the temperature with the temperature sensors 61, 62 than when the entire workpieces W, M are covered in the machine oil MO. This makes it possible to improve the accuracy of temperature measurement by the temperature sensors 61, 62 (radiation temperature sensors).

Next, the constant temperature control process and cold/hot control process executed by the temperature controller 70 will be described with reference to Figures 4 and 5. The constant temperature control process and cold/hot control process are realized by the MPU of the temperature controller 70 executing a constant temperature control program and a cold/hot control program stored in the memory (ROM) of the temperature controller 70. In this first embodiment, the constant temperature control process and the cold/hot control process are executed in parallel as described below. For this reason, a task control program is also implemented in the temperature controller 70. The constant temperature control program (constant temperature control process) is started immediately after the power switch (not shown) of the temperature controller 70 is turned on to power up (constant temperature control task).

Note that, although the description here is based on the assumption that the workpiece W to be measured is placed on the cooling device 40 and the master workpiece M is placed on the cooling device 50, the same description can be given for the case where, for example, the workpiece W to be measured and the master workpiece M are not placed on either the cooling device 40, 50. When the workpiece W to be measured and the master workpiece M are not placed on either the cooling device 40, 50, the temperature measured by the temperature sensors 61, 62 is the temperature of the cooling cavities 41, 51, so in the following description of the constant temperature control process and the cooling control process, the temperature of the workpiece W to be measured and the master workpiece M (master temperature information and workpiece temperature information) is the temperature of the cooling cavities 41, 51. In this case, the cooling cavities 41, 51 are in a standby state in preparation for the placement of the workpieces W and M.

As shown in FIG. 4, the constant temperature control process first performs a predetermined initialization process in step S101. In this process, for example, the work area and flags for this process in the memory (RAM) of the temperature controller 70 are cleared, and control commands for initial setting are sent to the Peltier driver circuit and the temperature sensors 61 and 62.

In the next step S103, a specific temperature information acquisition process is performed. The main purpose of this constant temperature control process is to control the Peltier units 43, 53 of the cooling devices 40, 50 and the Peltier unit 27 of the measuring device 20 to keep the temperatures of the measured work W, the master work M, and the support 23 of the measuring device 20 at a specific, identical temperature (specific temperature). Therefore, in this specific temperature information acquisition process, information on the specific temperature to be matched is acquired.

The specific temperature information is obtained, for example, by (1) inputting a numerical value from outside the temperature controller 70 via an operation panel (not shown). The input operation is performed by a person in charge of the inspection process, and is set to, for example, 23°C (predetermined temperature) (if an error of 1°C above or below is allowed, such as 23°C ±1°C, the upper and lower limits are set to 22°C to 24°C). In addition, (2) the temperature information (workpiece temperature information) of the current measured workpiece W measured by the temperature sensor 61 and input to the temperature controller 70 may be obtained as the specific temperature information. Furthermore, (3) the temperature information (measuring device temperature information) of the current support 23 of the measuring device 20 measured by the temperature sensor 63 and input to the temperature controller 70 may be obtained as the specific temperature information. In addition, (4) the temperature information (master temperature information) of the current master workpiece M measured by the temperature sensor 62 and input to the temperature controller 70 may be obtained as the specific temperature information.

That is, in the above case (1), the numerical information input to the temperature controller 70 from an operation panel (not shown) or the like is acquired as the specific temperature information, and in the above cases (2) to (4), the work temperature information (output by temperature sensor 61), the measuring device temperature information (output by temperature sensor 63), and the master temperature information (output by temperature sensor 62) input to the temperature controller 70 from the temperature sensors 61 to 63 are acquired as the specific temperature information. Note that if the previous specific temperature information is stored in the memory of the temperature controller 70 by the setting information storage process (S117) described later, the previous specific temperature information may be read from the memory and acquired as the current specific temperature information. The specific temperature information acquired by the specific temperature information acquisition process (S103) is stored in the memory (RAM) of the temperature controller 70 by the specific temperature information storage process in step S105.

In the next step S107, a cold/heat control start process is performed. In this process, the cold/heat control program stored in the memory (ROM) of the temperature controller 70 is started by the MPU, and the cold/heat control process shown in FIG. 5 is started. In this first embodiment, separate cold/heat control processes (cold/heat control tasks) are executed corresponding to the Peltier units 43, 53 of the cold/heat devices 40, 50 and the Peltier unit 27 of the measuring device 20. Therefore, in this first embodiment, the constant temperature control task (parent task) by the constant temperature control process (FIG. 4) and the three cold/heat control tasks (child tasks) by the cold/heat control process (FIG. 5) are executed in parallel. Strictly speaking, as described later, the Peltier drive control task is also executed as a child task (grandchild task) in the cold/heat control process (FIG. 5). Such multitasking process is performed by a task control program implemented in the temperature controller 70. The cold/heat control process in FIG. 5 will be described later.

After step S107 starts each cooling/heating control process (FIG. 5) for the Peltier units 43, 53, and 27, if the temperature measured by the temperature sensors 61-63 matches the target temperature (S307 in FIG. 5; Yes), as described below, temperature matching information is output to this constant temperature control process (S311 in FIG. 5).

For example, the cooling/heating control process (FIG. 5) that controls the Peltier unit 43 of the cooling/heating device 40 outputs work temperature coincidence information to this constant temperature control process, indicating that the temperature of the workpiece W to be measured coincides with a specific temperature. The cooling/heating control process (FIG. 5) that controls the Peltier unit 53 of the cooling/heating device 50 outputs master temperature coincidence information to this constant temperature control process, indicating that the temperature of the master workpiece M coincides with a specific temperature. Furthermore, the cooling/heating control process (FIG. 5) that controls the Peltier unit 27 of the measuring device 20 outputs measuring device temperature coincidence information to this constant temperature control process, indicating that the temperature of the support 23 coincides with a specific temperature.

Therefore, in this constant temperature control process, the temperature coincidence information acquisition process in step S109 acquires each piece of temperature coincidence information (workpiece temperature coincidence information, master temperature coincidence information, measuring device temperature coincidence information), and the next step S111 performs a constant temperature judgment process to determine whether or not these three pieces of temperature coincidence information are complete, that is, whether or not the temperatures of the measured workpiece W, the master workpiece M, and the support 23 of the measuring device 20 are all uniformly (matching) and maintained at a specific temperature. If it is determined that the temperatures are all uniformly maintained at a specific temperature (constant temperature completion) (S111; Yes), the constant temperature completion information output process is performed in the following step S113. On the other hand, if it is determined that the temperatures have not yet been uniformly (constant temperature incomplete) (S111; No), the constant temperature incomplete information output process is performed in step S114.

The constant temperature completion information and constant temperature incompletion information output by steps S113 and S114 are output to the outside as digital or analog signals from the input/output interface of the temperature controller 70, for example. Therefore, for example, a two-color red and green indicator light can be configured to light up green when a signal for constant temperature completion information is output, and light up red when a signal for constant temperature incompletion information is output, so that the person in charge of the inspection process can be notified of the constant temperature completion or incompletion information by the light emission color. Note that instead of an external output, a display device such as a color LED can be provided in the temperature controller 70 to emit green or red light.

In step S115, a process is performed to determine whether or not the power switch (not shown) of the temperature controller 70 has been turned off. For example, if an input of an interrupt signal triggered by turning the power switch off is detected (S115; Yes), the setting information storage process is performed in the following step S117. If such an input of an interrupt signal is not detected (S115; No), the power switch has not been turned off, so the process returns to step S109 and the temperature consistency information acquisition process is performed again.

In the setting information storage process of step S117, for example, the information on the specific temperature (the specific same temperature at which the temperatures of the measured workpiece W, the master workpiece M, and the support 23 of the measuring device 20 should be uniform) acquired in S103 and stored in the memory in step S105 is stored in the memory (EEPROM) of the temperature controller 70 as the previous specific temperature. This makes it possible to read out the previous specific temperature from the memory, for example, in the specific temperature information acquisition process (S103).

Then, the next step S119 performs a cold/heat control end process, and control end information is output to the cold/heat control process (Figure 5). More specifically, control end information is sent from the constant temperature control task to the cold/heat control task via inter-task communication. In this first embodiment, separate cold/heat control processes (cold/heat control tasks) are executed corresponding to the Peltier units 43, 53 of the cold/heat devices 40, 50 and the Peltier unit 27 of the measurement device 20. Therefore, by sending this control end information, a "Yes" determination is made in the control end determination process (S315) performed in each cold/heat control process (Figure 5), and the execution of each cold/heat control process (cold/heat control task) is ended. Thereafter, this constant temperature control process also ends.

Next, the cold/heat control process shown in FIG. 5 will be described. As described above, this cold/heat control process is started by starting up the cold/heat control program by the cold/heat control start-up process (S107) of the constant temperature control process in FIG. 4. In this first embodiment, three cold/heat control processes corresponding to the Peltier units 43, 53 of the cold/heat devices 40, 50 and the Peltier unit 27 of the measuring device 20 are executed individually. Since the cold/heat control processes for these Peltier units 43, 53, 27 are almost the same, the cold/heat control process corresponding to the Peltier unit 43 of the cold/heat device 40 will be described here as a representative.

As shown in FIG. 5, in the cold/hot control process, first, a target temperature setting process is performed in step S301. The target temperature is the temperature of the measured workpiece W that is cooled or heated by the cold/hot device 40, and is the temperature that is aimed to be reached. In this first embodiment, this target temperature is a specific temperature stored in memory by the setting information storage process (S117) of the constant temperature control process (FIG. 4), so in this step S301, the information on the specific temperature read from the memory is set as the target temperature.

In the next step S303, a Peltier control start process is performed. In this process, Peltier drive control is started to supply drive power to the Peltier unit 43 of the cooling/heating device 40. In this Peltier drive control, for example, PID-controlled drive power (voltage, current) based on the workpiece temperature information of the measured workpiece W output from the temperature sensor 61 is supplied to the Peltier unit 43 by PWM control. The Peltier drive control is executed as a Peltier drive control task by the Peltier drive control program. This starts the supply of drive power to the Peltier unit 43, and the Peltier unit 43 starts absorbing or generating heat, starting the cooling or heating of the measured workpiece W placed in the cooling/heating cavity 41.

In the case of the cooling device 50, the driving power PID-controlled based on the master temperature information of the master workpiece M output from the temperature sensor 62 is supplied to the Peltier unit 53 by PWM control. In the case of the measuring device 20, the driving power PID-controlled based on the measuring device temperature information of the support 23 output from the temperature sensor 63 is supplied to the Peltier unit 27 by PWM control. These are executed as Peltier driving controls (Peltier driving control tasks) separate from the Peltier driving control of the Peltier unit 43.

In the next step S305, a temperature information acquisition process is performed. In the cooling device 40, this temperature information is the current temperature of the workpiece W to be measured. Therefore, in this process, the current workpiece temperature information of the workpiece W to be measured output from the temperature sensor 61 is acquired. Note that the temperature information in step S305 is the current master temperature information of the master workpiece M output from the temperature sensor 62 in the cooling device 50, and is the current measuring device temperature information of the support 23 output from the temperature sensor 63 in the measuring device 20.

In the following step S307, the current workpiece temperature information acquired in step S305 is compared with the target temperature information set in step S301 to determine whether the current temperature of the measured workpiece W matches the target temperature. In other words, it is determined whether the temperature of the measured workpiece W has reached the target temperature (specific temperature). This match includes cases where the temperature matches the target temperature perfectly, as well as cases where the temperature matches within a pre-accepted error range (e.g., ±1°C).

If it is determined that the temperature of the workpiece W to be measured matches the target temperature (S307; Yes), the workpiece W to be measured has reached a specific temperature and no further cooling or heating is required, so the Peltier drive control is terminated by the Peltier control termination process in the next step S309. This ends the supply of drive power to the Peltier unit 43, so the heat absorption or generation of the Peltier unit 43 ends and the cooling or heating of the workpiece W to be measured placed in the cold/heat cavity 41 stops. On the other hand, if it is determined that the temperature of the workpiece W to be measured does not match the target temperature (S307; No), it is necessary to continue cooling or heating the workpiece W to be measured, so the process returns to step S305 and the temperature information acquisition process is performed again.

In the temperature agreement information output process of step S311, work temperature agreement information indicating that the temperature of the measured workpiece W matches the target temperature, i.e., the specific temperature, is output to the constant temperature control process (Figure 4). More specifically, the work temperature agreement information is sent from the thermal control task to the constant temperature control task via inter-task communication. This makes it possible to acquire the work temperature agreement information in the temperature agreement information acquisition process (S109) of the constant temperature control process (Figure 4) as described above. In this way, the temperature agreement information output to the constant temperature control process of Figure 4 is master temperature agreement information in the case of the thermal control process that controls the Peltier unit 53 of the thermal device 50, and is measuring device temperature agreement information in the case of the thermal control process that controls the Peltier unit 27 of the measuring device 20, and is acquired by the temperature agreement information acquisition process (S109).

In the next step S313, a control information acquisition process is performed. This process acquires control information such as control end information sent from the cold/hot control end process (S119) of the constant temperature control process (FIG. 4) described above to this cold/hot control process. This control end information is sent from the constant temperature control task to the cold/hot control task when the power switch of the temperature controller 70 is turned off. Therefore, in the control end determination process in the following step S315, if the sent control information is control end information (S315; Yes), this cold/hot control process is terminated. Also, if the sent control information is not control end information (S315; No), the power switch of the temperature controller 70 is still on, and the cold/hot control of the Peltier unit 43 is continuing. Therefore, the Peltier control start process and the like are performed again from step S303.

By performing this cold/hot control process in this manner, the Peltier units 43, 53, 27 cool or heat the cold devices 40, 50 and the measuring device 20, making it possible for the workpieces W, M and the support 23 of the measuring device 20 to be kept at a specific temperature. In addition, when the temperatures of the measured workpiece W, the master workpiece M and the support 23 match the specific temperature, the cold/hot control processes (cold/hot control tasks) that control the Peltier units 43, 53, 27 output workpiece temperature agreement information, master temperature agreement information and measuring device temperature agreement information to the constant temperature control process (constant temperature control task). Therefore, in the above-mentioned constant temperature control process (Figure 4), it becomes possible to perform a constant temperature determination process (S111) to determine whether the temperatures of the workpieces W, M and the support 23 of the measuring device 20 are all kept at the specific temperature.

When the constant temperature determination process (S111) outputs constant temperature completion information, the temperatures of the works W and M placed on the cooling and heating devices 40 and 50 have reached a specific temperature, and the person in charge of the inspection process who recognizes the completion of constant temperature from the color of the two-color indicator light, for example, removes the master work M at the specific temperature from the cooling and heating device 50 and sets it on the measurement table 21 of the measuring device 20. At this time, the support 23 of the measuring device 20 that supports the measuring unit 30 is also kept at the same specific temperature as the master work M. As a result, the measuring unit 30 is supported at a fixed position, and the movement amount Mm of the spindle 32 displayed on the display unit 35 when the person in charge operates the measuring unit 30 and, for example, brings the measuring probe 33 into contact with the measuring point of the master work M, becomes a fixed reference value at the specific temperature.

The person in charge then takes out the workpiece W to be measured at a specific temperature from the cooling device 40 and sets it on the measuring table 21 of the measuring device 20, and operates the measuring unit 30 to bring the measuring probe 33 into contact with the measuring point of the workpiece W to be measured. As a result, the movement amount Mw of the spindle 32 for the workpiece W to be measured is displayed on the display unit 35. Therefore, the dimensional error of the workpiece W to be measured relative to the master workpiece M is calculated as the difference Md (= Mw - Mm) between the movement amount Mm of the reference value and this movement amount Mw. For example, if the measuring unit 30 is a dial gauge, the pass/fail judgment of the workpiece W to be measured can be made depending on whether the pointer 35a indicating the movement amount Mw is within the range of the limit needles that clearly indicate the upper and lower limits of the allowable error range.

When the workpiece W to be measured is placed on the cooling device 40 during the inspection process, or when the next new workpiece W to be measured is placed on the cooling device 40, the person in charge of the inspection process waits until the temperatures of the workpieces W, M and the support 23 of the measuring device 20 reach a specific temperature, and then removes the workpiece W to be measured from the cooling device 40 and sets it on the measuring table 21 of the measuring device 20. Then, the measurement unit 30 is operated to measure the error of the workpiece W to be measured. The measurement of the movement amount of the master workpiece M, which is the reference value, does not need to be performed every time the error of a new workpiece W to be measured is measured, but is performed every predetermined time (e.g., every 6 hours or every 12 hours) or every number of measurements of the workpiece W to be measured (e.g., every 500 or 1000 pieces).

As described above, the constant temperature measurement system 10 according to the first embodiment includes the measurement device 20 having the measurement unit 30 and the Peltier unit 27 on the support 23, the cooling and heating devices 40, 50 having the cold and heating cavities 41, 51 cooled and heated by the Peltier units 43, 53, the temperature sensors 61 to 63, and the temperature controller 70. The temperature sensor 61 measures the temperature of the workpiece W to be measured and outputs workpiece temperature information. The temperature sensor 62 measures the temperature of the master workpiece M and outputs master temperature information. The temperature sensor 63 measures the temperature of the support 23 of the measurement device 20 and outputs measurement device temperature information. The temperature controller 70 controls the output temperature of the Peltier units 43, 53 of the cooling and heating devices 40, 50 and the Peltier unit 27 of the measurement device 20 so that the temperatures of the works W, M and the support 23 of the measurement device 20 match a predetermined temperature (e.g., 23°C) (S301 to S309, S313, S315).

As a result, even if the temperatures of the master workpiece M and the measured workpiece W are different, the master workpiece M and the support 23 of the measuring device 20 are different, or the temperatures of the measured workpiece W and the support 23 of the measuring device 20 are different, the workpieces W, M and the support 23 are cooled or heated (S301 to S309, S313, S315) and these temperatures become the same as a predetermined temperature (for example, 23°C) (S111; Yes). In addition, since each temperature sensor 61 to 63 directly measures the temperature of the workpieces W, M and the support 23 of the measuring device 20, it is possible to measure with higher accuracy than when the temperature of the workpieces W, M and the support 23 are indirectly measured by measuring the temperature of the cooling and heating devices 40, 50, etc. Furthermore, since the cooling and heating cavities 41, 51 of the cooling and heating devices 40, 50 are constructed using metals with high thermal conductivity (e.g., copper, aluminum, etc.), it is possible to cool or heat the workpieces W, M in a short time compared to using a stone surface plate (stone slab) or the like, which has a lower thermal conductivity than these metals. This makes it possible to match (align) the temperatures of these three with high precision and in a short time. Therefore, it is possible to measure the shape and dimensions of the workpieces W, M, whose temperatures are precisely controlled so that they are not easily affected by thermal expansion or contraction, without installing any large-scale equipment.

In the above-described first embodiment, a configuration in which a Peltier unit 27 is provided on the support 23 of the measuring device 20 as a second cooling/heating unit that cools or heats the measuring device has been described as an example, but if the temperatures of the measured workpiece and the master workpiece are to be adjusted to the temperature of the measuring device, a configuration in which the Peltier unit 27 (second cooling/heating unit) is omitted may be adopted.

That is, the constant temperature measurement system includes the measurement device 20 equipped with the measurement unit 30, the cooling and heating devices 40, 50 having the cooling and heating cavities 41, 51 cooled and heated by the Peltier units 43, 53, the temperature sensors 61 to 63, and the temperature controller 70, excluding the Peltier unit 27 of the measurement device 20. In this case, the temperature sensor 61 measures the temperature of the workpiece W to be measured and outputs workpiece temperature information. The temperature sensor 62 measures the temperature of the master workpiece M and outputs master temperature information. The temperature sensor 63 measures the temperature of the support 23 of the measurement device 20 and outputs measurement device temperature information. The temperature controller 70 controls the output temperature of the cooling device 50 so that the temperature of the master workpiece M coincides with the temperature of the support 23 of the measurement device 20 (S301 to S309, S313, S315), and controls the output temperature of the cooling device 40 so that the temperature of the workpiece W to be measured coincides with the temperature of the support 23 of the measurement device 20 (S301 to S309, S313, S315).

As a result, even if the temperatures of the master workpiece M and the measured workpiece W are different, the master workpiece M and the support 23 of the measuring device 20 are different, or the temperatures of the measured workpiece W and the support 23 of the measuring device 20 are different, the workpieces W and M are cooled or heated (S301 to S309, S313, S315), and the temperature of the workpieces W and M becomes the same as the temperature of the support 23 of the measuring device 20 (S111; Yes). In addition, since each temperature sensor 61 to 63 directly measures the temperature of the workpieces W and M and the support 23 of the measuring device 20, it is possible to measure the temperature of the workpieces W and M with higher accuracy than when the temperature of the cooling and heating devices 40 and 50 is measured and the temperature of the workpieces W and M is indirectly measured. Furthermore, since the cooling and heating cavities 41 and 51 of the cooling and heating devices 40 and 50 are made of metals with high thermal conductivity (e.g., copper, aluminum, etc.), it is possible to cool and heat the workpieces W and M in a short time compared to a stone surface plate (stone slab) with a lower thermal conductivity than these metals. Therefore, it is possible to match (align) the temperatures of these three with high precision and in a short time without providing a Peltier unit 27 in the measuring device 20. Therefore, it is possible to measure the shape and dimensions of the workpieces W and M, whose temperatures are precisely controlled so that they are not easily affected by thermal expansion or contraction, without providing any large-scale equipment.

In addition, in the first embodiment described above, a configuration in which a cooling device 40 is provided as the second cooling/heating unit (claim 2) or the third cooling/heating unit (claim 3) that cools or heats the workpiece to be measured has been exemplified, but when matching the temperatures of the master workpiece and the measuring device to those of the workpiece to be measured, a configuration in which the cooling device 40 (second cooling/heating unit (claim 2), third cooling/heating unit (claim 3)) is omitted may be adopted.

That is, the constant temperature measurement system includes the measurement device 20 equipped with the measurement unit 30 and having the Peltier unit 27 on the support 23, the cooling device 50 having the cold cavity 51 cooled or heated by the Peltier unit 53, the temperature sensors 61 to 63, and the temperature controller 70, excluding the cooling device 40. In this case, the temperature sensor 61 measures the temperature of the workpiece W to be measured and outputs workpiece temperature information. The temperature sensor 62 measures the temperature of the master workpiece M and outputs master temperature information. The temperature sensor 63 measures the temperature of the support 23 of the measurement device 20 and outputs measurement device temperature information. The temperature controller 70 controls the output temperature of the cooling device 50 so that the temperature of the master workpiece M matches the temperature of the workpiece W to be measured (S301 to S309, S313, S315), and controls the output temperature of the Peltier unit 27 of the measurement device 20 so that the temperature of the support 23 of the measurement device 20 matches the temperature of the workpiece W to be measured (S301 to S309, S313, S315).

As a result, even if the temperatures of the master work M and the measured work W are different, the master work M and the support 23 of the measuring device 20 are different, or the measured work W and the support 23 of the measuring device 20 are different, the master work M and the support 23 of the measuring device 20 are cooled or heated (S301 to S309, S313, S315), and the temperature of the master work M and the support 23 of the measuring device 20 becomes the same as the temperature of the measured work W (S111; Yes). In addition, since each temperature sensor 61 to 63 directly measures the temperature of the work W, M and the support 23 of the measuring device 20, it is possible to measure with higher accuracy than when the temperature of the work W, M is indirectly measured by measuring the temperature of the cooling and heating devices 40, 50, etc. Furthermore, because the cooling/heating cavity 51 of the cooling/heating device 50 is constructed using a metal with high thermal conductivity (e.g., copper, aluminum, etc.), it is possible to cool or heat the master work M in a short time compared to a stone surface plate (stone slab) that has a lower thermal conductivity than these metals. Therefore, it is possible to align the temperatures of these three with high precision and in a short time without installing a cooling/heating device 40. Therefore, it is possible to measure the shape and dimensions of the workpieces W and M, whose temperatures are precisely controlled so that they are not easily affected by thermal expansion or thermal contraction, without installing any large-scale equipment.

In addition, in the above-mentioned first embodiment, the measured workpiece W and the master workpiece M are metal shaft parts of the same material, but the measured workpiece W and the master workpiece M may be made of different materials. In such a case, for example, when there is a difference in thermal expansion or thermal contraction between the measured workpiece W and the master workpiece M due to the difference in material, an algorithm may be configured to determine in advance the temperature difference ΔTa at which the geometric dimensions of both are the same, and to set the target temperature (specific temperature) including such temperature difference ΔTa. This makes it possible to absorb dimensional errors due to differences in the materials of the measured workpiece W and the master workpiece M, thereby improving the accuracy of the judgment made in step S307.

[Second embodiment]
Next, a second embodiment of the constant temperature measurement system of the present invention will be described with reference to Figures 6 and 7. The constant temperature measurement system 10' of this second embodiment differs from the constant temperature measurement system 10 of the first embodiment mainly in the following four points, and is otherwise configured in substantially the same manner as the constant temperature measurement system 10. Therefore, in this second embodiment, components that are substantially the same as those in the constant temperature measurement system 10 are denoted by the same reference numerals and descriptions thereof will be omitted.

A measuring unit 30' is provided instead of the measuring unit 30. A measurement controller 80 is provided in addition to the temperature controller 70. A display 90 is provided instead of an indicator light that indicates completion or incompletion of constant temperature. A measurement preparation completion button 100 is provided.

The measurement unit 30' provided in the measurement device 20' is, for example, a linear gauge, and has a main body 31' that can start measurement when a measurement start command is input from the outside, convert the movement amount of the spindle 32 into an electrical signal, and output it to the outside. In the second embodiment, for example, in the measurement unit 30', the movement amount of the spindle 32 represents the respective dimensional values Sm and Sw at the measurement points of the master work M and the measured work W. Therefore, when a measurement start command is output from the measurement controller 80, an electrical signal representing the movement amount is input to the measurement controller 80 as dimensional information. In addition to the dimensional information output from the main body 31', the measurement controller 80 also receives constant temperature completion information and constant temperature incompletion information output from the temperature controller 70. In addition, a display 90 (a type with a speaker with a built-in audio amplifier) is also connected to the measurement controller 80. The measurement unit 30' does not have a display unit 35.

The measurement controller 80 is a microcomputer unit (MCNT) that is similar to the temperature controller 70 and is composed of, for example, an MPU, memory (RAM, ROM (including EEPROM)), an input/output interface, a video card, etc. In the second embodiment, the main body 31' of the measurement unit 30' and the temperature controller 70 are connected to the input/output interface, and the dimensional information, constant temperature completion information, and constant temperature incompletion information output from these are input to the measurement controller 80. A display 90 is connected to the video card, and the constant temperature completion information, pass information, fail information, and error information output from the measurement controller 80 as described below are displayed on the display 90.

In the second embodiment, the measurement controller 80 executes the measurement control process described below based on the dimensional information, constant temperature completion information, and constant temperature incompletion information, and thereby pass information and the like are output and displayed on the display 90. From here, the measurement control process executed by the measurement controller 80 will be described with reference to FIG. 7. This measurement control process is realized by the MPU of the measurement controller 80 executing a measurement control program stored in the memory (ROM) of the measurement controller 80. The measurement control program (measurement control process) is started immediately after the power switch (not shown) of the measurement controller 80 is turned on to power up.

As shown in FIG. 7(A), the measurement control process first performs a predetermined initialization process in step S501. In this process, for example, the work area and flags for this process in the memory (RAM) of the measurement controller 80 are cleared, and a control command for initial setting is sent to the video card.

In this measurement control process, before measuring the dimensions of the workpiece W to be measured, the dimensions of the master workpiece M are measured first to obtain master dimension information. Therefore, in the next step S502, master dimension measurement processing is performed. This processing displays on the display 90 that the temperatures of the works W, M and the support 23 of the measuring device 20' are uniformly maintained at a specific temperature based on the constant temperature completion information from the temperature controller 70, that is, that the constant temperature completion state has been reached, and then obtains the dimension information output from the measuring unit 30'. The flow of the dimension measurement processing is illustrated in FIG. 7(B) as a subroutine. Therefore, from here on, the description will be given mainly with reference to FIG. 7(B). Note that the dimension measurement processing in FIG. 7(B) is the same as the workpiece dimension information measurement processing described in step S503, as described later.

As shown in FIG. 7(B), in the dimension measurement process, first, in step S601, constant temperature completion/incompletion information acquisition processing is performed. That is, as described in the first embodiment, in the constant temperature control processing shown in FIG. 4, constant temperature completion information and constant temperature incompletion information indicating whether or not three pieces of temperature consistency information (work temperature consistency information, master temperature consistency information, and measuring device temperature consistency information) have been obtained are output from the temperature controller 70 (S113, S114). Therefore, in this constant temperature completion/incompletion information acquisition processing, the constant temperature completion information and constant temperature incompletion information are acquired.

The constant temperature completion information is output when the three pieces of temperature consistency information are all collected, and indicates that the workpieces W, M and the support 23 of the measuring device 20 are maintained at a specific temperature, i.e., the constant temperature is complete. The constant temperature incomplete information is output when the three pieces of information are not all collected, and indicates that the constant temperature has not yet been completed. Therefore, in the following step S603, the process returns to step S601 (S603; No) until the constant temperature completion information is acquired, and constant temperature completion/incomplete information acquisition processing is performed. Then, when the constant temperature completion information is acquired (S603; Yes), the constant temperature completion information output processing is performed in the next step S605.

In the constant temperature completion information output process in step S605, notification information is output to the display 90 to inform the person in charge of the inspection process that the constant temperature has been completed. For example, the text information "Constant temperature completed!" is displayed large on the display 90 in a conspicuous color or color scheme so that it is visually recognizable, and audio information that evokes the completion of the constant temperature is output from the speaker of the display 90 so that it is audibly recognizable.

As a result, when a person in charge of the inspection process recognizes that the temperature of the workpieces W, M or the support 23 of the measuring device 20 has reached a specific temperature, for example, the master workpiece M at the specific temperature is removed from the cooling device 50 and set on the measuring table 21 of the measuring device 20', and then the person in charge presses the measurement preparation completion button 100, the signal input (preparation completion information) is input to the measurement controller 80.

When this preparation completion information is input, and the judgment process in the next step S607 judges that preparation for measurement by the measuring device 20' (measuring unit 30') is complete (S607; Yes), a measurement start command is output to the measuring unit 30' in the next step S609. As a result, the measured workpiece dimension information of the master workpiece M is output from the measuring unit 30' and input to the measurement controller 80. The master dimension information output from the measuring unit 30' is acquired by the dimension information acquisition process in step S611, and then stored in the memory (RAM) of the measurement controller 80 by the dimension information storage process in the following step S613.

Returning to the measurement control process shown in FIG. 7(A), next, the dimensions of the workpiece W to be measured are measured (S503). In the workpiece dimension measurement process (S503), the dimension measurement process shown in FIG. 7(B) is executed, similar to the master dimension measurement process described above. That is, the workpiece W to be measured is also removed from the cooling and heating device 40 and set on the measurement table 21 of the measuring device 20' in the same manner as the master workpiece M, and then measured by the measuring unit 30', and the workpiece dimension information is stored in the memory of the measurement controller 80 (S607 to S613). When the series of dimension measurement processes is completed in this manner, the process returns to the measurement control process shown in FIG. 7(A).

In the next step S505, OK/NG processing is performed. This processing determines whether the measured workpiece W passes or fails based on the dimensional information acquired by the dimension measurement processing (S503), and the flow of this processing is shown as a subroutine in FIG. 7(C). Therefore, from here on, the explanation will be given mainly with reference to FIG. 7(C).

As shown in FIG. 7(C), in the OK/NG process, first, a dimensional information read process is performed in step S701. As described above, the memory (RAM) of the measurement controller 80 stores the dimensional information (work dimensional information, master dimensional information) of the workpieces W and M measured by the measurement device 20' (measurement unit 30') (S613). Therefore, in this process, this dimensional information is read from the memory of the measurement controller 80.

Then, in step S703, a dimensional error calculation process is carried out to calculate the dimensional error of the measured workpiece W relative to the master workpiece M. For example, the dimensional error Sd (= Sw - Sm) is calculated by subtracting the dimensional value Sm of the master workpiece M based on the master dimensional information from the dimensional value Sw of the measured workpiece W based on the workpiece dimensional information. The next step S705 determines whether the calculated dimensional error Sd is within a predetermined range.

For example, if the dimensional error Sd for passing is previously set to be "within a range of ±0.05 mm," when the pass/fail judgment in step S705 determines that the dimensional error Sd of the measured workpiece W is within that range (S705; pass), the measured workpiece W passes the inspection, and the process moves to pass information output processing in step S707, where pass information that can inform the person in charge of the inspection process that the measured workpiece W has passed the inspection is output to the display 90. For example, processing is performed in which information such as letters or symbols "OK" or "○" is displayed large on the display 90 in a conspicuous color or color scheme so that it is visually recognizable, or sound information that gives the impression of passing the inspection is output from the speaker of the display 90 so that it is audibly recognizable.

On the other hand, when it is determined that the dimensional error Sd of the measured workpiece W is outside the range (S705; Fail), the measured workpiece W has failed the inspection, and so the process proceeds to the failure information output process of step S708, where failure information that can inform the person in charge of the inspection process that the measured workpiece W has failed is output to the display 90. For example, the process may be performed such that information such as letters or symbols "NG" or "x" are displayed large on the display 90 in a conspicuous color or color scheme so that it is visually recognizable, or sound information that gives the impression of failure is output from the speaker of the display 90 so that it is auditorily recognizable.

In the second embodiment, the error information output process is also performed in the subsequent step S709. This process outputs the dimensional error information (dimensional error Sd) calculated in step S703 to the display 90. For example, the dimensional error Sd is processed such that the numerical value is displayed as text information on the display 90 so that it can be visually recognized, or the numerical value is read out in a synthesized voice and output from the speaker of the display 90 so that it can be audibly recognized.

When the numerical value of the dimensional error Sd is displayed as text information on the display 90 in the error information output process (S709), for example, the numerical value of the product that passed the inspection may be displayed in blue text, and the numerical value of the product that failed the inspection may be displayed in red text. This makes it easy to visually distinguish between the numerical values of the product that passed the inspection and the product that failed the inspection based on the difference in text color. In addition, either before or after the error information output process (S709), the numerical information of the dimensional error Sd may be stored sequentially in the memory (RAM or EEPROM) of the measurement controller 80. This makes it possible to utilize each stored and accumulated error information as quality control information for the measured workpiece W.

The algorithm for the OK/NG process may be configured so that only one of the pass information output process (S707, S708) and the error information output process (S709) is performed. When the series of OK/NG processes is completed in this manner, the process returns to the measurement control process shown in FIG. 7(A).

In the next step S507, a process is performed to determine whether or not the power switch (not shown) of the measurement controller 80 has been turned off. For example, if an interrupt signal input triggered by turning off the power switch is detected (S507; Yes), the measurement controller 80 cuts off the supply of drive power to the MPU, etc., and ends this series of measurement control processes. If such an interrupt signal input is not detected (S507; No), it is necessary to continue measuring the dimensions of another workpiece W to be measured without turning off the power switch, so the process returns to step S503 and the dimension information measurement process is performed again.

As described above, the constant temperature measurement system 10' according to the second embodiment includes the measurement device 20' equipped with the measurement unit 30', the cooling and heating devices 40, 50, the temperature sensors 61 to 63, the temperature controller 70, the measurement controller 80, the display 90, and the measurement preparation completion button 100. In a temperature matching state due to the temperature matching control, the measurement controller 80 compares the master dimensional information output from the measurement unit 30' of the measurement device 20' as dimensional information by measuring the master work M with the work dimensional information output from the measurement unit 30' of the measurement device 20' as dimensional information by measuring the measured work W, and outputs the dimensional error between the two (S709), determines whether the dimensional error is within a predetermined range (S705), and outputs the result (S707, S708). This makes it possible to automate the inspection of the shape and dimensions of the measured work W. Therefore, without installing large-scale equipment, it is possible to measure the shape and dimensions of the workpiece W to be measured, which is precisely temperature-controlled so as to be less susceptible to the effects of thermal expansion and contraction, and it is also possible to automatically perform inspections of the shape and dimensions of the workpiece W to be measured and to determine whether or not the shape and dimensions are good.

In the second embodiment described above, in the OK/NG process (FIG. 7C) of the measurement control process executed by the measurement controller 80, the dimensional error calculation process (S703) and the error information output process (S709) are performed as processes for "comparing the master dimensional information with the workpiece dimensional information and outputting the dimensional error between the two", and the pass/fail determination process (S705), the pass information output process (S707), and the fail information output process (S708) are also performed as processes for "determining whether the dimensional error is within a predetermined range". However, the algorithm of the OK/NG process may be configured to perform only one of the processes in steps S703 and S709 and the processes in steps S705 to S708. In addition, the output destination of this information is not limited to the display 90, but may be an information processing device including other controllers (control devices), a personal computer, etc., or an information communication network using electric communication lines including a LAN, a LPWAN (Low-Power Wide-Area Network), a WAN, etc.

In the above-mentioned second embodiment, an example was given of an inspection process in which a person in charge confirms that the temperatures of the workpieces W, M and the support 23 of the measuring device 20 have reached a specific temperature by viewing the display 90, etc., and then removes the measured workpiece W from the cooling device 40 and sets it on the measuring table 21 of the measuring device 20, and after setting is complete, presses the measurement preparation completion button 100, etc. In other words, a case in which the inspection process is performed semi-automatically was described. However, for example, when it is necessary to significantly reduce the amount of work required by the inspector, there may be a need to perform the inspection process fully automatically. In such a case, for example, by configuring as follows, it is possible to realize an inspection system (or constant temperature measurement system) in which the inspection process is fully automated.

For example, in this inspection system (or constant temperature measurement system), instead of the display 90 and measurement preparation completion button 100 of the constant temperature measurement system 10' of the second embodiment, a robot (not shown) capable of transporting the measured workpiece W or the master workpiece M by gripping or suction, and a robot controller (not shown) for controlling the robot are provided, and the robot controller is connected to the measurement controller 80. That is, constant temperature completion information, master dimension storage information, pass information, fail information, and error information output from the measurement controller 80 are input to the robot controller of the robot, and preparation completion information is output from the robot controller and input to the measurement controller 80. The robot may be a cylindrical coordinate robot, a Cartesian coordinate robot, a horizontal multi-joint robot, a vertical multi-joint robot, a parallel link robot, etc.

The robot controller that controls the robot is preprogrammed to cause the robot to take out the workpieces W, M from a workpiece stocker (not shown) or the like and place them on the cooling and heating devices 40, 50, take out the workpieces W, M at a particular temperature from the cooling and heating devices 40, 50 and set them on the measurement table 21 of the measuring device 20, take out the measured workpieces W, M from the measuring device 20 and transport them to different work trays (good product tray, defective product tray) or the like depending on the pass/fail judgment result.

By configuring the inspection system (or constant temperature measurement system) in this way, in conjunction with the measurement control process etc. described in the second embodiment, the robot controller performs control processes for the robot etc. in the following order, for example. Note that the numbers in parentheses are the numbers of the processing steps in the measurement control process etc. described in the second embodiment.

(1) The robot transports the master workpiece M to the cooling device 50.
(2) When constant temperature completion information is output from the measurement controller 80 to the robot controller (S605), the robot removes the master work M, which has reached the specific temperature, from the cooling and heating device 50 and transports it to the measurement device 20.
(3) When the transfer of the workpiece W to be measured by the robot is completed, the robot controller outputs preparation completion information to the measurement controller 80 (S607; Yes).
(4) When the master dimension information is stored and the master dimension stored information is output from the measurement controller 80 to the robot controller (S613), the robot takes out the master workpiece M from the measuring device 20 and transports it to the cooling/heating device 50.
(5) The robot takes out the workpiece W to be measured from a workpiece stocker or the like and transports it to the cooling device 40.
(6) When constant temperature completion information is output from the measurement controller 80 to the robot controller (S605), the robot removes the measured workpiece W that has reached the specific temperature from the cooling and heating device 40 and transports it to the measurement device 20.
(7) When the transfer of the workpiece W to be measured by the robot is completed, the robot controller outputs preparation completion information to the measurement controller 80 (S607; Yes).
(8) When pass information is output from the measurement controller 80 to the robot controller (S707), the robot takes out the measured workpiece W from the measuring device 20 and transfers it to the non-defective product tray.
(9) When rejection information is output from the measurement controller 80 to the robot controller (S708), the robot takes out the measured workpiece W from the measuring device 20 and transfers it to the reject tray.
(10) The error information output from the measurement controller 80 to the robot controller is stored in the robot controller.
(11) If the power is not turned off (S507; No), return to (5) above.

The above-mentioned inspection system (or constant temperature measurement system) can be understood as a creation of a technical idea as follows.
a measuring device that measures the shape and dimensions of an object to be measured and outputs dimensional information;
a measurement controller to which the dimensional information is input;
a first cooling/heating unit for cooling or heating a master work having a reference shape;
a first temperature sensor that measures the temperature of the master work and outputs master temperature information;
A second cooling/heating unit for cooling or heating the measuring device;
a second temperature sensor that measures the temperature of the measuring device and outputs measuring device temperature information;
A third cooling/heating unit that cools or heats the workpiece to be measured;
A third temperature sensor that measures the temperature of the workpiece to be measured and outputs workpiece temperature information;
a temperature controller that receives the master temperature information, the measuring device temperature information, and the workpiece temperature information and controls output temperatures of the first cooling/heating unit, the second cooling/heating unit, and the third cooling/heating unit based on the temperature information;
a robot that transports the master workpiece to the first cooling/heating unit and the measuring device, and transports the measured workpiece to the third cooling/heating unit and the measuring device;
A robot controller for controlling the robot,
the temperature controller controls output temperatures of the first cooling/heating unit, the second cooling/heating unit, and the third cooling/heating unit so that the temperatures of the master work, the measured work, and the measuring device each coincide with a predetermined temperature, and outputs temperature coincidence information when each of the temperatures coincides with the predetermined temperature;
When the temperature coincidence information is output, the measurement controller compares master dimensional information output from the measuring device as the dimensional information by measuring the master workpiece with workpiece dimensional information output from the measuring device as the dimensional information by measuring the measured workpiece, determines whether or not a dimensional error between the two is within a predetermined range, and outputs information on the determination result.
the robot controller controls the robot to transport the master work from the first cooling/heating unit to the measuring device, or transport the measured work from the third cooling/heating unit to the measuring device, based on the temperature matching information, and to transport the measured work from the measuring device to a predetermined first location if the dimensional error is within a predetermined range, or to transport the measured work from the measuring device to a predetermined second location if the dimensional error is not within the predetermined range, based on the judgment result information.
1. An inspection system (or constant temperature measurement system) comprising:

The above-mentioned inspection system (or constant temperature measurement system) includes a measuring device, a first cold/hot unit, a first temperature sensor, a second cold/hot unit, a second temperature sensor, a third cold/hot unit, a third temperature sensor, a temperature controller, a measurement controller, a robot, and a robot controller. The temperature controller controls the output temperatures of the first cold/hot unit, the second cold/hot unit, and the third cold/hot unit so that the temperatures of the master work, the measured work, and the measuring device coincide with the predetermined temperatures, respectively, and outputs temperature coincidence information when the temperatures coincide with the predetermined temperatures. In addition, when the temperature coincidence information is output, the measurement controller compares the master dimensional information output from the measuring device as dimensional information by measuring the master work and the work dimensional information output from the measuring device as dimensional information by measuring the measured work, and determines whether the dimensional error between the two is within a predetermined range, and outputs the determination result information. Furthermore, the robot controller controls the robot to transport the master workpiece from the first cooling/heating unit to the measuring device or transport the measured workpiece from the second cooling/heating unit to the measuring device based on the temperature matching information, and to transport the measured workpiece from the measuring device to a predetermined first location if the dimensional error is within a predetermined range based on the judgment result information, or to transport the measured workpiece from the measuring device to a predetermined second location if the dimensional error is not within the predetermined range. The predetermined first location is, for example, a non-defective product tray, and the predetermined second location is, for example, a defective product tray.

As a result, even if the temperatures of the three, such as the master work, are different, the master work, the measured work, and the measuring device are cooled or heated, and the temperatures of these three can be adjusted to a predetermined temperature with high precision. In addition, the robot that transports the master work to the first cold-heat unit or the measuring device, or the measured work to the third cold-heat unit or the measuring device, transports the master work from the first cold-heat unit to the measuring device, or transports the measured work from the third cold-heat unit to the measuring device, based on the temperature coincidence information. In addition, based on the judgment result information, the robot transports the measured work from the measuring device to a predetermined first location (e.g., a non-defective product tray) if the dimensional error is within a predetermined range, and transports the measured work from the measuring device to a predetermined second location (e.g., a defective product tray) if the dimensional error is not within the predetermined range. Therefore, it is possible to measure the shape and dimensions of the measured object, which are precisely temperature-controlled so as to be less susceptible to the effects of thermal expansion and thermal contraction, without providing any large-scale equipment, and it is also possible to realize full automation of the inspection process based on the dimensional information obtained by the measurement. This makes the inspection process almost entirely manual, significantly reducing the amount of work required by inspectors.

In the above-mentioned first and second embodiments, a Peltier unit 27 or a fan unit 29 is provided on the support 23 of the measuring device 20 as a second cooling/heating unit for cooling or heating the measuring device. However, if there is a possibility that a part of the measuring device may thermally expand or contract due to a temperature change in the measuring device or its surrounding space, which may affect the measurement of the shape and dimensions by the measuring device, the Peltier unit 27 or the fan unit 29 may be provided on the bracket 25 of the measuring device 20 or the spindle 32 of the measuring unit 30 as a part of the measuring device. In this case, as in the above, it is possible to match (align) the temperatures of these three with high precision and in a short time without providing a cooling/heating unit in the measuring device 20, etc., and it is possible to measure the shape and dimensions of the workpieces W and M whose temperatures are precisely controlled so as to be less susceptible to the effects of thermal expansion and thermal contraction without providing large-scale equipment.

In the above-mentioned first and second embodiments, the temperature sensor 63 is attached to the support 23 of the measuring device 20 as the third temperature sensor for measuring the temperature of the measuring device, and the temperature of the support 23 is measured. However, the third temperature sensor may be configured to measure the ambient temperature of the measuring device. That is, the temperature sensor 63 is exposed to the surrounding space without contacting the measuring device 20, and the temperature sensor 63 (third temperature sensor) measures the ambient temperature of the measuring device 20 (measuring device) and outputs the surrounding space temperature information. Even in this configuration, by replacing the above-mentioned measuring device temperature information with the surrounding space temperature information, it is possible to measure the shape and dimensions of the workpieces W and M whose temperature is precisely controlled so as to be less susceptible to the effects of thermal expansion and thermal contraction without providing large-scale equipment, as described above.

In the above-mentioned first and second embodiments, the Peltier units 43, 53, 145, 27 are provided in the cooling device 40, 50, etc. as heat absorbers and heat generators of the first to third cooling and heating units that cool or heat the master work, the work to be measured, and the measuring device. However, if it is possible to absorb heat or generate heat, for example, a cooling unit or a heat generating unit that can absorb heat or generate heat by flowing cold water or hot water through it may be provided in the support 23 of the cooling device 40, 50 or the measuring device 20, 20'.

In addition, in the first and second embodiments described above, the temperature controller 70 is described as having one MPU, but it may be configured, for example, so that the temperature controller 70 has multiple MPUs and each of the tasks described above (constant temperature control task, cold/hot control task, Peltier drive control task) is shared and executed by the multiple MPUs. This reduces the information processing load on the MPU, making it possible to shorten the processing time and speed up the response speed to the temperature information measured by the temperature sensors 61 to 63.

Furthermore, in the first and second embodiments described above, the cold/hot cavities 41, 51, 141 of the cooling/hot devices 40, 50, 140 are made of relatively inexpensive metals with high thermal conductivity (e.g., copper, aluminum, etc.), but if high thermal conductivity is given top priority when selecting a metal material, the cold/hot cavities 41, 51, 141 may be made of silver. Also, if metal is not required, the cold/hot cavities 41, 51, 141 may be made of carbon nanotubes. This makes it possible to transmit cooling or heating by the Peltier units 43, 53, 145 to the workpieces W, M in an even shorter time.

Although specific examples of the present invention have been described above in detail, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications or changes to the above specific examples. Furthermore, the technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology exemplified in this specification or drawings achieves multiple objectives simultaneously, and achieving one of these objectives is itself technically useful. Note that the descriptions in parentheses in the [Explanation of symbols] column may clearly indicate the correspondence between the terms used in each of the above-mentioned embodiments and the terms described in the claims. In some cases, the correspondence with the claims in the claims is clearly indicated.

10, 10'... Constant temperature measurement system 20, 20'... Measurement device (measurement device)
27... Peltier unit (second heating/cooling unit (claims 1 and 3), Peltier module)
30, 30'...Measuring unit (measuring device)
31, 31': Main body 32: Spindle 33: Measuring element 35: Display 40: Cooling device (second cooling/heating unit (claim 2), third cooling/heating unit (claim 3))
50... Cooling device (first cooling unit (claims 1 to 3))
140... Cooling device (first cooling unit (claims 1 to 3), second cooling unit (claim 2), third cooling unit (claim 3))
41, 51, 141... cold/hot cavity 43, 53, 145... Peltier unit (Peltier module)
61...Temperature sensor (third temperature sensor (claims 1 and 2), second temperature sensor (claim 3))
62...Temperature sensor (first temperature sensor (claims 1 to 3))
63...Temperature sensor (second temperature sensor (claims 1 and 2), third temperature sensor (claim 3))
70: Temperature controller 80: Measurement controller 90: Display M: Master work W: Work to be measured X: Object to be measured SP: Internal space MO: Machine oil

Claims (6)

a measuring device that measures the shape and dimensions of an object to be measured and outputs dimensional information;
a first cooling/heating unit for cooling or heating a master work having a reference shape;
a first temperature sensor that measures the temperature of the master work and outputs master temperature information;
A second cooling/heating unit for cooling or heating the measuring device;
a second temperature sensor that measures the temperature of the measuring device and outputs measuring device temperature information;
A third temperature sensor that measures the temperature of a workpiece to be measured and outputs workpiece temperature information;
a temperature controller to which the master temperature information, the workpiece temperature information, and the measuring device temperature information are input and which controls the output temperatures of the first cooling/heating unit and the second cooling/heating unit based on the temperature information;
The temperature controller controls the output temperature of the first cooling/heating unit so that the temperature of the master work matches the temperature of the work to be measured, and controls the output temperature of the second cooling/heating unit so that the temperature of the measuring device matches the temperature of the work to be measured, as a temperature matching control. a measuring device that measures the shape and dimensions of an object to be measured and outputs dimensional information;
a first cooling/heating unit for cooling or heating a master work having a reference shape;
a first temperature sensor that measures the temperature of the master work and outputs master temperature information;
a second temperature sensor that measures the temperature of the measuring device and outputs measuring device temperature information;
A second cooling/heating unit that cools or heats the workpiece to be measured;
A third temperature sensor that measures the temperature of the workpiece to be measured and outputs workpiece temperature information;
a temperature controller to which the master temperature information, the measuring device temperature information, and the workpiece temperature information are input and which controls the output temperatures of the first cooling/heating unit and the second cooling/heating unit based on the temperature information;
The temperature controller controls the output temperature of the first cooling/heating unit so that the temperature of the master work matches the temperature of the measuring device, and controls the output temperature of the second cooling/heating unit so that the temperature of the measured work matches the temperature of the measuring device, as a temperature matching control. a measuring device that measures the shape and dimensions of an object to be measured and outputs dimensional information;
a first cooling/heating unit for cooling or heating a master work having a reference shape;
a first temperature sensor that measures the temperature of the master work and outputs master temperature information;
A second cooling/heating unit for cooling or heating the measuring device;
a second temperature sensor that measures the temperature of the measuring device and outputs measuring device temperature information;
A third cooling/heating unit that cools or heats the workpiece to be measured;
A third temperature sensor that measures the temperature of the workpiece to be measured and outputs workpiece temperature information;
a temperature controller to which the master temperature information, the measuring device temperature information, and the workpiece temperature information are input and which controls output temperatures of the first cooling/heating unit, the second cooling/heating unit, and the third cooling/heating unit based on these temperature information;
The temperature controller controls the output temperatures of the first cold/hot unit, the second cold/hot unit, and the third cold/hot unit as temperature matching control so that the temperatures of the master work, the measured work, and the measuring device each match a predetermined specified temperature. The constant temperature measurement system according to claim 1 or 2, characterized in that the first and second cooling and heating units are equipped with Peltier modules whose cooling or heating is controlled by the temperature controller. The constant temperature measurement system according to claim 3, characterized in that the first cooling/heating unit, the second cooling/heating unit, and the third cooling/heating unit are equipped with Peltier modules whose cooling or heating is controlled by the temperature controller. a measurement controller to which the dimensional information is input;
The constant temperature measurement system according to any one of claims 1 to 5, characterized in that, in a temperature matching state due to the temperature matching control, the measurement controller compares master dimensional information output from the measuring device as the dimensional information by measuring the master work and work dimensional information output from the measuring device as the dimensional information by measuring the measured work, and outputs a dimensional error between the two, or determines whether the dimensional error is within a predetermined range and outputs the result.

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