Mechanical device and temperature management system

Abstract

A mechanical device 20 includes a shaft member 31, a bearing 42 that rotatably supports the shaft member 31, and an RFID tag 33a that has a temperature sensor 33b for detecting a temperature of the shaft member 31 and that transmits the temperature detected by the temperature sensor 33b to a reader / writer 3.

Description

Mechanical and temperature control systems

[0001] The present disclosure relates to mechanical devices and thermal management systems.

[0002] Patent Document 1 discloses a bearing unit for a conveying device as an example of a mechanical device. The mechanical device in Patent Document 1 includes a housing, a bearing disposed in the housing, a sensor for detecting the condition of the bearing, and a transmitter for wirelessly transmitting information detected by the sensor.

[0003] The bearing, sensor, and transmitter are disposed within a housing. The sensor is, for example, a temperature sensor that detects the temperature of the bearing. If the condition of the bearing changes, the temperature of the bearing rises, which can cause a bearing abnormality. The mechanical device of Patent Document 1 can contribute to detecting a bearing abnormality based on the temperature detected by the temperature sensor.

[0004] JP 2013-11312 A

[0005] The mechanical device of Patent Document 1 further includes a cover that covers the sensor and transmitter inside the housing, and a seal member that prevents dust and other particles from entering between the housing and the cover. The presence of the sensor and other components inside the housing increases the number of components in the mechanical device of Patent Document 1, making it difficult to simplify the design. Furthermore, in mechanical devices that have a shaft member and a bearing that rotate relative to each other, there is a demand for early detection of mechanical device abnormalities. This also applies to mechanical devices that have two components that are capable of relative movement.

[0006] The present disclosure aims to simplify the configuration of a mechanical device having two members capable of relative movement, and a temperature control system equipped with such a mechanical device, and to enable early detection of abnormalities in the mechanical device.

[0007] A mechanical device according to one aspect of the present disclosure comprises a first member, a second member to which the first member is attached so as to be able to move relative to the second member, and an RFID tag having a temperature sensor that detects the temperature of the first member and transmits the temperature detected by the temperature sensor to a reader / writer.

[0008] According to this, the temperature sensor is disposed on the first member, and the temperature detected by the temperature sensor is transmitted to the reader / writer. Therefore, the temperature detected by the temperature sensor can be output with a simple configuration. Furthermore, the temperature detected by the temperature sensor can be output regardless of the position of the temperature sensor. Therefore, the configuration of the mechanical device can be simplified.

[0009] Furthermore, when the temperature of the first member rises, the dimensional relationship between the first member and the second member changes. This can lead to an abnormality occurring in one of the first member or the second member. In other words, by detecting the temperature of the first member using a temperature sensor, it is possible to contribute to earlier detection of an abnormality in a mechanical device based on the temperature of the first member.

[0010] Furthermore, in a mechanical device according to one aspect of the present disclosure, the first member is an axial member, the second member is a bearing that rotatably supports the first member, and the temperature sensor is arranged on an end face of the first member.

[0011] As a result, even when the mechanical device is equipped with an axial member and a bearing that rotatably supports the axial member, as described above, the configuration of the mechanical device can be simplified and this can contribute to earlier detection of abnormalities in the mechanical device based on the temperature of the screw shaft.

[0012] Furthermore, when the temperature sensor is disposed on the end face of the shaft member, the centrifugal force acting on the temperature sensor can be reduced compared to when the temperature sensor is disposed on the outer circumferential surface of the shaft member, thereby reducing the risk of failure of the temperature sensor.

[0013] In addition, in a mechanical device according to one aspect of the present disclosure, the first member is a screw shaft, the second member is a nut that is fitted to the first member so as to be rotatable relative to the first member, and the temperature sensor is arranged on an end face of the first member.

[0014] This makes it possible to simplify the configuration of the mechanical device, as described above, even when the mechanical device is equipped with a screw shaft and a nut that is fitted to the screw shaft so that it can rotate relative to the screw shaft, and also contributes to earlier detection of abnormalities in the mechanical device based on the temperature of the screw shaft.

[0015] Furthermore, when the temperature sensor is disposed on the end face of the screw shaft, the centrifugal force acting on the temperature sensor can be reduced compared to when the temperature sensor is disposed on the outer circumferential surface of the screw shaft, thereby reducing the risk of failure of the temperature sensor.

[0016] Furthermore, in a mechanical device according to one aspect of the present disclosure, the mechanical device further includes a plurality of rolling elements that roll between the first member and the second member, the second member being a guide rail, the first member being a slider attached to the second member so as to be slidable relative to the second member, and having a circulation path through which the rolling elements circulate, and when the first member is viewed along a direction perpendicular to the sliding direction of the first member, the temperature sensor overlaps the circulation path.

[0017] This allows for simplification of the configuration of the mechanical device, as described above, even when the mechanical device is equipped with a guide rail and a slider that is slidably attached to the guide rail, and contributes to earlier detection of abnormalities in the mechanical device based on the temperature of the slider.

[0018] Furthermore, the temperature of the slider's contacting portion with the rolling element rises earlier than the temperature of other portions. Therefore, the portion of the slider's outer surface where the temperature sensor is located rises earlier in response to the temperature rise of the slider. Therefore, the mechanical device can reliably contribute to early detection of abnormalities by the temperature detected by the temperature sensor.

[0019] In addition, in a mechanical device according to one aspect of the present disclosure, the first member is a screw shaft, the second member is a nut that is fitted to the first member so as to be rotatable relative to the first member, and the mechanical device further includes a second RFID tag that has a second temperature sensor that detects the temperature of the second member and transmits the temperature detected by the second temperature sensor to a reader / writer.

[0020] According to this, even when the mechanical device is equipped with a screw shaft and a nut that is fitted to the screw shaft so that it can rotate relative to the screw shaft, as described above, the configuration of the mechanical device can be simplified and it can contribute to earlier detection of abnormalities in the mechanical device based on the temperature of the screw shaft and the temperature of the nut.

[0021] Furthermore, a temperature management system according to one aspect of the present disclosure includes the above-described mechanical device, the reader / writer, and a control device electrically connected to the reader / writer and configured to store the temperature detected by the temperature sensor.

[0022] With this, the reader / writer easily obtains the temperature detected by the temperature sensor from the mechanical device. Therefore, the control device can easily obtain the temperature detected by the temperature sensor via the reader / writer. Therefore, the temperature management system can achieve early detection of abnormalities in the mechanical device with a simple configuration.

[0023] Moreover, a temperature management system according to one aspect of the present disclosure includes a plurality of the mechanical devices.

[0024] This allows the control device to easily obtain the temperatures detected by the multiple temperature sensors via the reader / writer, so even when multiple mechanical devices are included in the temperature management system, the simple configuration allows for early detection of abnormalities in the mechanical devices.

[0025] In addition, in a temperature management system according to one aspect of the present disclosure, the first member is a screw shaft, the second member is a nut that is fitted to the first member so as to be rotatable relative to the first member, and the control device controls the amount of rotation of the first member and corrects the amount of rotation of the first member based on the detection result of the temperature sensor.

[0026] According to this, the control device corrects the amount of rotation of the screw shaft based on the temperature detected by the temperature sensor, thereby correcting the amount of movement of the nut, thereby suppressing the effects of temperature changes on the screw shaft in the mechanical device.

[0027] In addition, in a temperature management system according to one aspect of the present disclosure, the first member is a screw shaft, the second member is a nut that is fitted to the first member so as to be rotatable relative to the first member, the mechanical device further comprises a plurality of balls that circulate within the second member, a second RFID tag that has a second temperature sensor that detects the temperature of the second member and transmits the temperature detected by the second temperature sensor to the reader / writer, and the control device detects an abnormality in the mechanical device when the temperature difference between the temperature detected by the temperature sensor and the second temperature sensor is greater than or equal to a predetermined temperature difference.

[0028] According to this, the control device wirelessly acquires the temperature of the screw shaft and the temperature of the nut via the RFID tag, the second RFID tag, and the reader / writer. Therefore, the control device can easily acquire the temperature of the screw shaft and the temperature of the nut even when the screw shaft is rotating. Therefore, the control device can easily manage the temperature of the screw shaft and the temperature of the nut.

[0029] Furthermore, for example, if the temperature of the nut rises due to friction between the nut and the ball, the temperature difference between the nut and the screw shaft becomes relatively large. As a result, if the difference between the thermal expansion of the nut and the thermal expansion of the screw shaft becomes large, the friction between the screw shaft and the ball and between the nut and the ball becomes relatively large, which may shorten the life of the mechanical device. Therefore, the control device detects an abnormality in the mechanical device when the temperature difference between the screw shaft and the nut is equal to or greater than a predetermined temperature difference. Therefore, the temperature management system can prevent the life of the mechanical device from being shortened.

[0030] In addition, in a temperature control system according to one aspect of the present disclosure, the RFID tag is disposed on an end surface of the first member.

[0031] This reduces the centrifugal force acting on the RFID tag compared to when the RFID tag is disposed on the outer circumferential surface of the screw shaft, thereby preventing the RFID tag from breaking down.

[0032] In addition, in a temperature management system according to one aspect of the present disclosure, the second member comprises a main body portion having a through hole through which the first member passes, and a plurality of circulation members that form a passage for the ball, each of the plurality of circulation members having a protrusion that protrudes from the main body portion, and the second RFID tag is positioned in a position on the main body portion between two of the plurality of protrusions.

[0033] When the friction between the circulating member and the balls becomes relatively large, the temperature of the circulating member rises relatively quickly. Therefore, the second temperature sensor of the second RFID tag detects the temperature rise of the circulating member early. As a result, the temperature difference between the detection result of the first temperature sensor and the detection result of the second temperature sensor becomes large early. Therefore, the temperature management system can detect abnormalities in the mechanical device early.

[0034] In addition, in a temperature management system according to one aspect of the present disclosure, the second temperature sensor overlaps with the ball passage of the second member when viewed along the radial direction of the first member.

[0035] According to this, when the temperature of the nut rises due to friction between the ball and the nut, the temperature of the nut rises relatively quickly near the ball passage. Therefore, the second temperature sensor detects the temperature rise of the nut near the ball passage early. As a result, the temperature difference between the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor becomes large early. Therefore, the temperature management system can detect abnormalities in the mechanical device early.

[0036] Furthermore, a temperature management system according to one aspect of the present disclosure includes a plurality of the second RFID tags, and the plurality of second RFID tags are arranged in a row along the central axis of the first member.

[0037] This allows the user to easily obtain the temperatures detected by the multiple second temperature sensors by moving the reader / writer along the central axis of the screw shaft, thereby making it easy to manage the temperature of the nut.

[0038] In addition, a temperature management system according to one aspect of the present disclosure includes a plurality of the second RFID tags, and the control device detects an abnormality in the mechanical device when the temperature difference between the detection result of the second temperature sensor of at least one of the plurality of second RFID tags and the detection result of the temperature sensor is greater than or equal to a predetermined temperature difference.

[0039] This allows early detection of an abnormality in the mechanical device even if there is an abnormality in a part of the mechanical device.

[0040] According to the present disclosure, in a mechanical device having two members capable of relative movement, and in a temperature control system including such a mechanical device, it is possible to simplify the configuration and to detect abnormalities in the mechanical device more quickly.

[0041] FIG. 1 is a diagram illustrating a configuration of a temperature management system according to a first embodiment of the present disclosure. FIG. 2 is a diagram illustrating the mechanical device illustrated in FIG. 1 as viewed along the central axis of a shaft member. FIG. 3 is a cross-sectional view of the mechanical device taken along line III-III illustrated in FIG. 2. FIG. 4 is a plan view of a temperature detection device illustrated in FIG. 2. FIG. 5 is an enlarged cross-sectional view of the temperature detection device illustrated in FIG. 3. FIG. 6 is a block diagram of an RFID tag. FIG. 7 is a cross-sectional view of a temperature detection device in a mechanical device according to a first modified example of the first embodiment of the present disclosure. FIG. 8 is a cross-sectional view of a temperature detection device in a mechanical device according to a second modified example of the first embodiment of the present disclosure. FIG. 9 is a cross-sectional view of a temperature detection device in a mechanical device according to a third modified example of the first embodiment of the present disclosure. FIG. 10 is a diagram illustrating a configuration of a temperature management system according to a second embodiment of the present disclosure. FIG. 11 is a side view of the ball screw illustrated in FIG. 10. FIG. 12 is a diagram illustrating a configuration of a temperature management system according to a third embodiment of the present disclosure. FIG. 13 is a diagram illustrating a configuration of the mechanical device illustrated in FIG. 12. FIG. 14 is a cross-sectional view of the mechanical device taken along line XIV-XIV illustrated in FIG. 13. Fig. 15 is a diagram showing a cross section of the temperature detection device shown in Fig. 14. Fig. 16 is a diagram showing the configuration of a temperature management system according to a fourth embodiment of the present disclosure. Fig. 17 is a side view of a mechanical device as seen along arrow XVII shown in Fig. 16. Fig. 18 is a diagram showing a cross section of the first temperature detection device shown in Fig. 16. Fig. 19 is a partial cross section along the central axis of a mechanical device included in a temperature management system according to a modified example of the fourth embodiment of the present disclosure. Fig. 20 is a cross section of the mechanical device along line XX-XX shown in Fig. 19.

[0042] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings, but the present disclosure is not limited thereto. The components of each embodiment and each modified example described below can be combined as appropriate. In addition, some components may not be used.

[0043] 1 is a diagram showing the configuration of a temperature management system 1 according to a first embodiment of the present disclosure. The temperature management system 1 of the first embodiment is a system that manages the temperature of a bearing 42 (described later) and detects an abnormality in the bearing 42, i.e., an abnormality in the mechanical device 20.

[0044] The temperature control system 1 includes a transport device 2, a reader / writer 3, and a control device 4. The temperature control system 1 may include a plurality of transport devices 2.

[0045] The conveying device 2 is a roller conveyor that conveys industrial products along a conveying direction W. The conveying device 2 includes a pair of support tables 10 and a plurality of mechanical devices 20. In this embodiment, the number of mechanical devices 20 is 10, but it goes without saying that the number is not limited to this.

[0046] The pair of support tables 10 support a plurality of mechanical devices 20. The pair of support tables 10 are shaped like rectangular parallelepipeds extending along the conveying direction W.

[0047] The mechanical device 20 includes a roller member 30 and a pair of mechanical components 40 .

[0048] The roller member 30 includes a shaft member 31 (corresponding to the "first member" in the first embodiment) and a roller 32. The shaft member 31 has a cylindrical shape extending along a central axis Ax (see FIGS. 2 and 3 described below). An RFID (Radio Frequency Identification) tag 33a that is integral with a temperature sensor 33b (described below) is attached to the shaft member 31. The temperature sensor 33b and the RFID tag 33a will be described in detail below.

[0049] The rollers 32 are cylindrical and disposed on the circumferential surface of the shaft member 31, and rotate integrally with the shaft member 31. Both ends of the shaft member 31 are exposed from the rollers 32.

[0050] The pair of mechanical components 40 support the roller member 30 so as to be rotatable relative to one another. Specifically, the pair of mechanical components 40 support both ends of the shaft member 31 so as to be rotatable relative to one another. The mechanical components 40 are plummer blocks. The mechanical components 40 include bearings 42 (corresponding to the "second member" in the first embodiment). Details of the mechanical components 40 will be described later.

[0051] The pair of mechanical components 40 are fixed to the pair of support bases 10 using, for example, fixing bolts, so that the plurality of mechanical devices 20 are supported by the pair of support bases 10. The plurality of mechanical devices 20 are arranged such that the central axes Ax of the shaft members 31 are parallel to each other and perpendicular to the conveying direction W.

[0052] The reader / writer 3 performs wireless communication with an RFID tag 33a provided in the mechanical device 20. The reader / writer 3 is portable by the user. The reader / writer 3 is electrically connected to the control device 4 by wire or wirelessly.

[0053] A user operates the reader / writer 3, and the reader / writer 3 transmits a carrier wave to the RFID tag 33a. In response, the RFID tag 33a transmits the temperature detected by the temperature sensor 33b (hereinafter referred to as the temperature detected by the temperature sensor 33b) to the reader / writer 3. The reader / writer 3 acquires the temperature detected by the temperature sensor 33b and transmits it to the control device 4.

[0054] The reader / writer 3 can simultaneously communicate wirelessly with multiple RFID tags 33a. This allows the reader / writer 3 to acquire the temperatures detected by the multiple temperature sensors 33b in a relatively short time. The reader / writer 3 then transmits the temperatures detected by the multiple temperature sensors 33b to the control device 4.

[0055] The control device 4 is a computer and includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an internal storage unit, an input interface, and an output interface. The CPU, ROM, RAM, and internal storage unit are connected via an internal bus. The ROM stores programs such as the BIOS. The internal storage unit is, for example, a hard disk drive (HDD) or flash memory, and stores operating system programs and application programs. The CPU uses the RAM as a work area and executes programs stored in the ROM or internal storage unit to realize various functions.

[0056] The control device 4 acquires the temperature detected by the temperature sensor 33b from the reader / writer 3. The control device 4 detects an abnormality in the bearing 42 of the mechanical component 40 before a failure occurs in the bearing 42, based on the temperature detected by the temperature sensor 33b.

[0057] An abnormality in the bearing 42 occurs when the temperature of the shaft member 31 rises and the dimensional relationship between the shaft member 31 and the bearing 42 changes (details will be described later). If the abnormality in the bearing 42 is overlooked, the bearing 42 will fail, leading to failure of the mechanical component 40. In other words, the control device 4 detects an abnormality in the bearing 42 that occurs before the bearing 42 fails.

[0058] If the temperature detected by the temperature sensor 33b is equal to or higher than a predetermined temperature, the control device 4 determines that there is an abnormality in the bearing 42. The predetermined temperature is set, for example, to a temperature at which the bearing 42 will not be damaged, and is stored in advance in the internal storage unit of the control device 4. Based on the determination result of the control device 4, the user investigates the machine 20 determined to have an abnormality.

[0059] By periodically checking the temperature detected by the temperature sensor 33b using the control device 4, the user can detect an abnormality in the bearing 42, i.e., an abnormality in the mechanical device 20, at an early stage.

[0060] As described above, according to this embodiment, the temperature management system 1 comprises a mechanical device 20, a reader / writer 3, and a control device 4 electrically connected to the reader / writer 3 and storing the detected temperature of the temperature sensor 33b.

[0061] This allows the reader / writer 3 to easily obtain the temperature detected by the temperature sensor 33b from the mechanical device 20. Therefore, the control device 4 can easily obtain the temperature detected by the temperature sensor 33b via the reader / writer 3. Therefore, the temperature management system 1 can achieve early detection of an abnormality in the mechanical device 20 with a simple configuration.

[0062] The temperature control system 1 also includes a plurality of mechanical devices 20 .

[0063] This allows the control device 4 to easily obtain the temperatures detected by the multiple temperature sensors 33b via the reader / writer 3. Therefore, even when the temperature management system 1 includes multiple mechanical devices 20, it is possible to quickly detect abnormalities in the mechanical devices 20 with a simple configuration.

[0064] <Mechanical device 20> In the following description, the Z direction shown in the drawings is the up-down direction of the mechanical component 40, the X direction is the left-right direction of the mechanical component 40, and the Y direction is the front-rear direction of the mechanical component 40. The X direction, Y direction, and Z direction are perpendicular to one another. The central axis Ax of the shaft member 31 extends along the Y direction. Note that the X, Y, and Z directions are merely examples, and the present disclosure is not limited to these directions.

[0065] Fig. 2 is a view of the mechanical device 20 shown in Fig. 1 as viewed along the central axis Ax of the shaft member 31. Fig. 3 is a cross-sectional view of the mechanical device 20 taken along line III-III shown in Fig. 2. The rollers 32 of the roller member 30 are omitted in Figs. 2 and 3.

[0066] 2 and 3, the roller member 30 includes a temperature detector 33. The temperature detector 33 is disposed on the shaft member 31 and detects the temperature of the shaft member 31. The temperature detector 33 is disposed on an end surface F1 of the shaft member 31.

[0067] Fig. 4 is a plan view of the temperature detecting device 33 shown in Fig. 2. Fig. 5 is an enlarged cross-sectional view of the temperature detecting device 33 shown in Fig. 3. Fig. 6 is a block diagram of the RFID tag 33a.

[0068] The temperature detection device 33 includes an RFID tag 33a, a temperature sensor 33b, a cover member 33c, and an adhesive member 33d. The RFID tag 33a is integral with the temperature sensor 33b.

[0069] The RFID tag 33a is a passive RFID tag and includes a substrate 33a1 shown in Fig. 5. The substrate 33a1 is provided with a temperature sensor 33b, an antenna 33e shown in Fig. 6, and a control circuit 33f.

[0070] The temperature sensor 33b detects the temperature of the shaft member 31. That is, the temperature detected by the temperature sensor 33b corresponds to the temperature detected by the temperature detection device 33.

[0071] 5, the temperature sensor 33b is disposed on the main surface 33a2 of the substrate 33a1. When the temperature detection device 33 is disposed on the shaft member 31, the temperature sensor 33b faces the end face F1 of the shaft member 31. There is a space between the temperature sensor 33b and the end face F1 of the shaft member 31. This prevents vibrations from the shaft member 31 from being transmitted to the temperature sensor 33b, thereby preventing failure of the temperature sensor 33b.

[0072] 6 is electrically connected to the temperature sensor 33b and the antenna 33e. The antenna 33e receives a carrier wave from the reader / writer 3. The control circuit 33f is driven by power generated by the carrier wave.

[0073] The control circuit 33f acquires the temperature detected by the temperature sensor 33b and stores it in the memory area 33f1. The control circuit 33f transmits the temperature detected by the temperature sensor 33b stored in the memory area 33f1 to the reader / writer 3 via the antenna 33e.

[0074] The control circuit 33f also transmits identification information (e.g., an identification number) that identifies the mechanical device 20 in association with the temperature detected by the temperature sensor 33b to the reader / writer 3. The identification information is stored in advance in the memory area 33f1 by the reader / writer 3. The control device 4 stores the temperature detected by the temperature sensor 33b in association with the identification information. Thus, the control device 4 can identify the mechanical device 20 that has been determined to have an abnormality in the bearing 42.

[0075] 5 protects the RFID tag 33a. The cover member 33c is flat and includes an arrangement surface 33c1. The arrangement surface 33c1 is flat. The arrangement surface 33c1 has a recess 33c2 in which the RFID tag 33a is arranged. In a plan view of the cover member 33c, the recess 33c2 is located in the center of the cover member 33c.

[0076] Furthermore, when the RFID tag 33a is placed in the recess 33c2, the placement surface 33c1 of the cover member 33c and the main surface 33a2 of the substrate 33a1 are on the same plane. In other words, when the RFID tag 33a is placed in the recess 33c2, the placement surface 33c1 exists around the entire periphery of the main surface 33a2 of the substrate 33a1. Note that the placement surface 33c1 of the cover member 33c and the main surface 33a2 of the substrate 33a1 may be on different planes. Furthermore, when the RFID tag 33a is placed in the recess 33c2, the temperature sensor 33b protrudes from the placement surface 33c1.

[0077] The cover member 33c is made of a thermoplastic resin. Specifically, the cover member 33c is made of a nylon resin that is waterproof and oil-resistant. Therefore, the cover member 33c is waterproof and oil-resistant. The fact that the cover member 33c is waterproof and oil-resistant means that changes in the properties of the cover member 33c caused by water and oil and grease used in the mechanical device 20 during use of the mechanical device 20 are suppressed, and problems do not occur in the operation of the temperature sensor 33b and the RFID tag 33a.

[0078] The adhesive member 33d is disposed on the placement surface 33c1 of the cover member 33c and adheres the RFID tag 33a and the cover member 33c to the end face F1 of the shaft member 31. The adhesive member 33d is also disposed on the main surface 33a2 of the substrate 33a1. The adhesive member 33d has a third through hole 33d1 inside which the temperature sensor 33b is located. This allows the temperature sensor 33b to face the end face F1 of the shaft member 31 across a space. Furthermore, the third through hole 33d1 reduces the space between the temperature sensor 33b and the end face F1 of the shaft member 31. This allows the temperature sensor 33b to accurately detect the temperature of the shaft member 31.

[0079] The adhesive member 33d is a double-sided tape. The adhesive member 33d is waterproof. The adhesive member 33d is a so-called waterproof tape. The fact that the adhesive member 33d is waterproof means that changes in the properties of the adhesive member 33d caused by water during use of the mechanical component 40 are suppressed, and problems do not occur in the operation of the temperature sensor 33b and the RFID tag 33a.

[0080] The adhesive member 33d is disposed on the arrangement surface 33c1 of the cover member 33c around the entire periphery of the RFID tag 33a, thereby ensuring watertightness between the cover member 33c and the outer surface of the housing 41 and preventing water from adhering to the temperature sensor 33b and the RFID tag 33a.

[0081] The mechanical component 40 shown in FIGS. 2 and 3 includes a housing 41 and a bearing 42 .

[0082] The housing 41 has a main body 41a and a flange 41b formed integrally therewith. The main body 41a has a first through hole 41a1 through which the shaft member 31 passes.

[0083] The flange portions 41b are located on both sides of the main body portion 41a in the X direction. The flange portions 41b have second through holes 41b1 through which bolts pass for attaching the mechanical component 40 to the support base 10. The lower surface (the surface on the -Z side) of the housing 41 corresponds to the attachment surface F2 that comes into contact with the support base 10.

[0084] The bearing 42 is disposed in the housing 41 and supports the shaft member 31 rotatably relative to the housing 41. The axis of the bearing 42 is substantially parallel to the central axis Ax of the shaft member 31.

[0085] The bearing 42 is a ball bearing. However, the bearing 42 may be a roller bearing. The bearing 42 is disposed in the first through hole 41a1. The bearing 42 includes an outer ring 42a, an inner ring 42b, and a plurality of balls 42c.

[0086] The outer ring 42a fits into an annular groove 41a2 formed on the inner peripheral surface of the first through hole 41a1. The outer ring 42a is fixed to the housing 41. The inner ring 42b is located inside the outer ring 42a. The shaft member 31 is fixed to the inner ring 42b so as to be rotatable integrally therewith. The inner peripheral surface of the inner ring 42b is in contact with the outer peripheral surface of the shaft member 31. A plurality of balls 42c are arranged between the outer ring 42a and the inner ring 42b.

[0087] A preload is applied to the bearing 42. The preload is an axial load (a load perpendicular to the axis of the bearing 42) that causes the gap between the outer ring 42a and the balls 42c and the gap between the inner ring 42b and the balls 42c to become negative. Note that a preload does not necessarily have to be applied to the bearing 42.

[0088] When the shaft member 31 rotates relative to the housing 41, the inner ring 42b rotates relative to the outer ring 42a. At this time, the plurality of balls 42c roll relative to the outer ring 42a and the inner ring 42b.

[0089] Next, the operation of the mechanical component 40 when an abnormality occurs in the bearing 42 will be described.

[0090] 1 conveys industrial products, a load from the shaft member 31 acts on the bearing 42. The load from the shaft member 31 generates frictional forces between the balls 42c and the inner ring 42b and between the balls 42c and the outer ring 42a. If the frictional forces cause the condition of the bearing 42 to change, abnormalities such as damage to the bearing 42 may occur. If the abnormality in the bearing 42 progresses, failures such as seizure of the bearing 42 may occur.

[0091] Furthermore, when the temperature of the shaft member 31 rises, the shaft member 31 expands. When the shaft member 31 expands, the dimensional relationship between the shaft member 31 and the bearing 42 changes, and the shaft member 31 pushes the inner ring 42b apart. This changes the dimensional relationship of the bearing 42, and the frictional forces between the balls 42c and the inner ring 42b and between the balls 42c and the outer ring 42a increase. When a preload is applied to the bearing 42 as described above, the frictional forces increase more than when a preload is not applied to the bearing 42, and there is a high possibility that an abnormality such as damage to the bearing 42 will occur.

[0092] As described above, the temperature detector 33 is disposed on the shaft member 31. Therefore, the detected temperature of the temperature detector 33 rises quickly in response to the temperature rise of the shaft member 31.

[0093] As described above, the temperature detected by the temperature detector 33 is stored in the control device 4 via the reader / writer 3. Furthermore, if the temperature detected by the temperature detector 33 is equal to or higher than a predetermined temperature, the control device 4 determines that there is an abnormality in the bearing 42. Therefore, by disposing the temperature detector 33 on the shaft member 31, an abnormality in the bearing 42, i.e., an abnormality in the mechanical device 20, can be detected early.

[0094] As described above, according to this embodiment, the mechanical device 20 includes the shaft member 31, the bearing 42 that supports the shaft member 31 rotatably (allowing relative movement), and the RFID tag 33a that has a temperature sensor 33b that detects the temperature of the shaft member 31 and transmits the temperature detected by the temperature sensor 33b to the reader / writer 3. The temperature sensor 33b is disposed on the end face F1 of the shaft member 31.

[0095] According to this, the temperature sensor 33b is disposed on the shaft member 31, and the temperature detected by the temperature sensor 33b is transmitted to the reader / writer 3. Therefore, the temperature detected by the temperature sensor 33b can be output with a simple configuration. Furthermore, the temperature detected by the temperature sensor 33b can be output regardless of the position of the temperature sensor 33b. Therefore, the configuration of the mechanical device 20 can be simplified.

[0096] Furthermore, when the shaft member 31 expands due to an increase in temperature of the shaft member 31, the dimensional relationship between the shaft member 31 and the bearing 42 changes. This may cause an abnormality in the bearing 42. In other words, by detecting the temperature of the shaft member 31 using the temperature sensor 33b, it is possible to contribute to earlier detection of an abnormality in the bearing 42 and in the mechanical device 20 based on the temperature of the shaft member 31.

[0097] Furthermore, when the temperature sensor 33b is disposed on the end face F1 of the shaft member 31, the centrifugal force acting on the temperature sensor 33b can be reduced compared to when the temperature sensor 33b is disposed on the outer circumferential surface of the shaft member 31. Therefore, failure of the temperature sensor 33b can be suppressed.

[0098] Next, a temperature management system 1 and a mechanical device 20 according to a modified example of the embodiment of the present disclosure will be described, focusing mainly on the differences from the mechanical device 20 of the above-described embodiment.

[0099] For example, the temperature control system 1 may include a device including a mechanical device 20 instead of the transport device 2 .

[0100] Furthermore, the mechanical component 40 is not limited to a plummer block, but may be any mechanical component that includes a bearing 42.

[0101] The temperature detector 33 may also be disposed on the circumferential side surface of the shaft member 31 .

[0102] The RFID tag 33a may also be an active RFID tag, in which case the RFID tag 33a further includes a power source.

[0103] The adhesive member 33d may also be elastic. In this case, the adhesive member 33d includes, for example, an elastic sheet-like base material and adhesive layers disposed on both sides of the base material. The base material is formed of, for example, a foamed resin such as foamed polyethylene. When the conveying device 2 is operating, the elasticity of the adhesive member 33d can suppress vibrations transmitted from the shaft member 31 to the temperature sensor 33b and the RFID tag 33a.

[0104] The adhesive member 33d may be a hardened adhesive (for example, an epoxy adhesive) or a butyl tape that is waterproof and oil-resistant.

[0105] The temperature detecting device 33 does not necessarily have to include the adhesive member 33d. In this case, the temperature detecting device 33 is fixed to the shaft member 31 by, for example, a bolt.

[0106] The cover member 33c may be shaped to cover a part of the main surface 33a2 of the substrate 33a1 while exposing the temperature sensor 33b.

[0107] FIG. 7 is a cross-sectional view of a temperature detection device 33 in a mechanical device 20 according to a first modified example of the first embodiment of the present disclosure.

[0108] The mechanical device 20 according to the first modification further includes a thermally conductive paste 133g. The thermally conductive paste 133g is, for example, a silicon-based thermally conductive grease. It goes without saying that the thermally conductive paste 133g is not limited to a silicon-based paste, and any paste-like material may be used. The thermally conductive paste 133g may also be a thermosetting resin (e.g., epoxy resin) containing particles of Ag or other materials with relatively high thermal conductivity.

[0109] The thermally conductive paste 133g is filled into the third through hole 33d1 with the temperature detection device 33 disposed on the shaft member 31. As a result, the temperature sensor 33b and the shaft member 31 are thermally connected via the thermally conductive paste 133g.

[0110] In the mechanical device 20 according to the first modification, heat from the shaft member 31 is more efficiently transferred to the temperature sensor 33b via the thermally conductive paste 133g than in the mechanical device 20 according to the above embodiment.

[0111] 8 is a cross-sectional view of the temperature detection device 33 in the mechanical device 20 according to a second modification of the first embodiment of the present disclosure. In this second modification, the adhesive member 233d does not have the third through-hole 33d1. The adhesive member 233d covers the entire RFID tag 33a. As a result, the temperature sensor 33b is covered by the adhesive member 233d. As a result, the temperature sensor 33b and the shaft member 31 are thermally connected via the adhesive member 233d.

[0112] In the mechanical device 20 according to the second modification, heat from the shaft member 31 is more efficiently transferred to the temperature sensor 33b via the adhesive member 233d than in the mechanical device 20 according to the above embodiment. The adhesive member 233d may contain particles of Ag or other materials with relatively high thermal conductivity. In this case, heat from the shaft member 31 is more efficiently transferred to the temperature sensor 33b via the adhesive member 233d.

[0113] FIG. 9 is a cross-sectional view of the temperature detection device 33 in the mechanical device 20 according to a third modification of the first embodiment of the present disclosure. In this third modification, the shaft member 31 has a recess 331a into which the temperature sensor 33b fits. In FIG. 9, the adhesive member 33d is omitted. In this third modification, the adhesive member 33d may be, for example, a cured cyanoacrylate adhesive. In this case, the thickness of the adhesive member 33d can be reduced.

[0114] In the mechanical device 20 of the third modified example, the temperature sensor 33b is located inside the recess 331a, so that the temperature sensor 33b can detect the temperature of the shaft member 31 with higher accuracy.

[0115] Second Embodiment Temperature Control System 1a and Mechanical Device 402 Next, a temperature control system 1a and a mechanical device 402 according to a second embodiment of the present disclosure will be described, mainly focusing on differences from the temperature control system 1 of the first embodiment described above.

[0116] In the following description, the Z direction shown in the figure is the height direction of a mechanical device 402 (described later), the X direction is the left-right direction of the mechanical device 402, and the Y direction is the front-rear direction of the mechanical device 402. The X direction, Y direction, and Z direction are perpendicular to each other. Note that the X, Y, and Z directions are merely examples, and the present disclosure is not limited to these directions.

[0117] 10 is a diagram showing the configuration of a temperature control system 1a according to a second embodiment of the present disclosure. The temperature control system 1a according to the second embodiment is a system that controls the temperature of a screw shaft 431 (described later) and detects abnormalities in a bearing 440 (described later). The temperature control system 1a is applied to, for example, a machine tool that processes a workpiece.

[0118] The temperature control system 1a includes a mechanical device 402, a reader / writer 3, and a control device 4. The reader / writer 3 and the control device 4 are the same as the reader / writer 3 and the control device 4 in the first embodiment.

[0119] The machine device 402 is an XY table that moves the workpiece in the X and Y directions. The machine device 402 includes a fixed part 410, a moving part 420, and a table T on which the workpiece is placed.

[0120] The fixed part 410 includes a first base 411, a pair of first guide rails 412, and a first ball screw 430a. The pair of first guide rails 412 and the first ball screw 430a are arranged on an upper surface 411a (the surface on the +Z side) of the first base 411.

[0121] The pair of first guide rails 412 extend along the Y direction and guide the moving part 420. The first ball screw 430a includes a first screw shaft 431a and a first nut 432a.

[0122] The first screw shaft 431a extends along the Y direction. A first end of the first screw shaft 431a is supported by a first support 413. The first support 413 includes a first bearing 440a that rotatably supports the first screw shaft 431a. The first bearing 440a is a ball bearing. However, the first bearing 440a may also be a roller bearing.

[0123] A second end of the first screw shaft 431a is fixed to the output shaft of the first motor 450a so as to be rotatable together with the first screw shaft 431a. The first motor 450a rotates the first screw shaft 431a. The first motor 450a is equipped with a first rotary encoder 451a that detects the amount of rotation of the output shaft. The detection result of the first rotary encoder 451a is transmitted to the control device 4.

[0124] The first nut 432a is fitted onto the first screw shaft 431a so as to be rotatable relative to the first nut 432a. A plurality of balls are arranged inside the first nut 432a. As the first screw shaft 431a rotates, the plurality of balls circulate inside the first nut 432a. The moving part 420 is fixed to the first nut 432a. As the first screw shaft 431a rotates, the first nut 432a and the moving part 420 move along the Y direction.

[0125] The moving unit 420 includes a second base 421, a pair of second guide rails 422, and a second ball screw 430b. A first nut 432a is fixed to the −Z side surface of the second base 421. The pair of second guide rails 422 and the second ball screw 430b are disposed on the upper surface 21a (+Z side surface) of the second base 421.

[0126] The pair of second guide rails 422 extend along the X direction and guide the table T. The second ball screw 430b includes a second screw shaft 431b and a second nut 432b.

[0127] The second screw shaft 431b extends along the X direction. A first end of the second screw shaft 431b is supported by the second support 423. The second support 423 includes a second bearing 440b that rotatably supports the second screw shaft 431b. The second bearing 440b is a ball bearing. Note that the second bearing 440b may also be a roller bearing.

[0128] A second end of the second screw shaft 431b is fixed to the output shaft of a second motor 450b so as to be rotatable together with the second screw shaft 431b. The second motor 450b rotates the second screw shaft 431b. The second motor 450b is equipped with a second rotary encoder 451b that detects the amount of rotation of the output shaft. The detection result of the second rotary encoder 451b is transmitted to the control device 4.

[0129] The second nut 432b is fitted onto the second screw shaft 431b so as to be rotatable relative to the second nut 432b. A plurality of balls are arranged inside the second nut 432b. As the second screw shaft 431b rotates, the plurality of balls circulate inside the second nut 432b. The table T is fixed to the second nut 432b. As the second screw shaft 431b rotates, the second nut 432b and the table T move along the X direction.

[0130] The first ball screw 430a and the second ball screw 430b have the same configuration. That is, the first screw shaft 431a and the second screw shaft 431b have the same configuration. Furthermore, the first nut 432a and the second nut 432b have the same configuration.

[0131] Furthermore, the first bearing 440a and the second bearing 440b are configured similarly to each other, the first motor 450a and the second motor 450b are configured similarly to each other, and the first rotary encoder 451a and the second rotary encoder 451b are configured similarly to each other.

[0132] Hereinafter, when the first ball screw 430a and the second ball screw 430b are described without distinction from one another, they will be simply referred to as "ball screw 430." Similarly, when the first screw shaft 431a and the second screw shaft 431b are described without distinction from one another, they will be simply referred to as "screw shaft 431," and when the first nut 432a and the second nut 432b are described without distinction from one another, they will be simply referred to as "nut 432." The screw shaft 431 corresponds to the "first member" in the second embodiment. The "nut 432" corresponds to the "second member" in the second embodiment.

[0133] Furthermore, when the first bearing 440a and the second bearing 440b are described without distinction, they are simply referred to as "bearings 440." When the first motor 450a and the second motor 450b are described without distinction, they are simply referred to as "motor 450." When the first rotary encoder 451a and the second rotary encoder 451b are described without distinction, they are simply referred to as "rotary encoder 451."

[0134] Fig. 11 is a side view of the ball screw 430 shown in Fig. 10. The ball screw 430 further includes a temperature detector 33. The temperature detector 33 detects the temperature of the screw shaft 431. The temperature detector 33 is disposed on an end face F3 of the screw shaft 431. The temperature detector 33 is the same as the temperature detector 33 of the first embodiment described above.

[0135] The temperature sensor 33b detects the temperature of the screw shaft 431. That is, the temperature detected by the temperature sensor 33b corresponds to the temperature detected by the temperature detection device 33. When the temperature detection device 33 is disposed on the screw shaft 431, the temperature sensor 33b faces the end face F3 of the screw shaft 431, similar to the first embodiment described above.

[0136] 10 performs wireless communication with the RFID tag 33a in the same manner as in the first embodiment. Therefore, the reader / writer 3 and the RFID tag 33a can communicate with each other even when the screw shaft 431 is rotating.

[0137] The control device 4 adjusts the position of the table T by controlling the amount of rotation of the screw shaft 431. Specifically, the control device 4 calculates the amount of movement of the table T in the X direction and the Y direction based on the difference between the target position and the current position of the table T. The amount of movement of the table T in the X direction corresponds to the amount of movement of the second nut 432b. The amount of movement of the table T in the Y direction corresponds to the amount of movement of the first nut 432a.

[0138] The amount of movement of the nut 432 is calculated based on the rotation angle (general angle) of the screw shaft 431 and the lead of the screw shaft 431. The rotation angle of the screw shaft 431 corresponds to the amount of rotation of the screw shaft 431. The amount of rotation of the screw shaft 431 corresponds to the amount of rotation of the motor 450. The control device 4 controls the amount of rotation of the screw shaft 431 by controlling the amount of rotation of the motor 450. The control device 4 controls the amount of rotation of the motor 450 based on the detection result of the rotary encoder 451.

[0139] The control device 4 derives the rotation amount of the motor 450 based on the movement amount of the table T, and drives the motor 450 with the rotation amount of the motor 450 that has been derived, thereby positioning the table T at the target position.

[0140] Furthermore, when the temperature of the screw shaft 431 changes, the length of the screw shaft 431 changes, and the lead of the screw shaft 431 also changes. The change in the lead of the screw shaft 431 affects the amount of movement of the nut 432 and the position of the table T. Therefore, the control device 4 corrects the amount of rotation of the screw shaft 431 based on the temperature detected by the temperature sensor 33b. The control device 4 corrects the amount of rotation of the screw shaft 431 by correcting the amount of rotation of the motor 450.

[0141] The reader / writer 3 performs wireless communication with the RFID tag 33 a provided in the mechanical device 402 , as in the first embodiment.

[0142] The control device 4 acquires the temperature detected by the temperature sensor 33b from the reader / writer 3, as in the first embodiment. The control device 4 derives a correction coefficient using the temperature detected by the temperature sensor 33b. The higher the temperature of the screw shaft 431, the longer the lead of the screw shaft 431. Therefore, the higher the temperature detected by the temperature sensor 33b, the larger the correction coefficient. The relationship between the temperature detected by the temperature sensor 33b and the correction coefficient is derived through experiments, simulations, etc., and is stored in advance in the internal storage unit of the control device 4.

[0143] The control device 4 multiplies the amount of rotation of the motor 450, which is derived based on the amount of movement of the table T as described above, by a correction coefficient. This corrects the amount of rotation of the screw shaft 431, and the positions of the nut 432 and the table T are adjusted with high precision.

[0144] The user can adjust the position of the table T with high precision by periodically checking the temperature detected by the temperature sensor 33b.

[0145] Furthermore, the control device 4 detects an abnormality in the bearings 440 of the first support 413 and the second support 423 before a failure occurs in the bearings 440, based on the temperature detected by the temperature sensor 33b.

[0146] An abnormality in the bearing 440 occurs when the temperature of the screw shaft 431 rises and the dimensional relationship between the screw shaft 431 and the bearing 440 changes. When the temperature of the screw shaft 431 rises, the diameter of the screw shaft 431 increases, causing an abnormality such as damage to the bearing 440. If the abnormality in the bearing 440 progresses, a failure such as seizure of the bearing 440 occurs.

[0147] Therefore, when the temperature detected by the temperature detector 33 is equal to or higher than a predetermined temperature, the control device 4 determines that there is an abnormality in the bearing 440. Therefore, by arranging the temperature detector 33 on the screw shaft 431, an abnormality in the bearing 440 can be detected early.

[0148] The control device 4 stores the temperature detected by the temperature sensor 33b in association with the above-mentioned identification information. Thus, the control device 4 can identify the bearing 440 determined to have an abnormality. Based on the determination result of the control device 4, the user investigates the bearing 440 determined to have an abnormality.

[0149] By periodically checking the temperature detected by the temperature sensor 33b using the control device 4, the user can detect an abnormality in the bearing 440, i.e., an abnormality in the mechanical device 402, at an early stage.

[0150] As described above, according to this embodiment, the mechanical device 402 includes the screw shaft 431, the nut 432 into which the screw shaft 431 is fitted so as to be relatively rotatable (relatively movable), and the RFID tag 33a which has a temperature sensor 33b that detects the temperature of the screw shaft 431 and transmits the temperature detected by the temperature sensor 33b to the reader / writer 3. The temperature sensor 33b is disposed on the end face F3 of the screw shaft 431.

[0151] This makes it possible to simplify the configuration of the mechanical device 402, as described above, even when the mechanical device 402 is equipped with a screw shaft 431 and a nut 432 that is fitted to the screw shaft 431 so as to be able to rotate relative to the screw shaft 431, and also contributes to earlier detection of abnormalities in the mechanical device 402 based on the temperature of the screw shaft 431.

[0152] Furthermore, when the temperature sensor 33b is disposed on the end face F3 of the screw shaft 431, the centrifugal force acting on the temperature sensor 33b can be reduced compared to when the temperature sensor 33b is disposed on the outer circumferential surface of the screw shaft 431. Therefore, failure of the temperature sensor 33b can be suppressed.

[0153] In the temperature control system 1b, the control device 4 controls the rotation amount of the screw shaft 431 and corrects the rotation amount of the screw shaft 431 based on the detection result of the temperature sensor 33b.

[0154] According to this, the control device 4 corrects the amount of rotation of the screw shaft 431 based on the temperature detected by the temperature sensor 33b, thereby correcting the amount of movement of the nut 432. Therefore, in the mechanical device 402, the influence of temperature changes on the screw shaft 431 can be suppressed.

[0155] Next, a temperature control system 1a and a mechanical device 402 according to a modified example of the second embodiment of the present disclosure will be described, mainly focusing on the differences from the temperature control system 1a and the mechanical device 402 of the second embodiment described above.

[0156] For example, the mechanical device 402 may be a device (eg, a robot arm) that includes a ball screw 430 rather than an XY table.

[0157] The temperature detecting device 33 may also be disposed on the circumferential side surface of the screw shaft 431. The temperature detecting device 33 may also be disposed on the nut 432. In this case, the temperature detecting device 33 detects the temperature of the screw shaft 431 via the nut 432.

[0158] Third Embodiment Next, a temperature management system 1b and a mechanical device 530 according to a third embodiment of the present disclosure will be described, mainly focusing on differences from the temperature management system 1 and the mechanical device 20 according to the first embodiment described above.

[0159] <Temperature Control System 1b> Fig. 12 is a diagram showing the configuration of a temperature control system 1b according to a third embodiment of the present disclosure. The temperature control system 1b is a system that monitors mechanical equipment 505 including a mechanical device 530, which will be described later. The temperature control system 1b includes the mechanical equipment 505, a reader / writer 3, and a control device 4. The reader / writer 3 and the control device 4 are the same as the reader / writer 3 and the control device 4 of the first embodiment described above. Note that the temperature control system 1b may include a plurality of pieces of mechanical equipment 505.

[0160] The machine equipment 505 is an XY table that moves the workpiece in the X and Y directions. The machine equipment 505 includes a fixed part 510, a moving part 520, and a table T on which the workpiece is placed.

[0161] The fixed unit 510 includes a first base 511, two first mechanical devices 530a, and a first ball screw 540a. The two first mechanical devices 530a and the first ball screw 540a are arranged on an upper surface 511a (the surface on the +Z side) of the first base 511.

[0162] The first mechanical device 530a is a linear guide that guides the moving part 520 along the Y direction. The first mechanical device 530a includes a first guide rail 531a extending along the Y direction, two first sliders 532a attached to the first guide rail 531a so as to be slidable relative to the first guide rail 531a, and a plurality of first rolling elements (not shown in FIG. 1 ) that roll between the first guide rail 531a and the first sliders 532a. The moving part 520 is fixed to the first sliders 532a. Details of the first mechanical device 530a will be described later.

[0163] The first ball screw 540a includes a first screw shaft 541a and a first nut 542a.

[0164] The first screw shaft 541a extends along the Y direction. A first end of the first screw shaft 541a is supported by a first support 512. The first support 512 includes a first bearing 550a that rotatably supports the first screw shaft 541a. The first bearing 550a is, for example, a rolling bearing.

[0165] A second end of the first screw shaft 541a is fixed to an output shaft of a first motor 560a so as to be rotatable together with the first screw shaft 541a. The first motor 560a rotates the first screw shaft 541a.

[0166] The first nut 542a is fitted onto the first screw shaft 541a so as to be rotatable relative to the first nut 542a. A plurality of balls are arranged inside the first nut 542a. As the first screw shaft 541a rotates, the plurality of balls circulate inside the first nut 542a. The moving part 520 is fixed to the first nut 542a. As the first screw shaft 541a rotates, the first nut 542a, the first slider 532a, and the moving part 520 move along the Y direction.

[0167] The moving unit 520 includes a second base 521, two second mechanical devices 530b, and a second ball screw 540b. A first slider 532a and a first nut 542a are fixed to the rear surface (-Z side surface) of the second base 521. The two second mechanical devices 530b and the second ball screw 540b are disposed on the upper surface 521a (+Z side surface) of the second base 521.

[0168] The second mechanical device 530b guides the table T along the X direction. The second mechanical device 530b includes a second guide rail 531b extending along the X direction, two second sliders 532b attached to the second guide rail 531b so as to be slidable relative to the second guide rail 531b, and a plurality of second rolling elements (not shown in FIG. 1 ) that roll between the second guide rail 531b and the second sliders 532b. The table T is fixed to the second sliders 532b. Details of the second mechanical device 530b will be described later.

[0169] The second ball screw 540b includes a second screw shaft 541b and a second nut 542b.

[0170] The second screw shaft 541b extends along the X direction. A first end of the second screw shaft 541b is supported by the second support 522. The second support 522 includes a second bearing 550b that rotatably supports the second screw shaft 541b. The second bearing 550b is a rolling bearing.

[0171] A second end of the second screw shaft 541b is fixed to an output shaft of a second motor 560b so as to be rotatable together with the second screw shaft 541b. The second motor 560b rotates the second screw shaft 541b.

[0172] The second nut 542b is fitted onto the second screw shaft 541b so as to be rotatable relative to the second nut 542b. A plurality of balls are arranged inside the second nut 542b. As the second screw shaft 541b rotates, the plurality of balls circulate inside the second nut 542b. The table T is fixed to the second nut 542b. As the second screw shaft 541b rotates, the second nut 542b, the second slider 532b, and the table T move along the X direction.

[0173] The first ball screw 540a and the second ball screw 540b have the same configuration. The first bearing 550a and the second bearing 550b have the same configuration. The first motor 560a and the second motor 560b have the same configuration.

[0174] The first mechanical device 530a and the second mechanical device 530b are configured similarly to each other, i.e., the first guide rail 531a and the second guide rail 531b, the first slider 532a and the second slider 532b, and the first rolling element and the second rolling element are configured similarly to each other.

[0175] Hereinafter, when the first mechanical device 530a and the second mechanical device 530b are described without distinction, they will be simply referred to as "mechanical device 530." Similarly, when the first guide rail 531a and the second guide rail 531b are described without distinction, they will be simply referred to as "guide rail 531." When the first slider 532a and the second slider 532b are described without distinction, they will be simply referred to as "slider 532." Furthermore, when the first rolling element and the second rolling element are described without distinction, they will be simply referred to as "rolling element B." The slider 532 corresponds to the "first member" in the third embodiment. The "guide rail 531" corresponds to the "second member" in the third embodiment.

[0176] The mechanical device 530 also includes a temperature sensor 33b that detects the temperature of the slider 532, as will be described later, and an RFID tag 33a that is integrated with the temperature sensor 33b.

[0177] The reader / writer 3 performs wireless communication with the RFID tag 33 a provided in the mechanical device 530 , as in the first embodiment.

[0178] The control device 4 acquires the temperature detected by the temperature sensor 33b from the reader / writer 3. The control device 4 detects an abnormality in the mechanical device 530 before a failure occurs in the mechanical device 530 based on the temperature detected by the temperature sensor 33b.

[0179] An abnormality in the mechanical device 530 occurs when the condition of the mechanical device 530 changes (for example, due to aging) due to the slider 532 repeatedly sliding against the guide rail 531. If the abnormality in the mechanical device 530 is overlooked, the mechanical device 530 will break down. In other words, the control device 4 detects an abnormality in the mechanical device 530 that occurs before the mechanical device 530 breaks down.

[0180] As the state change of the mechanical device 530 progresses, the temperature detected by the temperature sensor 33b rises (details will be described later). If the temperature detected by the temperature sensor 33b is equal to or higher than a predetermined temperature, the control device 4 determines that there is an abnormality in the mechanical device 530. Based on the determination result of the control device 4, the user investigates the mechanical device 530 that has been determined to have an abnormality.

[0181] By periodically checking the temperature detected by the temperature sensor 33b using the control device 4, the user can detect abnormalities in the mechanical device 530 at an early stage.

[0182] <Mechanical Device 530> Fig. 13 is a diagram showing the configuration of the mechanical device 530 shown in Fig. 12. Fig. 14 is a cross-sectional view of the mechanical device 530 taken along line XIV-XIV shown in Fig. 13.

[0183] The first direction D1 shown in the figure is the direction in which the guide rail 531 extends. The second direction D2 is perpendicular to the first direction D1 and parallel to the mounting surface H (the upper surface 511 a of the first base 511 or the upper surface 521 a of the second base 521) on which the guide rail 531 is disposed. The third direction D3 is perpendicular to the mounting surface H and perpendicular to the first direction D1 and the second direction D2.

[0184] As described above, the mechanical device 530 includes the guide rail 531, the slider 532, and a plurality of rolling elements B. The rolling elements B are spherical. However, the rolling elements B may also be columnar.

[0185] The guide rail 531 is linear. The outer surface of the guide rail 531 has a pair of first rail grooves Gr1 and a pair of second rail grooves Gr2. The first rail groove Gr1 and the second rail groove Gr2 extend in the same direction as the guide rail 531 extends.

[0186] The slider 532 is attached so as to be slidable relative to the guide rail 531. The sliding direction of the slider 532 is the direction in which the guide rail 531 extends (i.e., the first direction D1).

[0187] The slider 532 has a U-shaped cross section that is open toward the mounting surface H. The slider 532 has a pair of first slider grooves Gs1 facing the pair of first rail grooves Gr1 and a pair of second slider grooves Gs2 facing the pair of second rail grooves Gr2. The second base 521 or the table T is fixed to an opposite surface S2 of the slider 532, which is opposite to the opposing surface S1 that faces the mounting surface H, as described above.

[0188] When the slider 532 moves relative to the guide rail 531, the rolling element B rolls between the first rail groove Gr1 and the first slider groove Gs1 and between the second rail groove Gr2 and the second slider groove Gs2 in the direction opposite to the sliding direction.

[0189] The slider 532 further has a pair of first rolling paths Rt1 and a pair of second rolling paths Rt2. The first rolling paths Rt1 connect both ends of the first slider groove Gs1 and are paths along which the rolling elements B can roll. When the slider 532 moves relative to the guide rail 531, the first rail groove Gr1, the first slider groove Gs1, and the first rolling paths Rt1 form a first circulation path Rc1 along which the rolling elements B circulate.

[0190] The second rolling path Rt2 connects both ends of the second slider groove Gs2 and is a passage in which the rolling elements B can roll. When the slider 532 moves relative to the guide rail 531, the second rail groove Gr2, the second slider groove Gs2, and the second rolling path Rt2 form a second circulation path Rc2 in which the multiple rolling elements B circulate.

[0191] The first circulation path Rc1 and the second circulation path Rc2 are spaced apart in the third direction D3. Hereinafter, when the first circulation path Rc1 and the second circulation path Rc2 are described without distinction, they will be simply referred to as the "circulation path Rc." When multiple rolling elements B circulate through the circulation path Rc, frictional force is generated between the circulation path Rc and the rolling elements B.

[0192] The mechanical device 530 further includes a temperature detection device 33. The temperature detection device 33 detects the temperature of the slider 532. The temperature detection device 33 is disposed on an outer surface F4 of the slider 532.

[0193] Fig. 15 is a cross-sectional view of the temperature detection device 33 shown in Fig. 14. Fig. 15 shows a state in which the temperature detection device 33 is disposed on the slider 532. The temperature detection device 33 is the same as the temperature detection device 33 in the first embodiment. The temperature sensor 33b detects the temperature of the slider 532. In other words, the detected temperature of the temperature sensor 33b corresponds to the detected temperature of the temperature detection device 33.

[0194] The temperature sensor 33b is disposed on the main surface 33a2 of the substrate 33a1. When the temperature detection device 33 is disposed on the slider 532, the temperature sensor 33b faces the outer surface F4 of the slider 532. There is a space between the temperature sensor 33b and the outer surface F4 of the slider 532. This prevents vibrations from the slider 532 from being transmitted to the temperature sensor 33b, thereby preventing failure of the temperature sensor 33b.

[0195] Furthermore, the temperature sensor 33b overlaps with the circulation path Rc when the slider 532 is viewed in a direction perpendicular to the sliding direction of the slider 532. In the third embodiment, the temperature sensor 33b overlaps with the circulation path Rc when the slider 532 is viewed in the second direction D2.

[0196] 14 shows a state in which the temperature sensor 33b overlaps with the first circulation path Rc1 when the slider 532 is viewed in the second direction D2. The temperature sensor 33b may overlap with the second circulation path Rc2 when the slider 532 is viewed in the second direction D2. Note that the temperature sensor 33b may be disposed in a state in which it overlaps with the circulation path Rc when the slider 532 is viewed in the first direction D1.

[0197] Next, the operation of the mechanical device 530 when an abnormality occurs in the mechanical device 530 will be described.

[0198] As described above, when the rolling element B circulates through the circulation path Rc, a frictional force is generated between the circulation path Rc and the rolling element B. If the state of the mechanical device 530 continues to change due to this frictional force, abnormalities such as damage to the rolling element B, the guide rail 531, and the slider 532 may occur. If this abnormality progresses, there is a possibility that a failure such as seizure may occur.

[0199] Furthermore, as the state change of the mechanical device 530 due to frictional force progresses, the temperatures of the rolling element B, the guide rail 531, and the slider 532 rise. When the slider 532 slides, the rolling element B constantly rolls in the first slider groove Gs1, the second slider groove Gs2, the first rolling path Rt1, and the second rolling path Rt2 that form the circulation path Rc in the slider 532. Therefore, the temperatures of the rolling element B and the slider 532 rise earlier than the temperature of the guide rail 531.

[0200] Furthermore, the portion of the slider 532 near the circulation path Rc is closer to the rolling element B than other portions of the slider 532. Therefore, the temperature of the portion of the slider 532 near the circulation path Rc rises earlier than the temperature of other portions of the slider 532.

[0201] 13, in the slider 532, the rolling element B rolls over a longer distance in the regions on both sides in the second direction D2 than in the regions on both sides in the first direction D1. Therefore, the temperature of the regions on both sides in the second direction D2 rises earlier than the temperature of the regions on both sides in the first direction D1.

[0202] As described above, the temperature sensor 33b is located at a position overlapping the circulation path Rc when the slider 532 is viewed in the second direction D2. In other words, when the slider 532 is viewed in the second direction D2, the temperature sensor 33b overlaps with a portion of the slider 532 where the temperature rises early. Therefore, the temperature detected by the temperature sensor 33b rises earlier than when the temperature sensor 33b is located in another position.

[0203] As described above, the temperature detected by the temperature detector 33 is stored in the control device 4 via the reader / writer 3. Furthermore, if the temperature detected by the temperature detector 33 is equal to or higher than a predetermined temperature, the control device 4 determines that there is an abnormality in the mechanical device 530. Therefore, the temperature management system 1b can detect an abnormality in the mechanical device 530 at an early stage.

[0204] As described above, according to this embodiment, the mechanical device 530 includes a guide rail 531, a slider 532 attached to the guide rail 531 so as to be slidable relative to the guide rail 531, and an RFID tag 33a having a temperature sensor 33b that detects the temperature of the slider 532 and transmitting the temperature detected by the temperature sensor 33b to the reader / writer 3. The mechanical device 530 further includes a rolling element B that rolls between the guide rail 531 and the slider 532. The slider 532 has a circulation path Rc along which the rolling element B circulates. When the slider 532 is viewed in a direction perpendicular to the sliding direction of the slider 532, the temperature sensor 33b overlaps with the circulation path Rc.

[0205] This makes it possible to simplify the configuration of the mechanical device 530 as described above, even when the mechanical device 530 is equipped with a guide rail 531 and a slider 532 that is slidably attached (capable of relative movement) to the guide rail 531, and also contributes to earlier detection of abnormalities in the mechanical device 530 based on the temperature of the slider 532.

[0206] Furthermore, the temperature of the portion of the slider 532 that comes into contact with the rolling element B rises earlier than the temperature of other portions. Therefore, the portion of the outer surface of the slider 532 where the temperature sensor 33b is located rises earlier in response to the temperature rise of the slider 532. Therefore, the mechanical device 530 can reliably contribute to early detection of an abnormality by the temperature detected by the temperature sensor 33b.

[0207] Next, a temperature control system 1b and a mechanical device 530 according to a modified embodiment of the present disclosure will be described, focusing mainly on the differences from the temperature control system 1b and the mechanical device 530 according to the third embodiment described above.

[0208] For example, the mechanical equipment 505 may be equipment including a mechanical device 530 (for example, a machine tool) instead of an XY table.

[0209] Furthermore, it goes without saying that the number of sliders 532 attached to one guide rail 531 is not limited to two, but may be one or three or more.

[0210] Furthermore, when a member such as a table T is not fixed to the opposite surface S2 of the slider 532, the temperature detection device 33 may be disposed on the opposite surface S2. In this case, the temperature sensor 33b may be disposed so as to overlap with the circulation path Rc when the slider 532 is viewed along the third direction D3. Furthermore, when the slider 532 is viewed along a direction perpendicular to the sliding direction of the slider 532, the temperature sensor 33b may be disposed so as not to overlap with the circulation path Rc.

[0211] Fourth Embodiment Next, a temperature control system 1c and a mechanical device 610 according to a fourth embodiment of the present disclosure will be described, focusing mainly on the differences from the temperature control system 1 of the first embodiment described above.

[0212] <Temperature Control System 1c and Mechanical Device 610> Figure 16 is a diagram showing the configuration of a temperature control system 1c according to a fourth embodiment of the present disclosure. The temperature control system 1c includes a mechanical device 610, a first temperature detection device 620, a second temperature detection device 630, a reader / writer 3, and a control device 4. The reader / writer 3 and the control device 4 are the same as the reader / writer 3 and the control device 4 of the first embodiment described above.

[0213] The mechanical device 610 is a ball screw used to move the object T0. The object T0 is, for example, a mold of an injection molding machine, a spindle head of a machine tool, or a table of an XY table. The mechanical device 610 includes a screw shaft 611 (corresponding to the "first member" in the fourth embodiment), a nut 612 (corresponding to the "second member" in the fourth embodiment), and a plurality of balls 613.

[0214] The screw shaft 611 has a cylindrical shape extending along a central axis CL. The screw shaft 611 has a first spiral groove 611a on its outer circumferential surface. The screw shaft 611 is connected to, for example, the output shaft of a motor and rotates when driven by the motor.

[0215] The nut 612 is fitted onto the screw shaft 611 so as to be rotatable relative to the screw shaft 611. The nut 612 uses a tube system for circulating the balls 613. The nut 612 includes a main body 612a, an attachment member 612b, and a plurality of circulation members 612c.

[0216] The main body 612a is cylindrical and has a through hole 612a1 through which the screw shaft 611 passes. The inner circumferential surface of the through hole 612a1 has a spiral second groove 612a2 that faces the first groove 611a of the screw shaft 611. The first groove 611a and the second groove 612a2 form a passage R for the plurality of balls 613.

[0217] The mounting member 612b is disposed on one end surface of the main body 612a. The screw shaft 611 passes through the mounting member 612b. The object T0 is attached to the mounting member 612b. Note that the mounting member 612b may also be disposed on a side surface of the main body 612a.

[0218] Fig. 17 is a side view of the mechanical device 610 as seen along the arrow XVII shown in Fig. 16. The arrow XVII shown in Fig. 16 extends along the radial direction of the screw shaft 611.

[0219] 16 and 17 , the circulation member 612c is tubular. The inside of the circulation member 612c forms a passage R for the balls 613. Both ends of the circulation member 612c open to different positions of the second groove 612a2 in the direction of the central axis CL. When the screw shaft 611 and the nut 612 rotate relative to each other, the multiple balls 613 circulate between the first groove 611a and the second groove 612a2 that form the passage R and inside the circulation member 612c. Note that grease is applied to the passage R to facilitate the circulation of the balls 613.

[0220] The nut 612 has a plurality of circulation members 612c. The number of circulation members 612c is five, but it goes without saying that the number is not limited to five.

[0221] The circulation member 612c has a protrusion 612c1 that protrudes from the main body 612a. The protrusion 612c1 of the circulation member 612c is inclined with respect to the central axis CL of the screw shaft 611 when the mechanical device 610 is viewed along the radial direction of the screw shaft 611. The protrusions 612c1 of the multiple circulation members 612c are aligned along the central axis CL of the screw shaft 611.

[0222] Fig. 18 is a cross-sectional view of the first temperature detecting device 620 shown in Fig. 16. Fig. 18 shows a state in which the first temperature detecting device 620 is disposed on the screw shaft 611.

[0223] The first temperature detecting device 620 has a configuration similar to that of the temperature detecting device 33 of the first embodiment. The first temperature detecting device 620 includes a first RFID tag 621 (corresponding to the "RFID tag" in the fourth embodiment) including a substrate 621a, a first temperature sensor 622 (corresponding to the "temperature sensor" in the fourth embodiment), a first cover member 623, and a first adhesive member 624. The substrate 621a, the first RFID tag 621, the first temperature sensor 622, the first cover member 623, and the first adhesive member 624 are configured similarly to the substrate 33a1, the RFID tag 33a, the temperature sensor 33b, the cover member 33c, and the adhesive member 33d in the temperature detecting device 33 of the first embodiment. The first RFID tag 621 is configured integrally with the first temperature sensor 622.

[0224] 16 and 18 , the first temperature detecting device 620 is disposed on the end face F5 of the screw shaft 611. That is, the first RFID tag 621 is disposed on the end face F5 of the screw shaft 611. The first RFID tag 621 performs wireless communication with the reader / writer 3. The first temperature sensor 622 detects the temperature of the screw shaft 611.

[0225] Similarly to the RFID tag 33a of the first embodiment, the first RFID tag 621 transmits to the reader / writer 3 identification information (e.g., an identification number) that identifies the mechanical device 610 and identification information that identifies the first RFID tag 621 in association with the temperature detected by the first temperature sensor 622. The identification information is stored in advance in the first RFID tag 621 by the reader / writer 3.

[0226] With the first temperature detection device 620 affixed to the end face F5 of the screw shaft 611, the first temperature sensor 622 faces the end face F5 of the screw shaft 611. There is a space between the first temperature sensor 622 and the end face F5 of the screw shaft 611. This prevents vibrations from the screw shaft 611 from being transmitted to the first temperature sensor 622, thereby preventing failure of the first temperature sensor 622.

[0227] The second temperature detecting device 630 is configured similarly to the first temperature detecting device 620. The second temperature detecting device 630 includes a second RFID tag 631 (corresponding to a "second RFID tag": including a substrate 631a) corresponding to the first RFID tag 621, a second temperature sensor 632 (corresponding to a "second temperature sensor") corresponding to the first temperature sensor 622, a second cover member 633 corresponding to the first cover member 623, and a second adhesive member 634 corresponding to the first adhesive member 624. The substrate 631a corresponds to the substrate 621a.

[0228] As shown in Figures 16, 17, and 18, the second temperature detection device 630 is disposed on the outer surface F6 of the main body 612a of the nut 612. A second adhesive member 634 adheres the second RFID tag 631 and the second cover member 633 to the outer surface F6 of the main body 612a of the nut 612. The second temperature sensor 632 faces the outer surface F6 of the main body 612a. The second temperature sensor 632 detects the temperature of the nut 612. There is a space between the second temperature sensor 632 and the outer surface F6 of the main body 612a. This prevents vibrations from the nut 612 from being transmitted to the second temperature sensor 632, thereby preventing malfunction of the second temperature sensor 632.

[0229] The temperature management system 1c also includes a plurality of second temperature detecting devices 630. The number of second temperature detecting devices 630 is four, but it goes without saying that the number is not limited to four. As shown in FIG. 17 , the plurality of second temperature detecting devices 630 are aligned in a line along the central axis CL. Furthermore, each of the plurality of second temperature detecting devices 630 is disposed in a region between two adjacent protrusions 612c1 of the plurality of protrusions 612c1 on the main body 612a. That is, the plurality of second RFID tags 631 are aligned in a line along the central axis CL. Furthermore, each of the plurality of second RFID tags 631 is disposed in a region between two adjacent protrusions 612c1 on the main body 612a. It goes without saying that the positions of the second temperature detecting devices 630 are not limited to the positions shown in FIGS. 16 and 17 .

[0230] Furthermore, when viewed along the radial direction of the screw shaft 611, the second temperature sensors 632 of the multiple second temperature detecting devices 630 overlap with the passages R of the balls 613 of the nut 612. Specifically, when viewed along the radial direction of the screw shaft 611, the second temperature sensors 632 overlap with the second grooves 612a2.

[0231] 16, similar to the first embodiment, performs wireless communication with the first RFID tag 621 and the second RFID tag 631. The reader / writer 3 and the first RFID tag 621 and the second RFID tag 631 can communicate with each other even when the screw shaft 611 is rotating.

[0232] Similarly to the first RFID tag 621, the second RFID tag 631 transmits to the reader / writer 3 identification information (e.g., an identification number) that identifies the mechanical device 610 and identification information that identifies the second RFID tag 631 in association with the temperature detected by the second temperature sensor 632. The identification information is stored in advance in the second RFID tag 631 by the reader / writer 3.

[0233] A user operates the reader / writer 3, which transmits a carrier wave to the first RFID tag 621 and the second RFID tag 631. In response, the first RFID tag 621 transmits each piece of identification information and the temperature detected by the first temperature sensor 622 to the reader / writer 3. The second RFID tag 631 also transmits each piece of identification information and the temperature detected by the second temperature sensor 632 to the reader / writer 3.

[0234] The reader / writer 3 acquires each piece of identification information, the temperature detected by the first temperature sensor 622 , and the temperature detected by the second temperature sensor 632 , and transmits them to the control device 4 .

[0235] The control device 4 controls the rotation amount of the motor, thereby controlling the rotation amount of the screw shaft 611 and the movement amount of the nut 612. When the nut 612 rotates relative to the screw shaft 611, the balls 613 circulate between the screw shaft 611 and the nut 612, and the temperatures of the screw shaft 611 and the nut 612 rise due to friction between the screw shaft 611 and the balls 613 and friction between the nut 612 and the balls 613. In addition, the nut 612 moves back and forth relative to the screw shaft 611. As a result, the temperature of the screw shaft 611 becomes approximately the same over the entire screw shaft 611.

[0236] The control device 4 acquires each piece of identification information, the detected temperature of the first temperature sensor 622, and the detected temperatures of the plurality of second temperature sensors 632 from the reader / writer 3. The control device 4 associates the detected temperatures of the first temperature sensor 622 and the second temperature sensor 632 with each piece of identification information and stores them in chronological order in an internal storage unit. The control device 4 also displays the detected temperatures of the first temperature sensor 622 and the second temperature sensor 632 on a display unit (e.g., a display) in association with each piece of identification information.

[0237] Furthermore, the control device 4 calculates the temperature difference between each of the temperatures detected by the plurality of second temperature sensors 632 and the temperature detected by the first temperature sensor 622. For example, when the amount of grease in the passage R becomes relatively small, the friction between the nut 612 and the ball 613 increases, and the temperature of the nut 612 becomes higher than the temperature of the screw shaft 611.

[0238] When the difference in temperature between the screw shaft 611 and the nut 612 increases, the difference in the amount of thermal expansion between the screw shaft 611 and the nut 612 also increases, narrowing the passage R of the balls 613 between the screw shaft 611 and the nut 612. This increases the friction between the screw shaft 611 and the balls 613 and between the nut 612 and the balls 613, potentially damaging the mechanical device 610. Damage to the mechanical device 610 affects the lifespan of the mechanical device 610.

[0239] Therefore, when the temperature difference between the temperature detected by the second temperature sensor 632 and the temperature detected by the first temperature sensor 622 is equal to or greater than a predetermined temperature difference, the control device 4 detects an abnormality in the mechanical device 610. When the temperature difference between the temperature detected by at least one second temperature sensor 632 among the temperatures detected by the multiple second temperature sensors 632 and the temperature detected by the first temperature sensor 622 is equal to or greater than a predetermined temperature difference, the control device 4 detects an abnormality in the mechanical device 610. The predetermined temperature difference is set to, for example, a temperature difference that will not damage the mechanical device 610, and is stored in advance in the internal memory of the control device 4.

[0240] When the control device 4 detects an abnormality in the mechanical device 610, it displays on a display unit (e.g., a display) that an abnormality in the mechanical device 610 has been detected. At this time, the control device 4 displays on the display unit the identification information of the second temperature sensor 632, among the temperatures detected by the multiple second temperature sensors 632, whose temperature difference from the temperature detected by the first temperature sensor 622 is equal to or greater than a predetermined temperature difference. Based on this display, the user performs maintenance on the mechanical device 610. For example, if the abnormality in the mechanical device 610 is due to a lack of grease, the user applies grease. By periodically checking the temperatures detected by the first temperature sensor 622 and the second temperature sensor 632 using the reader / writer 3, the user can detect an abnormality in the mechanical device 610 at an early stage.

[0241] In addition, if the object T0 attached to the nut 612 has a heat source, the control device 4 will detect an abnormality in the mechanical device 610 even if the temperature difference between the detected temperature of the second temperature sensor 632 and the detected temperature of the first temperature sensor 622 is greater than or equal to a predetermined temperature difference due to the heat from the heat source being transferred to the nut 612.

[0242] As described above, according to this embodiment, the mechanical device 610 includes the screw shaft 611, the nut 612 fitted onto the screw shaft 611 so as to be rotatable (movable) relative to the screw shaft 611, and the first RFID tag 621 having a first temperature sensor 622 that detects the temperature of the screw shaft 611 and transmitting the temperature detected by the first temperature sensor 622 to the reader / writer 3. The mechanical device 610 also includes a second RFID tag 631 having a second temperature sensor 632 that detects the temperature of the nut 612 and transmitting the temperature detected by the second temperature sensor 632 to the reader / writer 3.

[0243] According to this, even when the mechanical device 610 is equipped with a screw shaft 611 and a nut 612 that is fitted to the screw shaft 611 so as to be able to rotate relative to the screw shaft 611, as described above, the configuration of the mechanical device 610 can be simplified and abnormalities in the mechanical device 610 can be detected more quickly based on the temperature of the screw shaft 611 and the temperature of the nut 612.

[0244] Furthermore, the control device 4 detects an abnormality in the mechanical device 610 when the temperature difference between the temperature detected by the first temperature sensor 622 and the temperature detected by the second temperature sensor 632 is equal to or greater than a predetermined temperature difference.

[0245] According to this, the control device 4 wirelessly acquires the temperature of the screw shaft 611 and the temperature of the nut 612 via the first RFID tag 621, the second RFID tag 631, and the reader / writer 3. Therefore, the control device 4 can easily acquire the temperature of the screw shaft 611 and the temperature of the nut 612 even when the screw shaft 611 is rotating. Therefore, the control device 4 can easily manage the temperature of the screw shaft 611 and the temperature of the nut 612.

[0246] Furthermore, for example, if the temperature of the nut 612 rises due to friction between the nut 612 and the ball 613, the temperature difference between the temperature of the nut 612 and the temperature of the screw shaft 611 becomes relatively large. As a result, if the difference between the amount of thermal expansion of the nut 612 and the amount of thermal expansion of the screw shaft 611 becomes large, the friction between the screw shaft 611 and the ball 613 and the friction between the nut 612 and the ball 613 becomes relatively large, which may shorten the life of the mechanical device 610. Therefore, the control device 4 detects an abnormality in the mechanical device 610 when the temperature difference between the temperature of the screw shaft 611 and the temperature of the nut 612 is equal to or greater than a predetermined temperature difference. Therefore, the temperature management system 1c can prevent the life of the mechanical device 610 from being shortened.

[0247] The first RFID tag 621 is disposed on the end face F5 of the screw shaft 611.

[0248] This reduces the centrifugal force acting on the first RFID tag 621 compared to when the first RFID tag 621 is disposed on the outer circumferential surface of the screw shaft 611. Therefore, failure of the first RFID tag 621 can be suppressed.

[0249] The nut 612 also includes a main body 612a having a through hole 612a1 through which the screw shaft 611 passes, and a plurality of circulation members 612c that form passages for the balls 613. Each of the plurality of circulation members 612c has a protrusion 612c1 that protrudes from the main body 612a. The second RFID tag 631 is disposed in a position on the main body 612a between two of the plurality of protrusions 612c1.

[0250] When the friction between the circulation member 612c and the ball 613 becomes relatively large, the temperature of the circulation member 612c rises relatively quickly. Therefore, the second temperature sensor 632 of the second RFID tag 631 detects the temperature rise of the circulation member 612c early. As a result, the temperature difference between the detection results of the first temperature sensor 622 and the second temperature sensor 632 becomes large early. Therefore, the temperature management system 1c can detect an abnormality in the mechanical device 610 early.

[0251] Furthermore, the second temperature sensor 632 overlaps with the passage R of the ball 613 of the nut 612 when viewed along the radial direction of the screw shaft 611 .

[0252] According to this, when the temperature of the nut 612 rises due to friction between the ball 613 and the nut 612, the temperature of the nut 612 rises relatively quickly near the passage R of the ball 613. Therefore, the second temperature sensor 632 detects the temperature rise of the nut 612 near the passage R of the ball 613 early. As a result, the temperature difference between the temperature detected by the first temperature sensor 622 and the temperature detected by the second temperature sensor 632 becomes large early. Therefore, the temperature management system 1c can detect an abnormality in the mechanical device 610 early.

[0253] The temperature control system 1c also includes a plurality of second RFID tags 631. The plurality of second RFID tags 631 are arranged in a line along the central axis CL of the screw shaft 611.

[0254] This allows the user to easily obtain the temperatures detected by the multiple second temperature sensors 632 by moving the reader / writer 3 along the central axis CL of the screw shaft 611. This makes it possible to easily manage the temperature of the nut 612.

[0255] The temperature management system 1c also includes a plurality of second RFID tags 631. The control device 4 detects an abnormality in the mechanical device 610 when the temperature difference between the detection result of the second temperature sensor 632 of at least one of the plurality of second RFID tags 631 and the detection result of the first temperature sensor 622 is equal to or greater than a predetermined temperature difference.

[0256] This allows early detection of an abnormality in the mechanical device 610 even if there is an abnormality in part of the mechanical device 610.

[0257] Next, a temperature control system 1c and a mechanical device 610 according to a modified example of the fourth embodiment of the present disclosure will be described, focusing mainly on the differences from the temperature control system 1c of the fourth embodiment described above.

[0258] For example, the control device 4 may detect an abnormality in the mechanical device 610 when the temperature difference between the average value of the temperatures detected by the multiple second temperature sensors 632 and the temperature detected by the first temperature sensor 622 is equal to or greater than a predetermined temperature difference.

[0259] The first temperature detecting device 620 may also be disposed on the circumferential side surface of the screw shaft 611 .

[0260] The number of second temperature detecting devices 630 may be one.

[0261] Fig. 19 is a partial cross-sectional view taken along the central axis CL of a mechanical device 610 included in a temperature control system 1c according to a modified example of the fourth embodiment of the present disclosure. Fig. 20 is a cross-sectional view of the mechanical device 610 taken along line XX-XX shown in Fig. 19.

[0262] In this modified example, the nut 612 does not have a circulation member 612c. The circulation system of the balls 613 in the nut 612 of this modified example is a ball type. Figures 19 and 20 show a first link portion 712d1, a second link portion 712d2, a third link portion 712d3, and a fourth link portion 712d4. When the first link portion 712d1, the second link portion 712d2, the third link portion 712d3, and the fourth link portion 712d4 are described without distinction, they will be simply referred to as "link portions 712d."

[0263] The first link portion 712d1, the second link portion 712d2, the third link portion 712d3, and the fourth link portion 712d4 are arranged in this order along the central axis CL and are positioned at equal intervals around the central axis CL.

[0264] The link portion 712d faces the screw shaft 611 and has a link groove D that allows the balls 613 to ride up the threads of the screw shaft 611. The link grooves D of the first link portion 712d1, the second link portion 712d2, the third link portion 712d3, and the fourth link portion 712d4 are each positioned at equal intervals in the circumferential direction of the screw shaft 611.

[0265] The ball 613 passing between the first groove 611a and the second groove 612a2 moves via the groove D to the adjacent first groove 611a in the direction along the central axis CL, thereby circulating the ball 613 within the nut 612.

[0266] In this modification, the second temperature detecting device 630 may be arranged at a position where the second temperature sensor 632 overlaps with the groove D when viewed along the radial direction of the screw shaft 611. In this case, when a plurality of second temperature detecting devices 630 are arranged on the nut 612, the plurality of second temperature detecting devices 630 may be arranged at different positions in the circumferential direction of the nut 612 when viewed along the central axis CL.

[0267] The circulation system of the balls 613 in the nut 612 may be an end deflector system or an end cap system.

[0268] DESCRIPTION OF SYMBOLS 1 Temperature control system 3 Reader / writer 4 Control device 20 Mechanical device 31 Shaft member (first member) 33a RFID tag 33b Temperature sensor 42 Bearing (second member) 402 Mechanical device 431 Screw shaft (first member) 432 Nut (second member) 530 Mechanical device 531 Guide rail (second member) 532 Slider (first member) 610 Mechanical device 611 Screw shaft (first member) 612 Nut (second member) 612a Main body 612a1 Through hole 612b Mounting member 612c Circulation member 612c1 Protrusion 613 Ball 621 First RFID tag (RFID tag) 622 First temperature sensor (temperature sensor) 631 Second RFID tag (second RFID tag) 632 Second temperature sensor (second temperature sensor) B Rolling element CL Central axis F1, F3, F5 End face R Passage Rc Circulation path

Claims

1. A mechanical device comprising: a first member; a second member to which the first member is attached so as to be able to move relative to a second member; and an RFID tag having a temperature sensor that detects the temperature of the first member and transmits the temperature detected by the temperature sensor to a reader / writer.

2. The mechanical device according to claim 1, wherein the first member is a shaft member, the second member is a bearing that rotatably supports the first member, and the temperature sensor is disposed on an end face of the first member.

3. The mechanical device according to claim 1, wherein the first member is a screw shaft, the second member is a nut fitted to the first member so as to be capable of relative rotation, and the temperature sensor is disposed on an end face of the first member.

4. The mechanical device described in claim 1, further comprising a plurality of rolling elements that roll between the first member and the second member, the second member being a guide rail, the first member being a slider attached to the second member so as to be slidable relative to the second member, having a circulation path through which the rolling elements circulate, and when the first member is viewed along a direction perpendicular to the sliding direction of the first member, the temperature sensor overlaps with the circulation path.

5. The mechanical device according to claim 1, wherein the first member is a screw shaft, the second member is a nut fitted to the first member so as to be rotatable relative to the first member, and further comprising a second RFID tag having a second temperature sensor for detecting the temperature of the second member and transmitting the temperature detected by the second temperature sensor to a reader / writer.

6. A temperature management system comprising: the mechanical device according to claim 1; the reader / writer; and a control device electrically connected to the reader / writer and configured to store the temperature detected by the temperature sensor.

7. The temperature control system according to claim 6, comprising a plurality of said mechanical devices.

8. The temperature management system according to claim 6, wherein the first member is a screw shaft, the second member is a nut fitted to the first member so as to be rotatable relative to the first member, and the control device controls the amount of rotation of the first member and corrects the amount of rotation of the first member based on the detection result of the temperature sensor.

9. The temperature management system of claim 6, wherein the first member is a screw shaft, the second member is a nut fitted to the first member so as to be rotatable relative to the first member, the mechanical device further comprises: a plurality of balls circulating within the second member; and a second RFID tag having a second temperature sensor for detecting the temperature of the second member and transmitting the detected temperature of the second temperature sensor to the reader / writer, and the control device detects an abnormality in the mechanical device when the temperature difference between the detected temperature of the temperature sensor and the second temperature sensor is equal to or greater than a predetermined temperature difference.

10. The temperature control system according to claim 9, wherein the RFID tag is disposed on an end surface of the first member.

11. A temperature management system as described in claim 9, wherein the second member comprises a main body portion having a through hole through which the first member passes, and a plurality of circulation members forming a passage for the ball, each of the plurality of circulation members having a protrusion protruding from the main body portion, and the second RFID tag is positioned in a portion of the main body portion between two of the plurality of protrusions.

12. The temperature management system according to claim 9, wherein the second temperature sensor overlaps with the ball passage of the second member when viewed along the radial direction of the first member.

13. The temperature control system according to claim 9, comprising a plurality of said second RFID tags, said plurality of said second RFID tags being arranged in a line along the central axis of said first member.

14. The temperature management system of claim 9, further comprising a plurality of the second RFID tags, and wherein the control device detects an abnormality in the mechanical device when the temperature difference between the detection result of the second temperature sensor of at least one of the plurality of second RFID tags and the detection result of the temperature sensor is equal to or greater than a predetermined temperature difference.

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